From patchwork Tue Mar 17 14:03:01 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jonthan Brassow X-Patchwork-Id: 12606 Received: from hormel.redhat.com (hormel1.redhat.com [209.132.177.33]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n2HE35lG018450 for ; Tue, 17 Mar 2009 14:03:05 GMT Received: from listman.util.phx.redhat.com (listman.util.phx.redhat.com [10.8.4.110]) by hormel.redhat.com (Postfix) with ESMTP id 72120619A8A; Tue, 17 Mar 2009 10:03:06 -0400 (EDT) Received: from int-mx2.corp.redhat.com (nat-pool.util.phx.redhat.com [10.8.5.200]) by listman.util.phx.redhat.com (8.13.1/8.13.1) with ESMTP id n2HE34Jn023083 for ; Tue, 17 Mar 2009 10:03:04 -0400 Received: from hydrogen.msp.redhat.com (hydrogen.msp.redhat.com [10.15.80.1]) by int-mx2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n2HE31nW011107 for ; Tue, 17 Mar 2009 10:03:02 -0400 Received: from hydrogen.msp.redhat.com (localhost.localdomain [127.0.0.1]) by hydrogen.msp.redhat.com (8.14.1/8.14.1) with ESMTP id n2HE31Hs017362 for ; Tue, 17 Mar 2009 09:03:01 -0500 Received: (from jbrassow@localhost) by hydrogen.msp.redhat.com (8.14.1/8.14.1/Submit) id n2HE31MT017360 for dm-devel@redhat.com; Tue, 17 Mar 2009 09:03:01 -0500 Date: Tue, 17 Mar 2009 09:03:01 -0500 From: Jonathan Brassow Message-Id: <200903171403.n2HE31MT017360@hydrogen.msp.redhat.com> To: dm-devel@redhat.com X-Scanned-By: MIMEDefang 2.58 on 172.16.27.26 X-loop: dm-devel@redhat.com Subject: [dm-devel] [PATCH 5 of 29] dm-snap-exception_table-ptrs.patch X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.5 Precedence: junk Reply-To: device-mapper development List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com Change to using exception table pointers vs. just using the whole struct from within 'stuct dm_snapshot'. Again, this is to facilitate extraction of the exception table/cache code from dm-snap.c. RFC-by: Jonathan Brassow --- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel Index: linux-2.6/drivers/md/dm-snap.c =================================================================== --- linux-2.6.orig/drivers/md/dm-snap.c +++ linux-2.6/drivers/md/dm-snap.c @@ -75,8 +75,8 @@ struct dm_snapshot { atomic_t pending_exceptions_count; - struct dm_exception_table pending; - struct dm_exception_table complete; + struct dm_exception_table *pending; + struct dm_exception_table *complete; /* * pe_lock protects all pending_exception operations and access @@ -348,25 +348,32 @@ static void unregister_snapshot(struct d * The lowest hash_shift bits of the chunk number are ignored, allowing * some consecutive chunks to be grouped together. */ -static int dm_exception_table_init(struct dm_exception_table *et, - uint32_t size, unsigned hash_shift) +static struct dm_exception_table * +dm_exception_table_create(uint32_t size, unsigned hash_shift) { unsigned int i; + struct dm_exception_table *et; + + et = kmalloc(sizeof(*et), GFP_KERNEL); + if (!et) + return NULL; et->hash_shift = hash_shift; et->hash_mask = size - 1; et->table = dm_vcalloc(size, sizeof(struct list_head)); - if (!et->table) - return -ENOMEM; + if (!et->table) { + kfree(et); + return NULL; + } for (i = 0; i < size; i++) INIT_LIST_HEAD(et->table + i); - return 0; + return et; } -static void dm_exception_table_exit(struct dm_exception_table *et, - struct kmem_cache *mem) +static void dm_exception_table_destroy(struct dm_exception_table *et, + struct kmem_cache *mem) { struct list_head *slot; struct dm_exception *ex, *next; @@ -381,6 +388,7 @@ static void