diff options
Diffstat (limited to 'ANDROID_3.4.5/drivers/md/linear.c')
| -rw-r--r-- | ANDROID_3.4.5/drivers/md/linear.c | 369 |
1 files changed, 0 insertions, 369 deletions
diff --git a/ANDROID_3.4.5/drivers/md/linear.c b/ANDROID_3.4.5/drivers/md/linear.c deleted file mode 100644 index fa211d80..00000000 --- a/ANDROID_3.4.5/drivers/md/linear.c +++ /dev/null @@ -1,369 +0,0 @@ -/* - linear.c : Multiple Devices driver for Linux - Copyright (C) 1994-96 Marc ZYNGIER - <zyngier@ufr-info-p7.ibp.fr> or - <maz@gloups.fdn.fr> - - Linear mode management functions. - - 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. -*/ - -#include <linux/blkdev.h> -#include <linux/raid/md_u.h> -#include <linux/seq_file.h> -#include <linux/module.h> -#include <linux/slab.h> -#include "md.h" -#include "linear.h" - -/* - * find which device holds a particular offset - */ -static inline struct dev_info *which_dev(struct mddev *mddev, sector_t sector) -{ - int lo, mid, hi; - struct linear_conf *conf; - - lo = 0; - hi = mddev->raid_disks - 1; - conf = rcu_dereference(mddev->private); - - /* - * Binary Search - */ - - while (hi > lo) { - - mid = (hi + lo) / 2; - if (sector < conf->disks[mid].end_sector) - hi = mid; - else - lo = mid + 1; - } - - return conf->disks + lo; -} - -/** - * linear_mergeable_bvec -- tell bio layer if two requests can be merged - * @q: request queue - * @bvm: properties of new bio - * @biovec: the request that could be merged to it. - * - * Return amount of bytes we can take at this offset - */ -static int linear_mergeable_bvec(struct request_queue *q, - struct bvec_merge_data *bvm, - struct bio_vec *biovec) -{ - struct mddev *mddev = q->queuedata; - struct dev_info *dev0; - unsigned long maxsectors, bio_sectors = bvm->bi_size >> 9; - sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev); - int maxbytes = biovec->bv_len; - struct request_queue *subq; - - rcu_read_lock(); - dev0 = which_dev(mddev, sector); - maxsectors = dev0->end_sector - sector; - subq = bdev_get_queue(dev0->rdev->bdev); - if (subq->merge_bvec_fn) { - bvm->bi_bdev = dev0->rdev->bdev; - bvm->bi_sector -= dev0->end_sector - dev0->rdev->sectors; - maxbytes = min(maxbytes, subq->merge_bvec_fn(subq, bvm, - biovec)); - } - rcu_read_unlock(); - - if (maxsectors < bio_sectors) - maxsectors = 0; - else - maxsectors -= bio_sectors; - - if (maxsectors <= (PAGE_SIZE >> 9 ) && bio_sectors == 0) - return maxbytes; - - if (maxsectors > (maxbytes >> 9)) - return maxbytes; - else - return maxsectors << 9; -} - -static int linear_congested(void *data, int bits) -{ - struct mddev *mddev = data; - struct linear_conf *conf; - int i, ret = 0; - - if (mddev_congested(mddev, bits)) - return 1; - - rcu_read_lock(); - conf = rcu_dereference(mddev->private); - - for (i = 0; i < mddev->raid_disks && !ret ; i++) { - struct request_queue *q = bdev_get_queue(conf->disks[i].rdev->bdev); - ret |= bdi_congested(&q->backing_dev_info, bits); - } - - rcu_read_unlock(); - return ret; -} - -static sector_t linear_size(struct mddev *mddev, sector_t sectors, int raid_disks) -{ - struct linear_conf *conf; - sector_t array_sectors; - - rcu_read_lock(); - conf = rcu_dereference(mddev->private); - WARN_ONCE(sectors || raid_disks, - "%s does not support generic reshape\n", __func__); - array_sectors = conf->array_sectors; - rcu_read_unlock(); - - return array_sectors; -} - -static struct linear_conf *linear_conf(struct mddev *mddev, int raid_disks) -{ - struct linear_conf *conf; - struct md_rdev *rdev; - int i, cnt; - - conf = kzalloc (sizeof (*conf) + raid_disks*sizeof(struct dev_info), - GFP_KERNEL); - if (!conf) - return NULL; - - cnt = 0; - conf->array_sectors = 0; - - rdev_for_each(rdev, mddev) { - int j = rdev->raid_disk; - struct dev_info *disk = conf->disks + j; - sector_t sectors; - - if (j < 0 || j >= raid_disks || disk->rdev) { - printk(KERN_ERR "md/linear:%s: disk numbering problem. Aborting!\n", - mdname(mddev)); - goto out; - } - - disk->rdev = rdev; - if (mddev->chunk_sectors) { - sectors = rdev->sectors; - sector_div(sectors, mddev->chunk_sectors); - rdev->sectors = sectors * mddev->chunk_sectors; - } - - disk_stack_limits(mddev->gendisk, rdev->bdev, - rdev->data_offset << 9); - - conf->array_sectors += rdev->sectors; - cnt++; - - } - if (cnt != raid_disks) { - printk(KERN_ERR "md/linear:%s: not enough drives present. Aborting!