diff options
Diffstat (limited to 'ANDROID_3.4.5/drivers/md/raid5.c')
| -rw-r--r-- | ANDROID_3.4.5/drivers/md/raid5.c | 6050 |
1 files changed, 0 insertions, 6050 deletions
diff --git a/ANDROID_3.4.5/drivers/md/raid5.c b/ANDROID_3.4.5/drivers/md/raid5.c deleted file mode 100644 index 73a58007..00000000 --- a/ANDROID_3.4.5/drivers/md/raid5.c +++ /dev/null @@ -1,6050 +0,0 @@ -/* - * raid5.c : Multiple Devices driver for Linux - * Copyright (C) 1996, 1997 Ingo Molnar, Miguel de Icaza, Gadi Oxman - * Copyright (C) 1999, 2000 Ingo Molnar - * Copyright (C) 2002, 2003 H. Peter Anvin - * - * RAID-4/5/6 management functions. - * Thanks to Penguin Computing for making the RAID-6 development possible - * by donating a test server! - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2, or (at your option) - * any later version. - * - * You should have received a copy of the GNU General Public License - * (for example /usr/src/linux/COPYING); if not, write to the Free - * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - */ - -/* - * BITMAP UNPLUGGING: - * - * The sequencing for updating the bitmap reliably is a little - * subtle (and I got it wrong the first time) so it deserves some - * explanation. - * - * We group bitmap updates into batches. Each batch has a number. - * We may write out several batches at once, but that isn't very important. - * conf->seq_write is the number of the last batch successfully written. - * conf->seq_flush is the number of the last batch that was closed to - * new additions. - * When we discover that we will need to write to any block in a stripe - * (in add_stripe_bio) we update the in-memory bitmap and record in sh->bm_seq - * the number of the batch it will be in. This is seq_flush+1. - * When we are ready to do a write, if that batch hasn't been written yet, - * we plug the array and queue the stripe for later. - * When an unplug happens, we increment bm_flush, thus closing the current - * batch. - * When we notice that bm_flush > bm_write, we write out all pending updates - * to the bitmap, and advance bm_write to where bm_flush was. - * This may occasionally write a bit out twice, but is sure never to - * miss any bits. - */ - -#include <linux/blkdev.h> -#include <linux/kthread.h> -#include <linux/raid/pq.h> -#include <linux/async_tx.h> -#include <linux/module.h> -#include <linux/async.h> -#include <linux/seq_file.h> -#include <linux/cpu.h> -#include <linux/slab.h> -#include <linux/ratelimit.h> -#include "md.h" -#include "raid5.h" -#include "raid0.h" -#include "bitmap.h" - -/* - * Stripe cache - */ - -#define NR_STRIPES 256 -#define STRIPE_SIZE PAGE_SIZE -#define STRIPE_SHIFT (PAGE_SHIFT - 9) -#define STRIPE_SECTORS (STRIPE_SIZE>>9) -#define IO_THRESHOLD 1 -#define BYPASS_THRESHOLD 1 -#define NR_HASH (PAGE_SIZE / sizeof(struct hlist_head)) -#define HASH_MASK (NR_HASH - 1) - -static inline struct hlist_head *stripe_hash(struct r5conf *conf, sector_t sect) -{ - int hash = (sect >> STRIPE_SHIFT) & HASH_MASK; - return &conf->stripe_hashtbl[hash]; -} - -/* bio's attached to a stripe+device for I/O are linked together in bi_sector - * order without overlap. There may be several bio's per stripe+device, and - * a bio could span several devices. - * When walking this list for a particular stripe+device, we must never proceed - * beyond a bio that extends past this device, as the next bio might no longer - * be valid. - * This function is used to determine the 'next' bio in the list, given the sector - * of the current stripe+device - */ -static inline struct bio *r5_next_bio(struct bio *bio, sector_t sector) -{ - int sectors = bio->bi_size >> 9; - if (bio->bi_sector + sectors < sector + STRIPE_SECTORS) - return bio->bi_next; - else - return NULL; -} - -/* - * We maintain a biased count of active stripes in the bottom 16 bits of - * bi_phys_segments, and a count of processed stripes in the upper 16 bits - */ -static inline int raid5_bi_phys_segments(struct bio *bio) -{ - return bio->bi_phys_segments & 0xffff; -} - -static inline int raid5_bi_hw_segments(struct bio *bio) -{ - return (bio->bi_phys_segments >> 16) & 0xffff; -} - -static inline int raid5_dec_bi_phys_segments(struct bio *bio) -{ - --bio->bi_phys_segments; - return raid5_bi_phys_segments(bio); -} - -static inline int raid5_dec_bi_hw_segments(struct bio *bio) -{ - unsigned short val = raid5_bi_hw_segments(bio); - - --val; - bio->bi_phys_segments = (val << 16) | raid5_bi_phys_segments(bio); - return val; -} - -static inline void raid5_set_bi_hw_segments(struct bio *bio, unsigned int cnt) -{ - bio->bi_phys_segments = raid5_bi_phys_segments(bio) | (cnt << 16); -} - -/* Find first data disk in a raid6 stripe */ -static inline int raid6_d0(struct stripe_head *sh) -{ - if (sh->ddf_layout) - /* ddf always start from first device */ - return 0; - /* md starts just after Q block */ - if (sh->qd_idx == sh->disks - 1) - return 0; - else - return sh->qd_idx + 1; -} -static inline int raid6_next_disk(int disk, int raid_disks) -{ - disk++; - return (disk < raid_disks) ? disk : 0; -} - -/* When walking through the disks in a raid5, starting at raid6_d0, - * We need to map each disk to a 'slot', where the data disks are slot - * 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk - * is raid_disks-1. This help does that mapping. - */ -static int raid6_idx_to_slot(int idx, struct stripe_head *sh, - int *count, int syndrome_disks) -{ - int slot = *count; - - if (sh->ddf_layout) - (*count)++; - if (idx == sh->pd_idx) - return syndrome_disks; - if (idx == sh->qd_idx) - return syndrome_disks + 1; - if (!sh->ddf_layout) - (*count)++; - return slot; -} - -static void return_io(struct bio *return_bi) -{ - struct bio *bi = return_bi; - while (bi) { - - return_bi = bi->bi_next; - bi->bi_next = NULL; - bi->bi_size = 0; - bio_endio(bi, 0); - bi = return_bi; - } -} - -static void print_raid5_conf (struct r5conf *conf); - -static int stripe_operations_active(struct stripe_head *sh) -{ - return sh->check_state || sh->reconstruct_state || - test_bit(STRIPE_BIOFILL_RUN, &sh->state) || - test_bit(STRIPE_COMPUTE_RUN, &sh->state); -} - -static void __release_stripe(struct r5conf *conf, struct stripe_head *sh) -{ - if (atomic_dec_and_test(&sh->count)) { - BUG_ON(!list_empty(&sh->lru)); - BUG_ON(atomic_read(&conf->active_stripes)==0); - if (test_bit(STRIPE_HANDLE, &sh->state)) { - if (test_bit(STRIPE_DELAYED, &sh->state) && - !test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) - list_add_tail(&sh->lru, &conf->delayed_list); - else if (test_bit(STRIPE_BIT_DELAY, &sh->state) && - sh->bm_seq - conf->seq_write > 0) - list_add_tail(&sh->lru, &conf->bitmap_list); - else { - clear_bit(STRIPE_DELAYED, &sh->state); - clear_bit(STRIPE_BIT_DELAY, &sh->state); - list_add_tail(&sh->lru, &conf->handle_list); - } - md_wakeup_thread(conf->mddev->thread); - } else { - BUG_ON(stripe_operations_active(sh)); - if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) - if (atomic_dec_return(&conf->preread_active_stripes) - < IO_THRESHOLD) - md_wakeup_thread(conf->mddev->thread); - atomic_dec(&conf->active_stripes); - if (!test_bit(STRIPE_EXPANDING, &sh->state)) { - list_add_tail(&sh->lru, &conf->inactive_list); - wake_up(&conf->wait_for_stripe); - if (conf->retry_read_aligned) - md_wakeup_thread(conf->mddev->thread); - } - } - } -} - -static void release_stripe(struct stripe_head *sh) -{ - struct r5conf *conf = sh->raid_conf; - unsigned long flags; - - spin_lock_irqsave(&conf->device_lock, flags); - __release_stripe(conf, sh); - spin_unlock_irqrestore(&conf->device_lock, flags); -} - -static inline void remove_hash(struct stripe_head *sh) -{ - pr_debug("remove_hash(), stripe %llu\n", - (unsigned long long)sh->sector); - - hlist_del_init(&sh->hash); -} - -static inline void insert_hash(struct r5conf *conf, struct stripe_head *sh) -{ - struct hlist_head *hp = stripe_hash(conf, sh->sector); - - pr_debug("insert_hash(), stripe %llu\n", - (unsigned long long)sh->sector); - - hlist_add_head(&sh->hash, hp); -} - - -/* find an idle stripe, make sure it is unhashed, and return it. */ -static struct stripe_head *get_free_stripe(struct r5conf *conf) -{ - struct stripe_head *sh = NULL; - struct list_head *first; - - if (list_empty(&conf->inactive_list)) - goto out; - first = conf->inactive_list.next; - sh = list_entry(first, struct stripe_head, lru); - list_del_init(first); - remove_hash(sh); - atomic_inc(&conf->active_stripes); -out: - return sh; -} - -static void shrink_buffers(struct stripe_head *sh) -{ - struct page *p; - int i; - int num = sh->raid_conf->pool_size; - - for (i = 0; i < num ; i++) { - p = sh->dev[i].page; - if (!p) - continue; - sh->dev[i].page = NULL; - put_page(p); - } -} - -static int grow_buffers(struct stripe_head *sh) -{ - int i; - int num = sh->raid_conf->pool_size; - - for (i = 0; i < num; i++) { - struct page *page; - - if (!(page = alloc_page(GFP_KERNEL))) { - return 1; - } - sh->dev[i].page = page; - } - return 0; -} - -static void raid5_build_block(struct stripe_head *sh, int i, int previous); -static void stripe_set_idx(sector_t stripe, struct r5conf *conf, int previous, - struct stripe_head *sh); - -static void init_stripe(struct stripe_head *sh, sector_t sector, int previous) -{ - struct r5conf *conf = sh->raid_conf; - int i; - - BUG_ON(atomic_read(&sh->count) != 0); - BUG_ON(test_bit(STRIPE_HANDLE, &sh->state)); - BUG_ON(stripe_operations_active(sh)); - - pr_debug("init_stripe called, stripe %llu\n", - (unsigned long long)sh->sector); - - remove_hash(sh); - - sh->generation = conf->generation - previous; - sh->disks = previous ? conf->previous_raid_disks : conf->raid_disks; - sh->sector = sector; - stripe_set_idx(sector, conf, previous, sh); - sh->state = 0; - - - for (i = sh->disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - - if (dev->toread || dev->read || dev->towrite || dev->written || - test_bit(R5_LOCKED, &dev->flags)) { - printk(KERN_ERR "sector=%llx i=%d %p %p %p %p %d\n", - (unsigned long long)sh->sector, i, dev->toread, - dev->read, dev->towrite, dev->written, - test_bit(R5_LOCKED, &dev->flags)); - WARN_ON(1); - } - dev->flags = 0; - raid5_build_block(sh, i, previous); - } - insert_hash(conf, sh); -} - -static struct stripe_head *__find_stripe(struct r5conf *conf, sector_t sector, - short generation) -{ - struct stripe_head *sh; - struct hlist_node *hn; - - pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector); - hlist_for_each_entry(sh, hn, stripe_hash(conf, sector), hash) - if (sh->sector == sector && sh->generation == generation) - return sh; - pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector); - return NULL; -} - -/* - * Need to check if array has failed when deciding whether to: - * - start an array - * - remove non-faulty devices - * - add a spare - * - allow a reshape - * This determination is simple when no reshape is happening. - * However if there is a reshape, we need to carefully check - * both the before and after sections. - * This is because some failed devices may only affect one - * of the two sections, and some non-in_sync devices may - * be insync in the section most affected by failed devices. - */ -static int calc_degraded(struct r5conf *conf) -{ - int degraded, degraded2; - int i; - - rcu_read_lock(); - degraded = 0; - for (i = 0; i < conf->previous_raid_disks; i++) { - struct md_rdev *rdev = rcu_dereference(conf->disks[i].rdev); - if (!rdev || test_bit(Faulty, &rdev->flags)) - degraded++; - else if (test_bit(In_sync, &rdev->flags)) - ; - else - /* not in-sync or faulty. - * If the reshape increases the number of devices, - * this is being recovered by the reshape, so - * this 'previous' section is not in_sync. - * If the number of devices is being reduced however, - * the device can only be part of the array if - * we are reverting a reshape, so this section will - * be in-sync. - */ - if (conf->raid_disks >= conf->previous_raid_disks) - degraded++; - } - rcu_read_unlock(); - if (conf->raid_disks == conf->previous_raid_disks) - return degraded; - rcu_read_lock(); - degraded2 = 0; - for (i = 0; i < conf->raid_disks; i++) { - struct md_rdev *rdev = rcu_dereference(conf->disks[i].rdev); - if (!rdev || test_bit(Faulty, &rdev->flags)) - degraded2++; - else if (test_bit(In_sync, &rdev->flags)) - ; - else - /* not in-sync or faulty. - * If reshape increases the number of devices, this - * section has already been recovered, else it - * almost certainly hasn't. - */ - if (conf->raid_disks <= conf->previous_raid_disks) - degraded2++; - } - rcu_read_unlock(); - if (degraded2 > degraded) - return degraded2; - return degraded; -} - -static int has_failed(struct r5conf *conf) -{ - int degraded; - - if (conf->mddev->reshape_position == MaxSector) - return conf->mddev->degraded > conf->max_degraded; - - degraded = calc_degraded(conf); - if (degraded > conf->max_degraded) - return 1; - return 0; -} - -static struct stripe_head * -get_active_stripe(struct r5conf *conf, sector_t sector, - int previous, int noblock, int noquiesce) -{ - struct stripe_head *sh; - - pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector); - - spin_lock_irq(&conf->device_lock); - - do { - wait_event_lock_irq(conf->wait_for_stripe, - conf->quiesce == 0 || noquiesce, - conf->device_lock, /* nothing */); - sh = __find_stripe(conf, sector, conf->generation - previous); - if (!sh) { - if (!conf->inactive_blocked) - sh = get_free_stripe(conf); - if (noblock && sh == NULL) - break; - if (!sh) { - conf->inactive_blocked = 1; - wait_event_lock_irq(conf->wait_for_stripe, - !list_empty(&conf->inactive_list) && - (atomic_read(&conf->active_stripes) - < (conf->max_nr_stripes *3/4) - || !conf->inactive_blocked), - conf->device_lock, - ); - conf->inactive_blocked = 0; - } else - init_stripe(sh, sector, previous); - } else { - if (atomic_read(&sh->count)) { - BUG_ON(!list_empty(&sh->lru) - && !test_bit(STRIPE_EXPANDING, &sh->state)); - } else { - if (!test_bit(STRIPE_HANDLE, &sh->state)) - atomic_inc(&conf->active_stripes); - if (list_empty(&sh->lru) && - !test_bit(STRIPE_EXPANDING, &sh->state)) - BUG(); - list_del_init(&sh->lru); - } - } - } while (sh == NULL); - - if (sh) - atomic_inc(&sh->count); - - spin_unlock_irq(&conf->device_lock); - return sh; -} - -static void -raid5_end_read_request(struct bio *bi, int error); -static void -raid5_end_write_request(struct bio *bi, int error); - -static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s) -{ - struct r5conf *conf = sh->raid_conf; - int i, disks = sh->disks; - - might_sleep(); - - for (i = disks; i--; ) { - int rw; - int replace_only = 0; - struct bio *bi, *rbi; - struct md_rdev *rdev, *rrdev = NULL; - if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) { - if (test_and_clear_bit(R5_WantFUA, &sh->dev[i].flags)) - rw = WRITE_FUA; - else - rw = WRITE; - } else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags)) - rw = READ; - else if (test_and_clear_bit(R5_WantReplace, - &sh->dev[i].flags)) { - rw = WRITE; - replace_only = 1; - } else - continue; - - bi = &sh->dev[i].req; - rbi = &sh->dev[i].rreq; /* For writing to replacement */ - - bi->bi_rw = rw; - rbi->bi_rw = rw; - if (rw & WRITE) { - bi->bi_end_io = raid5_end_write_request; - rbi->bi_end_io = raid5_end_write_request; - } else - bi->bi_end_io = raid5_end_read_request; - - rcu_read_lock(); - rrdev = rcu_dereference(conf->disks[i].replacement); - smp_mb(); /* Ensure that if rrdev is NULL, rdev won't be */ - rdev = rcu_dereference(conf->disks[i].rdev); - if (!rdev) { - rdev = rrdev; - rrdev = NULL; - } - if (rw & WRITE) { - if (replace_only) - rdev = NULL; - if (rdev == rrdev) - /* We raced and saw duplicates */ - rrdev = NULL; - } else { - if (test_bit(R5_ReadRepl, &sh->dev[i].flags) && rrdev) - rdev = rrdev; - rrdev = NULL; - } - - if (rdev && test_bit(Faulty, &rdev->flags)) - rdev = NULL; - if (rdev) - atomic_inc(&rdev->nr_pending); - if (rrdev && test_bit(Faulty, &rrdev->flags)) - rrdev = NULL; - if (rrdev) - atomic_inc(&rrdev->nr_pending); - rcu_read_unlock(); - - /* We have already checked bad blocks for reads. Now - * need to check for writes. We never accept write errors - * on the replacement, so we don't to check rrdev. - */ - while ((rw & WRITE) && rdev && - test_bit(WriteErrorSeen, &rdev->flags)) { - sector_t first_bad; - int bad_sectors; - int bad = is_badblock(rdev, sh->sector, STRIPE_SECTORS, - &first_bad, &bad_sectors); - if (!bad) - break; - - if (bad < 0) { - set_bit(BlockedBadBlocks, &rdev->flags); - if (!conf->mddev->external && - conf->mddev->flags) { - /* It is very unlikely, but we might - * still need to write out the - * bad block log - better give it - * a chance*/ - md_check_recovery(conf->mddev); - } - /* - * Because md_wait_for_blocked_rdev - * will dec nr_pending, we must - * increment it first. - */ - atomic_inc(&rdev->nr_pending); - md_wait_for_blocked_rdev(rdev, conf->mddev); - } else { - /* Acknowledged bad block - skip the write */ - rdev_dec_pending(rdev, conf->mddev); - rdev = NULL; - } - } - - if (rdev) { - if (s->syncing || s->expanding || s->expanded - || s->replacing) - md_sync_acct(rdev->bdev, STRIPE_SECTORS); - - set_bit(STRIPE_IO_STARTED, &sh->state); - - bi->bi_bdev = rdev->bdev; - pr_debug("%s: for %llu schedule op %ld on disc %d\n", - __func__, (unsigned long long)sh->sector, - bi->bi_rw, i); - atomic_inc(&sh->count); - bi->bi_sector = sh->sector + rdev->data_offset; - bi->bi_flags = 1 << BIO_UPTODATE; - bi->bi_idx = 0; - bi->bi_io_vec[0].bv_len = STRIPE_SIZE; - bi->bi_io_vec[0].bv_offset = 0; - bi->bi_size = STRIPE_SIZE; - bi->bi_next = NULL; - if (rrdev) - set_bit(R5_DOUBLE_LOCKED, &sh->dev[i].flags); - generic_make_request(bi); - } - if (rrdev) { - if (s->syncing || s->expanding || s->expanded - || s->replacing) - md_sync_acct(rrdev->bdev, STRIPE_SECTORS); - - set_bit(STRIPE_IO_STARTED, &sh->state); - - rbi->bi_bdev = rrdev->bdev; - pr_debug("%s: for %llu schedule op %ld on " - "replacement disc %d\n", - __func__, (unsigned long long)sh->sector, - rbi->bi_rw, i); - atomic_inc(&sh->count); - rbi->bi_sector = sh->sector + rrdev->data_offset; - rbi->bi_flags = 1 << BIO_UPTODATE; - rbi->bi_idx = 0; - rbi->bi_io_vec[0].bv_len = STRIPE_SIZE; - rbi->bi_io_vec[0].bv_offset = 0; - rbi->bi_size = STRIPE_SIZE; - rbi->bi_next = NULL; - generic_make_request(rbi); - } - if (!rdev && !rrdev) { - if (rw & WRITE) - set_bit(STRIPE_DEGRADED, &sh->state); - pr_debug("skip op %ld on disc %d for sector %llu\n", - bi->bi_rw, i, (unsigned long long)sh->sector); - clear_bit(R5_LOCKED, &sh->dev[i].flags); - set_bit(STRIPE_HANDLE, &sh->state); - } - } -} - -static struct dma_async_tx_descriptor * -async_copy_data(int frombio, struct bio *bio, struct page *page, - sector_t sector, struct dma_async_tx_descriptor *tx) -{ - struct bio_vec *bvl; - struct page *bio_page; - int i; - int page_offset; - struct async_submit_ctl submit; - enum async_tx_flags flags = 0; - - if (bio->bi_sector >= sector) - page_offset = (signed)(bio->bi_sector - sector) * 512; - else - page_offset = (signed)(sector - bio->bi_sector) * -512; - - if (frombio) - flags |= ASYNC_TX_FENCE; - init_async_submit(&submit, flags, tx, NULL, NULL, NULL); - - bio_for_each_segment(bvl, bio, i) { - int len = bvl->bv_len; - int clen; - int b_offset = 0; - - if (page_offset < 0) { - b_offset = -page_offset; - page_offset += b_offset; - len -= b_offset; - } - - if (len > 0 && page_offset + len > STRIPE_SIZE) - clen = STRIPE_SIZE - page_offset; - else - clen = len; - - if (clen > 0) { - b_offset += bvl->bv_offset; - bio_page = bvl->bv_page; - if (frombio) - tx = async_memcpy(page, bio_page, page_offset, - b_offset, clen, &submit); - else - tx = async_memcpy(bio_page, page, b_offset, - page_offset, clen, &submit); - } - /* chain the operations */ - submit.depend_tx = tx; - - if (clen < len) /* hit end of page */ - break; - page_offset += len; - } - - return tx; -} - -static void ops_complete_biofill(void *stripe_head_ref) -{ - struct stripe_head *sh = stripe_head_ref; - struct bio *return_bi = NULL; - struct r5conf *conf = sh->raid_conf; - int i; - - pr_debug("%s: stripe %llu\n", __func__, - (unsigned long long)sh->sector); - - /* clear completed biofills */ - spin_lock_irq(&conf->device_lock); - for (i = sh->disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - - /* acknowledge completion of a biofill operation */ - /* and check if we need to reply to a read request, - * new R5_Wantfill requests are held off until - * !STRIPE_BIOFILL_RUN - */ - if (test_and_clear_bit(R5_Wantfill, &dev->flags)) { - struct bio *rbi, *rbi2; - - BUG_ON(!dev->read); - rbi = dev->read; - dev->read = NULL; - while (rbi && rbi->bi_sector < - dev->sector + STRIPE_SECTORS) { - rbi2 = r5_next_bio(rbi, dev->sector); - if (!raid5_dec_bi_phys_segments(rbi)) { - rbi->bi_next = return_bi; - return_bi = rbi; - } - rbi = rbi2; - } - } - } - spin_unlock_irq(&conf->device_lock); - clear_bit(STRIPE_BIOFILL_RUN, &sh->state); - - return_io(return_bi); - - set_bit(STRIPE_HANDLE, &sh->state); - release_stripe(sh); -} - -static void ops_run_biofill(struct stripe_head *sh) -{ - struct dma_async_tx_descriptor *tx = NULL; - struct r5conf *conf = sh->raid_conf; - struct async_submit_ctl submit; - int i; - - pr_debug("%s: stripe %llu\n", __func__, - (unsigned long long)sh->sector); - - for (i = sh->disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - if (test_bit(R5_Wantfill, &dev->flags)) { - struct bio *rbi; - spin_lock_irq(&conf->device_lock); - dev->read = rbi = dev->toread; - dev->toread = NULL; - spin_unlock_irq(&conf->device_lock); - while (rbi && rbi->bi_sector < - dev->sector + STRIPE_SECTORS) { - tx = async_copy_data(0, rbi, dev->page, - dev->sector, tx); - rbi = r5_next_bio(rbi, dev->sector); - } - } - } - - atomic_inc(&sh->count); - init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_biofill, sh, NULL); - async_trigger_callback(&submit); -} - -static void mark_target_uptodate(struct stripe_head *sh, int target) -{ - struct r5dev *tgt; - - if (target < 0) - return; - - tgt = &sh->dev[target]; - set_bit(R5_UPTODATE, &tgt->flags); - BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); - clear_bit(R5_Wantcompute, &tgt->flags); -} - -static void ops_complete_compute(void *stripe_head_ref) -{ - struct stripe_head *sh = stripe_head_ref; - - pr_debug("%s: stripe %llu\n", __func__, - (unsigned long long)sh->sector); - - /* mark the computed target(s) as uptodate */ - mark_target_uptodate(sh, sh->ops.target); - mark_target_uptodate(sh, sh->ops.target2); - - clear_bit(STRIPE_COMPUTE_RUN, &sh->state); - if (sh->check_state == check_state_compute_run) - sh->check_state = check_state_compute_result; - set_bit(STRIPE_HANDLE, &sh->state); - release_stripe(sh); -} - -/* return a pointer to the address conversion region of the scribble buffer */ -static addr_conv_t *to_addr_conv(struct stripe_head *sh, - struct raid5_percpu *percpu) -{ - return percpu->scribble + sizeof(struct page *) * (sh->disks + 2); -} - -static struct dma_async_tx_descriptor * -ops_run_compute5(struct stripe_head *sh, struct raid5_percpu *percpu) -{ - int disks = sh->disks; - struct page **xor_srcs = percpu->scribble; - int target = sh->ops.target; - struct r5dev *tgt = &sh->dev[target]; - struct page *xor_dest = tgt->page; - int count = 0; - struct dma_async_tx_descriptor *tx; - struct async_submit_ctl submit; - int i; - - pr_debug("%s: stripe %llu block: %d\n", - __func__, (unsigned long long)sh->sector, target); - BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); - - for (i = disks; i--; ) - if (i != target) - xor_srcs[count++] = sh->dev[i].page; - - atomic_inc(&sh->count); - - init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, NULL, - ops_complete_compute, sh, to_addr_conv(sh, percpu)); - if (unlikely(count == 1)) - tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit); - else - tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit); - - return tx; -} - -/* set_syndrome_sources - populate source buffers for gen_syndrome - * @srcs - (struct page *) array of size sh->disks - * @sh - stripe_head to parse - * - * Populates srcs in proper layout order for the stripe and returns the - * 'count' of sources to be used in a call to async_gen_syndrome. The P - * destination buffer is recorded in srcs[count] and the Q destination - * is recorded in srcs[count+1]]. - */ -static int set_syndrome_sources(struct page **srcs, struct stripe_head *sh) -{ - int disks = sh->disks; - int syndrome_disks = sh->ddf_layout ? disks : (disks - 2); - int d0_idx = raid6_d0(sh); - int count; - int i; - - for (i = 0; i < disks; i++) - srcs[i] = NULL; - - count = 0; - i = d0_idx; - do { - int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks); - - srcs[slot] = sh->dev[i].page; - i = raid6_next_disk(i, disks); - } while (i != d0_idx); - - return syndrome_disks; -} - -static struct dma_async_tx_descriptor * -ops_run_compute6_1(struct stripe_head *sh, struct raid5_percpu *percpu) -{ - int disks = sh->disks; - struct page **blocks = percpu->scribble; - int target; - int qd_idx = sh->qd_idx; - struct dma_async_tx_descriptor *tx; - struct async_submit_ctl submit; - struct r5dev *tgt; - struct page *dest; - int i; - int count; - - if (sh->ops.target < 0) - target = sh->ops.target2; - else if (sh->ops.target2 < 0) - target = sh->ops.target; - else - /* we should only have one valid target */ - BUG(); - BUG_ON(target < 0); - pr_debug("%s: stripe %llu block: %d\n", - __func__, (unsigned long long)sh->sector, target); - - tgt = &sh->dev[target]; - BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); - dest = tgt->page; - - atomic_inc(&sh->count); - - if (target == qd_idx) { - count = set_syndrome_sources(blocks, sh); - blocks[count] = NULL; /* regenerating p is not necessary */ - BUG_ON(blocks[count+1] != dest); /* q should already be set */ - init_async_submit(&submit, ASYNC_TX_FENCE, NULL, - ops_complete_compute, sh, - to_addr_conv(sh, percpu)); - tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit); - } else { - /* Compute any data- or p-drive using XOR */ - count = 0; - for (i = disks; i-- ; ) { - if (i == target || i == qd_idx) - continue; - blocks[count++] = sh->dev[i].page; - } - - init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, - NULL, ops_complete_compute, sh, - to_addr_conv(sh, percpu)); - tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE, &submit); - } - - return tx; -} - -static struct dma_async_tx_descriptor * -ops_run_compute6_2(struct stripe_head *sh, struct raid5_percpu *percpu) -{ - int i, count, disks = sh->disks; - int syndrome_disks = sh->ddf_layout ? disks : disks-2; - int d0_idx = raid6_d0(sh); - int faila = -1, failb = -1; - int target = sh->ops.target; - int target2 = sh->ops.target2; - struct r5dev *tgt = &sh->dev[target]; - struct r5dev *tgt2 = &sh->dev[target2]; - struct dma_async_tx_descriptor *tx; - struct page **blocks = percpu->scribble; - struct async_submit_ctl submit; - - pr_debug("%s: stripe %llu block1: %d block2: %d\n", - __func__, (unsigned long long)sh->sector, target, target2); - BUG_ON(target < 0 || target2 < 0); - BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); - BUG_ON(!test_bit(R5_Wantcompute, &tgt2->flags)); - - /* we need to open-code set_syndrome_sources to handle the - * slot number conversion for 'faila' and 'failb' - */ - for (i = 0; i < disks ; i++) - blocks[i] = NULL; - count = 0; - i = d0_idx; - do { - int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks); - - blocks[slot] = sh->dev[i].page; - - if (i == target) - faila = slot; - if (i == target2) - failb = slot; - i = raid6_next_disk(i, disks); - } while (i != d0_idx); - - BUG_ON(faila == failb); - if (failb < faila) - swap(faila, failb); - pr_debug("%s: stripe: %llu faila: %d failb: %d\n", - __func__, (unsigned long long)sh->sector, faila, failb); - - atomic_inc(&sh->count); - - if (failb == syndrome_disks+1) { - /* Q disk is one of the missing disks */ - if (faila == syndrome_disks) { - /* Missing P+Q, just recompute */ - init_async_submit(&submit, ASYNC_TX_FENCE, NULL, - ops_complete_compute, sh, - to_addr_conv(sh, percpu)); - return async_gen_syndrome(blocks, 0, syndrome_disks+2, - STRIPE_SIZE, &submit); - } else { - struct page *dest; - int data_target; - int qd_idx = sh->qd_idx; - - /* Missing D+Q: recompute D from P, then recompute Q */ - if (target == qd_idx) - data_target = target2; - else - data_target = target; - - count = 0; - for (i = disks; i-- ; ) { - if (i == data_target || i == qd_idx) - continue; - blocks[count++] = sh->dev[i].page; - } - dest = sh->dev[data_target].page; - init_async_submit(&submit, - ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, - NULL, NULL, NULL, - to_addr_conv(sh, percpu)); - tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE, - &submit); - - count = set_syndrome_sources(blocks, sh); - init_async_submit(&submit, ASYNC_TX_FENCE, tx, - ops_complete_compute, sh, - to_addr_conv(sh, percpu)); - return async_gen_syndrome(blocks, 0, count+2, - STRIPE_SIZE, &submit); - } - } else { - init_async_submit(&submit, ASYNC_TX_FENCE, NULL, - ops_complete_compute, sh, - to_addr_conv(sh, percpu)); - if (failb == syndrome_disks) { - /* We're missing D+P. */ - return async_raid6_datap_recov(syndrome_disks+2, - STRIPE_SIZE, faila, - blocks, &submit); - } else { - /* We're missing D+D. */ - return async_raid6_2data_recov(syndrome_disks+2, - STRIPE_SIZE, faila, failb, - blocks, &submit); - } - } -} - - -static void ops_complete_prexor(void *stripe_head_ref) -{ - struct stripe_head *sh = stripe_head_ref; - - pr_debug("%s: stripe %llu\n", __func__, - (unsigned long long)sh->sector); -} - -static struct dma_async_tx_descriptor * -ops_run_prexor(struct stripe_head *sh, struct raid5_percpu *percpu, - struct dma_async_tx_descriptor *tx) -{ - int disks = sh->disks; - struct page **xor_srcs = percpu->scribble; - int count = 0, pd_idx = sh->pd_idx, i; - struct async_submit_ctl submit; - - /* existing parity data subtracted */ - struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; - - pr_debug("%s: stripe %llu\n", __func__, - (unsigned long long)sh->sector); - - for (i = disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - /* Only process blocks that are known to be uptodate */ - if (test_bit(R5_Wantdrain, &dev->flags)) - xor_srcs[count++] = dev->page; - } - - init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, - ops_complete_prexor, sh, to_addr_conv(sh, percpu)); - tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit); - - return tx; -} - -static struct dma_async_tx_descriptor * -ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) -{ - int disks = sh->disks; - int i; - - pr_debug("%s: stripe %llu\n", __func__, - (unsigned long long)sh->sector); - - for (i = disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - struct bio *chosen; - - if (test_and_clear_bit(R5_Wantdrain, &dev->flags)) { - struct bio *wbi; - - spin_lock_irq(&sh->raid_conf->device_lock); - chosen = dev->towrite; - dev->towrite = NULL; - BUG_ON(dev->written); - wbi = dev->written = chosen; - spin_unlock_irq(&sh->raid_conf->device_lock); - - while (wbi && wbi->bi_sector < - dev->sector + STRIPE_SECTORS) { - if (wbi->bi_rw & REQ_FUA) - set_bit(R5_WantFUA, &dev->flags); - tx = async_copy_data(1, wbi, dev->page, - dev->sector, tx); - wbi = r5_next_bio(wbi, dev->sector); - } - } - } - - return tx; -} - -static void ops_complete_reconstruct(void *stripe_head_ref) -{ - struct stripe_head *sh = stripe_head_ref; - int disks = sh->disks; - int pd_idx = sh->pd_idx; - int qd_idx = sh->qd_idx; - int i; - bool fua = false; - - pr_debug("%s: stripe %llu\n", __func__, - (unsigned long long)sh->sector); - - for (i = disks; i--; ) - fua |= test_bit(R5_WantFUA, &sh->dev[i].flags); - - for (i = disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - - if (dev->written || i == pd_idx || i == qd_idx) { - set_bit(R5_UPTODATE, &dev->flags); - if (fua) - set_bit(R5_WantFUA, &dev->flags); - } - } - - if (sh->reconstruct_state == reconstruct_state_drain_run) - sh->reconstruct_state = reconstruct_state_drain_result; - else if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) - sh->reconstruct_state = reconstruct_state_prexor_drain_result; - else { - BUG_ON(sh->reconstruct_state != reconstruct_state_run); - sh->reconstruct_state = reconstruct_state_result; - } - - set_bit(STRIPE_HANDLE, &sh->state); - release_stripe(sh); -} - -static void -ops_run_reconstruct5(struct stripe_head *sh, struct raid5_percpu *percpu, - struct dma_async_tx_descriptor *tx) -{ - int disks = sh->disks; - struct page **xor_srcs = percpu->scribble; - struct async_submit_ctl submit; - int count = 0, pd_idx = sh->pd_idx, i; - struct page *xor_dest; - int prexor = 0; - unsigned long flags; - - pr_debug("%s: stripe %llu\n", __func__, - (unsigned long long)sh->sector); - - /* check if prexor is active which means only process blocks - * that are part of a read-modify-write (written) - */ - if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) { - prexor = 1; - xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; - for (i = disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - if (dev->written) - xor_srcs[count++] = dev->page; - } - } else { - xor_dest = sh->dev[pd_idx].page; - for (i = disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - if (i != pd_idx) - xor_srcs[count++] = dev->page; - } - } - - /* 1/ if we prexor'd then the dest is reused as a source - * 2/ if we did not prexor then we are redoing the parity - * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST - * for the synchronous xor case - */ - flags = ASYNC_TX_ACK | - (prexor ? ASYNC_TX_XOR_DROP_DST : ASYNC_TX_XOR_ZERO_DST); - - atomic_inc(&sh->count); - - init_async_submit(&submit, flags, tx, ops_complete_reconstruct, sh, - to_addr_conv(sh, percpu)); - if (unlikely(count == 1)) - tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit); - else - tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit); -} - -static void -ops_run_reconstruct6(struct stripe_head *sh, struct raid5_percpu *percpu, - struct dma_async_tx_descriptor *tx) -{ - struct async_submit_ctl submit; - struct page **blocks = percpu->scribble; - int count; - - pr_debug("%s: stripe %llu\n", __func__, (unsigned long long)sh->sector); - - count = set_syndrome_sources(blocks, sh); - - atomic_inc(&sh->count); - - init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_reconstruct, - sh, to_addr_conv(sh, percpu)); - async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit); -} - -static void ops_complete_check(void *stripe_head_ref) -{ - struct stripe_head *sh = stripe_head_ref; - - pr_debug("%s: stripe %llu\n", __func__, - (unsigned long long)sh->sector); - - sh->check_state = check_state_check_result; - set_bit(STRIPE_HANDLE, &sh->state); - release_stripe(sh); -} - -static void ops_run_check_p(struct stripe_head *sh, struct raid5_percpu *percpu) -{ - int disks = sh->disks; - int pd_idx = sh->pd_idx; - int qd_idx = sh->qd_idx; - struct page *xor_dest; - struct page **xor_srcs = percpu->scribble; - struct dma_async_tx_descriptor *tx; - struct async_submit_ctl submit; - int count; - int i; - - pr_debug("%s: stripe %llu\n", __func__, - (unsigned long long)sh->sector); - - count = 0; - xor_dest = sh->dev[pd_idx].page; - xor_srcs[count++] = xor_dest; - for (i = disks; i--; ) { - if (i == pd_idx || i == qd_idx) - continue; - xor_srcs[count++] = sh->dev[i].page; - } - - init_async_submit(&submit, 0, NULL, NULL, NULL, - to_addr_conv(sh, percpu)); - tx = async_xor_val(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, - &sh->ops.zero_sum_result, &submit); - - atomic_inc(&sh->count); - init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_check, sh, NULL); - tx = async_trigger_callback(&submit); -} - -static void ops_run_check_pq(struct stripe_head *sh, struct raid5_percpu *percpu, int checkp) -{ - struct page **srcs = percpu->scribble; - struct async_submit_ctl submit; - int count; - - pr_debug("%s: stripe %llu checkp: %d\n", __func__, - (unsigned long long)sh->sector, checkp); - - count = set_syndrome_sources(srcs, sh); - if (!checkp) - srcs[count] = NULL; - - atomic_inc(&sh->count); - init_async_submit(&submit, ASYNC_TX_ACK, NULL, ops_complete_check, - sh, to_addr_conv(sh, percpu)); - async_syndrome_val(srcs, 0, count+2, STRIPE_SIZE, - &sh->ops.zero_sum_result, percpu->spare_page, &submit); -} - -static void __raid_run_ops(struct stripe_head *sh, unsigned long ops_request) -{ - int overlap_clear = 0, i, disks = sh->disks; - struct dma_async_tx_descriptor *tx = NULL; - struct r5conf *conf = sh->raid_conf; - int level = conf->level; - struct raid5_percpu *percpu; - unsigned long cpu; - - cpu = get_cpu(); - percpu = per_cpu_ptr(conf->percpu, cpu); - if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) { - ops_run_biofill(sh); - overlap_clear++; - } - - if (test_bit(STRIPE_OP_COMPUTE_BLK, &ops_request)) { - if (level < 6) - tx = ops_run_compute5(sh, percpu); - else { - if (sh->ops.target2 < 0 || sh->ops.target < 0) - tx = ops_run_compute6_1(sh, percpu); - else - tx = ops_run_compute6_2(sh, percpu); - } - /* terminate the chain if reconstruct is not set to be run */ - if (tx && !test_bit(STRIPE_OP_RECONSTRUCT, &ops_request)) - async_tx_ack(tx); - } - - if (test_bit(STRIPE_OP_PREXOR, &ops_request)) - tx = ops_run_prexor(sh, percpu, tx); - - if (test_bit(STRIPE_OP_BIODRAIN, &ops_request)) { - tx = ops_run_biodrain(sh, tx); - overlap_clear++; - } - - if (test_bit(STRIPE_OP_RECONSTRUCT, &ops_request)) { - if (level < 6) - ops_run_reconstruct5(sh, percpu, tx); - else - ops_run_reconstruct6(sh, percpu, tx); - } - - if (test_bit(STRIPE_OP_CHECK, &ops_request)) { - if (sh->check_state == check_state_run) - ops_run_check_p(sh, percpu); - else if (sh->check_state == check_state_run_q) - ops_run_check_pq(sh, percpu, 0); - else if (sh->check_state == check_state_run_pq) - ops_run_check_pq(sh, percpu, 1); - else - BUG(); - } - - if (overlap_clear) - for (i = disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - if (test_and_clear_bit(R5_Overlap, &dev->flags)) - wake_up(&sh->raid_conf->wait_for_overlap); - } - put_cpu(); -} - -#ifdef CONFIG_MULTICORE_RAID456 -static void async_run_ops(void *param, async_cookie_t cookie) -{ - struct stripe_head *sh = param; - unsigned long ops_request = sh->ops.request; - - clear_bit_unlock(STRIPE_OPS_REQ_PENDING, &sh->state); - wake_up(&sh->ops.wait_for_ops); - - __raid_run_ops(sh, ops_request); - release_stripe(sh); -} - -static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request) -{ - /* since handle_stripe can be called outside of raid5d context - * we need to ensure sh->ops.request is de-staged before another - * request arrives - */ - wait_event(sh->ops.wait_for_ops, - !test_and_set_bit_lock(STRIPE_OPS_REQ_PENDING, &sh->state)); - sh->ops.request = ops_request; - - atomic_inc(&sh->count); - async_schedule(async_run_ops, sh); -} -#else -#define raid_run_ops __raid_run_ops -#endif - -static int grow_one_stripe(struct r5conf *conf) -{ - struct stripe_head *sh; - sh = kmem_cache_zalloc(conf->slab_cache, GFP_KERNEL); - if (!sh) - return 0; - - sh->raid_conf = conf; - #ifdef CONFIG_MULTICORE_RAID456 - init_waitqueue_head(&sh->ops.wait_for_ops); - #endif - - if (grow_buffers(sh)) { - shrink_buffers(sh); - kmem_cache_free(conf->slab_cache, sh); - return 0; - } - /* we just created an active stripe so... */ - atomic_set(&sh->count, 1); - atomic_inc(&conf->active_stripes); - INIT_LIST_HEAD(&sh->lru); - release_stripe(sh); - return 1; -} - -static int grow_stripes(struct r5conf *conf, int num) -{ - struct kmem_cache *sc; - int devs = max(conf->raid_disks, conf->previous_raid_disks); - - if (conf->mddev->gendisk) - sprintf(conf->cache_name[0], - "raid%d-%s", conf->level, mdname(conf->mddev)); - else - sprintf(conf->cache_name[0], - "raid%d-%p", conf->level, conf->mddev); - sprintf(conf->cache_name[1], "%s-alt", conf->cache_name[0]); - - conf->active_name = 0; - sc = kmem_cache_create(conf->cache_name[conf->active_name], - sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev), - 0, 0, NULL); - if (!sc) - return 1; - conf->slab_cache = sc; - conf->pool_size = devs; - while (num--) - if (!grow_one_stripe(conf)) - return 1; - return 0; -} - -/** - * scribble_len - return the required size of the scribble region - * @num - total number of disks in the array - * - * The size must be enough to contain: - * 1/ a struct page pointer for each device in the array +2 - * 2/ room to convert each entry in (1) to its corresponding dma - * (dma_map_page()) or page (page_address()) address. - * - * Note: the +2 is for the destination buffers of the ddf/raid6 case where we - * calculate over all devices (not just the data blocks), using zeros in place - * of the P and Q blocks. - */ -static size_t scribble_len(int num) -{ - size_t len; - - len = sizeof(struct page *) * (num+2) + sizeof(addr_conv_t) * (num+2); - - return len; -} - -static int resize_stripes(struct r5conf *conf, int newsize) -{ - /* Make all the stripes able to hold 'newsize' devices. - * New slots in each stripe get 'page' set to a new page. - * - * This happens in stages: - * 1/ create a new kmem_cache and allocate the required number of - * stripe_heads. - * 2/ gather all the old stripe_heads and tranfer the pages across - * to the new stripe_heads. This will have the side effect of - * freezing the array as once all stripe_heads have been collected, - * no IO will be possible. Old stripe heads are freed once their - * pages have been transferred over, and the old kmem_cache is - * freed when all stripes are done. - * 3/ reallocate conf->disks to be suitable bigger. If this fails, - * we simple return a failre status - no need to clean anything up. - * 4/ allocate new pages for the new slots in the new stripe_heads. - * If this fails, we don't bother trying the shrink the - * stripe_heads down again, we just leave them as they are. - * As each stripe_head is processed the new one is released into - * active service. - * - * Once step2 is started, we cannot afford to wait for a write, - * so we use GFP_NOIO allocations. - */ - struct stripe_head *osh, *nsh; - LIST_HEAD(newstripes); - struct disk_info *ndisks; - unsigned long cpu; - int err; - struct kmem_cache *sc; - int i; - - if (newsize <= conf->pool_size) - return 0; /* never bother to shrink */ - - err = md_allow_write(conf->mddev); - if (err) - return err; - - /* Step 1 */ - sc = kmem_cache_create(conf->cache_name[1-conf->active_name], - sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev), - 0, 0, NULL); - if (!sc) - return -ENOMEM; - - for (i = conf->max_nr_stripes; i; i--) { - nsh = kmem_cache_zalloc(sc, GFP_KERNEL); - if (!nsh) - break; - - nsh->raid_conf = conf; - #ifdef CONFIG_MULTICORE_RAID456 - init_waitqueue_head(&nsh->ops.wait_for_ops); - #endif - - list_add(&nsh->lru, &newstripes); - } - if (i) { - /* didn't get enough, give up */ - while (!list_empty(&newstripes)) { - nsh = list_entry(newstripes.next, struct stripe_head, lru); - list_del(&nsh->lru); - kmem_cache_free(sc, nsh); - } - kmem_cache_destroy(sc); - return -ENOMEM; - } - /* Step 2 - Must use GFP_NOIO now. - * OK, we have enough stripes, start collecting inactive - * stripes and copying them over - */ - list_for_each_entry(nsh, &newstripes, lru) { - spin_lock_irq(&conf->device_lock); - wait_event_lock_irq(conf->wait_for_stripe, - !list_empty(&conf->inactive_list), - conf->device_lock, - ); - osh = get_free_stripe(conf); - spin_unlock_irq(&conf->device_lock); - atomic_set(&nsh->count, 1); - for(i=0; i<conf->pool_size; i++) - nsh->dev[i].page = osh->dev[i].page; - for( ; i<newsize; i++) - nsh->dev[i].page = NULL; - kmem_cache_free(conf->slab_cache, osh); - } - kmem_cache_destroy(conf->slab_cache); - - /* Step 3. - * At this point, we are holding all the stripes so the array - * is completely stalled, so now is a good time to resize - * conf->disks and the scribble region - */ - ndisks = kzalloc(newsize * sizeof(struct disk_info), GFP_NOIO); - if (ndisks) { - for (i=0; i<conf->raid_disks; i++) - ndisks[i] = conf->disks[i]; - kfree(conf->disks); - conf->disks = ndisks; - } else - err = -ENOMEM; - - get_online_cpus(); - conf->scribble_len = scribble_len(newsize); - for_each_present_cpu(cpu) { - struct raid5_percpu *percpu; - void *scribble; - - percpu = per_cpu_ptr(conf->percpu, cpu); - scribble = kmalloc(conf->scribble_len, GFP_NOIO); - - if (scribble) { - kfree(percpu->scribble); - percpu->scribble = scribble; - } else { - err = -ENOMEM; - break; - } - } - put_online_cpus(); - - /* Step 4, return new stripes to service */ - while(!list_empty(&newstripes)) { - nsh = list_entry(newstripes.next, struct stripe_head, lru); - list_del_init(&nsh->lru); - - for (i=conf->raid_disks; i < newsize; i++) - if (nsh->dev[i].page == NULL) { - struct page *p = alloc_page(GFP_NOIO); - nsh->dev[i].page = p; - if (!p) - err = -ENOMEM; - } - release_stripe(nsh); - } - /* critical section pass, GFP_NOIO no longer needed */ - - conf->slab_cache = sc; - conf->active_name = 1-conf->active_name; - conf->pool_size = newsize; - return err; -} - -static int drop_one_stripe(struct r5conf *conf) -{ - struct stripe_head *sh; - - spin_lock_irq(&conf->device_lock); - sh = get_free_stripe(conf); - spin_unlock_irq(&conf->device_lock); - if (!sh) - return 0; - BUG_ON(atomic_read(&sh->count)); - shrink_buffers(sh); - kmem_cache_free(conf->slab_cache, sh); - atomic_dec(&conf->active_stripes); - return 1; -} - -static void shrink_stripes(struct r5conf *conf) -{ - while (drop_one_stripe(conf)) - ; - - if (conf->slab_cache) - kmem_cache_destroy(conf->slab_cache); - conf->slab_cache = NULL; -} - -static void raid5_end_read_request(struct bio * bi, int error) -{ - struct stripe_head *sh = bi->bi_private; - struct r5conf *conf = sh->raid_conf; - int disks = sh->disks, i; - int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); - char b[BDEVNAME_SIZE]; - struct md_rdev *rdev = NULL; - - - for (i=0 ; i<disks; i++) - if (bi == &sh->dev[i].req) - break; - - pr_debug("end_read_request %llu/%d, count: %d, uptodate %d.