diff options
author | Jeff Mahoney <jeffm@suse.com> | 2017-06-28 21:56:53 -0600 |
---|---|---|
committer | David Sterba <dsterba@suse.com> | 2017-08-16 14:19:53 +0200 |
commit | 1cbb1f454e5321e47fc1e6b233066c7ccc979d15 (patch) | |
tree | 574441acf725ed6fc7dc370c0c1d298989051981 /fs/btrfs/ctree.h | |
parent | 23d1f73788785a770fe6eb348fee4b26281d2064 (diff) | |
download | linux-1cbb1f454e5321e47fc1e6b233066c7ccc979d15.tar.bz2 |
btrfs: struct-funcs, constify readers
We have reader helpers for most of the on-disk structures that use
an extent_buffer and pointer as offset into the buffer that are
read-only. We should mark them as const and, in turn, allow consumers
of these interfaces to mark the buffers const as well.
No impact on code, but serves as documentation that a buffer is intended
not to be modified.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/ctree.h')
-rw-r--r-- | fs/btrfs/ctree.h | 128 |
1 files changed, 66 insertions, 62 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 589491040950..34ed3dabd43a 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1434,7 +1434,7 @@ do { \ #define BTRFS_INODE_ROOT_ITEM_INIT (1 << 31) struct btrfs_map_token { - struct extent_buffer *eb; + const struct extent_buffer *eb; char *kaddr; unsigned long offset; }; @@ -1468,18 +1468,19 @@ static inline void btrfs_init_map_token (struct btrfs_map_token *token) sizeof(((type *)0)->member))) #define DECLARE_BTRFS_SETGET_BITS(bits) \ -u##bits btrfs_get_token_##bits(struct extent_buffer *eb, void *ptr, \ - unsigned long off, \ - struct btrfs_map_token *token); \ -void btrfs_set_token_##bits(struct extent_buffer *eb, void *ptr, \ +u##bits btrfs_get_token_##bits(const struct extent_buffer *eb, \ + const void *ptr, unsigned long off, \ + struct btrfs_map_token *token); \ +void btrfs_set_token_##bits(struct extent_buffer *eb, const void *ptr, \ unsigned long off, u##bits val, \ struct btrfs_map_token *token); \ -static inline u##bits btrfs_get_##bits(struct extent_buffer *eb, void *ptr, \ +static inline u##bits btrfs_get_##bits(const struct extent_buffer *eb, \ + const void *ptr, \ unsigned long off) \ { \ return btrfs_get_token_##bits(eb, ptr, off, NULL); \ } \ -static inline void btrfs_set_##bits(struct extent_buffer *eb, void *ptr, \ +static inline void btrfs_set_##bits(struct extent_buffer *eb, void *ptr,\ unsigned long off, u##bits val) \ { \ btrfs_set_token_##bits(eb, ptr, off, val, NULL); \ @@ -1491,7 +1492,8 @@ DECLARE_BTRFS_SETGET_BITS(32) DECLARE_BTRFS_SETGET_BITS(64) #define BTRFS_SETGET_FUNCS(name, type, member, bits) \ -static inline u##bits btrfs_##name(struct extent_buffer *eb, type *s) \ +static inline u##bits btrfs_##name(const struct extent_buffer *eb, \ + const type *s) \ { \ BUILD_BUG_ON(sizeof(u##bits) != sizeof(((type *)0))->member); \ return btrfs_get_##bits(eb, s, offsetof(type, member)); \ @@ -1502,7 +1504,8 @@ static inline void btrfs_set_##name(struct extent_buffer *eb, type *s, \ BUILD_BUG_ON(sizeof(u##bits) != sizeof(((type *)0))->member); \ btrfs_set_##bits(eb, s, offsetof(type, member), val); \ } \ -static inline u##bits btrfs_token_##name(struct extent_buffer *eb, type *s, \ +static inline u##bits btrfs_token_##name(const struct extent_buffer *eb,\ + const type *s, \ struct btrfs_map_token *token) \ { \ BUILD_BUG_ON(sizeof(u##bits) != sizeof(((type *)0))->member); \ @@ -1517,9 +1520,9 @@ static inline void btrfs_set_token_##name(struct extent_buffer *eb, \ } #define BTRFS_SETGET_HEADER_FUNCS(name, type, member, bits) \ -static inline u##bits btrfs_##name(struct extent_buffer *eb) \ +static inline u##bits btrfs_##name(const struct extent_buffer *eb) \ { \ - type *p = page_address(eb->pages[0]); \ + const type *p = page_address(eb->pages[0]); \ u##bits res = le##bits##_to_cpu(p->member); \ return res; \ } \ @@ -1531,7 +1534,7 @@ static inline void btrfs_set_##name(struct extent_buffer *eb, \ } #define BTRFS_SETGET_STACK_FUNCS(name, type, member, bits) \ -static inline u##bits btrfs_##name(type *s) \ +static inline u##bits btrfs_##name(const type *s) \ { \ return le##bits##_to_cpu(s->member); \ } \ @@ -1856,7 +1859,7 @@ static inline unsigned long btrfs_node_key_ptr_offset(int nr) sizeof(struct btrfs_key_ptr) * nr; } -void btrfs_node_key(struct extent_buffer *eb, +void btrfs_node_key(const struct extent_buffer *eb, struct btrfs_disk_key *disk_key, int nr); static inline void btrfs_set_node_key(struct extent_buffer *eb, @@ -1885,28 +1888,28 @@ static inline struct btrfs_item *btrfs_item_nr(int nr) return (struct btrfs_item *)btrfs_item_nr_offset(nr); } -static inline u32 btrfs_item_end(struct extent_buffer *eb, +static inline u32 btrfs_item_end(const struct extent_buffer *eb, struct btrfs_item *item) { return btrfs_item_offset(eb, item) + btrfs_item_size(eb, item); } -static inline u32 btrfs_item_end_nr(struct extent_buffer *eb, int nr) +static inline u32 btrfs_item_end_nr(const struct extent_buffer *eb, int nr) { return btrfs_item_end(eb, btrfs_item_nr(nr)); } -static inline u32 btrfs_item_offset_nr(struct extent_buffer *eb, int nr) +static inline u32 btrfs_item_offset_nr(const struct extent_buffer *eb, int nr) { return btrfs_item_offset(eb, btrfs_item_nr(nr)); } -static inline u32 btrfs_item_size_nr(struct extent_buffer *eb, int nr) +static inline u32 btrfs_item_size_nr(const struct extent_buffer *eb, int nr) { return btrfs_item_size(eb, btrfs_item_nr(nr)); } -static inline void btrfs_item_key(struct extent_buffer *eb, +static inline void btrfs_item_key(const struct extent_buffer *eb, struct btrfs_disk_key *disk_key, int nr) { struct btrfs_item *item = btrfs_item_nr(nr); @@ -1942,8 +1945,8 @@ BTRFS_SETGET_STACK_FUNCS(stack_dir_name_len, struct btrfs_dir_item, BTRFS_SETGET_STACK_FUNCS(stack_dir_transid, struct btrfs_dir_item, transid, 64); -static inline void btrfs_dir_item_key(struct extent_buffer *eb, - struct btrfs_dir_item *item, +static inline void btrfs_dir_item_key(const struct extent_buffer *eb, + const struct btrfs_dir_item *item, struct btrfs_disk_key *key) { read_eb_member(eb, item, struct btrfs_dir_item, location, key); @@ -1951,7 +1954,7 @@ static inline void btrfs_dir_item_key(struct extent_buffer *eb, static inline void btrfs_set_dir_item_key(struct extent_buffer *eb, struct btrfs_dir_item *item, - struct btrfs_disk_key *key) + const struct btrfs_disk_key *key) { write_eb_member(eb, item, struct btrfs_dir_item, location, key); } @@ -1963,8 +1966,8 @@ BTRFS_SETGET_FUNCS(free_space_bitmaps, struct btrfs_free_space_header, BTRFS_SETGET_FUNCS(free_space_generation, struct btrfs_free_space_header, generation, 64); -static inline void btrfs_free_space_key(struct extent_buffer *eb, - struct btrfs_free_space_header *h, +static inline void btrfs_free_space_key(const struct extent_buffer *eb, + const struct btrfs_free_space_header *h, struct btrfs_disk_key *key) { read_eb_member(eb, h, struct btrfs_free_space_header, location, key); @@ -1972,7 +1975,7 @@ static inline void btrfs_free_space_key(struct extent_buffer *eb, static inline void btrfs_set_free_space_key(struct extent_buffer *eb, struct btrfs_free_space_header *h, - struct btrfs_disk_key *key) + const struct btrfs_disk_key *key) { write_eb_member(eb, h, struct btrfs_free_space_header, location, key); } @@ -1999,25 +2002,25 @@ static inline void btrfs_cpu_key_to_disk(struct btrfs_disk_key *disk, disk->objectid = cpu_to_le64(cpu->objectid); } -static inline void btrfs_node_key_to_cpu(struct extent_buffer *eb, - struct btrfs_key *key, int nr) +static inline void btrfs_node_key_to_cpu(const struct extent_buffer *eb, + struct btrfs_key *key, int nr) { struct btrfs_disk_key