dm_exception_table_exit(stru } vfree(et->table); + kfree(et); } static uint32_t exception_hash(struct dm_exception_table *et, chunk_t chunk) @@ -508,7 +516,7 @@ static int dm_add_exception(void *contex /* Consecutive_count is implicitly initialised to zero */ e->new_chunk = new; - dm_insert_exception(&s->complete, e); + dm_insert_exception(s->complete, e); return 0; } @@ -544,8 +552,10 @@ static int init_hash_tables(struct dm_sn hash_size = min(hash_size, max_buckets); hash_size = rounddown_pow_of_two(hash_size); - if (dm_exception_table_init(&s->complete, hash_size, - DM_CHUNK_CONSECUTIVE_BITS)) + + s->complete = dm_exception_table_create(hash_size, + DM_CHUNK_CONSECUTIVE_BITS); + if (!s->complete) return -ENOMEM; /* @@ -556,8 +566,9 @@ static int init_hash_tables(struct dm_sn if (hash_size < 64) hash_size = 64; - if (dm_exception_table_init(&s->pending, hash_size, 0)) { - dm_exception_table_exit(&s->complete, exception_cache); + s->pending = dm_exception_table_create(hash_size, 0); + if (!s->pending) { + dm_exception_table_destroy(s->complete, exception_cache); return -ENOMEM; } @@ -749,8 +760,8 @@ bad_pending_pool: dm_kcopyd_client_destroy(s->kcopyd_client); bad_kcopyd: - dm_exception_table_exit(&s->pending, pending_cache); - dm_exception_table_exit(&s->complete, exception_cache); + dm_exception_table_destroy(s->pending, pending_cache); + dm_exception_table_destroy(s->complete, exception_cache); bad_hash_tables: dm_put_device(ti, s->origin); @@ -769,8 +780,8 @@ static void __free_exceptions(struct dm_ dm_kcopyd_client_destroy(s->kcopyd_client); s->kcopyd_client = NULL; - dm_exception_table_exit(&s->pending, pending_cache); - dm_exception_table_exit(&s->complete, exception_cache); + dm_exception_table_destroy(s->pending, pending_cache); + dm_exception_table_destroy(s->complete, exception_cache); } static void snapshot_dtr(struct dm_target *ti) @@ -950,7 +961,7 @@ static void pending_complete(struct dm_s * Add a proper exception, and remove the * in-flight exception from the list. */ - dm_insert_exception(&s->complete, e); + dm_insert_exception(s->complete, e); out: dm_remove_exception(&pe->e); @@ -1036,7 +1047,7 @@ __find_pending_exception(struct dm_snaps /* * Is there a pending exception for this already ? */ - e = dm_lookup_exception(&s->pending, chunk); + e = dm_lookup_exception(s->pending, chunk); if (e) { /* cast the exception to a pending exception */ pe = container_of(e, struct dm_snap_pending_exception, e); @@ -1056,7 +1067,7 @@ __find_pending_exception(struct dm_snaps return NULL; } - e = dm_lookup_exception(&s->pending, chunk); + e = dm_lookup_exception(s->pending, chunk); if (e) { free_pending_exception(pe); pe = container_of(e, struct dm_snap_pending_exception, e); @@ -1076,7 +1087,7 @@ __find_pending_exception(struct dm_snaps } get_pending_exception(pe); - dm_insert_exception(&s->pending, &pe->e); + dm_insert_exception(s->pending, &pe->e); out: return pe; @@ -1119,7 +1130,7 @@ static int snapshot_map(struct dm_target } /* If the block is already remapped - use that, else remap it */ - e = dm_lookup_exception(&s->complete, chunk); + e = dm_lookup_exception(s->complete, chunk); if (e) { remap_exception(s, e, bio, chunk); goto out_unlock; @@ -1261,7 +1272,7 @@ static int __origin_write(struct list_he * ref_count is initialised to 1 so pending_complete() * won't destroy the primary_pe while we're inside this loop. */ - e = dm_lookup_exception(&snap->complete, chunk); + e = dm_lookup_exception(snap->complete, chunk); if (e) goto next_snapshot;