[PATCH 00/11] btrfs: move the space_info code out of extent-tree.c

[PATCH 00/11] btrfs: move the space_info code out of extent-tree.c

[Josef Bacik]

This is the first pass at making extent-tree.c much smaller.  I've purposefully
done no other cleanups or changes.  The places where I needed to modify callers
were done in separate patches.  The only time I moved and changed callers in
large chunks was the moving of reserve_metadata_bytes out of extent-tree.c, and
that was just to rename the users of reserve_metadata_bytes to
btrfs_reserve_metadata_bytes.

There is 0 functional change in this series.  The next step is to move the other
space reservation code that is specific to delayed_refs, inodes, etc.  But I
wanted to start with this to make sure we're all onboard with this approach
before I do other things.

The diffstat for the whole series is the following

 fs/btrfs/Makefile           |    2 +-
 fs/btrfs/ctree.h            |   97 +---
 fs/btrfs/extent-tree.c      | 1277 +++----------------------------------------
 fs/btrfs/free-space-cache.c |    1 +
 fs/btrfs/ioctl.c            |    1 +
 fs/btrfs/space-info.c       | 1103 +++++++++++++++++++++++++++++++++++++
 fs/btrfs/space-info.h       |  135 +++++
 fs/btrfs/super.c            |    1 +
 fs/btrfs/sysfs.c            |    1 +
 fs/btrfs/volumes.c          |    1 +
 10 files changed, 1343 insertions(+), 1276 deletions(-)

Thanks,

Josef

[PATCH 01/11] btrfs: move space_info to space_info.h

[Josef Bacik]

Migrate the struct definition and the one helper that's in ctree.h into
space_info.h

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/ctree.h            | 73 +---------------------------------------
 fs/btrfs/extent-tree.c      |  1 +
 fs/btrfs/free-space-cache.c |  1 +
 fs/btrfs/ioctl.c            |  1 +
 fs/btrfs/space-info.h       | 81 +++++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/super.c            |  1 +
 fs/btrfs/sysfs.c            |  1 +
 fs/btrfs/volumes.c          |  1 +
 8 files changed, 88 insertions(+), 72 deletions(-)
 create mode 100644 fs/btrfs/space-info.h

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 47ab5b1ff7d8..0936db74d3e3 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -37,6 +37,7 @@ struct btrfs_trans_handle;
 struct btrfs_transaction;
 struct btrfs_pending_snapshot;
 struct btrfs_delayed_ref_root;
+struct btrfs_space_info;
 extern struct kmem_cache *btrfs_trans_handle_cachep;
 extern struct kmem_cache *btrfs_bit_radix_cachep;
 extern struct kmem_cache *btrfs_path_cachep;
@@ -393,72 +394,6 @@ struct raid_kobject {
 	struct list_head list;
 };
 
-struct btrfs_space_info {
-	spinlock_t lock;
-
-	u64 total_bytes;	/* total bytes in the space,
-				   this doesn't take mirrors into account */
-	u64 bytes_used;		/* total bytes used,
-				   this doesn't take mirrors into account */
-	u64 bytes_pinned;	/* total bytes pinned, will be freed when the
-				   transaction finishes */
-	u64 bytes_reserved;	/* total bytes the allocator has reserved for
-				   current allocations */
-	u64 bytes_may_use;	/* number of bytes that may be used for
-				   delalloc/allocations */
-	u64 bytes_readonly;	/* total bytes that are read only */
-
-	u64 max_extent_size;	/* This will hold the maximum extent size of
-				   the space info if we had an ENOSPC in the
-				   allocator. */
-
-	unsigned int full:1;	/* indicates that we cannot allocate any more
-				   chunks for this space */
-	unsigned int chunk_alloc:1;	/* set if we are allocating a chunk */
-
-	unsigned int flush:1;		/* set if we are trying to make space */
-
-	unsigned int force_alloc;	/* set if we need to force a chunk
-					   alloc for this space */
-
-	u64 disk_used;		/* total bytes used on disk */
-	u64 disk_total;		/* total bytes on disk, takes mirrors into
-				   account */
-
-	u64 flags;
-
-	/*
-	 * bytes_pinned is kept in line with what is actually pinned, as in
-	 * we've called update_block_group and dropped the bytes_used counter
-	 * and increased the bytes_pinned counter.  However this means that
-	 * bytes_pinned does not reflect the bytes that will be pinned once the
-	 * delayed refs are flushed, so this counter is inc'ed every time we
-	 * call btrfs_free_extent so it is a realtime count of what will be
-	 * freed once the transaction is committed.  It will be zeroed every
-	 * time the transaction commits.
-	 */
-	struct percpu_counter total_bytes_pinned;
-
-	struct list_head list;
-	/* Protected by the spinlock 'lock'. */
-	struct list_head ro_bgs;
-	struct list_head priority_tickets;
-	struct list_head tickets;
-	/*
-	 * tickets_id just indicates the next ticket will be handled, so note
-	 * it's not stored per ticket.
-	 */
-	u64 tickets_id;
-
-	struct rw_semaphore groups_sem;
-	/* for block groups in our same type */
-	struct list_head block_groups[BTRFS_NR_RAID_TYPES];
-	wait_queue_head_t wait;
-
-	struct kobject kobj;
-	struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
-};
-
 /*
  * Types of block reserves
  */
@@ -2677,12 +2612,6 @@ static inline u64 btrfs_extref_hash(u64 parent_objectid, const char *name,
        return (u64) crc32c(parent_objectid, name, len);
 }
 
-static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
-{
-	return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
-		(space_info->flags & BTRFS_BLOCK_GROUP_DATA));
-}
-
 static inline gfp_t btrfs_alloc_write_mask(struct address_space *mapping)
 {
 	return mapping_gfp_constraint(mapping, ~__GFP_FS);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 396edca9b31f..fbd173ebc4be 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -28,6 +28,7 @@
 #include "sysfs.h"
 #include "qgroup.h"
 #include "ref-verify.h"
+#include "space-info.h"
 
 #undef SCRAMBLE_DELAYED_REFS
 
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 6814fa42eba3..390cd3d7d5ea 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -18,6 +18,7 @@
 #include "extent_io.h"
 #include "inode-map.h"
 #include "volumes.h"
+#include "space-info.h"
 
 #define BITS_PER_BITMAP		(PAGE_SIZE * 8UL)
 #define MAX_CACHE_BYTES_PER_GIG	SZ_32K
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 803577d42518..1af3af3d708c 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -43,6 +43,7 @@
 #include "qgroup.h"
 #include "tree-log.h"
 #include "compression.h"
+#include "space-info.h"
 
 #ifdef CONFIG_64BIT
 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
new file mode 100644
index 000000000000..2f69cf9e13da
--- /dev/null
+++ b/fs/btrfs/space-info.h
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Facebook.  All rights reserved.
+ */
+
+#ifndef BTRFS_SPACE_INFO_H
+#define BTRFS_SPACE_INFO_H
+
+struct btrfs_space_info {
+	spinlock_t lock;
+
+	u64 total_bytes;	/* total bytes in the space,
+				   this doesn't take mirrors into account */
+	u64 bytes_used;		/* total bytes used,
+				   this doesn't take mirrors into account */
+	u64 bytes_pinned;	/* total bytes pinned, will be freed when the
+				   transaction finishes */
+	u64 bytes_reserved;	/* total bytes the allocator has reserved for
+				   current allocations */
+	u64 bytes_may_use;	/* number of bytes that may be used for
+				   delalloc/allocations */
+	u64 bytes_readonly;	/* total bytes that are read only */
+
+	u64 max_extent_size;	/* This will hold the maximum extent size of
+				   the space info if we had an ENOSPC in the
+				   allocator. */
+
+	unsigned int full:1;	/* indicates that we cannot allocate any more
+				   chunks for this space */
+	unsigned int chunk_alloc:1;	/* set if we are allocating a chunk */
+
+	unsigned int flush:1;		/* set if we are trying to make space */
+
+	unsigned int force_alloc;	/* set if we need to force a chunk
+					   alloc for this space */
+
+	u64 disk_used;		/* total bytes used on disk */
+	u64 disk_total;		/* total bytes on disk, takes mirrors into
+				   account */
+
+	u64 flags;
+
+	/*
+	 * bytes_pinned is kept in line with what is actually pinned, as in
+	 * we've called update_block_group and dropped the bytes_used counter
+	 * and increased the bytes_pinned counter.  However this means that
+	 * bytes_pinned does not reflect the bytes that will be pinned once the
+	 * delayed refs are flushed, so this counter is inc'ed every time we
+	 * call btrfs_free_extent so it is a realtime count of what will be
+	 * freed once the transaction is committed.  It will be zeroed every
+	 * time the transaction commits.
+	 */
+	struct percpu_counter total_bytes_pinned;
+
+	struct list_head list;
+	/* Protected by the spinlock 'lock'. */
+	struct list_head ro_bgs;
+	struct list_head priority_tickets;
+	struct list_head tickets;
+	/*
+	 * tickets_id just indicates the next ticket will be handled, so note
+	 * it's not stored per ticket.
+	 */
+	u64 tickets_id;
+
+	struct rw_semaphore groups_sem;
+	/* for block groups in our same type */
+	struct list_head block_groups[BTRFS_NR_RAID_TYPES];
+	wait_queue_head_t wait;
+
+	struct kobject kobj;
+	struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
+};
+
+static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
+{
+	return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
+		(space_info->flags & BTRFS_BLOCK_GROUP_DATA));
+}
+
+#endif /* BTRFS_SPACE_INFO_H */
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 72998695e302..267f74b2ea8b 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -42,6 +42,7 @@
 #include "dev-replace.h"
 #include "free-space-cache.h"
 #include "backref.h"
+#include "space-info.h"
 #include "tests/btrfs-tests.h"
 
 #include "qgroup.h"
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index 2f078b77fe14..e6493b068294 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -16,6 +16,7 @@
 #include "transaction.h"
 #include "sysfs.h"
 #include "volumes.h"
+#include "space-info.h"
 
 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
 static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 9cbeec2bfbf9..68bc894ec48e 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -28,6 +28,7 @@
 #include "dev-replace.h"
 #include "sysfs.h"
 #include "tree-checker.h"
+#include "space-info.h"
 
 const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
 	[BTRFS_RAID_RAID10] = {
-- 
2.14.3

[PATCH 02/11] btrfs: rename do_chunk_alloc to btrfs_chunk_alloc

[Josef Bacik]

Really we just need the enum, but as we break more things up it'll help
to have this external to extent-tree.c.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/ctree.h       | 22 ++++++++++++++++++++++
 fs/btrfs/extent-tree.c | 50 ++++++++++++++------------------------------------
 2 files changed, 36 insertions(+), 36 deletions(-)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 0936db74d3e3..cceb1b5fab33 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2764,6 +2764,28 @@ enum btrfs_flush_state {
 	COMMIT_TRANS		=	9,
 };
 
+/*
+ * control flags for do_chunk_alloc's force field
+ * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
+ * if we really need one.
+ *
+ * CHUNK_ALLOC_LIMITED means to only try and allocate one
+ * if we have very few chunks already allocated.  This is
+ * used as part of the clustering code to help make sure
+ * we have a good pool of storage to cluster in, without
+ * filling the FS with empty chunks
+ *
+ * CHUNK_ALLOC_FORCE means it must try to allocate one
+ *
+ */
+enum btrfs_chunk_alloc_enum {
+	CHUNK_ALLOC_NO_FORCE = 0,
+	CHUNK_ALLOC_LIMITED = 1,
+	CHUNK_ALLOC_FORCE = 2,
+};
+
+int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
+		      enum btrfs_chunk_alloc_enum force);
 int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes);
 int btrfs_check_data_free_space(struct inode *inode,
 			struct extent_changeset **reserved, u64 start, u64 len);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index fbd173ebc4be..7b4232ee48a0 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -32,26 +32,6 @@
 
 #undef SCRAMBLE_DELAYED_REFS
 
-/*
- * control flags for do_chunk_alloc's force field
- * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
- * if we really need one.
- *
- * CHUNK_ALLOC_LIMITED means to only try and allocate one
- * if we have very few chunks already allocated.  This is
- * used as part of the clustering code to help make sure
- * we have a good pool of storage to cluster in, without
- * filling the FS with empty chunks
- *
- * CHUNK_ALLOC_FORCE means it must try to allocate one
- *
- */
-enum {
-	CHUNK_ALLOC_NO_FORCE = 0,
-	CHUNK_ALLOC_LIMITED = 1,
-	CHUNK_ALLOC_FORCE = 2,
-};
-
 /*
  * Declare a helper function to detect underflow of various space info members
  */
@@ -88,8 +68,6 @@ static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
 				     struct btrfs_delayed_ref_node *node,
 				     struct btrfs_delayed_extent_op *extent_op);
-static int do_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
-			  int force);
 static int find_next_key(struct btrfs_path *path, int level,
 			 struct btrfs_key *key);
 static void dump_space_info(struct btrfs_fs_info *fs_info,
@@ -4143,8 +4121,8 @@ int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes)
 			if (IS_ERR(trans))
 				return PTR_ERR(trans);
 
-			ret = do_chunk_alloc(trans, alloc_target,
-					     CHUNK_ALLOC_NO_FORCE);
+			ret = btrfs_chunk_alloc(trans, alloc_target,
+						CHUNK_ALLOC_NO_FORCE);
 			btrfs_end_transaction(trans);
 			if (ret < 0) {
 				if (ret != -ENOSPC)
@@ -4414,8 +4392,8 @@ void check_system_chunk(struct btrfs_trans_handle *trans, u64 type)
  *    - return 1 if it successfully allocates a chunk,
  *    - return errors including -ENOSPC otherwise.
  */
-static int do_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
-			  int force)
+int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
+		      enum btrfs_chunk_alloc_enum force)
 {
 	struct btrfs_fs_info *fs_info = trans->fs_info;
 	struct btrfs_space_info *space_info;
@@ -4879,10 +4857,10 @@ static void flush_space(struct btrfs_fs_info *fs_info,
 			ret = PTR_ERR(trans);
 			break;
 		}
-		ret = do_chunk_alloc(trans,
-				     btrfs_metadata_alloc_profile(fs_info),
-				     (state == ALLOC_CHUNK) ?
-				      CHUNK_ALLOC_NO_FORCE : CHUNK_ALLOC_FORCE);
+		ret = btrfs_chunk_alloc(trans,
+				btrfs_metadata_alloc_profile(fs_info),
+				(state == ALLOC_CHUNK) ? CHUNK_ALLOC_NO_FORCE :
+					CHUNK_ALLOC_FORCE);
 		btrfs_end_transaction(trans);
 		if (ret > 0 || ret == -ENOSPC)
 			ret = 0;
@@ -7674,8 +7652,8 @@ static int find_free_extent_update_loop(struct btrfs_fs_info *fs_info,
 				return ret;
 			}
 
-			ret = do_chunk_alloc(trans, ffe_ctl->flags,
-					     CHUNK_ALLOC_FORCE);
+			ret = btrfs_chunk_alloc(trans, ffe_ctl->flags,
+						CHUNK_ALLOC_FORCE);
 
 			/*
 			 * If we can't allocate a new chunk we've already looped
@@ -9691,8 +9669,8 @@ int btrfs_inc_block_group_ro(struct btrfs_block_group_cache *cache)
 	 */
 	alloc_flags = update_block_group_flags(fs_info, cache->flags);
 	if (alloc_flags != cache->flags) {
-		ret = do_chunk_alloc(trans, alloc_flags,
-				     CHUNK_ALLOC_FORCE);
+		ret = btrfs_chunk_alloc(trans, alloc_flags,
+					CHUNK_ALLOC_FORCE);
 		/*
 		 * ENOSPC is allowed here, we may have enough space
 		 * already allocated at the new raid level to
@@ -9708,7 +9686,7 @@ int btrfs_inc_block_group_ro(struct btrfs_block_group_cache *cache)
 	if (!ret)
 		goto out;
 	alloc_flags = get_alloc_profile(fs_info, cache->space_info->flags);
-	ret = do_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
+	ret = btrfs_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
 	if (ret < 0)
 		goto out;
 	ret = inc_block_group_ro(cache, 0);
@@ -9729,7 +9707,7 @@ int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type)
 {
 	u64 alloc_flags = get_alloc_profile(trans->fs_info, type);
 
-	return do_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
+	return btrfs_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
 }
 
 /*
-- 
2.14.3

[PATCH 03/11] btrfs: export space_info_add_*_bytes

[Josef Bacik]

Prep work for consolidating all of the space_info code into one file.
We need to export these so multiple files can use them.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/extent-tree.c | 42 ++++++++++++++++++++----------------------
 fs/btrfs/space-info.h  |  6 ++++++
 2 files changed, 26 insertions(+), 22 deletions(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 7b4232ee48a0..9dcda96ef309 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -75,12 +75,6 @@ static void dump_space_info(struct btrfs_fs_info *fs_info,
 			    int dump_block_groups);
 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
 			       u64 num_bytes);
-static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
-				     struct btrfs_space_info *space_info,
-				     u64 num_bytes);
-static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
-				     struct btrfs_space_info *space_info,
-				     u64 num_bytes);
 
 static noinline int
 block_group_cache_done(struct btrfs_block_group_cache *cache)
@@ -3908,8 +3902,8 @@ static void update_space_info(struct btrfs_fs_info *info, u64 flags,
 	found->bytes_readonly += bytes_readonly;
 	if (total_bytes > 0)
 		found->full = 0;
-	space_info_add_new_bytes(info, found, total_bytes -
-				 bytes_used - bytes_readonly);
+	btrfs_space_info_add_new_bytes(info, found, total_bytes -
+				       bytes_used - bytes_readonly);
 	spin_unlock(&found->lock);
 	*space_info = found;
 }
@@ -5110,7 +5104,8 @@ static int wait_reserve_ticket(struct btrfs_fs_info *fs_info,
 	spin_unlock(&space_info->lock);
 
 	if (reclaim_bytes)
-		space_info_add_old_bytes(fs_info, space_info, reclaim_bytes);
+		btrfs_space_info_add_old_bytes(fs_info, space_info,
+					       reclaim_bytes);
 	return ret;
 }
 
