Merge branches 'sched/clock', 'sched/cleanups' and 'linus' into sched/urgent

[linux-2.6-omap-h63xx.git] / drivers / md / dm.c

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 343094c3feeb834c55f8aa1ecd3baa57890eca1d..51ba1db4b3e7e7abf59d6b183fc610e8bdc0db04 100644 (file)
--- 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;
 }
 
@@ -1093,7 +1124,7 @@ static struct mapped_device *alloc_dev(int minor)
        if (!md->tio_pool)
                goto bad_tio_pool;
 
-       md->bs = bioset_create(16, 16);
+       md->bs = bioset_create(16, 0);
        if (!md->bs)
                goto bad_no_bioset;
 
@@ -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);