diff options
Diffstat (limited to 'drivers/md/dm-thin.c')
| -rw-r--r-- | drivers/md/dm-thin.c | 105 |
1 files changed, 69 insertions, 36 deletions
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index ce59824..93e3e54 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -19,7 +19,7 @@ /* * Tunable constants */ -#define ENDIO_HOOK_POOL_SIZE 10240 +#define ENDIO_HOOK_POOL_SIZE 1024 #define DEFERRED_SET_SIZE 64 #define MAPPING_POOL_SIZE 1024 #define PRISON_CELLS 1024 @@ -510,10 +510,9 @@ struct pool { struct block_device *md_dev; struct dm_pool_metadata *pmd; - uint32_t sectors_per_block; - unsigned block_shift; - dm_block_t offset_mask; dm_block_t low_water_blocks; + uint32_t sectors_per_block; + int sectors_per_block_shift; struct pool_features pf; unsigned low_water_triggered:1; /* A dm event has been sent */ @@ -526,8 +525,8 @@ struct pool { struct work_struct worker; struct delayed_work waker; - unsigned ref_count; unsigned long last_commit_jiffies; + unsigned ref_count; spinlock_t lock; struct bio_list deferred_bios; @@ -679,16 +678,28 @@ static void requeue_io(struct thin_c *tc) static dm_block_t get_bio_block(struct thin_c *tc, struct bio *bio) { - return bio->bi_sector >> tc->pool->block_shift; + sector_t block_nr = bio->bi_sector; + + if (tc->pool->sectors_per_block_shift < 0) + (void) sector_div(block_nr, tc->pool->sectors_per_block); + else + block_nr >>= tc->pool->sectors_per_block_shift; + + return block_nr; } static void remap(struct thin_c *tc, struct bio *bio, dm_block_t block) { struct pool *pool = tc->pool; + sector_t bi_sector = bio->bi_sector; bio->bi_bdev = tc->pool_dev->bdev; - bio->bi_sector = (block << pool->block_shift) + - (bio->bi_sector & pool->offset_mask); + if (tc->pool->sectors_per_block_shift < 0) + bio->bi_sector = (block * pool->sectors_per_block) + + sector_div(bi_sector, pool->sectors_per_block); + else + bio->bi_sector = (block << pool->sectors_per_block_shift) | + (bi_sector & (pool->sectors_per_block - 1)); } static void remap_to_origin(struct thin_c *tc, struct bio *bio) @@ -933,9 +944,7 @@ static void process_prepared(struct pool *pool, struct list_head *head, */ static int io_overlaps_block(struct pool *pool, struct bio *bio) { - return !(bio->bi_sector & pool->offset_mask) && - (bio->bi_size == (pool->sectors_per_block << SECTOR_SHIFT)); - + return bio->bi_size == (pool->sectors_per_block << SECTOR_SHIFT); } static int io_overwrites_block(struct pool *pool, struct bio *bio) @@ -1218,7 +1227,7 @@ static void process_discard(struct thin_c *tc, struct bio *bio) */ m = get_next_mapping(pool); m->tc = tc; - m->pass_discard = (!lookup_result.shared) & pool->pf.discard_passdown; + m->pass_discard = (!lookup_result.shared) && pool->pf.discard_passdown; m->virt_block = block; m->data_block = lookup_result.block; m->cell = cell; @@ -1234,18 +1243,16 @@ static void process_discard(struct thin_c *tc, struct bio *bio) } } else { /* - * This path is hit if people are ignoring - * limits->discard_granularity. It ignores any - * part of the discard that is in a subsequent - * block. + * The DM core makes sure that the discard doesn't span + * a block boundary. So we submit the discard of a + * partial block appropriately. */ - sector_t offset = bio->bi_sector - (block << pool->block_shift); - unsigned remaining = (pool->sectors_per_block - offset) << 9; - bio->bi_size = min(bio->bi_size, remaining); - cell_release_singleton(cell, bio); cell_release_singleton(cell2, bio); - remap_and_issue(tc, bio, lookup_result.block); + if ((!lookup_result.shared) && pool->pf.discard_passdown) + remap_and_issue(tc, bio, lookup_result.block); + else + bio_endio(bio, 0); } break; @@ -1719,8 +1726,10 @@ static struct pool *pool_create(struct mapped_device *pool_md, pool->pmd = pmd; pool->sectors_per_block = block_size; - pool->block_shift = ffs(block_size) - 1; - pool->offset_mask = block_size - 1; + if (block_size & (block_size - 1)) + pool->sectors_per_block_shift = -1; + else + pool->sectors_per_block_shift = __ffs(block_size); pool->low_water_blocks = 0; pool_features_init(&pool->pf); pool->prison = prison_create(PRISON_CELLS); @@ -1825,15 +1834,19 @@ static struct pool *__pool_find(struct mapped_device *pool_md, struct pool *pool = __pool_table_lookup_metadata_dev(metadata_dev); if (pool) { - if (pool->pool_md != pool_md) + if (pool->pool_md != pool_md) { + *error = "metadata device already in use by a pool"; return ERR_PTR(-EBUSY); + } __pool_inc(pool); } else { pool = __pool_table_lookup(pool_md); if (pool) { - if (pool->md_dev != metadata_dev) + if (pool->md_dev != metadata_dev) { + *error = "different pool cannot replace a pool"; return ERR_PTR(-EINVAL); + } __pool_inc(pool); } else { @@ -1964,7 +1977,7 @@ static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv) if (kstrtoul(argv[2], 10, &block_size) || !block_size || block_size < DATA_DEV_BLOCK_SIZE_MIN_SECTORS || block_size > DATA_DEV_BLOCK_SIZE_MAX_SECTORS || - !is_power_of_2(block_size)) { + block_size & (DATA_DEV_BLOCK_SIZE_MIN_SECTORS - 1)) { ti->error = "Invalid block size"; r = -EINVAL; goto out; @@ -2011,6 +2024,15 @@ static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv) goto out_flags_changed; } + /* + * The block layer requires discard_granularity to be a power of 2. + */ + if (pf.discard_enabled && !is_power_of_2(block_size)) { + ti->error = "Discard support must be disabled when the block size is not a power of 2"; + r = -EINVAL; + goto out_flags_changed; + } + pt->pool = pool; pt->ti = ti; pt->metadata_dev = metadata_dev; @@ -2090,7 +2112,8 @@ static int pool_preresume(struct dm_target *ti) int r; struct pool_c *pt = ti->private; struct pool *pool = pt->pool; - dm_block_t data_size, sb_data_size; + sector_t data_size = ti->len; + dm_block_t sb_data_size; /* * Take control of the pool object. @@ -2099,7 +2122,8 @@ static int pool_preresume(struct dm_target *ti) if (r) return r; - data_size = ti->len >> pool->block_shift; + (void) sector_div(data_size, pool->sectors_per_block); + r = dm_pool_get_data_dev_size(pool->pmd, &sb_data_size); if (r) { DMERR("failed to retrieve data device size"); @@ -2108,7 +2132,7 @@ static int pool_preresume(struct dm_target *ti) if (data_size < sb_data_size) { DMERR("pool target too small, is %llu blocks (expected %llu)", - data_size, sb_data_size); + (unsigned long long)data_size, sb_data_size); return -EINVAL; } else if (data_size > sb_data_size) { @@ -2489,7 +2513,8 @@ static void set_discard_limits(struct pool *pool, struct queue_limits *limits) /* * This is just a hint, and not enforced. We have to cope with - * bios that overlap 2 blocks. + * bios that cover a block partially. A discard that spans a block + * boundary is not sent to this target. */ limits->discard_granularity = pool->sectors_per_block << SECTOR_SHIFT; limits->discard_zeroes_data = pool->pf.zero_new_blocks; @@ -2621,13 +2646,19 @@ static int thin_ctr(struct dm_target *ti, unsigned argc, char **argv) goto bad_thin_open; } - ti->split_io = tc->pool->sectors_per_block; + r = dm_set_target_max_io_len(ti, tc->pool->sectors_per_block); + if (r) + goto bad_thin_open; + ti->num_flush_requests = 1; /* In case the pool supports discards, pass them on. */ if (tc->pool->pf.discard_enabled) { ti->discards_supported = 1; ti->num_discard_requests = 1; + ti->discard_zeroes_data_unsupported = 1; + /* Discard requests must be split on a block boundary */ + ti->split_discard_requests = 1; } dm_put(pool_md); @@ -2753,19 +2784,21 @@ static int thin_status(struct dm_target *ti, status_type_t type, static int thin_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data) { - dm_block_t blocks; + sector_t blocks; struct thin_c *tc = ti->private; + struct pool *pool = tc->pool; /* * We can't call dm_pool_get_data_dev_size() since that blocks. So * we follow a more convoluted path through to the pool's target. */ - if (!tc->pool->ti) + if (!pool->ti) return 0; /* nothing is bound */ - blocks = tc->pool->ti->len >> tc->pool->block_shift; + blocks = pool->ti->len; + (void) sector_div(blocks, pool->sectors_per_block); if (blocks) - return fn(ti, tc->pool_dev, 0, tc->pool->sectors_per_block * blocks, data); + return fn(ti, tc->pool_dev, 0, pool->sectors_per_block * blocks, data); return 0; } @@ -2782,7 +2815,7 @@ static void thin_io_hints(struct dm_target *ti, struct queue_limits *limits) static struct target_type thin_target = { .name = "thin", - .version = {1, 1, 0}, + .version = {1, 2, 0}, .module = THIS_MODULE, .ctr = thin_ctr, .dtr = thin_dtr, |
