From 2fe1d55134fce05c17ea118a2e37a4af771887bc Mon Sep 17 00:00:00 2001 From: Omar Sandoval Date: Thu, 22 Sep 2016 17:24:20 -0700 Subject: Btrfs: fix free space tree bitmaps on big-endian systems MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In convert_free_space_to_{bitmaps,extents}(), we buffer the free space bitmaps in memory and copy them directly to/from the extent buffers with {read,write}_extent_buffer(). The extent buffer bitmap helpers use byte granularity, which is equivalent to a little-endian bitmap. This means that on big-endian systems, the in-memory bitmaps will be written to disk byte-swapped. To fix this, use byte-granularity for the bitmaps in memory. Fixes: a5ed91828518 ("Btrfs: implement the free space B-tree") Cc: stable@vger.kernel.org # 4.5+ Tested-by: Holger Hoffstätte Tested-by: Chandan Rajendra Signed-off-by: Omar Sandoval Signed-off-by: David Sterba --- fs/btrfs/free-space-tree.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) (limited to 'fs/btrfs/free-space-tree.c') diff --git a/fs/btrfs/free-space-tree.c b/fs/btrfs/free-space-tree.c index 87e7e3d3e676..8fd85bfbe2da 100644 --- a/fs/btrfs/free-space-tree.c +++ b/fs/btrfs/free-space-tree.c @@ -151,7 +151,7 @@ static inline u32 free_space_bitmap_size(u64 size, u32 sectorsize) return DIV_ROUND_UP((u32)div_u64(size, sectorsize), BITS_PER_BYTE); } -static unsigned long *alloc_bitmap(u32 bitmap_size) +static u8 *alloc_bitmap(u32 bitmap_size) { void *mem; @@ -180,8 +180,7 @@ int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans, struct btrfs_free_space_info *info; struct btrfs_key key, found_key; struct extent_buffer *leaf; - unsigned long *bitmap; - char *bitmap_cursor; + u8 *bitmap, *bitmap_cursor; u64 start, end; u64 bitmap_range, i; u32 bitmap_size, flags, expected_extent_count; @@ -231,7 +230,7 @@ int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans, block_group->sectorsize); last = div_u64(found_key.objectid + found_key.offset - start, block_group->sectorsize); - bitmap_set(bitmap, first, last - first); + le_bitmap_set(bitmap, first, last - first); extent_count++; nr++; @@ -269,7 +268,7 @@ int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans, goto out; } - bitmap_cursor = (char *)bitmap; + bitmap_cursor = bitmap; bitmap_range = block_group->sectorsize * BTRFS_FREE_SPACE_BITMAP_BITS; i = start; while (i < end) { @@ -318,7 +317,7 @@ int convert_free_space_to_extents(struct btrfs_trans_handle *trans, struct btrfs_free_space_info *info; struct btrfs_key key, found_key; struct extent_buffer *leaf; - unsigned long *bitmap; + u8 *bitmap; u64 start, end; /* Initialize to silence GCC. */ u64 extent_start = 0; @@ -362,7 +361,7 @@ int convert_free_space_to_extents(struct btrfs_trans_handle *trans, break; } else if (found_key.type == BTRFS_FREE_SPACE_BITMAP_KEY) { unsigned long ptr; - char *bitmap_cursor; + u8 *bitmap_cursor; u32 bitmap_pos, data_size; ASSERT(found_key.objectid >= start); @@ -372,7 +371,7 @@ int convert_free_space_to_extents(struct btrfs_trans_handle *trans, bitmap_pos = div_u64(found_key.objectid - start, block_group->sectorsize * BITS_PER_BYTE); - bitmap_cursor = ((char *)bitmap) + bitmap_pos; + bitmap_cursor = bitmap + bitmap_pos; data_size = free_space_bitmap_size(found_key.offset, block_group->sectorsize); @@ -409,7 +408,7 @@ int convert_free_space_to_extents(struct btrfs_trans_handle *trans, offset = start; bitnr = 0; while (offset < end) { - bit = !!test_bit(bitnr, bitmap); + bit = !!le_test_bit(bitnr, bitmap); if (prev_bit == 0 && bit == 1) { extent_start = offset; } else if (prev_bit == 1 && bit == 0) { -- cgit v1.2.3