\n", - (unsigned long long)sh->sector, i, atomic_read(&sh->count), - uptodate); - if (i == disks) { - BUG(); - return; - } - if (test_bit(R5_ReadRepl, &sh->dev[i].flags)) - /* If replacement finished while this request was outstanding, - * 'replacement' might be NULL already. - * In that case it moved down to 'rdev'. - * rdev is not removed until all requests are finished. - */ - rdev = conf->disks[i].replacement; - if (!rdev) - rdev = conf->disks[i].rdev; - - if (uptodate) { - set_bit(R5_UPTODATE, &sh->dev[i].flags); - if (test_bit(R5_ReadError, &sh->dev[i].flags)) { - /* Note that this cannot happen on a - * replacement device. We just fail those on - * any error - */ - printk_ratelimited( - KERN_INFO - "md/raid:%s: read error corrected" - " (%lu sectors at %llu on %s)\n", - mdname(conf->mddev), STRIPE_SECTORS, - (unsigned long long)(sh->sector - + rdev->data_offset), - bdevname(rdev->bdev, b)); - atomic_add(STRIPE_SECTORS, &rdev->corrected_errors); - clear_bit(R5_ReadError, &sh->dev[i].flags); - clear_bit(R5_ReWrite, &sh->dev[i].flags); - } - if (atomic_read(&rdev->read_errors)) - atomic_set(&rdev->read_errors, 0); - } else { - const char *bdn = bdevname(rdev->bdev, b); - int retry = 0; - - clear_bit(R5_UPTODATE, &sh->dev[i].flags); - atomic_inc(&rdev->read_errors); - if (test_bit(R5_ReadRepl, &sh->dev[i].flags)) - printk_ratelimited( - KERN_WARNING - "md/raid:%s: read error on replacement device " - "(sector %llu on %s).\n", - mdname(conf->mddev), - (unsigned long long)(sh->sector - + rdev->data_offset), - bdn); - else if (conf->mddev->degraded >= conf->max_degraded) - printk_ratelimited( - KERN_WARNING - "md/raid:%s: read error not correctable " - "(sector %llu on %s).\n", - mdname(conf->mddev), - (unsigned long long)(sh->sector - + rdev->data_offset), - bdn); - else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) - /* Oh, no!!! */ - printk_ratelimited( - KERN_WARNING - "md/raid:%s: read error NOT corrected!! " - "(sector %llu on %s).\n", - mdname(conf->mddev), - (unsigned long long)(sh->sector - + rdev->data_offset), - bdn); - else if (atomic_read(&rdev->read_errors) - > conf->max_nr_stripes) - printk(KERN_WARNING - "md/raid:%s: Too many read errors, failing device %s.\n", - mdname(conf->mddev), bdn); - else - retry = 1; - if (retry) - set_bit(R5_ReadError, &sh->dev[i].flags); - else { - clear_bit(R5_ReadError, &sh->dev[i].flags); - clear_bit(R5_ReWrite, &sh->dev[i].flags); - md_error(conf->mddev, rdev); - } - } - rdev_dec_pending(rdev, conf->mddev); - clear_bit(R5_LOCKED, &sh->dev[i].flags); - set_bit(STRIPE_HANDLE, &sh->state); - release_stripe(sh); -} - -static void raid5_end_write_request(struct bio *bi, int error) -{ - struct stripe_head *sh = bi->bi_private; - struct r5conf *conf = sh->raid_conf; - int disks = sh->disks, i; - struct md_rdev *uninitialized_var(rdev); - int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); - sector_t first_bad; - int bad_sectors; - int replacement = 0; - - for (i = 0 ; i < disks; i++) { - if (bi == &sh->dev[i].req) { - rdev = conf->disks[i].rdev; - break; - } - if (bi == &sh->dev[i].rreq) { - rdev = conf->disks[i].replacement; - if (rdev) - replacement = 1; - else - /* rdev was removed and 'replacement' - * replaced it. rdev is not removed - * until all requests are finished. - */ - rdev = conf->disks[i].rdev; - break; - } - } - pr_debug("end_write_request %llu/%d, count %d, uptodate: %d.\n", - (unsigned long long)sh->sector, i, atomic_read(&sh->count), - uptodate); - if (i == disks) { - BUG(); - return; - } - - if (replacement) { - if (!uptodate) - md_error(conf->mddev, rdev); - else if (is_badblock(rdev, sh->sector, - STRIPE_SECTORS, - &first_bad, &bad_sectors)) - set_bit(R5_MadeGoodRepl, &sh->dev[i].flags); - } else { - if (!uptodate) { - set_bit(WriteErrorSeen, &rdev->flags); - set_bit(R5_WriteError, &sh->dev[i].flags); - if (!test_and_set_bit(WantReplacement, &rdev->flags)) - set_bit(MD_RECOVERY_NEEDED, - &rdev->mddev->recovery); - } else if (is_badblock(rdev, sh->sector, - STRIPE_SECTORS, - &first_bad, &bad_sectors)) - set_bit(R5_MadeGood, &sh->dev[i].flags); - } - rdev_dec_pending(rdev, conf->mddev); - - if (!test_and_clear_bit(R5_DOUBLE_LOCKED, &sh->dev[i].flags)) - clear_bit(R5_LOCKED, &sh->dev[i].flags); - set_bit(STRIPE_HANDLE, &sh->state); - release_stripe(sh); -} - -static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous); - -static void raid5_build_block(struct stripe_head *sh, int i, int previous) -{ - struct r5dev *dev = &sh->dev[i]; - - bio_init(&dev->req); - dev->req.bi_io_vec = &dev->vec; - dev->req.bi_vcnt++; - dev->req.bi_max_vecs++; - dev->req.bi_private = sh; - dev->vec.bv_page = dev->page; - - bio_init(&dev->rreq); - dev->rreq.bi_io_vec = &dev->rvec; - dev->rreq.bi_vcnt++; - dev->rreq.bi_max_vecs++; - dev->rreq.bi_private = sh; - dev->rvec.bv_page = dev->page; - - dev->flags = 0; - dev->sector = compute_blocknr(sh, i, previous); -} - -static void error(struct mddev *mddev, struct md_rdev *rdev) -{ - char b[BDEVNAME_SIZE]; - struct r5conf *conf = mddev->private; - unsigned long flags; - pr_debug("raid456: error called\n"); - - spin_lock_irqsave(&conf->device_lock, flags); - clear_bit(In_sync, &rdev->flags); - mddev->degraded = calc_degraded(conf); - spin_unlock_irqrestore(&conf->device_lock, flags); - set_bit(MD_RECOVERY_INTR, &mddev->recovery); - - set_bit(Blocked, &rdev->flags); - set_bit(Faulty, &rdev->flags); - set_bit(MD_CHANGE_DEVS, &mddev->flags); - printk(KERN_ALERT - "md/raid:%s: Disk failure on %s, disabling device.\n" - "md/raid:%s: Operation continuing on %d devices.\n", - mdname(mddev), - bdevname(rdev->bdev, b), - mdname(mddev), - conf->raid_disks - mddev->degraded); -} - -/* - * Input: a 'big' sector number, - * Output: index of the data and parity disk, and the sector # in them. - */ -static sector_t raid5_compute_sector(struct r5conf *conf, sector_t r_sector, - int previous, int *dd_idx, - struct stripe_head *sh) -{ - sector_t stripe, stripe2; - sector_t chunk_number; - unsigned int chunk_offset; - int pd_idx, qd_idx; - int ddf_layout = 0; - sector_t new_sector; - int algorithm = previous ? conf->prev_algo - : conf->algorithm; - int sectors_per_chunk = previous ? conf->prev_chunk_sectors - : conf->chunk_sectors; - int raid_disks = previous ? conf->previous_raid_disks - : conf->raid_disks; - int data_disks = raid_disks - conf->max_degraded; - - /* First compute the information on this sector */ - - /* - * Compute the chunk number and the sector offset inside the chunk - */ - chunk_offset = sector_div(r_sector, sectors_per_chunk); - chunk_number = r_sector; - - /* - * Compute the stripe number - */ - stripe = chunk_number; - *dd_idx = sector_div(stripe, data_disks); - stripe2 = stripe; - /* - * Select the parity disk based on the user selected algorithm. - */ - pd_idx = qd_idx = -1; - switch(conf->level) { - case 4: - pd_idx = data_disks; - break; - case 5: - switch (algorithm) { - case ALGORITHM_LEFT_ASYMMETRIC: - pd_idx = data_disks - sector_div(stripe2, raid_disks); - if (*dd_idx >= pd_idx) - (*dd_idx)++; - break; - case ALGORITHM_RIGHT_ASYMMETRIC: - pd_idx = sector_div(stripe2, raid_disks); - if (*dd_idx >= pd_idx) - (*dd_idx)++; - break; - case ALGORITHM_LEFT_SYMMETRIC: - pd_idx = data_disks - sector_div(stripe2, raid_disks); - *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; - break; - case ALGORITHM_RIGHT_SYMMETRIC: - pd_idx = sector_div(stripe2, raid_disks); - *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; - break; - case ALGORITHM_PARITY_0: - pd_idx = 0; - (*dd_idx)++; - break; - case ALGORITHM_PARITY_N: - pd_idx = data_disks; - break; - default: - BUG(); - } - break; - case 6: - - switch (algorithm) { - case ALGORITHM_LEFT_ASYMMETRIC: - pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks); - qd_idx = pd_idx + 1; - if (pd_idx == raid_disks-1) { - (*dd_idx)++; /* Q D D D P */ - qd_idx = 0; - } else if (*dd_idx >= pd_idx) - (*dd_idx) += 2; /* D D P Q D */ - break; - case ALGORITHM_RIGHT_ASYMMETRIC: - pd_idx = sector_div(stripe2, raid_disks); - qd_idx = pd_idx + 1; - if (pd_idx == raid_disks-1) { - (*dd_idx)++; /* Q D D D P */ - qd_idx = 0; - } else if (*dd_idx >= pd_idx) - (*dd_idx) += 2; /* D D P Q D */ - break; - case ALGORITHM_LEFT_SYMMETRIC: - pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks); - qd_idx = (pd_idx + 1) % raid_disks; - *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks; - break; - case ALGORITHM_RIGHT_SYMMETRIC: - pd_idx = sector_div(stripe2, raid_disks); - qd_idx = (pd_idx + 1) % raid_disks; - *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks; - break; - - case ALGORITHM_PARITY_0: - pd_idx = 0; - qd_idx = 1; - (*dd_idx) += 2; - break; - case ALGORITHM_PARITY_N: - pd_idx = data_disks; - qd_idx = data_disks + 1; - break; - - case ALGORITHM_ROTATING_ZERO_RESTART: - /* Exactly the same as RIGHT_ASYMMETRIC, but or - * of blocks for computing Q is different. - */ - pd_idx = sector_div(stripe2, raid_disks); - qd_idx = pd_idx + 1; - if (pd_idx == raid_disks-1) { - (*dd_idx)++; /* Q D D D P */ - qd_idx = 0; - } else if (*dd_idx >= pd_idx) - (*dd_idx) += 2; /* D D P Q D */ - ddf_layout = 1; - break; - - case ALGORITHM_ROTATING_N_RESTART: - /* Same a left_asymmetric, by first stripe is - * D D D P Q rather than - * Q D D D P - */ - stripe2 += 1; - pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks); - qd_idx = pd_idx + 1; - if (pd_idx == raid_disks-1) { - (*dd_idx)++; /* Q D D D P */ - qd_idx = 0; - } else if (*dd_idx >= pd_idx) - (*dd_idx) += 2; /* D D P Q D */ - ddf_layout = 1; - break; - - case ALGORITHM_ROTATING_N_CONTINUE: - /* Same as left_symmetric but Q is before P */ - pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks); - qd_idx = (pd_idx + raid_disks - 1) % raid_disks; - *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; - ddf_layout = 1; - break; - - case ALGORITHM_LEFT_ASYMMETRIC_6: - /* RAID5 left_asymmetric, with Q on last device */ - pd_idx = data_disks - sector_div(stripe2, raid_disks-1); - if (*dd_idx >= pd_idx) - (*dd_idx)++; - qd_idx = raid_disks - 1; - break; - - case ALGORITHM_RIGHT_ASYMMETRIC_6: - pd_idx = sector_div(stripe2, raid_disks-1); - if (*dd_idx >= pd_idx) - (*dd_idx)++; - qd_idx = raid_disks - 1; - break; - - case ALGORITHM_LEFT_SYMMETRIC_6: - pd_idx = data_disks - sector_div(stripe2, raid_disks-1); - *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1); - qd_idx = raid_disks - 1; - break; - - case ALGORITHM_RIGHT_SYMMETRIC_6: - pd_idx = sector_div(stripe2, raid_disks-1); - *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1); - qd_idx = raid_disks - 1; - break; - - case ALGORITHM_PARITY_0_6: - pd_idx = 0; - (*dd_idx)++; - qd_idx = raid_disks - 1; - break; - - default: - BUG(); - } - break; - } - - if (sh) { - sh->pd_idx = pd_idx; - sh->qd_idx = qd_idx; - sh->ddf_layout = ddf_layout; - } - /* - * Finally, compute the new sector number - */ - new_sector = (sector_t)stripe * sectors_per_chunk + chunk_offset; - return new_sector; -} - - -static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous) -{ - struct r5conf *conf = sh->raid_conf; - int raid_disks = sh->disks; - int data_disks = raid_disks - conf->max_degraded; - sector_t new_sector = sh->sector, check; - int sectors_per_chunk = previous ? conf->prev_chunk_sectors - : conf->chunk_sectors; - int algorithm = previous ? conf->prev_algo - : conf->algorithm; - sector_t stripe; - int chunk_offset; - sector_t chunk_number; - int dummy1, dd_idx = i; - sector_t r_sector; - struct stripe_head sh2; - - - chunk_offset = sector_div(new_sector, sectors_per_chunk); - stripe = new_sector; - - if (i == sh->pd_idx) - return 0; - switch(conf->level) { - case 4: break; - case 5: - switch (algorithm) { - case ALGORITHM_LEFT_ASYMMETRIC: - case ALGORITHM_RIGHT_ASYMMETRIC: - if (i > sh->pd_idx) - i--; - break; - case ALGORITHM_LEFT_SYMMETRIC: - case ALGORITHM_RIGHT_SYMMETRIC: - if (i < sh->pd_idx) - i += raid_disks; - i -= (sh->pd_idx + 1); - break; - case ALGORITHM_PARITY_0: - i -= 1; - break; - case ALGORITHM_PARITY_N: - break; - default: - BUG(); - } - break; - case 6: - if (i == sh->qd_idx) - return 0; /* It is the Q disk */ - switch (algorithm) { - case ALGORITHM_LEFT_ASYMMETRIC: - case ALGORITHM_RIGHT_ASYMMETRIC: - case ALGORITHM_ROTATING_ZERO_RESTART: - case ALGORITHM_ROTATING_N_RESTART: - if (sh->pd_idx == raid_disks-1) - i--; /* Q D D D P */ - else if (i > sh->pd_idx) - i -= 2; /* D D P Q D */ - break; - case ALGORITHM_LEFT_SYMMETRIC: - case ALGORITHM_RIGHT_SYMMETRIC: - if (sh->pd_idx == raid_disks-1) - i--; /* Q D D D P */ - else { - /* D D P Q D */ - if (i < sh->pd_idx) - i += raid_disks; - i -= (sh->pd_idx + 2); - } - break; - case ALGORITHM_PARITY_0: - i -= 2; - break; - case ALGORITHM_PARITY_N: - break; - case ALGORITHM_ROTATING_N_CONTINUE: - /* Like left_symmetric, but P is before Q */ - if (sh->pd_idx == 0) - i--; /* P D D D Q */ - else { - /* D D Q P D */ - if (i < sh->pd_idx) - i += raid_disks; - i -= (sh->pd_idx + 1); - } - break; - case ALGORITHM_LEFT_ASYMMETRIC_6: - case ALGORITHM_RIGHT_ASYMMETRIC_6: - if (i > sh->pd_idx) - i--; - break; - case ALGORITHM_LEFT_SYMMETRIC_6: - case ALGORITHM_RIGHT_SYMMETRIC_6: - if (i < sh->pd_idx) - i += data_disks + 1; - i -= (sh->pd_idx + 1); - break; - case ALGORITHM_PARITY_0_6: - i -= 1; - break; - default: - BUG(); - } - break; - } - - chunk_number = stripe * data_disks + i; - r_sector = chunk_number * sectors_per_chunk + chunk_offset; - - check = raid5_compute_sector(conf, r_sector, - previous, &dummy1, &sh2); - if (check != sh->sector || dummy1 != dd_idx || sh2.pd_idx != sh->pd_idx - || sh2.qd_idx != sh->qd_idx) { - printk(KERN_ERR "md/raid:%s: compute_blocknr: map not correct\n", - mdname(conf->mddev)); - return 0; - } - return r_sector; -} - - -static void -schedule_reconstruction(struct stripe_head *sh, struct stripe_head_state *s, - int rcw, int expand) -{ - int i, pd_idx = sh->pd_idx, disks = sh->disks; - struct r5conf *conf = sh->raid_conf; - int level = conf->level; - - if (rcw) { - /* if we are not expanding this is a proper write request, and - * there will be bios with new data to be drained into the - * stripe cache - */ - if (!expand) { - sh->reconstruct_state = reconstruct_state_drain_run; - set_bit(STRIPE_OP_BIODRAIN, &s->ops_request); - } else - sh->reconstruct_state = reconstruct_state_run; - - set_bit(STRIPE_OP_RECONSTRUCT, &s->ops_request); - - for (i = disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - - if (dev->towrite) { - set_bit(R5_LOCKED, &dev->flags); - set_bit(R5_Wantdrain, &dev->flags); - if (!expand) - clear_bit(R5_UPTODATE, &dev->flags); - s->locked++; - } - } - if (s->locked + conf->max_degraded == disks) - if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state)) - atomic_inc(&conf->pending_full_writes); - } else { - BUG_ON(level == 6); - BUG_ON(!(test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags) || - test_bit(R5_Wantcompute, &sh->dev[pd_idx].flags))); - - sh->reconstruct_state = reconstruct_state_prexor_drain_run; - set_bit(STRIPE_OP_PREXOR, &s->ops_request); - set_bit(STRIPE_OP_BIODRAIN, &s->ops_request); - set_bit(STRIPE_OP_RECONSTRUCT, &s->ops_request); - - for (i = disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - if (i == pd_idx) - continue; - - if (dev->towrite && - (test_bit(R5_UPTODATE, &dev->flags) || - test_bit(R5_Wantcompute, &dev->flags))) { - set_bit(R5_Wantdrain, &dev->flags); - set_bit(R5_LOCKED, &dev->flags); - clear_bit(R5_UPTODATE, &dev->flags); - s->locked++; - } - } - } - - /* keep the parity disk(s) locked while asynchronous operations - * are in flight - */ - set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); - clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); - s->locked++; - - if (level == 6) { - int qd_idx = sh->qd_idx; - struct r5dev *dev = &sh->dev[qd_idx]; - - set_bit(R5_LOCKED, &dev->flags); - clear_bit(R5_UPTODATE, &dev->flags); - s->locked++; - } - - pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n", - __func__, (unsigned long long)sh->sector, - s->locked, s->ops_request); -} - -/* - * Each stripe/dev can have one or more bion attached. - * toread/towrite point to the first in a chain. - * The bi_next chain must be in order. - */ -static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx, int forwrite) -{ - struct bio **bip; - struct r5conf *conf = sh->raid_conf; - int firstwrite=0; - - pr_debug("adding bi b#%llu to stripe s#%llu\n", - (unsigned long long)bi->bi_sector, - (unsigned long long)sh->sector); - - - spin_lock_irq(&conf->device_lock); - if (forwrite) { - bip = &sh->dev[dd_idx].towrite; - if (*bip == NULL && sh->dev[dd_idx].written == NULL) - firstwrite = 1; - } else - bip = &sh->dev[dd_idx].toread; - while (*bip && (*bip)->bi_sector < bi->bi_sector) { - if ((*bip)->bi_sector + ((*bip)->bi_size >> 9) > bi->bi_sector) - goto overlap; - bip = & (*bip)->bi_next; - } - if (*bip && (*bip)->bi_sector < bi->bi_sector + ((bi->bi_size)>>9)) - goto overlap; - - BUG_ON(*bip && bi->bi_next && (*bip) != bi->bi_next); - if (*bip) - bi->bi_next = *bip; - *bip = bi; - bi->bi_phys_segments++; - - if (forwrite) { - /* check if page is covered */ - sector_t sector = sh->dev[dd_idx].sector; - for (bi=sh->dev[dd_idx].towrite; - sector < sh->dev[dd_idx].sector + STRIPE_SECTORS && - bi && bi->bi_sector <= sector; - bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) { - if (bi->bi_sector + (bi->bi_size>>9) >= sector) - sector = bi->bi_sector + (bi->bi_size>>9); - } - if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS) - set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags); - } - spin_unlock_irq(&conf->device_lock); - - pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n", - (unsigned long long)(*bip)->bi_sector, - (unsigned long long)sh->sector, dd_idx); - - if (conf->mddev->bitmap && firstwrite) { - bitmap_startwrite(conf->mddev->bitmap, sh->sector, - STRIPE_SECTORS, 0); - sh->bm_seq = conf->seq_flush+1; - set_bit(STRIPE_BIT_DELAY, &sh->state); - } - return 1; - - overlap: - set_bit(R5_Overlap, &sh->dev[dd_idx].flags); - spin_unlock_irq(&conf->device_lock); - return 0; -} - -static void end_reshape(struct r5conf *conf); - -static void stripe_set_idx(sector_t stripe, struct r5conf *conf, int