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| author |   David Sterba <dsterba@suse.com> | 2020-09-15 14:58:42 +0200 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2020-10-07 12:13:23 +0200 |
| commit | e97659cefe1e9dc0bb4284195ba4ab380d0cf1fe (patch) | |
| tree | 6201008f28868eb1ad4a661e330d0a4d4023bce9 | |
| parent | btrfs: free-space-cache: use unaligned helpers to access data (diff) | |
| download | linux-dev-e97659cefe1e9dc0bb4284195ba4ab380d0cf1fe.tar.xz linux-dev-e97659cefe1e9dc0bb4284195ba4ab380d0cf1fe.zip | |
btrfs: use unaligned helpers for stack and header set/get helpers
In the definitions generated by BTRFS_SETGET_HEADER_FUNCS there's direct
pointer assignment but we should use the helpers for unaligned access
for clarity. It hasn't been a problem so far because of the natural
alignment.
Similarly for BTRFS_SETGET_STACK_FUNCS, that usually get a structure
from stack that has an aligned start but some members may not be aligned
due to packing. This as well hasn't caused problems so far.
Move the put/get_unaligned_le8 stubs to ctree.h so we can use them.
Signed-off-by: David Sterba <dsterba@suse.com>
| -rw-r--r-- | fs/btrfs/ctree.h | 20 | ||||
| -rw-r--r-- | fs/btrfs/struct-funcs.c | 10 |
2 files changed, 14 insertions, 16 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index cd644c755142..5cb8af6af25d 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1420,6 +1420,16 @@ static inline void btrfs_init_map_token(struct btrfs_map_token *token, #define cpu_to_le8(v) (v) #define __le8 u8 +static inline u8 get_unaligned_le8(const void *p) +{ + return *(u8 *)p; +} + +static inline void put_unaligned_le8(u8 val, void *p) +{ + *(u8 *)p = val; +} + #define read_eb_member(eb, ptr, type, member, result) (\ read_extent_buffer(eb, (char *)(result), \ ((unsigned long)(ptr)) + \ @@ -1478,27 +1488,25 @@ static inline void btrfs_set_token_##name(struct btrfs_map_token *token,\ static inline u##bits btrfs_##name(const struct extent_buffer *eb) \ { \ const type *p = page_address(eb->pages[0]); \ - u##bits res = le##bits##_to_cpu(p->member); \ - return res; \ + return get_unaligned_le##bits(&p->member); \ } \ static inline void btrfs_set_##name(const struct extent_buffer *eb, \ u##bits val) \ { \ type *p = page_address(eb->pages[0]); \ - p->member = cpu_to_le##bits(val); \ + put_unaligned_le##bits(val, &p->member); \ } #define BTRFS_SETGET_STACK_FUNCS(name, type, member, bits) \ static inline u##bits btrfs_##name(const type *s) \ { \ - return le##bits##_to_cpu(s->member); \ + return get_unaligned_le##bits(&s->member); \ } \ static inline void btrfs_set_##name(type *s, u##bits val) \ { \ - s->member = cpu_to_le##bits(val); \ + put_unaligned_le##bits(val, &s->member); \ } - static inline u64 btrfs_device_total_bytes(const struct extent_buffer *eb, struct btrfs_dev_item *s) { diff --git a/fs/btrfs/struct-funcs.c b/fs/btrfs/struct-funcs.c index 079b059818e9..c46be27be700 100644 --- a/fs/btrfs/struct-funcs.c +++ b/fs/btrfs/struct-funcs.c @@ -7,16 +7,6 @@ #include "ctree.h" -static inline u8 get_unaligned_le8(const void *p) -{ - return *(u8 *)p; -} - -static inline void put_unaligned_le8(u8 val, void *p) -{ - *(u8 *)p = val; -} - static bool check_setget_bounds(const struct extent_buffer *eb, const void *ptr, unsigned off, int size) { |