struct dm_bio_prison_cell {
struct hlist_node list;
- struct dm_bio_prison *prison;
struct dm_cell_key key;
struct bio *holder;
struct bio_list bios;
}
EXPORT_SYMBOL_GPL(dm_bio_prison_destroy);
+struct dm_bio_prison_cell *dm_bio_prison_alloc_cell(struct dm_bio_prison *prison, gfp_t gfp)
+{
+ return mempool_alloc(prison->cell_pool, gfp);
+}
+EXPORT_SYMBOL_GPL(dm_bio_prison_alloc_cell);
+
+void dm_bio_prison_free_cell(struct dm_bio_prison *prison,
+ struct dm_bio_prison_cell *cell)
+{
+ mempool_free(cell, prison->cell_pool);
+}
+EXPORT_SYMBOL_GPL(dm_bio_prison_free_cell);
+
static uint32_t hash_key(struct dm_bio_prison *prison, struct dm_cell_key *key)
{
const unsigned long BIG_PRIME = 4294967291UL;
return NULL;
}
-/*
- * 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 1 if the cell was already held, 0 if @inmate is the new holder.
- */
-int dm_bio_detain(struct dm_bio_prison *prison, struct dm_cell_key *key,
- struct bio *inmate, struct dm_bio_prison_cell **ref)
+static void __setup_new_cell(struct dm_bio_prison *prison,
+ struct dm_cell_key *key,
+ struct bio *holder,
+ uint32_t hash,
+ struct dm_bio_prison_cell *cell)
{
- int r = 1;
- unsigned long flags;
- uint32_t hash = hash_key(prison, key);
- struct dm_bio_prison_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;
- }
+ memcpy(&cell->key, key, sizeof(cell->key));
+ cell->holder = holder;
+ bio_list_init(&cell->bios);
+ hlist_add_head(&cell->list, prison->cells + hash);
+}
- /*
- * Allocate a new cell
- */
- spin_unlock_irqrestore(&prison->lock, flags);
- cell2 = mempool_alloc(prison->cell_pool, GFP_NOIO);
- spin_lock_irqsave(&prison->lock, flags);
+static int __bio_detain(struct dm_bio_prison *prison,
+ struct dm_cell_key *key,
+ struct bio *inmate,
+ struct dm_bio_prison_cell *cell_prealloc,
+ struct dm_bio_prison_cell **cell_result)
+{
+ uint32_t hash = hash_key(prison, key);
+ struct dm_bio_prison_cell *cell;
- /*
- * 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;
+ if (inmate)
+ bio_list_add(&cell->bios, inmate);
+ *cell_result = cell;
+ return 1;
}
- /*
- * Use new cell.
- */
- cell = cell2;
-
- 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);
+ __setup_new_cell(prison, key, inmate, hash, cell_prealloc);
+ *cell_result = cell_prealloc;
+ return 0;
+}
- r = 0;
+static int bio_detain(struct dm_bio_prison *prison,
+ struct dm_cell_key *key,
+ struct bio *inmate,
+ struct dm_bio_prison_cell *cell_prealloc,
+ struct dm_bio_prison_cell **cell_result)
+{
+ int r;
+ unsigned long flags;
-out:
+ spin_lock_irqsave(&prison->lock, flags);
+ r = __bio_detain(prison, key, inmate, cell_prealloc, cell_result);
spin_unlock_irqrestore(&prison->lock, flags);
- *ref = cell;
-
return r;
}
+
+int dm_bio_detain(struct dm_bio_prison *prison,
+ struct dm_cell_key *key,
+ struct bio *inmate,
+ struct dm_bio_prison_cell *cell_prealloc,
+ struct dm_bio_prison_cell **cell_result)
+{
+ return bio_detain(prison, key, inmate, cell_prealloc, cell_result);
+}
EXPORT_SYMBOL_GPL(dm_bio_detain);
/*
* @inmates must have been initialised prior to this call
*/
-static void __cell_release(struct dm_bio_prison_cell *cell, struct bio_list *inmates)
+static void __cell_release(struct dm_bio_prison_cell *cell,
+ struct bio_list *inmates)
{
- struct dm_bio_prison *prison = cell->prison;
-
hlist_del(&cell->list);
if (inmates) {
- bio_list_add(inmates, cell->holder);
+ if (cell->holder)
+ bio_list_add(inmates, cell->holder);
bio_list_merge(inmates, &cell->bios);
}
-
- mempool_free(cell, prison->cell_pool);
}
-void dm_cell_release(struct dm_bio_prison_cell *cell, struct bio_list *bios)
+void dm_cell_release(struct dm_bio_prison *prison,
+ struct dm_bio_prison_cell *cell,
+ struct bio_list *bios)
{
unsigned long flags;
- struct dm_bio_prison *prison = cell->prison;
spin_lock_irqsave(&prison->lock, flags);
__cell_release(cell, bios);
/*
* Sometimes we don't want the holder, just the additional bios.