previous, - struct stripe_head *sh) -{ - int sectors_per_chunk = - previous ? conf->prev_chunk_sectors : conf->chunk_sectors; - int dd_idx; - int chunk_offset = sector_div(stripe, sectors_per_chunk); - int disks = previous ? conf->previous_raid_disks : conf->raid_disks; - - raid5_compute_sector(conf, - stripe * (disks - conf->max_degraded) - *sectors_per_chunk + chunk_offset, - previous, - &dd_idx, sh); -} - -static void -handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh, - struct stripe_head_state *s, int disks, - struct bio **return_bi) -{ - int i; - for (i = disks; i--; ) { - struct bio *bi; - int bitmap_end = 0; - - if (test_bit(R5_ReadError, &sh->dev[i].flags)) { - struct md_rdev *rdev; - rcu_read_lock(); - rdev = rcu_dereference(conf->disks[i].rdev); - if (rdev && test_bit(In_sync, &rdev->flags)) - atomic_inc(&rdev->nr_pending); - else - rdev = NULL; - rcu_read_unlock(); - if (rdev) { - if (!rdev_set_badblocks( - rdev, - sh->sector, - STRIPE_SECTORS, 0)) - md_error(conf->mddev, rdev); - rdev_dec_pending(rdev, conf->mddev); - } - } - spin_lock_irq(&conf->device_lock); - /* fail all writes first */ - bi = sh->dev[i].towrite; - sh->dev[i].towrite = NULL; - if (bi) { - s->to_write--; - bitmap_end = 1; - } - - if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) - wake_up(&conf->wait_for_overlap); - - while (bi && bi->bi_sector < - sh->dev[i].sector + STRIPE_SECTORS) { - struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); - clear_bit(BIO_UPTODATE, &bi->bi_flags); - if (!raid5_dec_bi_phys_segments(bi)) { - md_write_end(conf->mddev); - bi->bi_next = *return_bi; - *return_bi = bi; - } - bi = nextbi; - } - /* and fail all 'written' */ - bi = sh->dev[i].written; - sh->dev[i].written = NULL; - if (bi) bitmap_end = 1; - while (bi && bi->bi_sector < - sh->dev[i].sector + STRIPE_SECTORS) { - struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector); - clear_bit(BIO_UPTODATE, &bi->bi_flags); - if (!raid5_dec_bi_phys_segments(bi)) { - md_write_end(conf->mddev); - bi->bi_next = *return_bi; - *return_bi = bi; - } - bi = bi2; - } - - /* fail any reads if this device is non-operational and - * the data has not reached the cache yet. - */ - if (!test_bit(R5_Wantfill, &sh->dev[i].flags) && - (!test_bit(R5_Insync, &sh->dev[i].flags) || - test_bit(R5_ReadError, &sh->dev[i].flags))) { - bi = sh->dev[i].toread; - sh->dev[i].toread = NULL; - if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) - wake_up(&conf->wait_for_overlap); - if (bi) s->to_read--; - while (bi && bi->bi_sector < - sh->dev[i].sector + STRIPE_SECTORS) { - struct bio *nextbi = - r5_next_bio(bi, sh->dev[i].sector); - clear_bit(BIO_UPTODATE, &bi->bi_flags); - if (!raid5_dec_bi_phys_segments(bi)) { - bi->bi_next = *return_bi; - *return_bi = bi; - } - bi = nextbi; - } - } - spin_unlock_irq(&conf->device_lock); - if (bitmap_end) - bitmap_endwrite(conf->mddev->bitmap, sh->sector, - STRIPE_SECTORS, 0, 0); - /* If we were in the middle of a write the parity block might - * still be locked - so just clear all R5_LOCKED flags - */ - clear_bit(R5_LOCKED, &sh->dev[i].flags); - } - - if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) - if (atomic_dec_and_test(&conf->pending_full_writes)) - md_wakeup_thread(conf->mddev->thread); -} - -static void -handle_failed_sync(struct r5conf *conf, struct stripe_head *sh, - struct stripe_head_state *s) -{ - int abort = 0; - int i; - - clear_bit(STRIPE_SYNCING, &sh->state); - s->syncing = 0; - s->replacing = 0; - /* There is nothing more to do for sync/check/repair. - * Don't even need to abort as that is handled elsewhere - * if needed, and not always wanted e.g. if there is a known - * bad block here. - * For recover/replace we need to record a bad block on all - * non-sync devices, or abort the recovery - */ - if (test_bit(MD_RECOVERY_RECOVER, &conf->mddev->recovery)) { - /* During recovery devices cannot be removed, so - * locking and refcounting of rdevs is not needed - */ - for (i = 0; i < conf->raid_disks; i++) { - struct md_rdev *rdev = conf->disks[i].rdev; - if (rdev - && !test_bit(Faulty, &rdev->flags) - && !test_bit(In_sync, &rdev->flags) - && !rdev_set_badblocks(rdev, sh->sector, - STRIPE_SECTORS, 0)) - abort = 1; - rdev = conf->disks[i].replacement; - if (rdev - && !test_bit(Faulty, &rdev->flags) - && !test_bit(In_sync, &rdev->flags) - && !rdev_set_badblocks(rdev, sh->sector, - STRIPE_SECTORS, 0)) - abort = 1; - } - if (abort) - conf->recovery_disabled = - conf->mddev->recovery_disabled; - } - md_done_sync(conf->mddev, STRIPE_SECTORS, !abort); -} - -static int want_replace(struct stripe_head *sh, int disk_idx) -{ - struct md_rdev *rdev; - int rv = 0; - /* Doing recovery so rcu locking not required */ - rdev = sh->raid_conf->disks[disk_idx].replacement; - if (rdev - && !test_bit(Faulty, &rdev->flags) - && !test_bit(In_sync, &rdev->flags) - && (rdev->recovery_offset <= sh->sector - || rdev->mddev->recovery_cp <= sh->sector)) - rv = 1; - - return rv; -} - -/* fetch_block - checks the given member device to see if its data needs - * to be read or computed to satisfy a request. - * - * Returns 1 when no more member devices need to be checked, otherwise returns - * 0 to tell the loop in handle_stripe_fill to continue - */ -static int fetch_block(struct stripe_head *sh, struct stripe_head_state *s, - int disk_idx, int disks) -{ - struct r5dev *dev = &sh->dev[disk_idx]; - struct r5dev *fdev[2] = { &sh->dev[s->failed_num[0]], - &sh->dev[s->failed_num[1]] }; - - /* is the data in this block needed, and can we get it? */ - if (!test_bit(R5_LOCKED, &dev->flags) && - !test_bit(R5_UPTODATE, &dev->flags) && - (dev->toread || - (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) || - s->syncing || s->expanding || - (s->replacing && want_replace(sh, disk_idx)) || - (s->failed >= 1 && fdev[0]->toread) || - (s->failed >= 2 && fdev[1]->toread) || - (sh->raid_conf->level <= 5 && s->failed && fdev[0]->towrite && - !test_bit(R5_OVERWRITE, &fdev[0]->flags)) || - (sh->raid_conf->level == 6 && s->failed && s->to_write))) { - /* we would like to get this block, possibly by computing it, - * otherwise read it if the backing disk is insync - */ - BUG_ON(test_bit(R5_Wantcompute, &dev->flags)); - BUG_ON(test_bit(R5_Wantread, &dev->flags)); - if ((s->uptodate == disks - 1) && - (s->failed && (disk_idx == s->failed_num[0] || - disk_idx == s->failed_num[1]))) { - /* have disk failed, and we're requested to fetch it; - * do compute it - */ - pr_debug("Computing stripe %llu block %d\n", - (unsigned long long)sh->sector, disk_idx); - set_bit(STRIPE_COMPUTE_RUN, &sh->state); - set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); - set_bit(R5_Wantcompute, &dev->flags); - sh->ops.target = disk_idx; - sh->ops.target2 = -1; /* no 2nd target */ - s->req_compute = 1; - /* Careful: from this point on 'uptodate' is in the eye - * of raid_run_ops which services 'compute' operations - * before writes. R5_Wantcompute flags a block that will - * be R5_UPTODATE by the time it is needed for a - * subsequent operation. - */ - s->uptodate++; - return 1; - } else if (s->uptodate == disks-2 && s->failed >= 2) { - /* Computing 2-failure is *very* expensive; only - * do it if failed >= 2 - */ - int other; - for (other = disks; other--; ) { - if (other == disk_idx) - continue; - if (!test_bit(R5_UPTODATE, - &sh->dev[other].flags)) - break; - } - BUG_ON(other < 0); - pr_debug("Computing stripe %llu blocks %d,%d\n", - (unsigned long long)sh->sector, - disk_idx, other); - set_bit(STRIPE_COMPUTE_RUN, &sh->state); - set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); - set_bit(R5_Wantcompute, &sh->dev[disk_idx].flags); - set_bit(R5_Wantcompute, &sh->dev[other].flags); - sh->ops.target = disk_idx; - sh->ops.target2 = other; - s->uptodate += 2; - s->req_compute = 1; - return 1; - } else if (test_bit(R5_Insync, &dev->flags)) { - set_bit(R5_LOCKED, &dev->flags); - set_bit(R5_Wantread, &dev->flags); - s->locked++; - pr_debug("Reading block %d (sync=%d)\n", - disk_idx, s->syncing); - } - } - - return 0; -} - -/** - * handle_stripe_fill - read or compute data to satisfy pending requests. - */ -static void handle_stripe_fill(struct stripe_head *sh, - struct stripe_head_state *s, - int disks) -{ - int i; - - /* look for blocks to read/compute, skip this if a compute - * is already in flight, or if the stripe contents are in the - * midst of changing due to a write - */ - if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state && - !sh->reconstruct_state) - for (i = disks; i--; ) - if (fetch_block(sh, s, i, disks)) - break; - set_bit(STRIPE_HANDLE, &sh->state); -} - - -/* handle_stripe_clean_event - * any written block on an uptodate or failed drive can be returned. - * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but - * never LOCKED, so we don't need to test 'failed' directly. - */ -static void handle_stripe_clean_event(struct r5conf *conf, - struct stripe_head *sh, int disks, struct bio **return_bi) -{ - int i; - struct r5dev *dev; - - for (i = disks; i--; ) - if (sh->dev[i].written) { - dev = &sh->dev[i]; - if (!test_bit(R5_LOCKED, &dev->flags) && - test_bit(R5_UPTODATE, &dev->flags)) { - /* We can return any write requests */ - struct bio *wbi, *wbi2; - int bitmap_end = 0; - pr_debug("Return write for disc %d\n", i); - spin_lock_irq(&conf->device_lock); - wbi = dev->written; - dev->written = NULL; - while (wbi && wbi->bi_sector < - dev->sector + STRIPE_SECTORS) { - wbi2 = r5_next_bio(wbi, dev->sector); - if (!raid5_dec_bi_phys_segments(wbi)) { - md_write_end(conf->mddev); - wbi->bi_next = *return_bi; - *return_bi = wbi; - } - wbi = wbi2; - } - if (dev->towrite == NULL) - bitmap_end = 1; - spin_unlock_irq(&conf->device_lock); - if (bitmap_end) - bitmap_endwrite(conf->mddev->bitmap, - sh->sector, - STRIPE_SECTORS, - !test_bit(STRIPE_DEGRADED, &sh->state), - 0); - } - } - - if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) - if (atomic_dec_and_test(&conf->pending_full_writes)) - md_wakeup_thread(conf->mddev->thread); -} - -static void handle_stripe_dirtying(struct r5conf *conf, - struct stripe_head *sh, - struct stripe_head_state *s, - int disks) -{ - int rmw = 0, rcw = 0, i; - if (conf->max_degraded == 2) { - /* RAID6 requires 'rcw' in current implementation - * Calculate the real rcw later - for now fake it - * look like rcw is cheaper - */ - rcw = 1; rmw = 2; - } else for (i = disks; i--; ) { - /* would I have to read this buffer for read_modify_write */ - struct r5dev *dev = &sh->dev[i]; - if ((dev->towrite || i == sh->pd_idx) && - !test_bit(R5_LOCKED, &dev->flags) && - !(test_bit(R5_UPTODATE, &dev->flags) || - test_bit(R5_Wantcompute, &dev->flags))) { - if (test_bit(R5_Insync, &dev->flags)) - rmw++; - else - rmw += 2*disks; /* cannot read it */ - } - /* Would I have to read this buffer for reconstruct_write */ - if (!test_bit(R5_OVERWRITE, &dev->flags) && i != sh->pd_idx && - !test_bit(R5_LOCKED, &dev->flags) && - !(test_bit(R5_UPTODATE, &dev->flags) || - test_bit(R5_Wantcompute, &dev->flags))) { - if (test_bit(R5_Insync, &dev->flags)) rcw++; - else - rcw += 2*disks; - } - } - pr_debug("for sector %llu, rmw=%d rcw=%d\n", - (unsigned long long)sh->sector, rmw, rcw); - set_bit(STRIPE_HANDLE, &sh->state); - if (rmw < rcw && rmw > 0) - /* prefer read-modify-write, but need to get some data */ - for (i = disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - if ((dev->towrite || i == sh->pd_idx) && - !test_bit(R5_LOCKED, &dev->flags) && - !(test_bit(R5_UPTODATE, &dev->flags) || - test_bit(R5_Wantcompute, &dev->flags)) && - test_bit(R5_Insync, &dev->flags)) { - if ( - test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { - pr_debug("Read_old block " - "%d for r-m-w\n", i); - set_bit(R5_LOCKED, &dev->flags); - set_bit(R5_Wantread, &dev->flags); - s->locked++; - } else { - set_bit(STRIPE_DELAYED, &sh->state); - set_bit(STRIPE_HANDLE, &sh->state); - } - } - } - if (rcw <= rmw && rcw > 0) { - /* want reconstruct write, but need to get some data */ - rcw = 0; - for (i = disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - if (!test_bit(R5_OVERWRITE, &dev->flags) && - i != sh->pd_idx && i != sh->qd_idx && - !test_bit(R5_LOCKED, &dev->flags) && - !(test_bit(R5_UPTODATE, &dev->flags) || - test_bit(R5_Wantcompute, &dev->flags))) { - rcw++; - if (!test_bit(R5_Insync, &dev->flags)) - continue; /* it's a failed drive */ - if ( - test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { - pr_debug("Read_old block " - "%d for Reconstruct\n", i); - set_bit(R5_LOCKED, &dev->flags); - set_bit(R5_Wantread, &dev->flags); - s->locked++; - } else { - set_bit(STRIPE_DELAYED, &sh->state); - set_bit(STRIPE_HANDLE, &sh->state); - } - } - } - } - /* now if nothing is locked, and if we have enough data, - * we can start a write request - */ - /* since handle_stripe can be called at any time we need to handle the - * case where a compute block operation has been submitted and then a - * subsequent call wants to start a write request. raid_run_ops only - * handles the case where compute block and reconstruct are requested - * simultaneously. If this is not the case then new writes need to be - * held off until the compute completes. - */ - if ((s->req_compute || !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) && - (s->locked == 0 && (rcw == 0 || rmw == 0) && - !test_bit(STRIPE_BIT_DELAY, &sh->state))) - schedule_reconstruction(sh, s, rcw == 0, 0); -} - -static void handle_parity_checks5(struct r5conf *conf, struct stripe_head *sh, - struct stripe_head_state *s, int disks) -{ - struct r5dev *dev = NULL; - - set_bit(STRIPE_HANDLE, &sh->state); - - switch (sh->check_state) { - case check_state_idle: - /* start a new check operation if there are no failures */ - if (s->failed == 0) { - BUG_ON(s->uptodate != disks); - sh->check_state = check_state_run; - set_bit(STRIPE_OP_CHECK, &s->ops_request); - clear_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags); - s->uptodate--; - break; - } - dev = &sh->dev[s->failed_num[0]]; - /* fall through */ - case check_state_compute_result: - sh->check_state = check_state_idle; - if (!dev) - dev = &sh->dev[sh->pd_idx]; - - /* check that a write has not made the stripe insync */ - if (test_bit(STRIPE_INSYNC, &sh->state)) - break; - - /* either failed parity check, or recovery is happening */ - BUG_ON(!test_bit(R5_UPTODATE, &dev->flags)); - BUG_ON(s->uptodate != disks); - - set_bit(R5_LOCKED, &dev->flags); - s->locked++; - set_bit(R5_Wantwrite, &dev->flags); - - clear_bit(STRIPE_DEGRADED, &sh->state); - set_bit(STRIPE_INSYNC, &sh->state); - break; - case check_state_run: - break; /* we will be called again upon completion */ - case check_state_check_result: - sh->check_state = check_state_idle; - - /* if a failure occurred during the check operation, leave - * STRIPE_INSYNC not set and let the stripe be handled again - */ - if (s->failed) - break; - - /* handle a successful check operation, if parity is correct - * we are done. Otherwise update the mismatch count and repair - * parity if !MD_RECOVERY_CHECK - */ - if ((sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) == 0) - /* parity is correct (on disc, - * not in buffer any more) - */ - set_bit(STRIPE_INSYNC, &sh->state); - else { - conf->mddev->resync_mismatches += STRIPE_SECTORS; - if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) - /* don't try to repair!! */ - set_bit(STRIPE_INSYNC, &sh->state); - else { - sh->check_state = check_state_compute_run; - set_bit(STRIPE_COMPUTE_RUN, &sh->state); - set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); - set_bit(R5_Wantcompute, - &sh->dev[sh->pd_idx].flags); - sh->ops.target = sh->pd_idx; - sh->ops.target2 = -1; - s->uptodate++; - } - } - break; - case check_state_compute_run: - break; - default: - printk(KERN_ERR "%s: unknown check_state: %d sector: %llu\n", - __func__, sh->check_state, - (unsigned long long) sh->sector); - BUG(); - } -} - - -static void handle_parity_checks6(struct r5conf *conf, struct stripe_head *sh, - struct stripe_head_state *s, - int disks) -{ - int pd_idx = sh->pd_idx; - int qd_idx = sh->qd_idx; - struct r5dev *dev; - - set_bit(STRIPE_HANDLE, &sh->state); - - BUG_ON(s->failed > 2); - - /* Want to check and possibly repair P and Q. - * However there could be one 'failed' device, in which - * case we can only check one of them, possibly using the - * other to generate missing data - */ - - switch (sh->check_state) { - case check_state_idle: - /* start a new check operation if there are < 2 failures */ - if (s->failed == s->q_failed) { - /* The only possible failed device holds Q, so it - * makes sense to check P (If anything else were failed, - * we would have used P to recreate it). - */ - sh->check_state = check_state_run; - } - if (!s->q_failed && s->failed < 2) { - /* Q is not failed, and we didn't use it to generate - * anything, so it makes sense to check it - */ - if (sh->check_state == check_state_run) - sh->check_state = check_state_run_pq; - else - sh->check_state = check_state_run_q; - } - - /* discard potentially stale zero_sum_result */ - sh->ops.zero_sum_result = 0; - - if (sh->check_state == check_state_run) { - /* async_xor_zero_sum destroys the contents of P */ - clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); - s->uptodate--; - } - if (sh->check_state >= check_state_run && - sh->check_state <= check_state_run_pq) { - /* async_syndrome_zero_sum preserves P and Q, so - * no need to mark them !uptodate here - */ - set_bit(STRIPE_OP_CHECK, &s->ops_request); - break; - } - - /* we have 2-disk failure */ - BUG_ON(s->failed != 2); - /* fall through */ - case check_state_compute_result: - sh->check_state = check_state_idle; - - /* check that a write has not made the stripe insync */ - if (test_bit(STRIPE_INSYNC, &sh->state)) - break; - - /* now write out any block on a failed drive, - * or P or Q if they were recomputed - */ - BUG_ON(s->uptodate < disks - 1); /* We don't need Q to recover */ - if (s->failed == 2) { - dev = &sh->dev[s->failed_num[1]]; - s->locked++; - set_bit(R5_LOCKED, &dev->flags); - set_bit(R5_Wantwrite, &dev->flags); - } - if (s->failed >= 1) { - dev = &sh->dev[s->failed_num[0]]; - s->locked++; - set_bit(R5_LOCKED, &dev->flags); - set_bit(R5_Wantwrite, &dev->flags); - } - if (sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) { - dev = &sh->dev[pd_idx]; - s->locked++; - set_bit(R5_LOCKED, &dev->flags); - set_bit(R5_Wantwrite, &dev->flags); - } - if (sh->ops.zero_sum_result & SUM_CHECK_Q_RESULT) { - dev = &sh->dev[qd_idx]; - s->locked++; - set_bit(R5_LOCKED, &dev->flags); - set_bit(R5_Wantwrite, &dev->flags); - } - clear_bit(STRIPE_DEGRADED, &sh->state); - - set_bit(STRIPE_INSYNC, &sh->state); - break; - case check_state_run: - case check_state_run_q: - case check_state_run_pq: - break; /* we will be called again upon completion */ - case check_state_check_result: - sh->check_state = check_state_idle; - - /* handle a successful check operation, if parity is correct - * we are done. Otherwise update the mismatch count and repair - * parity if !MD_RECOVERY_CHECK - */ - if (sh->ops.zero_sum_result == 0) { - /* both parities are correct */ - if (!s->failed) - set_bit(STRIPE_INSYNC, &sh->state); - else { - /* in contrast to the raid5 case we can validate - * parity, but still have a failure to write - * back - */ - sh->check_state = check_state_compute_result; - /* Returning at this point means that we may go - * off and bring p and/or q uptodate again so - * we make sure to check zero_sum_result again - * to verify if p or q need writeback - */ - } - } else { - conf->mddev->resync_mismatches += STRIPE_SECTORS; - if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) - /* don't try to repair!! */ - set_bit(STRIPE_INSYNC, &sh->state); - else { - int *target = &sh->ops.target; - - sh->ops.target = -1; - sh->ops.target2 = -1; - sh->check_state = check_state_compute_run; - set_bit(STRIPE_COMPUTE_RUN, &sh->state); - set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); - if (sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) { - set_bit(R5_Wantcompute, - &sh->dev[pd_idx].flags); - *target = pd_idx; - target = &sh->ops.target2; - s->uptodate++; - } - if (sh->ops.zero_sum_result & SUM_CHECK_Q_RESULT) { - set_bit(R5_Wantcompute, - &sh->dev[qd_idx].flags); - *target = qd_idx; - s->uptodate++; - } - } - } - break; - case check_state_compute_run: - break; - default: - printk(KERN_ERR "%s: unknown check_state: %d sector: %llu\n", - __func__, sh->check_state, - (unsigned long long) sh->sector); - BUG(); - } -} - -static void handle_stripe_expansion(struct r5conf *conf, struct stripe_head *sh) -{ - int i; - - /* We have read all the blocks in this stripe and now we need to - * copy some of them into a target stripe for expand. - */ - struct dma_async_tx_descriptor *tx = NULL; - clear_bit(STRIPE_EXPAND_SOURCE, &sh->state); - for (i = 0; i < sh->disks; i++) - if (i != sh->pd_idx && i != sh->qd_idx) { - int dd_idx, j; - struct stripe_head *sh2; - struct async_submit_ctl submit; - - sector_t bn = compute_blocknr(sh, i, 1); - sector_t s = raid5_compute_sector(conf, bn, 0, - &dd_idx, NULL); - sh2 = get_active_stripe(conf, s, 0, 1, 1); - if (sh2 == NULL) - /* so far only the early blocks of this stripe - * have been requested. When later blocks - * get requested, we will try again - */ - continue; - if (!test_bit(STRIPE_EXPANDING, &sh2->state) || - test_bit(R5_Expanded, &sh2->dev[dd_idx].flags)) { - /* must have already done this block */ - release_stripe(sh2); - continue; - } - - /* place all the copies on one channel */ - init_async_submit(&submit, 0, tx, NULL, NULL, NULL); - tx = async_memcpy(sh2->dev[dd_idx].page, - sh->dev[i].page, 0, 0, STRIPE_SIZE, - &submit); - - set_bit(R5_Expanded, &sh2->dev[dd_idx].flags); - set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags); - for (j = 0; j < conf->raid_disks; j++) - if (j != sh2->pd_idx && - j != sh2->qd_idx && - !test_bit(R5_Expanded, &sh2->dev[j].flags)) - break; - if (j == conf->raid_disks) { - set_bit(STRIPE_EXPAND_READY, &sh2->state); - set_bit(STRIPE_HANDLE, &sh2->state); - } - release_stripe(sh2); - - } - /* done submitting copies, wait for them to complete */ - if (tx) { - async_tx_ack(tx); - dma_wait_for_async_tx(tx); - } -} - -/* - * handle_stripe - do things to a stripe. - * - * We lock the stripe by setting STRIPE_ACTIVE and then examine the - * state of various bits to see what needs to be done. - * Possible results: - * return some read requests which now have data - * return some write requests which are safely on storage - * schedule a read on some buffers - * schedule a write of some buffers - * return confirmation of parity correctness - * - */ - -static void analyse_stripe(struct stripe_head *sh, struct stripe_head_state *s) -{ - struct r5conf *conf = sh->raid_conf; - int disks = sh->disks; - struct r5dev *dev; - int i; - int do_recovery = 0; - - memset(s, 0, sizeof(*s)); - - s->expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); - s->expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); - s->failed_num[0] = -1; - s->failed_num[1] = -1; - - /* Now to look around and see what can be done */ - rcu_read_lock(); - spin_lock_irq(&conf->device_lock); - for (i=disks; i--; ) { - struct md_rdev *rdev; - sector_t first_bad; - int bad_sectors; - int is_bad = 0; - - dev = &sh->dev[i]; - - pr_debug("check %d: state 0x%lx read %p write %p written %p\n", - i, dev->flags, - dev->toread, dev->towrite, dev->written); - /* maybe we can reply to a read - * - * new wantfill requests are only permitted while - * ops_complete_biofill is guaranteed to be inactive - */ - if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread && - !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) - set_bit(R5_Wantfill, &dev->flags); - - /* now count some things */ - if (test_bit(R5_LOCKED, &dev->flags)) - s->locked++; - if (test_bit(R5_UPTODATE, &dev->flags)) - s->uptodate++; - if (test_bit(R5_Wantcompute, &dev->flags)) { - s->compute++; - BUG_ON(s->compute > 2); - } - - if (test_bit(R5_Wantfill, &dev->flags)) - s->to_fill++; - else if (dev->toread) - s->to_read++; - if (dev->towrite) { - s->to_write++; - if (!test_bit(R5_OVERWRITE, &dev->flags)) - s->non_overwrite++; - } - if (dev->written) - s->written++; - /* Prefer to use the replacement for reads, but only - * if it is recovered enough and has no bad blocks. - */ - rdev = rcu_dereference(conf->disks[i].replacement); - if (rdev && !test_bit(Faulty, &rdev->flags) && - rdev->recovery_offset >= sh->sector + STRIPE_SECTORS && - !is_badblock(rdev, sh->sector, STRIPE_SECTORS, - &first_bad, &bad_sectors)) - set_bit(R5_ReadRepl, &dev->flags); - else { - if (rdev) - set_bit(R5_NeedReplace, &dev->flags); - rdev = rcu_dereference(conf->disks[i].rdev); - clear_bit(R5_ReadRepl, &dev->flags); - } - if (rdev && test_bit(Faulty, &rdev->flags)) - rdev = NULL; - if (rdev) { - is_bad = is_badblock(rdev, sh->sector, STRIPE_SECTORS, - &first_bad, &bad_sectors); - if (s->blocked_rdev == NULL - && (test_bit(Blocked, &rdev->flags) - || is_bad < 0)) { - if (is_bad < 0) - set_bit(BlockedBadBlocks, - &rdev->flags); - s->blocked_rdev = rdev; - atomic_inc(&rdev->nr_pending); - } - } - clear_bit(R5_Insync, &dev->flags); - if (!rdev) - /* Not in-sync */; - else if (is_bad) { - /* also not in-sync */ - if (!test_bit(WriteErrorSeen, &rdev->flags) && - test_bit(R5_UPTODATE, &dev->flags)) { - /* treat as in-sync, but with a read error - * which we can now try to correct - */ - set_bit(R5_Insync, &dev->flags); - set_bit(R5_ReadError, &dev->flags); - } - } else if (test_bit(In_sync, &rdev->flags)) - set_bit(R5_Insync, &dev->flags); - else if (sh->sector + STRIPE_SECTORS <= rdev->recovery_offset) - /* in sync if before recovery_offset */ - set_bit(R5_Insync, &dev->flags); - else if (test_bit(R5_UPTODATE, &dev->flags) && - test_bit(R5_Expanded, &dev->flags)) - /* If we've reshaped into here, we assume it is Insync. - * We will shortly update recovery_offset to make - * it official. - */ - set_bit(R5_Insync, &dev->flags); - - if (rdev && test_bit(R5_WriteError, &dev->flags)) { - /* This flag does not apply to '.replacement' - * only to .rdev, so make sure to check that*/ - struct md_rdev *rdev2 = rcu_dereference( - conf->disks[i].rdev); - if (rdev2 == rdev) - clear_bit(R5_Insync, &dev->flags); - if (rdev2 && !test_bit(Faulty, &rdev2->flags)) { - s->handle_bad_blocks = 1; - atomic_inc(&rdev2->nr_pending); - } else - clear_bit(R5_WriteError, &dev->flags); - } - if (rdev && test_bit(R5_MadeGood, &dev->flags)) { - /* This flag does not apply to '.replacement' - * only to .rdev, so make sure to check that*/ - struct md_rdev *rdev2 = rcu_dereference( - conf->disks[i].rdev); - if (rdev2 && !test_bit(Faulty, &rdev2->flags)) { - s->handle_bad_blocks = 1; - atomic_inc(&rdev2->nr_pending); - } else - clear_bit(R5_MadeGood, &dev->flags); - } - if (test_bit(R5_MadeGoodRepl, &dev->flags)) { - struct md_rdev *rdev2 = rcu_dereference( - conf->disks[i].replacement); - if (rdev2 && !test_bit(Faulty, &rdev2->flags)) { - s->handle_bad_blocks = 1; - atomic_inc(&rdev2->nr_pending); - } else - clear_bit(R5_MadeGoodRepl, &dev->flags); - } - if (!test_bit(R5_Insync, &dev->flags)) { - /* The ReadError flag will just be confusing now */ - clear_bit(R5_ReadError, &dev->flags); - clear_bit(R5_ReWrite, &dev->flags); - } - if (test_bit(R5_ReadError, &dev->flags)) - clear_bit(R5_Insync, &dev->flags); - if (!test_bit(R5_Insync, &dev->flags)) { - if (s->failed < 2) - s->failed_num[s->failed] = i; - s->failed++; - if (rdev && !test_bit(Faulty, &rdev->flags)) - do_recovery = 1; - } - } - spin_unlock_irq(&conf->device_lock); - if (test_bit(STRIPE_SYNCING, &sh->state)) { - /* If there is a failed device being replaced, - * we must be recovering. - * else if we are after recovery_cp, we must be syncing - * else if MD_RECOVERY_REQUESTED is set, we also are syncing. - * else we can only be replacing - * sync and recovery both need to read all devices, and so - * use the same flag. - */ - if (do_recovery || - sh->sector >= conf->mddev->recovery_cp || - test_bit(MD_RECOVERY_REQUESTED, &(conf->mddev->recovery))) - s->syncing = 1; - else - s->replacing = 1; - } - rcu_read_unlock(); -} - -static void handle_stripe(struct stripe_head *sh) -{ - struct stripe_head_state s; - struct r5conf *conf = sh->raid_conf; - int i; - int prexor; - int disks = sh->disks; - struct r5dev *pdev, *qdev; - - clear_bit(STRIPE_HANDLE, &sh->state); - if (test_and_set_bit_lock(STRIPE_ACTIVE, &sh->state)) { - /* already being handled, ensure it gets handled - * again when current action finishes */ - set_bit(STRIPE_HANDLE, &sh->state); - return; - } - - if (test_and_clear_bit(STRIPE_SYNC_REQUESTED, &sh->state)) { - set_bit(STRIPE_SYNCING, &sh->state); - clear_bit(STRIPE_INSYNC, &sh->state); - } - clear_bit(STRIPE_DELAYED, &sh->state); - - pr_debug("handling stripe %llu, state=%#lx cnt=%d, " - "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n", - (unsigned long long)sh->sector, sh->state, - atomic_read(&sh->count), sh->pd_idx, sh->qd_idx, - sh->check_state, sh->reconstruct_state); - - analyse_stripe(sh, &s); - - if (s.handle_bad_blocks) { - set_bit(STRIPE_HANDLE, &sh->state); - goto finish; - } - - if (unlikely(s.blocked_rdev)) { - if (s.syncing || s.expanding || s.expanded || - s.replacing || s.to_write || s.written) { - set_bit(STRIPE_HANDLE, &sh->state); - goto finish; - } - /* There is nothing for the blocked_rdev to block */ - rdev_dec_pending(s.blocked_rdev, conf->mddev); - s.blocked_rdev = NULL; - } - - if (s.to_fill && !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) { - set_bit(STRIPE_OP_BIOFILL, &s.ops_request); - set_bit(STRIPE_BIOFILL_RUN, &sh->state); - } - - pr_debug("locked=%d uptodate=%d to_read=%d" - " to_write=%d failed=%d failed_num=%d,%d\n", - s.locked, s.uptodate, s.to_read, s.to_write, s.failed, - s.failed_num[0], s.failed_num[1]); - /* check if the array has lost more than max_degraded devices and, - * if so, some requests might need to be failed. - */ - if (s.failed > conf->max_degraded) { - sh->check_state = 0; - sh->reconstruct_state = 0; - if (s.to_read+s.to_write+s.written) - handle_failed_stripe(conf, sh, &s, disks, &s.return_bi); - if (s.syncing + s.replacing) - handle_failed_sync(conf, sh, &s); - } - - /* - * might be able to return some write requests if the parity blocks - * are safe, or on a failed drive - */ - pdev = &sh->dev[sh->pd_idx]; - s.p_failed = (s.failed >= 1 && s.failed_num[0] == sh->pd_idx) - || (s.failed >= 2 && s.failed_num[1] == sh->pd_idx); - qdev = &sh->dev[sh->qd_idx]; - s.q_failed = (s.failed >= 1 && s.failed_num[0] == sh->qd_idx) - || (s.failed >= 2 && s.failed_num[1] == sh->qd_idx) - || conf->level < 6; - - if (s.written && - (s.p_failed || ((test_bit(R5_Insync, &pdev->flags) - && !test_bit(R5_LOCKED, &pdev->flags) - && test_bit(R5_UPTODATE, &pdev->flags)))) && - (s.q_failed || ((test_bit(R5_Insync, &qdev->flags) - && !test_bit(R5_LOCKED, &qdev->flags) - && test_bit(R5_UPTODATE, &qdev->flags))))) - handle_stripe_clean_event(conf, sh, disks, &s.return_bi); - - /* Now we might consider reading some blocks, either to check/generate - * parity, or to satisfy requests - * or to load a block that is being partially written. - */ - if (s.to_read || s.non_overwrite - || (conf->level == 6 && s.to_write && s.failed) - || (s.syncing && (s.uptodate + s.compute < disks)) - || s.replacing - || s.expanding) - handle_stripe_fill(sh, &s, disks); - - /* Now we check to see if any write operations have recently - * completed - */ - prexor = 0; - if (sh->reconstruct_state == reconstruct_state_prexor_drain_result) - prexor = 1; - if (sh->reconstruct_state == reconstruct_state_drain_result || - sh->reconstruct_state == reconstruct_state_prexor_drain_result) { - sh->reconstruct_state = reconstruct_state_idle; - - /* All the 'written' buffers and the parity block are ready to - * be written back to disk - */ - BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags)); - BUG_ON(sh->qd_idx >= 0 && - !test_bit(R5_UPTODATE, &sh->dev[sh->qd_idx].flags)); - for (i = disks; i--; ) { - struct r5dev *dev = &sh->dev[i]; - if (test_bit(R5_LOCKED, &dev->flags) && - (i == sh->pd_idx || i == sh->qd_idx || - dev->written)) { - pr_debug("Writing block %d\n", i); - set_bit(R5_Wantwrite, &dev->flags); - if (prexor) - continue; - if (!test_bit(R5_Insync, &dev->flags) || - ((i == sh->pd_idx || i == sh->qd_idx) && - s.failed == 0)) - set_bit(STRIPE_INSYNC, &sh->state); - } - } - if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) - s.dec_preread_active = 1; - } - - /* Now to consider new write requests and what else, if anything - * should be read. We do not handle new writes when: - * 1/ A 'write' operation (copy+xor) is already in flight. - * 2/ A 'check' operation is in flight, as it may clobber the parity - * block. - */ - if (s.to_write && !sh->reconstruct_state && !sh->check_state) - handle_stripe_dirtying(conf, sh, &s, disks); - - /* maybe we need to check and possibly fix the parity for this stripe - * Any reads will already have been scheduled, so we just see if enough - * data is available. The parity check is held off while parity - * dependent operations are in flight. - */ - if (sh->check_state || - (s.syncing && s.locked == 0 && - !test_bit(STRIPE_COMPUTE_RUN, &sh->state) && - !test_bit(STRIPE_INSYNC, &sh->state))) { - if (conf->level == 6) - handle_parity_checks6(conf, sh, &s, disks); - else - handle_parity_checks5(conf, sh, &s, disks); - } - - if (s.replacing && s.locked == 0 - && !test_bit(STRIPE_INSYNC, &sh->state)) { - /* Write out to replacement devices where possible */ - for (i = 0; i < conf->raid_disks; i++) - if (test_bit(R5_UPTODATE, &sh->dev[i].flags) && - test_bit(R5_NeedReplace, &sh->dev[i].flags)) { - set_bit(R5_WantReplace, &sh->dev[i].flags); - set_bit(R5_LOCKED, &sh->dev[i].flags); - s.locked++; - } - set_bit(STRIPE_INSYNC, &sh->state); - } - if ((s.syncing || s.replacing) && s.locked == 0 && - test_bit(STRIPE_INSYNC, &sh->state)) { - md_done_sync(conf->mddev, STRIPE_SECTORS, 1); - clear_bit(STRIPE_SYNCING, &sh->state); - } - - /* If the failed drives are just a ReadError, then we might need - * to progress the repair/check process - */ - if (s.failed <= conf->max_degraded && !conf->mddev->ro) - for (i = 0; i < s.failed; i++) { - struct r5dev *dev = &sh->dev[s.failed_num[i]]; - if (test_bit(R5_ReadError, &dev->flags) - && !test_bit(R5_LOCKED, &dev->flags) - && test_bit(R5_UPTODATE, &dev->flags) - ) { - if (!test_bit(R5_ReWrite, &dev->flags)) { - set_bit(R5_Wantwrite, &dev->flags); - set_bit(R5_ReWrite, &dev->flags); - set_bit(R5_LOCKED, &dev->flags); - s.locked++; - } else { - /* let's read it back */ - set_bit(R5_Wantread, &dev->flags); - set_bit(R5_LOCKED, &dev->flags); - s.locked++; - } - } - } - - - /* Finish reconstruct operations initiated by the expansion process */ - if (sh->reconstruct_state == reconstruct_state_result) { - struct stripe_head *sh_src - = get_active_stripe(conf, sh->sector, 1, 1, 1); - if (sh_src && test_bit(STRIPE_EXPAND_SOURCE, &sh_src->state)) { - /* sh cannot be written until sh_src has been read. - * so arrange for sh to be delayed a little - */ - set_bit(STRIPE_DELAYED, &sh->state); - set_bit(STRIPE_HANDLE, &sh->state); - if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, - &sh_src->state)) - atomic_inc(&conf->preread_active_stripes); - release_stripe(sh_src); - goto finish; - } - if (sh_src) - release_stripe(sh_src); - - sh->reconstruct_state = reconstruct_state_idle; - clear_bit(STRIPE_EXPANDING, &sh->state); - for (i = conf->raid_disks; i--; ) { - set_bit(R5_Wantwrite, &sh->dev[i].flags); - set_bit(R5_LOCKED, &sh->dev[i].flags); - s.locked++; - } - } - - if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state) && - !sh->reconstruct_state) { - /* Need to write out all blocks after computing parity */ - sh->disks = conf->raid_disks; - stripe_set_idx(sh->sector, conf, 0, sh); - schedule_reconstruction(sh, &s, 1, 1); - } else if (s.expanded && !sh->reconstruct_state && s.locked == 0) { - clear_bit(STRIPE_EXPAND_READY, &sh->state); - atomic_dec(&conf->reshape_stripes); - wake_up(&conf->wait_for_overlap); - md_done_sync(conf->mddev, STRIPE_SECTORS, 1); - } - - if (s.expanding && s.locked == 0 && - !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) - handle_stripe_expansion(conf, sh); - -finish: - /* wait for this device to become unblocked */ - if (conf->mddev->external && unlikely(s.blocked_rdev)) - md_wait_for_blocked_rdev(s.blocked_rdev, conf->mddev); - - if (s.handle_bad_blocks) - for (i = disks; i--; ) { - struct md_rdev *rdev; - struct r5dev *dev = &sh->dev[i]; - if (test_and_clear_bit(R5_WriteError, &dev->flags)) { - /* We own a safe reference to the rdev */ - rdev = conf->disks[i].rdev; - if (!rdev_set_badblocks(rdev, sh->sector, - STRIPE_SECTORS, 0)) - md_error(conf->mddev, rdev); - rdev_dec_pending(rdev, conf->mddev); - } - if (test_and_clear_bit(R5_MadeGood, &dev->flags)) { - rdev = conf->disks[i].rdev; - rdev_clear_badblocks(rdev, sh->sector, - STRIPE_SECTORS); - rdev_dec_pending(rdev, conf->mddev); - } - if (test_and_clear_bit(R5_MadeGoodRepl, &dev->flags)) { - rdev = conf->disks[i].replacement; - if (!rdev) - /* rdev have been moved down */ - rdev = conf->disks[i].rdev; - rdev_clear_badblocks(rdev, sh->sector, - STRIPE_SECTORS); - rdev_dec_pending(rdev, conf->mddev); - } - } - - if (s.ops_request) - raid_run_ops(sh, s.ops_request); - - ops_run_io(sh, &s); - - if (s.dec_preread_active) { - /* We delay this until after ops_run_io so that if make_request - * is waiting on a flush, it won't continue until the writes - * have actually been submitted. - */ - atomic_dec(&conf->preread_active_stripes); - if (atomic_read(&conf->preread_active_stripes) < - IO_THRESHOLD) - md_wakeup_thread(conf->mddev->thread); - } - - return_io(s.return_bi); - - clear_bit_unlock(STRIPE_ACTIVE, &sh->state); -} - -static void raid5_activate_delayed(struct r5conf *conf) -{ - if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) { - while (!list_empty(&conf->delayed_list)) { - struct list_head *l = conf->delayed_list.next; - struct stripe_head *sh; - sh = list_entry(l, struct stripe_head, lru); - list_del_init(l); - clear_bit(STRIPE_DELAYED, &sh->state); - if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) - atomic_inc(&conf->preread_active_stripes); - list_add_tail(&sh->lru, &conf->hold_list); - } - } -} - -static void activate_bit_delay(struct r5conf *conf) -{ - /* device_lock is held */ - struct list_head head; - list_add(&head, &conf->bitmap_list); - list_del_init(&conf->bitmap_list); - while (!list_empty(&head)) { - struct stripe_head *sh = list_entry(head.next, struct stripe_head, lru); - list_del_init(&sh->lru); - atomic_inc(&sh->count); - __release_stripe(conf, sh); - } -} - -int md_raid5_congested(struct mddev *mddev, int bits) -{ - struct r5conf *conf = mddev->private; - - /* No difference between reads and writes. Just check - * how busy the stripe_cache is - */ - - if (conf->inactive_blocked) - return 1; - if (conf->quiesce) - return 1; - if (list_empty_careful(&conf->inactive_list)) - return 1; - - return 0; -} -EXPORT_SYMBOL_GPL(md_raid5_congested); - -static int raid5_congested(void *data, int bits) -{ - struct mddev *mddev = data; - - return mddev_congested(mddev, bits) || - md_raid5_congested(mddev, bits); -} - -/* We want read requests to align with chunks where possible, - * but write requests don't need to. - */ -static int raid5_mergeable_bvec(struct request_queue *q, - struct bvec_merge_data *bvm, - struct bio_vec *biovec) -{ - struct mddev *mddev = q->queuedata; - sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev); - int max; - unsigned int chunk_sectors = mddev->chunk_sectors; - unsigned int bio_sectors = bvm->bi_size >> 9; - - if ((bvm->bi_rw & 1) == WRITE) - return biovec->bv_len; /* always allow writes to be mergeable */ - - if (mddev->new_chunk_sectors < mddev->chunk_sectors) - chunk_sectors = mddev->new_chunk_sectors; - max = (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9; - if (max < 0) max = 0; - if (max <= biovec->bv_len && bio_sectors == 0) - return biovec->bv_len; - else - return max; -} - - -static int in_chunk_boundary(struct mddev *mddev, struct bio *bio) -{ - sector_t sector = bio->bi_sector + get_start_sect(bio->bi_bdev); - unsigned int chunk_sectors = mddev->chunk_sectors; - unsigned int bio_sectors = bio->bi_size >> 9; - - if (mddev->new_chunk_sectors < mddev->chunk_sectors) - chunk_sectors = mddev->new_chunk_sectors; - return chunk_sectors >= - ((sector & (chunk_sectors - 1)) + bio_sectors); -} - -/* - * add bio to the retry LIFO ( in O(1) ... we are in interrupt ) - * later sampled by raid5d. - */ -static void add_bio_to_retry(struct bio *bi,struct r5conf *conf) -{ - unsigned long flags; - - spin_lock_irqsave(&conf->device_lock, flags); - - bi->bi_next = conf->retry_read_aligned_list; - conf->retry_read_aligned_list = bi; - - spin_unlock_irqrestore(&conf->device_lock, flags); - md_wakeup_thread(conf->mddev->thread); -} - - -static struct bio *remove_bio_from_retry(struct r5conf *conf) -{ - struct bio *bi; - - bi = conf->retry_read_aligned; - if (bi) { - conf->retry_read_aligned = NULL; - return bi; - } - bi = conf->retry_read_aligned_list; - if(bi) { - conf->retry_read_aligned_list = bi->bi_next; - bi->bi_next = NULL; - /* - * this sets the active strip count to 1 and the processed - * strip count to zero (upper 8 bits) - */ - bi->bi_phys_segments = 1; /* biased count of active stripes */ - } - - return bi; -} - - -/* - * The "raid5_align_endio" should check if the read succeeded and if it - * did, call bio_endio on the original bio (having bio_put the new bio - * first). - * If the read failed.. - */ -static void raid5_align_endio(struct bio *bi, int error) -{ - struct bio* raid_bi = bi->bi_private; - struct mddev *mddev; - struct r5conf *conf; - int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); - struct md_rdev *rdev; - - bio_put(bi); - - rdev = (void*)raid_bi->bi_next; - raid_bi->bi_next = NULL; - mddev = rdev->mddev; - conf = mddev->private; - - rdev_dec_pending(rdev, conf->mddev); - - if (!error && uptodate) { - bio_endio(raid_bi, 0); - if (atomic_dec_and_test(&conf->active_aligned_reads)) - wake_up(&conf->wait_for_stripe); - return; - } - - - pr_debug("raid5_align_endio : io error...handing IO for a retry\n"); - - add_bio_to_retry(raid_bi, conf); -} - -static int bio_fits_rdev(struct bio *bi) -{ - struct request_queue *q = bdev_get_queue(bi->bi_bdev); - - if ((bi->bi_size>>9) > queue_max_sectors(q)) - return 0; - blk_recount_segments(q, bi); - if (bi->bi_phys_segments > queue_max_segments(q)) - return 0; - - if (q->merge_bvec_fn) - /* it's too hard to apply the merge_bvec_fn at this stage, - * just just give up - */ - return 0; - - return 1; -} - - -static int chunk_aligned_read(struct mddev *mddev, struct bio * raid_bio) -{ - struct r5conf *conf = mddev->private; - int dd_idx; - struct bio* align_bi; - struct md_rdev *rdev; - sector_t end_sector; - - if (!in_chunk_boundary(mddev, raid_bio)) { - pr_debug("chunk_aligned_read : non aligned\n"); - return 0; - } - /* - * use bio_clone_mddev to make a copy of the bio - */ - align_bi = bio_clone_mddev(raid_bio, GFP_NOIO, mddev); - if (!align_bi) - return 0; - /* - * set bi_end_io to a new function, and set bi_private to the - * original bio. - */ - align_bi->bi_end_io = raid5_align_endio; - align_bi->bi_private = raid_bio; - /* - * compute position - */ - align_bi->bi_sector = raid5_compute_sector(conf, raid_bio->bi_sector, - 0, - &dd_idx, NULL); - - end_sector = align_bi->bi_sector + (align_bi->bi_size >> 9); - rcu_read_lock(); - rdev = rcu_dereference(conf->disks[dd_idx].replacement); - if (!rdev || test_bit(Faulty, &rdev->flags) || - rdev->recovery_offset < end_sector) { - rdev = rcu_dereference(conf->disks[dd_idx].rdev); - if (rdev && - (test_bit(Faulty, &rdev->flags) || - !