kexec jump: __ftrace_enabled_save/restore

[linux-2.6] / drivers / md / dm.c

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 6617ce4af09579285a2be1090adde8c9f61a3fb4..bca448e118786a78a5e07b54f3cb3a7e3aca85d5 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -37,8 +37,8 @@ static DEFINE_SPINLOCK(_minor_lock);
 struct dm_io {
        struct mapped_device *md;
        int error;
-       struct bio *bio;
        atomic_t io_count;
+       struct bio *bio;
        unsigned long start_time;
 };
 
@@ -204,6 +204,7 @@ static int (*_inits[])(void) __initdata = {
        dm_target_init,
        dm_linear_init,
        dm_stripe_init,
+       dm_kcopyd_init,
        dm_interface_init,
 };
 
@@ -212,6 +213,7 @@ static void (*_exits[])(void) = {
        dm_target_exit,
        dm_linear_exit,
        dm_stripe_exit,
+       dm_kcopyd_exit,
        dm_interface_exit,
 };
 
@@ -827,6 +829,49 @@ static int __split_bio(struct mapped_device *md, struct bio *bio)
  * CRUD END
  *---------------------------------------------------------------*/
 
+static int dm_merge_bvec(struct request_queue *q,
+                        struct bvec_merge_data *bvm,
+                        struct bio_vec *biovec)
+{
+       struct mapped_device *md = q->queuedata;
+       struct dm_table *map = dm_get_table(md);
+       struct dm_target *ti;
+       sector_t max_sectors;
+       int max_size;
+
+       if (unlikely(!map))
+               return 0;
+
+       ti = dm_table_find_target(map, bvm->bi_sector);
+
+       /*
+        * Find maximum amount of I/O that won't need splitting
+        */
+       max_sectors = min(max_io_len(md, bvm->bi_sector, ti),
+                         (sector_t) BIO_MAX_SECTORS);
+       max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size;
+       if (max_size < 0)
+               max_size = 0;
+
+       /*
+        * merge_bvec_fn() returns number of bytes
+        * it can accept at this offset
+        * max is precomputed maximal io size
+        */
+       if (max_size && ti->type->merge)
+               max_size = ti->type->merge(ti, bvm, biovec, max_size);
+
+       /*
+        * Always allow an entire first page
+        */
+       if (max_size <= biovec->bv_len && !(bvm->bi_size >> SECTOR_SHIFT))
+               max_size = biovec->bv_len;
+
+       dm_table_put(map);
+
+       return max_size;
+}
+
 /*
  * The request function that just remaps the bio built up by
  * dm_merge_bvec.
@@ -922,7 +967,7 @@ static void free_minor(int minor)
 /*
  * See if the device with a specific minor # is free.
  */
-static int specific_minor(struct mapped_device *md, int minor)
+static int specific_minor(int minor)
 {
        int r, m;
 
@@ -955,7 +1000,7 @@ out:
        return r;
 }
 
-static int next_free_minor(struct mapped_device *md, int *minor)
+static int next_free_minor(int *minor)
 {
        int r, m;
 
@@ -966,9 +1011,8 @@ static int next_free_minor(struct mapped_device *md, int *minor)
        spin_lock(&_minor_lock);
 
        r = idr_get_new(&_minor_idr, MINOR_ALLOCED, &m);
-       if (r) {
+       if (r)
                goto out;
-       }
 
        if (m >= (1 << MINORBITS)) {
                idr_remove(&_minor_idr, m);
@@ -991,7 +1035,7 @@ static struct block_device_operations dm_blk_dops;
 static struct mapped_device *alloc_dev(int minor)
 {
        int r;
-       struct mapped_device *md = kmalloc(sizeof(*md), GFP_KERNEL);
+       struct mapped_device *md = kzalloc(sizeof(*md), GFP_KERNEL);
        void *old_md;
 
        if (!md) {
@@ -1004,13 +1048,12 @@ static struct mapped_device *alloc_dev(int minor)
 
        /* get a minor number for the dev */
        if (minor == DM_ANY_MINOR)
-               r = next_free_minor(md, &minor);
+               r = next_free_minor(&minor);
        else
-               r = specific_minor(md, minor);
+               r = specific_minor(minor);
        if (r < 0)
                goto bad_minor;
 
-       memset(md, 0, sizeof(*md));
        init_rwsem(&md->io_lock);
        mutex_init(&md->suspend_lock);
        spin_lock_init(&md->pushback_lock);
@@ -1032,6 +1075,7 @@ static struct mapped_device *alloc_dev(int minor)
        blk_queue_make_request(md->queue, dm_request);
        blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY);
        md->queue->unplug_fn = dm_unplug_all;
+       blk_queue_merge_bvec(md->queue, dm_merge_bvec);
 
        md->io_pool = mempool_create_slab_pool(MIN_IOS, _io_cache);
        if (!md->io_pool)