diff options
Diffstat (limited to 'drivers/block/drbd/drbd_worker.c')
| -rw-r--r-- | drivers/block/drbd/drbd_worker.c | 1723 |
1 files changed, 1723 insertions, 0 deletions
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c new file mode 100644 index 00000000..4d3e6f62 --- /dev/null +++ b/drivers/block/drbd/drbd_worker.c @@ -0,0 +1,1723 @@ +/* + drbd_worker.c + + This file is part of DRBD by Philipp Reisner and Lars Ellenberg. + + Copyright (C) 2001-2008, LINBIT Information Technologies GmbH. + Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>. + Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>. + + drbd 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. + + drbd is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with drbd; see the file COPYING. If not, write to + the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. + + */ + +#include <linux/module.h> +#include <linux/drbd.h> +#include <linux/sched.h> +#include <linux/wait.h> +#include <linux/mm.h> +#include <linux/memcontrol.h> +#include <linux/mm_inline.h> +#include <linux/slab.h> +#include <linux/random.h> +#include <linux/string.h> +#include <linux/scatterlist.h> + +#include "drbd_int.h" +#include "drbd_req.h" + +static int w_make_ov_request(struct drbd_conf *mdev, struct drbd_work *w, int cancel); +static int w_make_resync_request(struct drbd_conf *mdev, + struct drbd_work *w, int cancel); + + + +/* endio handlers: + * drbd_md_io_complete (defined here) + * drbd_endio_pri (defined here) + * drbd_endio_sec (defined here) + * bm_async_io_complete (defined in drbd_bitmap.c) + * + * For all these callbacks, note the following: + * The callbacks will be called in irq context by the IDE drivers, + * and in Softirqs/Tasklets/BH context by the SCSI drivers. + * Try to get the locking right :) + * + */ + + +/* About the global_state_lock + Each state transition on an device holds a read lock. In case we have + to evaluate the sync after dependencies, we grab a write lock, because + we need stable states on all devices for that. */ +rwlock_t global_state_lock; + +/* used for synchronous meta data and bitmap IO + * submitted by drbd_md_sync_page_io() + */ +void drbd_md_io_complete(struct bio *bio, int error) +{ + struct drbd_md_io *md_io; + + md_io = (struct drbd_md_io *)bio->bi_private; + md_io->error = error; + + complete(&md_io->event); +} + +/* reads on behalf of the partner, + * "submitted" by the receiver + */ +void drbd_endio_read_sec_final(struct drbd_epoch_entry *e) __releases(local) +{ + unsigned long flags = 0; + struct drbd_conf *mdev = e->mdev; + + D_ASSERT(e->block_id != ID_VACANT); + + spin_lock_irqsave(&mdev->req_lock, flags); + mdev->read_cnt += e->size >> 9; + list_del(&e->w.list); + if (list_empty(&mdev->read_ee)) + wake_up(&mdev->ee_wait); + if (test_bit(__EE_WAS_ERROR, &e->flags)) + __drbd_chk_io_error(mdev, false); + spin_unlock_irqrestore(&mdev->req_lock, flags); + + drbd_queue_work(&mdev->data.work, &e->w); + put_ldev(mdev); +} + +/* writes on behalf of the partner, or resync writes, + * "submitted" by the receiver, final stage. */ +static void drbd_endio_write_sec_final(struct drbd_epoch_entry *e) __releases(local) +{ + unsigned long flags = 0; + struct drbd_conf *mdev = e->mdev; + sector_t e_sector; + int do_wake; + int is_syncer_req; + int do_al_complete_io; + + D_ASSERT(e->block_id != ID_VACANT); + + /* after we moved e to done_ee, + * we may no longer access it, + * it may be freed/reused already! + * (as soon as we release the req_lock) */ + e_sector = e->sector; + do_al_complete_io = e->flags & EE_CALL_AL_COMPLETE_IO; + is_syncer_req = is_syncer_block_id(e->block_id); + + spin_lock_irqsave(&mdev->req_lock, flags); + mdev->writ_cnt += e->size >> 9; + list_del(&e->w.list); /* has been on active_ee or sync_ee */ + list_add_tail(&e->w.list, &mdev->done_ee); + + /* No hlist_del_init(&e->collision) here, we did not send the Ack yet, + * neither did we wake possibly waiting conflicting requests. + * done from "drbd_process_done_ee" within the appropriate w.cb + * (e_end_block/e_end_resync_block) or from _drbd_clear_done_ee */ + + do_wake = is_syncer_req + ? list_empty(&mdev->sync_ee) + : list_empty(&mdev->active_ee); + + if (test_bit(__EE_WAS_ERROR, &e->flags)) + __drbd_chk_io_error(mdev, false); + spin_unlock_irqrestore(&mdev->req_lock, flags); + + if (is_syncer_req) + drbd_rs_complete_io(mdev, e_sector); + + if (do_wake) + wake_up(&mdev->ee_wait); + + if (do_al_complete_io) + drbd_al_complete_io(mdev, e_sector); + + wake_asender(mdev); + put_ldev(mdev); +} + +/* writes on behalf of the partner, or resync writes, + * "submitted" by the receiver. + */ +void drbd_endio_sec(struct bio *bio, int error) +{ + struct drbd_epoch_entry *e = bio->bi_private; + struct drbd_conf *mdev = e->mdev; + int uptodate = bio_flagged(bio, BIO_UPTODATE); + int is_write = bio_data_dir(bio) == WRITE; + + if (error && __ratelimit(&drbd_ratelimit_state)) + dev_warn(DEV, "%s: error=%d s=%llus\n", + is_write ? "write" : "read", error, + (unsigned long long)e->sector); + if (!error && !uptodate) { + if (__ratelimit(&drbd_ratelimit_state)) + dev_warn(DEV, "%s: setting error to -EIO s=%llus\n", + is_write ? "write" : "read", + (unsigned long long)e->sector); + /* strange behavior of some lower level drivers... + * fail the request by clearing the uptodate flag, + * but do not return any error?! */ + error = -EIO; + } + + if (error) + set_bit(__EE_WAS_ERROR, &e->flags); + + bio_put(bio); /* no need for the bio anymore */ + if (atomic_dec_and_test(&e->pending_bios)) { + if (is_write) + drbd_endio_write_sec_final(e); + else + drbd_endio_read_sec_final(e); + } +} + +/* read, readA or write requests on R_PRIMARY coming from drbd_make_request + */ +void drbd_endio_pri(struct bio *bio, int error) +{ + unsigned long flags; + struct drbd_request *req = bio->bi_private; + struct drbd_conf *mdev = req->mdev; + struct