disk_key; btrfs_node_key(eb, &disk_key, nr); btrfs_disk_key_to_cpu(key, &disk_key); } -static inline void btrfs_item_key_to_cpu(struct extent_buffer *eb, - struct btrfs_key *key, int nr) +static inline void btrfs_item_key_to_cpu(const struct extent_buffer *eb, + struct btrfs_key *key, int nr) { struct btrfs_disk_key disk_key; btrfs_item_key(eb, &disk_key, nr); btrfs_disk_key_to_cpu(key, &disk_key); } -static inline void btrfs_dir_item_key_to_cpu(struct extent_buffer *eb, - struct btrfs_dir_item *item, - struct btrfs_key *key) +static inline void btrfs_dir_item_key_to_cpu(const struct extent_buffer *eb, + const struct btrfs_dir_item *item, + struct btrfs_key *key) { struct btrfs_disk_key disk_key; btrfs_dir_item_key(eb, item, &disk_key); @@ -2049,7 +2052,7 @@ BTRFS_SETGET_STACK_FUNCS(stack_header_nritems, struct btrfs_header, nritems, 32); BTRFS_SETGET_STACK_FUNCS(stack_header_bytenr, struct btrfs_header, bytenr, 64); -static inline int btrfs_header_flag(struct extent_buffer *eb, u64 flag) +static inline int btrfs_header_flag(const struct extent_buffer *eb, u64 flag) { return (btrfs_header_flags(eb) & flag) == flag; } @@ -2068,7 +2071,7 @@ static inline int btrfs_clear_header_flag(struct extent_buffer *eb, u64 flag) return (flags & flag) == flag; } -static inline int btrfs_header_backref_rev(struct extent_buffer *eb) +static inline int btrfs_header_backref_rev(const struct extent_buffer *eb) { u64 flags = btrfs_header_flags(eb); return flags >> BTRFS_BACKREF_REV_SHIFT; @@ -2088,12 +2091,12 @@ static inline unsigned long btrfs_header_fsid(void) return offsetof(struct btrfs_header, fsid); } -static inline unsigned long btrfs_header_chunk_tree_uuid(struct extent_buffer *eb) +static inline unsigned long btrfs_header_chunk_tree_uuid(const struct extent_buffer *eb) { return offsetof(struct btrfs_header, chunk_tree_uuid); } -static inline int btrfs_is_leaf(struct extent_buffer *eb) +static inline int btrfs_is_leaf(const struct extent_buffer *eb) { return btrfs_header_level(eb) == 0; } @@ -2127,12 +2130,12 @@ BTRFS_SETGET_STACK_FUNCS(root_stransid, struct btrfs_root_item, BTRFS_SETGET_STACK_FUNCS(root_rtransid, struct btrfs_root_item, rtransid, 64); -static inline bool btrfs_root_readonly(struct btrfs_root *root) +static inline bool btrfs_root_readonly(const struct btrfs_root *root) { return (root->root_item.flags & cpu_to_le64(BTRFS_ROOT_SUBVOL_RDONLY)) != 0; } -static inline bool btrfs_root_dead(struct btrfs_root *root) +static inline bool btrfs_root_dead(const struct btrfs_root *root) { return (root->root_item.flags & cpu_to_le64(BTRFS_ROOT_SUBVOL_DEAD)) != 0; } @@ -2189,51 +2192,51 @@ BTRFS_SETGET_STACK_FUNCS(backup_num_devices, struct btrfs_root_backup, /* struct btrfs_balance_item */ BTRFS_SETGET_FUNCS(balance_flags, struct btrfs_balance_item, flags, 64); -static inline void btrfs_balance_data(struct extent_buffer *eb, - struct btrfs_balance_item *bi, +static inline void btrfs_balance_data(const struct extent_buffer *eb, + const struct btrfs_balance_item *bi, struct btrfs_disk_balance_args *ba) { read_eb_member(eb, bi, struct btrfs_balance_item, data, ba); } static inline void btrfs_set_balance_data(struct extent_buffer *eb, - struct btrfs_balance_item *bi, - struct btrfs_disk_balance_args *ba) + struct btrfs_balance_item *bi, + const struct btrfs_disk_balance_args *ba) { write_eb_member(eb, bi, struct btrfs_balance_item, data, ba); } -static inline void btrfs_balance_meta(struct extent_buffer *eb, - struct btrfs_balance_item *bi, +static inline void btrfs_balance_meta(const struct extent_buffer *eb, + const struct btrfs_balance_item *bi, struct btrfs_disk_balance_args *ba) { read_eb_member(eb, bi, struct btrfs_balance_item, meta, ba); } static inline void btrfs_set_balance_meta(struct extent_buffer *eb, - struct btrfs_balance_item *bi, - struct