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-rw-r--r--fs/aio.c6
-rw-r--r--fs/autofs4/inode.c2
-rw-r--r--fs/btrfs/compression.c2
-rw-r--r--fs/btrfs/ctree.h13
-rw-r--r--fs/btrfs/dev-replace.c5
-rw-r--r--fs/btrfs/disk-io.c5
-rw-r--r--fs/btrfs/extent-tree.c148
-rw-r--r--fs/btrfs/extent_io.h1
-rw-r--r--fs/btrfs/extent_map.c2
-rw-r--r--fs/btrfs/extent_map.h1
-rw-r--r--fs/btrfs/free-space-cache.c192
-rw-r--r--fs/btrfs/inode.c41
-rw-r--r--fs/btrfs/ioctl.c37
-rw-r--r--fs/btrfs/locking.c80
-rw-r--r--fs/btrfs/print-tree.c9
-rw-r--r--fs/btrfs/raid56.c5
-rw-r--r--fs/btrfs/scrub.c19
-rw-r--r--fs/btrfs/super.c7
-rw-r--r--fs/btrfs/sysfs.c32
-rw-r--r--fs/btrfs/sysfs.h4
-rw-r--r--fs/btrfs/transaction.c12
-rw-r--r--fs/btrfs/volumes.c66
-rw-r--r--fs/btrfs/volumes.h3
-rw-r--r--fs/btrfs/zlib.c2
-rw-r--r--fs/cifs/cifs_unicode.c7
-rw-r--r--fs/cifs/cifsfs.c17
-rw-r--r--fs/cifs/link.c2
-rw-r--r--fs/ext4/balloc.c16
-rw-r--r--fs/ext4/extents_status.c4
-rw-r--r--fs/ext4/ialloc.c37
-rw-r--r--fs/ext4/indirect.c24
-rw-r--r--fs/ext4/mballoc.c12
-rw-r--r--fs/ext4/super.c60
-rw-r--r--fs/f2fs/data.c23
-rw-r--r--fs/f2fs/dir.c2
-rw-r--r--fs/f2fs/f2fs.h6
-rw-r--r--fs/f2fs/file.c12
-rw-r--r--fs/f2fs/inode.c1
-rw-r--r--fs/f2fs/namei.c13
-rw-r--r--fs/f2fs/node.c2
-rw-r--r--fs/f2fs/segment.c5
-rw-r--r--fs/f2fs/super.c4
-rw-r--r--fs/jbd2/transaction.c5
-rw-r--r--fs/kernfs/file.c69
-rw-r--r--fs/kernfs/mount.c30
-rw-r--r--fs/locks.c2
-rw-r--r--fs/mbcache.c3
-rw-r--r--fs/nfs/inode.c76
-rw-r--r--fs/nfs/nfs4_fs.h2
-rw-r--r--fs/nfs/nfs4namespace.c102
-rw-r--r--fs/nfs/nfs4proc.c2
-rw-r--r--fs/nfs/write.c4
-rw-r--r--fs/nfsd/nfs4proc.c9
-rw-r--r--fs/nfsd/nfs4state.c78
-rw-r--r--fs/nfsd/nfs4xdr.c18
-rw-r--r--fs/ocfs2/dlm/dlmcommon.h4
-rw-r--r--fs/ocfs2/dlm/dlmmaster.c57
-rw-r--r--fs/ocfs2/dlm/dlmrecovery.c3
-rw-r--r--fs/ocfs2/dlm/dlmthread.c13
-rw-r--r--fs/ocfs2/dlm/dlmunlock.c18
-rw-r--r--fs/ocfs2/namei.c145
-rw-r--r--fs/ocfs2/ocfs2_trace.h2
-rw-r--r--fs/ocfs2/refcounttree.c8
-rw-r--r--fs/ocfs2/super.c8
-rw-r--r--fs/proc/stat.c22
-rw-r--r--fs/seq_file.c30
66 files changed, 1171 insertions, 480 deletions
diff --git a/fs/aio.c b/fs/aio.c
index 4f078c054b41..955947ef3e02 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1021,6 +1021,7 @@ void aio_complete(struct kiocb *iocb, long res, long res2)
/* everything turned out well, dispose of the aiocb. */
kiocb_free(iocb);
+ put_reqs_available(ctx, 1);
/*
* We have to order our ring_info tail store above and test
@@ -1062,6 +1063,9 @@ static long aio_read_events_ring(struct kioctx *ctx,
if (head == tail)
goto out;
+ head %= ctx->nr_events;
+ tail %= ctx->nr_events;
+
while (ret < nr) {
long avail;
struct io_event *ev;
@@ -1100,8 +1104,6 @@ static long aio_read_events_ring(struct kioctx *ctx,
flush_dcache_page(ctx->ring_pages[0]);
pr_debug("%li h%u t%u\n", ret, head, tail);
-
- put_reqs_available(ctx, ret);
out:
mutex_unlock(&ctx->ring_lock);
diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
index d7bd395ab586..1c55388ae633 100644
--- a/fs/autofs4/inode.c
+++ b/fs/autofs4/inode.c
@@ -210,7 +210,7 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
int pipefd;
struct autofs_sb_info *sbi;
struct autofs_info *ino;
- int pgrp;
+ int pgrp = 0;
bool pgrp_set = false;
int ret = -EINVAL;
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 92371c414228..1daea0b47187 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -821,7 +821,7 @@ static void free_workspace(int type, struct list_head *workspace)
spin_lock(workspace_lock);
if (*num_workspace < num_online_cpus()) {
- list_add_tail(workspace, idle_workspace);
+ list_add(workspace, idle_workspace);
(*num_workspace)++;
spin_unlock(workspace_lock);
goto wake;
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index b7e2c1c1ef36..be91397f4e92 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1259,11 +1259,19 @@ struct btrfs_block_group_cache {
spinlock_t lock;
u64 pinned;
u64 reserved;
+ u64 delalloc_bytes;
u64 bytes_super;
u64 flags;
u64 sectorsize;
