Merge tag 'for-5.5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

97d0bf96 · Linus Torvalds <[email protected]> · 2019-11-25 12:01:49 -08:00

Pull btrfs updates from David Sterba:
 "User visible changes:
   - new block group profiles: RAID1 with 3- and 4- copies
       - RAID1 in btrfs has always 2 copies, now add support for 3 and 4
       - this is an incompat feature (named RAID1C34)
       - recommended use of RAID1C3 is replacement of RAID6 profile on
         metadata, this brings a more reliable resiliency against 2
         device loss/damage

   - support for new checksums
       - per-filesystem, set at mkfs time
       - fast hash (crc32c successor): xxhash, 64bit digest
       - strong hashes (both 256bit): sha256 (slower, FIPS), blake2b
         (faster)
       - the blake2b module goes via the crypto tree, btrfs.ko has a
         soft dependency

   - speed up lseek, don't take inode locks unnecessarily, this can
     speed up parallel SEEK_CUR/SEEK_SET/SEEK_END by 80%

   - send:
       - allow clone operations within the same file
       - limit maximum number of sent clone references to avoid slow
         backref walking

   - error message improvements: device scan prints process name and PID

  Core changes:
   - cleanups
       - remove unique workqueue helpers, used to provide a way to avoid
         deadlocks in the workqueue code, now done in a simpler way
       - remove lots of indirect function calls in compression code
       - extent IO tree code moved out of extent_io.c
       - cleanup backup superblock handling at mount time
       - transaction life cycle documentation and cleanups
       - locking code cleanups, annotations and documentation
       - add more cold, const, pure function attributes
       - removal of unused or redundant struct members or variables

   - new tree-checker sanity tests
       - try to detect missing INODE_ITEM, cross-reference checks of
         DIR_ITEM, DIR_INDEX, INODE_REF, and XATTR_* items

   - remove own bio scheduling code (used to avoid checksum submissions
     being stuck behind other IO), replaced by cgroup controller-based
     code to allow better control and avoid priority inversions in cases
     where the custom and cgroup scheduling disagreed

  Fixes:
   - avoid getting stuck during cyclic writebacks

   - fix trimming of ranges crossing block group boundaries

   - fix rename exchange on subvolumes, all involved subvolumes need to
     be recorded in the transaction"

* tag 'for-5.5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (137 commits)
  btrfs: drop bdev argument from submit_extent_page
  btrfs: remove extent_map::bdev
  btrfs: drop bio_set_dev where not needed
  btrfs: get bdev directly from fs_devices in submit_extent_page
  btrfs: record all roots for rename exchange on a subvol
  Btrfs: fix block group remaining RO forever after error during device replace
  btrfs: scrub: Don't check free space before marking a block group RO
  btrfs: change btrfs_fs_devices::rotating to bool
  btrfs: change btrfs_fs_devices::seeding to bool
  btrfs: rename btrfs_block_group_cache
  btrfs: block-group: Reuse the item key from caller of read_one_block_group()
  btrfs: block-group: Refactor btrfs_read_block_groups()
  btrfs: document extent buffer locking
  btrfs: access eb::blocking_writers according to ACCESS_ONCE policies
  btrfs: set blocking_writers directly, no increment or decrement
  btrfs: merge blocking_writers branches in btrfs_tree_read_lock
  btrfs: drop incompat bit for raid1c34 after last block group is gone
  btrfs: add incompat for raid1 with 3, 4 copies
  btrfs: add support for 4-copy replication (raid1c4)
  btrfs: add support for 3-copy replication (raid1c3)
  ...

Commit: 97d0bf96a0d0986f466c3ff59f2ace801e33dc69
Parents: 1b88176b · fa17ed06

Merge commit. Changes below are compared with the first parent: 1b88176b.

