Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm

* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm:
  dm snapshot: extend exception store functions
  dm snapshot: split out exception store implementations
  dm snapshot: rename struct exception_store
  dm snapshot: separate out exception store interface
  dm mpath: move trigger_event to system workqueue
  dm: add name and uuid to sysfs
  dm table: rework reference counting
  dm: support barriers on simple devices
  dm request: extend target interface
  dm request: add caches
  dm ioctl: allow dm_copy_name_and_uuid to return only one field
  dm log: ensure log bitmap fits on log device
  dm log: move region_size validation
  dm log: avoid reinitialising io_req on every operation
  dm: consolidate target deregistration error handling
  dm raid1: fix error count
  dm log: fix dm_io_client leak on error paths
  dm snapshot: change yield to msleep
  dm table: drop reference at unbind

1 files changed, 79 insertions, 22 deletions

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 421c9f02d8ca..51ba1db4b3e7 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1,6 +1,6 @@
 /*
  * Copyright (C) 2001, 2002 Sistina Software (UK) Limited.
- * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
  *
  * This file is released under the GPL.
  */
@@ -32,6 +32,7 @@ static unsigned int _major = 0;
 
 static DEFINE_SPINLOCK(_minor_lock);
 /*
+ * For bio-based dm.
  * One of these is allocated per bio.
  */
 struct dm_io {
@@ -43,6 +44,7 @@ struct dm_io {
 };
 
 /*
+ * For bio-based dm.
  * One of these is allocated per target within a bio.  Hopefully
  * this will be simplified out one day.
  */
@@ -54,6 +56,27 @@ struct dm_target_io {
 
 DEFINE_TRACE(block_bio_complete);
 
+/*
+ * For request-based dm.
+ * One of these is allocated per request.
+ */
+struct dm_rq_target_io {
+        struct mapped_device *md;
+        struct dm_target *ti;
+        struct request *orig, clone;
+        int error;
+        union map_info info;
+};
+
+/*
+ * For request-based dm.
+ * One of these is allocated per bio.
+ */
+struct dm_rq_clone_bio_info {
+        struct bio *orig;
+        struct request *rq;
+};
+
 union map_info *dm_get_mapinfo(struct bio *bio)
 {
         if (bio && bio->bi_private)
@@ -144,11 +167,16 @@ struct mapped_device {
 
         /* forced geometry settings */
         struct hd_geometry geometry;
+
+        /* sysfs handle */
+        struct kobject kobj;
 };
 
 #define MIN_IOS 256
 static struct kmem_cache *_io_cache;
 static struct kmem_cache *_tio_cache;
+static struct kmem_cache *_rq_tio_cache;
+static struct kmem_cache *_rq_bio_info_cache;
 
 static int __init local_init(void)
 {
@@ -164,9 +192,17 @@ static int __init local_init(void)
         if (!_tio_cache)
                 goto out_free_io_cache;
 
+        _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0);
+        if (!_rq_tio_cache)
+                goto out_free_tio_cache;
+
+        _rq_bio_info_cache = KMEM_CACHE(dm_rq_clone_bio_info, 0);
+        if (!_rq_bio_info_cache)
+                goto out_free_rq_tio_cache;
+
         r = dm_uevent_init();
         if (r)
-                goto out_free_tio_cache;
+                goto out_free_rq_bio_info_cache;
 
         _major = major;
         r = register_blkdev(_major, _name);
@@ -180,6 +216,10 @@ static int __init local_init(void)
 
 out_uevent_exit:
         dm_uevent_exit();
+out_free_rq_bio_info_cache:
+        kmem_cache_destroy(_rq_bio_info_cache);
+out_free_rq_tio_cache:
+        kmem_cache_destroy(_rq_tio_cache);
 out_free_tio_cache:
         kmem_cache_destroy(_tio_cache);
 out_free_io_cache:
@@ -190,6 +230,8 @@ out_free_io_cache:
 