bio_and_error m; + enum drbd_req_event what; + int uptodate = bio_flagged(bio, BIO_UPTODATE); + + if (!error && !uptodate) { + dev_warn(DEV, "p %s: setting error to -EIO\n", + bio_data_dir(bio) == WRITE ? "write" : "read"); + /* strange behavior of some lower level drivers... + * fail the request by clearing the uptodate flag, + * but do not return any error?! */ + error = -EIO; + } + + /* to avoid recursion in __req_mod */ + if (unlikely(error)) { + what = (bio_data_dir(bio) == WRITE) + ? write_completed_with_error + : (bio_rw(bio) == READ) + ? read_completed_with_error + : read_ahead_completed_with_error; + } else + what = completed_ok; + + bio_put(req->private_bio); + req->private_bio = ERR_PTR(error); + + /* not req_mod(), we need irqsave here! */ + spin_lock_irqsave(&mdev->req_lock, flags); + __req_mod(req, what, &m); + spin_unlock_irqrestore(&mdev->req_lock, flags); + + if (m.bio) + complete_master_bio(mdev, &m); +} + +int w_read_retry_remote(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_request *req = container_of(w, struct drbd_request, w); + + /* We should not detach for read io-error, + * but try to WRITE the P_DATA_REPLY to the failed location, + * to give the disk the chance to relocate that block */ + + spin_lock_irq(&mdev->req_lock); + if (cancel || mdev->state.pdsk != D_UP_TO_DATE) { + _req_mod(req, read_retry_remote_canceled); + spin_unlock_irq(&mdev->req_lock); + return 1; + } + spin_unlock_irq(&mdev->req_lock); + + return w_send_read_req(mdev, w, 0); +} + +void drbd_csum_ee(struct drbd_conf *mdev, struct crypto_hash *tfm, struct drbd_epoch_entry *e, void *digest) +{ + struct hash_desc desc; + struct scatterlist sg; + struct page *page = e->pages; + struct page *tmp; + unsigned len; + + desc.tfm = tfm; + desc.flags = 0; + + sg_init_table(&sg, 1); + crypto_hash_init(&desc); + + while ((tmp = page_chain_next(page))) { + /* all but the last page will be fully used */ + sg_set_page(&sg, page, PAGE_SIZE, 0); + crypto_hash_update(&desc, &sg, sg.length); + page = tmp; + } + /* and now the last, possibly only partially used page */ + len = e->size & (PAGE_SIZE - 1); + sg_set_page(&sg, page, len ?: PAGE_SIZE, 0); + crypto_hash_update(&desc, &sg, sg.length); + crypto_hash_final(&desc, digest); +} + +void drbd_csum_bio(struct drbd_conf *mdev, struct crypto_hash *tfm, struct bio *bio, void *digest) +{ + struct hash_desc desc; + struct scatterlist sg; + struct bio_vec *bvec; + int i; + + desc.tfm = tfm; + desc.flags = 0; + + sg_init_table(&sg, 1); + crypto_hash_init(&desc); + + __bio_for_each_segment(bvec, bio, i, 0) { + sg_set_page(&sg, bvec->bv_page, bvec->bv_len, bvec->bv_offset); + crypto_hash_update(&desc, &sg, sg.length); + } + crypto_hash_final(&desc, digest); +} + +/* TODO merge common code with w_e_end_ov_req */ +int w_e_send_csum(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_epoch_entry *e = container_of(w, struct drbd_epoch_entry, w); + int digest_size; + void *digest; + int ok = 1; + + D_ASSERT(e->block_id == DRBD_MAGIC + 0xbeef); + + if (unlikely(cancel)) + goto out; + + if (likely((e->flags & EE_WAS_ERROR) != 0)) + goto out; + + digest_size = crypto_hash_digestsize(mdev->csums_tfm); + digest = kmalloc(digest_size, GFP_NOIO); + if (digest) { + sector_t sector = e->sector; + unsigned int size = e->size; + drbd_csum_ee(mdev, mdev->csums_tfm, e, digest); + /* Free e and pages before send. + * In case we block on congestion, we could otherwise run into + * some distributed deadlock, if the other side blocks on + * congestion as well, because our receiver blocks in + * drbd_pp_alloc due to pp_in_use > max_buffers. */ + drbd_free_ee(mdev, e); + e = NULL; + inc_rs_pending(mdev); + ok = drbd_send_drequest_csum(mdev, sector, size, + digest, digest_size, + P_CSUM_RS_REQUEST); + kfree(digest); + } else { + dev_err(DEV, "kmalloc() of digest failed.\n"); + ok = 0; + } + +out: + if (e) + drbd_free_ee(mdev, e); + + if (unlikely(!ok)) + dev_err(DEV, "drbd_send_drequest(..., csum) failed\n"); + return ok; +} + +#define GFP_TRY (__GFP_HIGHMEM | __GFP_NOWARN) + +static int read_for_csum(struct drbd_conf *mdev, sector_t sector, int size) +{ + struct drbd_epoch_entry *e; + + if (!get_ldev(mdev)) + return -EIO; + + if (drbd_rs_should_slow_down(mdev, sector)) + goto defer; + + /* GFP_TRY, because if there is no memory available right now, this may + * be rescheduled for later. It is "only" background resync, after all. */ + e = drbd_alloc_ee(mdev, DRBD_MAGIC+0xbeef, sector, size, GFP_TRY); + if (!e) + goto defer; + + e->w.cb = w_e_send_csum; + spin_lock_irq(&mdev->req_lock); + list_add(&e->w.list, &mdev->read_ee); + spin_unlock_irq(&mdev->req_lock); + + atomic_add(size >> 9, &mdev->rs_sect_ev); + if (drbd_submit_ee(mdev, e, READ, DRBD_FAULT_RS_RD) == 0) + return 0; + + /* If it failed because of ENOMEM, retry should help. If it failed + * because bio_add_page failed (probably broken lower level driver), + * retry may or may not help. + * If it does not, you may need to force disconnect. */ + spin_lock_irq(&mdev->req_lock); + list_del(&e->w.list); + spin_unlock_irq(&mdev->req_lock); + + drbd_free_ee(mdev, e); +defer: + put_ldev(mdev); + return -EAGAIN; +} + +int w_resync_timer(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + switch (mdev->state.conn) { + case C_VERIFY_S: + w_make_ov_request(mdev, w, cancel); + break; + case C_SYNC_TARGET: + w_make_resync_request(mdev, w, cancel); + break; + } + + return 1; +} + +void resync_timer_fn(unsigned long data) +{ + struct drbd_conf *mdev = (struct drbd_conf *) data; + + if (list_empty(&mdev->resync_work.list)) + drbd_queue_work(&mdev->data.work, &mdev->resync_work); +} + +static void fifo_set(struct fifo_buffer *fb, int value) +{ + int i; + + for (i = 0; i < fb->size; i++) + fb->values[i] = value; +} + +static int fifo_push(struct fifo_buffer *fb, int value) +{ + int ov; + + ov = fb->values[fb->head_index]; + fb->values[fb->head_index++] = value; + + if (fb->head_index >= fb->size) + fb->head_index = 0; + + return ov; +} + +static void fifo_add_val(struct fifo_buffer *fb, int value) +{ + int i; + + for (i = 0; i < fb->size; i++) + fb->values[i] += value; +} + +static int drbd_rs_controller(struct drbd_conf *mdev) +{ + unsigned int sect_in; /* Number of sectors that came in since the last turn */ + unsigned int want; /* The number of sectors we want in the proxy */ + int req_sect; /* Number of sectors to request in this turn */ + int correction; /* Number of sectors more we need in the proxy*/ + int cps; /* correction per invocation of drbd_rs_controller() */ + int steps; /* Number of time steps to plan ahead */ + int curr_corr; + int max_sect; + + sect_in = atomic_xchg(&mdev->rs_sect_in, 0); /* Number of sectors that came in */ + mdev->rs_in_flight -= sect_in; + + spin_lock(&mdev->peer_seq_lock); /* get an atomic view on mdev->rs_plan_s */ + + steps = mdev->rs_plan_s.size; /* (mdev->sync_conf.c_plan_ahead * 10 * SLEEP_TIME) / HZ; */ + + if (mdev->rs_in_flight + sect_in == 0) { /* At start of resync */ + want = ((mdev->sync_conf.rate * 2 * SLEEP_TIME) / HZ) * steps; + } else { /* normal path */ + want = mdev->sync_conf.c_fill_target ? mdev->sync_conf.c_fill_target : + sect_in * mdev->sync_conf.c_delay_target * HZ / (SLEEP_TIME * 10); + } + + correction = want - mdev->rs_in_flight - mdev->rs_planed; + + /* Plan ahead */ + cps = correction / steps; + fifo_add_val(&mdev->rs_plan_s, cps); + mdev->rs_planed += cps * steps; + + /* What we do in this step */ + curr_corr = fifo_push(&mdev->rs_plan_s, 0); + spin_unlock(&mdev->peer_seq_lock); + mdev->rs_planed -= curr_corr; + + req_sect = sect_in + curr_corr; + if (req_sect < 0) + req_sect = 0; + + max_sect = (mdev->sync_conf.c_max_rate * 2 * SLEEP_TIME) / HZ; + if (req_sect > max_sect) + req_sect = max_sect; + + /* + dev_warn(DEV, "si=%u if=%d wa=%u co=%d st=%d cps=%d pl=%d cc=%d rs=%d\n", + sect_in, mdev->rs_in_flight, want, correction, + steps, cps, mdev->rs_planed, curr_corr, req_sect); + */ + + return req_sect; +} + +static int drbd_rs_number_requests(struct drbd_conf *mdev) +{ + int number; + if (mdev->rs_plan_s.size) { /* mdev->sync_conf.c_plan_ahead */ + number = drbd_rs_controller(mdev) >> (BM_BLOCK_SHIFT - 9); + mdev->c_sync_rate = number * HZ * (BM_BLOCK_SIZE / 1024) / SLEEP_TIME; + } else { + mdev->c_sync_rate = mdev->sync_conf.rate; + number = SLEEP_TIME * mdev->c_sync_rate / ((BM_BLOCK_SIZE / 1024) * HZ); + } + + /* ignore the amount of pending requests, the resync controller should + * throttle down to incoming reply rate soon enough anyways. */ + return number; +} + +static int w_make_resync_request(struct drbd_conf *mdev, + struct drbd_work *w, int cancel) +{ + unsigned long bit; + sector_t sector; + const sector_t capacity = drbd_get_capacity(mdev->this_bdev); + int max_bio_size; + int number, rollback_i, size; + int align, queued, sndbuf; + int i = 0; + + if (unlikely(cancel)) + return 1; + + if (mdev->rs_total == 0) { + /* empty resync? */ + drbd_resync_finished(mdev); + return 1; + } + + if (!get_ldev(mdev)) { + /* Since we only need to access mdev->rsync a + get_ldev_if_state(mdev,D_FAILED) would be sufficient, but + to continue resync with a broken disk makes no sense at + all */ + dev_err(DEV, "Disk broke down during resync!\n"); + return 1; + } + + max_bio_size = queue_max_hw_sectors(mdev->rq_queue) << 9; + number = drbd_rs_number_requests(mdev); + if (number == 0) + goto requeue; + + for (i = 0; i < number; i++) { + /* Stop generating RS requests, when half of the send buffer is filled */ + mutex_lock(&mdev->data.mutex); + if (mdev->data.socket) { + queued = mdev->data.socket->sk->sk_wmem_queued; + sndbuf = mdev->data.socket->sk->sk_sndbuf; + } else { + queued = 1; + sndbuf = 0; + } + mutex_unlock(&mdev->data.mutex); + if (queued > sndbuf / 2) + goto requeue; + +next_sector: + size = BM_BLOCK_SIZE; + bit = drbd_bm_find_next(mdev, mdev->bm_resync_fo); + + if (bit == DRBD_END_OF_BITMAP) { + mdev->bm_resync_fo = drbd_bm_bits(mdev); + put_ldev(mdev); + return 1; + } + + sector = BM_BIT_TO_SECT(bit); + + if (drbd_rs_should_slow_down(mdev, sector) || + drbd_try_rs_begin_io(mdev, sector)) { + mdev->bm_resync_fo = bit; + goto requeue; + } + mdev->bm_resync_fo = bit + 1; + + if (unlikely(drbd_bm_test_bit(mdev, bit) == 0)) { + drbd_rs_complete_io(mdev, sector); + goto next_sector; + } + +#if DRBD_MAX_BIO_SIZE > BM_BLOCK_SIZE + /* try to find some adjacent bits. + * we stop if we have already the maximum req size. + * + * Additionally always align bigger requests, in order to + * be prepared for all stripe sizes of software RAIDs. + */ + align = 1; + rollback_i = i; + for (;;) { + if (size + BM_BLOCK_SIZE > max_bio_size) + break; + + /* Be always aligned */ + if (sector & ((1<<(align+3))-1)) + break; + + /* do not cross extent boundaries */ + if (((bit+1) & BM_BLOCKS_PER_BM_EXT_MASK) == 0) + break; + /* now, is it actually dirty, after all? + * caution, drbd_bm_test_bit is tri-state for some + * obscure reason; ( b == 0 ) would get the out-of-band + * only accidentally right because of the "oddly sized" + * adjustment below */ + if (drbd_bm_test_bit(mdev, bit+1) != 1) + break; + bit++; + size += BM_BLOCK_SIZE; + if ((BM_BLOCK_SIZE << align) <= size) + align++; + i++; + } + /* if we merged some, + * reset the offset to start the next drbd_bm_find_next from */ + if (size > BM_BLOCK_SIZE) + mdev->bm_resync_fo = bit + 1; +#endif + + /* adjust very last sectors, in case we are oddly sized */ + if (sector + (size>>9) > capacity) + size = (capacity-sector)<<9; + if (mdev->agreed_pro_version >= 89 && mdev->csums_tfm) { + switch (read_for_csum(mdev, sector, size)) { + case -EIO: /* Disk failure */ + put_ldev(mdev); + return 0; + case -EAGAIN: /* allocation failed, or ldev busy */ + drbd_rs_complete_io(mdev, sector); + mdev->bm_resync_fo = BM_SECT_TO_BIT(sector); + i = rollback_i; + goto requeue; + case 0: + /* everything ok */ + break; + default: + BUG(); + } + } else { + inc_rs_pending(mdev); + if (!drbd_send_drequest(mdev, P_RS_DATA_REQUEST, + sector, size, ID_SYNCER)) { + dev_err(DEV, "drbd_send_drequest() failed, aborting...