Changes

66 files changed · +2780 −2619

File	Status	Add	Del	Content
fs/btrfs/Kconfig	modified	+2	−0	View file
fs/btrfs/async-thread.c	modified	+53	−60	View file
fs/btrfs/async-thread.h	modified	+4	−33	View file
fs/btrfs/block-group.c	modified	+302	−287	View file
fs/btrfs/block-group.h	modified	+26	−25	View file
fs/btrfs/btrfs_inode.h	modified	+0	−3	View file
fs/btrfs/compression.c	modified	+198	−71	View file
fs/btrfs/compression.h	modified	+7	−39	View file
fs/btrfs/ctree.c	modified	+125	−162	View file
fs/btrfs/ctree.h	modified	+26	−25	View file
fs/btrfs/delalloc-space.c	modified	+5	−16	View file
fs/btrfs/delayed-inode.c	modified	+13	−5	View file
fs/btrfs/dev-replace.c	modified	+1	−1	View file
fs/btrfs/dev-replace.h	modified	+1	−1	View file
fs/btrfs/disk-io.c	modified	+166	−199	View file
fs/btrfs/disk-io.h	modified	+2	−2	View file
fs/btrfs/export.c	modified	+2	−2	View file
fs/btrfs/extent-io-tree.h	added	+248	−0	View file
fs/btrfs/extent-tree.c	modified	+82	−64	View file
fs/btrfs/extent_io.c	modified	+59	−61	View file
fs/btrfs/extent_io.h	modified	+1	−230	View file
fs/btrfs/extent_map.c	modified	+5	−1	View file
fs/btrfs/extent_map.h	modified	+2	−9	View file
fs/btrfs/file-item.c	modified	+0	−1	View file
fs/btrfs/file.c	modified	+33	−41	View file
fs/btrfs/free-space-cache.c	modified	+61	−57	View file
fs/btrfs/free-space-cache.h	modified	+18	−21	View file
fs/btrfs/free-space-tree.c	modified	+66	−67	View file
fs/btrfs/free-space-tree.h	modified	+9	−9	View file
fs/btrfs/inode.c	modified	+98	−72	View file
fs/btrfs/ioctl.c	modified	+21	−28	View file
fs/btrfs/locking.c	modified	+255	−54	View file
fs/btrfs/locking.h	modified	+12	−1	View file
fs/btrfs/lzo.c	modified	+10	−43	View file
fs/btrfs/misc.h	modified	+11	−0	View file
fs/btrfs/ordered-data.c	modified	+1	−6	View file
fs/btrfs/ordered-data.h	modified	+1	−1	View file
fs/btrfs/print-tree.c	modified	+3	−3	View file
fs/btrfs/props.c	modified	+2	−4	View file
fs/btrfs/qgroup.c	modified	+4	−7	View file
fs/btrfs/qgroup.h	modified	+1	−1	View file
fs/btrfs/raid56.c	modified	+49	−52	View file
fs/btrfs/reada.c	modified	+8	−11	View file
fs/btrfs/relocation.c	modified	+20	−23	View file
fs/btrfs/scrub.c	modified	+38	−62	View file
fs/btrfs/send.c	modified	+38	−7	View file
fs/btrfs/space-info.c	modified	+3	−5	View file
fs/btrfs/space-info.h	modified	+1	−2	View file
fs/btrfs/super.c	modified	+19	−7	View file
fs/btrfs/sysfs.c	modified	+43	−4	View file
fs/btrfs/sysfs.h	modified	+1	−1	View file
fs/btrfs/tests/btrfs-tests.c	modified	+5	−6	View file
fs/btrfs/tests/btrfs-tests.h	modified	+2	−2	View file
fs/btrfs/tests/free-space-tests.c	modified	+7	−8	View file
fs/btrfs/tests/free-space-tree-tests.c	modified	+45	−56	View file
fs/btrfs/transaction.c	modified	+81	−17	View file
fs/btrfs/transaction.h	modified	+1	−4	View file
fs/btrfs/tree-checker.c	modified	+165	−46	View file
fs/btrfs/tree-log.c	modified	+58	−78	View file
fs/btrfs/volumes.c	modified	+137	−357	View file
fs/btrfs/volumes.h	modified	+8	−16	View file
fs/btrfs/zlib.c	modified	+12	−40	View file
fs/btrfs/zstd.c	modified	+17	−30	View file
include/trace/events/btrfs.h	modified	+64	−67	View file
include/uapi/linux/btrfs.h	modified	+4	−1	View file
include/uapi/linux/btrfs_tree.h	modified	+18	−5	View file

Only the first 600 diff lines are shown. Download the complete patch.

