diff options
Diffstat (limited to 'fs/xfs/xfs_attr_leaf.h')
| -rw-r--r-- | fs/xfs/xfs_attr_leaf.h | 230 |
1 files changed, 0 insertions, 230 deletions
diff --git a/fs/xfs/xfs_attr_leaf.h b/fs/xfs/xfs_attr_leaf.h index da34e64b532..3ec5ec0b867 100644 --- a/fs/xfs/xfs_attr_leaf.h +++ b/fs/xfs/xfs_attr_leaf.h @@ -19,16 +19,6 @@ #ifndef __XFS_ATTR_LEAF_H__ #define __XFS_ATTR_LEAF_H__ -/* - * Attribute storage layout, internal structure, access macros, etc. - * - * Attribute lists are structured around Btrees where all the data - * elements are in the leaf nodes. Attribute names are hashed into an int, - * then that int is used as the index into the Btree. Since the hashval - * of an attribute name may not be unique, we may have duplicate keys. The - * internal links in the Btree are logical block offsets into the file. - */ - struct attrlist; struct attrlist_cursor_kern; struct xfs_attr_list_context; @@ -38,226 +28,6 @@ struct xfs_da_state_blk; struct xfs_inode; struct xfs_trans; -/*======================================================================== - * Attribute structure when equal to XFS_LBSIZE(mp) bytes. - *========================================================================*/ - -/* - * This is the structure of the leaf nodes in the Btree. - * - * Struct leaf_entry's are packed from the top. Name/values grow from the - * bottom but are not packed. The freemap contains run-length-encoded entries - * for the free bytes after the leaf_entry's, but only the N largest such, - * smaller runs are dropped. When the freemap doesn't show enough space - * for an allocation, we compact the name/value area and try again. If we - * still don't have enough space, then we have to split the block. The - * name/value structs (both local and remote versions) must be 32bit aligned. - * - * Since we have duplicate hash keys, for each key that matches, compare - * the actual name string. The root and intermediate node search always - * takes the first-in-the-block key match found, so we should only have - * to work "forw"ard. If none matches, continue with the "forw"ard leaf - * nodes until the hash key changes or the attribute name is found. - * - * We store the fact that an attribute is a ROOT/USER/SECURE attribute in - * the leaf_entry. The namespaces are independent only because we also look - * at the namespace bit when we are looking for a matching attribute name. - * - * We also store an "incomplete" bit in the leaf_entry. It shows that an - * attribute is in the middle of being created and should not be shown to - * the user if we crash during the time that the bit is set. We clear the - * bit when we have finished setting up the attribute. We do this because - * we cannot create some large attributes inside a single transaction, and we - * need some indication that we weren't finished if we crash in the middle. - */ -#define XFS_ATTR_LEAF_MAPSIZE 3 /* how many freespace slots */ - -typedef struct xfs_attr_leaf_map { /* RLE map of free bytes */ - __be16 base; /* base of free region */ - __be16 size; /* length of free region */ -} xfs_attr_leaf_map_t; - -typedef struct xfs_attr_leaf_hdr { /* constant-structure header block */ - xfs_da_blkinfo_t info; /* block type, links, etc. */ - __be16 count; /* count of active leaf_entry's */ - __be16 usedbytes; /* num bytes of names/values stored */ - __be16 firstused; /* first used byte in name area */ - __u8 holes; /* != 0 if blk needs compaction */ - __u8 pad1; - xfs_attr_leaf_map_t freemap[XFS_ATTR_LEAF_MAPSIZE]; - /* N largest free regions */ -} xfs_attr_leaf_hdr_t; - -typedef struct xfs_attr_leaf_entry { /* sorted on key, not name */ - __be32 hashval; /* hash value of name */ - __be16 nameidx; /* index into buffer of name/value */ - __u8 flags; /* LOCAL/ROOT/SECURE/INCOMPLETE flag */ - __u8 pad2; /* unused pad byte */ -} xfs_attr_leaf_entry_t; - -typedef struct xfs_attr_leaf_name_local { - __be16 valuelen; /* number of bytes in value */ - __u8 namelen; /* length of name bytes */ - __u8 nameval[1]; /* name/value bytes */ -} xfs_attr_leaf_name_local_t; - -typedef struct xfs_attr_leaf_name_remote { - __be32 valueblk; /* block number of value bytes */ - __be32 valuelen; /* number of bytes in value */ - __u8 namelen; /* length of name bytes */ - __u8 name[1]; /* name bytes */ -} xfs_attr_leaf_name_remote_t; - -typedef struct xfs_attr_leafblock { - xfs_attr_leaf_hdr_t hdr; /* constant-structure header block */ - xfs_attr_leaf_entry_t entries[1]; /* sorted on key, not name */ - xfs_attr_leaf_name_local_t namelist; /* grows from bottom of buf */ - xfs_attr_leaf_name_remote_t valuelist; /* grows from bottom of buf */ -} xfs_attr_leafblock_t; - -/* - * CRC enabled leaf structures. Called "version 