\n"); + dec_rs_pending(mdev); + put_ldev(mdev); + return 0; + } + } + } + + if (mdev->bm_resync_fo >= drbd_bm_bits(mdev)) { + /* last syncer _request_ was sent, + * but the P_RS_DATA_REPLY not yet received. sync will end (and + * next sync group will resume), as soon as we receive the last + * resync data block, and the last bit is cleared. + * until then resync "work" is "inactive" ... + */ + put_ldev(mdev); + return 1; + } + + requeue: + mdev->rs_in_flight += (i << (BM_BLOCK_SHIFT - 9)); + mod_timer(&mdev->resync_timer, jiffies + SLEEP_TIME); + put_ldev(mdev); + return 1; +} + +static int w_make_ov_request(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + int number, i, size; + sector_t sector; + const sector_t capacity = drbd_get_capacity(mdev->this_bdev); + + if (unlikely(cancel)) + return 1; + + number = drbd_rs_number_requests(mdev); + + sector = mdev->ov_position; + for (i = 0; i < number; i++) { + if (sector >= capacity) { + return 1; + } + + size = BM_BLOCK_SIZE; + + if (drbd_rs_should_slow_down(mdev, sector) || + drbd_try_rs_begin_io(mdev, sector)) { + mdev->ov_position = sector; + goto requeue; + } + + if (sector + (size>>9) > capacity) + size = (capacity-sector)<<9; + + inc_rs_pending(mdev); + if (!drbd_send_ov_request(mdev, sector, size)) { + dec_rs_pending(mdev); + return 0; + } + sector += BM_SECT_PER_BIT; + } + mdev->ov_position = sector; + + requeue: + mdev->rs_in_flight += (i << (BM_BLOCK_SHIFT - 9)); + mod_timer(&mdev->resync_timer, jiffies + SLEEP_TIME); + return 1; +} + + +void start_resync_timer_fn(unsigned long data) +{ + struct drbd_conf *mdev = (struct drbd_conf *) data; + + drbd_queue_work(&mdev->data.work, &mdev->start_resync_work); +} + +int w_start_resync(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + if (atomic_read(&mdev->unacked_cnt) || atomic_read(&mdev->rs_pending_cnt)) { + dev_warn(DEV, "w_start_resync later...\n"); + mdev->start_resync_timer.expires = jiffies + HZ/10; + add_timer(&mdev->start_resync_timer); + return 1; + } + + drbd_start_resync(mdev, C_SYNC_SOURCE); + clear_bit(AHEAD_TO_SYNC_SOURCE, &mdev->current_epoch->flags); + return 1; +} + +int w_ov_finished(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + kfree(w); + ov_oos_print(mdev); + drbd_resync_finished(mdev); + + return 1; +} + +static int w_resync_finished(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + kfree(w); + + drbd_resync_finished(mdev); + + return 1; +} + +static void ping_peer(struct drbd_conf *mdev) +{ + clear_bit(GOT_PING_ACK, &mdev->flags); + request_ping(mdev); + wait_event(mdev->misc_wait, + test_bit(GOT_PING_ACK, &mdev->flags) || mdev->state.conn < C_CONNECTED); +} + +int drbd_resync_finished(struct drbd_conf *mdev) +{ + unsigned long db, dt, dbdt; + unsigned long n_oos; + union drbd_state os, ns; + struct drbd_work *w; + char *khelper_cmd = NULL; + int verify_done = 0; + + /* Remove all elements from the resync LRU. Since future actions + * might set bits in the (main) bitmap, then the entries in the + * resync LRU would be wrong. */ + if (drbd_rs_del_all(mdev)) { + /* In case this is not possible now, most probably because + * there are P_RS_DATA_REPLY Packets lingering on the worker's + * queue (or even the read operations for those packets + * is not finished by now). Retry in 100ms. */ + + schedule_timeout_interruptible(HZ / 10); + w = kmalloc(sizeof(struct drbd_work), GFP_ATOMIC); + if (w) { + w->cb = w_resync_finished; + drbd_queue_work(&mdev->data.work, w); + return 1; + } + dev_err(DEV, "Warn failed to drbd_rs_del_all() and to kmalloc(w).\n"); + } + + dt = (jiffies - mdev->rs_start - mdev->rs_paused) / HZ; + if (dt <= 0) + dt = 1; + db = mdev->rs_total; + dbdt = Bit2KB(db/dt); + mdev->rs_paused /= HZ; + + if (!get_ldev(mdev)) + goto out; + + ping_peer(mdev); + + spin_lock_irq(&mdev->req_lock); + os = mdev->state; + + verify_done = (os.conn == C_VERIFY_S || os.conn == C_VERIFY_T); + + /* This protects us against multiple calls (that can happen in the presence + of application IO), and against connectivity loss just before we arrive here. */ + if (os.conn <= C_CONNECTED) + goto out_unlock; + + ns = os; + ns.conn = C_CONNECTED; + + dev_info(DEV, "%s done (total %lu sec; paused %lu sec; %lu K/sec)\n", + verify_done ? "Online verify " : "Resync", + dt + mdev->rs_paused, mdev->rs_paused, dbdt); + + n_oos = drbd_bm_total_weight(mdev); + + if (os.conn == C_VERIFY_S || os.conn == C_VERIFY_T) { + if (n_oos) { + dev_alert(DEV, "Online verify found %lu %dk block out of sync!\n", + n_oos, Bit2KB(1)); + khelper_cmd = "out-of-sync"; + } + } else { + D_ASSERT((n_oos - mdev->rs_failed) == 0); + + if (os.conn == C_SYNC_TARGET || os.conn == C_PAUSED_SYNC_T) + khelper_cmd = "after-resync-target"; + + if (mdev->csums_tfm && mdev->rs_total) { + const unsigned long s = mdev->rs_same_csum; + const unsigned long t = mdev->rs_total; + const int ratio = + (t == 0) ? 0 : + (t < 100000) ? ((s*100)/t) : (s/(t/100)); + dev_info(DEV, "%u %% had equal checksums, eliminated: %luK; " + "transferred %luK total %luK\n", + ratio, + Bit2KB(mdev->rs_same_csum), + Bit2KB(mdev->rs_total - mdev->rs_same_csum), + Bit2KB(mdev->rs_total)); + } + } + + if (mdev->rs_failed) { + dev_info(DEV, " %lu failed blocks\n", mdev->rs_failed); + + if (os.conn == C_SYNC_TARGET || os.conn == C_PAUSED_SYNC_T) { + ns.disk = D_INCONSISTENT; + ns.pdsk = D_UP_TO_DATE; + } else { + ns.disk = D_UP_TO_DATE; + ns.pdsk = D_INCONSISTENT; + } + } else { + ns.disk = D_UP_TO_DATE; + ns.pdsk = D_UP_TO_DATE; + + if (os.conn == C_SYNC_TARGET || os.conn == C_PAUSED_SYNC_T) { + if (mdev->p_uuid) { + int i; + for (i = UI_BITMAP ; i <= UI_HISTORY_END ; i++) + _drbd_uuid_set(mdev, i, mdev->p_uuid[i]); + drbd_uuid_set(mdev, UI_BITMAP, mdev->ldev->md.uuid[UI_CURRENT]); + _drbd_uuid_set(mdev, UI_CURRENT, mdev->p_uuid[UI_CURRENT]); + } else { + dev_err(DEV, "mdev->p_uuid is NULL! BUG\n"); + } + } + + if (!