fs/btrfs/Kconfig

View file

diff --git a/fs/btrfs/Kconfig b/fs/btrfs/Kconfig
index 38651fa..75b6d10 100644
--- a/fs/btrfs/Kconfig
+++ b/fs/btrfs/Kconfig
@@ -5,6 +5,8 @@ config BTRFS_FS
 	select CRYPTO
 	select CRYPTO_CRC32C
 	select LIBCRC32C
+	select CRYPTO_XXHASH
+	select CRYPTO_SHA256
 	select ZLIB_INFLATE
 	select ZLIB_DEFLATE
 	select LZO_COMPRESS

fs/btrfs/async-thread.c

View file

diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c
index 2e9e13f..1d32a07 100644
--- a/fs/btrfs/async-thread.c
+++ b/fs/btrfs/async-thread.c
@@ -53,24 +53,12 @@ struct btrfs_workqueue {
 	struct __btrfs_workqueue *high;
 };
 
-static void normal_work_helper(struct btrfs_work *work);
-
-#define BTRFS_WORK_HELPER(name)					\
-noinline_for_stack void btrfs_##name(struct work_struct *arg)		\
-{									\
-	struct btrfs_work *work = container_of(arg, struct btrfs_work,	\
-					       normal_work);		\
-	normal_work_helper(work);					\
-}
-
-struct btrfs_fs_info *
-btrfs_workqueue_owner(const struct __btrfs_workqueue *wq)
+struct btrfs_fs_info * __pure btrfs_workqueue_owner(const struct __btrfs_workqueue *wq)
 {
 	return wq->fs_info;
 }
 
-struct btrfs_fs_info *
-btrfs_work_owner(const struct btrfs_work *work)
+struct btrfs_fs_info * __pure btrfs_work_owner(const struct btrfs_work *work)
 {
 	return work->wq->fs_info;
 }
@@ -89,29 +77,6 @@ bool btrfs_workqueue_normal_congested(const struct btrfs_workqueue *wq)
 	return atomic_read(&wq->normal->pending) > wq->normal->thresh * 2;
 }
 
-BTRFS_WORK_HELPER(worker_helper);
-BTRFS_WORK_HELPER(delalloc_helper);
-BTRFS_WORK_HELPER(flush_delalloc_helper);
-BTRFS_WORK_HELPER(cache_helper);
-BTRFS_WORK_HELPER(submit_helper);
-BTRFS_WORK_HELPER(fixup_helper);
-BTRFS_WORK_HELPER(endio_helper);
-BTRFS_WORK_HELPER(endio_meta_helper);
-BTRFS_WORK_HELPER(endio_meta_write_helper);
-BTRFS_WORK_HELPER(endio_raid56_helper);
-BTRFS_WORK_HELPER(endio_repair_helper);
-BTRFS_WORK_HELPER(rmw_helper);
-BTRFS_WORK_HELPER(endio_write_helper);
-BTRFS_WORK_HELPER(freespace_write_helper);
-BTRFS_WORK_HELPER(delayed_meta_helper);
-BTRFS_WORK_HELPER(readahead_helper);
-BTRFS_WORK_HELPER(qgroup_rescan_helper);
-BTRFS_WORK_HELPER(extent_refs_helper);
-BTRFS_WORK_HELPER(scrub_helper);
-BTRFS_WORK_HELPER(scrubwrc_helper);
-BTRFS_WORK_HELPER(scrubnc_helper);
-BTRFS_WORK_HELPER(scrubparity_helper);
-
 static struct __btrfs_workqueue *
 __btrfs_alloc_workqueue(struct btrfs_fs_info *fs_info, const char *name,
 			unsigned int flags, int limit_active, int thresh)
@@ -252,16 +217,16 @@ out:
 	}
 }
 
-static void run_ordered_work(struct __btrfs_workqueue *wq)
+static void run_ordered_work(struct __btrfs_workqueue *wq,
+			     struct btrfs_work *self)
 {
 	struct list_head *list = &wq->ordered_list;
 	struct btrfs_work *work;
 	spinlock_t *lock = &wq->list_lock;
 	unsigned long flags;
+	bool free_self = false;
 
 	while (1) {
-		void *wtag;
-
 		spin_lock_irqsave(lock, flags);
 		if (list_empty(list))
 			break;
@@ -287,22 +252,53 @@ static void run_ordered_work(struct __btrfs_workqueue *wq)
 		list_del(&work->ordered_list);
 		spin_unlock_irqrestore(lock, flags);
 
