[PULL][PATCH 0/4] Btrfs: cleanups for 4.5, part 2

[PULL][PATCH 0/4] Btrfs: cleanups for 4.5, part 2

[David Sterba]

Hi,

a handful of cleanups. Geliang Tang's patch is a fixup to his list iterator cleanup,
Jeff's patch has been posted long time ago. Please pull to 4.5.

----------------------------------------------------------------
The following changes since commit a7ca42256d9fad572fb7f2c471514d7d3572b1db:

  btrfs: use list_for_each_entry* in backref.c (2016-01-07 14:42:46 +0100)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git misc-cleanups-4.5

for you to fetch changes up to fb75d857a31d600cc0c37b8c7d914014f7fa3f9a:

  btrfs: remove duplicate const specifier (2016-01-19 10:33:56 +0100)

----------------------------------------------------------------
Colin Ian King (1):
  btrfs: remove duplicate const specifier

Dan Carpenter (1):
  Btrfs: clean up an error code in btrfs_init_space_info()

Geliang Tang (1):
  btrfs: fix iterator with update error in backref.c

Jeff Mahoney (1):
  btrfs: cleanup, stop casting for extent_map->lookup everywhere

 fs/btrfs/backref.c     | 10 +++++-----
 fs/btrfs/dev-replace.c |  2 +-
 fs/btrfs/extent-tree.c |  4 ++--
 fs/btrfs/extent_map.c  |  2 +-
 fs/btrfs/extent_map.h  | 10 +++++++++-
 fs/btrfs/scrub.c       |  2 +-
 fs/btrfs/volumes.c     | 26 +++++++++++++-------------
 7 files changed, 32 insertions(+), 24 deletions(-)

-- 
2.6.3

[PATCH 1/4] btrfs: cleanup, stop casting for extent_map->lookup everywhere

[David Sterba]

From: Jeff Mahoney <jeffm@suse.com>

Overloading extent_map->bdev to struct map_lookup * might have started out
as a means to an end, but it's a pattern that's used all over the place
now. Let's get rid of the casting and just add a union instead.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/dev-replace.c |  2 +-
 fs/btrfs/extent-tree.c |  2 +-
 fs/btrfs/extent_map.c  |  2 +-
 fs/btrfs/extent_map.h  | 10 +++++++++-
 fs/btrfs/scrub.c       |  2 +-
 fs/btrfs/volumes.c     | 24 ++++++++++++------------
 6 files changed, 25 insertions(+), 17 deletions(-)

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 1e668fb7dd4c..cbb7dbfb3fff 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -614,7 +614,7 @@ static void btrfs_dev_replace_update_device_in_mapping_tree(
 		em = lookup_extent_mapping(em_tree, start, (u64)-1);
 		if (!em)
 			break;
-		map = (struct map_lookup *)em->bdev;
+		map = em->map_lookup;
 		for (i = 0; i < map->num_stripes; i++)
 			if (srcdev == map->stripes[i].dev)
 				map->stripes[i].dev = tgtdev;
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 1ea56d8bfd3e..8c912894a5bd 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -10322,7 +10322,7 @@ btrfs_start_trans_remove_block_group(struct btrfs_fs_info *fs_info,
 	 * more device items and remove one chunk item), but this is done at
 	 * btrfs_remove_chunk() through a call to check_system_chunk().
 	 */
-	map = (struct map_lookup *)em->bdev;
+	map = em->map_lookup;
 	num_items = 3 + map->num_stripes;
 	free_extent_map(em);
 
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 6a98bddd8f33..84fb56d5c018 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -76,7 +76,7 @@ void free_extent_map(struct extent_map *em)
 		WARN_ON(extent_map_in_tree(em));
 		WARN_ON(!list_empty(&em->list));
 		if (test_bit(EXTENT_FLAG_FS_MAPPING, &em->flags))
-			kfree(em->bdev);
+			kfree(em->map_lookup);
 		kmem_cache_free(extent_map_cache, em);
 	}
 }
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index b2991fd8583e..eb8b8fae036b 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -32,7 +32,15 @@ struct extent_map {
 	u64 block_len;
 	u64 generation;
 	unsigned long flags;
-	struct block_device *bdev;
+	union {
+		struct block_device *bdev;
+
+		/*
+		 * used for chunk mappings
+		 * flags & EXTENT_FLAG_FS_MAPPING must be set
+		 */
+		struct map_lookup *map_lookup;
+	};
 	atomic_t refs;
 	unsigned int compress_type;
 	struct list_head list;
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index b57a15a523a4..151000f6b66d 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -3458,7 +3458,7 @@ static noinline_for_stack int scrub_chunk(struct scrub_ctx *sctx,
 		return ret;
 	}
 
-	map = (struct map_lookup *)em->bdev;
+	map = em->map_lookup;
 	if (em->start != chunk_offset)
 		goto out;
 
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index adb79ad33d38..9cb78e31fc76 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1182,7 +1182,7 @@ static int contains_pending_extent(struct btrfs_transaction *transaction,
 		struct map_lookup *map;
 		int i;
 
-		map = (struct map_lookup *)em->bdev;
+		map = em->map_lookup;
 		for (i = 0; i < map->num_stripes; i++) {
 			u64 end;
 
@@ -2754,7 +2754,7 @@ int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
 			free_extent_map(em);
 		return -EINVAL;
 	}
-	map = (struct map_lookup *)em->bdev;
+	map = em->map_lookup;
 	lock_chunks(root->fs_info->chunk_root);
 	check_system_chunk(trans, extent_root, map->type);
 	unlock_chunks(root->fs_info->chunk_root);
@@ -4718,7 +4718,7 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 		goto error;
 	}
 	set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
-	em->bdev = (struct block_device *)map;
+	em->map_lookup = map;
 	em->start = start;
 	em->len = num_bytes;
 	em->block_start = 0;
@@ -4813,7 +4813,7 @@ int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
 		return -EINVAL;
 	}
 