(os.conn == C_VERIFY_S || os.conn == C_VERIFY_T)) { + /* for verify runs, we don't update uuids here, + * so there would be nothing to report. */ + drbd_uuid_set_bm(mdev, 0UL); + drbd_print_uuids(mdev, "updated UUIDs"); + if (mdev->p_uuid) { + /* Now the two UUID sets are equal, update what we + * know of the peer. */ + int i; + for (i = UI_CURRENT ; i <= UI_HISTORY_END ; i++) + mdev->p_uuid[i] = mdev->ldev->md.uuid[i]; + } + } + } + + _drbd_set_state(mdev, ns, CS_VERBOSE, NULL); +out_unlock: + spin_unlock_irq(&mdev->req_lock); + put_ldev(mdev); +out: + mdev->rs_total = 0; + mdev->rs_failed = 0; + mdev->rs_paused = 0; + if (verify_done) + mdev->ov_start_sector = 0; + + drbd_md_sync(mdev); + + if (khelper_cmd) + drbd_khelper(mdev, khelper_cmd); + + return 1; +} + +/* helper */ +static void move_to_net_ee_or_free(struct drbd_conf *mdev, struct drbd_epoch_entry *e) +{ + if (drbd_ee_has_active_page(e)) { + /* This might happen if sendpage() has not finished */ + int i = (e->size + PAGE_SIZE -1) >> PAGE_SHIFT; + atomic_add(i, &mdev->pp_in_use_by_net); + atomic_sub(i, &mdev->pp_in_use); + spin_lock_irq(&mdev->req_lock); + list_add_tail(&e->w.list, &mdev->net_ee); + spin_unlock_irq(&mdev->req_lock); + wake_up(&drbd_pp_wait); + } else + drbd_free_ee(mdev, e); +} + +/** + * w_e_end_data_req() - Worker callback, to send a P_DATA_REPLY packet in response to a P_DATA_REQUEST + * @mdev: DRBD device. + * @w: work object. + * @cancel: The connection will be closed anyways + */ +int w_e_end_data_req(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_epoch_entry *e = container_of(w, struct drbd_epoch_entry, w); + int ok; + + if (unlikely(cancel)) { + drbd_free_ee(mdev, e); + dec_unacked(mdev); + return 1; + } + + if (likely((e->flags & EE_WAS_ERROR) == 0)) { + ok = drbd_send_block(mdev, P_DATA_REPLY, e); + } else { + if (__ratelimit(&drbd_ratelimit_state)) + dev_err(DEV, "Sending NegDReply. sector=%llus.\n", + (unsigned long long)e->sector); + + ok = drbd_send_ack(mdev, P_NEG_DREPLY, e); + } + + dec_unacked(mdev); + + move_to_net_ee_or_free(mdev, e); + + if (unlikely(!ok)) + dev_err(DEV, "drbd_send_block() failed\n"); + return ok; +} + +/** + * w_e_end_rsdata_req() - Worker callback to send a P_RS_DATA_REPLY packet in response to a P_RS_DATA_REQUESTRS + * @mdev: DRBD device. + * @w: work object. + * @cancel: The connection will be closed anyways + */ +int w_e_end_rsdata_req(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_epoch_entry *e = container_of(w, struct drbd_epoch_entry, w); + int ok; + + if (unlikely(cancel)) { + drbd_free_ee(mdev, e); + dec_unacked(mdev); + return 1; + } + + if (get_ldev_if_state(mdev, D_FAILED)) { + drbd_rs_complete_io(mdev, e->sector); + put_ldev(mdev); + } + + if (mdev->state.conn == C_AHEAD) { + ok = drbd_send_ack(mdev, P_RS_CANCEL, e); + } else if (likely((e->flags & EE_WAS_ERROR) == 0)) { + if (likely(mdev->state.pdsk >= D_INCONSISTENT)) { + inc_rs_pending(mdev); + ok = drbd_send_block(mdev, P_RS_DATA_REPLY, e); + } else { + if (__ratelimit(&drbd_ratelimit_state)) + dev_err(DEV, "Not sending RSDataReply, " + "partner DISKLESS!\n"); + ok = 1; + } + } else { + if (__ratelimit(&drbd_ratelimit_state)) + dev_err(DEV, "Sending NegRSDReply. sector %llus.\n", + (unsigned long long)e->sector); + + ok = drbd_send_ack(mdev, P_NEG_RS_DREPLY, e); + + /* update resync data with failure */ + drbd_rs_failed_io(mdev, e->sector, e->size); + } + + dec_unacked(mdev); + + move_to_net_ee_or_free(mdev, e); + + if (unlikely(!ok)) + dev_err(DEV, "drbd_send_block() failed\n"); + return ok; +} + +int w_e_end_csum_rs_req(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_epoch_entry *e = container_of(w, struct drbd_epoch_entry, w); + struct digest_info *di; + int digest_size; + void *digest = NULL; + int ok, eq = 0; + + if (unlikely(cancel)) { + drbd_free_ee(mdev, e); + dec_unacked(mdev); + return 1; + } + + if (get_ldev(mdev)) { + drbd_rs_complete_io(mdev, e->sector); + put_ldev(mdev); + } + + di = e->digest; + + if (likely((e->flags & EE_WAS_ERROR) == 0)) { + /* quick hack to try to avoid a race against reconfiguration. + * a real fix would be much more involved, + * introducing more locking mechanisms */ + if (mdev->csums_tfm) { + digest_size = crypto_hash_digestsize(mdev->csums_tfm); + D_ASSERT(digest_size == di->digest_size); + digest = kmalloc(digest_size, GFP_NOIO); + } + if (digest) { + drbd_csum_ee(mdev, mdev->csums_tfm, e, digest); + eq = !memcmp(digest, di->digest, digest_size); + kfree(digest); + } + + if (eq) { + drbd_set_in_sync(mdev, e->sector, e->size); + /* rs_same_csums unit is BM_BLOCK_SIZE */ + mdev->rs_same_csum += e->size >> BM_BLOCK_SHIFT; + ok = drbd_send_ack(mdev, P_RS_IS_IN_SYNC, e); + } else { + inc_rs_pending(mdev); + e->block_id = ID_SYNCER; /* By setting block_id, digest pointer becomes invalid! */ + e->flags &= ~EE_HAS_DIGEST; /* This e no longer has a digest pointer */ + kfree(di); + ok = drbd_send_block(mdev, P_RS_DATA_REPLY, e); + } + } else { + ok = drbd_send_ack(mdev, P_NEG_RS_DREPLY, e); + if (__ratelimit(&drbd_ratelimit_state)) + dev_err(DEV, "Sending NegDReply. I guess it gets messy.\n"); + } + + dec_unacked(mdev); + move_to_net_ee_or_free(mdev, e); + + if (unlikely(!ok)) + dev_err(DEV, "drbd_send_block/ack() failed\n"); + return ok; +} + +/* TODO merge common code with w_e_send_csum */ +int w_e_end_ov_req(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_epoch_entry *e = container_of(w, struct drbd_epoch_entry, w); + sector_t sector = e->sector; + unsigned int size = e->size; + int digest_size; + void *digest; + int ok = 1; + + if (unlikely(cancel)) + goto out; + + digest_size = crypto_hash_digestsize(mdev->verify_tfm); + digest = kmalloc(digest_size, GFP_NOIO); + if (!digest) { + ok = 0; /* terminate the connection in case the allocation failed */ + goto out; + } + + if (likely(!