ref: 733c5d6645b133b60d304c38fcb1398f94d0618c
dir: /sys/src/cmd/ext4srv/include/ext4_extent.h/
#pragma once #include "ext4_config.h" #include "ext4_types.h" #include "ext4_misc.h" #include "ext4_inode.h" /* * 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_extent_path { struct ext4_block block; u16int depth; struct ext4_extent_header *header; struct ext4_extent_index *index; struct ext4_extent *extent; }; #define EXT4_EXT_UNWRITTEN_MASK (1L << 15) #define EXT4_EXT_MAX_LEN_WRITTEN (1L << 15) #define EXT4_EXT_MAX_LEN_UNWRITTEN \ (EXT4_EXT_MAX_LEN_WRITTEN - 1) #define EXT4_EXT_GET_LEN(ex) to_le16((ex)->nblocks) #define EXT4_EXT_GET_LEN_UNWRITTEN(ex) \ (EXT4_EXT_GET_LEN(ex) & ~(EXT4_EXT_UNWRITTEN_MASK)) #define EXT4_EXT_SET_LEN(ex, count) \ ((ex)->nblocks = to_le16(count)) #define EXT4_EXT_IS_UNWRITTEN(ex) \ (EXT4_EXT_GET_LEN(ex) > EXT4_EXT_MAX_LEN_WRITTEN) #define EXT4_EXT_SET_UNWRITTEN(ex) \ ((ex)->nblocks |= to_le16(EXT4_EXT_UNWRITTEN_MASK)) #define EXT4_EXT_SET_WRITTEN(ex) \ ((ex)->nblocks &= ~(to_le16(EXT4_EXT_UNWRITTEN_MASK))) #define EXT4_EXTENT_FIRST(header) \ ((struct ext4_extent *)(((char *)(header)) + \ sizeof(struct ext4_extent_header))) #define EXT4_EXTENT_FIRST_INDEX(header) \ ((struct ext4_extent_index *)(((char *)(header)) + \ sizeof(struct ext4_extent_header))) #define EXT4_EXTENT_LAST(header) \ ((struct ext4_extent *)(((char *)(header)) + \ sizeof(struct ext4_extent_header)) + \ (header)->nentries - 1) #define EXT4_EXTENT_LAST_INDEX(header) \ ((struct ext4_extent_index *)(((char *)(header)) + \ sizeof(struct ext4_extent_header)) + \ (header)->nentries - 1) #define EXT4_EXTENT_SIZE sizeof(struct ext4_extent) #define EXT4_EXTENT_INDEX_SIZE sizeof(struct ext4_extent_index) #define EXT4_EXTENT_TAIL_OFFSET(hdr) \ (sizeof(struct ext4_extent_header) + \ (sizeof(struct ext4_extent) * to_le16((hdr)->max_nentries))) #define EXT4_EXTENT_IN_RANGE(iblock, eiblock, len) \ ((iblock) >= (eiblock) && (iblock) <= (eiblock) + (len) - 1) #define EXT4_EXTENT_MAX_BLOCKS ((u32int)(-1)) /**@brief Get logical number of the block covered by extent. * @param extent Extent to load number from * @return Logical number of the first block covered by extent */ static inline u32int ext4_extent_get_iblock(struct ext4_extent *extent) { return to_le32(extent->iblock); } /**@brief Set logical number of the first block covered by extent. * @param extent Extent to set number to * @param iblock Logical number of the first block covered by extent */ static inline void ext4_extent_set_iblock(struct ext4_extent *extent, ext4_lblk_t iblock) { extent->iblock = to_le32(iblock); } /**@brief Get number of blocks covered by extent. * @param extent Extent to load count from * @return Number of blocks covered by extent */ static inline u16int ext4_extent_get_nblocks(struct ext4_extent *extent) { if (EXT4_EXT_IS_UNWRITTEN(extent)) return EXT4_EXT_GET_LEN_UNWRITTEN(extent); else return EXT4_EXT_GET_LEN(extent); } /**@brief Set number of blocks covered by extent. * @param extent Extent to load count from * @param count Number of blocks covered by extent * @param unwritten Whether the extent is unwritten or not */ static inline void ext4_extent_set_nblocks(struct ext4_extent *extent, u16int count, bool unwritten) { EXT4_EXT_SET_LEN(extent, count); if (unwritten) EXT4_EXT_SET_UNWRITTEN(extent); } /**@brief Get physical number of the first block covered by extent. * @param extent Extent to load number * @return Physical number of the first block covered by extent */ static inline u64int ext4_extent_get_fblock(struct ext4_extent *extent) { return ((u64int)to_le16(extent->fblock_hi)) << 32 | ((u64int)to_le32(extent->fblock_lo)); } /**@brief Set physical number of the first block covered by extent. * @param extent Extent to load number * @param fblock Physical number of the first block covered by extent */ static inline void ext4_extent_set_fblock(struct ext4_extent *extent, u64int fblock) { extent->fblock_lo = to_le32((fblock << 32) >> 32); extent->fblock_hi = to_le16((u16int)(fblock >> 32)); } /**@brief Get logical number of the block covered by extent index. * @param index Extent index to load number from * @return Logical number of the first block covered by extent index */ static inline u32int ext4_extent_index_get_iblock(struct ext4_extent_index *index) { return to_le32(index->iblock); } /**@brief Set logical number of the block covered by extent index. * @param index Extent index to set number to * @param iblock Logical number of the first block covered by extent index */ static inline void ext4_extent_index_set_iblock(struct ext4_extent_index *index, u32int iblock) { index->iblock = to_le32(iblock); } /**@brief Get physical number of block where the child node is located. * @param index Extent index to load number from * @return Physical number of the block with child node */ static inline u64int ext4_extent_index_get_fblock(struct ext4_extent_index *index) { return ((u64int)to_le16(index->fblock_hi)) << 32 | ((u64int)to_le32(index->fblock_lo)); } /**@brief Set physical number of block where the child node is located. * @param index Extent index to set number to * @param fblock Ohysical number of the block with child node */ static inline void ext4_extent_index_set_fblock(struct ext4_extent_index *index, u64int fblock) { index->fblock_lo = to_le32((fblock << 32) >> 32); index->fblock_hi = to_le16((u16int)(fblock >> 32)); } /**@brief Get magic value from extent header. * @param header Extent header to load value from * @return Magic value of extent header */ static inline u16int ext4_extent_header_get_magic(struct ext4_extent_header *header) { return to_le16(header->magic); } /**@brief Set magic value to extent header. * @param header Extent header to set value to * @param magic Magic value of extent header */ static inline void ext4_extent_header_set_magic(struct ext4_extent_header *header, u16int magic) { header->magic = to_le16(magic); } /**@brief Get number of entries from extent header * @param header Extent header to get value from * @return Number of entries covered by extent header */ static inline u16int ext4_extent_header_get_nentries(struct ext4_extent_header *header) { return to_le16(header->nentries); } /**@brief Set number of entries to extent header * @param header Extent header to set value to * @param count Number of entries covered by extent header */ static inline void ext4_extent_header_set_nentries(struct ext4_extent_header *header, u16int count) { header->nentries = to_le16(count); } /**@brief Get maximum number of entries from extent header * @param header Extent header to get value from * @return Maximum number of entries covered by extent header */ static inline u16int ext4_extent_header_get_max_nentries(struct ext4_extent_header *header) { return to_le16(header->max_nentries); } /**@brief Set maximum number of entries to extent header * @param header Extent header to set value to * @param max_count Maximum number of entries covered by extent header */ static inline void ext4_extent_header_set_max_nentries(struct ext4_extent_header *header, u16int max_count) { header->max_nentries = to_le16(max_count); } /**@brief Get depth of extent subtree. * @param header Extent header to get value from * @return Depth of extent subtree */ static inline u16int ext4_extent_header_get_depth(struct ext4_extent_header *header) { return to_le16(header->depth); } /**@brief Set depth of extent subtree. * @param header Extent header to set value to * @param depth Depth of extent subtree */ static inline void ext4_extent_header_set_depth(struct ext4_extent_header *header, u16int depth) { header->depth = to_le16(depth); } /**@brief Get generation from extent header * @param header Extent header to get value from * @return Generation */ static inline u32int ext4_extent_header_get_generation(struct ext4_extent_header *header) { return to_le32(header->generation); } /**@brief Set generation to extent header * @param header Extent header to set value to * @param generation Generation */ static inline void ext4_extent_header_set_generation(struct ext4_extent_header *header, u32int generation) { header->generation = to_le32(generation); } /******************************************************************************/ /**TODO: */ static inline void ext4_extent_tree_init(struct ext4_inode_ref *inode_ref) { /* Initialize extent root header */ struct ext4_extent_header *header = ext4_inode_get_extent_header(inode_ref->inode); ext4_extent_header_set_depth(header, 0); ext4_extent_header_set_nentries(header, 0); ext4_extent_header_set_generation(header, 0); ext4_extent_header_set_magic(header, EXT4_EXTENT_MAGIC); u16int max_entries = (EXT4_INODE_BLOCKS * sizeof(u32int) - sizeof(struct ext4_extent_header)) / sizeof(struct ext4_extent); ext4_extent_header_set_max_nentries(header, max_entries); inode_ref->dirty = true; } /**@brief Extent-based blockmap manipulation * @param inode_ref I-node * @param iblock starting logical block of the inode * @param max_nblocks maximum number of blocks to get from/allocate to blockmap * @param resfblockp return physical block address of the first block of an * extent * @param create true if caller wants to insert mapping or convert * unwritten mapping to written one * @param resnblocksp return number of blocks in an extent (must be smaller than * \p max_nblocks) * @return Error code*/ int ext4_extent_get_blocks(struct ext4_inode_ref *inode_ref, ext4_lblk_t iblock, ext4_lblk_t max_nblocks, ext4_fsblk_t *resfblockp, bool create, ext4_lblk_t *resnblocksp); /**@brief Release all data blocks starting from specified logical block. * @param inode_ref I-node to release blocks from * @param iblock_from First logical block to release * @return Error code */ int ext4_extent_remove_space(struct ext4_inode_ref *inode_ref, ext4_lblk_t from, ext4_lblk_t to);