(test_bit(In_sync, &rdev->flags) || - rdev->recovery_offset >= end_sector))) - rdev = NULL; - } - if (rdev) { - sector_t first_bad; - int bad_sectors; - - atomic_inc(&rdev->nr_pending); - rcu_read_unlock(); - raid_bio->bi_next = (void*)rdev; - align_bi->bi_bdev = rdev->bdev; - align_bi->bi_flags &= ~(1 << BIO_SEG_VALID); - - if (!bio_fits_rdev(align_bi) || - is_badblock(rdev, align_bi->bi_sector, align_bi->bi_size>>9, - &first_bad, &bad_sectors)) { - /* too big in some way, or has a known bad block */ - bio_put(align_bi); - rdev_dec_pending(rdev, mddev); - return 0; - } - - /* No reshape active, so we can trust rdev->data_offset */ - align_bi->bi_sector += rdev->data_offset; - - spin_lock_irq(&conf->device_lock); - wait_event_lock_irq(conf->wait_for_stripe, - conf->quiesce == 0, - conf->device_lock, /* nothing */); - atomic_inc(&conf->active_aligned_reads); - spin_unlock_irq(&conf->device_lock); - - generic_make_request(align_bi); - return 1; - } else { - rcu_read_unlock(); - bio_put(align_bi); - return 0; - } -} - -/* __get_priority_stripe - get the next stripe to process - * - * Full stripe writes are allowed to pass preread active stripes up until - * the bypass_threshold is exceeded. In general the bypass_count - * increments when the handle_list is handled before the hold_list; however, it - * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a - * stripe with in flight i/o. The bypass_count will be reset when the - * head of the hold_list has changed, i.e. the head was promoted to the - * handle_list. - */ -static struct stripe_head *__get_priority_stripe(struct r5conf *conf) -{ - struct stripe_head *sh; - - pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n", - __func__, - list_empty(&conf->handle_list) ? "empty" : "busy", - list_empty(&conf->hold_list) ? "empty" : "busy", - atomic_read(&conf->pending_full_writes), conf->bypass_count); - - if (!list_empty(&conf->handle_list)) { - sh = list_entry(conf->handle_list.next, typeof(*sh), lru); - - if (list_empty(&conf->hold_list)) - conf->bypass_count = 0; - else if (!test_bit(STRIPE_IO_STARTED, &sh->state)) { - if (conf->hold_list.next == conf->last_hold) - conf->bypass_count++; - else { - conf->last_hold = conf->hold_list.next; - conf->bypass_count -= conf->bypass_threshold; - if (conf->bypass_count < 0) - conf->bypass_count = 0; - } - } - } else if (!list_empty(&conf->hold_list) && - ((conf->bypass_threshold && - conf->bypass_count > conf->bypass_threshold) || - atomic_read(&conf->pending_full_writes) == 0)) { - sh = list_entry(conf->hold_list.next, - typeof(*sh), lru); - conf->bypass_count -= conf->bypass_threshold; - if (conf->bypass_count < 0) - conf->bypass_count = 0; - } else - return NULL; - - list_del_init(&sh->lru); - atomic_inc(&sh->count); - BUG_ON(atomic_read(&sh->count) != 1); - return sh; -} - -static void make_request(struct mddev *mddev, struct bio * bi) -{ - struct r5conf *conf = mddev->private; - int dd_idx; - sector_t new_sector; - sector_t logical_sector, last_sector; - struct stripe_head *sh; - const int rw = bio_data_dir(bi); - int remaining; - int plugged; - - if (unlikely(bi->bi_rw & REQ_FLUSH)) { - md_flush_request(mddev, bi); - return; - } - - md_write_start(mddev, bi); - - if (rw == READ && - mddev->reshape_position == MaxSector && - chunk_aligned_read(mddev,bi)) - return; - - logical_sector = bi->bi_sector & ~((sector_t)STRIPE_SECTORS-1); - last_sector = bi->bi_sector + (bi->bi_size>>9); - bi->bi_next = NULL; - bi->bi_phys_segments = 1; /* over-loaded to count active stripes */ - - plugged = mddev_check_plugged(mddev); - for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) { - DEFINE_WAIT(w); - int disks, data_disks; - int previous; - - retry: - previous = 0; - disks = conf->raid_disks; - prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE); - if (unlikely(conf->reshape_progress != MaxSector)) { - /* spinlock is needed as reshape_progress may be - * 64bit on a 32bit platform, and so it might be - * possible to see a half-updated value - * Of course reshape_progress could change after - * the lock is dropped, so once we get a reference - * to the stripe that we think it is, we will have - * to check again. - */ - spin_lock_irq(&conf->device_lock); - if (mddev->delta_disks < 0 - ? logical_sector < conf->reshape_progress - : logical_sector >= conf->reshape_progress) { - disks = conf->previous_raid_disks; - previous = 1; - } else { - if (mddev->delta_disks < 0 - ? logical_sector < conf->reshape_safe - : logical_sector >= conf->reshape_safe) { - spin_unlock_irq(&conf->device_lock); - schedule(); - goto retry; - } - } - spin_unlock_irq(&conf->device_lock); - } - data_disks = disks - conf->max_degraded; - - new_sector = raid5_compute_sector(conf, logical_sector, - previous, - &dd_idx, NULL); - pr_debug("raid456: make_request, sector %llu logical %llu\n", - (unsigned long long)new_sector, - (unsigned long long)logical_sector); - - sh = get_active_stripe(conf, new_sector, previous, - (bi->bi_rw&RWA_MASK), 0); - if (sh) { - if (unlikely(previous)) { - /* expansion might have moved on while waiting for a - * stripe, so we must do the range check again. - * Expansion could still move past after this - * test, but as we are holding a reference to - * 'sh', we know that if that happens, - * STRIPE_EXPANDING will get set and the expansion - * won't proceed until we finish with the stripe. - */ - int must_retry = 0; - spin_lock_irq(&conf->device_lock); - if (mddev->delta_disks < 0 - ? logical_sector >= conf->reshape_progress - : logical_sector < conf->reshape_progress) - /* mismatch, need to try again */ - must_retry = 1; - spin_unlock_irq(&conf->device_lock); - if (must_retry) { - release_stripe(sh); - schedule(); - goto retry; - } - } - - if (rw == WRITE && - logical_sector >= mddev->suspend_lo && - logical_sector < mddev->suspend_hi) { - release_stripe(sh); - /* As the suspend_* range is controlled by - * userspace, we want an interruptible - * wait. - */ - flush_signals(current); - prepare_to_wait(&conf->wait_for_overlap, - &w, TASK_INTERRUPTIBLE); - if (logical_sector >= mddev->suspend_lo && - logical_sector < mddev->suspend_hi) - schedule(); - goto retry; - } - - if (test_bit(STRIPE_EXPANDING, &sh->state) || - !add_stripe_bio(sh, bi, dd_idx, rw)) { - /* Stripe is busy expanding or - * add failed due to overlap. Flush everything - * and wait a while - */ - md_wakeup_thread(mddev->thread); - release_stripe(sh); - schedule(); - goto retry; - } - finish_wait(&conf->wait_for_overlap, &w); - set_bit(STRIPE_HANDLE, &sh->state); - clear_bit(STRIPE_DELAYED, &sh->state); - if ((bi->bi_rw & REQ_SYNC) && - !test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) - atomic_inc(&conf->preread_active_stripes); - release_stripe(sh); - } else { - /* cannot get stripe for read-ahead, just give-up */ - clear_bit(BIO_UPTODATE, &bi->bi_flags); - finish_wait(&conf->wait_for_overlap, &w); - break; - } - - } - if (!plugged) - md_wakeup_thread(mddev->thread); - - spin_lock_irq(&conf->device_lock); - remaining = raid5_dec_bi_phys_segments(bi); - spin_unlock_irq(&conf->device_lock); - if (remaining == 0) { - - if ( rw == WRITE ) - md_write_end(mddev); - - bio_endio(bi, 0); - } -} - -static sector_t raid5_size(struct mddev *mddev, sector_t sectors, int raid_disks); - -static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *skipped) -{ - /* reshaping is quite different to recovery/resync so it is - * handled quite separately ... here. - * - * On each call to sync_request, we gather one chunk worth of - * destination stripes and flag them as expanding. - * Then we find all the source stripes and request reads. - * As the reads complete, handle_stripe will copy the data - * into the destination stripe and release that stripe. - */ - struct r5conf *conf = mddev->private; - struct stripe_head *sh; - sector_t first_sector, last_sector; - int raid_disks = conf->previous_raid_disks; - int data_disks = raid_disks - conf->max_degraded; - int new_data_disks = conf->raid_disks - conf->max_degraded; - int i; - int dd_idx; - sector_t writepos, readpos, safepos; - sector_t stripe_addr; - int reshape_sectors; - struct list_head stripes; - - if (sector_nr == 0) { - /* If restarting in the middle, skip the initial sectors */ - if (mddev->delta_disks < 0 && - conf->reshape_progress < raid5_size(mddev, 0, 0)) { - sector_nr = raid5_size(mddev, 0, 0) - - conf->reshape_progress; - } else if (mddev->delta_disks >= 0 && - conf->reshape_progress > 0) - sector_nr = conf->reshape_progress; - sector_div(sector_nr, new_data_disks); - if (sector_nr) { - mddev->curr_resync_completed = sector_nr; - sysfs_notify(&mddev->kobj, NULL, "sync_completed"); - *skipped = 1; - return sector_nr; - } - } - - /* We need to process a full chunk at a time. - * If old and new chunk sizes differ, we need to process the - * largest of these - */ - if (mddev->new_chunk_sectors > mddev->chunk_sectors) - reshape_sectors = mddev->new_chunk_sectors; - else - reshape_sectors = mddev->chunk_sectors; - - /* we update the metadata when there is more than 3Meg - * in the block range (that is rather arbitrary, should - * probably be time based) or when the data about to be - * copied would over-write the source of the data at - * the front of the range. - * i.e. one new_stripe along from reshape_progress new_maps - * to after where reshape_safe old_maps to - */ - writepos = conf->reshape_progress; - sector_div(writepos, new_data_disks); - readpos = conf->reshape_progress; - sector_div(readpos, data_disks); - safepos = conf->reshape_safe; - sector_div(safepos, data_disks); - if (mddev->delta_disks < 0) { - writepos -= min_t(sector_t, reshape_sectors, writepos); - readpos += reshape_sectors; - safepos += reshape_sectors; - } else { - writepos += reshape_sectors; - readpos -= min_t(sector_t, reshape_sectors, readpos); - safepos -= min_t(sector_t, reshape_sectors, safepos); - } - - /* 'writepos' is the most advanced device address we might write. - * 'readpos' is the least advanced device address we might read. - * 'safepos' is the least address recorded in the metadata as having - * been reshaped. - * If 'readpos' is behind 'writepos', then there is no way that we can - * ensure safety in the face of a crash - that must be done by userspace - * making a backup of the data. So in that case there is no particular - * rush to update metadata. - * Otherwise if 'safepos' is behind 'writepos', then we really need to - * update the metadata to advance 'safepos' to match 'readpos' so that - * we can be safe in the event of a crash. - * So we insist on updating metadata if safepos is behind writepos and - * readpos is beyond writepos. - * In any case, update the metadata every 10 seconds. - * Maybe that number should be configurable, but I'm not sure it is - * worth it.... maybe it could be a multiple of safemode_delay??? - */ - if ((mddev->delta_disks < 0 - ? (safepos > writepos && readpos < writepos) - : (safepos < writepos && readpos > writepos)) || - time_after(jiffies, conf->reshape_checkpoint + 10*HZ)) { - /* Cannot proceed until we've updated the superblock... */ - wait_event(conf->wait_for_overlap, - atomic_read(&conf->reshape_stripes)==0); - mddev->reshape_position = conf->reshape_progress; - mddev->curr_resync_completed = sector_nr; - conf->reshape_checkpoint = jiffies; - set_bit(MD_CHANGE_DEVS, &mddev->flags); - md_wakeup_thread(mddev->thread); - wait_event(mddev->sb_wait, mddev->flags == 0 || - kthread_should_stop()); - spin_lock_irq(&conf->device_lock); - conf->reshape_safe = mddev->reshape_position; - spin_unlock_irq(&conf->device_lock); - wake_up(&conf->wait_for_overlap); - sysfs_notify(&mddev->kobj, NULL, "sync_completed"); - } - - if (mddev->delta_disks < 0) { - BUG_ON(conf->reshape_progress == 0); - stripe_addr = writepos; - BUG_ON((mddev->dev_sectors & - ~((sector_t)reshape_sectors - 1)) - - reshape_sectors - stripe_addr - != sector_nr); - } else { - BUG_ON(writepos != sector_nr + reshape_sectors); - stripe_addr = sector_nr; - } - INIT_LIST_HEAD(&stripes); - for (i = 0; i < reshape_sectors; i += STRIPE_SECTORS) { - int j; - int skipped_disk = 0; - sh = get_active_stripe(conf, stripe_addr+i, 0, 0, 1); - set_bit(STRIPE_EXPANDING, &sh->state); - atomic_inc(&conf->reshape_stripes); - /* If any of this stripe is beyond the end of the old - * array, then we need to zero those blocks - */ - for (j=sh->disks; j--;) { - sector_t s; - if (j == sh->pd_idx) - continue; - if (conf->level == 6 && - j == sh->qd_idx) - continue; - s = compute_blocknr(sh, j, 0); - if (s < raid5_size(mddev, 0, 0)) { - skipped_disk = 1; - continue; - } - memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE); - set_bit(R5_Expanded, &sh->dev[j].flags); - set_bit(R5_UPTODATE, &sh->dev[j].flags); - } - if (!skipped_disk) { - set_bit(STRIPE_EXPAND_READY, &sh->state); - set_bit(STRIPE_HANDLE, &sh->state); - } - list_add(&sh->lru, &stripes); - } - spin_lock_irq(&conf->device_lock); - if (mddev->delta_disks < 0) - conf->reshape_progress -= reshape_sectors * new_data_disks; - else - conf->reshape_progress += reshape_sectors * new_data_disks; - spin_unlock_irq(&conf->device_lock); - /* Ok, those stripe are ready. We can start scheduling - * reads on the source stripes. - * The source stripes are determined by mapping the first and last - * block on the destination stripes. - */ - first_sector = - raid5_compute_sector(conf, stripe_addr*(new_data_disks), - 1, &dd_idx, NULL); - last_sector = - raid5_compute_sector(conf, ((stripe_addr+reshape_sectors) - * new_data_disks - 1), - 1, &dd_idx, NULL); - if (last_sector >= mddev->dev_sectors) - last_sector = mddev->dev_sectors - 1; - while (first_sector <= last_sector) { - sh = get_active_stripe(conf, first_sector, 1, 0, 1); - set_bit(STRIPE_EXPAND_SOURCE, &sh->state); - set_bit(STRIPE_HANDLE, &sh->state); - release_stripe(sh); - first_sector += STRIPE_SECTORS; - } - /* Now that the sources are clearly marked, we can release - * the destination stripes - */ - while (!list_empty(&stripes)) { - sh = list_entry(stripes.next, struct stripe_head, lru); - list_del_init(&sh->lru); - release_stripe(sh); - } - /* If this takes us to the resync_max point where we have to pause, - * then we need to write out the superblock. - */ - sector_nr += reshape_sectors; - if ((sector_nr - mddev->curr_resync_completed) * 2 - >= mddev->resync_max - mddev->curr_resync_completed) { - /* Cannot proceed until we've updated the superblock... */ - wait_event(conf->wait_for_overlap, - atomic_read(&conf->reshape_stripes) == 0); - mddev->reshape_position = conf->reshape_progress; - mddev->curr_resync_completed = sector_nr; - conf->reshape_checkpoint = jiffies; - set_bit(MD_CHANGE_DEVS, &mddev->flags); - md_wakeup_thread(mddev->thread); - wait_event(mddev->sb_wait, - !test_bit(MD_CHANGE_DEVS, &mddev->flags) - || kthread_should_stop()); - spin_lock_irq(&conf->device_lock); - conf->reshape_safe = mddev->reshape_position; - spin_unlock_irq(&conf->device_lock); - wake_up(&conf->wait_for_overlap); - sysfs_notify(&mddev->kobj, NULL, "sync_completed"); - } - return reshape_sectors; -} - -/* FIXME go_faster isn't used */ -static inline sector_t sync_request(struct mddev *mddev, sector_t sector_nr, int *skipped, int go_faster) -{ - struct r5conf *conf = mddev->private; - struct stripe_head *sh; - sector_t max_sector = mddev->dev_sectors; - sector_t sync_blocks; - int still_degraded = 0; - int i; - - if (sector_nr >= max_sector) { - /* just being told to finish up .. nothing much to do */ - - if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) { - end_reshape(conf); - return 0; - } - - if (mddev->curr_resync < max_sector) /* aborted */ - bitmap_end_sync(mddev->bitmap, mddev->curr_resync, - &sync_blocks, 1); - else /* completed sync */ - conf->fullsync = 0; - bitmap_close_sync(mddev->bitmap); - - return 0; - } - - /* Allow raid5_quiesce to complete */ - wait_event(conf->wait_for_overlap, conf->quiesce != 2); - - if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) - return reshape_request(mddev, sector_nr, skipped); - - /* No need to check resync_max as we never do more than one - * stripe, and as resync_max will always be on a chunk boundary, - * if the check in md_do_sync didn't fire, there is no chance - * of overstepping resync_max here - */ - - /* if there is too many failed drives and we are trying - * to resync, then assert that we are finished, because there is - * nothing we can do. - */ - if (mddev->degraded >= conf->max_degraded && - test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { - sector_t rv = mddev->dev_sectors - sector_nr; - *skipped = 1; - return rv; - } - if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) && - !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && - !conf->fullsync && sync_blocks >= STRIPE_SECTORS) { - /* we can skip this block, and probably more */ - sync_blocks /= STRIPE_SECTORS; - *skipped = 1; - return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */ - } - - bitmap_cond_end_sync(mddev->bitmap, sector_nr); - - sh = get_active_stripe(conf, sector_nr, 0, 1, 0); - if (sh == NULL) { - sh = get_active_stripe(conf, sector_nr, 0, 0, 0); - /* make sure we don't swamp the stripe cache if someone else - * is trying to get access - */ - schedule_timeout_uninterruptible(1); - } - /* Need to check if array will still be degraded after recovery/resync - * We don't need to check the 'failed' flag as when that gets set, - * recovery aborts. - */ - for (i = 0; i < conf->raid_disks; i++) - if (conf->disks[i].rdev == NULL) - still_degraded = 1; - - bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded); - - set_bit(STRIPE_SYNC_REQUESTED, &sh->state); - - handle_stripe(sh); - release_stripe(sh); - - return STRIPE_SECTORS; -} - -static int retry_aligned_read(struct r5conf *conf, struct bio *raid_bio) -{ - /* We may not be able to submit a whole bio at once as there - * may not be enough stripe_heads available. - * We cannot pre-allocate enough stripe_heads as we may need - * more than exist in the cache (if we allow ever large chunks). - * So we do one stripe head at a time and record in - * ->bi_hw_segments how many have been done. - * - * We *know* that this entire raid_bio is in one chunk, so - * it will be only one 'dd_idx' and only need one call to raid5_compute_sector. - */ - struct stripe_head *sh; - int dd_idx; - sector_t sector, logical_sector, last_sector; - int scnt = 0; - int remaining; - int handled = 0; - - logical_sector = raid_bio->bi_sector & ~((sector_t)STRIPE_SECTORS-1); - sector = raid5_compute_sector(conf, logical_sector, - 0, &dd_idx, NULL); - last_sector = raid_bio->bi_sector + (raid_bio->bi_size>>9); - - for (; logical_sector < last_sector; - logical_sector += STRIPE_SECTORS, - sector += STRIPE_SECTORS, - scnt++) { - - if (scnt < raid5_bi_hw_segments(raid_bio)) - /* already done this stripe */ - continue; - - sh = get_active_stripe(conf, sector, 0, 1, 0); - - if (!sh) { - /* failed to get a stripe - must wait */ - raid5_set_bi_hw_segments(raid_bio, scnt); - conf->retry_read_aligned = raid_bio; - return handled; - } - - if (!add_stripe_bio(sh, raid_bio, dd_idx, 0)) { - release_stripe(sh); - raid5_set_bi_hw_segments(raid_bio, scnt); - conf->retry_read_aligned = raid_bio; - return handled; - } - - handle_stripe(sh); - release_stripe(sh); - handled++; - } - spin_lock_irq(&conf->device_lock); - remaining = raid5_dec_bi_phys_segments(raid_bio); - spin_unlock_irq(&conf->device_lock); - if (remaining == 0) - bio_endio(raid_bio, 0); - if (atomic_dec_and_test(&conf->active_aligned_reads)) - wake_up(&conf->wait_for_stripe); - return handled; -} - - -/* - * This is our raid5 kernel thread. - * - * We scan the hash table for stripes which can be handled now. - * During the scan, completed stripes are saved for us by the interrupt - * handler, so that they will not have to wait for our next wakeup. - */ -static void raid5d(struct mddev *mddev) -{ - struct stripe_head *sh; - struct r5conf *conf = mddev->private; - int handled; - struct blk_plug plug; - - pr_debug("+++ raid5d active\n"); - - md_check_recovery(mddev); - - blk_start_plug(&plug); - handled = 0; - spin_lock_irq(&conf->device_lock); - while (1) { - struct bio *bio; - - if (atomic_read(&mddev->plug_cnt) == 0 && - !list_empty(&conf->bitmap_list)) { - /* Now is a good time to flush some