+++ /dev/null
-#ifndef _LINUX_EXT4_EXT
-#define _LINUX_EXT4_EXT
-
-/*
- * 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 {
- uint32_t et_checksum; /* crc32c(uuid+inum+extent_block) */
-};
-
-/*
- * This is the extent on-disk structure.
- * It's used at the bottom of the tree.
- */
-typedef struct ext4_extent {
- uint32_t ee_block; /* first logical block extent covers */
- uint16_t ee_len; /* number of blocks covered by extent */
- uint16_t ee_start_hi; /* high 16 bits of physical block */
- uint32_t ee_start_lo; /* low 32 bits of physical block */
-} __attribute__ ((__packed__)) EXT4_EXTENT;
-
-/*
- * This is index on-disk structure.
- * It's used at all the levels except the bottom.
- */
-typedef struct ext4_extent_idx {
- uint32_t ei_block; /* index covers logical blocks from 'block' */
- uint32_t ei_leaf_lo; /* pointer to the physical block of the next *
- * level. leaf or next index could be there */
- uint16_t ei_leaf_hi; /* high 16 bits of physical block */
- uint16_t ei_unused;
-}__attribute__ ((__packed__)) EXT4_EXTENT_IDX;
-
-/*
- * Each block (leaves and indexes), even inode-stored has header.
- */
-typedef struct ext4_extent_header {
- uint16_t eh_magic; /* probably will support different formats */
- uint16_t eh_entries; /* number of valid entries */
- uint16_t eh_max; /* capacity of store in entries */
- uint16_t eh_depth; /* has tree real underlying blocks? */
- uint32_t eh_generation; /* generation of the tree */
-}__attribute__ ((__packed__)) EXT4_EXTENT_HEADER;
-
-
-#define EXT4_EXT_MAGIC 0xf30a
-#define get_ext4_header(i) ((struct ext4_extent_header *) (i)->i_block)
-
-#define EXT4_EXTENT_TAIL_OFFSET(hdr) \
- (sizeof(struct ext4_extent_header) + \
- (sizeof(struct ext4_extent) * (hdr)->eh_max))
-
-static inline struct ext4_extent_tail *
-find_ext4_extent_tail(struct ext4_extent_header *eh)
-{
- return (struct ext4_extent_tail *)(((char *)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.
- * Truncate uses it to simulate recursive walking.
- */
-struct ext4_ext_path
-{
- ext4_fsblk_t p_block;
- int p_depth;
- int p_maxdepth;
- struct ext4_extent *p_ext;
- struct ext4_extent_idx *p_idx;
- struct ext4_extent_header *p_hdr;
- struct buffer_head *p_bh;
-};
-
-/*
- * structure for external API
- */
-
-/*
- * 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.
- * preallocated).
- * EXT_UNINIT_MAX_LEN is the maximum number of blocks we can have in an
- * uninitialized 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
- * 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).
