X-Git-Url: https://git.stricted.de/?a=blobdiff_plain;f=drivers%2Fmd%2Fdm.c;h=745ca1f67b14a93db8e7c2802746d7963641aa7e;hb=63d94e482df769f31e8b1097f06c3a3fba7bced4;hp=930b9fc27953766e94b2ce8869f6228feb5f04b3;hpb=0dd7f883a9e21c5f2ff5e8f1cbb0e78cdc044d8a;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 930b9fc27953..745ca1f67b14 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -31,6 +31,7 @@ struct dm_io { int error; struct bio *bio; atomic_t io_count; + unsigned long start_time; }; /* @@ -55,6 +56,7 @@ union map_info *dm_get_mapinfo(struct bio *bio) */ #define DMF_BLOCK_IO 0 #define DMF_SUSPENDED 1 +#define DMF_FROZEN 2 struct mapped_device { struct rw_semaphore io_lock; @@ -97,7 +99,7 @@ struct mapped_device { * freeze/thaw support require holding onto a super block */ struct super_block *frozen_sb; - struct block_device *frozen_bdev; + struct block_device *suspended_bdev; }; #define MIN_IOS 256 @@ -243,6 +245,36 @@ static inline void free_tio(struct mapped_device *md, struct target_io *tio) mempool_free(tio, md->tio_pool); } +static void start_io_acct(struct dm_io *io) +{ + struct mapped_device *md = io->md; + + io->start_time = jiffies; + + preempt_disable(); + disk_round_stats(dm_disk(md)); + preempt_enable(); + dm_disk(md)->in_flight = atomic_inc_return(&md->pending); +} + +static int end_io_acct(struct dm_io *io) +{ + struct mapped_device *md = io->md; + struct bio *bio = io->bio; + unsigned long duration = jiffies - io->start_time; + int pending; + int rw = bio_data_dir(bio); + + preempt_disable(); + disk_round_stats(dm_disk(md)); + preempt_enable(); + dm_disk(md)->in_flight = pending = atomic_dec_return(&md->pending); + + disk_stat_add(dm_disk(md), ticks[rw], duration); + + return !pending; +} + /* * Add the bio to the list of deferred io. */ @@ -292,13 +324,13 @@ struct dm_table *dm_get_table(struct mapped_device *md) * Decrements the number of outstanding ios that a bio has been * cloned into, completing the original io if necc. */ -static inline void dec_pending(struct dm_io *io, int error) +static void dec_pending(struct dm_io *io, int error) { if (error) io->error = error; if (atomic_dec_and_test(&io->io_count)) { - if (atomic_dec_and_test(&io->md->pending)) + if (end_io_acct(io)) /* nudge anyone waiting on suspend queue */ wake_up(&io->md->wait); @@ -553,7 +585,7 @@ static void __split_bio(struct mapped_device *md, struct bio *bio) ci.sector_count = bio_sectors(bio); ci.idx = bio->bi_idx; - atomic_inc(&md->pending); + start_io_acct(ci.io); while (ci.sector_count) __clone_and_map(&ci); @@ -572,10 +604,14 @@ static void __split_bio(struct mapped_device *md, struct bio *bio) static int dm_request(request_queue_t *q, struct bio *bio) { int r; + int rw = bio_data_dir(bio); struct mapped_device *md = q->queuedata; down_read(&md->io_lock); + disk_stat_inc(dm_disk(md), ios[rw]); + disk_stat_add(dm_disk(md), sectors[rw], bio_sectors(bio)); + /* * If we're suspended we have to queue * this io for later. @@ -767,6 +803,7 @@ static struct mapped_device *alloc_dev(unsigned int minor, int persistent) md->queue->backing_dev_info.congested_fn = dm_any_congested; md->queue->backing_dev_info.congested_data = md; blk_queue_make_request(md->queue, dm_request); + blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); md->queue->unplug_fn = dm_unplug_all; md->queue->issue_flush_fn = dm_flush_all; @@ -812,10 +849,16 @@ static struct mapped_device *alloc_dev(unsigned int minor, int persistent) static void free_dev(struct mapped_device *md) { - free_minor(md->disk->first_minor); + unsigned int minor = md->disk->first_minor; + + if (md->suspended_bdev) { + thaw_bdev(md->suspended_bdev, NULL); + bdput(md->suspended_bdev); + } mempool_destroy(md->tio_pool); mempool_destroy(md->io_pool); del_gendisk(md->disk); + free_minor(minor); put_disk(md->disk); blk_put_queue(md->queue); kfree(md); @@ -836,9 +879,9 @@ static void __set_size(struct mapped_device *md, sector_t size) { set_capacity(md->disk, size); - down(&md->frozen_bdev->bd_inode->i_sem); - i_size_write(md->frozen_bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); - up(&md->frozen_bdev->bd_inode->i_sem); + mutex_lock(&md->suspended_bdev->bd_inode->i_mutex); + i_size_write(md->suspended_bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); + mutex_unlock(&md->suspended_bdev->bd_inode->i_mutex); } static int __bind(struct mapped_device *md, struct dm_table *t) @@ -902,10 +945,9 @@ int dm_create_with_minor(unsigned int minor, struct mapped_device **result) return create_aux(minor, 1, result); } -void *dm_get_mdptr(dev_t dev) +static struct mapped_device *dm_find_md(dev_t dev) { struct mapped_device *md; - void *mdptr = NULL; unsigned minor = MINOR(dev); if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) @@ -914,12 +956,32 @@ void *dm_get_mdptr(dev_t dev) down(&_minor_lock); md = idr_find(&_minor_idr, minor); - - if (md && (dm_disk(md)->first_minor == minor)) - mdptr = md->interface_ptr; + if (!md || (dm_disk(md)->first_minor != minor)) + md = NULL; up(&_minor_lock); + return md; +} + +struct mapped_device *dm_get_md(dev_t dev) +{ + struct mapped_device *md = dm_find_md(dev); + + if (md) + dm_get(md); + + return md; +} + +void *dm_get_mdptr(dev_t dev) +{ + struct mapped_device *md; + void *mdptr = NULL; + + md = dm_find_md(dev); + if (md) + mdptr = md->interface_ptr; return mdptr; } @@ -991,43 +1053,33 @@ out: */ static int lock_fs(struct mapped_device *md) { - int r = -ENOMEM; - - md->frozen_bdev = bdget_disk(md->disk, 0); - if (!md->frozen_bdev) { - DMWARN("bdget failed in lock_fs"); - goto out; - } + int r; WARN_ON(md->frozen_sb); - md->frozen_sb = freeze_bdev(md->frozen_bdev); + md->frozen_sb = freeze_bdev(md->suspended_bdev); if (IS_ERR(md->frozen_sb)) { r = PTR_ERR(md->frozen_sb); - goto out_bdput; + md->frozen_sb = NULL; + return r; } + set_bit(DMF_FROZEN, &md->flags); + /* don't bdput right now, we don't want the bdev - * to go away while it is locked. We'll bdput - * in unlock_fs + * to go away while it is locked. */ return 0; - -out_bdput: - bdput(md->frozen_bdev); - md->frozen_sb = NULL; - md->frozen_bdev = NULL; -out: - return r; } static void unlock_fs(struct mapped_device *md) { - thaw_bdev(md->frozen_bdev, md->frozen_sb); - bdput(md->frozen_bdev); + if (!test_bit(DMF_FROZEN, &md->flags)) + return; + thaw_bdev(md->suspended_bdev, md->frozen_sb); md->frozen_sb = NULL; - md->frozen_bdev = NULL; + clear_bit(DMF_FROZEN, &md->flags); } /* @@ -1037,7 +1089,7 @@ static void unlock_fs(struct mapped_device *md) * dm_bind_table, dm_suspend must be called to flush any in * flight bios and ensure that any further io gets deferred. */ -int dm_suspend(struct mapped_device *md) +int dm_suspend(struct mapped_device *md, int do_lockfs) { struct dm_table *map = NULL; DECLARE_WAITQUEUE(wait, current); @@ -1053,10 +1105,19 @@ int dm_suspend(struct mapped_device *md) /* This does not get reverted if there's an error later. */ dm_table_presuspend_targets(map); - /* Flush I/O to the device. */ - r = lock_fs(md); - if (r) + md->suspended_bdev = bdget_disk(md->disk, 0); + if (!md->suspended_bdev) { + DMWARN("bdget failed in dm_suspend"); + r = -ENOMEM; goto out; + } + + /* Flush I/O to the device. */ + if (do_lockfs) { + r = lock_fs(md); + if (r) + goto out; + } /* * First we set the BLOCK_IO flag so no more ios will be mapped. @@ -1105,6 +1166,11 @@ int dm_suspend(struct mapped_device *md) r = 0; out: + if (r && md->suspended_bdev) { + bdput(md->suspended_bdev); + md->suspended_bdev = NULL; + } + dm_table_put(map); up(&md->suspend_lock); return r; @@ -1135,6 +1201,9 @@ int dm_resume(struct mapped_device *md) unlock_fs(md); + bdput(md->suspended_bdev); + md->suspended_bdev = NULL; + clear_bit(DMF_SUSPENDED, &md->flags); dm_table_unplug_all(map);