*/
-static void __cell_release_no_holder(struct dm_bio_prison_cell *cell, struct bio_list *inmates)
+static void __cell_release_no_holder(struct dm_bio_prison_cell *cell,
+ struct bio_list *inmates)
{
- struct dm_bio_prison *prison = cell->prison;
-
hlist_del(&cell->list);
bio_list_merge(inmates, &cell->bios);
-
- mempool_free(cell, prison->cell_pool);
}
-void dm_cell_release_no_holder(struct dm_bio_prison_cell *cell, struct bio_list *inmates)
+void dm_cell_release_no_holder(struct dm_bio_prison *prison,
+ struct dm_bio_prison_cell *cell,
+ struct bio_list *inmates)
{
unsigned long flags;
- struct dm_bio_prison *prison = cell->prison;
spin_lock_irqsave(&prison->lock, flags);
__cell_release_no_holder(cell, inmates);
}
EXPORT_SYMBOL_GPL(dm_cell_release_no_holder);
-void dm_cell_error(struct dm_bio_prison_cell *cell)
+void dm_cell_error(struct dm_bio_prison *prison,
+ struct dm_bio_prison_cell *cell)
{
- struct dm_bio_prison *prison = cell->prison;
struct bio_list bios;
struct bio *bio;
unsigned long flags;
void dm_bio_prison_destroy(struct dm_bio_prison *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.
+ * These two functions just wrap a mempool. This is a transitory step:
+ * Eventually all bio prison clients should manage their own cell memory.
*
- * Returns 1 if the cell was already held, 0 if @inmate is the new holder.
+ * Like mempool_alloc(), dm_bio_prison_alloc_cell() can only fail if called
+ * in interrupt context or passed GFP_NOWAIT.
*/
-int dm_bio_detain(struct dm_bio_prison *prison, struct dm_cell_key *key,
- struct bio *inmate, struct dm_bio_prison_cell **ref);
+struct dm_bio_prison_cell *dm_bio_prison_alloc_cell(struct dm_bio_prison *prison,
+ gfp_t gfp);
+void dm_bio_prison_free_cell(struct dm_bio_prison *prison,
+ struct dm_bio_prison_cell *cell);
-void dm_cell_release(struct dm_bio_prison_cell *cell, struct bio_list *bios);
-void dm_cell_release_no_holder(struct dm_bio_prison_cell *cell, struct bio_list *inmates);
-void dm_cell_error(struct dm_bio_prison_cell *cell);
+/*
+ * An atomic op that combines retrieving a cell, and adding a bio to it.
+ *
+ * Returns 1 if the cell was already held, 0 if @inmate is the new holder.
+ */
+int dm_bio_detain(struct dm_bio_prison *prison,
+ struct dm_cell_key *key,
+ struct bio *inmate,
+ struct dm_bio_prison_cell *cell_prealloc,
+ struct dm_bio_prison_cell **cell_result);
+
+void dm_cell_release(struct dm_bio_prison *prison,
+ struct dm_bio_prison_cell *cell,
+ struct bio_list *bios);
+void dm_cell_release_no_holder(struct dm_bio_prison *prison,
+ struct dm_bio_prison_cell *cell,
+ struct bio_list *inmates);
+void dm_cell_error(struct dm_bio_prison *prison,
+ struct dm_bio_prison_cell *cell);
/*----------------------------------------------------------------*/
/*----------------------------------------------------------------*/
+static int bio_detain(struct pool *pool, struct dm_cell_key *key, struct bio *bio,
+ struct dm_bio_prison_cell **cell_result)
+{
+ int r;
+ struct dm_bio_prison_cell *cell_prealloc;
+
+ /*
+ * Allocate a cell from the prison's mempool.