(e->flags & EE_WAS_ERROR))) + drbd_csum_ee(mdev, mdev->verify_tfm, e, digest); + else + memset(digest, 0, digest_size); + + /* Free e and pages before send. + * In case we block on congestion, we could otherwise run into + * some distributed deadlock, if the other side blocks on + * congestion as well, because our receiver blocks in + * drbd_pp_alloc due to pp_in_use > max_buffers. */ + drbd_free_ee(mdev, e); + e = NULL; + inc_rs_pending(mdev); + ok = drbd_send_drequest_csum(mdev, sector, size, + digest, digest_size, + P_OV_REPLY); + if (!ok) + dec_rs_pending(mdev); + kfree(digest); + +out: + if (e) + drbd_free_ee(mdev, e); + dec_unacked(mdev); + return ok; +} + +void drbd_ov_oos_found(struct drbd_conf *mdev, sector_t sector, int size) +{ + if (mdev->ov_last_oos_start + mdev->ov_last_oos_size == sector) { + mdev->ov_last_oos_size += size>>9; + } else { + mdev->ov_last_oos_start = sector; + mdev->ov_last_oos_size = size>>9; + } + drbd_set_out_of_sync(mdev, sector, size); +} + +int w_e_end_ov_reply(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_epoch_entry *e = container_of(w, struct drbd_epoch_entry, w); + struct digest_info *di; + void *digest; + sector_t sector = e->sector; + unsigned int size = e->size; + int digest_size; + int ok, eq = 0; + + if (unlikely(cancel)) { + drbd_free_ee(mdev, e); + dec_unacked(mdev); + return 1; + } + + /* after "cancel", because after drbd_disconnect/drbd_rs_cancel_all + * the resync lru has been cleaned up already */ + if (get_ldev(mdev)) { + drbd_rs_complete_io(mdev, e->sector); + put_ldev(mdev); + } + + di = e->digest; + + if (likely((e->flags & EE_WAS_ERROR) == 0)) { + digest_size = crypto_hash_digestsize(mdev->verify_tfm); + digest = kmalloc(digest_size, GFP_NOIO); + if (digest) { + drbd_csum_ee(mdev, mdev->verify_tfm, e, digest); + + D_ASSERT(digest_size == di->digest_size); + eq = !memcmp(digest, di->digest, digest_size); + kfree(digest); + } + } + + /* Free e and pages before send. + * In case we block on congestion, we could otherwise run into + * some distributed deadlock, if the other side blocks on + * congestion as well, because our receiver blocks in + * drbd_pp_alloc due to pp_in_use > max_buffers. */ + drbd_free_ee(mdev, e); + if (!eq) + drbd_ov_oos_found(mdev, sector, size); + else + ov_oos_print(mdev); + + ok = drbd_send_ack_ex(mdev, P_OV_RESULT, sector, size, + eq ? ID_IN_SYNC : ID_OUT_OF_SYNC); + + dec_unacked(mdev); + + --mdev->ov_left; + + /* let's advance progress step marks only for every other megabyte */ + if ((mdev->ov_left & 0x200) == 0x200) + drbd_advance_rs_marks(mdev, mdev->ov_left); + + if (mdev->ov_left == 0) { + ov_oos_print(mdev); + drbd_resync_finished(mdev); + } + + return ok; +} + +int w_prev_work_done(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_wq_barrier *b = container_of(w, struct drbd_wq_barrier, w); + complete(&b->done); + return 1; +} + +int w_send_barrier(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_tl_epoch *b = container_of(w, struct drbd_tl_epoch, w); + struct p_barrier *p = &mdev->data.sbuf.barrier; + int ok = 1; + + /* really avoid racing with tl_clear. w.cb may have been referenced + * just before it was reassigned and re-queued, so double check that. + * actually, this race was harmless, since we only try to send the + * barrier packet here, and otherwise do nothing with the object. + * but compare with the head of w_clear_epoch */ + spin_lock_irq(&mdev->req_lock); + if (w->cb != w_send_barrier || mdev->state.conn < C_CONNECTED) + cancel = 1; + spin_unlock_irq(&mdev->req_lock); + if (cancel) + return 1; + + if (!drbd_get_data_sock(mdev)) + return 0; + p->barrier = b->br_number; + /* inc_ap_pending was done where this was queued. + * dec_ap_pending will be done in got_BarrierAck + * or (on connection loss) in w_clear_epoch. */ + ok = _drbd_send_cmd(mdev, mdev->data.socket, P_BARRIER, + (struct p_header80 *)p, sizeof(*p), 0); + drbd_put_data_sock(mdev); + + return ok; +} + +int w_send_write_hint(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + if (cancel) + return 1; + return drbd_send_short_cmd(mdev, P_UNPLUG_REMOTE); +} + +int w_send_oos(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_request *req = container_of(w, struct drbd_request, w); + int ok; + + if (unlikely(cancel)) { + req_mod(req, send_canceled); + return 1; + } + + ok = drbd_send_oos(mdev, req); + req_mod(req, oos_handed_to_network); + + return ok; +} + +/** + * w_send_dblock() - Worker callback to send a P_DATA packet in order to mirror a write request + * @mdev: DRBD device. + * @w: work object. + * @cancel: The connection will be closed anyways + */ +int w_send_dblock(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_request *req = container_of(w, struct drbd_request, w); + int ok; + + if (unlikely(cancel)) { + req_mod(req, send_canceled); + return 1; + } + + ok = drbd_send_dblock(mdev, req); + req_mod(req, ok ? handed_over_to_network : send_failed); + + return ok; +} + +/** + * w_send_read_req() - Worker callback to send a read request (P_DATA_REQUEST) packet + * @mdev: DRBD device. + * @w: work object. + * @cancel: The connection will be closed anyways + */ +int w_send_read_req(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_request *req = container_of(w, struct drbd_request, w); + int ok; + + if (unlikely(cancel)) { + req_mod(req, send_canceled); + return 1; + } + + ok = drbd_send_drequest(mdev, P_DATA_REQUEST, req->sector, req->size, + (unsigned long)req); + + if (!ok) { + /* ?? we set C_TIMEOUT or C_BROKEN_PIPE in drbd_send(); + * so this is probably redundant */ + if (mdev->state.conn >= C_CONNECTED) + drbd_force_state(mdev, NS(conn, C_NETWORK_FAILURE)); + } + req_mod(req, ok ? handed_over_to_network : send_failed); + + return ok; +} + +int w_restart_disk_io(struct drbd_conf *mdev, struct drbd_work *w, int cancel) +{ + struct drbd_request *req = container_of(w, struct drbd_request, w); + + if (bio_data_dir(req->master_bio) == WRITE && req->rq_state & RQ_IN_ACT_LOG) + drbd_al_begin_io(mdev, req->sector); + /* Calling drbd_al_begin_io() out of the worker might deadlocks + theoretically. Practically it can not deadlock, since this is + only used when unfreezing IOs. All the extents of the requests + that made it into the TL are already active */ + + drbd_req_make_private_bio(req, req->master_bio); + req->private_bio->bi_bdev = mdev->ldev->backing_bdev; + generic_make_request(req->private_bio); + + return 1; +} + +static int _drbd_may_sync_now(struct drbd_conf *mdev) +{ + struct drbd_conf *odev = mdev; + + while (1) { + if (odev->sync_conf.after == -1) + return 1; + odev = minor_to_mdev(odev->sync_conf.after); + ERR_IF(!odev) return 1; + if ((odev->state.conn >= C_SYNC_SOURCE && + odev->state.conn <= C_PAUSED_SYNC_T) || + odev->state.aftr_isp || odev->state.peer_isp || + odev->state.user_isp) + return 0; + } +} + +/** + * _drbd_pause_after() - Pause resync on all devices that may not resync now + * @mdev: DRBD device. + * + * Called from process context only (admin command and after_state_ch). + */ +static int _drbd_pause_after(struct drbd_conf *mdev) +{ + struct drbd_conf *odev; + int i, rv = 0; + + for (i = 0; i < minor_count; i++) { + odev = minor_to_mdev(i); + if (!odev) + continue; + if (odev->state.conn == C_STANDALONE && odev->state.disk == D_DISKLESS) + continue; + if (!_drbd_may_sync_now(odev)) + rv |= (__drbd_set_state(_NS(odev, aftr_isp, 1), CS_HARD, NULL) + != SS_NOTHING_TO_DO); + } + + return rv; +} + +/** + * _drbd_resume_next() - Resume resync on all devices that may resync now + * @mdev: DRBD device. + * + * Called from process context only (admin command and worker). + */ +static int _drbd_resume_next(struct drbd_conf *mdev) +{ + struct drbd_conf *odev; + int i, rv = 0; + + for (i = 0; i < minor_count; i++) { + odev = minor_to_mdev(i); + if (!odev) + continue; + if (odev->state.conn == C_STANDALONE && odev->state.disk == D_DISKLESS) + continue; + if (odev->state.aftr_isp) { + if (_drbd_may_sync_now(odev)) + rv |= (__drbd_set_state(_NS(odev, aftr_isp, 0), + CS_HARD, NULL) + != SS_NOTHING_TO_DO) ; + } + } + return rv; +} + +void resume_next_sg(struct drbd_conf *mdev) +{ + write_lock_irq(&global_state_lock); + _drbd_resume_next(mdev); + write_unlock_irq(&global_state_lock); +} + +void suspend_other_sg(struct drbd_conf *mdev) +{ + write_lock_irq(&global_state_lock); + _drbd_pause_after(mdev); + write_unlock_irq(&global_state_lock); +} + +static int sync_after_error(struct drbd_conf *mdev, int o_minor) +{ + struct drbd_conf *odev; + + if (o_minor == -1) + return NO_ERROR; + if (o_minor < -1 || minor_to_mdev(o_minor) == NULL) + return ERR_SYNC_AFTER; + + /* check for loops */ + odev = minor_to_mdev(o_minor); + while (1) { + if (odev == mdev) + return ERR_SYNC_AFTER_CYCLE; + + /* dependency chain ends here, no cycles. */ + if (odev->sync_conf.after == -1) + return NO_ERROR; + + /* follow the dependency chain */ + odev = minor_to_mdev(odev->sync_conf.after); + } +} + +int drbd_alter_sa(struct drbd_conf *mdev, int na) +{ + int changes; + int retcode; + + write_lock_irq(&global_state_lock); + retcode = sync_after_error(mdev, na); + if (retcode == NO_ERROR) { + mdev->sync_conf.after = na; + do { + changes = _drbd_pause_after(mdev); + changes |= _drbd_resume_next(mdev); + } while (changes); + } + write_unlock_irq(&global_state_lock); + return retcode; +} + +void drbd_rs_controller_reset(struct drbd_conf *mdev) +{ + atomic_set(&mdev->rs_sect_in, 0); + atomic_set(&mdev->rs_sect_ev, 0); + mdev->rs_in_flight = 0; + mdev->rs_planed = 0; + spin_lock(&mdev->peer_seq_lock); + fifo_set(&mdev->rs_plan_s, 0); + spin_unlock(&mdev->peer_seq_lock); +} + +/** + * drbd_start_resync() - Start the resync process + * @mdev: DRBD device. + * @side: Either C_SYNC_SOURCE or C_SYNC_TARGET + * + * This function might bring you directly into one of the + * C_PAUSED_SYNC_* states. + */ +void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side) +{ + union drbd_state ns; + int r; + + if (mdev->state.conn >= C_SYNC_SOURCE && mdev->state.conn < C_AHEAD) { + dev_err(DEV, "Resync already running!\n"); + return; + } + + if (mdev->state.conn < C_AHEAD) { + /* In case a previous resync run was aborted by an IO error/detach on the peer. */ + drbd_rs_cancel_all(mdev); + /* This should be done when we abort the resync. We definitely do not + want to have this for connections going back and forth between + Ahead/Behind and SyncSource/SyncTarget */ + } + + if (side == C_SYNC_TARGET) { + /* Since application IO was locked out during C_WF_BITMAP_T and + C_WF_SYNC_UUID we are still unmodified. Before going to C_SYNC_TARGET + we check that we might make the data inconsistent. */ + r = drbd_khelper(mdev, "before-resync-target"); + r = (r >> 8) & 0xff; + if (r > 0) { + dev_info(DEV, "before-resync-target handler returned %d, " + "dropping connection.\n", r); + drbd_force_state(mdev, NS(conn, C_DISCONNECTING)); + return; + } + } else /* C_SYNC_SOURCE */ { + r = drbd_khelper(mdev, "before-resync-source"); + r = (r >> 8) & 0xff; + if (r > 0) { + if (r == 3) { + dev_info(DEV, "before-resync-source handler returned %d, " + "ignoring. Old userland tools?", r); + } else { + dev_info(DEV, "before-resync-source handler returned %d, " + "dropping connection.\n", r); + drbd_force_state(mdev, NS(conn, C_DISCONNECTING)); + return; + } + } + } + + drbd_state_lock(mdev); + + if (!get_ldev_if_state(mdev, D_NEGOTIATING)) { + drbd_state_unlock(mdev); + return; + } + + write_lock_irq(&global_state_lock); + ns = mdev->state; + + ns.aftr_isp = !