From b17446df2ebcaf32889376d90f4b9b2baebb2db6 Mon Sep 17 00:00:00 2001 From: Joe Thornber Date: Fri, 10 May 2013 14:37:18 +0100 Subject: [PATCH] dm thin: refactor data dev resize Refactor device size functions in preparation for similar metadata device resizing functions. Signed-off-by: Joe Thornber Signed-off-by: Alasdair G Kergon --- drivers/md/dm-thin-metadata.c | 10 ++-- drivers/md/dm-thin.c | 87 ++++++++++++++++++++++++----------- 2 files changed, 64 insertions(+), 33 deletions(-) diff --git a/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c index 00cee02f8fc9..9452a489ed99 100644 --- a/drivers/md/dm-thin-metadata.c +++ b/drivers/md/dm-thin-metadata.c @@ -1645,12 +1645,12 @@ int dm_thin_get_highest_mapped_block(struct dm_thin_device *td, return r; } -static int __resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_count) +static int __resize_space_map(struct dm_space_map *sm, dm_block_t new_count) { int r; dm_block_t old_count; - r = dm_sm_get_nr_blocks(pmd->data_sm, &old_count); + r = dm_sm_get_nr_blocks(sm, &old_count); if (r) return r; @@ -1658,11 +1658,11 @@ static int __resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_count) return 0; if (new_count < old_count) { - DMERR("cannot reduce size of data device"); + DMERR("cannot reduce size of space map"); return -EINVAL; } - return dm_sm_extend(pmd->data_sm, new_count - old_count); + return dm_sm_extend(sm, new_count - old_count); } int dm_pool_resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_count) @@ -1671,7 +1671,7 @@ int dm_pool_resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_count) down_write(&pmd->root_lock); if (!pmd->fail_io) - r = __resize_data_dev(pmd, new_count); + r = __resize_space_map(pmd->data_sm, new_count); up_write(&pmd->root_lock); return r; diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index 004ad1652b73..111c148fb1d0 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -922,7 +922,7 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result) return r; if (free_blocks <= pool->low_water_blocks && !pool->low_water_triggered) { - DMWARN("%s: reached low water mark, sending event.", + DMWARN("%s: reached low water mark for data device: sending event.", dm_device_name(pool->pool_md)); spin_lock_irqsave(&pool->lock, flags); pool->low_water_triggered = 1; @@ -1909,6 +1909,20 @@ static int parse_pool_features(struct dm_arg_set *as, struct pool_features *pf, return r; } +static sector_t get_metadata_dev_size(struct block_device *bdev) +{ + sector_t metadata_dev_size = i_size_read(bdev->bd_inode) >> SECTOR_SHIFT; + char buffer[BDEVNAME_SIZE]; + + if (metadata_dev_size > THIN_METADATA_MAX_SECTORS_WARNING) { + DMWARN("Metadata device %s is larger than %u sectors: excess space will not be used.", + bdevname(bdev, buffer), THIN_METADATA_MAX_SECTORS); + metadata_dev_size = THIN_METADATA_MAX_SECTORS_WARNING; + } + + return metadata_dev_size; +} + /* * thin-pool * @@ -1931,8 +1945,6 @@ static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv) unsigned long block_size; dm_block_t low_water_blocks; struct dm_dev *metadata_dev; - sector_t metadata_dev_size; - char b[BDEVNAME_SIZE]; /* * FIXME Remove validation from scope of lock. @@ -1953,10 +1965,11 @@ static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv) goto out_unlock; } - metadata_dev_size = i_size_read(metadata_dev->bdev->bd_inode) >> SECTOR_SHIFT; - if (metadata_dev_size > THIN_METADATA_MAX_SECTORS_WARNING) - DMWARN("Metadata device %s is larger than %u sectors: excess space will not be used.", - bdevname(metadata_dev->bdev, b), THIN_METADATA_MAX_SECTORS); + /* + * Run for the side-effect of possibly issuing a warning if the + * device is too big. + */ + (void) get_metadata_dev_size(metadata_dev->bdev); r = dm_get_device(ti, argv[1], FMODE_READ | FMODE_WRITE, &data_dev); if (r) { @@ -2079,18 +2092,7 @@ static int pool_map(struct dm_target *ti, struct bio *bio) return r; } -/* - * Retrieves the number of blocks of the data device from - * the superblock and compares it to the actual device size, - * thus resizing the data device in case it has grown. - * - * This both copes with opening preallocated data devices in the ctr - * being followed by a resume - * -and- - * calling the resume method individually after userspace has - * grown the data device in reaction to a table event. - */ -static int pool_preresume(struct dm_target *ti) +static int maybe_resize_data_dev(struct dm_target *ti, bool *need_commit) { int r; struct pool_c *pt = ti->private; @@ -2098,12 +2100,7 @@ static int pool_preresume(struct dm_target *ti) sector_t data_size = ti->len; dm_block_t sb_data_size; - /* - * Take control of the pool object. - */ - r = bind_control_target(pool, ti); - if (r) - return r; + *need_commit = false; (void) sector_div(data_size, pool->sectors_per_block); @@ -2114,7 +2111,7 @@ static int pool_preresume(struct dm_target *ti) } if (data_size < sb_data_size) { - DMERR("pool target too small, is %llu blocks (expected %llu)", + DMERR("pool target (%llu blocks) too small: expected %llu", (unsigned long long)data_size, sb_data_size); return -EINVAL; @@ -2122,17 +2119,51 @@ static int pool_preresume(struct dm_target *ti) r = dm_pool_resize_data_dev(pool->pmd, data_size); if (r) { DMERR("failed to resize data device"); - /* FIXME Stricter than necessary: Rollback transaction instead here */ set_pool_mode(pool, PM_READ_ONLY); return r; } - (void) commit_or_fallback(pool); + *need_commit = true; } return 0; } +/* + * Retrieves the number of blocks of the data device from + * the superblock and compares it to the actual device size, + * thus resizing the data device in case it has grown. + * + * This both copes with opening preallocated data devices in the ctr + * being followed by a resume + * -and- + * calling the resume method individually after userspace has + * grown the data device in reaction to a table event. + */ +static int pool_preresume(struct dm_target *ti) +{ + int r; + bool need_commit1; + struct pool_c *pt = ti->private; + struct pool *pool = pt->pool; + + /* + * Take control of the pool object. + */ + r = bind_control_target(pool, ti); + if (r) + return r; + + r = maybe_resize_data_dev(ti, &need_commit1); + if (r) + return r; + + if (need_commit1) + (void) commit_or_fallback(pool); + + return 0; +} + static void pool_resume(struct dm_target *ti) { struct pool_c *pt = ti->private; -- GitLab