\n", - mdname(mddev)); - goto out; - } - - /* - * Here we calculate the device offsets. - */ - conf->disks[0].end_sector = conf->disks[0].rdev->sectors; - - for (i = 1; i < raid_disks; i++) - conf->disks[i].end_sector = - conf->disks[i-1].end_sector + - conf->disks[i].rdev->sectors; - - return conf; - -out: - kfree(conf); - return NULL; -} - -static int linear_run (struct mddev *mddev) -{ - struct linear_conf *conf; - int ret; - - if (md_check_no_bitmap(mddev)) - return -EINVAL; - conf = linear_conf(mddev, mddev->raid_disks); - - if (!conf) - return 1; - mddev->private = conf; - md_set_array_sectors(mddev, linear_size(mddev, 0, 0)); - - blk_queue_merge_bvec(mddev->queue, linear_mergeable_bvec); - mddev->queue->backing_dev_info.congested_fn = linear_congested; - mddev->queue->backing_dev_info.congested_data = mddev; - - ret = md_integrity_register(mddev); - if (ret) { - kfree(conf); - mddev->private = NULL; - } - return ret; -} - -static int linear_add(struct mddev *mddev, struct md_rdev *rdev) -{ - /* Adding a drive to a linear array allows the array to grow. - * It is permitted if the new drive has a matching superblock - * already on it, with raid_disk equal to raid_disks. - * It is achieved by creating a new linear_private_data structure - * and swapping it in in-place of the current one. - * The current one is never freed until the array is stopped. - * This avoids races. - */ - struct linear_conf *newconf, *oldconf; - - if (rdev->saved_raid_disk != mddev->raid_disks) - return -EINVAL; - - rdev->raid_disk = rdev->saved_raid_disk; - rdev->saved_raid_disk = -1; - - newconf = linear_conf(mddev,mddev->raid_disks+1); - - if (!newconf) - return -ENOMEM; - - oldconf = rcu_dereference(mddev->private); - mddev->raid_disks++; - rcu_assign_pointer(mddev->private, newconf); - md_set_array_sectors(mddev, linear_size(mddev, 0, 0)); - set_capacity(mddev->gendisk, mddev->array_sectors); - revalidate_disk(mddev->gendisk); - kfree_rcu(oldconf, rcu); - return 0; -} - -static int linear_stop (struct mddev *mddev) -{ - struct linear_conf *conf = mddev->private; - - /* - * We do not require rcu protection here since - * we hold reconfig_mutex for both linear_add and - * linear_stop, so they cannot race. - * We should make sure any old 'conf's are properly - * freed though. - */ - rcu_barrier(); - blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ - kfree(conf); - mddev->private = NULL; - - return 0; -} - -static void linear_make_request(struct mddev *mddev, struct bio *bio) -{ - struct dev_info *tmp_dev; - sector_t start_sector; - - if (unlikely(bio->bi_rw & REQ_FLUSH)) { - md_flush_request(mddev, bio); - return; - } - - rcu_read_lock(); - tmp_dev = which_dev(mddev, bio->bi_sector); - start_sector = tmp_dev->end_sector - tmp_dev->rdev->sectors; - - - if (unlikely(bio->bi_sector >= (tmp_dev->end_sector) - || (bio->bi_sector < start_sector))) { - char b[BDEVNAME_SIZE]; - - printk(KERN_ERR - "md/linear:%s: make_request: Sector %llu out of bounds on " - "dev %s: %llu sectors, offset %llu\n", - mdname(mddev), - (unsigned long long)bio->bi_sector, - bdevname(tmp_dev->rdev->bdev, b), - (unsigned long long)tmp_dev->rdev->sectors, - (unsigned long long)start_sector); - rcu_read_unlock(); - bio_io_error(bio); - return; - } - if (unlikely(bio->bi_sector + (bio->bi_size >> 9) > - tmp_dev->end_sector)) { - /* This bio crosses a device boundary, so we have to - * split it. - */ - struct bio_pair *bp; - sector_t end_sector = tmp_dev->end_sector; - - rcu_read_unlock(); - - bp = bio_split(bio, end_sector - bio->bi_sector); - - linear_make_request(mddev, &bp->bio1); - linear_make_request(mddev, &bp->bio2); - bio_pair_release(bp); - return; - } - - bio->bi_bdev = tmp_dev->rdev->bdev; - bio->bi_sector = bio->bi_sector - start_sector - + tmp_dev->rdev->data_offset; - rcu_read_unlock(); - generic_make_request(bio); -} - -static void linear_status (struct seq_file *seq, struct mddev *mddev) -{ - - seq_printf(seq, " %dk rounding", mddev->chunk_sectors / 2); -} - - -static struct md_personality linear_personality = -{ - .name = "linear", - .level = LEVEL_LINEAR, - .owner = THIS_MODULE, - .make_request = linear_make_request, - .run = linear_run, - .stop = linear_stop, - .status = linear_status, - .hot_add_disk = linear_add, - .size = linear_size, -}; - -static int __init linear_init (void) -{ - return register_md_personality (&linear_personality); -} - -static void linear_exit (void) -{ - unregister_md_personality (&linear_personality); -} - - -module_init(linear_init); -module_exit(linear_exit); -MODULE_LICENSE("GPL"); -MODULE_DESCRIPTION("Linear device concatenation personality for MD"); -MODULE_ALIAS("md-personality-1"); /* LINEAR - deprecated*/ -MODULE_ALIAS("md-linear"); -MODULE_ALIAS("md-level--1"); |