-	map = (struct map_lookup *)em->bdev;
+	map = em->map_lookup;
 	item_size = btrfs_chunk_item_size(map->num_stripes);
 	stripe_size = em->orig_block_len;
 
@@ -4955,7 +4955,7 @@ int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
 	if (!em)
 		return 1;
 
-	map = (struct map_lookup *)em->bdev;
+	map = em->map_lookup;
 	for (i = 0; i < map->num_stripes; i++) {
 		if (map->stripes[i].dev->missing) {
 			miss_ndevs++;
@@ -5035,7 +5035,7 @@ int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
 		return 1;
 	}
 
-	map = (struct map_lookup *)em->bdev;
+	map = em->map_lookup;
 	if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
 		ret = map->num_stripes;
 	else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
@@ -5071,7 +5071,7 @@ unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
 	BUG_ON(!em);
 
 	BUG_ON(em->start > logical || em->start + em->len < logical);
-	map = (struct map_lookup *)em->bdev;
+	map = em->map_lookup;
 	if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
 		len = map->stripe_len * nr_data_stripes(map);
 	free_extent_map(em);
@@ -5092,7 +5092,7 @@ int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
 	BUG_ON(!em);
 
 	BUG_ON(em->start > logical || em->start + em->len < logical);
-	map = (struct map_lookup *)em->bdev;
+	map = em->map_lookup;
 	if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
 		ret = 1;
 	free_extent_map(em);
@@ -5251,7 +5251,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 		return -EINVAL;
 	}
 
-	map = (struct map_lookup *)em->bdev;
+	map = em->map_lookup;
 	offset = logical - em->start;
 
 	stripe_len = map->stripe_len;
@@ -5793,7 +5793,7 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
 		free_extent_map(em);
 		return -EIO;
 	}
-	map = (struct map_lookup *)em->bdev;
+	map = em->map_lookup;
 
 	length = em->len;
 	rmap_len = map->stripe_len;
@@ -6229,7 +6229,7 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
 	}
 
 	set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
-	em->bdev = (struct block_device *)map;
+	em->map_lookup = map;
 	em->start = logical;
 	em->len = length;
 	em->orig_start = 0;
@@ -6920,7 +6920,7 @@ void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
 	/* In order to kick the device replace finish process */
 	lock_chunks(root);
 	list_for_each_entry(em, &transaction->pending_chunks, list) {
-		map = (struct map_lookup *)em->bdev;
+		map = em->map_lookup;
 
 		for (i = 0; i < map->num_stripes; i++) {
 			dev = map->stripes[i].dev;
-- 
2.6.3

[PATCH 2/4] btrfs: fix iterator with update error in backref.c

[David Sterba]

From: Geliang Tang <geliangtang@163.com>

Fix the following error:

fs/btrfs/backref.c:565:1-20: iterator with update on line 577

Fixes: a7ca422('btrfs: use list_for_each_entry* in backref.c')
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/backref.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 08405a3da6b1..b90cd3776f8e 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -560,13 +560,13 @@ static int __add_missing_keys(struct btrfs_fs_info *fs_info,
  */
 static void __merge_refs(struct list_head *head, int mode)
 {
-	struct __prelim_ref *ref1;
+	struct __prelim_ref *pos1;
 
-	list_for_each_entry(ref1, head, list) {
-		struct __prelim_ref *ref2 = ref1, *tmp;
+	list_for_each_entry(pos1, head, list) {
+		struct __prelim_ref *pos2 = pos1, *tmp;
 
-		list_for_each_entry_safe_continue(ref2, tmp, head, list) {
-			struct __prelim_ref *xchg;
+		list_for_each_entry_safe_continue(pos2, tmp, head, list) {
+			struct __prelim_ref *xchg, *ref1 = pos1, *ref2 = pos2;
 			struct extent_inode_elem *eie;
 
 			if (!ref_for_same_block(ref1, ref2))
-- 
2.6.3

[PATCH 3/4] Btrfs: clean up an error code in btrfs_init_space_info()

[David Sterba]

From: Dan Carpenter <dan.carpenter@oracle.com>

If we return 1 here, then the caller treats it as an error and returns
-EINVAL.  It causes a static checker warning to treat positive returns
as an error.

Fixes: 1aba86d67f34 ('Btrfs: fix easily get into ENOSPC in mixed case')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/extent-tree.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 8c912894a5bd..9d70330c6ebf 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -10509,7 +10509,7 @@ int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
 
 	disk_super = fs_info->super_copy;
 	if (!btrfs_super_root(disk_super))
-		return 1;
+		return -EINVAL;
 
 	features = btrfs_super_incompat_flags(disk_super);
 	if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
-- 
2.6.3

[PATCH 4/4] btrfs: remove duplicate const specifier

[David Sterba]

From: Colin Ian King <colin.king@canonical.com>

duplicate const is redundant so remove it

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/volumes.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 9cb78e31fc76..78f76958b855 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -108,7 +108,7 @@ const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
 	},
 };
 
-const u64 const btrfs_raid_group[BTRFS_NR_RAID_TYPES] = {
+const u64 btrfs_raid_group[BTRFS_NR_RAID_TYPES] = {
 	[BTRFS_RAID_RAID10] = BTRFS_BLOCK_GROUP_RAID10,
 	[BTRFS_RAID_RAID1]  = BTRFS_BLOCK_GROUP_RAID1,
 	[BTRFS_RAID_DUP]    = BTRFS_BLOCK_GROUP_DUP,
-- 
2.6.3