dm exception store: move chunk_fields
Move chunk fields from snapshot to exception store.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 4429c2a..7a90fed 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -468,7 +468,7 @@
/*
* Allocate room for a suitable hash table.
*/
-static int init_hash_tables(struct dm_snapshot *s)
+static int init_hash_tables(struct dm_snapshot *s, chunk_t chunk_shift)
{
sector_t hash_size, cow_dev_size, origin_dev_size, max_buckets;
@@ -480,7 +480,7 @@
origin_dev_size = get_dev_size(s->origin->bdev);
max_buckets = calc_max_buckets();
- hash_size = min(origin_dev_size, cow_dev_size) >> s->chunk_shift;
+ hash_size = min(origin_dev_size, cow_dev_size) >> chunk_shift;
hash_size = min(hash_size, max_buckets);
hash_size = rounddown_pow_of_two(hash_size);
@@ -515,19 +515,20 @@
}
static int set_chunk_size(struct dm_snapshot *s, const char *chunk_size_arg,
- char **error)
+ chunk_t *chunk_size, chunk_t *chunk_mask,
+ chunk_t *chunk_shift, char **error)
{
- unsigned long chunk_size;
+ unsigned long chunk_size_ulong;
char *value;
- chunk_size = simple_strtoul(chunk_size_arg, &value, 10);
+ chunk_size_ulong = simple_strtoul(chunk_size_arg, &value, 10);
if (*chunk_size_arg == '\0' || *value != '\0') {
*error = "Invalid chunk size";
return -EINVAL;
}
- if (!chunk_size) {
- s->chunk_size = s->chunk_mask = s->chunk_shift = 0;
+ if (!chunk_size_ulong) {
+ *chunk_size = *chunk_mask = *chunk_shift = 0;
return 0;
}
@@ -535,23 +536,23 @@
* Chunk size must be multiple of page size. Silently
* round up if it's not.
*/
- chunk_size = round_up(chunk_size, PAGE_SIZE >> 9);
+ chunk_size_ulong = round_up(chunk_size_ulong, PAGE_SIZE >> 9);
/* Check chunk_size is a power of 2 */
- if (!is_power_of_2(chunk_size)) {
+ if (!is_power_of_2(chunk_size_ulong)) {
*error = "Chunk size is not a power of 2";
return -EINVAL;
}
/* Validate the chunk size against the device block size */
- if (chunk_size % (bdev_hardsect_size(s->cow->bdev) >> 9)) {
+ if (chunk_size_ulong % (bdev_hardsect_size(s->cow->bdev) >> 9)) {
*error = "Chunk size is not a multiple of device blocksize";
return -EINVAL;
}
- s->chunk_size = chunk_size;
- s->chunk_mask = chunk_size - 1;
- s->chunk_shift = ffs(chunk_size) - 1;
+ *chunk_size = chunk_size_ulong;
+ *chunk_mask = chunk_size_ulong - 1;
+ *chunk_shift = ffs(chunk_size_ulong) - 1;
return 0;
}
@@ -567,6 +568,7 @@
char persistent;
char *origin_path;
char *cow_path;
+ chunk_t chunk_size, chunk_mask, chunk_shift;
if (argc != 4) {
ti->error = "requires exactly 4 arguments";
@@ -606,7 +608,8 @@
goto bad2;
}
- r = set_chunk_size(s, argv[3], &ti->error);
+ r = set_chunk_size(s, argv[3], &chunk_size, &chunk_mask, &chunk_shift,
+ &ti->error);
if (r)
goto bad3;
@@ -617,13 +620,14 @@
spin_lock_init(&s->pe_lock);
/* Allocate hash table for COW data */
- if (init_hash_tables(s)) {
+ if (init_hash_tables(s, chunk_shift)) {
ti->error = "Unable to allocate hash table space";
r = -ENOMEM;
goto bad3;
}
- r = dm_exception_store_create(argv[2], ti, &s->store);
+ r = dm_exception_store_create(argv[2], ti, chunk_size, chunk_mask,
+ chunk_shift, &s->store);
if (r) {
ti->error = "Couldn't create exception store";
r = -EINVAL;
@@ -680,7 +684,7 @@
}
ti->private = s;
- ti->split_io = s->chunk_size;
+ ti->split_io = s->store->chunk_size;
return 0;
@@ -955,7 +959,7 @@
src.bdev = bdev;
src.sector = chunk_to_sector(s, pe->e.old_chunk);
- src.count = min(s->chunk_size, dev_size - src.sector);
+ src.count = min(s->store->chunk_size, dev_size - src.sector);
dest.bdev = s->cow->bdev;
dest.sector = chunk_to_sector(s, pe->e.new_chunk);
@@ -1021,7 +1025,7 @@
bio->bi_bdev = s->cow->bdev;
bio->bi_sector = chunk_to_sector(s, dm_chunk_number(e->new_chunk) +
(chunk - e->old_chunk)) +
- (bio->bi_sector & s->chunk_mask);
+ (bio->bi_sector & s->store->chunk_mask);
}
static int snapshot_map(struct dm_target *ti, struct bio *bio,
@@ -1166,7 +1170,7 @@
snprintf(result, maxlen, "%s %s %s %llu",
snap->origin->name, snap->cow->name,
snap->store->type->name,
- (unsigned long long)snap->chunk_size);
+ (unsigned long long)snap->store->chunk_size);
break;
}
@@ -1377,7 +1381,8 @@
o = __lookup_origin(dev->bdev);
if (o)
list_for_each_entry (snap, &o->snapshots, list)
- chunk_size = min_not_zero(chunk_size, snap->chunk_size);
+ chunk_size = min_not_zero(chunk_size,
+ snap->store->chunk_size);
up_read(&_origins_lock);
ti->split_io = chunk_size;