@@ -5227,7 +5222,8 @@ static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
 	spin_unlock(&space_info->lock);
 
 	if (reclaim_bytes)
-		space_info_add_old_bytes(fs_info, space_info, reclaim_bytes);
+		btrfs_space_info_add_old_bytes(fs_info, space_info,
+					       reclaim_bytes);
 	ASSERT(list_empty(&ticket.list));
 	return ret;
 }
@@ -5393,8 +5389,9 @@ void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info,
 		trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
 					      0, num_bytes, 1);
 	if (to_free)
-		space_info_add_old_bytes(fs_info, delayed_refs_rsv->space_info,
-					 to_free);
+		btrfs_space_info_add_old_bytes(fs_info,
+					       delayed_refs_rsv->space_info,
+					       to_free);
 }
 
 /**
@@ -5437,9 +5434,9 @@ int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
  * This is for space we already have accounted in space_info->bytes_may_use, so
  * basically when we're returning space from block_rsv's.
  */
-static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
-				     struct btrfs_space_info *space_info,
-				     u64 num_bytes)
+void btrfs_space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_space_info *space_info,
+				    u64 num_bytes)
 {
 	struct reserve_ticket *ticket;
 	struct list_head *head;
@@ -5497,9 +5494,9 @@ static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
  * space_info->bytes_may_use yet.  So if we allocate a chunk or unpin an extent
  * we use this helper.
  */
-static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
-				     struct btrfs_space_info *space_info,
-				     u64 num_bytes)
+void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_space_info *space_info,
+				    u64 num_bytes)
 {
 	struct reserve_ticket *ticket;
 	struct list_head *head = &space_info->priority_tickets;
@@ -5583,8 +5580,8 @@ static u64 block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
 			spin_unlock(&dest->lock);
 		}
 		if (num_bytes)
-			space_info_add_old_bytes(fs_info, space_info,
-						 num_bytes);
+			btrfs_space_info_add_old_bytes(fs_info, space_info,
+						       num_bytes);
 	}
 	if (qgroup_to_release_ret)
 		*qgroup_to_release_ret = qgroup_to_release;
@@ -6760,8 +6757,9 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info,
 			spin_unlock(&global_rsv->lock);
 			/* Add to any tickets we may have */
 			if (len)
-				space_info_add_new_bytes(fs_info, space_info,
-							 len);
+				btrfs_space_info_add_new_bytes(fs_info,
+							       space_info,
+							       len);
 		}
 		spin_unlock(&space_info->lock);
 	}
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
index 2f69cf9e13da..b3a43fe62b7c 100644
--- a/fs/btrfs/space-info.h
+++ b/fs/btrfs/space-info.h
@@ -78,4 +78,10 @@ static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
 		(space_info->flags & BTRFS_BLOCK_GROUP_DATA));
 }
 
+void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_space_info *space_info,
+				    u64 num_bytes);
+void btrfs_space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_space_info *space_info,
+				    u64 num_bytes);
 #endif /* BTRFS_SPACE_INFO_H */
-- 
2.14.3

[PATCH 04/11] btrfs: move the space_info handling code to space-info.c

[Josef Bacik]

These are the basic init and lookup functions and some helper functions,
fairly straightforward before the bad stuff starts.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/Makefile      |   2 +-
 fs/btrfs/extent-tree.c | 205 +++++--------------------------------------------
 fs/btrfs/space-info.c  | 177 ++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/space-info.h  |  11 +++
 4 files changed, 208 insertions(+), 187 deletions(-)
 create mode 100644 fs/btrfs/space-info.c

diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index ca693dd554e9..ae5fad57bc9c 100644
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -10,7 +10,7 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
 	   export.o tree-log.o free-space-cache.o zlib.o lzo.o zstd.o \
 	   compression.o delayed-ref.o relocation.o delayed-inode.o scrub.o \
 	   reada.o backref.o ulist.o qgroup.o send.o dev-replace.o raid56.o \
-	   uuid-tree.o props.o free-space-tree.o tree-checker.o
+	   uuid-tree.o props.o free-space-tree.o tree-checker.o space-info.o
 
 btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o
 btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 9dcda96ef309..a30d265fee5e 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -713,25 +713,6 @@ struct btrfs_block_group_cache *btrfs_lookup_block_group(
 	return block_group_cache_tree_search(info, bytenr, 1);
 }
 
-static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
-						  u64 flags)
-{
-	struct list_head *head = &info->space_info;
-	struct btrfs_space_info *found;
-
-	flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(found, head, list) {
-		if (found->flags & flags) {
-			rcu_read_unlock();
-			return found;
-		}
-	}
-	rcu_read_unlock();
-	return NULL;
-}
-
 static u64 generic_ref_to_space_flags(struct btrfs_ref *ref)
 {
 	if (ref->type == BTRFS_REF_METADATA) {
@@ -749,7 +730,7 @@ static void add_pinned_bytes(struct btrfs_fs_info *fs_info,
 	struct btrfs_space_info *space_info;
 	u64 flags = generic_ref_to_space_flags(ref);
 
-	space_info = __find_space_info(fs_info, flags);
+	space_info = btrfs_find_space_info(fs_info, flags);
 	ASSERT(space_info);
 	percpu_counter_add_batch(&space_info->total_bytes_pinned, ref->len,
 		    BTRFS_TOTAL_BYTES_PINNED_BATCH);
@@ -761,27 +742,12 @@ static void sub_pinned_bytes(struct btrfs_fs_info *fs_info,
 	struct btrfs_space_info *space_info;
 	u64 flags = generic_ref_to_space_flags(ref);
 
-	space_info = __find_space_info(fs_info, flags);
+	space_info = btrfs_find_space_info(fs_info, flags);
 	ASSERT(space_info);
 	percpu_counter_add_batch(&space_info->total_bytes_pinned, -ref->len,
 		    BTRFS_TOTAL_BYTES_PINNED_BATCH);
 }
 
-/*
- * after adding space to the filesystem, we need to clear the full flags
- * on all the space infos.
- */
-void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
-{
-	struct list_head *head = &info->space_info;
-	struct btrfs_space_info *found;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(found, head, list)
-		found->full = 0;
-	rcu_read_unlock();
-}
-
 /* simple helper to search for an existing data extent at a given offset */
 int btrfs_lookup_data_extent(struct btrfs_fs_info *fs_info, u64 start, u64 len)
 {
@@ -2449,7 +2415,7 @@ void btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info *fs_info,
 			flags = BTRFS_BLOCK_GROUP_SYSTEM;
 		else
 			flags = BTRFS_BLOCK_GROUP_METADATA;
-		space_info = __find_space_info(fs_info, flags);
+		space_info = btrfs_find_space_info(fs_info, flags);
 		ASSERT(space_info);
 		percpu_counter_add_batch(&space_info->total_bytes_pinned,
 				   -head->num_bytes,
@@ -3821,93 +3787,6 @@ void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg)
 	wait_var_event(&bg->nocow_writers, !atomic_read(&bg->nocow_writers));
 }
 
-static const char *alloc_name(u64 flags)
-{
-	switch (flags) {
-	case BTRFS_BLOCK_GROUP_METADATA|BTRFS_BLOCK_GROUP_DATA:
-		return "mixed";
-	case BTRFS_BLOCK_GROUP_METADATA:
-		return "metadata";
-	case BTRFS_BLOCK_GROUP_DATA:
-		return "data";
-	case BTRFS_BLOCK_GROUP_SYSTEM:
-		return "system";
-	default:
-		WARN_ON(1);
-		return "invalid-combination";
-	};
-}
-
-static int create_space_info(struct btrfs_fs_info *info, u64 flags)
-{
-
-	struct btrfs_space_info *space_info;
-	int i;
-	int ret;
-
-	space_info = kzalloc(sizeof(*space_info), GFP_NOFS);
-	if (!space_info)
-		return -ENOMEM;
-
-	ret = percpu_counter_init(&space_info->total_bytes_pinned, 0,
-				 GFP_KERNEL);
-	if (ret) {
-		kfree(space_info);
-		return ret;
-	}
-
-	for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
-		INIT_LIST_HEAD(&space_info->block_groups[i]);
-	init_rwsem(&space_info->groups_sem);
-	spin_lock_init(&space_info->lock);
-	space_info->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
-	space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
-	init_waitqueue_head(&space_info->wait);
-	INIT_LIST_HEAD(&space_info->ro_bgs);
-	INIT_LIST_HEAD(&space_info->tickets);
-	INIT_LIST_HEAD(&space_info->priority_tickets);
-
-	ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
-				    info->space_info_kobj, "%s",
-				    alloc_name(space_info->flags));
-	if (ret) {
-		kobject_put(&space_info->kobj);
-		return ret;
-	}
-
-	list_add_rcu(&space_info->list, &info->space_info);
-	if (flags & BTRFS_BLOCK_GROUP_DATA)
-		info->data_sinfo = space_info;
-
-	return ret;
-}
-
-static void update_space_info(struct btrfs_fs_info *info, u64 flags,
-			     u64 total_bytes, u64 bytes_used,
-			     u64 bytes_readonly,
-			     struct btrfs_space_info **space_info)
-{
-	struct btrfs_space_info *found;
-	int factor;
-
-	factor = btrfs_bg_type_to_factor(flags);
-
-	found = __find_space_info(info, flags);
-	ASSERT(found);
-	spin_lock(&found->lock);
-	found->total_bytes += total_bytes;
-	found->disk_total += total_bytes * factor;
-	found->bytes_used += bytes_used;
-	found->disk_used += bytes_used * factor;
-	found->bytes_readonly += bytes_readonly;
-	if (total_bytes > 0)
-		found->full = 0;
-	btrfs_space_info_add_new_bytes(info, found, total_bytes -
-				       bytes_used - bytes_readonly);
-	spin_unlock(&found->lock);
-	*space_info = found;
-}
-
 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
 {
 	u64 extra_flags = chunk_to_extended(flags) &
@@ -4055,15 +3934,6 @@ u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info)
 	return get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
 }
 
-static u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
-				 bool may_use_included)
-{
-	ASSERT(s_info);
-	return s_info->bytes_used + s_info->bytes_reserved +
-		s_info->bytes_pinned + s_info->bytes_readonly +
-		(may_use_included ? s_info->bytes_may_use : 0);
-}
-
 int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes)
 {
 	struct btrfs_root *root = inode->root;
@@ -4339,7 +4209,7 @@ void check_system_chunk(struct btrfs_trans_handle *trans, u64 type)
 	 */
 	lockdep_assert_held(&fs_info->chunk_mutex);
 
-	info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
+	info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
 	spin_lock(&info->lock);
 	left = info->total_bytes - btrfs_space_info_used(info, true);
 	spin_unlock(&info->lock);
@@ -4400,7 +4270,7 @@ int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
 	if (trans->allocating_chunk)
 		return -ENOSPC;
 
-	space_info = __find_space_info(fs_info, flags);
+	space_info = btrfs_find_space_info(fs_info, flags);
 	ASSERT(space_info);
 
 	do {
@@ -4629,7 +4499,7 @@ static void shrink_delalloc(struct btrfs_fs_info *fs_info, u64 to_reclaim,
 	to_reclaim = items * EXTENT_SIZE_PER_ITEM;
 
 	trans = (struct btrfs_trans_handle *)current->journal_info;
-	space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
+	space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
 
 	delalloc_bytes = percpu_counter_sum_positive(
 						&fs_info->delalloc_bytes);
@@ -4967,7 +4837,7 @@ static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
 	u64 last_tickets_id;
 
 	fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work);
-	space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
+	space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
 
 	spin_lock(&space_info->lock);
 	to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
@@ -5614,7 +5484,7 @@ void btrfs_init_metadata_block_rsv(struct btrfs_fs_info *fs_info,
 				   unsigned short type)
 {
 	btrfs_init_block_rsv(rsv, type);
-	rsv->space_info = __find_space_info(fs_info,
+	rsv->space_info = btrfs_find_space_info(fs_info,
 					    BTRFS_BLOCK_GROUP_METADATA);
 }
 
@@ -5839,10 +5709,10 @@ static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
 {
 	struct btrfs_space_info *space_info;
 
-	space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
+	space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
 	fs_info->chunk_block_rsv.space_info = space_info;
 
-	space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
+	space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
 	fs_info->global_block_rsv.space_info = space_info;
 	fs_info->trans_block_rsv.space_info = space_info;
 	fs_info->empty_block_rsv.space_info = space_info;
@@ -5951,7 +5821,7 @@ int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
 	}
 
 	num_bytes = btrfs_calc_trans_metadata_size(fs_info, items);
-	rsv->space_info = __find_space_info(fs_info,
+	rsv->space_info = btrfs_find_space_info(fs_info,
 					    BTRFS_BLOCK_GROUP_METADATA);
 	ret = btrfs_block_rsv_add(root, rsv, num_bytes,
 				  BTRFS_RESERVE_FLUSH_ALL);
@@ -7747,7 +7617,7 @@ static noinline int find_free_extent(struct btrfs_fs_info *fs_info,
 
 	trace_find_free_extent(fs_info, num_bytes, empty_size, flags);
 
-	space_info = __find_space_info(fs_info, flags);
+	space_info = btrfs_find_space_info(fs_info, flags);
 	if (!space_info) {
 		btrfs_err(fs_info, "No space info for %llu", flags);
 		return -ENOSPC;
@@ -8102,7 +7972,7 @@ int btrfs_reserve_extent(struct btrfs_root *root, u64 ram_bytes,
 		} else if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
 			struct btrfs_space_info *sinfo;
 
-			sinfo = __find_space_info(fs_info, flags);
+			sinfo = btrfs_find_space_info(fs_info, flags);
 			btrfs_err(fs_info,
 				  "allocation failed flags %llu, wanted %llu",
 				  flags, num_bytes);
@@ -10137,7 +10007,7 @@ void btrfs_add_raid_kobjects(struct btrfs_fs_info *fs_info)
 	spin_unlock(&fs_info->pending_raid_kobjs_lock);
 
 	list_for_each_entry(rkobj, &list, list) {
-		space_info = __find_space_info(fs_info, rkobj->flags);
+		space_info = btrfs_find_space_info(fs_info, rkobj->flags);
 
 		ret = kobject_add(&rkobj->kobj, &space_info->kobj,
 				"%s", btrfs_bg_type_to_raid_name(rkobj->flags));
@@ -10404,9 +10274,9 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info)
 		}
 
 		trace_btrfs_add_block_group(info, cache, 0);
-		update_space_info(info, cache->flags, found_key.offset,
-				  btrfs_block_group_used(&cache->item),
-				  cache->bytes_super, &space_info);
+		btrfs_update_space_info(info, cache->flags, found_key.offset,
+					btrfs_block_group_used(&cache->item),
+					cache->bytes_super, &space_info);
 
 		cache->space_info = space_info;
 
@@ -10541,7 +10411,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used,
 	 * assigned to our block group. We want our bg to be added to the rbtree
 	 * with its ->space_info set.
 	 */
-	cache->space_info = __find_space_info(fs_info, cache->flags);
+	cache->space_info = btrfs_find_space_info(fs_info, cache->flags);
 	ASSERT(cache->space_info);
 
 	ret = btrfs_add_block_group_cache(fs_info, cache);
@@ -10556,7 +10426,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used,
 	 * the rbtree, update the space info's counters.
 	 */
 	trace_btrfs_add_block_group(fs_info, cache, 1);
-	update_space_info(fs_info, cache->flags, size, bytes_used,
+	btrfs_update_space_info(fs_info, cache->flags, size, bytes_used,
 				cache->bytes_super, &cache->space_info);
 	update_global_block_rsv(fs_info);
 
@@ -11061,43 +10931,6 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
 	spin_unlock(&fs_info->unused_bgs_lock);
 }
 
