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| author |   David Sterba <dsterba@suse.com> | 2020-09-15 13:32:34 +0200 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2020-10-07 12:13:23 +0200 |
| commit | 6994ca367ce5160dea2718e0993542d148fa68f8 (patch) | |
| tree | c1daf574e8a649711c3b94fbf8385ced6e7af8d3 /fs/btrfs | |
| parent | btrfs: send: use helpers for unaligned access to header members (diff) | |
| download | linux-dev-6994ca367ce5160dea2718e0993542d148fa68f8.tar.xz linux-dev-6994ca367ce5160dea2718e0993542d148fa68f8.zip | |
btrfs: free-space-cache: use unaligned helpers to access data
The free space inode stores the tracking data, checksums etc, using the
io_ctl structure and moving the pointers. The data are generally aligned
to at least 4 bytes (u32 for CRC) so it's not completely unaligned but
for clarity we should use the proper helpers whenever a struct is
initialized from io_ctl->cur pointer.
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs')
| -rw-r--r-- | fs/btrfs/free-space-cache.c | 21 |
1 files changed, 9 insertions, 12 deletions
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index 8759f5a1d6a0..af0013d3df63 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -413,8 +413,6 @@ static int io_ctl_prepare_pages(struct btrfs_io_ctl *io_ctl, bool uptodate) static void io_ctl_set_generation(struct btrfs_io_ctl *io_ctl, u64 generation) { - __le64 *val; - io_ctl_map_page(io_ctl, 1); /* @@ -429,14 +427,13 @@ static void io_ctl_set_generation(struct btrfs_io_ctl *io_ctl, u64 generation) io_ctl->size -= sizeof(u64) * 2; } - val = io_ctl->cur; - *val = cpu_to_le64(generation); + put_unaligned_le64(generation, io_ctl->cur); io_ctl->cur += sizeof(u64); } static int io_ctl_check_generation(struct btrfs_io_ctl *io_ctl, u64 generation) { - __le64 *gen; + u64 cache_gen; /* * Skip the crc area. If we don't check crcs then we just have a 64bit @@ -451,11 +448,11 @@ static int io_ctl_check_generation(struct btrfs_io_ctl *io_ctl, u64 generation) io_ctl->size -= sizeof(u64) * 2; } - gen = io_ctl->cur; - if (le64_to_cpu(*gen) != generation) { + cache_gen = get_unaligned_le64(io_ctl->cur); + if (cache_gen != generation) { btrfs_err_rl(io_ctl->fs_info, "space cache generation (%llu) does not match inode (%llu)", - *gen, generation); + cache_gen, generation); io_ctl_unmap_page(io_ctl); return -EIO; } @@ -525,8 +522,8 @@ static int io_ctl_add_entry(struct btrfs_io_ctl *io_ctl, u64 offset, u64 bytes, return -ENOSPC; entry = io_ctl->cur; - entry->offset = cpu_to_le64(offset); - entry->bytes = cpu_to_le64(bytes); + put_unaligned_le64(offset, &entry->offset); + put_unaligned_le64(bytes, &entry->bytes); entry->type = (bitmap) ? BTRFS_FREE_SPACE_BITMAP : BTRFS_FREE_SPACE_EXTENT; io_ctl->cur += sizeof(struct btrfs_free_space_entry); @@ -599,8 +596,8 @@ static int io_ctl_read_entry(struct btrfs_io_ctl *io_ctl, } e = io_ctl->cur; - entry->offset = le64_to_cpu(e->offset); - entry->bytes = le64_to_cpu(e->bytes); + entry->offset = get_unaligned_le64(&e->offset); + entry->bytes = get_unaligned_le64(&e->bytes); *type = e->type; io_ctl->cur += sizeof(struct btrfs_free_space_entry); io_ctl->size -= sizeof(struct btrfs_free_space_entry); |