btrfs_disk_balance_args *ba) + struct btrfs_balance_item *bi, + const struct btrfs_disk_balance_args *ba) { write_eb_member(eb, bi, struct btrfs_balance_item, meta, ba); } -static inline void btrfs_balance_sys(struct extent_buffer *eb, - struct btrfs_balance_item *bi, +static inline void btrfs_balance_sys(const struct extent_buffer *eb, + const struct btrfs_balance_item *bi, struct btrfs_disk_balance_args *ba) { read_eb_member(eb, bi, struct btrfs_balance_item, sys, ba); } static inline void btrfs_set_balance_sys(struct extent_buffer *eb, - struct btrfs_balance_item *bi, - struct btrfs_disk_balance_args *ba) + struct btrfs_balance_item *bi, + const struct btrfs_disk_balance_args *ba) { write_eb_member(eb, bi, struct btrfs_balance_item, sys, ba); } static inline void btrfs_disk_balance_args_to_cpu(struct btrfs_balance_args *cpu, - struct btrfs_disk_balance_args *disk) + const struct btrfs_disk_balance_args *disk) { memset(cpu, 0, sizeof(*cpu)); @@ -2253,7 +2256,7 @@ btrfs_disk_balance_args_to_cpu(struct btrfs_balance_args *cpu, static inline void btrfs_cpu_balance_args_to_disk(struct btrfs_disk_balance_args *disk, - struct btrfs_balance_args *cpu) + const struct btrfs_balance_args *cpu) { memset(disk, 0, sizeof(*disk)); @@ -2321,7 +2324,7 @@ BTRFS_SETGET_STACK_FUNCS(super_magic, struct btrfs_super_block, magic, 64); BTRFS_SETGET_STACK_FUNCS(super_uuid_tree_generation, struct btrfs_super_block, uuid_tree_generation, 64); -static inline int btrfs_super_csum_size(struct btrfs_super_block *s) +static inline int btrfs_super_csum_size(const struct btrfs_super_block *s) { u16 t = btrfs_super_csum_type(s); /* @@ -2336,8 +2339,8 @@ static inline int btrfs_super_csum_size(struct btrfs_super_block *s) * this returns the address of the start of the last item, * which is the stop of the leaf data stack */ -static inline unsigned int leaf_data_end(struct btrfs_fs_info *fs_info, - struct extent_buffer *leaf) +static inline unsigned int leaf_data_end(const struct btrfs_fs_info *fs_info, + const struct extent_buffer *leaf) { u32 nr = btrfs_header_nritems(leaf); @@ -2362,7 +2365,7 @@ BTRFS_SETGET_STACK_FUNCS(stack_file_extent_compression, struct btrfs_file_extent_item, compression, 8); static inline unsigned long -btrfs_file_extent_inline_start(struct btrfs_file_extent_item *e) +btrfs_file_extent_inline_start(const struct btrfs_file_extent_item *e) { return (unsigned long)e + BTRFS_FILE_EXTENT_INLINE_DATA_START; } @@ -2396,8 +2399,9 @@ BTRFS_SETGET_FUNCS(file_extent_other_encoding, struct btrfs_file_extent_item, * size of any extent headers. If a file is compressed on disk, this is * the compressed size */ -static inline u32 btrfs_file_extent_inline_item_len(struct extent_buffer *eb, - struct btrfs_item *e) +static inline u32 btrfs_file_extent_inline_item_len( + const struct extent_buffer *eb, + struct btrfs_item *e) { return btrfs_item_size(eb, e) - BTRFS_FILE_EXTENT_INLINE_DATA_START; } @@ -2405,9 +2409,9 @@ static inline u32 btrfs_file_extent_inline_item_len(struct extent_buffer *eb, /* this returns the number of file bytes represented by the inline item. * If an item is compressed, this is the uncompressed size */ -static inline u32 btrfs_file_extent_inline_len(struct extent_buffer *eb, - int slot, - struct btrfs_file_extent_item *fi) +static inline u32 btrfs_file_extent_inline_len(const struct extent_buffer *eb, + int slot, + const struct btrfs_file_extent_item *fi) { struct btrfs_map_token token; @@ -2429,8 +2433,8 @@ static inline u32 btrfs_file_extent_inline_len(struct extent_buffer *eb, /* btrfs_dev_stats_item */ -static inline u64 btrfs_dev_stats_value(struct extent_buffer *eb, - struct btrfs_dev_stats_item *ptr, +static inline u64 btrfs_dev_stats_value(const struct extent_buffer *eb, + const struct btrfs_dev_stats_item *ptr, int index) { u64 val; |