-int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
-{
-	struct btrfs_super_block *disk_super;
-	u64 features;
-	u64 flags;
-	int mixed = 0;
-	int ret;
-
-	disk_super = fs_info->super_copy;
-	if (!btrfs_super_root(disk_super))
-		return -EINVAL;
-
-	features = btrfs_super_incompat_flags(disk_super);
-	if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
-		mixed = 1;
-
-	flags = BTRFS_BLOCK_GROUP_SYSTEM;
-	ret = create_space_info(fs_info, flags);
-	if (ret)
-		goto out;
-
-	if (mixed) {
-		flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
-		ret = create_space_info(fs_info, flags);
-	} else {
-		flags = BTRFS_BLOCK_GROUP_METADATA;
-		ret = create_space_info(fs_info, flags);
-		if (ret)
-			goto out;
-
-		flags = BTRFS_BLOCK_GROUP_DATA;
-		ret = create_space_info(fs_info, flags);
-	}
-out:
-	return ret;
-}
-
 int btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info,
 				   u64 start, u64 end)
 {
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
new file mode 100644
index 000000000000..348b57055d77
--- /dev/null
+++ b/fs/btrfs/space-info.c
@@ -0,0 +1,177 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Facebook.  All rights reserved.
+ */
+
+#include "ctree.h"
+#include "space-info.h"
+#include "sysfs.h"
+#include "volumes.h"
+
+u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
+			  bool may_use_included)
+{
+	ASSERT(s_info);
+	return s_info->bytes_used + s_info->bytes_reserved +
+		s_info->bytes_pinned + s_info->bytes_readonly +
+		(may_use_included ? s_info->bytes_may_use : 0);
+}
+
+/*
+ * after adding space to the filesystem, we need to clear the full flags
+ * on all the space infos.
+ */
+void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
+{
+	struct list_head *head = &info->space_info;
+	struct btrfs_space_info *found;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(found, head, list)
+		found->full = 0;
+	rcu_read_unlock();
+}
+
+static const char *alloc_name(u64 flags)
+{
+	switch (flags) {
+	case BTRFS_BLOCK_GROUP_METADATA|BTRFS_BLOCK_GROUP_DATA:
+		return "mixed";
+	case BTRFS_BLOCK_GROUP_METADATA:
+		return "metadata";
+	case BTRFS_BLOCK_GROUP_DATA:
+		return "data";
+	case BTRFS_BLOCK_GROUP_SYSTEM:
+		return "system";
+	default:
+		WARN_ON(1);
+		return "invalid-combination";
+	};
+}
+
+static int create_space_info(struct btrfs_fs_info *info, u64 flags)
+{
+
+	struct btrfs_space_info *space_info;
+	int i;
+	int ret;
+
+	space_info = kzalloc(sizeof(*space_info), GFP_NOFS);
+	if (!space_info)
+		return -ENOMEM;
+
+	ret = percpu_counter_init(&space_info->total_bytes_pinned, 0,
+				 GFP_KERNEL);
+	if (ret) {
+		kfree(space_info);
+		return ret;
+	}
+
+	for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
+		INIT_LIST_HEAD(&space_info->block_groups[i]);
+	init_rwsem(&space_info->groups_sem);
+	spin_lock_init(&space_info->lock);
+	space_info->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
+	space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
+	init_waitqueue_head(&space_info->wait);
+	INIT_LIST_HEAD(&space_info->ro_bgs);
+	INIT_LIST_HEAD(&space_info->tickets);
+	INIT_LIST_HEAD(&space_info->priority_tickets);
+
+	ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
+				    info->space_info_kobj, "%s",
+				    alloc_name(space_info->flags));
+	if (ret) {
+		kobject_put(&space_info->kobj);
+		return ret;
+	}
+
+	list_add_rcu(&space_info->list, &info->space_info);
+	if (flags & BTRFS_BLOCK_GROUP_DATA)
+		info->data_sinfo = space_info;
+
+	return ret;
+}
+
+int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
+{
+	struct btrfs_super_block *disk_super;
+	u64 features;
+	u64 flags;
+	int mixed = 0;
+	int ret;
+
+	disk_super = fs_info->super_copy;
+	if (!btrfs_super_root(disk_super))
+		return -EINVAL;
+
+	features = btrfs_super_incompat_flags(disk_super);
+	if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
+		mixed = 1;
+
+	flags = BTRFS_BLOCK_GROUP_SYSTEM;
+	ret = create_space_info(fs_info, flags);
+	if (ret)
+		goto out;
+
+	if (mixed) {
+		flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
+		ret = create_space_info(fs_info, flags);
+	} else {
+		flags = BTRFS_BLOCK_GROUP_METADATA;
+		ret = create_space_info(fs_info, flags);
+		if (ret)
+			goto out;
+
+		flags = BTRFS_BLOCK_GROUP_DATA;
+		ret = create_space_info(fs_info, flags);
+	}
+out:
+	return ret;
+}
+
+void btrfs_update_space_info(struct btrfs_fs_info *info, u64 flags,
+			     u64 total_bytes, u64 bytes_used,
+			     u64 bytes_readonly,
+			     struct btrfs_space_info **space_info)
+{
+	struct btrfs_space_info *found;
+	int factor;
+
+	factor = btrfs_bg_type_to_factor(flags);
+
+	found = btrfs_find_space_info(info, flags);
+	ASSERT(found);
+	spin_lock(&found->lock);
+	found->total_bytes += total_bytes;
+	found->disk_total += total_bytes * factor;
+	found->bytes_used += bytes_used;
+	found->disk_used += bytes_used * factor;
+	found->bytes_readonly += bytes_readonly;
+	if (total_bytes > 0)
+		found->full = 0;
+	btrfs_space_info_add_new_bytes(info, found,
+				       total_bytes - bytes_used -
+				       bytes_readonly);
+	spin_unlock(&found->lock);
+	*space_info = found;
+}
+
+struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
+					       u64 flags)
+{
+	struct list_head *head = &info->space_info;
+	struct btrfs_space_info *found;
+
+	flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(found, head, list) {
+		if (found->flags & flags) {
+			rcu_read_unlock();
+			return found;
+		}
+	}
+	rcu_read_unlock();
+	return NULL;
+}
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
index b3a43fe62b7c..a5a228b59806 100644
--- a/fs/btrfs/space-info.h
+++ b/fs/btrfs/space-info.h
@@ -84,4 +84,15 @@ void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
 void btrfs_space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
 				    struct btrfs_space_info *space_info,
 				    u64 num_bytes);
+int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
+void btrfs_update_space_info(struct btrfs_fs_info *info, u64 flags,
+			     u64 total_bytes, u64 bytes_used,
+			     u64 bytes_readonly,
+			     struct btrfs_space_info **space_info);
+struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
+					       u64 flags);
+u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
+			  bool may_use_included);
+void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
+
 #endif /* BTRFS_SPACE_INFO_H */
-- 
2.14.3

[PATCH 05/11] btrfs: move and export can_overcommit

[Josef Bacik]

This is the first piece of moving the space reservation code to
space-info.c

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/extent-tree.c | 83 +++++---------------------------------------------
 fs/btrfs/space-info.c  | 68 +++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/space-info.h  |  4 +++
 3 files changed, 80 insertions(+), 75 deletions(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index a30d265fee5e..6eebfa5df53c 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4147,11 +4147,6 @@ static void force_metadata_allocation(struct btrfs_fs_info *info)
 	rcu_read_unlock();
 }
 
-static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)
-{
-	return (global->size << 1);
-}
-
 static int should_alloc_chunk(struct btrfs_fs_info *fs_info,
 			      struct btrfs_space_info *sinfo, int force)
 {
@@ -4378,69 +4373,6 @@ int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
 	return ret;
 }
 
-static int can_overcommit(struct btrfs_fs_info *fs_info,
-			  struct btrfs_space_info *space_info, u64 bytes,
-			  enum btrfs_reserve_flush_enum flush,
-			  bool system_chunk)
-{
-	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
-	u64 profile;
-	u64 space_size;
-	u64 avail;
-	u64 used;
-	int factor;
-
-	/* Don't overcommit when in mixed mode. */
-	if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)
-		return 0;
-
-	if (system_chunk)
-		profile = btrfs_system_alloc_profile(fs_info);
-	else
-		profile = btrfs_metadata_alloc_profile(fs_info);
-
-	used = btrfs_space_info_used(space_info, false);
-
-	/*
-	 * We only want to allow over committing if we have lots of actual space
-	 * free, but if we don't have enough space to handle the global reserve
-	 * space then we could end up having a real enospc problem when trying
-	 * to allocate a chunk or some other such important allocation.
-	 */
-	spin_lock(&global_rsv->lock);
-	space_size = calc_global_rsv_need_space(global_rsv);
-	spin_unlock(&global_rsv->lock);
-	if (used + space_size >= space_info->total_bytes)
-		return 0;
-
-	used += space_info->bytes_may_use;
-
-	avail = atomic64_read(&fs_info->free_chunk_space);
-
-	/*
-	 * If we have dup, raid1 or raid10 then only half of the free
-	 * space is actually usable.  For raid56, the space info used
-	 * doesn't include the parity drive, so we don't have to
-	 * change the math
-	 */
-	factor = btrfs_bg_type_to_factor(profile);
-	avail = div_u64(avail, factor);
-
-	/*
-	 * If we aren't flushing all things, let us overcommit up to
-	 * 1/2th of the space. If we can flush, don't let us overcommit
-	 * too much, let it overcommit up to 1/8 of the space.
-	 */
-	if (flush == BTRFS_RESERVE_FLUSH_ALL)
-		avail >>= 3;
-	else
-		avail >>= 1;
-
-	if (used + bytes < space_info->total_bytes + avail)
-		return 1;
-	return 0;
-}
-
 static void btrfs_writeback_inodes_sb_nr(struct btrfs_fs_info *fs_info,
 					 unsigned long nr_pages, int nr_items)
 {
@@ -4768,14 +4700,14 @@ btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info,
 		return to_reclaim;
 
 	to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M);
-	if (can_overcommit(fs_info, space_info, to_reclaim,
-			   BTRFS_RESERVE_FLUSH_ALL, system_chunk))
+	if (btrfs_can_overcommit(fs_info, space_info, to_reclaim,
+				 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
 		return 0;
 
 	used = btrfs_space_info_used(space_info, true);
 
-	if (can_overcommit(fs_info, space_info, SZ_1M,
-			   BTRFS_RESERVE_FLUSH_ALL, system_chunk))
+	if (btrfs_can_overcommit(fs_info, space_info, SZ_1M,
+				 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
 		expected = div_factor_fine(space_info->total_bytes, 95);
 	else
 		expected = div_factor_fine(space_info->total_bytes, 90);
@@ -5021,8 +4953,8 @@ static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
 		trace_btrfs_space_reservation(fs_info, "space_info",
 					      space_info->flags, orig_bytes, 1);
 		ret = 0;
-	} else if (can_overcommit(fs_info, space_info, orig_bytes, flush,
-				  system_chunk)) {
+	} else if (btrfs_can_overcommit(fs_info, space_info, orig_bytes, flush,
+					system_chunk)) {
 		update_bytes_may_use(fs_info, space_info, orig_bytes);
 		trace_btrfs_space_reservation(fs_info, "space_info",
 					      space_info->flags, orig_bytes, 1);
@@ -5334,7 +5266,8 @@ void btrfs_space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
 		 * adding the ticket space would be a double count.
 		 */
 		if (check_overcommit &&
-		    !can_overcommit(fs_info, space_info, 0, flush, false))
+		    !btrfs_can_overcommit(fs_info, space_info, 0, flush,
+					  false))
 			break;
 		if (num_bytes >= ticket->bytes) {
 			list_del_init(&ticket->list);
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index 348b57055d77..2cb9f3b6ffc9 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -175,3 +175,71 @@ struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
 	rcu_read_unlock();
 	return NULL;
 }
+
+static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)
+{
+	return (global->size << 1);
+}
+
+int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
+			 struct btrfs_space_info *space_info, u64 bytes,
+			 enum btrfs_reserve_flush_enum flush,
+			 bool system_chunk)
+{
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+	u64 profile;
+	u64 space_size;
+	u64 avail;
+	u64 used;
+	int factor;
+
+	/* Don't overcommit when in mixed mode. */
+	if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)
+		return 0;
+
+	if (system_chunk)
+		profile = btrfs_system_alloc_profile(fs_info);
+	else
+		profile = btrfs_metadata_alloc_profile(fs_info);
+
+	used = btrfs_space_info_used(space_info, false);
+
+	/*
+	 * We only want to allow over committing if we have lots of actual space
+	 * free, but if we don't have enough space to handle the global reserve
+	 * space then we could end up having a real enospc problem when trying
+	 * to allocate a chunk or some other such important allocation.
+	 */
+	spin_lock(&global_rsv->lock);
+	space_size = calc_global_rsv_need_space(global_rsv);
+	spin_unlock(&global_rsv->lock);
+	if (used + space_size >= space_info->total_bytes)
+		return 0;
+
+	used += space_info->bytes_may_use;
+
+	avail = atomic64_read(&fs_info->free_chunk_space);
+
+	/*
+	 * If we have dup, raid1 or raid10 then only half of the free
+	 * space is actually usable.  For raid56, the space info used
+	 * doesn't include the parity drive, so we don't have to
+	 * change the math
+	 */
+	factor = btrfs_bg_type_to_factor(profile);
+	avail = div_u64(avail, factor);
+
+	/*
+	 * If we aren't flushing all things, let us overcommit up to
+	 * 1/2th of the space. If we can flush, don't let us overcommit
+	 * too much, let it overcommit up to 1/8 of the space.
+	 */
+	if (flush == BTRFS_RESERVE_FLUSH_ALL)
+		avail >>= 3;
+	else
+		avail >>= 1;
+
+	if (used + bytes < space_info->total_bytes + avail)
+		return 1;
+	return 0;
+}
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
index a5a228b59806..c1f48f548cb6 100644
--- a/fs/btrfs/space-info.h
+++ b/fs/btrfs/space-info.h
@@ -94,5 +94,9 @@ struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
 u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
 			  bool may_use_included);
 void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
+int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
+			 struct btrfs_space_info *space_info, u64 bytes,
+			 enum btrfs_reserve_flush_enum flush,
+			 bool system_chunk);
 
 #endif /* BTRFS_SPACE_INFO_H */
-- 
2.14.3

[PATCH 06/11] btrfs: move the space info update macro to space-info.h

[Josef Bacik]

Also rename it to btrfs_space_info_update_* so it's clear what we're
updating.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/extent-tree.c | 68 +++++++++++++++++++++++---------------------------
 fs/btrfs/space-info.h  | 22 ++++++++++++++++
 2 files changed, 53 insertions(+), 37 deletions(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 6eebfa5df53c..4ed194f4f60f 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -32,26 +32,6 @@
 
 #undef SCRAMBLE_DELAYED_REFS
 
-/*
- * Declare a helper function to detect underflow of various space info members
- */
-#define DECLARE_SPACE_INFO_UPDATE(name)					\
-static inline void update_##name(struct btrfs_fs_info *fs_info,		\
-				 struct btrfs_space_info *sinfo,	\
-				 s64 bytes)				\
-{									\
-	lockdep_assert_held(&sinfo->lock);				\
-	trace_update_##name(fs_info, sinfo, sinfo->name, bytes);	\
-	if (bytes < 0 && sinfo->name < -bytes) {			\
-		WARN_ON(1);						\
-		sinfo->name = 0;					\
-		return;							\
-	}								\
-	sinfo->name += bytes;						\
-}
-
-DECLARE_SPACE_INFO_UPDATE(bytes_may_use);
-DECLARE_SPACE_INFO_UPDATE(bytes_pinned);
 
 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 			       struct btrfs_delayed_ref_node *node, u64 parent,
@@ -4054,7 +4034,7 @@ int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes)
 					      data_sinfo->flags, bytes, 1);
 		return -ENOSPC;
 	}
-	update_bytes_may_use(fs_info, data_sinfo, bytes);
+	btrfs_space_info_update_bytes_may_use(fs_info, data_sinfo, bytes);
 	trace_btrfs_space_reservation(fs_info, "space_info",
 				      data_sinfo->flags, bytes, 1);
 	spin_unlock(&data_sinfo->lock);
@@ -4107,7 +4087,7 @@ void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
 
