#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
+#include <linux/vmalloc.h>
#define DM_MSG_PREFIX "thin"
/*
* 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
struct hlist_node list;
struct bio_prison *prison;
struct cell_key key;
- unsigned count;
+ struct bio *holder;
struct bio_list bios;
};
{
unsigned i;
uint32_t nr_buckets = calc_nr_buckets(nr_cells);
- size_t len = sizeof(struct bio_prison) +
- (sizeof(struct hlist_head) * nr_buckets);
- struct bio_prison *prison = kmalloc(len, GFP_KERNEL);
+ struct bio_prison *prison = kmalloc(sizeof(*prison), GFP_KERNEL);
if (!prison)
return NULL;
return NULL;
}
+ prison->cells = vmalloc(sizeof(*prison->cells) * nr_buckets);
+ if (!prison->cells) {
+ mempool_destroy(prison->cell_pool);
+ kfree(prison);
+ return NULL;
+ }
+
prison->nr_buckets = nr_buckets;
prison->hash_mask = nr_buckets - 1;
- prison->cells = (struct hlist_head *) (prison + 1);
for (i = 0; i < nr_buckets; i++)
INIT_HLIST_HEAD(prison->cells + i);
static void prison_destroy(struct bio_prison *prison)
{
+ vfree(prison->cells);
mempool_destroy(prison->cell_pool);
kfree(prison);
}
* This may block if a new cell needs allocating. You must ensure that
* cells will be unlocked even if the calling thread is blocked.
*
- * Returns the number of entries in the cell prior to the new addition
- * or < 0 on failure.
+ * Returns 1 if the cell was already held, 0 if @inmate is the new holder.
*/
static int bio_detain(struct bio_prison *prison, struct cell_key *key,
struct bio *inmate, struct cell **ref)
{
- int r;
+ int r = 1;
unsigned long flags;
uint32_t hash = hash_key(prison, key);
- struct cell *uninitialized_var(cell), *cell2 = NULL;
+ struct cell *cell, *cell2;
BUG_ON(hash > prison->nr_buckets);
spin_lock_irqsave(&prison->lock, flags);
+
cell = __search_bucket(prison->cells + hash, key);
+ if (cell) {
+ bio_list_add(&cell->bios, inmate);
+ goto out;
+ }
- if (!cell) {
- /*
- * Allocate a new cell
- */
- spin_unlock_irqrestore(&prison->lock, flags);
- cell2 = mempool_alloc(prison->cell_pool, GFP_NOIO);
- spin_lock_irqsave(&prison->lock, flags);
+ /*
+ * Allocate a new cell
+ */
+ spin_unlock_irqrestore(&prison->lock, flags);
+ cell2 = mempool_alloc(prison->cell_pool, GFP_NOIO);
+ spin_lock_irqsave(&prison->lock, flags);
- /*
- * We've been unlocked, so we have to double check that
- * nobody else has inserted this cell in the meantime.
- */
- cell = __search_bucket(prison->cells + hash, key);
+ /*
+ * We've been unlocked, so we have to double check that
+ * nobody else has inserted this cell in the meantime.
+ */
+ cell = __search_bucket(prison->cells + hash, key);
+ if (cell) {
+ mempool_free(cell2, prison->cell_pool);
+ bio_list_add(&cell->bios, inmate);
+ goto out;
+ }
+
+ /*
+ * Use new cell.
+ */
+ cell = cell2;
- if (!cell) {
- cell = cell2;
- cell2 = NULL;
+ cell->prison = prison;
+ memcpy(&cell->key, key, sizeof(cell->key));
+ cell->holder = inmate;
+ bio_list_init(&cell->bios);
+ hlist_add_head(&cell->list, prison->cells + hash);
- cell->prison = prison;
- memcpy(&cell->key, key, sizeof(cell->key));
- cell->count = 0;
- bio_list_init(&cell->bios);
- hlist_add_head(&cell->list, prison->cells + hash);
- }
- }
+ r = 0;
- r = cell->count++;
- bio_list_add(&cell->bios, inmate);
+out:
spin_unlock_irqrestore(&prison->lock, flags);
- if (cell2)
- mempool_free(cell2, prison->cell_pool);
-
*ref = cell;
return r;
hlist_del(&cell->list);
- if (inmates)
+ if (inmates) {
+ bio_list_add(inmates, cell->holder);
bio_list_merge(inmates, &cell->bios);
+ }
mempool_free(cell, prison->cell_pool);
}
* bio may be in the cell. This function releases the cell, and also does
* a sanity check.