u64 cache_generation;
+ /*
+ * It is just used for the delayed data space allocation because
+ * only the data space allocation and the relative metadata update
+ * can be done cross the transaction.
+ */
+ struct rw_semaphore data_rwsem;
+
/* for raid56, this is a full stripe, without parity */
unsigned long full_stripe_len;
@@ -3316,7 +3324,7 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_key *ins);
int btrfs_reserve_extent(struct btrfs_root *root, u64 num_bytes,
u64 min_alloc_size, u64 empty_size, u64 hint_byte,
- struct btrfs_key *ins, int is_data);
+ struct btrfs_key *ins, int is_data, int delalloc);
int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct extent_buffer *buf, int full_backref, int no_quota);
int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
@@ -3330,7 +3338,8 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans,
u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid,
u64 owner, u64 offset, int no_quota);
-int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len);
+int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len,
+ int delalloc);
int btrfs_free_and_pin_reserved_extent(struct btrfs_root *root,
u64 start, u64 len);
void btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 2af6e66fe788..eea26e1b2fda 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -36,6 +36,7 @@
#include "check-integrity.h"
#include "rcu-string.h"
#include "dev-replace.h"
+#include "sysfs.h"
static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
int scrub_ret);
@@ -562,6 +563,10 @@ static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
fs_info->fs_devices->latest_bdev = tgt_device->bdev;
list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list);
+ /* replace the sysfs entry */
+ btrfs_kobj_rm_device(fs_info, src_device);
+ btrfs_kobj_add_device(fs_info, tgt_device);
+
btrfs_rm_dev_replace_blocked(fs_info);
btrfs_rm_dev_replace_srcdev(fs_info, src_device);
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 8bb4aa19898f..08e65e9cf2aa 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -369,7 +369,8 @@ static int verify_parent_transid(struct extent_io_tree *io_tree,
out:
unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
&cached_state, GFP_NOFS);
- btrfs_tree_read_unlock_blocking(eb);
+ if (need_lock)
+ btrfs_tree_read_unlock_blocking(eb);
return ret;
}
@@ -2904,7 +2905,9 @@ retry_root_backup:
if (ret)
goto fail_qgroup;
+ mutex_lock(&fs_info->cleaner_mutex);
ret = btrfs_recover_relocation(tree_root);
+ mutex_unlock(&fs_info->cleaner_mutex);
if (ret < 0) {
printk(KERN_WARNING
"BTRFS: failed to recover relocation\n");
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index fafb3e53ecde..813537f362f9 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -105,7 +105,8 @@ static int find_next_key(struct btrfs_path *path, int level,
static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
int dump_block_groups);
static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
- u64 num_bytes, int reserve);
+ u64 num_bytes, int reserve,
+ int delalloc);
static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
u64 num_bytes);
int btrfs_pin_extent(struct btrfs_root *root,
@@ -3260,7 +3261,8 @@ again:
spin_lock(&block_group->lock);
if (block_group->cached != BTRFS_CACHE_FINISHED ||
- !btrfs_test_opt(root, SPACE_CACHE)) {
+ !btrfs_test_opt(root, SPACE_CACHE) ||
+ block_group->delalloc_bytes) {
/*
* don't bother trying to write stuff out _if_
* a) we're not cached,
@@ -5613,6 +5615,7 @@ int btrfs_exclude_logged_extents(struct btrfs_root *log,
* @cache: The cache we are manipulating
* @num_bytes: The number of bytes in question
* @reserve: One of the reservation enums
+ * @delalloc: The blocks are allocated for the delalloc write
*
* This is called by the allocator when it reserves space, or by somebody who is
* freeing space that was never actually used on disk. For example if you
@@ -5631,7 +5634,7 @@ int btrfs_exclude_logged_extents(struct btrfs_root *log,
* succeeds.
