dm thin: eliminate the no_free_space flag

The pool's error_if_no_space flag can easily serve the same purpose that
no_free_space did, namely: control whether handle_unserviceable_bio()
will error a bio or requeue it.

This is cleaner since error_if_no_space is established when the pool's
features are processed during table load.  So it avoids managing the
no_free_space flag by taking the pool's spinlock.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This commit is contained in:
Mike Snitzer 2013-12-20 18:09:02 -05:00
parent 787a996cb2
commit 6d16202be7

View File

@ -165,7 +165,6 @@ struct pool {
struct pool_features pf;
bool low_water_triggered:1; /* A dm event has been sent */
bool no_free_space:1; /* bios will be requeued if set */
struct dm_bio_prison *prison;
struct dm_kcopyd_client *copier;
@ -991,10 +990,10 @@ static void handle_unserviceable_bio(struct pool *pool, struct bio *bio)
*/
WARN_ON_ONCE(get_pool_mode(pool) != PM_READ_ONLY);
if (pool->no_free_space)
retry_on_resume(bio);
else
if (pool->pf.error_if_no_space)
bio_io_error(bio);
else
retry_on_resume(bio);
}
static void retry_bios_on_resume(struct pool *pool, struct dm_bio_prison_cell *cell)
@ -1437,18 +1436,6 @@ static void set_pool_mode(struct pool *pool, enum pool_mode mode)
}
}
static void set_no_free_space(struct pool *pool)
{
unsigned long flags;
if (pool->pf.error_if_no_space)
return;
spin_lock_irqsave(&pool->lock, flags);
pool->no_free_space = true;
spin_unlock_irqrestore(&pool->lock, flags);
}
/*
* Rather than calling set_pool_mode directly, use these which describe the
* reason for mode degradation.
@ -1457,7 +1444,6 @@ static void out_of_data_space(struct pool *pool)
{
DMERR_LIMIT("%s: no free data space available.",
dm_device_name(pool->pool_md));
set_no_free_space(pool);
set_pool_mode(pool, PM_READ_ONLY);
}
@ -1470,11 +1456,9 @@ static void metadata_operation_failed(struct pool *pool, const char *op, int r)
if (r == -ENOSPC &&
!dm_pool_get_free_metadata_block_count(pool->pmd, &free_blocks) &&
!free_blocks) {
!free_blocks)
DMERR_LIMIT("%s: no free metadata space available.",
dm_device_name(pool->pool_md));
set_no_free_space(pool);
}
set_pool_mode(pool, PM_READ_ONLY);
}
@ -1819,7 +1803,6 @@ static struct pool *pool_create(struct mapped_device *pool_md,
INIT_LIST_HEAD(&pool->prepared_mappings);
INIT_LIST_HEAD(&pool->prepared_discards);
pool->low_water_triggered = false;
pool->no_free_space = false;
bio_list_init(&pool->retry_on_resume_list);
pool->shared_read_ds = dm_deferred_set_create();
@ -2346,7 +2329,6 @@ static void pool_resume(struct dm_target *ti)
spin_lock_irqsave(&pool->lock, flags);
pool->low_water_triggered = false;
pool->no_free_space = false;
__requeue_bios(pool);
spin_unlock_irqrestore(&pool->lock, flags);