From b2a114652940ccf7e9668ad447ca78bf16a31139 Mon Sep 17 00:00:00 2001 From: Jonathan Brassow Date: Thu, 2 Apr 2009 19:55:30 +0100 Subject: dm exception store: separate type from instance Introduce struct dm_exception_store_type. Signed-off-by: Jonathan Brassow Signed-off-by: Alasdair G Kergon --- drivers/md/dm-exception-store.h | 13 +++++++++++-- drivers/md/dm-snap-persistent.c | 13 +++++++------ drivers/md/dm-snap-transient.c | 14 +++++++------- drivers/md/dm-snap.c | 20 ++++++++++---------- 4 files changed, 35 insertions(+), 25 deletions(-) (limited to 'drivers/md') diff --git a/drivers/md/dm-exception-store.h b/drivers/md/dm-exception-store.h index bb9f33d5daa..aed1f1172f9 100644 --- a/drivers/md/dm-exception-store.h +++ b/drivers/md/dm-exception-store.h @@ -37,11 +37,15 @@ struct dm_snap_exception { * Abstraction to handle the meta/layout of exception stores (the * COW device). */ -struct dm_exception_store { +struct dm_exception_store; +struct dm_exception_store_type { + int (*ctr) (struct dm_exception_store *store, + unsigned argc, char **argv); + /* * Destroys this object when you've finished with it. */ - void (*destroy) (struct dm_exception_store *store); + void (*dtr) (struct dm_exception_store *store); /* * The target shouldn't read the COW device until this is @@ -81,8 +85,13 @@ struct dm_exception_store { void (*fraction_full) (struct dm_exception_store *store, sector_t *numerator, sector_t *denominator); +}; + +struct dm_exception_store { + struct dm_exception_store_type type; struct dm_snapshot *snap; + void *context; }; diff --git a/drivers/md/dm-snap-persistent.c b/drivers/md/dm-snap-persistent.c index 936b34e0959..0bbbe3b7431 100644 --- a/drivers/md/dm-snap-persistent.c +++ b/drivers/md/dm-snap-persistent.c @@ -683,12 +683,13 @@ int dm_create_persistent(struct dm_exception_store *store) return -ENOMEM; } - store->destroy = persistent_destroy; - store->read_metadata = persistent_read_metadata; - store->prepare_exception = persistent_prepare_exception; - store->commit_exception = persistent_commit_exception; - store->drop_snapshot = persistent_drop_snapshot; - store->fraction_full = persistent_fraction_full; + store->type.dtr = persistent_destroy; + store->type.read_metadata = persistent_read_metadata; + store->type.prepare_exception = persistent_prepare_exception; + store->type.commit_exception = persistent_commit_exception; + store->type.drop_snapshot = persistent_drop_snapshot; + store->type.fraction_full = persistent_fraction_full; + store->context = ps; return 0; diff --git a/drivers/md/dm-snap-transient.c b/drivers/md/dm-snap-transient.c index 7f6e2e6dcb0..b558176ff02 100644 --- a/drivers/md/dm-snap-transient.c +++ b/drivers/md/dm-snap-transient.c @@ -39,7 +39,7 @@ static int transient_read_metadata(struct dm_exception_store *store, static int transient_prepare_exception(struct dm_exception_store *store, struct dm_snap_exception *e) { - struct transient_c *tc = (struct transient_c *) store->context; + struct transient_c *tc = store->context; sector_t size = get_dev_size(store->snap->cow->bdev); if (size < (tc->next_free + store->snap->chunk_size)) @@ -71,12 +71,12 @@ int dm_create_transient(struct dm_exception_store *store) { struct transient_c *tc; - store->destroy = transient_destroy; - store->read_metadata = transient_read_metadata; - store->prepare_exception = transient_prepare_exception; - store->commit_exception = transient_commit_exception; - store->drop_snapshot = NULL; - store->fraction_full = transient_fraction_full; + store->type.dtr = transient_destroy; + store->type.read_metadata = transient_read_metadata; + store->type.prepare_exception = transient_prepare_exception; + store->type.commit_exception = transient_commit_exception; + store->type.drop_snapshot = NULL; + store->type.fraction_full = transient_fraction_full; tc = kmalloc(sizeof(struct transient_c), GFP_KERNEL); if (!tc) diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index 462750c6631..dabd58e9aaf 100644 --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -665,7 +665,7 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv) spin_lock_init(&s->tracked_chunk_lock); /* Metadata must only be loaded into one table at once */ - r = s->store.read_metadata(&s->store, dm_add_exception, (void *)s); + r = s->store.type.read_metadata(&s->store, dm_add_exception, (void *)s); if (r < 0) { ti->error = "Failed to read snapshot metadata"; goto bad_load_and_register; @@ -700,7 +700,7 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv) dm_kcopyd_client_destroy(s->kcopyd_client); bad5: - s->store.destroy(&s->store); + s->store.type.dtr(&s->store); bad4: exit_exception_table(&s->pending, pending_cache); @@ -725,7 +725,7 @@ static void __free_exceptions(struct dm_snapshot *s) exit_exception_table(&s->pending, pending_cache); exit_exception_table(&s->complete, exception_cache); - s->store.destroy(&s->store); + s->store.type.dtr(&s->store); } static void snapshot_dtr(struct dm_target *ti) @@ -820,8 +820,8 @@ static void __invalidate_snapshot(struct dm_snapshot *s, int err) else if (err == -ENOMEM) DMERR("Invalidating snapshot: Unable to allocate exception."); - if (s->store.drop_snapshot) - s->store.drop_snapshot(&s->store); + if (s->store.type.drop_snapshot) + s->store.type.drop_snapshot(&s->store); s->valid = 0; @@ -943,8 +943,8 @@ static void copy_callback(int read_err, unsigned long write_err, void *context) else /* Update the metadata if we are persistent */ - s->store.commit_exception(&s->store, &pe->e, commit_callback, - pe); + s->store.type.commit_exception(&s->store, &pe->e, + commit_callback, pe); } /* @@ -1010,7 +1010,7 @@ __find_pending_exception(struct dm_snapshot *s, atomic_set(&pe->ref_count, 0); pe->started = 0; - if (s->store.prepare_exception(&s->store, &pe->e)) { + if (s->store.type.prepare_exception(&s->store, &pe->e)) { free_pending_exception(pe); return NULL; } @@ -1149,9 +1149,9 @@ static int snapshot_status(struct dm_target *ti, status_type_t type, if (!snap->valid) snprintf(result, maxlen, "Invalid"); else { - if (snap->store.fraction_full) { + if (snap->store.type.fraction_full) { sector_t numerator, denominator; - snap->store.fraction_full(&snap->store, + snap->store.type.fraction_full(&snap->store, &numerator, &denominator); snprintf(result, maxlen, "%llu/%llu", -- cgit v1.2.3