1 files changed, 66 insertions, 119 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 9489a2aca47b..e0b7bb92a170 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -830,7 +830,6 @@ out:
 
 /*
  * find_free_dev_extent - find free space in the specified device
- * @trans:      transaction handler
  * @device:     the device which we search the free space in
  * @num_bytes:  the size of the free space that we need
  * @start:      store the start of the free space.
@@ -849,8 +848,7 @@ out:
  * But if we don't find suitable free space, it is used to store the size of
  * the max free space.
  */
-int find_free_dev_extent(struct btrfs_trans_handle *trans,
-                         struct btrfs_device *device, u64 num_bytes,
+int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
                          u64 *start, u64 *len)
 {
         struct btrfs_key key;
@@ -894,7 +892,7 @@ int find_free_dev_extent(struct btrfs_trans_handle *trans,
         key.offset = search_start;
         key.type = BTRFS_DEV_EXTENT_KEY;
 
-        ret = btrfs_search_slot(trans, root, &key, path, 0, 0);
+        ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
         if (ret < 0)
                 goto out;
         if (ret > 0) {
@@ -1468,8 +1466,7 @@ error_undo:
 /*
  * does all the dirty work required for changing file system's UUID.
  */
-static int btrfs_prepare_sprout(struct btrfs_trans_handle *trans,
-                                struct btrfs_root *root)
+static int btrfs_prepare_sprout(struct btrfs_root *root)
 {
         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
         struct btrfs_fs_devices *old_devices;
@@ -1693,7 +1690,7 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
 
         if (seeding_dev) {
                 sb->s_flags &= ~MS_RDONLY;
-                ret = btrfs_prepare_sprout(trans, root);
+                ret = btrfs_prepare_sprout(root);
                 BUG_ON(ret);
         }
 
@@ -3044,8 +3041,7 @@ done:
         return ret;
 }
 
-static int btrfs_add_system_chunk(struct btrfs_trans_handle *trans,
-                           struct btrfs_root *root,
+static int btrfs_add_system_chunk(struct btrfs_root *root,
                            struct btrfs_key *key,
                            struct btrfs_chunk *chunk, int item_size)
 {
@@ -3221,7 +3217,7 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
                 if (total_avail == 0)
                         continue;
 
-                ret = find_free_dev_extent(trans, device,
+                ret = find_free_dev_extent(device,
                                            max_stripe_size * dev_stripes,
                                            &dev_offset, &max_avail);
                 if (ret && ret != -ENOSPC)
@@ -3412,7 +3408,7 @@ static int __finish_chunk_alloc(struct btrfs_trans_handle *trans,
         BUG_ON(ret);
 
         if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
-                ret = btrfs_add_system_chunk(trans, chunk_root, &key, chunk,
+                ret = btrfs_add_system_chunk(chunk_root, &key, chunk,
                                              item_size);
                 BUG_ON(ret);
         }
@@ -3624,26 +3620,13 @@ static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
         u64 stripe_nr;
         u64 stripe_nr_orig;
         u64 stripe_nr_end;
-        int stripes_allocated = 8;
-        int stripes_required = 1;
         int stripe_index;
         int i;
+        int ret = 0;
         int num_stripes;
         int max_errors = 0;
         struct btrfs_bio *bbio = NULL;
 
-        if (bbio_ret && !(rw & (REQ_WRITE | REQ_DISCARD)))
-                stripes_allocated = 1;
-again:
-        if (bbio_ret) {
-                bbio = kzalloc(btrfs_bio_size(stripes_allocated),
-                                GFP_NOFS);
-                if (!bbio)
-                        return -ENOMEM;
-
-                atomic_set(&bbio->error, 0);
-        }
-
         read_lock(&em_tree->lock);
         em = lookup_extent_mapping(em_tree, logical, *length);
         read_unlock(&em_tree->lock);
@@ -3662,28 +3645,6 @@ again:
         if (mirror_num > map->num_stripes)
                 mirror_num = 0;
 
-        /* if our btrfs_bio struct is too small, back off and try again */
-        if (rw & REQ_WRITE) {
-                if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
-                                 BTRFS_BLOCK_GROUP_DUP)) {
-                        stripes_required = map->num_stripes;
-                        max_errors = 1;
-                } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
-                        stripes_required = map->sub_stripes;
-                        max_errors = 1;
-                }
-        }
-        if (rw & REQ_DISCARD) {
-                if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK)
-                        stripes_required = map->num_stripes;
-        }
-        if (bbio_ret && (rw & (REQ_WRITE | REQ_DISCARD)) &&
-            stripes_allocated < stripes_required) {
-                stripes_allocated = map->num_stripes;
-                free_extent_map(em);
-                kfree(bbio);
-                goto again;
-        }
         stripe_nr = offset;
         /*
          * stripe_nr counts the total number of stripes we have to stride
@@ -3775,81 +3736,55 @@ again:
         }
         BUG_ON(stripe_index >= map->num_stripes);
 
+        bbio = kzalloc(btrfs_bio_size(num_stripes), GFP_NOFS);
+        if (!bbio) {
+                ret = -ENOMEM;
+                goto out;
+        }
+        atomic_set(&bbio->error, 0);
+
         if (rw & REQ_DISCARD) {
+                int factor = 0;
+                int sub_stripes = 0;
+                u64 stripes_per_dev = 0;
+                u32 remaining_stripes = 0;
+
+                if (map->type &
+                    (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) {
+                        if (map->type & BTRFS_BLOCK_GROUP_RAID0)
+                                sub_stripes = 1;
+                        else
+                                sub_stripes = map->sub_stripes;
+
+                        factor = map->num_stripes / sub_stripes;
+                        stripes_per_dev = div_u64_rem(stripe_nr_end -
+                                                      stripe_nr_orig,
+                                                      factor,
+                                                      &remaining_stripes);
+                }
+
                 for (i = 0; i < num_stripes; i++) {
                         bbio->stripes[i].physical =
                                 map->stripes[stripe_index].physical +
                                 stripe_offset + stripe_nr * map->stripe_len;
                         bbio->stripes[i].dev = map->stripes[stripe_index].dev;
 