 	data_sinfo = fs_info->data_sinfo;
 	spin_lock(&data_sinfo->lock);
-	update_bytes_may_use(fs_info, data_sinfo, -len);
+	btrfs_space_info_update_bytes_may_use(fs_info, data_sinfo, -len);
 	trace_btrfs_space_reservation(fs_info, "space_info",
 				      data_sinfo->flags, len, 0);
 	spin_unlock(&data_sinfo->lock);
@@ -4949,13 +4929,15 @@ static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
 	 * If not things get more complicated.
 	 */
 	if (used + orig_bytes <= space_info->total_bytes) {
-		update_bytes_may_use(fs_info, space_info, orig_bytes);
+		btrfs_space_info_update_bytes_may_use(fs_info, space_info,
+						      orig_bytes);
 		trace_btrfs_space_reservation(fs_info, "space_info",
 					      space_info->flags, orig_bytes, 1);
 		ret = 0;
 	} else if (btrfs_can_overcommit(fs_info, space_info, orig_bytes, flush,
 					system_chunk)) {
-		update_bytes_may_use(fs_info, space_info, orig_bytes);
+		btrfs_space_info_update_bytes_may_use(fs_info, space_info,
+						      orig_bytes);
 		trace_btrfs_space_reservation(fs_info, "space_info",
 					      space_info->flags, orig_bytes, 1);
 		ret = 0;
@@ -5286,7 +5268,7 @@ void btrfs_space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
 		flush = BTRFS_RESERVE_FLUSH_ALL;
 		goto again;
 	}
-	update_bytes_may_use(fs_info, space_info, -num_bytes);
+	btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
 	trace_btrfs_space_reservation(fs_info, "space_info",
 				      space_info->flags, num_bytes, 0);
 	spin_unlock(&space_info->lock);
@@ -5314,8 +5296,9 @@ void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
 						      ticket->bytes, 1);
 			list_del_init(&ticket->list);
 			num_bytes -= ticket->bytes;
-			update_bytes_may_use(fs_info, space_info,
-					     ticket->bytes);
+			btrfs_space_info_update_bytes_may_use(fs_info,
+							      space_info,
+							      ticket->bytes);
 			ticket->bytes = 0;
 			space_info->tickets_id++;
 			wake_up(&ticket->wait);
@@ -5323,7 +5306,9 @@ void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
 			trace_btrfs_space_reservation(fs_info, "space_info",
 						      space_info->flags,
 						      num_bytes, 1);
-			update_bytes_may_use(fs_info, space_info, num_bytes);
+			btrfs_space_info_update_bytes_may_use(fs_info,
+							      space_info,
+							      num_bytes);
 			ticket->bytes -= num_bytes;
 			num_bytes = 0;
 		}
@@ -5616,14 +5601,16 @@ static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
 			num_bytes = min(num_bytes,
 					block_rsv->size - block_rsv->reserved);
 			block_rsv->reserved += num_bytes;
-			update_bytes_may_use(fs_info, sinfo, num_bytes);
+			btrfs_space_info_update_bytes_may_use(fs_info, sinfo,
+							      num_bytes);
 			trace_btrfs_space_reservation(fs_info, "space_info",
 						      sinfo->flags, num_bytes,
 						      1);
 		}
 	} else if (block_rsv->reserved > block_rsv->size) {
 		num_bytes = block_rsv->reserved - block_rsv->size;
-		update_bytes_may_use(fs_info, sinfo, -num_bytes);
+		btrfs_space_info_update_bytes_may_use(fs_info, sinfo,
+						      -num_bytes);
 		trace_btrfs_space_reservation(fs_info, "space_info",
 				      sinfo->flags, num_bytes, 0);
 		block_rsv->reserved = block_rsv->size;
@@ -6086,7 +6073,9 @@ static int update_block_group(struct btrfs_trans_handle *trans,
 			old_val -= num_bytes;
 			btrfs_set_block_group_used(&cache->item, old_val);
 			cache->pinned += num_bytes;
-			update_bytes_pinned(info, cache->space_info, num_bytes);
+			btrfs_space_info_update_bytes_pinned(info,
+							     cache->space_info,
+							     num_bytes);
 			cache->space_info->bytes_used -= num_bytes;
 			cache->space_info->disk_used -= num_bytes * factor;
 			spin_unlock(&cache->lock);
@@ -6161,7 +6150,8 @@ static int pin_down_extent(struct btrfs_block_group_cache *cache,
 	spin_lock(&cache->space_info->lock);
 	spin_lock(&cache->lock);
 	cache->pinned += num_bytes;
-	update_bytes_pinned(fs_info, cache->space_info, num_bytes);
+	btrfs_space_info_update_bytes_pinned(fs_info, cache->space_info,
+					     num_bytes);
 	if (reserved) {
 		cache->reserved -= num_bytes;
 		cache->space_info->bytes_reserved -= num_bytes;
@@ -6370,7 +6360,8 @@ static int btrfs_add_reserved_bytes(struct btrfs_block_group_cache *cache,
 	} else {
 		cache->reserved += num_bytes;
 		space_info->bytes_reserved += num_bytes;
-		update_bytes_may_use(cache->fs_info, space_info, -ram_bytes);
+		btrfs_space_info_update_bytes_may_use(cache->fs_info,
+						      space_info, -ram_bytes);
 		if (delalloc)
 			cache->delalloc_bytes += num_bytes;
 	}
@@ -6526,7 +6517,8 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info,
 		spin_lock(&space_info->lock);
 		spin_lock(&cache->lock);
 		cache->pinned -= len;
-		update_bytes_pinned(fs_info, space_info, -len);
+		btrfs_space_info_update_bytes_pinned(fs_info, space_info,
+						     -len);
 
 		trace_btrfs_space_reservation(fs_info, "pinned",
 					      space_info->flags, len, 0);
@@ -6547,8 +6539,9 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info,
 				to_add = min(len, global_rsv->size -
 					     global_rsv->reserved);
 				global_rsv->reserved += to_add;
-				update_bytes_may_use(fs_info, space_info,
-						     to_add);
+				btrfs_space_info_update_bytes_may_use(fs_info,
+								      space_info,
+								      to_add);
 				if (global_rsv->reserved >= global_rsv->size)
 					global_rsv->full = 1;
 				trace_btrfs_space_reservation(fs_info,
@@ -10808,7 +10801,8 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
 		spin_lock(&space_info->lock);
 		spin_lock(&block_group->lock);
 
-		update_bytes_pinned(fs_info, space_info, -block_group->pinned);
+		btrfs_space_info_update_bytes_pinned(fs_info, space_info,
+						     -block_group->pinned);
 		space_info->bytes_readonly += block_group->pinned;
 		percpu_counter_add_batch(&space_info->total_bytes_pinned,
 				   -block_group->pinned,
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
index c1f48f548cb6..800a02e54ac0 100644
--- a/fs/btrfs/space-info.h
+++ b/fs/btrfs/space-info.h
@@ -77,6 +77,28 @@ static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
 	return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
 		(space_info->flags & BTRFS_BLOCK_GROUP_DATA));
 }
+/*
+ *
+ * Declare a helper function to detect underflow of various space info members
+ */
+#define DECLARE_SPACE_INFO_UPDATE(name)					\
+static inline void							\
+btrfs_space_info_update_##name(struct btrfs_fs_info *fs_info,		\
+			       struct btrfs_space_info *sinfo,		\
+			       s64 bytes)				\
+{									\
+	lockdep_assert_held(&sinfo->lock);				\
+	trace_update_##name(fs_info, sinfo, sinfo->name, bytes);	\
+	if (bytes < 0 && sinfo->name < -bytes) {			\
+		WARN_ON(1);						\
+		sinfo->name = 0;					\
+		return;							\
+	}								\
+	sinfo->name += bytes;						\
+}
+
+DECLARE_SPACE_INFO_UPDATE(bytes_may_use);
+DECLARE_SPACE_INFO_UPDATE(bytes_pinned);
 
 void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
 				    struct btrfs_space_info *space_info,
-- 
2.14.3

[PATCH 07/11] btrfs: move btrfs_space_info_add_*_bytes to space-info.c

[Josef Bacik]

Now that we've moved all the pre-requisite stuff, move these two
functions.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/extent-tree.c | 114 -------------------------------------------------
 fs/btrfs/space-info.c  | 106 +++++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/space-info.h  |   8 ++++
 3 files changed, 114 insertions(+), 114 deletions(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 4ed194f4f60f..86f5b26c0bf1 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4487,14 +4487,6 @@ static void shrink_delalloc(struct btrfs_fs_info *fs_info, u64 to_reclaim,
 	}
 }
 
-struct reserve_ticket {
-	u64 orig_bytes;
-	u64 bytes;
-	int error;
-	struct list_head list;
-	wait_queue_head_t wait;
-};
-
 /**
  * maybe_commit_transaction - possibly commit the transaction if its ok to
  * @root - the root we're allocating for
@@ -5214,112 +5206,6 @@ int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
 	return 0;
 }
 
-/*
- * This is for space we already have accounted in space_info->bytes_may_use, so
- * basically when we're returning space from block_rsv's.
- */
-void btrfs_space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
-				    struct btrfs_space_info *space_info,
-				    u64 num_bytes)
-{
-	struct reserve_ticket *ticket;
-	struct list_head *head;
-	u64 used;
-	enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_NO_FLUSH;
-	bool check_overcommit = false;
-
-	spin_lock(&space_info->lock);
-	head = &space_info->priority_tickets;
-
-	/*
-	 * If we are over our limit then we need to check and see if we can
-	 * overcommit, and if we can't then we just need to free up our space
-	 * and not satisfy any requests.
-	 */
-	used = btrfs_space_info_used(space_info, true);
-	if (used - num_bytes >= space_info->total_bytes)
-		check_overcommit = true;
-again:
-	while (!list_empty(head) && num_bytes) {
-		ticket = list_first_entry(head, struct reserve_ticket,
-					  list);
-		/*
-		 * We use 0 bytes because this space is already reserved, so
-		 * adding the ticket space would be a double count.
-		 */
-		if (check_overcommit &&
-		    !btrfs_can_overcommit(fs_info, space_info, 0, flush,
-					  false))
-			break;
-		if (num_bytes >= ticket->bytes) {
-			list_del_init(&ticket->list);
-			num_bytes -= ticket->bytes;
-			ticket->bytes = 0;
-			space_info->tickets_id++;
-			wake_up(&ticket->wait);
-		} else {
-			ticket->bytes -= num_bytes;
-			num_bytes = 0;
-		}
-	}
-
-	if (num_bytes && head == &space_info->priority_tickets) {
-		head = &space_info->tickets;
-		flush = BTRFS_RESERVE_FLUSH_ALL;
-		goto again;
-	}
-	btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
-	trace_btrfs_space_reservation(fs_info, "space_info",
-				      space_info->flags, num_bytes, 0);
-	spin_unlock(&space_info->lock);
-}
-
-/*
- * This is for newly allocated space that isn't accounted in
- * space_info->bytes_may_use yet.  So if we allocate a chunk or unpin an extent
- * we use this helper.
- */
-void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
-				    struct btrfs_space_info *space_info,
-				    u64 num_bytes)
-{
-	struct reserve_ticket *ticket;
-	struct list_head *head = &space_info->priority_tickets;
-
-again:
-	while (!list_empty(head) && num_bytes) {
-		ticket = list_first_entry(head, struct reserve_ticket,
-					  list);
-		if (num_bytes >= ticket->bytes) {
-			trace_btrfs_space_reservation(fs_info, "space_info",
-						      space_info->flags,
-						      ticket->bytes, 1);
-			list_del_init(&ticket->list);
-			num_bytes -= ticket->bytes;
-			btrfs_space_info_update_bytes_may_use(fs_info,
-							      space_info,
-							      ticket->bytes);
-			ticket->bytes = 0;
-			space_info->tickets_id++;
-			wake_up(&ticket->wait);
-		} else {
-			trace_btrfs_space_reservation(fs_info, "space_info",
-						      space_info->flags,
-						      num_bytes, 1);
-			btrfs_space_info_update_bytes_may_use(fs_info,
-							      space_info,
-							      num_bytes);
-			ticket->bytes -= num_bytes;
-			num_bytes = 0;
-		}
-	}
-
-	if (num_bytes && head == &space_info->priority_tickets) {
-		head = &space_info->tickets;
-		goto again;
-	}
-}
-
 static u64 block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
 				    struct btrfs_block_rsv *block_rsv,
 				    struct btrfs_block_rsv *dest, u64 num_bytes,
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index 2cb9f3b6ffc9..579de5c0b5cb 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -243,3 +243,109 @@ int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
 		return 1;
 	return 0;
 }
+
+/*
+ * This is for space we already have accounted in space_info->bytes_may_use, so
+ * basically when we're returning space from block_rsv's.
+ */
+void btrfs_space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_space_info *space_info,
+				    u64 num_bytes)
+{
+	struct reserve_ticket *ticket;
+	struct list_head *head;
+	u64 used;
+	enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_NO_FLUSH;
+	bool check_overcommit = false;
+
+	spin_lock(&space_info->lock);
+	head = &space_info->priority_tickets;
+
+	/*
+	 * If we are over our limit then we need to check and see if we can
+	 * overcommit, and if we can't then we just need to free up our space
+	 * and not satisfy any requests.
+	 */
+	used = btrfs_space_info_used(space_info, true);
+	if (used - num_bytes >= space_info->total_bytes)
+		check_overcommit = true;
+again:
+	while (!list_empty(head) && num_bytes) {
+		ticket = list_first_entry(head, struct reserve_ticket,
+					  list);
+		/*
+		 * We use 0 bytes because this space is already reserved, so
+		 * adding the ticket space would be a double count.
+		 */
+		if (check_overcommit &&
+		    !btrfs_can_overcommit(fs_info, space_info, 0, flush,
+					  false))
+			break;
+		if (num_bytes >= ticket->bytes) {
+			list_del_init(&ticket->list);
+			num_bytes -= ticket->bytes;
+			ticket->bytes = 0;
+			space_info->tickets_id++;
+			wake_up(&ticket->wait);
+		} else {
+			ticket->bytes -= num_bytes;
+			num_bytes = 0;
+		}
+	}
+
+	if (num_bytes && head == &space_info->priority_tickets) {
+		head = &space_info->tickets;
+		flush = BTRFS_RESERVE_FLUSH_ALL;
+		goto again;
+	}
+	btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
+	trace_btrfs_space_reservation(fs_info, "space_info",
+				      space_info->flags, num_bytes, 0);
+	spin_unlock(&space_info->lock);
+}
+
+/*
+ * This is for newly allocated space that isn't accounted in
+ * space_info->bytes_may_use yet.  So if we allocate a chunk or unpin an extent
+ * we use this helper.
+ */
+void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_space_info *space_info,
+				    u64 num_bytes)
+{
+	struct reserve_ticket *ticket;
+	struct list_head *head = &space_info->priority_tickets;
+
+again:
+	while (!list_empty(head) && num_bytes) {
+		ticket = list_first_entry(head, struct reserve_ticket,
+					  list);
+		if (num_bytes >= ticket->bytes) {
+			trace_btrfs_space_reservation(fs_info, "space_info",
+						      space_info->flags,
+						      ticket->bytes, 1);
+			list_del_init(&ticket->list);
+			num_bytes -= ticket->bytes;
+			btrfs_space_info_update_bytes_may_use(fs_info,
+							      space_info,
+							      ticket->bytes);
+			ticket->bytes = 0;
+			space_info->tickets_id++;
+			wake_up(&ticket->wait);
+		} else {
+			trace_btrfs_space_reservation(fs_info, "space_info",
+						      space_info->flags,
+						      num_bytes, 1);
+			btrfs_space_info_update_bytes_may_use(fs_info,
+							      space_info,
+							      num_bytes);
+			ticket->bytes -= num_bytes;
+			num_bytes = 0;
+		}
+	}
+
+	if (num_bytes && head == &space_info->priority_tickets) {
+		head = &space_info->tickets;
+		goto again;
+	}
+}
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
index 800a02e54ac0..e566a2e79d69 100644
--- a/fs/btrfs/space-info.h
+++ b/fs/btrfs/space-info.h
@@ -72,6 +72,14 @@ struct btrfs_space_info {
 	struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
 };
 
+struct reserve_ticket {
+	u64 orig_bytes;
+	u64 bytes;
+	int error;
+	struct list_head list;
+	wait_queue_head_t wait;
+};
+
 static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
 {
 	return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
-- 
2.14.3

[PATCH 08/11] btrfs: export block_rsv_use_bytes

[Josef Bacik]

We are going to need this to move the metadata reservation stuff to
space_info.c.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/ctree.h       |  2 ++
 fs/btrfs/extent-tree.c | 14 ++++++--------
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index cceb1b5fab33..2aeb323cc86e 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2828,6 +2828,8 @@ int btrfs_block_rsv_refill(struct btrfs_root *root,
 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
 			    struct btrfs_block_rsv *dst_rsv, u64 num_bytes,
 			    bool update_size);
+int btrfs_block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
+			      u64 num_bytes);
 int btrfs_cond_migrate_bytes(struct btrfs_fs_info *fs_info,
 			     struct btrfs_block_rsv *dest, u64 num_bytes,
 			     int min_factor);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 86f5b26c0bf1..d21ee7af1e3e 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -53,8 +53,6 @@ static int find_next_key(struct btrfs_path *path, int level,
 static void dump_space_info(struct btrfs_fs_info *fs_info,
 			    struct btrfs_space_info *info, u64 bytes,
 			    int dump_block_groups);
-static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
-			       u64 num_bytes);
 
 static noinline int
 block_group_cache_done(struct btrfs_block_group_cache *cache)
@@ -5033,7 +5031,7 @@ static int reserve_metadata_bytes(struct btrfs_root *root,
 	if (ret == -ENOSPC &&
 	    unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) {
 		if (block_rsv != global_rsv &&
-		    !block_rsv_use_bytes(global_rsv, orig_bytes))
+		    !btrfs_block_rsv_use_bytes(global_rsv, orig_bytes))
 			ret = 0;
 	}
 	if (ret == -ENOSPC) {
@@ -5069,8 +5067,8 @@ static struct btrfs_block_rsv *get_block_rsv(
 	return block_rsv;
 }
 
-static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
-			       u64 num_bytes)
+int btrfs_block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
+			      u64 num_bytes)
 {
 	int ret = -ENOSPC;
 	spin_lock(&block_rsv->lock);
@@ -5268,7 +5266,7 @@ int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src,
 {
 	int ret;
 
-	ret = block_rsv_use_bytes(src, num_bytes);
+	ret = btrfs_block_rsv_use_bytes(src, num_bytes);
 	if (ret)
 		return ret;
 
@@ -8142,7 +8140,7 @@ use_block_rsv(struct btrfs_trans_handle *trans,
 	if (unlikely(block_rsv->size == 0))
 		goto try_reserve;
 again:
-	ret = block_rsv_use_bytes(block_rsv, blocksize);
+	ret = btrfs_block_rsv_use_bytes(block_rsv, blocksize);
 	if (!ret)
 		return block_rsv;
 
@@ -8180,7 +8178,7 @@ use_block_rsv(struct btrfs_trans_handle *trans,
 	 */
 	if (block_rsv->type != BTRFS_BLOCK_RSV_GLOBAL &&
 	    block_rsv->space_info == global_rsv->space_info) {
-		ret = block_rsv_use_bytes(global_rsv, blocksize);
+		ret = btrfs_block_rsv_use_bytes(global_rsv, blocksize);
 		if (!ret)
 			return global_rsv;
 	}
-- 
2.14.3

[PATCH 09/11] btrfs: move dump_space_info to space-info.c

[Josef Bacik]