*/
+static void __cell_release_singleton(struct cell *cell, struct bio *bio)
+{
+ BUG_ON(cell->holder != bio);
+ BUG_ON(!bio_list_empty(&cell->bios));
+
+ __cell_release(cell, NULL);
+}
+
static void cell_release_singleton(struct cell *cell, struct bio *bio)
{
- struct bio_prison *prison = cell->prison;
- struct bio_list bios;
- struct bio *b;
unsigned long flags;
-
- bio_list_init(&bios);
+ struct bio_prison *prison = cell->prison;
spin_lock_irqsave(&prison->lock, flags);
- __cell_release(cell, &bios);
+ __cell_release_singleton(cell, bio);
spin_unlock_irqrestore(&prison->lock, flags);
+}
+
+/*
+ * Sometimes we don't want the holder, just the additional bios.
+ */
+static void __cell_release_no_holder(struct cell *cell, struct bio_list *inmates)
+{
+ struct bio_prison *prison = cell->prison;
+
+ hlist_del(&cell->list);
+ bio_list_merge(inmates, &cell->bios);
+
+ mempool_free(cell, prison->cell_pool);
+}
- b = bio_list_pop(&bios);
- BUG_ON(b != bio);
- BUG_ON(!bio_list_empty(&bios));
+static void cell_release_no_holder(struct cell *cell, struct bio_list *inmates)
+{
+ unsigned long flags;
+ struct bio_prison *prison = cell->prison;
+
+ spin_lock_irqsave(&prison->lock, flags);
+ __cell_release_no_holder(cell, inmates);
+ spin_unlock_irqrestore(&prison->lock, flags);
}
static void cell_error(struct cell *cell)
* Same as cell_defer above, except it omits one particular detainee,
* a write bio that covers the block and has already been processed.
*/
-static void cell_defer_except(struct thin_c *tc, struct cell *cell,
- struct bio *exception)
+static void cell_defer_except(struct thin_c *tc, struct cell *cell)
{
struct bio_list bios;
- struct bio *bio;
struct pool *pool = tc->pool;
unsigned long flags;
bio_list_init(&bios);
- cell_release(cell, &bios);
spin_lock_irqsave(&pool->lock, flags);
- while ((bio = bio_list_pop(&bios)))
- if (bio != exception)
- bio_list_add(&pool->deferred_bios, bio);
+ cell_release_no_holder(cell, &pool->deferred_bios);
spin_unlock_irqrestore(&pool->lock, flags);
wake_worker(pool);
if (m->err) {
cell_error(m->cell);
- return;
+ goto out;
}
/*
if (r) {
DMERR("dm_thin_insert_block() failed");
cell_error(m->cell);
- return;
+ goto out;
}
/*
* the bios in the cell.