-                        if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
-                                u64 stripes;
-                                u32 last_stripe = 0;
-                                int j;
-
-                                div_u64_rem(stripe_nr_end - 1,
-                                            map->num_stripes,
-                                            &last_stripe);
-
-                                for (j = 0; j < map->num_stripes; j++) {
-                                        u32 test;
-
-                                        div_u64_rem(stripe_nr_end - 1 - j,
-                                                    map->num_stripes, &test);
-                                        if (test == stripe_index)
-                                                break;
-                                }
-                                stripes = stripe_nr_end - 1 - j;
-                                do_div(stripes, map->num_stripes);
-                                bbio->stripes[i].length = map->stripe_len *
-                                        (stripes - stripe_nr + 1);
-
-                                if (i == 0) {
-                                        bbio->stripes[i].length -=
-                                                stripe_offset;
-                                        stripe_offset = 0;
-                                }
-                                if (stripe_index == last_stripe)
-                                        bbio->stripes[i].length -=
-                                                stripe_end_offset;
-                        } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
-                                u64 stripes;
-                                int j;
-                                int factor = map->num_stripes /
-                                             map->sub_stripes;
-                                u32 last_stripe = 0;
-
-                                div_u64_rem(stripe_nr_end - 1,
-                                            factor, &last_stripe);
-                                last_stripe *= map->sub_stripes;
-
-                                for (j = 0; j < factor; j++) {
-                                        u32 test;
-
-                                        div_u64_rem(stripe_nr_end - 1 - j,
-                                                    factor, &test);
-
-                                        if (test ==
-                                            stripe_index / map->sub_stripes)
-                                                break;
-                                }
-                                stripes = stripe_nr_end - 1 - j;
-                                do_div(stripes, factor);
-                                bbio->stripes[i].length = map->stripe_len *
-                                        (stripes - stripe_nr + 1);
-
-                                if (i < map->sub_stripes) {
+                        if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
+                                         BTRFS_BLOCK_GROUP_RAID10)) {
+                                bbio->stripes[i].length = stripes_per_dev *
+                                                          map->stripe_len;
+                                if (i / sub_stripes < remaining_stripes)
+                                        bbio->stripes[i].length +=
+                                                map->stripe_len;
+                                if (i < sub_stripes)
                                         bbio->stripes[i].length -=
                                                 stripe_offset;
-                                        if (i == map->sub_stripes - 1)
-                                                stripe_offset = 0;
-                                }
-                                if (stripe_index >= last_stripe &&
-                                    stripe_index <= (last_stripe +
-                                                     map->sub_stripes - 1)) {
+                                if ((i / sub_stripes + 1) %
+                                    sub_stripes == remaining_stripes)
                                         bbio->stripes[i].length -=
                                                 stripe_end_offset;
-                                }
+                                if (i == sub_stripes - 1)
+                                        stripe_offset = 0;
                         } else
                                 bbio->stripes[i].length = *length;
 
@@ -3871,15 +3806,22 @@ again:
                         stripe_index++;
                 }
         }
-        if (bbio_ret) {
-                *bbio_ret = bbio;
-                bbio->num_stripes = num_stripes;
-                bbio->max_errors = max_errors;
-                bbio->mirror_num = mirror_num;
+
+        if (rw & REQ_WRITE) {
+                if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
+                                 BTRFS_BLOCK_GROUP_RAID10 |
+                                 BTRFS_BLOCK_GROUP_DUP)) {
+                        max_errors = 1;
+                }
         }
+
+        *bbio_ret = bbio;
+        bbio->num_stripes = num_stripes;
+        bbio->max_errors = max_errors;
+        bbio->mirror_num = mirror_num;
 out:
         free_extent_map(em);
-        return 0;
+        return ret;
 }
 
 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
@@ -4284,7 +4226,7 @@ static int open_seed_devices(struct btrfs_root *root, u8 *fsid)
         struct btrfs_fs_devices *fs_devices;
         int ret;
 
-        mutex_lock(&uuid_mutex);
+        BUG_ON(!mutex_is_locked(&uuid_mutex));
 
         fs_devices = root->fs_info->fs_devices->seed;
         while (fs_devices) {
@@ -4322,7 +4264,6 @@ static int open_seed_devices(struct btrfs_root *root, u8 *fsid)
         fs_devices->seed = root->fs_info->fs_devices->seed;
         root->fs_info->fs_devices->seed = fs_devices;
 out:
-        mutex_unlock(&uuid_mutex);
         return ret;
 }
 
@@ -4465,6 +4406,9 @@ int btrfs_read_chunk_tree(struct btrfs_root *root)
         if (!path)
                 return -ENOMEM;
 
+        mutex_lock(&uuid_mutex);
+        lock_chunks(root);
+
         /* first we search for all of the device items, and then we
          * read in all of the chunk items.  This way we can create chunk
          * mappings that reference all of the devices that are afound
@@ -4515,6 +4459,9 @@ again:
         }
         ret = 0;
 error:
+        unlock_chunks(root);
+        mutex_unlock(&uuid_mutex);
+
         btrfs_free_path(path);
         return ret;
 }