We'll need this exported so we can use it in all the various was we need
to use it.  This is prep work to move reserve_metadata_bytes.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/extent-tree.c | 70 +++++---------------------------------------------
 fs/btrfs/space-info.c  | 55 +++++++++++++++++++++++++++++++++++++++
 fs/btrfs/space-info.h  |  3 +++
 3 files changed, 65 insertions(+), 63 deletions(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index d21ee7af1e3e..4e1e664d36b3 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -50,9 +50,6 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
 				     struct btrfs_delayed_extent_op *extent_op);
 static int find_next_key(struct btrfs_path *path, int level,
 			 struct btrfs_key *key);
-static void dump_space_info(struct btrfs_fs_info *fs_info,
-			    struct btrfs_space_info *info, u64 bytes,
-			    int dump_block_groups);
 
 static noinline int
 block_group_cache_done(struct btrfs_block_group_cache *cache)
@@ -4196,7 +4193,7 @@ void check_system_chunk(struct btrfs_trans_handle *trans, u64 type)
 	if (left < thresh && btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
 		btrfs_info(fs_info, "left=%llu, need=%llu, flags=%llu",
 			   left, thresh, type);
-		dump_space_info(fs_info, info, 0, 0);
+		btrfs_dump_space_info(fs_info, info, 0, 0);
 	}
 
 	if (left < thresh) {
@@ -5040,8 +5037,8 @@ static int reserve_metadata_bytes(struct btrfs_root *root,
 					      orig_bytes, 1);
 
 		if (btrfs_test_opt(fs_info, ENOSPC_DEBUG))
-			dump_space_info(fs_info, block_rsv->space_info,
-					orig_bytes, 0);
+			btrfs_dump_space_info(fs_info, block_rsv->space_info,
+					      orig_bytes, 0);
 	}
 	return ret;
 }
@@ -7653,60 +7650,6 @@ static noinline int find_free_extent(struct btrfs_fs_info *fs_info,
 	return ret;
 }
 
-#define DUMP_BLOCK_RSV(fs_info, rsv_name)				\
-do {									\
-	struct btrfs_block_rsv *__rsv = &(fs_info)->rsv_name;		\
-	spin_lock(&__rsv->lock);					\
-	btrfs_info(fs_info, #rsv_name ": size %llu reserved %llu",	\
-		   __rsv->size, __rsv->reserved);			\
-	spin_unlock(&__rsv->lock);					\
-} while (0)
-
-static void dump_space_info(struct btrfs_fs_info *fs_info,
-			    struct btrfs_space_info *info, u64 bytes,
-			    int dump_block_groups)
-{
-	struct btrfs_block_group_cache *cache;
-	int index = 0;
-
-	spin_lock(&info->lock);
-	btrfs_info(fs_info, "space_info %llu has %llu free, is %sfull",
-		   info->flags,
-		   info->total_bytes - btrfs_space_info_used(info, true),
-		   info->full ? "" : "not ");
-	btrfs_info(fs_info,
-		"space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu",
-		info->total_bytes, info->bytes_used, info->bytes_pinned,
-		info->bytes_reserved, info->bytes_may_use,
-		info->bytes_readonly);
-	spin_unlock(&info->lock);
-
-	DUMP_BLOCK_RSV(fs_info, global_block_rsv);
-	DUMP_BLOCK_RSV(fs_info, trans_block_rsv);
-	DUMP_BLOCK_RSV(fs_info, chunk_block_rsv);
-	DUMP_BLOCK_RSV(fs_info, delayed_block_rsv);
-	DUMP_BLOCK_RSV(fs_info, delayed_refs_rsv);
-
-	if (!dump_block_groups)
-		return;
-
-	down_read(&info->groups_sem);
-again:
-	list_for_each_entry(cache, &info->block_groups[index], list) {
-		spin_lock(&cache->lock);
-		btrfs_info(fs_info,
-			"block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s",
-			cache->key.objectid, cache->key.offset,
-			btrfs_block_group_used(&cache->item), cache->pinned,
-			cache->reserved, cache->ro ? "[readonly]" : "");
-		btrfs_dump_free_space(cache, bytes);
-		spin_unlock(&cache->lock);
-	}
-	if (++index < BTRFS_NR_RAID_TYPES)
-		goto again;
-	up_read(&info->groups_sem);
-}
-
 /*
  * btrfs_reserve_extent - entry point to the extent allocator. Tries to find a
  *			  hole that is at least as big as @num_bytes.
@@ -7787,7 +7730,8 @@ int btrfs_reserve_extent(struct btrfs_root *root, u64 ram_bytes,
 				  "allocation failed flags %llu, wanted %llu",
 				  flags, num_bytes);
 			if (sinfo)
-				dump_space_info(fs_info, sinfo, num_bytes, 1);
+				btrfs_dump_space_info(fs_info, sinfo,
+						      num_bytes, 1);
 		}
 	}
 
@@ -9305,7 +9249,7 @@ static int inc_block_group_ro(struct btrfs_block_group_cache *cache, int force)
 		btrfs_info(cache->fs_info,
 			"sinfo_used=%llu bg_num_bytes=%llu min_allocable=%llu",
 			sinfo_used, num_bytes, min_allocable_bytes);
-		dump_space_info(cache->fs_info, cache->space_info, 0, 0);
+		btrfs_dump_space_info(cache->fs_info, cache->space_info, 0, 0);
 	}
 	return ret;
 }
@@ -9787,7 +9731,7 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
 		if (WARN_ON(space_info->bytes_pinned > 0 ||
 			    space_info->bytes_reserved > 0 ||
 			    space_info->bytes_may_use > 0))
-			dump_space_info(info, space_info, 0, 0);
+			btrfs_dump_space_info(info, space_info, 0, 0);
 		list_del(&space_info->list);
 		for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
 			struct kobject *kobj;
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index 579de5c0b5cb..4fe5f229ce68 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -7,6 +7,7 @@
 #include "space-info.h"
 #include "sysfs.h"
 #include "volumes.h"
+#include "free-space-cache.h"
 
 u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
 			  bool may_use_included)
@@ -349,3 +350,57 @@ void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
 		goto again;
 	}
 }
+
+#define DUMP_BLOCK_RSV(fs_info, rsv_name)				\
+do {									\
+	struct btrfs_block_rsv *__rsv = &(fs_info)->rsv_name;		\
+	spin_lock(&__rsv->lock);					\
+	btrfs_info(fs_info, #rsv_name ": size %llu reserved %llu",	\
+		   __rsv->size, __rsv->reserved);			\
+	spin_unlock(&__rsv->lock);					\
+} while (0)
+
+void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
+			   struct btrfs_space_info *info, u64 bytes,
+			   int dump_block_groups)
+{
+	struct btrfs_block_group_cache *cache;
+	int index = 0;
+
+	spin_lock(&info->lock);
+	btrfs_info(fs_info, "space_info %llu has %llu free, is %sfull",
+		   info->flags,
+		   info->total_bytes - btrfs_space_info_used(info, true),
+		   info->full ? "" : "not ");
+	btrfs_info(fs_info,
+		"space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu",
+		info->total_bytes, info->bytes_used, info->bytes_pinned,
+		info->bytes_reserved, info->bytes_may_use,
+		info->bytes_readonly);
+	spin_unlock(&info->lock);
+
+	DUMP_BLOCK_RSV(fs_info, global_block_rsv);
+	DUMP_BLOCK_RSV(fs_info, trans_block_rsv);
+	DUMP_BLOCK_RSV(fs_info, chunk_block_rsv);
+	DUMP_BLOCK_RSV(fs_info, delayed_block_rsv);
+	DUMP_BLOCK_RSV(fs_info, delayed_refs_rsv);
+
+	if (!dump_block_groups)
+		return;
+
+	down_read(&info->groups_sem);
+again:
+	list_for_each_entry(cache, &info->block_groups[index], list) {
+		spin_lock(&cache->lock);
+		btrfs_info(fs_info,
+			"block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s",
+			cache->key.objectid, cache->key.offset,
+			btrfs_block_group_used(&cache->item), cache->pinned,
+			cache->reserved, cache->ro ? "[readonly]" : "");
+		btrfs_dump_free_space(cache, bytes);
+		spin_unlock(&cache->lock);
+	}
+	if (++index < BTRFS_NR_RAID_TYPES)
+		goto again;
+	up_read(&info->groups_sem);
+}
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
index e566a2e79d69..e2ab16e17fe1 100644
--- a/fs/btrfs/space-info.h
+++ b/fs/btrfs/space-info.h
@@ -128,5 +128,8 @@ int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
 			 struct btrfs_space_info *space_info, u64 bytes,
 			 enum btrfs_reserve_flush_enum flush,
 			 bool system_chunk);
+void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
+			   struct btrfs_space_info *info, u64 bytes,
+			   int dump_block_groups);
 
 #endif /* BTRFS_SPACE_INFO_H */
-- 
2.14.3

[PATCH 10/11] btrfs: move reserve_metadata_bytes and supporting code to space-info.c

[Josef Bacik]

This moves all of the metadata reservation code into space-info.c.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/extent-tree.c | 710 +------------------------------------------------
 fs/btrfs/space-info.c  | 698 ++++++++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/space-info.h  |   4 +
 3 files changed, 710 insertions(+), 702 deletions(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 4e1e664d36b3..3fc140dfcc58 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4348,701 +4348,6 @@ int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
 	return ret;
 }
 