*/
static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
- u64 num_bytes, int reserve)
+ u64 num_bytes, int reserve, int delalloc)
{
struct btrfs_space_info *space_info = cache->space_info;
int ret = 0;
@@ -5650,12 +5653,18 @@ static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
num_bytes, 0);
space_info->bytes_may_use -= num_bytes;
}
+
+ if (delalloc)
+ cache->delalloc_bytes += num_bytes;
}
} else {
if (cache->ro)
space_info->bytes_readonly += num_bytes;
cache->reserved -= num_bytes;
space_info->bytes_reserved -= num_bytes;
+
+ if (delalloc)
+ cache->delalloc_bytes -= num_bytes;
}
spin_unlock(&cache->lock);
spin_unlock(&space_info->lock);
@@ -5669,7 +5678,6 @@ void btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
struct btrfs_caching_control *next;
struct btrfs_caching_control *caching_ctl;
struct btrfs_block_group_cache *cache;
- struct btrfs_space_info *space_info;
down_write(&fs_info->commit_root_sem);
@@ -5692,9 +5700,6 @@ void btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
up_write(&fs_info->commit_root_sem);
- list_for_each_entry_rcu(space_info, &fs_info->space_info, list)
- percpu_counter_set(&space_info->total_bytes_pinned, 0);
-
update_global_block_rsv(fs_info);
}
@@ -5732,6 +5737,7 @@ static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
spin_lock(&cache->lock);
cache->pinned -= len;
space_info->bytes_pinned -= len;
+ percpu_counter_add(&space_info->total_bytes_pinned, -len);
if (cache->ro) {
space_info->bytes_readonly += len;
readonly = true;
@@ -6206,7 +6212,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
btrfs_add_free_space(cache, buf->start, buf->len);
- btrfs_update_reserved_bytes(cache, buf->len, RESERVE_FREE);
+ btrfs_update_reserved_bytes(cache, buf->len, RESERVE_FREE, 0);
trace_btrfs_reserved_extent_free(root, buf->start, buf->len);
pin = 0;
}
@@ -6365,6 +6371,70 @@ enum btrfs_loop_type {
LOOP_NO_EMPTY_SIZE = 3,
};
+static inline void
+btrfs_lock_block_group(struct btrfs_block_group_cache *cache,
+ int delalloc)
+{
+ if (delalloc)
+ down_read(&cache->data_rwsem);
+}
+
+static inline void
+btrfs_grab_block_group(struct btrfs_block_group_cache *cache,
+ int delalloc)
+{
+ btrfs_get_block_group(cache);
+ if (delalloc)
+ down_read(&cache->data_rwsem);
+}
+
+static struct btrfs_block_group_cache *
+btrfs_lock_cluster(struct btrfs_block_group_cache *block_group,
+ struct btrfs_free_cluster *cluster,
+ int delalloc)
+{
+ struct btrfs_block_group_cache *used_bg;
+ bool locked = false;
+again:
+ spin_lock(&cluster->refill_lock);
+ if (locked) {
+ if (used_bg == cluster->block_group)
+ return used_bg;
+
+ up_read(&used_bg->data_rwsem);
+ btrfs_put_block_group(used_bg);
+ }
+
+ used_bg = cluster->block_group;
+ if (!used_bg)
+ return NULL;
+
+ if (used_bg == block_group)
+ return used_bg;
+
+ btrfs_get_block_group(used_bg);
+
+ if (!delalloc)
+ return used_bg;
+
+ if (down_read_trylock(&used_bg->data_rwsem))
+ return used_bg;
+
+ spin_unlock(&cluster->refill_lock);
+ down_read(&used_bg->data_rwsem);
+ locked = true;
+ goto again;
+}
+
+static inline void
+btrfs_release_block_group(struct btrfs_block_group_cache *cache,
+ int delalloc)
+{
+ if (delalloc)
+ up_read(&cache->data_rwsem);
+ btrfs_put_block_group(cache);
+}
+
/*
* walks the btree of allocated extents and find a hole of a given size.
