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Diffstat (limited to 'drivers/md/dm-thin.c')
-rw-r--r--drivers/md/dm-thin.c105
1 files changed, 69 insertions, 36 deletions
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index ce59824fb414..93e3e542cff9 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,
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