-static void btrfs_writeback_inodes_sb_nr(struct btrfs_fs_info *fs_info,
-					 unsigned long nr_pages, int nr_items)
-{
-	struct super_block *sb = fs_info->sb;
-
-	if (down_read_trylock(&sb->s_umount)) {
-		writeback_inodes_sb_nr(sb, nr_pages, WB_REASON_FS_FREE_SPACE);
-		up_read(&sb->s_umount);
-	} else {
-		/*
-		 * We needn't worry the filesystem going from r/w to r/o though
-		 * we don't acquire ->s_umount mutex, because the filesystem
-		 * should guarantee the delalloc inodes list be empty after
-		 * the filesystem is readonly(all dirty pages are written to
-		 * the disk).
-		 */
-		btrfs_start_delalloc_roots(fs_info, nr_items);
-		if (!current->journal_info)
-			btrfs_wait_ordered_roots(fs_info, nr_items, 0, (u64)-1);
-	}
-}
-
-static inline u64 calc_reclaim_items_nr(struct btrfs_fs_info *fs_info,
-					u64 to_reclaim)
-{
-	u64 bytes;
-	u64 nr;
-
-	bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
-	nr = div64_u64(to_reclaim, bytes);
-	if (!nr)
-		nr = 1;
-	return nr;
-}
-
-#define EXTENT_SIZE_PER_ITEM	SZ_256K
-
-/*
- * shrink metadata reservation for delalloc
- */
-static void shrink_delalloc(struct btrfs_fs_info *fs_info, u64 to_reclaim,
-			    u64 orig, bool wait_ordered)
-{
-	struct btrfs_space_info *space_info;
-	struct btrfs_trans_handle *trans;
-	u64 delalloc_bytes;
-	u64 dio_bytes;
-	u64 async_pages;
-	u64 items;
-	long time_left;
-	unsigned long nr_pages;
-	int loops;
-
-	/* Calc the number of the pages we need flush for space reservation */
-	items = calc_reclaim_items_nr(fs_info, to_reclaim);
-	to_reclaim = items * EXTENT_SIZE_PER_ITEM;
-
-	trans = (struct btrfs_trans_handle *)current->journal_info;
-	space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
-
-	delalloc_bytes = percpu_counter_sum_positive(
-						&fs_info->delalloc_bytes);
-	dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
-	if (delalloc_bytes == 0 && dio_bytes == 0) {
-		if (trans)
-			return;
-		if (wait_ordered)
-			btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
-		return;
-	}
-
-	/*
-	 * If we are doing more ordered than delalloc we need to just wait on
-	 * ordered extents, otherwise we'll waste time trying to flush delalloc
-	 * that likely won't give us the space back we need.
-	 */
-	if (dio_bytes > delalloc_bytes)
-		wait_ordered = true;
-
-	loops = 0;
-	while ((delalloc_bytes || dio_bytes) && loops < 3) {
-		nr_pages = min(delalloc_bytes, to_reclaim) >> PAGE_SHIFT;
-
-		/*
-		 * Triggers inode writeback for up to nr_pages. This will invoke
-		 * ->writepages callback and trigger delalloc filling
-		 *  (btrfs_run_delalloc_range()).
-		 */
-		btrfs_writeback_inodes_sb_nr(fs_info, nr_pages, items);
-
-		/*
-		 * We need to wait for the compressed pages to start before
-		 * we continue.
-		 */
-		async_pages = atomic_read(&fs_info->async_delalloc_pages);
-		if (!async_pages)
-			goto skip_async;
-
-		/*
-		 * Calculate how many compressed pages we want to be written
-		 * before we continue. I.e if there are more async pages than we
-		 * require wait_event will wait until nr_pages are written.
-		 */
-		if (async_pages <= nr_pages)
-			async_pages = 0;
-		else
-			async_pages -= nr_pages;
-
-		wait_event(fs_info->async_submit_wait,
-			   atomic_read(&fs_info->async_delalloc_pages) <=
-			   (int)async_pages);
-skip_async:
-		spin_lock(&space_info->lock);
-		if (list_empty(&space_info->tickets) &&
-		    list_empty(&space_info->priority_tickets)) {
-			spin_unlock(&space_info->lock);
-			break;
-		}
-		spin_unlock(&space_info->lock);
-
-		loops++;
-		if (wait_ordered && !trans) {
-			btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
-		} else {
-			time_left = schedule_timeout_killable(1);
-			if (time_left)
-				break;
-		}
-		delalloc_bytes = percpu_counter_sum_positive(
-						&fs_info->delalloc_bytes);
-		dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
-	}
-}
-
-/**
- * maybe_commit_transaction - possibly commit the transaction if its ok to
- * @root - the root we're allocating for
- * @bytes - the number of bytes we want to reserve
- * @force - force the commit
- *
- * This will check to make sure that committing the transaction will actually
- * get us somewhere and then commit the transaction if it does.  Otherwise it
- * will return -ENOSPC.
- */
-static int may_commit_transaction(struct btrfs_fs_info *fs_info,
-				  struct btrfs_space_info *space_info)
-{
-	struct reserve_ticket *ticket = NULL;
-	struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_block_rsv;
-	struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
-	struct btrfs_trans_handle *trans;
-	u64 bytes_needed;
-	u64 reclaim_bytes = 0;
-
-	trans = (struct btrfs_trans_handle *)current->journal_info;
-	if (trans)
-		return -EAGAIN;
-
-	spin_lock(&space_info->lock);
-	if (!list_empty(&space_info->priority_tickets))
-		ticket = list_first_entry(&space_info->priority_tickets,
-					  struct reserve_ticket, list);
-	else if (!list_empty(&space_info->tickets))
-		ticket = list_first_entry(&space_info->tickets,
-					  struct reserve_ticket, list);
-	bytes_needed = (ticket) ? ticket->bytes : 0;
-	spin_unlock(&space_info->lock);
-
-	if (!bytes_needed)
-		return 0;
-
-	trans = btrfs_join_transaction(fs_info->extent_root);
-	if (IS_ERR(trans))
-		return PTR_ERR(trans);
-
-	/*
-	 * See if there is enough pinned space to make this reservation, or if
-	 * we have block groups that are going to be freed, allowing us to
-	 * possibly do a chunk allocation the next loop through.
-	 */
-	if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags) ||
-	    __percpu_counter_compare(&space_info->total_bytes_pinned,
-				     bytes_needed,
-				     BTRFS_TOTAL_BYTES_PINNED_BATCH) >= 0)
-		goto commit;
-
-	/*
-	 * See if there is some space in the delayed insertion reservation for
-	 * this reservation.
-	 */
-	if (space_info != delayed_rsv->space_info)
-		goto enospc;
-
-	spin_lock(&delayed_rsv->lock);
-	reclaim_bytes += delayed_rsv->reserved;
-	spin_unlock(&delayed_rsv->lock);
-
-	spin_lock(&delayed_refs_rsv->lock);
-	reclaim_bytes += delayed_refs_rsv->reserved;
-	spin_unlock(&delayed_refs_rsv->lock);
-	if (reclaim_bytes >= bytes_needed)
-		goto commit;
-	bytes_needed -= reclaim_bytes;
-
-	if (__percpu_counter_compare(&space_info->total_bytes_pinned,
-				   bytes_needed,
-				   BTRFS_TOTAL_BYTES_PINNED_BATCH) < 0)
-		goto enospc;
-
-commit:
-	return btrfs_commit_transaction(trans);
-enospc:
-	btrfs_end_transaction(trans);
-	return -ENOSPC;
-}
-
-/*
- * Try to flush some data based on policy set by @state. This is only advisory
- * and may fail for various reasons. The caller is supposed to examine the
- * state of @space_info to detect the outcome.
- */
-static void flush_space(struct btrfs_fs_info *fs_info,
-		       struct btrfs_space_info *space_info, u64 num_bytes,
-		       int state)
-{
-	struct btrfs_root *root = fs_info->extent_root;
-	struct btrfs_trans_handle *trans;
-	int nr;
-	int ret = 0;
-
-	switch (state) {
-	case FLUSH_DELAYED_ITEMS_NR:
-	case FLUSH_DELAYED_ITEMS:
-		if (state == FLUSH_DELAYED_ITEMS_NR)
-			nr = calc_reclaim_items_nr(fs_info, num_bytes) * 2;
-		else
-			nr = -1;
-
-		trans = btrfs_join_transaction(root);
-		if (IS_ERR(trans)) {
-			ret = PTR_ERR(trans);
-			break;
-		}
-		ret = btrfs_run_delayed_items_nr(trans, nr);
-		btrfs_end_transaction(trans);
-		break;
-	case FLUSH_DELALLOC:
-	case FLUSH_DELALLOC_WAIT:
-		shrink_delalloc(fs_info, num_bytes * 2, num_bytes,
-				state == FLUSH_DELALLOC_WAIT);
-		break;
-	case FLUSH_DELAYED_REFS_NR:
-	case FLUSH_DELAYED_REFS:
-		trans = btrfs_join_transaction(root);
-		if (IS_ERR(trans)) {
-			ret = PTR_ERR(trans);
-			break;
-		}
-		if (state == FLUSH_DELAYED_REFS_NR)
-			nr = calc_reclaim_items_nr(fs_info, num_bytes);
-		else
-			nr = 0;
-		btrfs_run_delayed_refs(trans, nr);
-		btrfs_end_transaction(trans);
-		break;
-	case ALLOC_CHUNK:
-	case ALLOC_CHUNK_FORCE:
-		trans = btrfs_join_transaction(root);
-		if (IS_ERR(trans)) {
-			ret = PTR_ERR(trans);
-			break;
-		}
-		ret = btrfs_chunk_alloc(trans,
-				btrfs_metadata_alloc_profile(fs_info),
-				(state == ALLOC_CHUNK) ? CHUNK_ALLOC_NO_FORCE :
-					CHUNK_ALLOC_FORCE);
-		btrfs_end_transaction(trans);
-		if (ret > 0 || ret == -ENOSPC)
-			ret = 0;
-		break;
-	case COMMIT_TRANS:
-		/*
-		 * If we have pending delayed iputs then we could free up a
-		 * bunch of pinned space, so make sure we run the iputs before
-		 * we do our pinned bytes check below.
-		 */
-		btrfs_run_delayed_iputs(fs_info);
-		btrfs_wait_on_delayed_iputs(fs_info);
-
-		ret = may_commit_transaction(fs_info, space_info);
-		break;
-	default:
-		ret = -ENOSPC;
-		break;
-	}
-
-	trace_btrfs_flush_space(fs_info, space_info->flags, num_bytes, state,
-				ret);
-	return;
-}
-
-static inline u64
-btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info,
-				 struct btrfs_space_info *space_info,
-				 bool system_chunk)
-{
-	struct reserve_ticket *ticket;
-	u64 used;
-	u64 expected;
-	u64 to_reclaim = 0;
-
-	list_for_each_entry(ticket, &space_info->tickets, list)
-		to_reclaim += ticket->bytes;
-	list_for_each_entry(ticket, &space_info->priority_tickets, list)
-		to_reclaim += ticket->bytes;
-	if (to_reclaim)
-		return to_reclaim;
-
-	to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M);
-	if (btrfs_can_overcommit(fs_info, space_info, to_reclaim,
-				 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
-		return 0;
-
-	used = btrfs_space_info_used(space_info, true);
-
-	if (btrfs_can_overcommit(fs_info, space_info, SZ_1M,
-				 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
-		expected = div_factor_fine(space_info->total_bytes, 95);
-	else
-		expected = div_factor_fine(space_info->total_bytes, 90);
-
-	if (used > expected)
-		to_reclaim = used - expected;
-	else
-		to_reclaim = 0;
-	to_reclaim = min(to_reclaim, space_info->bytes_may_use +
-				     space_info->bytes_reserved);
-	return to_reclaim;
-}
-
-static inline int need_do_async_reclaim(struct btrfs_fs_info *fs_info,
-					struct btrfs_space_info *space_info,
-					u64 used, bool system_chunk)
-{
-	u64 thresh = div_factor_fine(space_info->total_bytes, 98);
-
-	/* If we're just plain full then async reclaim just slows us down. */
-	if ((space_info->bytes_used + space_info->bytes_reserved) >= thresh)
-		return 0;
-
-	if (!btrfs_calc_reclaim_metadata_size(fs_info, space_info,
-					      system_chunk))
-		return 0;
-
-	return (used >= thresh && !btrfs_fs_closing(fs_info) &&
-		!test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state));
-}
-
-static bool wake_all_tickets(struct list_head *head)
-{
-	struct reserve_ticket *ticket;
-
-	while (!list_empty(head)) {
-		ticket = list_first_entry(head, struct reserve_ticket, list);
-		list_del_init(&ticket->list);
-		ticket->error = -ENOSPC;
-		wake_up(&ticket->wait);
-		if (ticket->bytes != ticket->orig_bytes)
-			return true;
-	}
-	return false;
-}
-
-/*
- * This is for normal flushers, we can wait all goddamned day if we want to.  We
- * will loop and continuously try to flush as long as we are making progress.
- * We count progress as clearing off tickets each time we have to loop.
- */
-static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
-{
-	struct btrfs_fs_info *fs_info;
-	struct btrfs_space_info *space_info;
-	u64 to_reclaim;
-	int flush_state;
-	int commit_cycles = 0;
-	u64 last_tickets_id;
-
-	fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work);
-	space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
-
-	spin_lock(&space_info->lock);
-	to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
-						      false);
-	if (!to_reclaim) {
-		space_info->flush = 0;
-		spin_unlock(&space_info->lock);
-		return;
-	}
-	last_tickets_id = space_info->tickets_id;
-	spin_unlock(&space_info->lock);
-
-	flush_state = FLUSH_DELAYED_ITEMS_NR;
-	do {
-		flush_space(fs_info, space_info, to_reclaim, flush_state);
-		spin_lock(&space_info->lock);
-		if (list_empty(&space_info->tickets)) {
-			space_info->flush = 0;
-			spin_unlock(&space_info->lock);
-			return;
-		}
-		to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info,
-							      space_info,
-							      false);
-		if (last_tickets_id == space_info->tickets_id) {
-			flush_state++;
-		} else {
-			last_tickets_id = space_info->tickets_id;
-			flush_state = FLUSH_DELAYED_ITEMS_NR;
-			if (commit_cycles)
-				commit_cycles--;
-		}
-
-		/*
-		 * We don't want to force a chunk allocation until we've tried
-		 * pretty hard to reclaim space.  Think of the case where we
-		 * freed up a bunch of space and so have a lot of pinned space
-		 * to reclaim.  We would rather use that than possibly create a
-		 * underutilized metadata chunk.  So if this is our first run
-		 * through the flushing state machine skip ALLOC_CHUNK_FORCE and
-		 * commit the transaction.  If nothing has changed the next go
-		 * around then we can force a chunk allocation.
-		 */
-		if (flush_state == ALLOC_CHUNK_FORCE && !commit_cycles)
-			flush_state++;
-
-		if (flush_state > COMMIT_TRANS) {
-			commit_cycles++;
-			if (commit_cycles > 2) {
-				if (wake_all_tickets(&space_info->tickets)) {
-					flush_state = FLUSH_DELAYED_ITEMS_NR;
-					commit_cycles--;
-				} else {
-					space_info->flush = 0;
-				}
-			} else {
-				flush_state = FLUSH_DELAYED_ITEMS_NR;
-			}
-		}
-		spin_unlock(&space_info->lock);
-	} while (flush_state <= COMMIT_TRANS);
-}
-
-void btrfs_init_async_reclaim_work(struct work_struct *work)
-{
-	INIT_WORK(work, btrfs_async_reclaim_metadata_space);
-}
-
-static const enum btrfs_flush_state priority_flush_states[] = {
-	FLUSH_DELAYED_ITEMS_NR,
-	FLUSH_DELAYED_ITEMS,
-	ALLOC_CHUNK,
-};
-
-static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info,
-					    struct btrfs_space_info *space_info,
-					    struct reserve_ticket *ticket)
-{
-	u64 to_reclaim;
-	int flush_state;
-
-	spin_lock(&space_info->lock);
-	to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
-						      false);
-	if (!to_reclaim) {
-		spin_unlock(&space_info->lock);
-		return;
-	}
-	spin_unlock(&space_info->lock);
-
-	flush_state = 0;
-	do {
-		flush_space(fs_info, space_info, to_reclaim,
-			    priority_flush_states[flush_state]);
-		flush_state++;
-		spin_lock(&space_info->lock);
-		if (ticket->bytes == 0) {
-			spin_unlock(&space_info->lock);
-			return;
-		}
-		spin_unlock(&space_info->lock);
-	} while (flush_state < ARRAY_SIZE(priority_flush_states));
-}
-
-static int wait_reserve_ticket(struct btrfs_fs_info *fs_info,
-			       struct btrfs_space_info *space_info,
-			       struct reserve_ticket *ticket)
-
-{
-	DEFINE_WAIT(wait);
-	u64 reclaim_bytes = 0;
-	int ret = 0;
-
-	spin_lock(&space_info->lock);
-	while (ticket->bytes > 0 && ticket->error == 0) {
-		ret = prepare_to_wait_event(&ticket->wait, &wait, TASK_KILLABLE);
-		if (ret) {
-			ret = -EINTR;
-			break;
-		}
-		spin_unlock(&space_info->lock);
-
-		schedule();
-
-		finish_wait(&ticket->wait, &wait);
-		spin_lock(&space_info->lock);
-	}
-	if (!ret)
-		ret = ticket->error;
-	if (!list_empty(&ticket->list))
-		list_del_init(&ticket->list);
-	if (ticket->bytes && ticket->bytes < ticket->orig_bytes)
-		reclaim_bytes = ticket->orig_bytes - ticket->bytes;
-	spin_unlock(&space_info->lock);
-
-	if (reclaim_bytes)
-		btrfs_space_info_add_old_bytes(fs_info, space_info,
-					       reclaim_bytes);
-	return ret;
-}
-
-/**
- * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
- * @root - the root we're allocating for
- * @space_info - the space info we want to allocate from
- * @orig_bytes - the number of bytes we want
- * @flush - whether or not we can flush to make our reservation
- *
- * This will reserve orig_bytes number of bytes from the space info associated
- * with the block_rsv.  If there is not enough space it will make an attempt to
- * flush out space to make room.  It will do this by flushing delalloc if
- * possible or committing the transaction.  If flush is 0 then no attempts to
- * regain reservations will be made and this will fail if there is not enough
- * space already.
- */
-static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
-				    struct btrfs_space_info *space_info,
-				    u64 orig_bytes,
-				    enum btrfs_reserve_flush_enum flush,
-				    bool system_chunk)
-{
-	struct reserve_ticket ticket;
-	u64 used;
-	u64 reclaim_bytes = 0;
-	int ret = 0;
-
-	ASSERT(orig_bytes);
-	ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_ALL);
-
-	spin_lock(&space_info->lock);
-	ret = -ENOSPC;
-	used = btrfs_space_info_used(space_info, true);
-
-	/*
-	 * If we have enough space then hooray, make our reservation and carry
-	 * on.  If not see if we can overcommit, and if we can, hooray carry on.
-	 * If not things get more complicated.
-	 */
-	if (used + orig_bytes <= space_info->total_bytes) {
-		btrfs_space_info_update_bytes_may_use(fs_info, space_info,
-						      orig_bytes);
-		trace_btrfs_space_reservation(fs_info, "space_info",
-					      space_info->flags, orig_bytes, 1);
-		ret = 0;
-	} else if (btrfs_can_overcommit(fs_info, space_info, orig_bytes, flush,
-					system_chunk)) {
-		btrfs_space_info_update_bytes_may_use(fs_info, space_info,
-						      orig_bytes);
-		trace_btrfs_space_reservation(fs_info, "space_info",
-					      space_info->flags, orig_bytes, 1);
-		ret = 0;
-	}
-
-	/*
-	 * If we couldn't make a reservation then setup our reservation ticket
-	 * and kick the async worker if it's not already running.
-	 *
-	 * If we are a priority flusher then we just need to add our ticket to
-	 * the list and we will do our own flushing further down.
-	 */
-	if (ret && flush != BTRFS_RESERVE_NO_FLUSH) {
-		ticket.orig_bytes = orig_bytes;
-		ticket.bytes = orig_bytes;
-		ticket.error = 0;
-		init_waitqueue_head(&ticket.wait);
-		if (flush == BTRFS_RESERVE_FLUSH_ALL) {
-			list_add_tail(&ticket.list, &space_info->tickets);
-			if (!space_info->flush) {
-				space_info->flush = 1;
-				trace_btrfs_trigger_flush(fs_info,
-							  space_info->flags,
-							  orig_bytes, flush,
-							  "enospc");
-				queue_work(system_unbound_wq,
-					   &fs_info->async_reclaim_work);
-			}
-		} else {
-			list_add_tail(&ticket.list,
-				      &space_info->priority_tickets);
-		}
-	} else if (!ret && space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
-		used += orig_bytes;
-		/*
-		 * We will do the space reservation dance during log replay,
-		 * which means we won't have fs_info->fs_root set, so don't do
-		 * the async reclaim as we will panic.
-		 */
-		if (!test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags) &&
-		    need_do_async_reclaim(fs_info, space_info,
-					  used, system_chunk) &&
-		    !work_busy(&fs_info->async_reclaim_work)) {
-			trace_btrfs_trigger_flush(fs_info, space_info->flags,
-						  orig_bytes, flush, "preempt");
-			queue_work(system_unbound_wq,
-				   &fs_info->async_reclaim_work);
-		}
-	}
-	spin_unlock(&space_info->lock);
-	if (!ret || flush == BTRFS_RESERVE_NO_FLUSH)
-		return ret;
-
-	if (flush == BTRFS_RESERVE_FLUSH_ALL)
-		return wait_reserve_ticket(fs_info, space_info, &ticket);
-
-	ret = 0;
-	priority_reclaim_metadata_space(fs_info, space_info, &ticket);
-	spin_lock(&space_info->lock);
-	if (ticket.bytes) {
-		if (ticket.bytes < orig_bytes)
-			reclaim_bytes = orig_bytes - ticket.bytes;
-		list_del_init(&ticket.list);
-		ret = -ENOSPC;
-	}
-	spin_unlock(&space_info->lock);
-
-	if (reclaim_bytes)
-		btrfs_space_info_add_old_bytes(fs_info, space_info,
-					       reclaim_bytes);
-	ASSERT(list_empty(&ticket.list));
-	return ret;
-}
-
-/**
- * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
- * @root - the root we're allocating for
- * @block_rsv - the block_rsv we're allocating for
- * @orig_bytes - the number of bytes we want
- * @flush - whether or not we can flush to make our reservation
- *
- * This will reserve orig_bytes number of bytes from the space info associated
- * with the block_rsv.  If there is not enough space it will make an attempt to
- * flush out space to make room.  It will do this by flushing delalloc if
- * possible or committing the transaction.  If flush is 0 then no attempts to
- * regain reservations will be made and this will fail if there is not enough
- * space already.
- */
-static int reserve_metadata_bytes(struct btrfs_root *root,
-				  struct btrfs_block_rsv *block_rsv,
-				  u64 orig_bytes,
-				  enum btrfs_reserve_flush_enum flush)
-{
-	struct btrfs_fs_info *fs_info = root->fs_info;
-	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
-	int ret;
-	bool system_chunk = (root == fs_info->chunk_root);
-
-	ret = __reserve_metadata_bytes(fs_info, block_rsv->space_info,
-				       orig_bytes, flush, system_chunk);
-	if (ret == -ENOSPC &&
-	    unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) {
-		if (block_rsv != global_rsv &&
-		    !btrfs_block_rsv_use_bytes(global_rsv, orig_bytes))
-			ret = 0;
-	}
-	if (ret == -ENOSPC) {
-		trace_btrfs_space_reservation(fs_info, "space_info:enospc",
-					      block_rsv->space_info->flags,
-					      orig_bytes, 1);
-
-		if (btrfs_test_opt(fs_info, ENOSPC_DEBUG))
-			btrfs_dump_space_info(fs_info, block_rsv->space_info,
-					      orig_bytes, 0);
-	}
-	return ret;
-}
-
 static struct btrfs_block_rsv *get_block_rsv(
 					const struct btrfs_trans_handle *trans,
 					const struct btrfs_root *root)
@@ -5191,8 +4496,8 @@ int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
 	if (!num_bytes)
 		return 0;
 
-	ret = reserve_metadata_bytes(fs_info->extent_root, block_rsv,
-				     num_bytes, flush);
+	ret = btrfs_reserve_metadata_bytes(fs_info->extent_root, block_rsv,
+					   num_bytes, flush);
 	if (ret)
 		return ret;
 	block_rsv_add_bytes(block_rsv, num_bytes, 0);
@@ -5318,7 +4623,7 @@ int btrfs_block_rsv_add(struct btrfs_root *root,
 	if (num_bytes == 0)
 		return 0;
 
-	ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
+	ret = btrfs_reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
 	if (!ret)
 		block_rsv_add_bytes(block_rsv, num_bytes, true);
 
@@ -5363,7 +4668,7 @@ int btrfs_block_rsv_refill(struct btrfs_root *root,
 	if (!ret)
 		return 0;
 
-	ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
+	ret = btrfs_reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
 	if (!ret) {
 		block_rsv_add_bytes(block_rsv, num_bytes, false);
 		return 0;
@@ -5737,7 +5042,8 @@ int btrfs_delalloc_reserve_metadata(struct btrfs_inode *inode, u64 num_bytes)
 	ret = btrfs_qgroup_reserve_meta_prealloc(root, qgroup_reserve, true);
 	if (ret)
 		goto out_fail;
-	ret = reserve_metadata_bytes(root, block_rsv, meta_reserve, flush);
+	ret = btrfs_reserve_metadata_bytes(root, block_rsv, meta_reserve,
+					   flush);
 	if (ret)
 		goto out_qgroup;
 