* The key ins is changed to record the hole:
@@ -6379,7 +6449,7 @@ enum btrfs_loop_type {
static noinline int find_free_extent(struct btrfs_root *orig_root,
u64 num_bytes, u64 empty_size,
u64 hint_byte, struct btrfs_key *ins,
- u64 flags)
+ u64 flags, int delalloc)
{
int ret = 0;
struct btrfs_root *root = orig_root->fs_info->extent_root;
@@ -6467,6 +6537,7 @@ static noinline int find_free_extent(struct btrfs_root *orig_root,
up_read(&space_info->groups_sem);
} else {
index = get_block_group_index(block_group);
+ btrfs_lock_block_group(block_group, delalloc);
goto have_block_group;
}
} else if (block_group) {
@@ -6481,7 +6552,7 @@ search:
u64 offset;
int cached;
- btrfs_get_block_group(block_group);
+ btrfs_grab_block_group(block_group, delalloc);
search_start = block_group->key.objectid;
/*
@@ -6529,16 +6600,16 @@ have_block_group:
* the refill lock keeps out other
* people trying to start a new cluster
*/
- spin_lock(&last_ptr->refill_lock);
- used_block_group = last_ptr->block_group;
- if (used_block_group != block_group &&
- (!used_block_group ||
- used_block_group->ro ||
- !block_group_bits(used_block_group, flags)))
+ used_block_group = btrfs_lock_cluster(block_group,
+ last_ptr,
+ delalloc);
+ if (!used_block_group)
goto refill_cluster;
- if (used_block_group != block_group)
- btrfs_get_block_group(used_block_group);
+ if (used_block_group != block_group &&
+ (used_block_group->ro ||
+ !block_group_bits(used_block_group, flags)))
+ goto release_cluster;
offset = btrfs_alloc_from_cluster(used_block_group,
last_ptr,
@@ -6552,16 +6623,15 @@ have_block_group:
used_block_group,
search_start, num_bytes);
if (used_block_group != block_group) {
- btrfs_put_block_group(block_group);
+ btrfs_release_block_group(block_group,
+ delalloc);
block_group = used_block_group;
}
goto checks;
}
WARN_ON(last_ptr->block_group != used_block_group);
- if (used_block_group != block_group)
- btrfs_put_block_group(used_block_group);
-refill_cluster:
+release_cluster:
/* If we are on LOOP_NO_EMPTY_SIZE, we can't
* set up a new clusters, so lets just skip it
* and let the allocator find whatever block
@@ -6578,8 +6648,10 @@ refill_cluster:
* succeeding in the unclustered
* allocation. */
if (loop >= LOOP_NO_EMPTY_SIZE &&
- last_ptr->block_group != block_group) {
+ used_block_group != block_group) {
spin_unlock(&last_ptr->refill_lock);
+ btrfs_release_block_group(used_block_group,
+ delalloc);
goto unclustered_alloc;
}
@@ -6589,6 +6661,10 @@ refill_cluster:
*/
btrfs_return_cluster_to_free_space(NULL, last_ptr);
+ if (used_block_group != block_group)
+ btrfs_release_block_group(used_block_group,
+ delalloc);
+refill_cluster:
if (loop >= LOOP_NO_EMPTY_SIZE) {
spin_unlock(&last_ptr->refill_lock);
goto unclustered_alloc;
@@ -6696,7 +6772,7 @@ checks:
BUG_ON(offset > search_start);
ret = btrfs_update_reserved_bytes(block_group, num_bytes,
- alloc_type);
+ alloc_type, delalloc);
if (ret == -EAGAIN) {
btrfs_add_free_space(block_group, offset, num_bytes);
goto loop;
@@ -6708,13 +6784,13 @@ checks:
trace_btrfs_reserve_extent(orig_root, block_group,
search_start, num_bytes);
- btrfs_put_block_group(block_group);
+ btrfs_release_block_group(block_group, delalloc);
break;
loop:
failed_cluster_refill = false;
failed_alloc = false;
BUG_ON(index != get_block_group_index(block_group));
- btrfs_put_block_group(block_group);