bitmap updates */ - conf->seq_flush++; - spin_unlock_irq(&conf->device_lock); - bitmap_unplug(mddev->bitmap); - spin_lock_irq(&conf->device_lock); - conf->seq_write = conf->seq_flush; - activate_bit_delay(conf); - } - if (atomic_read(&mddev->plug_cnt) == 0) - raid5_activate_delayed(conf); - - while ((bio = remove_bio_from_retry(conf))) { - int ok; - spin_unlock_irq(&conf->device_lock); - ok = retry_aligned_read(conf, bio); - spin_lock_irq(&conf->device_lock); - if (!ok) - break; - handled++; - } - - sh = __get_priority_stripe(conf); - - if (!sh) - break; - spin_unlock_irq(&conf->device_lock); - - handled++; - handle_stripe(sh); - release_stripe(sh); - cond_resched(); - - if (mddev->flags & ~(1<<MD_CHANGE_PENDING)) - md_check_recovery(mddev); - - spin_lock_irq(&conf->device_lock); - } - pr_debug("%d stripes handled\n", handled); - - spin_unlock_irq(&conf->device_lock); - - async_tx_issue_pending_all(); - blk_finish_plug(&plug); - - pr_debug("--- raid5d inactive\n"); -} - -static ssize_t -raid5_show_stripe_cache_size(struct mddev *mddev, char *page) -{ - struct r5conf *conf = mddev->private; - if (conf) - return sprintf(page, "%d\n", conf->max_nr_stripes); - else - return 0; -} - -int -raid5_set_cache_size(struct mddev *mddev, int size) -{ - struct r5conf *conf = mddev->private; - int err; - - if (size <= 16 || size > 32768) - return -EINVAL; - while (size < conf->max_nr_stripes) { - if (drop_one_stripe(conf)) - conf->max_nr_stripes--; - else - break; - } - err = md_allow_write(mddev); - if (err) - return err; - while (size > conf->max_nr_stripes) { - if (grow_one_stripe(conf)) - conf->max_nr_stripes++; - else break; - } - return 0; -} -EXPORT_SYMBOL(raid5_set_cache_size); - -static ssize_t -raid5_store_stripe_cache_size(struct mddev *mddev, const char *page, size_t len) -{ - struct r5conf *conf = mddev->private; - unsigned long new; - int err; - - if (len >= PAGE_SIZE) - return -EINVAL; - if (!conf) - return -ENODEV; - - if (strict_strtoul(page, 10, &new)) - return -EINVAL; - err = raid5_set_cache_size(mddev, new); - if (err) - return err; - return len; -} - -static struct md_sysfs_entry -raid5_stripecache_size = __ATTR(stripe_cache_size, S_IRUGO | S_IWUSR, - raid5_show_stripe_cache_size, - raid5_store_stripe_cache_size); - -static ssize_t -raid5_show_preread_threshold(struct mddev *mddev, char *page) -{ - struct r5conf *conf = mddev->private; - if (conf) - return sprintf(page, "%d\n", conf->bypass_threshold); - else - return 0; -} - -static ssize_t -raid5_store_preread_threshold(struct mddev *mddev, const char *page, size_t len) -{ - struct r5conf *conf = mddev->private; - unsigned long new; - if (len >= PAGE_SIZE) - return -EINVAL; - if (!conf) - return -ENODEV; - - if (strict_strtoul(page, 10, &new)) - return -EINVAL; - if (new > conf->max_nr_stripes) - return -EINVAL; - conf->bypass_threshold = new; - return len; -} - -static struct md_sysfs_entry -raid5_preread_bypass_threshold = __ATTR(preread_bypass_threshold, - S_IRUGO | S_IWUSR, - raid5_show_preread_threshold, - raid5_store_preread_threshold); - -static ssize_t -stripe_cache_active_show(struct mddev *mddev, char *page) -{ - struct r5conf *conf = mddev->private; - if (conf) - return sprintf(page, "%d\n", atomic_read(&conf->active_stripes)); - else - return 0; -} - -static struct md_sysfs_entry -raid5_stripecache_active = __ATTR_RO(stripe_cache_active); - -static struct attribute *raid5_attrs[] = { - &raid5_stripecache_size.attr, - &raid5_stripecache_active.attr, - &raid5_preread_bypass_threshold.attr, - NULL, -}; -static struct attribute_group raid5_attrs_group = { - .name = NULL, - .attrs = raid5_attrs, -}; - -static sector_t -raid5_size(struct mddev *mddev, sector_t sectors, int raid_disks) -{ - struct r5conf *conf = mddev->private; - - if (!sectors) - sectors = mddev->dev_sectors; - if (!raid_disks) - /* size is defined by the smallest of previous and new size */ - raid_disks = min(conf->raid_disks, conf->previous_raid_disks); - - sectors &= ~((sector_t)mddev->chunk_sectors - 1); - sectors &= ~((sector_t)mddev->new_chunk_sectors - 1); - return sectors * (raid_disks - conf->max_degraded); -} - -static void raid5_free_percpu(struct r5conf *conf) -{ - struct raid5_percpu *percpu; - unsigned long cpu; - - if (!conf->percpu) - return; - - get_online_cpus(); - for_each_possible_cpu(cpu) { - percpu = per_cpu_ptr(conf->percpu, cpu); - safe_put_page(percpu->spare_page); - kfree(percpu->scribble); - } -#ifdef CONFIG_HOTPLUG_CPU - unregister_cpu_notifier(&conf->cpu_notify); -#endif - put_online_cpus(); - - free_percpu(conf->percpu); -} - -static void free_conf(struct r5conf *conf) -{ - shrink_stripes(conf); - raid5_free_percpu(conf); - kfree(conf->disks); - kfree(conf->stripe_hashtbl); - kfree(conf); -} - -#ifdef CONFIG_HOTPLUG_CPU -static int raid456_cpu_notify(struct notifier_block *nfb, unsigned long action, - void *hcpu) -{ - struct r5conf *conf = container_of(nfb, struct r5conf, cpu_notify); - long cpu = (long)hcpu; - struct raid5_percpu *percpu = per_cpu_ptr(conf->percpu, cpu); - - switch (action) { - case CPU_UP_PREPARE: - case CPU_UP_PREPARE_FROZEN: - if (conf->level == 6 && !percpu->spare_page) - percpu->spare_page = alloc_page(GFP_KERNEL); - if (!percpu->scribble) - percpu->scribble = kmalloc(conf->scribble_len, GFP_KERNEL); - - if (!percpu->scribble || - (conf->level == 6 && !percpu->spare_page)) { - safe_put_page(percpu->spare_page); - kfree(percpu->scribble); - pr_err("%s: failed memory allocation for cpu%ld\n", - __func__, cpu); - return notifier_from_errno(-ENOMEM); - } - break; - case CPU_DEAD: - case CPU_DEAD_FROZEN: - safe_put_page(percpu->spare_page); - kfree(percpu->scribble); - percpu->spare_page = NULL; - percpu->scribble = NULL; - break; - default: - break; - } - return NOTIFY_OK; -} -#endif - -static int raid5_alloc_percpu(struct r5conf *conf) -{ - unsigned long cpu; - struct page *spare_page; - struct raid5_percpu __percpu *allcpus; - void *scribble; - int err; - - allcpus = alloc_percpu(struct raid5_percpu); - if (!allcpus) - return -ENOMEM; - conf->percpu = allcpus; - - get_online_cpus(); - err = 0; - for_each_present_cpu(cpu) { - if (conf->level == 6) { - spare_page = alloc_page(GFP_KERNEL); - if (!spare_page) { - err = -ENOMEM; - break; - } - per_cpu_ptr(conf->percpu, cpu)->spare_page = spare_page; - } - scribble = kmalloc(conf->scribble_len, GFP_KERNEL); - if (!scribble) { - err = -ENOMEM; - break; - } - per_cpu_ptr(conf->percpu, cpu)->scribble = scribble; - } -#ifdef CONFIG_HOTPLUG_CPU - conf->cpu_notify.notifier_call = raid456_cpu_notify; - conf->cpu_notify.priority = 0; - if (err == 0) - err = register_cpu_notifier(&conf->cpu_notify); -#endif - put_online_cpus(); - - return err; -} - -static struct r5conf *setup_conf(struct mddev *mddev) -{ - struct r5conf *conf; - int raid_disk, memory, max_disks; - struct md_rdev *rdev; - struct disk_info *disk; - - if (mddev->new_level != 5 - && mddev->new_level != 4 - && mddev->new_level != 6) { - printk(KERN_ERR "md/raid:%s: raid level not set to 4/5/6 (%d)\n", - mdname(mddev), mddev->new_level); - return ERR_PTR(-EIO); - } - if ((mddev->new_level == 5 - && !algorithm_valid_raid5(mddev->new_layout)) || - (mddev->new_level == 6 - && !algorithm_valid_raid6(mddev->new_layout))) { - printk(KERN_ERR "md/raid:%s: layout %d not supported\n", - mdname(mddev), mddev->new_layout); - return ERR_PTR(-EIO); - } - if (mddev->new_level == 6 && mddev->raid_disks < 4) { - printk(KERN_ERR "md/raid:%s: not enough configured devices (%d, minimum 4)\n", - mdname(mddev), mddev->raid_disks); - return ERR_PTR(-EINVAL); - } - - if (!mddev->new_chunk_sectors || - (mddev->new_chunk_sectors << 9) % PAGE_SIZE || - !is_power_of_2(mddev->new_chunk_sectors)) { - printk(KERN_ERR "md/raid:%s: invalid chunk size %d\n", - mdname(mddev), mddev->new_chunk_sectors << 9); - return ERR_PTR(-EINVAL); - } - - conf = kzalloc(sizeof(struct r5conf), GFP_KERNEL); - if (conf == NULL) - goto abort; - spin_lock_init(&conf->device_lock); - init_waitqueue_head(&conf->wait_for_stripe); - init_waitqueue_head(&conf->wait_for_overlap); - INIT_LIST_HEAD(&conf->handle_list); - INIT_LIST_HEAD(&conf->hold_list); - INIT_LIST_HEAD(&conf->delayed_list); - INIT_LIST_HEAD(&conf->bitmap_list); - INIT_LIST_HEAD(&conf->inactive_list); - atomic_set(&conf->active_stripes, 0); - atomic_set(&conf->preread_active_stripes, 0); - atomic_set(&conf->active_aligned_reads, 0); - conf->bypass_threshold = BYPASS_THRESHOLD; - conf->recovery_disabled = mddev->recovery_disabled - 1; - - conf->raid_disks = mddev->raid_disks; - if (mddev->reshape_position == MaxSector) - conf->previous_raid_disks = mddev->raid_disks; - else - conf->previous_raid_disks = mddev->raid_disks - mddev->delta_disks; - max_disks = max(conf->raid_disks, conf->previous_raid_disks); - conf->scribble_len = scribble_len(max_disks); - - conf->disks = kzalloc(max_disks * sizeof(struct disk_info), - GFP_KERNEL); - if (!conf->disks) - goto abort; - - conf->mddev = mddev; - - if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL) - goto abort; - - conf->level = mddev->new_level; - if (raid5_alloc_percpu(conf) != 0) - goto abort; - - pr_debug("raid456: run(%s) called.\n", mdname(mddev)); - - rdev_for_each(rdev, mddev) { - raid_disk = rdev->raid_disk; - if (raid_disk >= max_disks - || raid_disk < 0) - continue; - disk = conf->disks + raid_disk; - - if (test_bit(Replacement, &rdev->flags)) { - if (disk->replacement) - goto abort; - disk->replacement = rdev; - } else { - if (disk->rdev) - goto abort; - disk->rdev = rdev; - } - - if (test_bit(In_sync, &rdev->flags)) { - char b[BDEVNAME_SIZE]; - printk(KERN_INFO "md/raid:%s: device %s operational as raid" - " disk %d\n", - mdname(mddev), bdevname(rdev->bdev, b), raid_disk); - } else if (rdev->saved_raid_disk != raid_disk) - /* Cannot rely on bitmap to complete recovery */ - conf->fullsync = 1; - } - - conf->chunk_sectors = mddev->new_chunk_sectors; - conf->level = mddev->new_level; - if (conf->level == 6) - conf->max_degraded = 2; - else - conf->max_degraded = 1; - conf->algorithm = mddev->new_layout; - conf->max_nr_stripes = NR_STRIPES; - conf->reshape_progress = mddev->reshape_position; - if (conf->reshape_progress != MaxSector) { - conf->prev_chunk_sectors = mddev->chunk_sectors; - conf->prev_algo = mddev->layout; - } - - memory = conf->max_nr_stripes * (sizeof(struct stripe_head) + - max_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024; - if (grow_stripes(conf, conf->max_nr_stripes)) { - printk(KERN_ERR - "md/raid:%s: couldn't allocate %dkB for buffers\n", - mdname(mddev), memory); - goto abort; - } else - printk(KERN_INFO "md/raid:%s: allocated %dkB\n", - mdname(mddev), memory); - - conf->thread = md_register_thread(raid5d, mddev, NULL); - if (!conf->thread) { - printk(KERN_ERR - "md/raid:%s: couldn't allocate thread.\n", - mdname(mddev)); - goto abort; - } - - return conf; - - abort: - if (conf) { - free_conf(conf); - return ERR_PTR(-EIO); - } else - return ERR_PTR(-ENOMEM); -} - - -static int only_parity(int raid_disk, int algo, int raid_disks, int max_degraded) -{ - switch (algo) { - case ALGORITHM_PARITY_0: - if (raid_disk < max_degraded) - return 1; - break; - case ALGORITHM_PARITY_N: - if (raid_disk >= raid_disks - max_degraded) - return 1; - break; - case ALGORITHM_PARITY_0_6: - if (raid_disk == 0 || - raid_disk == raid_disks - 1) - return 1; - break; - case ALGORITHM_LEFT_ASYMMETRIC_6: - case ALGORITHM_RIGHT_ASYMMETRIC_6: - case ALGORITHM_LEFT_SYMMETRIC_6: - case ALGORITHM_RIGHT_SYMMETRIC_6: - if (raid_disk == raid_disks - 1) - return 1; - } - return 0; -} - -static int run(struct mddev *mddev) -{ - struct r5conf *conf; - int working_disks = 0; - int dirty_parity_disks = 0; - struct md_rdev *rdev; - sector_t reshape_offset = 0; - int i; - - if (mddev->recovery_cp != MaxSector) - printk(KERN_NOTICE "md/raid:%s: not clean" - " -- starting background reconstruction\n", - mdname(mddev)); - if (mddev->reshape_position != MaxSector) { - /* Check that we can continue the reshape. - * Currently only disks can change, it must - * increase, and we must be past the point where - * a stripe over-writes itself - */ - sector_t here_new, here_old; - int old_disks; - int max_degraded = (mddev->level == 6 ? 2 : 1); - - if (mddev->new_level != mddev->level) { - printk(KERN_ERR "md/raid:%s: unsupported reshape " - "required - aborting.\n", - mdname(mddev)); - return -EINVAL; - } - old_disks = mddev->raid_disks - mddev->delta_disks; - /* reshape_position must be on a new-stripe boundary, and one - * further up in new geometry must map after here in old - * geometry. - */ - here_new = mddev->reshape_position; - if (sector_div(here_new, mddev->new_chunk_sectors * - (mddev->raid_disks - max_degraded))) { - printk(KERN_ERR "md/raid:%s: reshape_position not " - "on a stripe boundary\n", mdname(mddev)); - return -EINVAL; - } - reshape_offset = here_new * mddev->new_chunk_sectors; - /* here_new is the stripe we will write to */ - here_old = mddev->reshape_position; - sector_div(here_old, mddev->chunk_sectors * - (old_disks-max_degraded)); - /* here_old is the first stripe that we might need to read - * from */ - if (mddev->delta_disks == 0) { - /* We cannot be sure it is safe to start an in-place - * reshape. It is only safe if user-space if monitoring - * and taking constant backups. - * mdadm always starts a situation like this in - * readonly mode so it can take control before - * allowing any writes. So just check for that. - */ - if ((here_new * mddev->new_chunk_sectors != - here_old * mddev->chunk_sectors) || - mddev->ro == 0) { - printk(KERN_ERR "md/raid:%s: in-place reshape must be started" - " in read-only mode - aborting\n", - mdname(mddev)); - return -EINVAL; - } - } else if (mddev->delta_disks < 0 - ? (here_new * mddev->new_chunk_sectors <= - here_old * mddev->chunk_sectors) - : (here_new * mddev->new_chunk_sectors >= - here_old * mddev->chunk_sectors)) { - /* Reading from the same stripe as writing to - bad */ - printk(KERN_ERR "md/raid:%s: reshape_position too early for " - "auto-recovery - aborting.\n", - mdname(mddev)); - return -EINVAL; - } - printk(KERN_INFO "md/raid:%s: reshape will continue\n", - mdname(mddev)); - /* OK, we should be able to continue; */ - } else { - BUG_ON(mddev->level != mddev->new_level); - BUG_ON(mddev->layout != mddev->new_layout); - BUG_ON(mddev->chunk_sectors != mddev->new_chunk_sectors); - BUG_ON(mddev->delta_disks != 0); - } - - if (mddev->private == NULL) - conf = setup_conf(mddev); - else - conf = mddev->private; - - if (IS_ERR(conf)) - return PTR_ERR(conf); - - mddev->thread = conf->thread; - conf->thread = NULL; - mddev->private = conf; - - for (i = 0; i < conf->raid_disks && conf->previous_raid_disks; - i++) { - rdev = conf->disks[i].rdev; - if (!rdev && conf->disks[i].replacement) { - /* The replacement is all we have yet */ - rdev = conf->disks[i].replacement; - conf->disks[i].replacement = NULL; - clear_bit(Replacement, &rdev->flags); - conf->disks[i].rdev = rdev; - } - if (!rdev) - continue; - if (conf->disks[i].replacement && - conf->reshape_progress != MaxSector) { - /* replacements and reshape simply do not mix. */ - printk(KERN_ERR "md: cannot handle concurrent " - "replacement and reshape.\n"); - goto abort; - } - if (test_bit(In_sync, &rdev->flags)) { - working_disks++; - continue; - } - /* This disc is not fully in-sync. However if it - * just stored parity (beyond the recovery_offset), - * when we don't need to be concerned about the - * array being dirty. - * When reshape goes 'backwards', we never have - * partially completed devices, so we only need - * to worry about reshape going forwards. - */ - /* Hack because v0.91 doesn't store recovery_offset properly. */ - if (mddev->major_version == 0 && - mddev->minor_version > 90) - rdev->recovery_offset = reshape_offset; - - if (rdev->recovery_offset < reshape_offset) { - /* We need to check old and new layout */ - if (!only_parity(rdev->raid_disk, - conf->algorithm, - conf->raid_disks, - conf->max_degraded)) - continue; - } - if (!only_parity(rdev->raid_disk, - conf->prev_algo, - conf->previous_raid_disks, - conf->max_degraded)) - continue; - dirty_parity_disks++; - } - - /* - * 0 for a fully functional array, 1 or 2 for a degraded array. - */ - mddev->degraded = calc_degraded(conf); - - if (has_failed(conf)) { - printk(KERN_ERR "md/raid:%s: not enough operational devices" - " (%d/%d failed)\n", - mdname(mddev), mddev->degraded, conf->raid_disks); - goto abort; - } - - /* device size must be a multiple of chunk size */ - mddev->dev_sectors &= ~(mddev->chunk_sectors - 1); - mddev->resync_max_sectors = mddev->dev_sectors; - - if (mddev->degraded > dirty_parity_disks && - mddev->recovery_cp != MaxSector) { - if (mddev->ok_start_degraded) - printk(KERN_WARNING - "md/raid:%s: starting dirty degraded array" - " - data corruption possible.\n", - mdname(mddev)); - else { - printk(KERN_ERR - "md/raid:%s: cannot start dirty degraded array.\n", - mdname(mddev)); - goto abort; - } - } - - if (mddev->degraded == 0) - printk(KERN_INFO "md/raid:%s: raid level %d active with %d out of %d" - " devices, algorithm %d\n", mdname(mddev), conf->level, - mddev->raid_disks-mddev->degraded, mddev->raid_disks, - mddev->new_layout); - else - printk(KERN_ALERT "md/raid:%s: raid level %d active with %d" - " out of %d devices, algorithm %d\n", - mdname(mddev), conf->level, - mddev->raid_disks - mddev->degraded, - mddev->raid_disks, mddev->new_layout); - - print_raid5_conf(conf); - - if (conf->reshape_progress != MaxSector) { - conf->reshape_safe = conf->reshape_progress; - atomic_set(&conf->reshape_stripes, 0); - clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); - clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); - set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); - set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); - mddev->sync_thread = md_register_thread(md_do_sync, mddev, - "reshape"); - } - - - /* Ok, everything is just fine now */ - if (mddev->to_remove == &raid5_attrs_group) - mddev->to_remove = NULL; - else if (mddev->kobj.sd && - sysfs_create_group(&mddev->kobj, &raid5_attrs_group)) - printk(KERN_WARNING - "raid5: failed to create sysfs attributes for %s\n", - mdname(mddev)); - md_set_array_sectors(mddev, raid5_size(mddev, 0, 0)); - - if (mddev->queue) { - int chunk_size; - /* read-ahead size must cover two whole stripes, which - * is 2 * (datadisks) * chunksize where 'n' is the - * number of raid devices - */ - int data_disks = conf->previous_raid_disks - conf->max_degraded; - int stripe = data_disks * - ((mddev->chunk_sectors << 9) / PAGE_SIZE); - if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe) - mddev->queue->backing_dev_info.ra_pages = 2 * stripe; - - blk_queue_merge_bvec(mddev->queue, raid5_mergeable_bvec); - - mddev->queue->backing_dev_info.congested_data = mddev; - mddev->queue->backing_dev_info.congested_fn = raid5_congested; - - chunk_size = mddev->chunk_sectors << 9; - blk_queue_io_min(mddev->queue, chunk_size); - blk_queue_io_opt(mddev->queue, chunk_size * - (conf->raid_disks - conf->max_degraded)); - - rdev_for_each(rdev, mddev) - disk_stack_limits(mddev->gendisk, rdev->bdev, - rdev->data_offset << 9); - } - - return 0; -abort: - md_unregister_thread(&mddev->thread); - print_raid5_conf(conf); - free_conf(conf); - mddev->private = NULL; - printk(KERN_ALERT "md/raid:%s: failed to run raid set.