@@ -8111,8 +7417,8 @@ use_block_rsv(struct btrfs_trans_handle *trans,
 				"BTRFS: block rsv returned %d\n", ret);
 	}
 try_reserve:
-	ret = reserve_metadata_bytes(root, block_rsv, blocksize,
-				     BTRFS_RESERVE_NO_FLUSH);
+	ret = btrfs_reserve_metadata_bytes(root, block_rsv, blocksize,
+					   BTRFS_RESERVE_NO_FLUSH);
 	if (!ret)
 		return block_rsv;
 	/*
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index 4fe5f229ce68..3d6b197e6c0f 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -8,6 +8,9 @@
 #include "sysfs.h"
 #include "volumes.h"
 #include "free-space-cache.h"
+#include "ordered-data.h"
+#include "transaction.h"
+#include "math.h"
 
 u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
 			  bool may_use_included)
@@ -404,3 +407,698 @@ void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
 		goto again;
 	up_read(&info->groups_sem);
 }
+
+static void btrfs_writeback_inodes_sb_nr(struct btrfs_fs_info *fs_info,
+					 unsigned long nr_pages, int nr_items)
+{
+	struct super_block *sb = fs_info->sb;
+
+	if (down_read_trylock(&sb->s_umount)) {
+		writeback_inodes_sb_nr(sb, nr_pages, WB_REASON_FS_FREE_SPACE);
+		up_read(&sb->s_umount);
+	} else {
+		/*
+		 * We needn't worry the filesystem going from r/w to r/o though
+		 * we don't acquire ->s_umount mutex, because the filesystem
+		 * should guarantee the delalloc inodes list be empty after
+		 * the filesystem is readonly(all dirty pages are written to
+		 * the disk).
+		 */
+		btrfs_start_delalloc_roots(fs_info, nr_items);
+		if (!current->journal_info)
+			btrfs_wait_ordered_roots(fs_info, nr_items, 0, (u64)-1);
+	}
+}
+
+static inline u64 calc_reclaim_items_nr(struct btrfs_fs_info *fs_info,
+					u64 to_reclaim)
+{
+	u64 bytes;
+	u64 nr;
+
+	bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
+	nr = div64_u64(to_reclaim, bytes);
+	if (!nr)
+		nr = 1;
+	return nr;
+}
+
+#define EXTENT_SIZE_PER_ITEM	SZ_256K
+
+/*
+ * shrink metadata reservation for delalloc
+ */
+static void shrink_delalloc(struct btrfs_fs_info *fs_info, u64 to_reclaim,
+			    u64 orig, bool wait_ordered)
+{
+	struct btrfs_space_info *space_info;
+	struct btrfs_trans_handle *trans;
+	u64 delalloc_bytes;
+	u64 dio_bytes;
+	u64 async_pages;
+	u64 items;
+	long time_left;
+	unsigned long nr_pages;
+	int loops;
+
+	/* Calc the number of the pages we need flush for space reservation */
+	items = calc_reclaim_items_nr(fs_info, to_reclaim);
+	to_reclaim = items * EXTENT_SIZE_PER_ITEM;
+
+	trans = (struct btrfs_trans_handle *)current->journal_info;
+	space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
+
+	delalloc_bytes = percpu_counter_sum_positive(
+						&fs_info->delalloc_bytes);
+	dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
+	if (delalloc_bytes == 0 && dio_bytes == 0) {
+		if (trans)
+			return;
+		if (wait_ordered)
+			btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
+		return;
+	}
+
+	/*
+	 * If we are doing more ordered than delalloc we need to just wait on
+	 * ordered extents, otherwise we'll waste time trying to flush delalloc
+	 * that likely won't give us the space back we need.
+	 */
+	if (dio_bytes > delalloc_bytes)
+		wait_ordered = true;
+
+	loops = 0;
+	while ((delalloc_bytes || dio_bytes) && loops < 3) {
+		nr_pages = min(delalloc_bytes, to_reclaim) >> PAGE_SHIFT;
+
+		/*
+		 * Triggers inode writeback for up to nr_pages. This will invoke
+		 * ->writepages callback and trigger delalloc filling
+		 *  (btrfs_run_delalloc_range()).
+		 */
+		btrfs_writeback_inodes_sb_nr(fs_info, nr_pages, items);
+
+		/*
+		 * We need to wait for the compressed pages to start before
+		 * we continue.
+		 */
+		async_pages = atomic_read(&fs_info->async_delalloc_pages);
+		if (!async_pages)
+			goto skip_async;
+
+		/*
+		 * Calculate how many compressed pages we want to be written
+		 * before we continue. I.e if there are more async pages than we
+		 * require wait_event will wait until nr_pages are written.
+		 */
+		if (async_pages <= nr_pages)
+			async_pages = 0;
+		else
+			async_pages -= nr_pages;
+
+		wait_event(fs_info->async_submit_wait,
+			   atomic_read(&fs_info->async_delalloc_pages) <=
+			   (int)async_pages);
+skip_async:
+		spin_lock(&space_info->lock);
+		if (list_empty(&space_info->tickets) &&
+		    list_empty(&space_info->priority_tickets)) {
+			spin_unlock(&space_info->lock);
+			break;
+		}
+		spin_unlock(&space_info->lock);
+
+		loops++;
+		if (wait_ordered && !trans) {
+			btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
+		} else {
+			time_left = schedule_timeout_killable(1);
+			if (time_left)
+				break;
+		}
+		delalloc_bytes = percpu_counter_sum_positive(
+						&fs_info->delalloc_bytes);
+		dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
+	}
+}
+
+/**
+ * maybe_commit_transaction - possibly commit the transaction if its ok to
+ * @root - the root we're allocating for
+ * @bytes - the number of bytes we want to reserve
+ * @force - force the commit
+ *
+ * This will check to make sure that committing the transaction will actually
+ * get us somewhere and then commit the transaction if it does.  Otherwise it
+ * will return -ENOSPC.
+ */
+static int may_commit_transaction(struct btrfs_fs_info *fs_info,
+				  struct btrfs_space_info *space_info)
+{
+	struct reserve_ticket *ticket = NULL;
+	struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_block_rsv;
+	struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
+	struct btrfs_trans_handle *trans;
+	u64 bytes_needed;
+	u64 reclaim_bytes = 0;
+
+	trans = (struct btrfs_trans_handle *)current->journal_info;
+	if (trans)
+		return -EAGAIN;
+
+	spin_lock(&space_info->lock);
+	if (!list_empty(&space_info->priority_tickets))
+		ticket = list_first_entry(&space_info->priority_tickets,
+					  struct reserve_ticket, list);
+	else if (!list_empty(&space_info->tickets))
+		ticket = list_first_entry(&space_info->tickets,
+					  struct reserve_ticket, list);
+	bytes_needed = (ticket) ? ticket->bytes : 0;
+	spin_unlock(&space_info->lock);
+
+	if (!bytes_needed)
+		return 0;
+
+	trans = btrfs_join_transaction(fs_info->extent_root);
+	if (IS_ERR(trans))
+		return PTR_ERR(trans);
+
+	/*
+	 * See if there is enough pinned space to make this reservation, or if
+	 * we have block groups that are going to be freed, allowing us to
+	 * possibly do a chunk allocation the next loop through.
+	 */
+	if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags) ||
+	    __percpu_counter_compare(&space_info->total_bytes_pinned,
+				     bytes_needed,
+				     BTRFS_TOTAL_BYTES_PINNED_BATCH) >= 0)
+		goto commit;
+
+	/*
+	 * See if there is some space in the delayed insertion reservation for
+	 * this reservation.
+	 */
+	if (space_info != delayed_rsv->space_info)
+		goto enospc;
+
+	spin_lock(&delayed_rsv->lock);
+	reclaim_bytes += delayed_rsv->reserved;
+	spin_unlock(&delayed_rsv->lock);
+
+	spin_lock(&delayed_refs_rsv->lock);
+	reclaim_bytes += delayed_refs_rsv->reserved;
+	spin_unlock(&delayed_refs_rsv->lock);
+	if (reclaim_bytes >= bytes_needed)
+		goto commit;
+	bytes_needed -= reclaim_bytes;
+
+	if (__percpu_counter_compare(&space_info->total_bytes_pinned,
+				   bytes_needed,
+				   BTRFS_TOTAL_BYTES_PINNED_BATCH) < 0)
+		goto enospc;
+
+commit:
+	return btrfs_commit_transaction(trans);
+enospc:
+	btrfs_end_transaction(trans);
+	return -ENOSPC;
+}
+
+/*
+ * Try to flush some data based on policy set by @state. This is only advisory
+ * and may fail for various reasons. The caller is supposed to examine the
+ * state of @space_info to detect the outcome.
+ */
+static void flush_space(struct btrfs_fs_info *fs_info,
+		       struct btrfs_space_info *space_info, u64 num_bytes,
+		       int state)
+{
+	struct btrfs_root *root = fs_info->extent_root;
+	struct btrfs_trans_handle *trans;
+	int nr;
+	int ret = 0;
+
+	switch (state) {
+	case FLUSH_DELAYED_ITEMS_NR:
+	case FLUSH_DELAYED_ITEMS:
+		if (state == FLUSH_DELAYED_ITEMS_NR)
+			nr = calc_reclaim_items_nr(fs_info, num_bytes) * 2;
+		else
+			nr = -1;
+
+		trans = btrfs_join_transaction(root);
+		if (IS_ERR(trans)) {
+			ret = PTR_ERR(trans);
+			break;
+		}
+		ret = btrfs_run_delayed_items_nr(trans, nr);
+		btrfs_end_transaction(trans);
+		break;
+	case FLUSH_DELALLOC:
+	case FLUSH_DELALLOC_WAIT:
+		shrink_delalloc(fs_info, num_bytes * 2, num_bytes,
+				state == FLUSH_DELALLOC_WAIT);
+		break;
+	case FLUSH_DELAYED_REFS_NR:
+	case FLUSH_DELAYED_REFS:
+		trans = btrfs_join_transaction(root);
+		if (IS_ERR(trans)) {
+			ret = PTR_ERR(trans);
+			break;
+		}
+		if (state == FLUSH_DELAYED_REFS_NR)
+			nr = calc_reclaim_items_nr(fs_info, num_bytes);
+		else
+			nr = 0;
+		btrfs_run_delayed_refs(trans, nr);
+		btrfs_end_transaction(trans);
+		break;
+	case ALLOC_CHUNK:
+	case ALLOC_CHUNK_FORCE:
+		trans = btrfs_join_transaction(root);
+		if (IS_ERR(trans)) {
+			ret = PTR_ERR(trans);
+			break;
+		}
+		ret = btrfs_chunk_alloc(trans,
+				btrfs_metadata_alloc_profile(fs_info),
+				(state == ALLOC_CHUNK) ? CHUNK_ALLOC_NO_FORCE :
+					CHUNK_ALLOC_FORCE);
+		btrfs_end_transaction(trans);
+		if (ret > 0 || ret == -ENOSPC)
+			ret = 0;
+		break;
+	case COMMIT_TRANS:
+		/*
+		 * If we have pending delayed iputs then we could free up a
+		 * bunch of pinned space, so make sure we run the iputs before
+		 * we do our pinned bytes check below.
+		 */
+		btrfs_run_delayed_iputs(fs_info);
+		btrfs_wait_on_delayed_iputs(fs_info);
+
+		ret = may_commit_transaction(fs_info, space_info);
+		break;
+	default:
+		ret = -ENOSPC;
+		break;
+	}
+
+	trace_btrfs_flush_space(fs_info, space_info->flags, num_bytes, state,
+				ret);
+	return;
+}
+
+static inline u64
+btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info,
+				 struct btrfs_space_info *space_info,
+				 bool system_chunk)
+{
+	struct reserve_ticket *ticket;
+	u64 used;
+	u64 expected;
+	u64 to_reclaim = 0;
+
+	list_for_each_entry(ticket, &space_info->tickets, list)
+		to_reclaim += ticket->bytes;
+	list_for_each_entry(ticket, &space_info->priority_tickets, list)
+		to_reclaim += ticket->bytes;
+	if (to_reclaim)
+		return to_reclaim;
+
+	to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M);
+	if (btrfs_can_overcommit(fs_info, space_info, to_reclaim,
+				 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
+		return 0;
+
+	used = btrfs_space_info_used(space_info, true);
+
+	if (btrfs_can_overcommit(fs_info, space_info, SZ_1M,
+				 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
+		expected = div_factor_fine(space_info->total_bytes, 95);
+	else
+		expected = div_factor_fine(space_info->total_bytes, 90);
+
+	if (used > expected)
+		to_reclaim = used - expected;
+	else
+		to_reclaim = 0;
+	to_reclaim = min(to_reclaim, space_info->bytes_may_use +
+				     space_info->bytes_reserved);
+	return to_reclaim;
+}
+
+static inline int need_do_async_reclaim(struct btrfs_fs_info *fs_info,
+					struct btrfs_space_info *space_info,
+					u64 used, bool system_chunk)
+{
+	u64 thresh = div_factor_fine(space_info->total_bytes, 98);
+
+	/* If we're just plain full then async reclaim just slows us down. */
+	if ((space_info->bytes_used + space_info->bytes_reserved) >= thresh)
+		return 0;
+
+	if (!btrfs_calc_reclaim_metadata_size(fs_info, space_info,
+					      system_chunk))
+		return 0;
+
+	return (used >= thresh && !btrfs_fs_closing(fs_info) &&
+		!test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state));
+}
+
+static bool wake_all_tickets(struct list_head *head)
+{
+	struct reserve_ticket *ticket;
+
+	while (!list_empty(head)) {
+		ticket = list_first_entry(head, struct reserve_ticket, list);
+		list_del_init(&ticket->list);
+		ticket->error = -ENOSPC;
+		wake_up(&ticket->wait);
+		if (ticket->bytes != ticket->orig_bytes)
+			return true;
+	}
+	return false;
+}
+
+/*
+ * This is for normal flushers, we can wait all goddamned day if we want to.  We
+ * will loop and continuously try to flush as long as we are making progress.
+ * We count progress as clearing off tickets each time we have to loop.
+ */
+static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
+{
+	struct btrfs_fs_info *fs_info;
+	struct btrfs_space_info *space_info;
+	u64 to_reclaim;
+	int flush_state;
+	int commit_cycles = 0;
+	u64 last_tickets_id;
+
+	fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work);
+	space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
+
+	spin_lock(&space_info->lock);
+	to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
+						      false);
+	if (!to_reclaim) {
+		space_info->flush = 0;
+		spin_unlock(&space_info->lock);
+		return;
+	}
+	last_tickets_id = space_info->tickets_id;
+	spin_unlock(&space_info->lock);
+
+	flush_state = FLUSH_DELAYED_ITEMS_NR;
+	do {
+		flush_space(fs_info, space_info, to_reclaim, flush_state);
+		spin_lock(&space_info->lock);
+		if (list_empty(&space_info->tickets)) {
+			space_info->flush = 0;
+			spin_unlock(&space_info->lock);
+			return;
+		}
+		to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info,
+							      space_info,
+							      false);
+		if (last_tickets_id == space_info->tickets_id) {
+			flush_state++;
+		} else {
+			last_tickets_id = space_info->tickets_id;
+			flush_state = FLUSH_DELAYED_ITEMS_NR;
+			if (commit_cycles)
+				commit_cycles--;
+		}
+
+		/*
+		 * We don't want to force a chunk allocation until we've tried
+		 * pretty hard to reclaim space.  Think of the case where we
+		 * freed up a bunch of space and so have a lot of pinned space
+		 * to reclaim.  We would rather use that than possibly create a
+		 * underutilized metadata chunk.  So if this is our first run
+		 * through the flushing state machine skip ALLOC_CHUNK_FORCE and
+		 * commit the transaction.  If nothing has changed the next go
+		 * around then we can force a chunk allocation.
+		 */
+		if (flush_state == ALLOC_CHUNK_FORCE && !commit_cycles)
+			flush_state++;
+
+		if (flush_state > COMMIT_TRANS) {
+			commit_cycles++;
+			if (commit_cycles > 2) {
+				if (wake_all_tickets(&space_info->tickets)) {
+					flush_state = FLUSH_DELAYED_ITEMS_NR;
+					commit_cycles--;
+				} else {
+					space_info->flush = 0;
+				}
+			} else {
+				flush_state = FLUSH_DELAYED_ITEMS_NR;
+			}
+		}
+		spin_unlock(&space_info->lock);
+	} while (flush_state <= COMMIT_TRANS);
+}
+
+void btrfs_init_async_reclaim_work(struct work_struct *work)
+{
+	INIT_WORK(work, btrfs_async_reclaim_metadata_space);
+}
+
+static const enum btrfs_flush_state priority_flush_states[] = {
+	FLUSH_DELAYED_ITEMS_NR,
+	FLUSH_DELAYED_ITEMS,
+	ALLOC_CHUNK,
+};
+
+static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info,
+					    struct btrfs_space_info *space_info,
+					    struct reserve_ticket *ticket)
+{
+	u64 to_reclaim;
+	int flush_state;
+
+	spin_lock(&space_info->lock);
+	to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
+						      false);
+	if (!to_reclaim) {
+		spin_unlock(&space_info->lock);
+		return;
+	}
+	spin_unlock(&space_info->lock);
+
+	flush_state = 0;
+	do {
+		flush_space(fs_info, space_info, to_reclaim,
+			    priority_flush_states[flush_state]);
+		flush_state++;
+		spin_lock(&space_info->lock);
+		if (ticket->bytes == 0) {
+			spin_unlock(&space_info->lock);
+			return;
+		}
+		spin_unlock(&space_info->lock);
+	} while (flush_state < ARRAY_SIZE(priority_flush_states));
+}
+
+static int wait_reserve_ticket(struct btrfs_fs_info *fs_info,
+			       struct btrfs_space_info *space_info,
+			       struct reserve_ticket *ticket)
+
+{
+	DEFINE_WAIT(wait);
+	u64 reclaim_bytes = 0;
+	int ret = 0;
+
+	spin_lock(&space_info->lock);
+	while (ticket->bytes > 0 && ticket->error == 0) {
+		ret = prepare_to_wait_event(&ticket->wait, &wait, TASK_KILLABLE);
+		if (ret) {
+			ret = -EINTR;
+			break;
+		}
+		spin_unlock(&space_info->lock);
+
+		schedule();
+
+		finish_wait(&ticket->wait, &wait);
+		spin_lock(&space_info->lock);
+	}
+	if (!ret)
+		ret = ticket->error;
+	if (!list_empty(&ticket->list))
+		list_del_init(&ticket->list);
+	if (ticket->bytes && ticket->bytes < ticket->orig_bytes)
+		reclaim_bytes = ticket->orig_bytes - ticket->bytes;
+	spin_unlock(&space_info->lock);
+
+	if (reclaim_bytes)
+		btrfs_space_info_add_old_bytes(fs_info, space_info,
+					       reclaim_bytes);
+	return ret;
+}
+
+/**
+ * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
+ * @root - the root we're allocating for
+ * @space_info - the space info we want to allocate from
+ * @orig_bytes - the number of bytes we want
+ * @flush - whether or not we can flush to make our reservation
+ *
+ * This will reserve orig_bytes number of bytes from the space info associated
+ * with the block_rsv.  If there is not enough space it will make an attempt to
+ * flush out space to make room.  It will do this by flushing delalloc if
+ * possible or committing the transaction.  If flush is 0 then no attempts to
+ * regain reservations will be made and this will fail if there is not enough
+ * space already.
+ */
+static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_space_info *space_info,
+				    u64 orig_bytes,
+				    enum btrfs_reserve_flush_enum flush,
+				    bool system_chunk)
+{
+	struct reserve_ticket ticket;
+	u64 used;
+	u64 reclaim_bytes = 0;
+	int ret = 0;
+
+	ASSERT(orig_bytes);
+	ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_ALL);
+
+	spin_lock(&space_info->lock);
+	ret = -ENOSPC;
+	used = btrfs_space_info_used(space_info, true);
+
+	/*
+	 * If we have enough space then hooray, make our reservation and carry
+	 * on.  If not see if we can overcommit, and if we can, hooray carry on.
+	 * If not things get more complicated.
+	 */
+	if (used + orig_bytes <= space_info->total_bytes) {
+		btrfs_space_info_update_bytes_may_use(fs_info, space_info,
+						      orig_bytes);
+		trace_btrfs_space_reservation(fs_info, "space_info",
+					      space_info->flags, orig_bytes, 1);
+		ret = 0;
+	} else if (btrfs_can_overcommit(fs_info, space_info, orig_bytes, flush,
+					system_chunk)) {
+		btrfs_space_info_update_bytes_may_use(fs_info, space_info,
+						      orig_bytes);
+		trace_btrfs_space_reservation(fs_info, "space_info",
+					      space_info->flags, orig_bytes, 1);
+		ret = 0;
+	}
+
+	/*
+	 * If we couldn't make a reservation then setup our reservation ticket
+	 * and kick the async worker if it's not already running.
+	 *
+	 * If we are a priority flusher then we just need to add our ticket to
+	 * the list and we will do our own flushing further down.
+	 */
+	if (ret && flush != BTRFS_RESERVE_NO_FLUSH) {
+		ticket.orig_bytes = orig_bytes;
+		ticket.bytes = orig_bytes;
+		ticket.error = 0;
+		init_waitqueue_head(&ticket.wait);
+		if (flush == BTRFS_RESERVE_FLUSH_ALL) {
+			list_add_tail(&ticket.list, &space_info->tickets);
+			if (!space_info->flush) {
+				space_info->flush = 1;
+				trace_btrfs_trigger_flush(fs_info,
+							  space_info->flags,
+							  orig_bytes, flush,
+							  "enospc");
+				queue_work(system_unbound_wq,
+					   &fs_info->async_reclaim_work);
+			}
+		} else {
+			list_add_tail(&ticket.list,
+				      &space_info->priority_tickets);
+		}
+	} else if (!ret && space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
+		used += orig_bytes;
+		/*
+		 * We will do the space reservation dance during log replay,
+		 * which means we won't have fs_info->fs_root set, so don't do
+		 * the async reclaim as we will panic.
+		 */
+		if (!test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags) &&
+		    need_do_async_reclaim(fs_info, space_info,
+					  used, system_chunk) &&
+		    !work_busy(&fs_info->async_reclaim_work)) {
+			trace_btrfs_trigger_flush(fs_info, space_info->flags,
+						  orig_bytes, flush, "preempt");
+			queue_work(system_unbound_wq,
+				   &fs_info->async_reclaim_work);
+		}
+	}
+	spin_unlock(&space_info->lock);
+	if (!ret || flush == BTRFS_RESERVE_NO_FLUSH)
+		return ret;
+
+	if (flush == BTRFS_RESERVE_FLUSH_ALL)
+		return wait_reserve_ticket(fs_info, space_info, &ticket);
+
+	ret = 0;
+	priority_reclaim_metadata_space(fs_info, space_info, &ticket);
+	spin_lock(&space_info->lock);
+	if (ticket.bytes) {
+		if (ticket.bytes < orig_bytes)
+			reclaim_bytes = orig_bytes - ticket.bytes;
+		list_del_init(&ticket.list);
+		ret = -ENOSPC;
+	}
+	spin_unlock(&space_info->lock);
+
+	if (reclaim_bytes)
+		btrfs_space_info_add_old_bytes(fs_info, space_info,
+					       reclaim_bytes);
+	ASSERT(list_empty(&ticket.list));
+	return ret;
+}
+
+/**
+ * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
+ * @root - the root we're allocating for
+ * @block_rsv - the block_rsv we're allocating for
+ * @orig_bytes - the number of bytes we want
+ * @flush - whether or not we can flush to make our reservation
+ *
+ * This will reserve orig_bytes number of bytes from the space info associated
+ * with the block_rsv.  If there is not enough space it will make an attempt to
+ * flush out space to make room.  It will do this by flushing delalloc if
+ * possible or committing the transaction.  If flush is 0 then no attempts to
+ * regain reservations will be made and this will fail if there is not enough
+ * space already.
+ */
+int btrfs_reserve_metadata_bytes(struct btrfs_root *root,
+				 struct btrfs_block_rsv *block_rsv,
+				 u64 orig_bytes,
+				 enum btrfs_reserve_flush_enum flush)
+{
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+	int ret;
+	bool system_chunk = (root == fs_info->chunk_root);
+
+	ret = __reserve_metadata_bytes(fs_info, block_rsv->space_info,
+				       orig_bytes, flush, system_chunk);
+	if (ret == -ENOSPC &&
+	    unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) {
+		if (block_rsv != global_rsv &&
+		    !btrfs_block_rsv_use_bytes(global_rsv, orig_bytes))
+			ret = 0;
+	}
+	if (ret == -ENOSPC) {
+		trace_btrfs_space_reservation(fs_info, "space_info:enospc",
+					      block_rsv->space_info->flags,
+					      orig_bytes, 1);
+
+		if (btrfs_test_opt(fs_info, ENOSPC_DEBUG))
+			btrfs_dump_space_info(fs_info, block_rsv->space_info,
+					      orig_bytes, 0);
+	}
+	return ret;
+}
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
index e2ab16e17fe1..05bfd8e5b10e 100644
--- a/fs/btrfs/space-info.h
+++ b/fs/btrfs/space-info.h
@@ -131,5 +131,9 @@ int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
 void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
 			   struct btrfs_space_info *info, u64 bytes,
 			   int dump_block_groups);
+int btrfs_reserve_metadata_bytes(struct btrfs_root *root,
+				 struct btrfs_block_rsv *block_rsv,
+				 u64 orig_bytes,
+				 enum btrfs_reserve_flush_enum flush);
 