- */
-#define EXT_INIT_MAX_LEN (1UL << 15)
-#define EXT_UNWRITTEN_MAX_LEN (EXT_INIT_MAX_LEN - 1)
-
-#define EXT_EXTENT_SIZE sizeof(struct ext4_extent)
-#define EXT_INDEX_SIZE sizeof(struct ext4_extent_idx)
-
-#define EXT_FIRST_EXTENT(__hdr__) \
- ((struct ext4_extent *)(((char *)(__hdr__)) + \
- sizeof(struct ext4_extent_header)))
-#define EXT_FIRST_INDEX(__hdr__) \
- ((struct ext4_extent_idx *)(((char *)(__hdr__)) + \
- sizeof(struct ext4_extent_header)))
-#define EXT_HAS_FREE_INDEX(__path__) \
- ((__path__)->p_hdr->eh_entries < (__path__)->p_hdr->eh_max)
-#define EXT_LAST_EXTENT(__hdr__) \
- (EXT_FIRST_EXTENT((__hdr__)) + (__hdr__)->eh_entries - 1)
-#define EXT_LAST_INDEX(__hdr__) \
- (EXT_FIRST_INDEX((__hdr__)) + (__hdr__)->eh_entries - 1)
-#define EXT_MAX_EXTENT(__hdr__) \
- (EXT_FIRST_EXTENT((__hdr__)) + (__hdr__)->eh_max - 1)
-#define EXT_MAX_INDEX(__hdr__) \
- (EXT_FIRST_INDEX((__hdr__)) + (__hdr__)->eh_max - 1)
-
-static inline struct ext4_extent_header *ext_inode_hdr(struct inode *inode)
-{
- return get_ext4_header(inode);
-}
-
-static inline struct ext4_extent_header *ext_block_hdr(struct buffer_head *bh)
-{
- return (struct ext4_extent_header *)bh->b_data;
-}
-
-static inline unsigned short ext_depth(struct inode *inode)
-{
- return ext_inode_hdr(inode)->eh_depth;
-}
-
-static inline void ext4_ext_mark_uninitialized(struct ext4_extent *ext)
-{
- /* We can not have an uninitialized extent of zero length! */
- ext->ee_len |= EXT_INIT_MAX_LEN;
-}
-
-static inline int ext4_ext_is_uninitialized(struct ext4_extent *ext)
-{
- /* Extent with ee_len of 0x8000 is treated as an initialized extent */
- return (ext->ee_len > EXT_INIT_MAX_LEN);
-}
-
-static inline uint16_t ext4_ext_get_actual_len(struct ext4_extent *ext)
-{
- return (ext->ee_len <= EXT_INIT_MAX_LEN
- ? ext->ee_len
- : (ext->ee_len - EXT_INIT_MAX_LEN));
-}
-
-static inline void ext4_ext_mark_initialized(struct ext4_extent *ext)
-{
- ext->ee_len = ext4_ext_get_actual_len(ext);
-}
-
-static inline void ext4_ext_mark_unwritten(struct ext4_extent *ext)
-{
- /* We can not have an unwritten extent of zero length! */
- ext->ee_len |= EXT_INIT_MAX_LEN;
-}
-
-static inline int ext4_ext_is_unwritten(struct ext4_extent *ext)
-{
- /* Extent with ee_len of 0x8000 is treated as an initialized extent */
- return (ext->ee_len > EXT_INIT_MAX_LEN);
-}
-
-/*
- * 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 = ex->ee_start_lo;
- block |= ((ext4_fsblk_t)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 = ix->ei_leaf_lo;
- block |= ((ext4_fsblk_t)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 = (uint32_t)(pb & 0xffffffff);
- ex->ee_start_hi = (uint16_t)((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 = (uint32_t)(pb & 0xffffffff);
- ix->ei_leaf_hi = (uint16_t)((pb >> 31) >> 1) & 0xffff;
-}
-
-#define ext4_ext_dirty(icb, handle, inode, path) \
- __ext4_ext_dirty("", __LINE__, (icb), (handle), (inode), (path))
-
-#define INODE_HAS_EXTENT(i) ((i)->i_flags & EXT2_EXTENTS_FL)
-
-static inline uint64_t ext_to_block(EXT4_EXTENT *extent)
-{
- uint64_t block;
-
- block = (uint64_t)extent->ee_start_lo;
- block |= ((uint64_t) extent->ee_start_hi << 31) << 1;
-
- return block;
-}
-
-static inline uint64_t idx_to_block(EXT4_EXTENT_IDX *idx)
-{
- uint64_t block;
-
- block = (uint64_t)idx->ei_leaf_lo;
- block |= ((uint64_t) idx->ei_leaf_hi << 31) << 1;
-
- return block;
-}
-
-
-int ext4_ext_get_blocks(void *icb, handle_t *handle, struct inode *inode, ext4_fsblk_t iblock,
- unsigned long max_blocks, struct buffer_head *bh_result,
- int create, int flags);
-int ext4_ext_tree_init(void *icb, handle_t *handle, struct inode *inode);
-int ext4_ext_truncate(void *icb, struct inode *inode, unsigned long start);
-
-#endif /* _LINUX_EXT4_EXT */