-		/*
-		 * We don't want to call the ordered free functions with the
-		 * lock held though. Save the work as tag for the trace event,
-		 * because the callback could free the structure.
-		 */
-		wtag = work;
-		work->ordered_free(work);
-		trace_btrfs_all_work_done(wq->fs_info, wtag);
+		if (work == self) {
+			/*
+			 * This is the work item that the worker is currently
+			 * executing.
+			 *
+			 * The kernel workqueue code guarantees non-reentrancy
+			 * of work items. I.e., if a work item with the same
+			 * address and work function is queued twice, the second
+			 * execution is blocked until the first one finishes. A
+			 * work item may be freed and recycled with the same
+			 * work function; the workqueue code assumes that the
+			 * original work item cannot depend on the recycled work
+			 * item in that case (see find_worker_executing_work()).
+			 *
+			 * Note that different types of Btrfs work can depend on
+			 * each other, and one type of work on one Btrfs
+			 * filesystem may even depend on the same type of work
+			 * on another Btrfs filesystem via, e.g., a loop device.
+			 * Therefore, we must not allow the current work item to
+			 * be recycled until we are really done, otherwise we
+			 * break the above assumption and can deadlock.
+			 */
+			free_self = true;
+		} else {
+			/*
+			 * We don't want to call the ordered free functions with
+			 * the lock held.
+			 */
+			work->ordered_free(work);
+			/* NB: work must not be dereferenced past this point. */
+			trace_btrfs_all_work_done(wq->fs_info, work);
+		}
 	}
 	spin_unlock_irqrestore(lock, flags);
+
+	if (free_self) {
+		self->ordered_free(self);
+		/* NB: self must not be dereferenced past this point. */
+		trace_btrfs_all_work_done(wq->fs_info, self);
+	}
 }
 
-static void normal_work_helper(struct btrfs_work *work)
+static void btrfs_work_helper(struct work_struct *normal_work)
 {
+	struct btrfs_work *work = container_of(normal_work, struct btrfs_work,
+					       normal_work);
 	struct __btrfs_workqueue *wq;
-	void *wtag;
 	int need_order = 0;
 
 	/*
@@ -316,29 +312,26 @@ static void normal_work_helper(struct btrfs_work *work)
 	if (work->ordered_func)
 		need_order = 1;
 	wq = work->wq;
-	/* Safe for tracepoints in case work gets freed by the callback */
-	wtag = work;
 
 	trace_btrfs_work_sched(work);
 	thresh_exec_hook(wq);
 	work->func(work);
 	if (need_order) {
 		set_bit(WORK_DONE_BIT, &work->flags);
-		run_ordered_work(wq);
+		run_ordered_work(wq, work);
+	} else {
+		/* NB: work must not be dereferenced past this point. */
+		trace_btrfs_all_work_done(wq->fs_info, work);
 	}
-	if (!need_order)
-		trace_btrfs_all_work_done(wq->fs_info, wtag);
 }
 
-void btrfs_init_work(struct btrfs_work *work, btrfs_work_func_t uniq_func,
-		     btrfs_func_t func,
-		     btrfs_func_t ordered_func,
-		     btrfs_func_t ordered_free)
+void btrfs_init_work(struct btrfs_work *work, btrfs_func_t func,
+		     btrfs_func_t ordered_func, btrfs_func_t ordered_free)
 {
 	work->func = func;
 	work->ordered_func = ordered_func;
 	work->ordered_free = ordered_free;
-	INIT_WORK(&work->normal_work, uniq_func);
+	INIT_WORK(&work->normal_work, btrfs_work_helper);
 	INIT_LIST_HEAD(&work->ordered_list);
 	work->flags = 0;
 }

fs/btrfs/async-thread.h

View file

diff --git a/fs/btrfs/async-thread.h b/fs/btrfs/async-thread.h
index 7861c9f..a443430 100644
--- a/fs/btrfs/async-thread.h
+++ b/fs/btrfs/async-thread.h
@@ -29,49 +29,20 @@ struct btrfs_work {
 	unsigned long flags;
 };
 