 #endif /* BTRFS_SPACE_INFO_H */
-- 
2.14.3

[PATCH 11/11] btrfs: unexport can_overcommit

[Josef Bacik]

Now that we've moved all of the users to space-info.c, unexport it and
name it back to can_overcommit.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/space-info.c | 23 +++++++++++------------
 fs/btrfs/space-info.h |  4 ----
 2 files changed, 11 insertions(+), 16 deletions(-)

diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index 3d6b197e6c0f..4efb817d1f0f 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -185,10 +185,10 @@ static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)
 	return (global->size << 1);
 }
 
-int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
-			 struct btrfs_space_info *space_info, u64 bytes,
-			 enum btrfs_reserve_flush_enum flush,
-			 bool system_chunk)
+static int can_overcommit(struct btrfs_fs_info *fs_info,
+			  struct btrfs_space_info *space_info, u64 bytes,
+			  enum btrfs_reserve_flush_enum flush,
+			  bool system_chunk)
 {
 	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
 	u64 profile;
@@ -282,8 +282,7 @@ void btrfs_space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
 		 * adding the ticket space would be a double count.
 		 */
 		if (check_overcommit &&
-		    !btrfs_can_overcommit(fs_info, space_info, 0, flush,
-					  false))
+		    !can_overcommit(fs_info, space_info, 0, flush, false))
 			break;
 		if (num_bytes >= ticket->bytes) {
 			list_del_init(&ticket->list);
@@ -727,14 +726,14 @@ btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info,
 		return to_reclaim;
 
 	to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M);
-	if (btrfs_can_overcommit(fs_info, space_info, to_reclaim,
-				 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
+	if (can_overcommit(fs_info, space_info, to_reclaim,
+			   BTRFS_RESERVE_FLUSH_ALL, system_chunk))
 		return 0;
 
 	used = btrfs_space_info_used(space_info, true);
 
-	if (btrfs_can_overcommit(fs_info, space_info, SZ_1M,
-				 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
+	if (can_overcommit(fs_info, space_info, SZ_1M,
+			   BTRFS_RESERVE_FLUSH_ALL, system_chunk))
 		expected = div_factor_fine(space_info->total_bytes, 95);
 	else
 		expected = div_factor_fine(space_info->total_bytes, 90);
@@ -981,8 +980,8 @@ static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
 		trace_btrfs_space_reservation(fs_info, "space_info",
 					      space_info->flags, orig_bytes, 1);
 		ret = 0;
-	} else if (btrfs_can_overcommit(fs_info, space_info, orig_bytes, flush,
-					system_chunk)) {
+	} else if (can_overcommit(fs_info, space_info, orig_bytes, flush,
+				  system_chunk)) {
 		btrfs_space_info_update_bytes_may_use(fs_info, space_info,
 						      orig_bytes);
 		trace_btrfs_space_reservation(fs_info, "space_info",
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
index 05bfd8e5b10e..af9c3b016d6a 100644
--- a/fs/btrfs/space-info.h
+++ b/fs/btrfs/space-info.h
@@ -124,10 +124,6 @@ struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
 u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
 			  bool may_use_included);
 void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
-int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
-			 struct btrfs_space_info *space_info, u64 bytes,
-			 enum btrfs_reserve_flush_enum flush,
-			 bool system_chunk);
 void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
 			   struct btrfs_space_info *info, u64 bytes,
 			   int dump_block_groups);
-- 
2.14.3

Re: [PATCH 00/11] btrfs: move the space_info code out of extent-tree.c

[Nikolay Borisov]

On 18.06.19 г. 23:09 ч., Josef Bacik wrote:
> This is the first pass at making extent-tree.c much smaller.  I've purposefully
> done no other cleanups or changes.  The places where I needed to modify callers
> were done in separate patches.  The only time I moved and changed callers in
> large chunks was the moving of reserve_metadata_bytes out of extent-tree.c, and
> that was just to rename the users of reserve_metadata_bytes to
> btrfs_reserve_metadata_bytes.
> 
> There is 0 functional change in this series.  The next step is to move the other
> space reservation code that is specific to delayed_refs, inodes, etc.  But I
> wanted to start with this to make sure we're all onboard with this approach
> before I do other things.
> 
> The diffstat for the whole series is the following

Looks good,

Reviewed-by: Nikolay Borisov <nborisov@suse.com>

> 
>  fs/btrfs/Makefile           |    2 +-
>  fs/btrfs/ctree.h            |   97 +---
>  fs/btrfs/extent-tree.c      | 1277 +++----------------------------------------
>  fs/btrfs/free-space-cache.c |    1 +
>  fs/btrfs/ioctl.c            |    1 +
>  fs/btrfs/space-info.c       | 1103 +++++++++++++++++++++++++++++++++++++
>  fs/btrfs/space-info.h       |  135 +++++
>  fs/btrfs/super.c            |    1 +
>  fs/btrfs/sysfs.c            |    1 +
>  fs/btrfs/volumes.c          |    1 +
>  10 files changed, 1343 insertions(+), 1276 deletions(-)
> 
> Thanks,
> 
> Josef
> 

Re: [PATCH 04/11] btrfs: move the space_info handling code to space-info.c

[David Sterba]

On Tue, Jun 18, 2019 at 04:09:19PM -0400, Josef Bacik wrote:
> --- /dev/null
> +++ b/fs/btrfs/space-info.c
> @@ -0,0 +1,177 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2019 Facebook.  All rights reserved.
> + */

How does the copyright claim work here? You're just moving code from a
file (extent-tree.c) that has

  "Copyright (C) 2007 Oracle.  All rights reserved."

Adding company copyright to new files that implement something
completely new seems to be fine and I don't object against adding it,
though personally I think it's pointless to add the copyrights when
there's the Signed-off-by mechanism and full and immutable history of
changes tracked in git and newly the SPDX tag to disperse any confusion
about licensing of individual files.

Re: [PATCH 04/11] btrfs: move the space_info handling code to space-info.c

[Josef Bacik]

On Tue, Jun 25, 2019 at 01:58:43PM +0200, David Sterba wrote:
> On Tue, Jun 18, 2019 at 04:09:19PM -0400, Josef Bacik wrote:
> > --- /dev/null
> > +++ b/fs/btrfs/space-info.c
> > @@ -0,0 +1,177 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright (C) 2019 Facebook.  All rights reserved.
> > + */
> 
> How does the copyright claim work here? You're just moving code from a
> file (extent-tree.c) that has
> 
>   "Copyright (C) 2007 Oracle.  All rights reserved."
> 
> Adding company copyright to new files that implement something
> completely new seems to be fine and I don't object against adding it,
> though personally I think it's pointless to add the copyrights when
> there's the Signed-off-by mechanism and full and immutable history of
> changes tracked in git and newly the SPDX tag to disperse any confusion
> about licensing of individual files.
> 

Yeah I agree, fix it however you like, the signed-off chain seems to be what's
important.  Thanks,

Josef

Re: [PATCH 04/11] btrfs: move the space_info handling code to space-info.c

[David Sterba]

On Tue, Jun 25, 2019 at 08:54:30AM -0400, Josef Bacik wrote:
> On Tue, Jun 25, 2019 at 01:58:43PM +0200, David Sterba wrote:
> > On Tue, Jun 18, 2019 at 04:09:19PM -0400, Josef Bacik wrote:
> > > --- /dev/null
> > > +++ b/fs/btrfs/space-info.c
> > > @@ -0,0 +1,177 @@
> > > +/* SPDX-License-Identifier: GPL-2.0 */
> > > +/*
> > > + * Copyright (C) 2019 Facebook.  All rights reserved.
> > > + */
> > 
> > How does the copyright claim work here? You're just moving code from a
> > file (extent-tree.c) that has
> > 
> >   "Copyright (C) 2007 Oracle.  All rights reserved."
> > 
> > Adding company copyright to new files that implement something
> > completely new seems to be fine and I don't object against adding it,
> > though personally I think it's pointless to add the copyrights when
> > there's the Signed-off-by mechanism and full and immutable history of
> > changes tracked in git and newly the SPDX tag to disperse any confusion
> > about licensing of individual files.
> > 
> 
> Yeah I agree, fix it however you like, the signed-off chain seems to be what's
> important.  Thanks,

Thanks, I've summarized that on wiki so we can point to that when
needed.

https://btrfs.wiki.kernel.org/index.php/Developer%27s_FAQ#Copyright_notices_in_files

Re: [PATCH 00/11] btrfs: move the space_info code out of extent-tree.c

[David Sterba]

On Tue, Jun 18, 2019 at 04:09:15PM -0400, Josef Bacik wrote:
> This is the first pass at making extent-tree.c much smaller.  I've purposefully
> done no other cleanups or changes.  The places where I needed to modify callers
> were done in separate patches.  The only time I moved and changed callers in
> large chunks was the moving of reserve_metadata_bytes out of extent-tree.c, and
> that was just to rename the users of reserve_metadata_bytes to
> btrfs_reserve_metadata_bytes.
> 
> There is 0 functional change in this series.  The next step is to move the other
> space reservation code that is specific to delayed_refs, inodes, etc.  But I
> wanted to start with this to make sure we're all onboard with this approach
> before I do other things.
> 
> The diffstat for the whole series is the following
> 
>  fs/btrfs/Makefile           |    2 +-
>  fs/btrfs/ctree.h            |   97 +---
>  fs/btrfs/extent-tree.c      | 1277 +++----------------------------------------
>  fs/btrfs/free-space-cache.c |    1 +
>  fs/btrfs/ioctl.c            |    1 +
>  fs/btrfs/space-info.c       | 1103 +++++++++++++++++++++++++++++++++++++
>  fs/btrfs/space-info.h       |  135 +++++
>  fs/btrfs/super.c            |    1 +
>  fs/btrfs/sysfs.c            |    1 +
>  fs/btrfs/volumes.c          |    1 +
>  10 files changed, 1343 insertions(+), 1276 deletions(-)

With the removed copyright notice, patches added to misc-next.