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path: root/drivers/md/dm-snap.c
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Diffstat (limited to 'drivers/md/dm-snap.c')
-rw-r--r--drivers/md/dm-snap.c90
1 files changed, 34 insertions, 56 deletions
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index a143921feaf6..59fc18ae52c2 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -79,7 +79,6 @@ struct dm_snapshot {
/* Chunks with outstanding reads */
spinlock_t tracked_chunk_lock;
- mempool_t *tracked_chunk_pool;
struct hlist_head tracked_chunk_hash[DM_TRACKED_CHUNK_HASH_SIZE];
/* The on disk metadata handler */
@@ -191,35 +190,38 @@ struct dm_snap_tracked_chunk {
chunk_t chunk;
};
-static struct kmem_cache *tracked_chunk_cache;
+static void init_tracked_chunk(struct bio *bio)
+{
+ struct dm_snap_tracked_chunk *c = dm_per_bio_data(bio, sizeof(struct dm_snap_tracked_chunk));
+ INIT_HLIST_NODE(&c->node);
+}
-static struct dm_snap_tracked_chunk *track_chunk(struct dm_snapshot *s,
- chunk_t chunk)
+static bool is_bio_tracked(struct bio *bio)
{
- struct dm_snap_tracked_chunk *c = mempool_alloc(s->tracked_chunk_pool,
- GFP_NOIO);
- unsigned long flags;
+ struct dm_snap_tracked_chunk *c = dm_per_bio_data(bio, sizeof(struct dm_snap_tracked_chunk));
+ return !hlist_unhashed(&c->node);
+}
+
+static void track_chunk(struct dm_snapshot *s, struct bio *bio, chunk_t chunk)
+{
+ struct dm_snap_tracked_chunk *c = dm_per_bio_data(bio, sizeof(struct dm_snap_tracked_chunk));
c->chunk = chunk;
- spin_lock_irqsave(&s->tracked_chunk_lock, flags);
+ spin_lock_irq(&s->tracked_chunk_lock);
hlist_add_head(&c->node,
&s->tracked_chunk_hash[DM_TRACKED_CHUNK_HASH(chunk)]);
- spin_unlock_irqrestore(&s->tracked_chunk_lock, flags);
-
- return c;
+ spin_unlock_irq(&s->tracked_chunk_lock);
}
-static void stop_tracking_chunk(struct dm_snapshot *s,
- struct dm_snap_tracked_chunk *c)
+static void stop_tracking_chunk(struct dm_snapshot *s, struct bio *bio)
{
+ struct dm_snap_tracked_chunk *c = dm_per_bio_data(bio, sizeof(struct dm_snap_tracked_chunk));
unsigned long flags;
spin_lock_irqsave(&s->tracked_chunk_lock, flags);
hlist_del(&c->node);
spin_unlock_irqrestore(&s->tracked_chunk_lock, flags);
-
- mempool_free(c, s->tracked_chunk_pool);
}
static int __chunk_is_tracked(struct dm_snapshot *s, chunk_t chunk)
@@ -1120,14 +1122,6 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
goto bad_pending_pool;
}
- s->tracked_chunk_pool = mempool_create_slab_pool(MIN_IOS,
- tracked_chunk_cache);
- if (!s->tracked_chunk_pool) {
- ti->error = "Could not allocate tracked_chunk mempool for "
- "tracking reads";
- goto bad_tracked_chunk_pool;
- }
-
for (i = 0; i < DM_TRACKED_CHUNK_HASH_SIZE; i++)
INIT_HLIST_HEAD(&s->tracked_chunk_hash[i]);
@@ -1135,6 +1129,7 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
ti->private = s;
ti->num_flush_requests = num_flush_requests;
+ ti->per_bio_data_size = sizeof(struct dm_snap_tracked_chunk);
/* Add snapshot to the list of snapshots for this origin */
/* Exceptions aren't triggered till snapshot_resume() is called */
@@ -1183,9 +1178,6 @@ bad_read_metadata:
unregister_snapshot(s);
bad_load_and_register:
- mempool_destroy(s->tracked_chunk_pool);
-
-bad_tracked_chunk_pool:
mempool_destroy(s->pending_pool);
bad_pending_pool:
@@ -1290,8 +1282,6 @@ static void snapshot_dtr(struct dm_target *ti)
BUG_ON(!hlist_empty(&s->tracked_chunk_hash[i]));
#endif
- mempool_destroy(s->tracked_chunk_pool);
-
__free_exceptions(s);
mempool_destroy(s->pending_pool);
@@ -1577,8 +1567,7 @@ static void remap_exception(struct dm_snapshot *s, struct dm_exception *e,
s->store->chunk_mask);
}
-static int snapshot_map(struct dm_target *ti, struct bio *bio,
- union map_info *map_context)
+static int snapshot_map(struct dm_target *ti, struct bio *bio)
{
struct dm_exception *e;
struct dm_snapshot *s = ti->private;
@@ -1586,6 +1575,8 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio,
chunk_t chunk;
struct dm_snap_pending_exception *pe = NULL;
+ init_tracked_chunk(bio);
+
if (bio->bi_rw & REQ_FLUSH) {
bio->bi_bdev = s->cow->bdev;
return DM_MAPIO_REMAPPED;
@@ -1670,7 +1661,7 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio,
}
} else {
bio->bi_bdev = s->origin->bdev;
- map_context->ptr = track_chunk(s, chunk);
+ track_chunk(s, bio, chunk);
}
out_unlock:
@@ -1691,20 +1682,20 @@ out:
* If merging is currently taking place on the chunk in question, the
* I/O is deferred by adding it to s->bios_queued_during_merge.