-#define BTRFS_WORK_HELPER_PROTO(name)					\
-void btrfs_##name(struct work_struct *arg)
-
-BTRFS_WORK_HELPER_PROTO(worker_helper);
-BTRFS_WORK_HELPER_PROTO(delalloc_helper);
-BTRFS_WORK_HELPER_PROTO(flush_delalloc_helper);
-BTRFS_WORK_HELPER_PROTO(cache_helper);
-BTRFS_WORK_HELPER_PROTO(submit_helper);
-BTRFS_WORK_HELPER_PROTO(fixup_helper);
-BTRFS_WORK_HELPER_PROTO(endio_helper);
-BTRFS_WORK_HELPER_PROTO(endio_meta_helper);
-BTRFS_WORK_HELPER_PROTO(endio_meta_write_helper);
-BTRFS_WORK_HELPER_PROTO(endio_raid56_helper);
-BTRFS_WORK_HELPER_PROTO(endio_repair_helper);
-BTRFS_WORK_HELPER_PROTO(rmw_helper);
-BTRFS_WORK_HELPER_PROTO(endio_write_helper);
-BTRFS_WORK_HELPER_PROTO(freespace_write_helper);
-BTRFS_WORK_HELPER_PROTO(delayed_meta_helper);
-BTRFS_WORK_HELPER_PROTO(readahead_helper);
-BTRFS_WORK_HELPER_PROTO(qgroup_rescan_helper);
-BTRFS_WORK_HELPER_PROTO(extent_refs_helper);
-BTRFS_WORK_HELPER_PROTO(scrub_helper);
-BTRFS_WORK_HELPER_PROTO(scrubwrc_helper);
-BTRFS_WORK_HELPER_PROTO(scrubnc_helper);
-BTRFS_WORK_HELPER_PROTO(scrubparity_helper);
-
-
 struct btrfs_workqueue *btrfs_alloc_workqueue(struct btrfs_fs_info *fs_info,
 					      const char *name,
 					      unsigned int flags,
 					      int limit_active,
 					      int thresh);
-void btrfs_init_work(struct btrfs_work *work, btrfs_work_func_t helper,
-		     btrfs_func_t func,
-		     btrfs_func_t ordered_func,
-		     btrfs_func_t ordered_free);
+void btrfs_init_work(struct btrfs_work *work, btrfs_func_t func,
+		     btrfs_func_t ordered_func, btrfs_func_t ordered_free);
 void btrfs_queue_work(struct btrfs_workqueue *wq,
 		      struct btrfs_work *work);
 void btrfs_destroy_workqueue(struct btrfs_workqueue *wq);
 void btrfs_workqueue_set_max(struct btrfs_workqueue *wq, int max);
 void btrfs_set_work_high_priority(struct btrfs_work *work);
-struct btrfs_fs_info *btrfs_work_owner(const struct btrfs_work *work);
-struct btrfs_fs_info *btrfs_workqueue_owner(const struct __btrfs_workqueue *wq);
+struct btrfs_fs_info * __pure btrfs_work_owner(const struct btrfs_work *work);
+struct btrfs_fs_info * __pure btrfs_workqueue_owner(const struct __btrfs_workqueue *wq);
 bool btrfs_workqueue_normal_congested(const struct btrfs_workqueue *wq);
 
 #endif

fs/btrfs/block-group.c

View file

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index 670700c..6934a5b 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -120,12 +120,12 @@ u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags)
 	return get_alloc_profile(fs_info, orig_flags);
 }
 
-void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
+void btrfs_get_block_group(struct btrfs_block_group *cache)
 {
 	atomic_inc(&cache->count);
 }
 
-void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
+void btrfs_put_block_group(struct btrfs_block_group *cache)
 {
 	if (atomic_dec_and_test(&cache->count)) {
 		WARN_ON(cache->pinned > 0);
@@ -149,22 +149,21 @@ void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
  * This adds the block group to the fs_info rb tree for the block group cache
  */
 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
-				struct btrfs_block_group_cache *block_group)
+				       struct btrfs_block_group *block_group)
 {
 	struct rb_node **p;
 	struct rb_node *parent = NULL;
-	struct btrfs_block_group_cache *cache;
+	struct btrfs_block_group *cache;
 
 	spin_lock(&info->block_group_cache_lock);
 	p = &info->block_group_cache_tree.rb_node;
 
 	while (*p) {
 		parent = *p;
-		cache = rb_entry(parent, struct btrfs_block_group_cache,
-				 cache_node);
-		if (block_group->key.objectid < cache->key.objectid) {
+		cache = rb_entry(parent, struct btrfs_block_group, cache_node);
+		if (block_group->start < cache->start) {
 			p = &(*p)->rb_left;
-		} else if (block_group->key.objectid > cache->key.objectid) {
+		} else if (block_group->start > cache->start) {
 			p = &(*p)->rb_right;
 		} else {
 			spin_unlock(&info->block_group_cache_lock);
@@ -176,8 +175,8 @@ static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
 	rb_insert_color(&block_group->cache_node,
 			&info->block_group_cache_tree);
 