+ * This might block but it can't fail.
+ */
+ cell_prealloc = dm_bio_prison_alloc_cell(pool->prison, GFP_NOIO);
+
+ r = dm_bio_detain(pool->prison, key, bio, cell_prealloc, cell_result);
+ if (r)
+ /*
+ * We reused an old cell; we can get rid of
+ * the new one.
+ */
+ dm_bio_prison_free_cell(pool->prison, cell_prealloc);
+
+ return r;
+}
+
+static void cell_release(struct pool *pool,
+ struct dm_bio_prison_cell *cell,
+ struct bio_list *bios)
+{
+ dm_cell_release(pool->prison, cell, bios);
+ dm_bio_prison_free_cell(pool->prison, cell);
+}
+
+static void cell_release_no_holder(struct pool *pool,
+ struct dm_bio_prison_cell *cell,
+ struct bio_list *bios)
+{
+ dm_cell_release_no_holder(pool->prison, cell, bios);
+ dm_bio_prison_free_cell(pool->prison, cell);
+}
+
+static void cell_error(struct pool *pool,
+ struct dm_bio_prison_cell *cell)
+{
+ dm_cell_error(pool->prison, cell);
+ dm_bio_prison_free_cell(pool->prison, cell);
+}
+
+/*----------------------------------------------------------------*/
+
/*
* A global list of pools that uses a struct mapped_device as a key.
*/
unsigned long flags;
spin_lock_irqsave(&pool->lock, flags);
- dm_cell_release(cell, &pool->deferred_bios);
+ cell_release(pool, cell, &pool->deferred_bios);
spin_unlock_irqrestore(&tc->pool->lock, flags);
wake_worker(pool);
}
/*
- * Same as cell_defer except it omits the original holder of the cell.
+ * Same as cell_defer above, except it omits the original holder of the cell.
*/
static void cell_defer_no_holder(struct thin_c *tc, struct dm_bio_prison_cell *cell)
{
unsigned long flags;
spin_lock_irqsave(&pool->lock, flags);
- dm_cell_release_no_holder(cell, &pool->deferred_bios);
+ cell_release_no_holder(pool, cell, &pool->deferred_bios);
spin_unlock_irqrestore(&pool->lock, flags);
wake_worker(pool);
{
if (m->bio)
m->bio->bi_end_io = m->saved_bi_end_io;
- dm_cell_error(m->cell);
+ cell_error(m->tc->pool, m->cell);
list_del(&m->list);
mempool_free(m, m->tc->pool->mapping_pool);
}
static void process_prepared_mapping(struct dm_thin_new_mapping *m)
{
struct thin_c *tc = m->tc;
+ struct pool *pool = tc->pool;
struct bio *bio;
int r;
bio->bi_end_io = m->saved_bi_end_io;
if (m->err) {
- dm_cell_error(m->cell);
+ cell_error(pool, m->cell);
goto out;
}
r = dm_thin_insert_block(tc->td, m->virt_block, m->data_block);
if (r) {
DMERR_LIMIT("dm_thin_insert_block() failed");
- dm_cell_error(m->cell);
+ cell_error(pool, m->cell);
goto out;
}
out:
list_del(&m->list);
- mempool_free(m, tc->pool->mapping_pool);
+ mempool_free(m, pool->mapping_pool);
}
static void process_prepared_discard_fail(struct dm_thin_new_mapping *m)
if (r < 0) {
mempool_free(m, pool->mapping_pool);
DMERR_LIMIT("dm_kcopyd_copy() failed");
- dm_cell_error(cell);
+ cell_error(pool, cell);
}
}
}
if (r < 0) {
mempool_free(m, pool->mapping_pool);
DMERR_LIMIT("dm_kcopyd_zero() failed");
- dm_cell_error(cell);
+ cell_error(pool, cell);
}
}
}
spin_unlock_irqrestore(&pool->lock, flags);
}
-static void no_space(struct dm_bio_prison_cell *cell)
+static void no_space(struct pool *pool, struct dm_bio_prison_cell *cell)
{
struct bio *bio;
struct bio_list bios;
bio_list_init(&bios);
- dm_cell_release(cell, &bios);
+ cell_release(pool, cell, &bios);
while ((bio = bio_list_pop(&bios)))
retry_on_resume(bio);
struct dm_thin_new_mapping *m;
build_virtual_key(tc->td, block, &key);
- if (dm_bio_detain(tc->pool->prison, &key, bio, &cell))
+ if (bio_detain(tc->pool, &key, bio, &cell))
return;
r = dm_thin_find_block(tc->td, block, 1, &lookup_result);
* on this block.