3" structures to match the - * version number of the directory and dablk structures for this feature, and - * attr2 is already taken by the variable inode attribute fork size feature. - */ -struct xfs_attr3_leaf_hdr { - struct xfs_da3_blkinfo info; - __be16 count; - __be16 usedbytes; - __be16 firstused; - __u8 holes; - __u8 pad1; - struct xfs_attr_leaf_map freemap[XFS_ATTR_LEAF_MAPSIZE]; - __be32 pad2; /* 64 bit alignment */ -}; - -#define XFS_ATTR3_LEAF_CRC_OFF (offsetof(struct xfs_attr3_leaf_hdr, info.crc)) - -struct xfs_attr3_leafblock { - struct xfs_attr3_leaf_hdr hdr; - struct xfs_attr_leaf_entry entries[1]; - - /* - * The rest of the block contains the following structures after the - * leaf entries, growing from the bottom up. The variables are never - * referenced, the locations accessed purely from helper functions. - * - * struct xfs_attr_leaf_name_local - * struct xfs_attr_leaf_name_remote - */ -}; - -/* - * incore, neutral version of the attribute leaf header - */ -struct xfs_attr3_icleaf_hdr { - __uint32_t forw; - __uint32_t back; - __uint16_t magic; - __uint16_t count; - __uint16_t usedbytes; - __uint16_t firstused; - __u8 holes; - struct { - __uint16_t base; - __uint16_t size; - } freemap[XFS_ATTR_LEAF_MAPSIZE]; -}; - -/* - * Flags used in the leaf_entry[i].flags field. - * NOTE: the INCOMPLETE bit must not collide with the flags bits specified - * on the system call, they are "or"ed together for various operations. - */ -#define XFS_ATTR_LOCAL_BIT 0 /* attr is stored locally */ -#define XFS_ATTR_ROOT_BIT 1 /* limit access to trusted attrs */ -#define XFS_ATTR_SECURE_BIT 2 /* limit access to secure attrs */ -#define XFS_ATTR_INCOMPLETE_BIT 7 /* attr in middle of create/delete */ -#define XFS_ATTR_LOCAL (1 << XFS_ATTR_LOCAL_BIT) -#define XFS_ATTR_ROOT (1 << XFS_ATTR_ROOT_BIT) -#define XFS_ATTR_SECURE (1 << XFS_ATTR_SECURE_BIT) -#define XFS_ATTR_INCOMPLETE (1 << XFS_ATTR_INCOMPLETE_BIT) - -/* - * Conversion macros for converting namespace bits from argument flags - * to ondisk flags. - */ -#define XFS_ATTR_NSP_ARGS_MASK (ATTR_ROOT | ATTR_SECURE) -#define XFS_ATTR_NSP_ONDISK_MASK (XFS_ATTR_ROOT | XFS_ATTR_SECURE) -#define XFS_ATTR_NSP_ONDISK(flags) ((flags) & XFS_ATTR_NSP_ONDISK_MASK) -#define XFS_ATTR_NSP_ARGS(flags) ((flags) & XFS_ATTR_NSP_ARGS_MASK) -#define XFS_ATTR_NSP_ARGS_TO_ONDISK(x) (((x) & ATTR_ROOT ? XFS_ATTR_ROOT : 0) |\ - ((x) & ATTR_SECURE ? XFS_ATTR_SECURE : 0)) -#define XFS_ATTR_NSP_ONDISK_TO_ARGS(x) (((x) & XFS_ATTR_ROOT ? ATTR_ROOT : 0) |\ - ((x) & XFS_ATTR_SECURE ? ATTR_SECURE : 0)) - -/* - * Alignment for namelist and valuelist entries (since they are mixed - * there can be only one alignment value) - */ -#define XFS_ATTR_LEAF_NAME_ALIGN ((uint)sizeof(xfs_dablk_t)) - -static inline int -xfs_attr3_leaf_hdr_size(struct xfs_attr_leafblock *leafp) -{ - if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) - return sizeof(struct xfs_attr3_leaf_hdr); - return sizeof(struct xfs_attr_leaf_hdr); -} - -static inline struct xfs_attr_leaf_entry * -xfs_attr3_leaf_entryp(xfs_attr_leafblock_t *leafp) -{ - if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) - return &((struct xfs_attr3_leafblock *)leafp)->entries[0]; - return &leafp->entries[0]; -} - -/* - * Cast typed pointers for "local" and "remote" name/value structs. - */ -static inline char * -xfs_attr3_leaf_name(xfs_attr_leafblock_t *leafp, int idx) -{ - struct xfs_attr_leaf_entry *entries = xfs_attr3_leaf_entryp(leafp); - - return &((char *)leafp)[be16_to_cpu(entries[idx].nameidx)]; -} - -static inline xfs_attr_leaf_name_remote_t * -xfs_attr3_leaf_name_remote(xfs_attr_leafblock_t *leafp, int idx) -{ - return (xfs_attr_leaf_name_remote_t *)xfs_attr3_leaf_name(leafp, idx); -} - -static inline xfs_attr_leaf_name_local_t * -xfs_attr3_leaf_name_local(xfs_attr_leafblock_t *leafp, int idx) -{ - return (xfs_attr_leaf_name_local_t *)xfs_attr3_leaf_name(leafp, idx); -} - -/* - * Calculate total bytes used (including trailing pad for alignment) for - * a "local" name/value structure, a "remote" name/value structure, and - * a pointer which might be either. - */ -static inline int xfs_attr_leaf_entsize_remote(int nlen) -{ - return ((uint)sizeof(xfs_attr_leaf_name_remote_t) - 1 + (nlen) + \ - XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1); -} - -static inline int xfs_attr_leaf_entsize_local(int nlen, int vlen) -{ - return ((uint)sizeof(xfs_attr_leaf_name_local_t) - 1 + (nlen) + (vlen) + - XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1); -} - -static inline int xfs_attr_leaf_entsize_local_max(int bsize) -{ - return (((bsize) >> 1) + ((bsize) >> 2)); -} - /* * Used to keep a list of "remote value" extents when unlinking an inode. */ |