-	if (info->first_logical_byte > block_group->key.objectid)
-		info->first_logical_byte = block_group->key.objectid;
+	if (info->first_logical_byte > block_group->start)
+		info->first_logical_byte = block_group->start;
 
 	spin_unlock(&info->block_group_cache_lock);
 
@@ -188,10 +187,10 @@ static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
  * This will return the block group at or after bytenr if contains is 0, else
  * it will return the block group that contains the bytenr
  */
-static struct btrfs_block_group_cache *block_group_cache_tree_search(
+static struct btrfs_block_group *block_group_cache_tree_search(
 		struct btrfs_fs_info *info, u64 bytenr, int contains)
 {
-	struct btrfs_block_group_cache *cache, *ret = NULL;
+	struct btrfs_block_group *cache, *ret = NULL;
 	struct rb_node *n;
 	u64 end, start;
 
@@ -199,13 +198,12 @@ static struct btrfs_block_group_cache *block_group_cache_tree_search(
 	n = info->block_group_cache_tree.rb_node;
 
 	while (n) {
-		cache = rb_entry(n, struct btrfs_block_group_cache,
-				 cache_node);
-		end = cache->key.objectid + cache->key.offset - 1;
-		start = cache->key.objectid;
+		cache = rb_entry(n, struct btrfs_block_group, cache_node);
+		end = cache->start + cache->length - 1;
+		start = cache->start;
 
 		if (bytenr < start) {
-			if (!contains && (!ret || start < ret->key.objectid))
+			if (!contains && (!ret || start < ret->start))
 				ret = cache;
 			n = n->rb_left;
 		} else if (bytenr > start) {
@@ -221,8 +219,8 @@ static struct btrfs_block_group_cache *block_group_cache_tree_search(
 	}
 	if (ret) {
 		btrfs_get_block_group(ret);
-		if (bytenr == 0 && info->first_logical_byte > ret->key.objectid)
-			info->first_logical_byte = ret->key.objectid;
+		if (bytenr == 0 && info->first_logical_byte > ret->start)
+			info->first_logical_byte = ret->start;
 	}
 	spin_unlock(&info->block_group_cache_lock);
 
@@ -232,7 +230,7 @@ static struct btrfs_block_group_cache *block_group_cache_tree_search(
 /*
  * Return the block group that starts at or after bytenr
  */
-struct btrfs_block_group_cache *btrfs_lookup_first_block_group(
+struct btrfs_block_group *btrfs_lookup_first_block_group(
 		struct btrfs_fs_info *info, u64 bytenr)
 {
 	return block_group_cache_tree_search(info, bytenr, 0);
@@ -241,14 +239,14 @@ struct btrfs_block_group_cache *btrfs_lookup_first_block_group(
 /*
  * Return the block group that contains the given bytenr
  */
-struct btrfs_block_group_cache *btrfs_lookup_block_group(
+struct btrfs_block_group *btrfs_lookup_block_group(
 		struct btrfs_fs_info *info, u64 bytenr)
 {
 	return block_group_cache_tree_search(info, bytenr, 1);
 }
 
-struct btrfs_block_group_cache *btrfs_next_block_group(
-		struct btrfs_block_group_cache *cache)
+struct btrfs_block_group *btrfs_next_block_group(
+		struct btrfs_block_group *cache)
 {
 	struct btrfs_fs_info *fs_info = cache->fs_info;
 	struct rb_node *node;
@@ -257,7 +255,7 @@ struct btrfs_block_group_cache *btrfs_next_block_group(
 