_drbd_may_sync_now(mdev); + + ns.conn = side; + + if (side == C_SYNC_TARGET) + ns.disk = D_INCONSISTENT; + else /* side == C_SYNC_SOURCE */ + ns.pdsk = D_INCONSISTENT; + + r = __drbd_set_state(mdev, ns, CS_VERBOSE, NULL); + ns = mdev->state; + + if (ns.conn < C_CONNECTED) + r = SS_UNKNOWN_ERROR; + + if (r == SS_SUCCESS) { + unsigned long tw = drbd_bm_total_weight(mdev); + unsigned long now = jiffies; + int i; + + mdev->rs_failed = 0; + mdev->rs_paused = 0; + mdev->rs_same_csum = 0; + mdev->rs_last_events = 0; + mdev->rs_last_sect_ev = 0; + mdev->rs_total = tw; + mdev->rs_start = now; + for (i = 0; i < DRBD_SYNC_MARKS; i++) { + mdev->rs_mark_left[i] = tw; + mdev->rs_mark_time[i] = now; + } + _drbd_pause_after(mdev); + } + write_unlock_irq(&global_state_lock); + + if (r == SS_SUCCESS) { + dev_info(DEV, "Began resync as %s (will sync %lu KB [%lu bits set]).\n", + drbd_conn_str(ns.conn), + (unsigned long) mdev->rs_total << (BM_BLOCK_SHIFT-10), + (unsigned long) mdev->rs_total); + if (side == C_SYNC_TARGET) + mdev->bm_resync_fo = 0; + + /* Since protocol 96, we must serialize drbd_gen_and_send_sync_uuid + * with w_send_oos, or the sync target will get confused as to + * how much bits to resync. We cannot do that always, because for an + * empty resync and protocol < 95, we need to do it here, as we call + * drbd_resync_finished from here in that case. + * We drbd_gen_and_send_sync_uuid here for protocol < 96, + * and from after_state_ch otherwise. */ + if (side == C_SYNC_SOURCE && mdev->agreed_pro_version < 96) + drbd_gen_and_send_sync_uuid(mdev); + + if (mdev->agreed_pro_version < 95 && mdev->rs_total == 0) { + /* This still has a race (about when exactly the peers + * detect connection loss) that can lead to a full sync + * on next handshake. In 8.3.9 we fixed this with explicit + * resync-finished notifications, but the fix + * introduces a protocol change. Sleeping for some + * time longer than the ping interval + timeout on the + * SyncSource, to give the SyncTarget the chance to + * detect connection loss, then waiting for a ping + * response (implicit in drbd_resync_finished) reduces + * the race considerably, but does not solve it. */ + if (side == C_SYNC_SOURCE) + schedule_timeout_interruptible( + mdev->net_conf->ping_int * HZ + + mdev->net_conf->ping_timeo*HZ/9); + drbd_resync_finished(mdev); + } + + drbd_rs_controller_reset(mdev); + /* ns.conn may already be != mdev->state.conn, + * we may have been paused in between, or become paused until + * the timer triggers. + * No matter, that is handled in resync_timer_fn() */ + if (ns.conn == C_SYNC_TARGET) + mod_timer(&mdev->resync_timer, jiffies); + + drbd_md_sync(mdev); + } + put_ldev(mdev); + drbd_state_unlock(mdev); +} + +int drbd_worker(struct drbd_thread *thi) +{ + struct drbd_conf *mdev = thi->mdev; + struct drbd_work *w = NULL; + LIST_HEAD(work_list); + int intr = 0, i; + + sprintf(current->comm, "drbd%d_worker", mdev_to_minor(mdev)); + + while (get_t_state(thi) == Running) { + drbd_thread_current_set_cpu(mdev); + + if (down_trylock(&mdev->data.work.s)) { + mutex_lock(&mdev->data.mutex); + if (mdev->data.socket && !mdev->net_conf->no_cork) + drbd_tcp_uncork(mdev->data.socket); + mutex_unlock(&mdev->data.mutex); + + intr = down_interruptible(&mdev->data.work.s); + + mutex_lock(&mdev->data.mutex); + if (mdev->data.socket && !mdev->net_conf->no_cork) + drbd_tcp_cork(mdev->data.socket); + mutex_unlock(&mdev->data.mutex); + } + + if (intr) { + D_ASSERT(intr == -EINTR); + flush_signals(current); + ERR_IF (get_t_state(thi) == Running) + continue; + break; + } + + if (get_t_state(thi) != Running) + break; + /* With this break, we have done a down() but not consumed + the entry from the list. The cleanup code takes care of + this... */ + + w = NULL; + spin_lock_irq(&mdev->data.work.q_lock); + ERR_IF(list_empty(&mdev->data.work.q)) { + /* something terribly wrong in our logic. + * we were able to down() the semaphore, + * but the list is empty... doh. + * + * what is the best thing to do now? + * try again from scratch, restarting the receiver, + * asender, whatnot? could break even more ugly, + * e.g. when we are primary, but no good local data. + * + * I'll try to get away just starting over this loop. + */ + spin_unlock_irq(&mdev->data.work.q_lock); + continue; + } + w = list_entry(mdev->data.work.q.next, struct drbd_work, list); + list_del_init(&w->list); + spin_unlock_irq(&mdev->data.work.q_lock); + + if (!w->cb(mdev, w, mdev->state.conn < C_CONNECTED)) { + /* dev_warn(DEV, "worker: a callback failed! \n"); */ + if (mdev->state.conn >= C_CONNECTED) + drbd_force_state(mdev, + NS(conn, C_NETWORK_FAILURE)); + } + } + D_ASSERT(test_bit(DEVICE_DYING, &mdev->flags)); + D_ASSERT(test_bit(CONFIG_PENDING, &mdev->flags)); + + spin_lock_irq(&mdev->data.work.q_lock); + i = 0; + while (!list_empty(&mdev->data.work.q)) { + list_splice_init(&mdev->data.work.q, &work_list); + spin_unlock_irq(&mdev->data.work.q_lock); + + while (!list_empty(&work_list)) { + w = list_entry(work_list.next, struct drbd_work, list); + list_del_init(&w->list); + w->cb(mdev, w, 1); + i++; /* dead debugging code */ + } + + spin_lock_irq(&mdev->data.work.q_lock); + } + sema_init(&mdev->data.work.s, 0); + /* DANGEROUS race: if someone did queue his work within the spinlock, + * but up() ed outside the spinlock, we could get an up() on the + * semaphore without corresponding list entry. + * So don't do that. + */ + spin_unlock_irq(&mdev->data.work.q_lock); + + D_ASSERT(mdev->state.disk == D_DISKLESS && mdev->state.conn == C_STANDALONE); + /* _drbd_set_state only uses stop_nowait. + * wait here for the Exiting receiver. */ + drbd_thread_stop(&mdev->receiver); + drbd_mdev_cleanup(mdev); + + dev_info(DEV, "worker terminated\n"); + + clear_bit(DEVICE_DYING, &mdev->flags); + clear_bit(CONFIG_PENDING, &mdev->flags); + wake_up(&mdev->state_wait); + + return 0; +} |