*/
if (bio) {
- cell_defer_except(tc, m->cell, bio);
+ cell_defer_except(tc, m->cell);
bio_endio(bio, 0);
} else
cell_defer(tc, m->cell, m->data_block);
+out:
list_del(&m->list);
mempool_free(m, tc->pool->mapping_pool);
}
*/
if (ensure_next_mapping(pool)) {
spin_lock_irqsave(&pool->lock, flags);
+ bio_list_add(&pool->deferred_bios, bio);
bio_list_merge(&pool->deferred_bios, &bios);
spin_unlock_irqrestore(&pool->lock, flags);
-
break;
}
process_bio(tc, bio);
* <transaction id> <used metadata sectors>/<total metadata sectors>
* <used data sectors>/<total data sectors> <held metadata root>
*/
-static int pool_status(struct dm_target *ti, status_type_t type,
- char *result, unsigned maxlen)
+static void pool_status(struct dm_target *ti, status_type_t type,
+ char *result, unsigned maxlen)
{
int r;
unsigned sz = 0;
switch (type) {
case STATUSTYPE_INFO:
- r = dm_pool_get_metadata_transaction_id(pool->pmd,
- &transaction_id);
- if (r)
- return r;
+ r = dm_pool_get_metadata_transaction_id(pool->pmd, &transaction_id);
+ if (r) {
+ DMERR("dm_pool_get_metadata_transaction_id returned %d", r);
+ goto err;
+ }
- r = dm_pool_get_free_metadata_block_count(pool->pmd,
- &nr_free_blocks_metadata);
- if (r)
- return r;
+ r = dm_pool_get_free_metadata_block_count(pool->pmd, &nr_free_blocks_metadata);
+ if (r) {
+ DMERR("dm_pool_get_free_metadata_block_count returned %d", r);
+ goto err;
+ }
r = dm_pool_get_metadata_dev_size(pool->pmd, &nr_blocks_metadata);
- if (r)
- return r;
+ if (r) {
+ DMERR("dm_pool_get_metadata_dev_size returned %d", r);
+ goto err;
+ }
- r = dm_pool_get_free_block_count(pool->pmd,
- &nr_free_blocks_data);
- if (r)
- return r;
+ r = dm_pool_get_free_block_count(pool->pmd, &nr_free_blocks_data);
+ if (r) {
+ DMERR("dm_pool_get_free_block_count returned %d", r);
+ goto err;
+ }
r = dm_pool_get_data_dev_size(pool->pmd, &nr_blocks_data);
- if (r)
- return r;
+ if (r) {
+ DMERR("dm_pool_get_data_dev_size returned %d", r);
+ goto err;
+ }
r = dm_pool_get_held_metadata_root(pool->pmd, &held_root);
- if (r)
- return r;
+ if (r) {
+ DMERR("dm_pool_get_held_metadata_root returned %d", r);
+ goto err;
+ }
DMEMIT("%llu %llu/%llu %llu/%llu ",
(unsigned long long)transaction_id,
DMEMIT("skip_block_zeroing ");
break;
}
+ return;
- return 0;
+err:
+ DMEMIT("Error");
}
static int pool_iterate_devices(struct dm_target *ti,
.name = "thin-pool",
.features = DM_TARGET_SINGLETON | DM_TARGET_ALWAYS_WRITEABLE |
DM_TARGET_IMMUTABLE,
- .version = {1, 0, 0},
+ .version = {1, 0, 2},
.module = THIS_MODULE,
.ctr = pool_ctr,
.dtr = pool_dtr,
/*
* <nr mapped sectors> <highest mapped sector>
*/
-static int thin_status(struct dm_target *ti, status_type_t type,
- char *result, unsigned maxlen)
+static void thin_status(struct dm_target *ti, status_type_t type,
+ char *result, unsigned maxlen)
{
int r;
ssize_t sz = 0;
switch (type) {
case STATUSTYPE_INFO:
r = dm_thin_get_mapped_count(tc->td, &mapped);
- if (r)
- return r;
+ if (r) {
+ DMERR("dm_thin_get_mapped_count returned %d", r);
+ goto err;
+ }
r = dm_thin_get_highest_mapped_block(tc->td, &highest);
- if (r < 0)
- return r;
+ if (r < 0) {
+ DMERR("dm_thin_get_highest_mapped_block returned %d", r);
+ goto err;
+ }
DMEMIT("%llu ", mapped * tc->pool->sectors_per_block);
if (r)
}
}
- return 0;
+ return;
+
+err:
+ DMEMIT("Error");
}
static int thin_iterate_devices(struct dm_target *ti,
static struct target_type thin_target = {
.name = "thin",
- .version = {1, 0, 0},
+ .version = {1, 0, 2},
.module = THIS_MODULE,
.ctr = thin_ctr,
.dtr = thin_dtr,