 	/* If our block group was removed, we need a full search. */
 	if (RB_EMPTY_NODE(&cache->cache_node)) {
-		const u64 next_bytenr = cache->key.objectid + cache->key.offset;
+		const u64 next_bytenr = cache->start + cache->length;
 
 		spin_unlock(&fs_info->block_group_cache_lock);
 		btrfs_put_block_group(cache);
@@ -266,8 +264,7 @@ struct btrfs_block_group_cache *btrfs_next_block_group(
 	node = rb_next(&cache->cache_node);
 	btrfs_put_block_group(cache);
 	if (node) {
-		cache = rb_entry(node, struct btrfs_block_group_cache,
-				 cache_node);
+		cache = rb_entry(node, struct btrfs_block_group, cache_node);
 		btrfs_get_block_group(cache);
 	} else
 		cache = NULL;
@@ -277,7 +274,7 @@ struct btrfs_block_group_cache *btrfs_next_block_group(
 
 bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)
 {
-	struct btrfs_block_group_cache *bg;
+	struct btrfs_block_group *bg;
 	bool ret = true;
 
 	bg = btrfs_lookup_block_group(fs_info, bytenr);
@@ -300,7 +297,7 @@ bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)
 
 void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)
 {
-	struct btrfs_block_group_cache *bg;
+	struct btrfs_block_group *bg;
 
 	bg = btrfs_lookup_block_group(fs_info, bytenr);
 	ASSERT(bg);
@@ -314,7 +311,7 @@ void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)
 	btrfs_put_block_group(bg);
 }
 
-void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg)
+void btrfs_wait_nocow_writers(struct btrfs_block_group *bg)
 {
 	wait_var_event(&bg->nocow_writers, !atomic_read(&bg->nocow_writers));
 }
@@ -322,7 +319,7 @@ void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg)
 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
 					const u64 start)
 {
-	struct btrfs_block_group_cache *bg;
+	struct btrfs_block_group *bg;
 
 	bg = btrfs_lookup_block_group(fs_info, start);
 	ASSERT(bg);
@@ -331,7 +328,7 @@ void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
 	btrfs_put_block_group(bg);
 }
 
-void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg)
+void btrfs_wait_block_group_reservations(struct btrfs_block_group *bg)
 {
 	struct btrfs_space_info *space_info = bg->space_info;
 
@@ -357,7 +354,7 @@ void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg)
 }
 
 struct btrfs_caching_control *btrfs_get_caching_control(
-		struct btrfs_block_group_cache *cache)
+		struct btrfs_block_group *cache)
 {
 	struct btrfs_caching_control *ctl;
 
@@ -392,7 +389,7 @@ void btrfs_put_caching_control(struct btrfs_caching_control *ctl)
  * Callers of this must check if cache->cached == BTRFS_CACHE_ERROR before using
  * any of the information in this block group.
  */
-void btrfs_wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
+void btrfs_wait_block_group_cache_progress(struct btrfs_block_group *cache,
 					   u64 num_bytes)
 {
 	struct btrfs_caching_control *caching_ctl;
@@ -401,13 +398,13 @@ void btrfs_wait_block_group_cache_progress(struct btrfs_block_group_cache *cache
 	if (!caching_ctl)
 		return;
 
-	wait_event(caching_ctl->wait, btrfs_block_group_cache_done(cache) ||
+	wait_event(caching_ctl->wait, btrfs_block_group_done(cache) ||
 		   (cache->free_space_ctl->free_space >= num_bytes));
 
 	btrfs_put_caching_control(caching_ctl);
 }
 
-int btrfs_wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
+int btrfs_wait_block_group_cache_done(struct btrfs_block_group *cache)
 {
 	struct btrfs_caching_control *caching_ctl;
 	int ret = 0;
@@ -416,7 +413,7 @@ int btrfs_wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
 	if (!caching_ctl)
 		return (cache->cached == BTRFS_CACHE_ERROR) ? -EIO : 0;
 
-	wait_event(caching_ctl->wait, btrfs_block_group_cache_done(cache));
+	wait_event(caching_ctl->wait, btrfs_block_group_done(cache));
 	if (cache->cached == BTRFS_CACHE_ERROR)
 		ret = -EIO;
 	btrfs_put_caching_control(caching_ctl);
@@ -424,11 +421,11 @@ int btrfs_wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
 }
 