\n", mdname(mddev)); - return -EIO; -} - -static int stop(struct mddev *mddev) -{ - struct r5conf *conf = mddev->private; - - md_unregister_thread(&mddev->thread); - if (mddev->queue) - mddev->queue->backing_dev_info.congested_fn = NULL; - free_conf(conf); - mddev->private = NULL; - mddev->to_remove = &raid5_attrs_group; - return 0; -} - -static void status(struct seq_file *seq, struct mddev *mddev) -{ - struct r5conf *conf = mddev->private; - int i; - - seq_printf(seq, " level %d, %dk chunk, algorithm %d", mddev->level, - mddev->chunk_sectors / 2, mddev->layout); - seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->raid_disks - mddev->degraded); - for (i = 0; i < conf->raid_disks; i++) - seq_printf (seq, "%s", - conf->disks[i].rdev && - test_bit(In_sync, &conf->disks[i].rdev->flags) ? "U" : "_"); - seq_printf (seq, "]"); -} - -static void print_raid5_conf (struct r5conf *conf) -{ - int i; - struct disk_info *tmp; - - printk(KERN_DEBUG "RAID conf printout:\n"); - if (!conf) { - printk("(conf==NULL)\n"); - return; - } - printk(KERN_DEBUG " --- level:%d rd:%d wd:%d\n", conf->level, - conf->raid_disks, - conf->raid_disks - conf->mddev->degraded); - - for (i = 0; i < conf->raid_disks; i++) { - char b[BDEVNAME_SIZE]; - tmp = conf->disks + i; - if (tmp->rdev) - printk(KERN_DEBUG " disk %d, o:%d, dev:%s\n", - i, !test_bit(Faulty, &tmp->rdev->flags), - bdevname(tmp->rdev->bdev, b)); - } -} - -static int raid5_spare_active(struct mddev *mddev) -{ - int i; - struct r5conf *conf = mddev->private; - struct disk_info *tmp; - int count = 0; - unsigned long flags; - - for (i = 0; i < conf->raid_disks; i++) { - tmp = conf->disks + i; - if (tmp->replacement - && tmp->replacement->recovery_offset == MaxSector - && !test_bit(Faulty, &tmp->replacement->flags) - && !test_and_set_bit(In_sync, &tmp->replacement->flags)) { - /* Replacement has just become active. */ - if (!tmp->rdev - || !test_and_clear_bit(In_sync, &tmp->rdev->flags)) - count++; - if (tmp->rdev) { - /* Replaced device not technically faulty, - * but we need to be sure it gets removed - * and never re-added. - */ - set_bit(Faulty, &tmp->rdev->flags); - sysfs_notify_dirent_safe( - tmp->rdev->sysfs_state); - } - sysfs_notify_dirent_safe(tmp->replacement->sysfs_state); - } else if (tmp->rdev - && tmp->rdev->recovery_offset == MaxSector - && !test_bit(Faulty, &tmp->rdev->flags) - && !test_and_set_bit(In_sync, &tmp->rdev->flags)) { - count++; - sysfs_notify_dirent_safe(tmp->rdev->sysfs_state); - } - } - spin_lock_irqsave(&conf->device_lock, flags); - mddev->degraded = calc_degraded(conf); - spin_unlock_irqrestore(&conf->device_lock, flags); - print_raid5_conf(conf); - return count; -} - -static int raid5_remove_disk(struct mddev *mddev, struct md_rdev *rdev) -{ - struct r5conf *conf = mddev->private; - int err = 0; - int number = rdev->raid_disk; - struct md_rdev **rdevp; - struct disk_info *p = conf->disks + number; - - print_raid5_conf(conf); - if (rdev == p->rdev) - rdevp = &p->rdev; - else if (rdev == p->replacement) - rdevp = &p->replacement; - else - return 0; - - if (number >= conf->raid_disks && - conf->reshape_progress == MaxSector) - clear_bit(In_sync, &rdev->flags); - - if (test_bit(In_sync, &rdev->flags) || - atomic_read(&rdev->nr_pending)) { - err = -EBUSY; - goto abort; - } - /* Only remove non-faulty devices if recovery - * isn't possible. - */ - if (!test_bit(Faulty, &rdev->flags) && - mddev->recovery_disabled != conf->recovery_disabled && - !has_failed(conf) && - (!p->replacement || p->replacement == rdev) && - number < conf->raid_disks) { - err = -EBUSY; - goto abort; - } - *rdevp = NULL; - synchronize_rcu(); - if (atomic_read(&rdev->nr_pending)) { - /* lost the race, try later */ - err = -EBUSY; - *rdevp = rdev; - } else if (p->replacement) { - /* We must have just cleared 'rdev' */ - p->rdev = p->replacement; - clear_bit(Replacement, &p->replacement->flags); - smp_mb(); /* Make sure other CPUs may see both as identical - * but will never see neither - if they are careful - */ - p->replacement = NULL; - clear_bit(WantReplacement, &rdev->flags); - } else - /* We might have just removed the Replacement as faulty- - * clear the bit just in case - */ - clear_bit(WantReplacement, &rdev->flags); -abort: - - print_raid5_conf(conf); - return err; -} - -static int raid5_add_disk(struct mddev *mddev, struct md_rdev *rdev) -{ - struct r5conf *conf = mddev->private; - int err = -EEXIST; - int disk; - struct disk_info *p; - int first = 0; - int last = conf->raid_disks - 1; - - if (mddev->recovery_disabled == conf->recovery_disabled) - return -EBUSY; - - if (rdev->saved_raid_disk < 0 && has_failed(conf)) - /* no point adding a device */ - return -EINVAL; - - if (rdev->raid_disk >= 0) - first = last = rdev->raid_disk; - - /* - * find the disk ... but prefer rdev->saved_raid_disk - * if possible. - */ - if (rdev->saved_raid_disk >= 0 && - rdev->saved_raid_disk >= first && - conf->disks[rdev->saved_raid_disk].rdev == NULL) - disk = rdev->saved_raid_disk; - else - disk = first; - for ( ; disk <= last ; disk++) { - p = conf->disks + disk; - if (p->rdev == NULL) { - clear_bit(In_sync, &rdev->flags); - rdev->raid_disk = disk; - err = 0; - if (rdev->saved_raid_disk != disk) - conf->fullsync = 1; - rcu_assign_pointer(p->rdev, rdev); - break; - } - if (test_bit(WantReplacement, &p->rdev->flags) && - p->replacement == NULL) { - clear_bit(In_sync, &rdev->flags); - set_bit(Replacement, &rdev->flags); - rdev->raid_disk = disk; - err = 0; - conf->fullsync = 1; - rcu_assign_pointer(p->replacement, rdev); - break; - } - } - print_raid5_conf(conf); - return err; -} - -static int raid5_resize(struct mddev *mddev, sector_t sectors) -{ - /* no resync is happening, and there is enough space - * on all devices, so we can resize. - * We need to make sure resync covers any new space. - * If the array is shrinking we should possibly wait until - * any io in the removed space completes, but it hardly seems - * worth it. - */ - sectors &= ~((sector_t)mddev->chunk_sectors - 1); - md_set_array_sectors(mddev, raid5_size(mddev, sectors, - mddev->raid_disks)); - if (mddev->array_sectors > - raid5_size(mddev, sectors, mddev->raid_disks)) - return -EINVAL; - set_capacity(mddev->gendisk, mddev->array_sectors); - revalidate_disk(mddev->gendisk); - if (sectors > mddev->dev_sectors && - mddev->recovery_cp > mddev->dev_sectors) { - mddev->recovery_cp = mddev->dev_sectors; - set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); - } - mddev->dev_sectors = sectors; - mddev->resync_max_sectors = sectors; - return 0; -} - -static int check_stripe_cache(struct mddev *mddev) -{ - /* Can only proceed if there are plenty of stripe_heads. - * We need a minimum of one full stripe,, and for sensible progress - * it is best to have about 4 times that. - * If we require 4 times, then the default 256 4K stripe_heads will - * allow for chunk sizes up to 256K, which is probably OK. - * If the chunk size is greater, user-space should request more - * stripe_heads first. - */ - struct r5conf *conf = mddev->private; - if (((mddev->chunk_sectors << 9) / STRIPE_SIZE) * 4 - > conf->max_nr_stripes || - ((mddev->new_chunk_sectors << 9) / STRIPE_SIZE) * 4 - > conf->max_nr_stripes) { - printk(KERN_WARNING "md/raid:%s: reshape: not enough stripes. Needed %lu\n", - mdname(mddev), - ((max(mddev->chunk_sectors, mddev->new_chunk_sectors) << 9) - / STRIPE_SIZE)*4); - return 0; - } - return 1; -} - -static int check_reshape(struct mddev *mddev) -{ - struct r5conf *conf = mddev->private; - - if (mddev->delta_disks == 0 && - mddev->new_layout == mddev->layout && - mddev->new_chunk_sectors == mddev->chunk_sectors) - return 0; /* nothing to do */ - if (mddev->bitmap) - /* Cannot grow a bitmap yet */ - return -EBUSY; - if (has_failed(conf)) - return -EINVAL; - if (mddev->delta_disks < 0) { - /* We might be able to shrink, but the devices must - * be made bigger first. - * For raid6, 4 is the minimum size. - * Otherwise 2 is the minimum - */ - int min = 2; - if (mddev->level == 6) - min = 4; - if (mddev->raid_disks + mddev->delta_disks < min) - return -EINVAL; - } - - if (!check_stripe_cache(mddev)) - return -ENOSPC; - - return resize_stripes(conf, conf->raid_disks + mddev->delta_disks); -} - -static int raid5_start_reshape(struct mddev *mddev) -{ - struct r5conf *conf = mddev->private; - struct md_rdev *rdev; - int spares = 0; - unsigned long flags; - - if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) - return -EBUSY; - - if (!check_stripe_cache(mddev)) - return -ENOSPC; - - rdev_for_each(rdev, mddev) - if (!test_bit(In_sync, &rdev->flags) - && !test_bit(Faulty, &rdev->flags)) - spares++; - - if (spares - mddev->degraded < mddev->delta_disks - conf->max_degraded) - /* Not enough devices even to make a degraded array - * of that size - */ - return -EINVAL; - - /* Refuse to reduce size of the array. Any reductions in - * array size must be through explicit setting of array_size - * attribute. - */ - if (raid5_size(mddev, 0, conf->raid_disks + mddev->delta_disks) - < mddev->array_sectors) { - printk(KERN_ERR "md/raid:%s: array size must be reduced " - "before number of disks\n", mdname(mddev)); - return -EINVAL; - } - - atomic_set(&conf->reshape_stripes, 0); - spin_lock_irq(&conf->device_lock); - conf->previous_raid_disks = conf->raid_disks; - conf->raid_disks += mddev->delta_disks; - conf->prev_chunk_sectors = conf->chunk_sectors; - conf->chunk_sectors = mddev->new_chunk_sectors; - conf->prev_algo = conf->algorithm; - conf->algorithm = mddev->new_layout; - if (mddev->delta_disks < 0) - conf->reshape_progress = raid5_size(mddev, 0, 0); - else - conf->reshape_progress = 0; - conf->reshape_safe = conf->reshape_progress; - conf->generation++; - spin_unlock_irq(&conf->device_lock); - - /* Add some new drives, as many as will fit. - * We know there are enough to make the newly sized array work. - * Don't add devices if we are reducing the number of - * devices in the array. This is because it is not possible - * to correctly record the "partially reconstructed" state of - * such devices during the reshape and confusion could result. - */ - if (mddev->delta_disks >= 0) { - rdev_for_each(rdev, mddev) - if (rdev->raid_disk < 0 && - !test_bit(Faulty, &rdev->flags)) { - if (raid5_add_disk(mddev, rdev) == 0) { - if (rdev->raid_disk - >= conf->previous_raid_disks) - set_bit(In_sync, &rdev->flags); - else - rdev->recovery_offset = 0; - - if (sysfs_link_rdev(mddev, rdev)) - /* Failure here is OK */; - } - } else if (rdev->raid_disk >= conf->previous_raid_disks - && !test_bit(Faulty, &rdev->flags)) { - /* This is a spare that was manually added */ - set_bit(In_sync, &rdev->flags); - } - - /* When a reshape changes the number of devices, - * ->degraded is measured against the larger of the - * pre and post number of devices. - */ - spin_lock_irqsave(&conf->device_lock, flags); - mddev->degraded = calc_degraded(conf); - spin_unlock_irqrestore(&conf->device_lock, flags); - } - mddev->raid_disks = conf->raid_disks; - mddev->reshape_position = conf->reshape_progress; - set_bit(MD_CHANGE_DEVS, &mddev->flags); - - clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); - clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); - set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); - set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); - mddev->sync_thread = md_register_thread(md_do_sync, mddev, - "reshape"); - if (!mddev->sync_thread) { - mddev->recovery = 0; - spin_lock_irq(&conf->device_lock); - mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks; - conf->reshape_progress = MaxSector; - mddev->reshape_position = MaxSector; - spin_unlock_irq(&conf->device_lock); - return -EAGAIN; - } - conf->reshape_checkpoint = jiffies; - md_wakeup_thread(mddev->sync_thread); - md_new_event(mddev); - return 0; -} - -/* This is called from the reshape thread and should make any - * changes needed in 'conf' - */ -static void end_reshape(struct r5conf *conf) -{ - - if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) { - - spin_lock_irq(&conf->device_lock); - conf->previous_raid_disks = conf->raid_disks; - conf->reshape_progress = MaxSector; - spin_unlock_irq(&conf->device_lock); - wake_up(&conf->wait_for_overlap); - - /* read-ahead size must cover two whole stripes, which is - * 2 * (datadisks) * chunksize where 'n' is the number of raid devices - */ - if (conf->mddev->queue) { - int data_disks = conf->raid_disks - conf->max_degraded; - int stripe = data_disks * ((conf->chunk_sectors << 9) - / PAGE_SIZE); - if (conf->mddev->queue->backing_dev_info.ra_pages < 2 * stripe) - conf->mddev->queue->backing_dev_info.ra_pages = 2 * stripe; - } - } -} - -/* This is called from the raid5d thread with mddev_lock held. - * It makes config changes to the device. - */ -static void raid5_finish_reshape(struct mddev *mddev) -{ - struct r5conf *conf = mddev->private; - - if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) { - - if (mddev->delta_disks > 0) { - md_set_array_sectors(mddev, raid5_size(mddev, 0, 0)); - set_capacity(mddev->gendisk, mddev->array_sectors); - revalidate_disk(mddev->gendisk); - } else { - int d; - spin_lock_irq(&conf->device_lock); - mddev->degraded = calc_degraded(conf); - spin_unlock_irq(&conf->device_lock); - for (d = conf->raid_disks ; - d < conf->raid_disks - mddev->delta_disks; - d++) { - struct md_rdev *rdev = conf->disks[d].rdev; - if (rdev && - raid5_remove_disk(mddev, rdev) == 0) { - sysfs_unlink_rdev(mddev, rdev); - rdev->raid_disk = -1; - } - } - } - mddev->layout = conf->algorithm; - mddev->chunk_sectors = conf->chunk_sectors; - mddev->reshape_position = MaxSector; - mddev->delta_disks = 0; - } -} - -static void raid5_quiesce(struct mddev *mddev, int state) -{ - struct r5conf *conf = mddev->private; - - switch(state) { - case 2: /* resume for a suspend */ - wake_up(&conf->wait_for_overlap); - break; - - case 1: /* stop all writes */ - spin_lock_irq(&conf->device_lock); - /* '2' tells resync/reshape to pause so that all - * active stripes can drain - */ - conf->quiesce = 2; - wait_event_lock_irq(conf->wait_for_stripe, - atomic_read(&conf->active_stripes) == 0 && - atomic_read(&conf->active_aligned_reads) == 0, - conf->device_lock, /* nothing */); - conf->quiesce = 1; - spin_unlock_irq(&conf->device_lock); - /* allow reshape to continue */ - wake_up(&conf->wait_for_overlap); - break; - - case 0: /* re-enable writes */ - spin_lock_irq(&conf->device_lock); - conf->quiesce = 0; - wake_up(&conf->wait_for_stripe); - wake_up(&conf->wait_for_overlap); - spin_unlock_irq(&conf->device_lock); - break; - } -} - - -static void *raid45_takeover_raid0(struct mddev *mddev, int level) -{ - struct r0conf *raid0_conf = mddev->private; - sector_t sectors; - - /* for raid0 takeover only one zone is supported */ - if (raid0_conf->nr_strip_zones > 1) { - printk(KERN_ERR "md/raid:%s: cannot takeover raid0 with more than one zone.\n", - mdname(mddev)); - return ERR_PTR(-EINVAL); - } - - sectors = raid0_conf->strip_zone[0].zone_end; - sector_div(sectors, raid0_conf->strip_zone[0].nb_dev); - mddev->dev_sectors = sectors; - mddev->new_level = level; - mddev->new_layout = ALGORITHM_PARITY_N; - mddev->new_chunk_sectors = mddev->chunk_sectors; - mddev->raid_disks += 1; - mddev->delta_disks = 1; - /* make sure it will be not marked as dirty */ - mddev->recovery_cp = MaxSector; - - return setup_conf(mddev); -} - - -static void *raid5_takeover_raid1(struct mddev *mddev) -{ - int chunksect; - - if (mddev->raid_disks != 2 || - mddev->degraded > 1) - return ERR_PTR(-EINVAL); - - /* Should check if there are write-behind devices? */ - - chunksect = 64*2; /* 64K by default */ - - /* The array must be an exact multiple of chunksize */ - while (chunksect && (mddev->array_sectors & (chunksect-1))) - chunksect >>= 1; - - if ((chunksect<<9) < STRIPE_SIZE) - /* array size does not allow a suitable chunk size */ - return ERR_PTR(-EINVAL); - - mddev->new_level = 5; - mddev->new_layout = ALGORITHM_LEFT_SYMMETRIC; - mddev->new_chunk_sectors = chunksect; - - return setup_conf(mddev); -} - -static void *raid5_takeover_raid6(struct mddev *mddev) -{ - int new_layout; - - switch (mddev->layout) { - case ALGORITHM_LEFT_ASYMMETRIC_6: - new_layout = ALGORITHM_LEFT_ASYMMETRIC; - break; - case ALGORITHM_RIGHT_ASYMMETRIC_6: - new_layout = ALGORITHM_RIGHT_ASYMMETRIC; - break; - case ALGORITHM_LEFT_SYMMETRIC_6: - new_layout = ALGORITHM_LEFT_SYMMETRIC; - break; - case ALGORITHM_RIGHT_SYMMETRIC_6: - new_layout = ALGORITHM_RIGHT_SYMMETRIC; - break; - case ALGORITHM_PARITY_0_6: - new_layout = ALGORITHM_PARITY_0; - break; - case ALGORITHM_PARITY_N: - new_layout = ALGORITHM_PARITY_N; - break; - default: - return ERR_PTR(-EINVAL); - } - mddev->new_level = 5; - mddev->new_layout = new_layout; - mddev->delta_disks = -1; - mddev->raid_disks -= 1; - return setup_conf(mddev); -} - - -static int raid5_check_reshape(struct mddev *mddev) -{ - /* For a 2-drive array, the layout and chunk size can be changed - * immediately as not restriping is needed. - * For larger arrays we record the new value - after validation - * to be used by a reshape pass. - */ - struct r5conf *conf = mddev->private; - int new_chunk = mddev->new_chunk_sectors; - - if (mddev->new_layout >= 0 && !algorithm_valid_raid5(mddev->new_layout)) - return -EINVAL; - if (new_chunk > 0) { - if (!is_power_of_2(new_chunk)) - return -EINVAL; - if (new_chunk < (PAGE_SIZE>>9)) - return -EINVAL; - if (mddev->array_sectors & (new_chunk-1)) - /* not factor of array size */ - return -EINVAL; - } - - /* They look valid */ - - if (mddev->raid_disks == 2) { - /* can make the change immediately */ - if (mddev->new_layout >= 0) { - conf->algorithm = mddev->new_layout; - mddev->layout = mddev->new_layout; - } - if (new_chunk > 0) { - conf->chunk_sectors = new_chunk ; - mddev->chunk_sectors = new_chunk; - } - set_bit(MD_CHANGE_DEVS, &mddev->flags); - md_wakeup_thread(mddev->thread); - } - return check_reshape(mddev); -} - -static int raid6_check_reshape(struct mddev *mddev) -{ - int new_chunk = mddev->new_chunk_sectors; - - if (mddev->new_layout >= 0 && !algorithm_valid_raid6(mddev->new_layout)) - return -EINVAL; - if (new_chunk > 0) { - if (!is_power_of_2(new_chunk)) - return -EINVAL; - if (new_chunk < (PAGE_SIZE >> 9)) - return -EINVAL; - if (mddev->array_sectors & (new_chunk-1)) - /* not factor of array size */ - return -EINVAL; - } - - /* They look valid */ - return check_reshape(mddev); -} - -static void *raid5_takeover(struct mddev *mddev) -{ - /* raid5 can take over: - * raid0 - if there is only one strip zone - make it a raid4 layout - * raid1 - if there are two drives. We need to know the chunk size - * raid4 - trivial - just use a raid4 layout. - * raid6 - Providing it is a *_6 layout - */ - if (mddev->level == 0) - return raid45_takeover_raid0(mddev, 5); - if (mddev->level == 1) - return raid5_takeover_raid1(mddev); - if (mddev->level == 4) { - mddev->new_layout = ALGORITHM_PARITY_N; - mddev->new_level = 5; - return setup_conf(mddev); - } - if (mddev->level == 6) - return raid5_takeover_raid6(mddev); - - return ERR_PTR(-EINVAL); -} - -static void *raid4_takeover(struct mddev *mddev) -{ - /* raid4 can take over: - * raid0 - if there is only one strip zone - * raid5 - if layout is right - */ - if (mddev->level == 0) - return raid45_takeover_raid0(mddev, 4); - if (mddev->level == 5 && - mddev->layout == ALGORITHM_PARITY_N) { - mddev->new_layout = 0; - mddev->new_level = 4; - return setup_conf(mddev); - } - return ERR_PTR(-EINVAL); -} - -static struct md_personality raid5_personality; - -static void *raid6_takeover(struct mddev *mddev) -{ - /* Currently can only take over a raid5. We map the - * personality to an equivalent raid6 personality - * with the Q block at the end. - */ - int new_layout; - - if (mddev->pers != &raid5_personality) - return ERR_PTR(-EINVAL); - if (mddev->degraded > 1) - return ERR_PTR(-EINVAL); - if (mddev->raid_disks > 253) - return ERR_PTR(-EINVAL); - if (mddev->raid_disks < 3) - return ERR_PTR(-EINVAL); - - switch (mddev->layout) { - case ALGORITHM_LEFT_ASYMMETRIC: - new_layout = ALGORITHM_LEFT_ASYMMETRIC_6; - break; - case ALGORITHM_RIGHT_ASYMMETRIC: - new_layout = ALGORITHM_RIGHT_ASYMMETRIC_6; - break; - case ALGORITHM_LEFT_SYMMETRIC: - new_layout = ALGORITHM_LEFT_SYMMETRIC_6; - break; - case ALGORITHM_RIGHT_SYMMETRIC: - new_layout = ALGORITHM_RIGHT_SYMMETRIC_6; - break; - case ALGORITHM_PARITY_0: - new_layout = ALGORITHM_PARITY_0_6; - break; - case ALGORITHM_PARITY_N: - new_layout = ALGORITHM_PARITY_N; - break; - default: - return ERR_PTR(-EINVAL); - } - mddev->new_level = 6; - mddev->new_layout = new_layout; - mddev->delta_disks = 1; - mddev->raid_disks += 1; - return setup_conf(mddev); -} - - -static struct md_personality raid6_personality = -{ - .name = "raid6", - .level = 6, - .owner = THIS_MODULE, - .make_request = make_request, - .run = run, - .stop = stop, - .status = status, - .error_handler = error, - .hot_add_disk = raid5_add_disk, - .hot_remove_disk= raid5_remove_disk, - .spare_active = raid5_spare_active, - .sync_request = sync_request, - .resize = raid5_resize, - .size = raid5_size, - .check_reshape = raid6_check_reshape, - .start_reshape = raid5_start_reshape, - .finish_reshape = raid5_finish_reshape, - .quiesce = raid5_quiesce, - .takeover = raid6_takeover, -}; -static struct md_personality raid5_personality = -{ - .name = "raid5", - .level = 5, - .owner = THIS_MODULE, - .make_request = make_request, - .run = run, - .stop = stop, - .status = status, - .error_handler = error, - .hot_add_disk = raid5_add_disk, - .hot_remove_disk= raid5_remove_disk, - .spare_active = raid5_spare_active, - .sync_request = sync_request, - .resize = raid5_resize, - .size = raid5_size, - .check_reshape = raid5_check_reshape, - .start_reshape = raid5_start_reshape, - .finish_reshape = raid5_finish_reshape, - .quiesce = raid5_quiesce, - .takeover = raid5_takeover, -}; - -static struct md_personality raid4_personality = -{ - .name = "raid4", - .level = 4, - .owner = THIS_MODULE, - .make_request = make_request, - .run = run, - .stop = stop, - .status = status, - .error_handler = error, - .hot_add_disk = raid5_add_disk, - .hot_remove_disk= raid5_remove_disk, - .spare_active = raid5_spare_active, - .sync_request = sync_request, - .resize = raid5_resize, - .size = raid5_size, - .check_reshape = raid5_check_reshape, - .start_reshape = raid5_start_reshape, - .finish_reshape = raid5_finish_reshape, - .quiesce = raid5_quiesce, - .takeover = raid4_takeover, -}; - -static int __init raid5_init(void) -{ - register_md_personality(&raid6_personality); - register_md_personality(&raid5_personality); - register_md_personality(&raid4_personality); - return 0; -} - -static void raid5_exit(void) -{ - unregister_md_personality(&raid6_personality); - unregister_md_personality(&raid5_personality); - unregister_md_personality(&raid4_personality); -} - -module_init(raid5_init); -module_exit(raid5_exit); -MODULE_LICENSE("GPL"); -MODULE_DESCRIPTION("RAID4/5/6 (striping with parity) personality for MD"); -MODULE_ALIAS("md-personality-4"); /* RAID5 */ -MODULE_ALIAS("md-raid5"); -MODULE_ALIAS("md-raid4"); -MODULE_ALIAS("md-level-5"); -MODULE_ALIAS("md-level-4"); -MODULE_ALIAS("md-personality-8"); /* RAID6 */ -MODULE_ALIAS("md-raid6"); -MODULE_ALIAS("md-level-6"); - -/* This used to be two separate modules, they were: */ -MODULE_ALIAS("raid5"); -MODULE_ALIAS("raid6"); |