*/
-static int snapshot_merge_map(struct dm_target *ti, struct bio *bio,
- union map_info *map_context)
+static int snapshot_merge_map(struct dm_target *ti, struct bio *bio)
{
struct dm_exception *e;
struct dm_snapshot *s = ti->private;
int r = DM_MAPIO_REMAPPED;
chunk_t chunk;
+ init_tracked_chunk(bio);
+
if (bio->bi_rw & REQ_FLUSH) {
- if (!map_context->target_request_nr)
+ if (!dm_bio_get_target_request_nr(bio))
bio->bi_bdev = s->origin->bdev;
else
bio->bi_bdev = s->cow->bdev;
- map_context->ptr = NULL;
return DM_MAPIO_REMAPPED;
}
@@ -1733,7 +1724,7 @@ static int snapshot_merge_map(struct dm_target *ti, struct bio *bio,
remap_exception(s, e, bio, chunk);
if (bio_rw(bio) == WRITE)
- map_context->ptr = track_chunk(s, chunk);
+ track_chunk(s, bio, chunk);
goto out_unlock;
}
@@ -1751,14 +1742,12 @@ out_unlock:
return r;
}
-static int snapshot_end_io(struct dm_target *ti, struct bio *bio,
- int error, union map_info *map_context)
+static int snapshot_end_io(struct dm_target *ti, struct bio *bio, int error)
{
struct dm_snapshot *s = ti->private;
- struct dm_snap_tracked_chunk *c = map_context->ptr;
- if (c)
- stop_tracking_chunk(s, c);
+ if (is_bio_tracked(bio))
+ stop_tracking_chunk(s, bio);
return 0;
}
@@ -2127,8 +2116,7 @@ static void origin_dtr(struct dm_target *ti)
dm_put_device(ti, dev);
}
-static int origin_map(struct dm_target *ti, struct bio *bio,
- union map_info *map_context)
+static int origin_map(struct dm_target *ti, struct bio *bio)
{
struct dm_dev *dev = ti->private;
bio->bi_bdev = dev->bdev;
@@ -2193,7 +2181,7 @@ static int origin_iterate_devices(struct dm_target *ti,
static struct target_type origin_target = {
.name = "snapshot-origin",
- .version = {1, 7, 1},
+ .version = {1, 8, 0},
.module = THIS_MODULE,
.ctr = origin_ctr,
.dtr = origin_dtr,
@@ -2206,7 +2194,7 @@ static struct target_type origin_target = {
static struct target_type snapshot_target = {
.name = "snapshot",
- .version = {1, 10, 0},
+ .version = {1, 11, 0},
.module = THIS_MODULE,
.ctr = snapshot_ctr,
.dtr = snapshot_dtr,
@@ -2220,7 +2208,7 @@ static struct target_type snapshot_target = {
static struct target_type merge_target = {
.name = dm_snapshot_merge_target_name,
- .version = {1, 1, 0},
+ .version = {1, 2, 0},
.module = THIS_MODULE,
.ctr = snapshot_ctr,
.dtr = snapshot_dtr,
@@ -2281,17 +2269,8 @@ static int __init dm_snapshot_init(void)
goto bad_pending_cache;
}
- tracked_chunk_cache = KMEM_CACHE(dm_snap_tracked_chunk, 0);
- if (!tracked_chunk_cache) {
- DMERR("Couldn't create cache to track chunks in use.");
- r = -ENOMEM;
- goto bad_tracked_chunk_cache;
- }
-
return 0;
-bad_tracked_chunk_cache:
- kmem_cache_destroy(pending_cache);
bad_pending_cache:
kmem_cache_destroy(exception_cache);
bad_exception_cache:
@@ -2317,7 +2296,6 @@ static void __exit dm_snapshot_exit(void)
exit_origin_hash();
kmem_cache_destroy(pending_cache);
kmem_cache_destroy(exception_cache);
- kmem_cache_destroy(tracked_chunk_cache);
dm_exception_store_exit();
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-18 11:16:53 +0300