diff options
Diffstat (limited to 'fs/ext4/ext4_extents.h')
| -rw-r--r-- | fs/ext4/ext4_extents.h | 167 |
1 files changed, 92 insertions, 75 deletions
diff --git a/fs/ext4/ext4_extents.h b/fs/ext4/ext4_extents.h index bdb6ce7e2eb..a867f5ca999 100644 --- a/fs/ext4/ext4_extents.h +++ b/fs/ext4/ext4_extents.h @@ -43,16 +43,6 @@ #define CHECK_BINSEARCH__ /* - * Turn on EXT_DEBUG to get lots of info about extents operations. - */ -#define EXT_DEBUG__ -#ifdef EXT_DEBUG -#define ext_debug(a...) printk(a) -#else -#define ext_debug(a...) -#endif - -/* * If EXT_STATS is defined then stats numbers are collected. * These number will be displayed at umount time. */ @@ -63,9 +53,22 @@ * ext4_inode has i_block array (60 bytes total). * The first 12 bytes store ext4_extent_header; * the remainder stores an array of ext4_extent. + * For non-inode extent blocks, ext4_extent_tail + * follows the array. */ /* + * This is the extent tail on-disk structure. + * All other extent structures are 12 bytes long. It turns out that + * block_size % 12 >= 4 for at least all powers of 2 greater than 512, which + * covers all valid ext4 block sizes. Therefore, this tail structure can be + * crammed into the end of the block without having to rebalance the tree. + */ +struct ext4_extent_tail { + __le32 et_checksum; /* crc32c(uuid+inum+extent_block) */ +}; + +/* * This is the extent on-disk structure. * It's used at the bottom of the tree. */ @@ -101,6 +104,17 @@ struct ext4_extent_header { #define EXT4_EXT_MAGIC cpu_to_le16(0xf30a) +#define EXT4_EXTENT_TAIL_OFFSET(hdr) \ + (sizeof(struct ext4_extent_header) + \ + (sizeof(struct ext4_extent) * le16_to_cpu((hdr)->eh_max))) + +static inline struct ext4_extent_tail * +find_ext4_extent_tail(struct ext4_extent_header *eh) +{ + return (struct ext4_extent_tail *)(((void *)eh) + + EXT4_EXTENT_TAIL_OFFSET(eh)); +} + /* * Array of ext4_ext_path contains path to some extent. * Creation/lookup routines use it for traversal/splitting/etc. @@ -119,46 +133,25 @@ struct ext4_ext_path { * structure for external API */ -#define EXT4_EXT_CACHE_NO 0 -#define EXT4_EXT_CACHE_GAP 1 -#define EXT4_EXT_CACHE_EXTENT 2 - -/* - * to be called by ext4_ext_walk_space() - * negative retcode - error - * positive retcode - signal for ext4_ext_walk_space(), see below - * callback must return valid extent (passed or newly created) - */ -typedef int (*ext_prepare_callback)(struct inode *, struct ext4_ext_path *, - struct ext4_ext_cache *, - struct ext4_extent *, void *); - -#define EXT_CONTINUE 0 -#define EXT_BREAK 1 -#define EXT_REPEAT 2 - -/* Maximum logical block in a file; ext4_extent's ee_block is __le32 */ -#define EXT_MAX_BLOCK 0xffffffff - /* * EXT_INIT_MAX_LEN is the maximum number of blocks we can have in an * initialized extent. This is 2^15 and not (2^16 - 1), since we use the * MSB of ee_len field in the extent datastructure to signify if this - * particular extent is an initialized extent or an uninitialized (i.e. + * particular extent is an initialized extent or an unwritten (i.e. * preallocated). - * EXT_UNINIT_MAX_LEN is the maximum number of blocks we can have in an - * uninitialized extent. + * EXT_UNWRITTEN_MAX_LEN is the maximum number of blocks we can have in an + * unwritten extent. * If ee_len is <= 0x8000, it is an initialized extent. Otherwise, it is an - * uninitialized one. In other words, if MSB of ee_len is set, it is an - * uninitialized extent with only one special scenario when ee_len = 0x8000. - * In this case we can not have an uninitialized extent of zero length and + * unwritten one. In other words, if MSB of ee_len is set, it is an + * unwritten extent with only one special scenario when ee_len = 0x8000. + * In this case we can not have an unwritten extent of zero length and * thus we make it as a special case of initialized extent with 0x8000 length. * This way we get better extent-to-group alignment for initialized extents. * Hence, the maximum number of blocks we can have in an *initialized* - * extent is 2^15 (32768) and in an *uninitialized* extent is 2^15-1 (32767). + * extent is 2^15 (32768) and in an *unwritten* extent is 2^15-1 (32767). */ #define EXT_INIT_MAX_LEN (1UL << 15) -#define EXT_UNINIT_MAX_LEN (EXT_INIT_MAX_LEN - 1) +#define EXT_UNWRITTEN_MAX_LEN (EXT_INIT_MAX_LEN - 1) #define EXT_FIRST_EXTENT(__hdr__) \ @@ -194,20 +187,14 @@ static inline unsigned short ext_depth(struct inode *inode) return le16_to_cpu(ext_inode_hdr(inode)->eh_depth); } -static inline void -ext4_ext_invalidate_cache(struct inode *inode) +static inline void ext4_ext_mark_unwritten(struct ext4_extent *ext) { - EXT4_I(inode)->i_cached_extent.ec_type = EXT4_EXT_CACHE_NO; -} - -static inline void ext4_ext_mark_uninitialized(struct ext4_extent *ext) -{ - /* We can not have an uninitialized extent of zero length! */ + /* We can not have an unwritten extent of zero length! */ BUG_ON((le16_to_cpu(ext->ee_len) & ~EXT_INIT_MAX_LEN) == 0); ext->ee_len |= cpu_to_le16(EXT_INIT_MAX_LEN); } -static inline int ext4_ext_is_uninitialized(struct ext4_extent *ext) +static inline int ext4_ext_is_unwritten(struct ext4_extent *ext) { /* Extent with ee_len of 0x8000 is treated as an initialized extent */ return (le16_to_cpu(ext->ee_len) > EXT_INIT_MAX_LEN); @@ -225,32 +212,62 @@ static inline void ext4_ext_mark_initialized(struct ext4_extent *ext) ext->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ext)); } -extern int ext4_ext_calc_metadata_amount(struct inode *inode, - sector_t lblocks); -extern ext4_fsblk_t ext_pblock(struct ext4_extent *ex); -extern ext4_fsblk_t idx_pblock(struct ext4_extent_idx *); -extern void ext4_ext_store_pblock(struct ext4_extent *, ext4_fsblk_t); -extern int ext4_extent_tree_init(handle_t *, struct inode *); -extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode, - int num, - struct ext4_ext_path *path); -extern int ext4_can_extents_be_merged(struct inode *inode, - struct ext4_extent *ex1, - struct ext4_extent *ex2); -extern int ext4_ext_try_to_merge(struct inode *inode, - struct ext4_ext_path *path, - struct ext4_extent *); -extern unsigned int ext4_ext_check_overlap(struct inode *, struct ext4_extent *, struct ext4_ext_path *); -extern int ext4_ext_insert_extent(handle_t *, struct inode *, struct ext4_ext_path *, struct ext4_extent *, int); -extern int ext4_ext_walk_space(struct inode *, ext4_lblk_t, ext4_lblk_t, - ext_prepare_callback, void *); -extern struct ext4_ext_path *ext4_ext_find_extent(struct inode *, ext4_lblk_t, - struct ext4_ext_path *); -extern int ext4_ext_search_left(struct inode *, struct ext4_ext_path *, - ext4_lblk_t *, ext4_fsblk_t *); -extern int ext4_ext_search_right(struct inode *, struct ext4_ext_path *, - ext4_lblk_t *, ext4_fsblk_t *); -extern void ext4_ext_drop_refs(struct ext4_ext_path *); -extern int ext4_ext_check_inode(struct inode *inode); +/* + * ext4_ext_pblock: + * combine low and high parts of physical block number into ext4_fsblk_t + */ +static inline ext4_fsblk_t ext4_ext_pblock(struct ext4_extent *ex) +{ + ext4_fsblk_t block; + + block = le32_to_cpu(ex->ee_start_lo); + block |= ((ext4_fsblk_t) le16_to_cpu(ex->ee_start_hi) << 31) << 1; + return block; +} + +/* + * ext4_idx_pblock: + * combine low and high parts of a leaf physical block number into ext4_fsblk_t + */ +static inline ext4_fsblk_t ext4_idx_pblock(struct ext4_extent_idx *ix) +{ + ext4_fsblk_t block; + + block = le32_to_cpu(ix->ei_leaf_lo); + block |= ((ext4_fsblk_t) le16_to_cpu(ix->ei_leaf_hi) << 31) << 1; + return block; +} + +/* + * ext4_ext_store_pblock: + * stores a large physical block number into an extent struct, + * breaking it into parts + */ +static inline void ext4_ext_store_pblock(struct ext4_extent *ex, + ext4_fsblk_t pb) +{ + ex->ee_start_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff)); + ex->ee_start_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & + 0xffff); +} + +/* + * ext4_idx_store_pblock: + * stores a large physical block number into an index struct, + * breaking it into parts + */ +static inline void ext4_idx_store_pblock(struct ext4_extent_idx *ix, + ext4_fsblk_t pb) +{ + ix->ei_leaf_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff)); + ix->ei_leaf_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & + 0xffff); +} + +#define ext4_ext_dirty(handle, inode, path) \ + __ext4_ext_dirty(__func__, __LINE__, (handle), (inode), (path)) +int __ext4_ext_dirty(const char *where, unsigned int line, handle_t *handle, + struct inode *inode, struct ext4_ext_path *path); + #endif /* _EXT4_EXTENTS */ |