+ btrfs_release_block_group(block_group, delalloc);
}
up_read(&space_info->groups_sem);
@@ -6827,7 +6903,7 @@ again:
int btrfs_reserve_extent(struct btrfs_root *root,
u64 num_bytes, u64 min_alloc_size,
u64 empty_size, u64 hint_byte,
- struct btrfs_key *ins, int is_data)
+ struct btrfs_key *ins, int is_data, int delalloc)
{
bool final_tried = false;
u64 flags;
@@ -6837,7 +6913,7 @@ int btrfs_reserve_extent(struct btrfs_root *root,
again:
WARN_ON(num_bytes < root->sectorsize);
ret = find_free_extent(root, num_bytes, empty_size, hint_byte, ins,
- flags);
+ flags, delalloc);
if (ret == -ENOSPC) {
if (!final_tried && ins->offset) {
@@ -6862,7 +6938,8 @@ again:
}
static int __btrfs_free_reserved_extent(struct btrfs_root *root,
- u64 start, u64 len, int pin)
+ u64 start, u64 len,
+ int pin, int delalloc)
{
struct btrfs_block_group_cache *cache;
int ret = 0;
@@ -6881,7 +6958,7 @@ static int __btrfs_free_reserved_extent(struct btrfs_root *root,
pin_down_extent(root, cache, start, len, 1);
else {
btrfs_add_free_space(cache, start, len);
- btrfs_update_reserved_bytes(cache, len, RESERVE_FREE);
+ btrfs_update_reserved_bytes(cache, len, RESERVE_FREE, delalloc);
}
btrfs_put_block_group(cache);
@@ -6891,15 +6968,15 @@ static int __btrfs_free_reserved_extent(struct btrfs_root *root,
}
int btrfs_free_reserved_extent(struct btrfs_root *root,
- u64 start, u64 len)
+ u64 start, u64 len, int delalloc)
{
- return __btrfs_free_reserved_extent(root, start, len, 0);
+ return __btrfs_free_reserved_extent(root, start, len, 0, delalloc);
}
int btrfs_free_and_pin_reserved_extent(struct btrfs_root *root,
u64 start, u64 len)
{
- return __btrfs_free_reserved_extent(root, start, len, 1);
+ return __btrfs_free_reserved_extent(root, start, len, 1, 0);
}
static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
@@ -7114,7 +7191,7 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
return -EINVAL;
ret = btrfs_update_reserved_bytes(block_group, ins->offset,
- RESERVE_ALLOC_NO_ACCOUNT);
+ RESERVE_ALLOC_NO_ACCOUNT, 0);
BUG_ON(ret); /* logic error */
ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
0, owner, offset, ins, 1);
@@ -7256,7 +7333,7 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
return ERR_CAST(block_rsv);
ret = btrfs_reserve_extent(root, blocksize, blocksize,
- empty_size, hint, &ins, 0);
+ empty_size, hint, &ins, 0, 0);
if (ret) {
unuse_block_rsv(root->fs_info, block_rsv, blocksize);
return ERR_PTR(ret);
@@ -8659,6 +8736,7 @@ btrfs_create_block_group_cache(struct btrfs_root *root, u64 start, u64 size)
start);
atomic_set(&cache->count, 1);
spin_lock_init(&cache->lock);
+ init_rwsem(&cache->data_rwsem);
INIT_LIST_HEAD(&cache->list);
INIT_LIST_HEAD(&cache->cluster_list);
INIT_LIST_HEAD(&cache->new_bg_list);
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 15ce5f2a2b62..ccc264e7bde1 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -158,7 +158,6 @@ struct extent_buffer {
* to unlock
*/
wait_queue_head_t read_lock_wq;
- wait_queue_head_t lock_wq;
struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
#ifdef CONFIG_BTRFS_DEBUG
struct list_head leak_list;
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 1874aee69c86..225302b39afb 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -75,6 +75,8 @@ void free_extent_map(struct extent_map *em)
if (atomic_dec_and_test(&em->refs)) {
WARN_ON(extent_map_in_tree(em));