 static void local_exit(void)
 {
+        kmem_cache_destroy(_rq_bio_info_cache);
+        kmem_cache_destroy(_rq_tio_cache);
         kmem_cache_destroy(_tio_cache);
         kmem_cache_destroy(_io_cache);
         unregister_blkdev(_major, _name);
@@ -796,7 +838,11 @@ static int __split_bio(struct mapped_device *md, struct bio *bio)
         ci.map = dm_get_table(md);
         if (unlikely(!ci.map))
                 return -EIO;
-
+        if (unlikely(bio_barrier(bio) && !dm_table_barrier_ok(ci.map))) {
+                dm_table_put(ci.map);
+                bio_endio(bio, -EOPNOTSUPP);
+                return 0;
+        }
         ci.md = md;
         ci.bio = bio;
         ci.io = alloc_io(md);
@@ -880,15 +926,6 @@ static int dm_request(struct request_queue *q, struct bio *bio)
         struct mapped_device *md = q->queuedata;
         int cpu;
 
-        /*
-         * There is no use in forwarding any barrier request since we can't
-         * guarantee it is (or can be) handled by the targets correctly.
-         */
-        if (unlikely(bio_barrier(bio))) {
-                bio_endio(bio, -EOPNOTSUPP);
-                return 0;
-        }
-
         down_read(&md->io_lock);
 
         cpu = part_stat_lock();
@@ -943,8 +980,6 @@ static int dm_any_congested(void *congested_data, int bdi_bits)
         struct mapped_device *md = congested_data;
         struct dm_table *map;
 
-        atomic_inc(&md->pending);
-
         if (!test_bit(DMF_BLOCK_IO, &md->flags)) {
                 map = dm_get_table(md);
                 if (map) {
@@ -953,10 +988,6 @@ static int dm_any_congested(void *congested_data, int bdi_bits)
                 }
         }
 
-        if (!atomic_dec_return(&md->pending))
-                /* nudge anyone waiting on suspend queue */
-                wake_up(&md->wait);
-
         return r;
 }
 
@@ -1216,10 +1247,12 @@ static int __bind(struct mapped_device *md, struct dm_table *t)
 
         if (md->suspended_bdev)
                 __set_size(md, size);
-        if (size == 0)
+
+        if (!size) {
+                dm_table_destroy(t);
                 return 0;
+        }
 
-        dm_table_get(t);
         dm_table_event_callback(t, event_callback, md);
 
         write_lock(&md->map_lock);
@@ -1241,7 +1274,7 @@ static void __unbind(struct mapped_device *md)
         write_lock(&md->map_lock);
         md->map = NULL;
         write_unlock(&md->map_lock);
-        dm_table_put(map);
+        dm_table_destroy(map);
 }
 
 /*
@@ -1255,6 +1288,8 @@ int dm_create(int minor, struct mapped_device **result)
         if (!md)
                 return -ENXIO;
 
+        dm_sysfs_init(md);
+
         *result = md;
         return 0;
 }
@@ -1330,8 +1365,9 @@ void dm_put(struct mapped_device *md)
                         dm_table_presuspend_targets(map);
                         dm_table_postsuspend_targets(map);
                 }
-                __unbind(md);
+                dm_sysfs_exit(md);
                 dm_table_put(map);
+                __unbind(md);
                 free_dev(md);
         }
 }
@@ -1669,6 +1705,27 @@ struct gendisk *dm_disk(struct mapped_device *md)
         return md->disk;
 }
 
+struct kobject *dm_kobject(struct mapped_device *md)
+{
+        return &md->kobj;
+}
+
+/*
+ * struct mapped_device should not be exported outside of dm.c
+ * so use this check to verify that kobj is part of md structure
+ */
+struct mapped_device *dm_get_from_kobject(struct kobject *kobj)
+{
+        struct mapped_device *md;
+
+        md = container_of(kobj, struct mapped_device, kobj);
+        if (&md->kobj != kobj)
+                return NULL;
+
+        dm_get(md);
+        return md;
+}
+
 int dm_suspended(struct mapped_device *md)
 {
         return test_bit(DMF_SUSPENDED, &md->flags);