 #ifdef CONFIG_BTRFS_DEBUG
-static void fragment_free_space(struct btrfs_block_group_cache *block_group)
+static void fragment_free_space(struct btrfs_block_group *block_group)
 {
 	struct btrfs_fs_info *fs_info = block_group->fs_info;
-	u64 start = block_group->key.objectid;
-	u64 len = block_group->key.offset;
+	u64 start = block_group->start;
+	u64 len = block_group->length;
 	u64 chunk = block_group->flags & BTRFS_BLOCK_GROUP_METADATA ?
 		fs_info->nodesize : fs_info->sectorsize;
 	u64 step = chunk << 1;
@@ -450,8 +447,7 @@ static void fragment_free_space(struct btrfs_block_group_cache *block_group)
  * used yet since their free space will be released as soon as the transaction
  * commits.
  */
-u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
-		       u64 start, u64 end)
+u64 add_new_free_space(struct btrfs_block_group *block_group, u64 start, u64 end)
 {
 	struct btrfs_fs_info *info = block_group->fs_info;
 	u64 extent_start, extent_end, size, total_added = 0;
@@ -491,7 +487,7 @@ u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
 
 static int load_extent_tree_free(struct btrfs_caching_control *caching_ctl)
 {
-	struct btrfs_block_group_cache *block_group = caching_ctl->block_group;
+	struct btrfs_block_group *block_group = caching_ctl->block_group;
 	struct btrfs_fs_info *fs_info = block_group->fs_info;
 	struct btrfs_root *extent_root = fs_info->extent_root;
 	struct btrfs_path *path;
@@ -507,7 +503,7 @@ static int load_extent_tree_free(struct btrfs_caching_control *caching_ctl)
 	if (!path)
 		return -ENOMEM;
 
-	last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
+	last = max_t(u64, block_group->start, BTRFS_SUPER_INFO_OFFSET);
 
 #ifdef CONFIG_BTRFS_DEBUG
 	/*
@@ -587,13 +583,12 @@ next:
 			goto next;
 		}
 
-		if (key.objectid < block_group->key.objectid) {
+		if (key.objectid < block_group->start) {
 			path->slots[0]++;
 			continue;
 		}
 
-		if (key.objectid >= block_group->key.objectid +
-		    block_group->key.offset)
+		if (key.objectid >= block_group->start + block_group->length)
 			break;
 
 		if (key.type == BTRFS_EXTENT_ITEM_KEY ||
@@ -617,8 +612,7 @@ next:
 	ret = 0;
 
 	total_found += add_new_free_space(block_group, last,
-					  block_group->key.objectid +
-					  block_group->key.offset);
+				block_group->start + block_group->length);
 	caching_ctl->progress = (u64)-1;
 
 out:
@@ -628,7 +622,7 @@ out:
 
 static noinline void caching_thread(struct btrfs_work *work)
 {
-	struct btrfs_block_group_cache *block_group;
+	struct btrfs_block_group *block_group;
 	struct btrfs_fs_info *fs_info;
 	struct btrfs_caching_control *caching_ctl;
 	int ret;
@@ -656,8 +650,7 @@ static noinline void caching_thread(struct btrfs_work *work)
 
 		spin_lock(&block_group->space_info->lock);
 		spin_lock(&block_group->lock);
-		bytes_used = block_group->key.offset -
-			btrfs_block_group_used(&block_group->item);
+		bytes_used = block_group->length - block_group->used;
 		block_group->space_info->bytes_used += bytes_used >> 1;
 		spin_unlock(&block_group->lock);
 		spin_unlock(&block_group->space_info->lock);
@@ -677,8 +670,7 @@ static noinline void caching_thread(struct btrfs_work *work)
 	btrfs_put_block_group(block_group);
 }
 
-int btrfs_cache_block_group(struct btrfs_block_group_cache *cache,
-			    int load_cache_only)
+int btrfs_cache_block_group(struct btrfs_block_group *cache, int load_cache_only)
 {
 	DEFINE_WAIT(wait);
 	struct btrfs_fs_info *fs_info = cache->fs_info;
@@ -693,10 +685,9 @@ int btrfs_cache_block_group(struct btrfs_block_group_cache *cache,
 	mutex_init(&caching_ctl->mutex);
 	init_waitqueue_head(&caching_ctl->wait);
 	caching_ctl->block_group = cache;
-	caching_ctl->progress = cache->key.objectid;
+	caching_ctl->progress = cache->start;
 	refcount_set(&caching_ctl->count, 1);
-	btrfs_init_work(&caching_ctl->work, btrfs_cache_helper,
-			caching_thread, NULL, NULL);
+	btrfs_init_work(&caching_ctl->work, caching_thread, NULL, NULL);
 
 	spin_lock(&cache->lock);
 	/*
@@ -763,8 +754,7 @@ int btrfs_cache_block_group(struct btrfs_block_group_cache *cache,
 