*/
build_data_key(tc->td, lookup_result.block, &key2);
- if (dm_bio_detain(tc->pool->prison, &key2, bio, &cell2)) {
+ if (bio_detain(tc->pool, &key2, bio, &cell2)) {
cell_defer_no_holder(tc, cell);
break;
}
break;
case -ENOSPC:
- no_space(cell);
+ no_space(tc->pool, cell);
break;
default:
DMERR_LIMIT("%s: alloc_data_block() failed: error = %d",
__func__, r);
- dm_cell_error(cell);
+ cell_error(tc->pool, cell);
break;
}
}
* of being broken so we have nothing further to do here.
*/
build_data_key(tc->td, lookup_result->block, &key);
- if (dm_bio_detain(pool->prison, &key, bio, &cell))
+ if (bio_detain(pool, &key, bio, &cell))
return;
if (bio_data_dir(bio) == WRITE && bio->bi_size)
{
int r;
dm_block_t data_block;
+ struct pool *pool = tc->pool;
/*
* Remap empty bios (flushes) immediately, without provisioning.
*/
if (!bio->bi_size) {
- inc_all_io_entry(tc->pool, bio);
+ inc_all_io_entry(pool, bio);
cell_defer_no_holder(tc, cell);
remap_and_issue(tc, bio, 0);
break;
case -ENOSPC:
- no_space(cell);
+ no_space(pool, cell);
break;
default:
DMERR_LIMIT("%s: alloc_data_block() failed: error = %d",
__func__, r);
- set_pool_mode(tc->pool, PM_READ_ONLY);
- dm_cell_error(cell);
+ set_pool_mode(pool, PM_READ_ONLY);
+ cell_error(pool, cell);
break;
}
}
static void process_bio(struct thin_c *tc, struct bio *bio)
{
int r;
+ struct pool *pool = tc->pool;
dm_block_t block = get_bio_block(tc, bio);
struct dm_bio_prison_cell *cell;
struct dm_cell_key key;
* being provisioned so we have nothing further to do here.
*/
build_virtual_key(tc->td, block, &key);
- if (dm_bio_detain(tc->pool->prison, &key, bio, &cell))
+ if (bio_detain(pool, &key, bio, &cell))
return;
r = dm_thin_find_block(tc->td, block, 1, &lookup_result);
case 0:
if (lookup_result.shared) {
process_shared_bio(tc, bio, block, &lookup_result);
- cell_defer_no_holder(tc, cell);
+ cell_defer_no_holder(tc, cell); /* FIXME: pass this cell into process_shared? */
} else {
- inc_all_io_entry(tc->pool, bio);
+ inc_all_io_entry(pool, bio);
cell_defer_no_holder(tc, cell);
remap_and_issue(tc, bio, lookup_result.block);
case -ENODATA:
if (bio_data_dir(bio) == READ && tc->origin_dev) {
- inc_all_io_entry(tc->pool, bio);
+ inc_all_io_entry(pool, bio);
cell_defer_no_holder(tc, cell);
remap_to_origin_and_issue(tc, bio);
}
build_virtual_key(tc->td, block, &key);
- if (dm_bio_detain(tc->pool->prison, &key, bio, &cell1))
+ if (bio_detain(tc->pool, &key, bio, &cell1))
return DM_MAPIO_SUBMITTED;
build_data_key(tc->td, result.block, &key);
- if (dm_bio_detain(tc->pool->prison, &key, bio, &cell2)) {
+ if (bio_detain(tc->pool, &key, bio, &cell2)) {
cell_defer_no_holder(tc, cell1);
return DM_MAPIO_SUBMITTED;
}
projects / platform / kernel / linux-exynos.git / commitdiff