diff options
Diffstat (limited to 'fs/xfs/libxfs/xfs_da_format.h')
| -rw-r--r-- | fs/xfs/libxfs/xfs_da_format.h | 154 |
1 files changed, 128 insertions, 26 deletions
diff --git a/fs/xfs/libxfs/xfs_da_format.h b/fs/xfs/libxfs/xfs_da_format.h index 25e2841084e1..86de99e2f757 100644 --- a/fs/xfs/libxfs/xfs_da_format.h +++ b/fs/xfs/libxfs/xfs_da_format.h @@ -159,6 +159,17 @@ struct xfs_da3_intnode { #define XFS_DIR3_FT_MAX 9 +#define XFS_DIR3_FTYPE_STR \ + { XFS_DIR3_FT_UNKNOWN, "unknown" }, \ + { XFS_DIR3_FT_REG_FILE, "file" }, \ + { XFS_DIR3_FT_DIR, "directory" }, \ + { XFS_DIR3_FT_CHRDEV, "char" }, \ + { XFS_DIR3_FT_BLKDEV, "block" }, \ + { XFS_DIR3_FT_FIFO, "fifo" }, \ + { XFS_DIR3_FT_SOCK, "sock" }, \ + { XFS_DIR3_FT_SYMLINK, "symlink" }, \ + { XFS_DIR3_FT_WHT, "whiteout" } + /* * Byte offset in data block and shortform entry. */ @@ -578,20 +589,25 @@ xfs_dir2_block_leaf_p(struct xfs_dir2_block_tail *btp) #define XFS_ATTR_LEAF_MAPSIZE 3 /* how many freespace slots */ /* - * Entries are packed toward the top as tight as possible. - */ -struct xfs_attr_shortform { - struct xfs_attr_sf_hdr { /* constant-structure header block */ - __be16 totsize; /* total bytes in shortform list */ - __u8 count; /* count of active entries */ - __u8 padding; - } hdr; - struct xfs_attr_sf_entry { - uint8_t namelen; /* actual length of name (no NULL) */ - uint8_t valuelen; /* actual length of value (no NULL) */ - uint8_t flags; /* flags bits (see xfs_attr_leaf.h) */ - uint8_t nameval[]; /* name & value bytes concatenated */ - } list[1]; /* variable sized array */ + * Attribute storage when stored inside the inode. + * + * Small attribute lists are packed as tightly as possible so as to fit into the + * literal area of the inode. + * + * These "shortform" attribute forks consist of a single xfs_attr_sf_hdr header + * followed by zero or more xfs_attr_sf_entry structures. + */ +struct xfs_attr_sf_hdr { /* constant-structure header block */ + __be16 totsize; /* total bytes in shortform list */ + __u8 count; /* count of active entries */ + __u8 padding; +}; + +struct xfs_attr_sf_entry { + __u8 namelen; /* actual length of name (no NULL) */ + __u8 valuelen; /* actual length of value (no NULL) */ + __u8 flags; /* flags bits (XFS_ATTR_*) */ + __u8 nameval[]; /* name & value bytes concatenated */ }; typedef struct xfs_attr_leaf_map { /* RLE map of free bytes */ @@ -620,19 +636,29 @@ typedef struct xfs_attr_leaf_entry { /* sorted on key, not name */ 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 */ + /* + * In Linux 6.5 this flex array was converted from nameval[1] to + * nameval[]. Be very careful here about extra padding at the end; + * see xfs_attr_leaf_entsize_local() for details. + */ + __u8 nameval[]; /* 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 */ + /* + * In Linux 6.5 this flex array was converted from name[1] to name[]. + * Be very careful here about extra padding at the end; see + * xfs_attr_leaf_entsize_remote() for details. + */ + __u8 name[]; /* 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_entry_t entries[]; /* sorted on key, not name */ /* * The rest of the block contains the following structures after the * leaf entries, growing from the bottom up. The variables are never @@ -664,7 +690,7 @@ struct xfs_attr3_leaf_hdr { struct xfs_attr3_leafblock { struct xfs_attr3_leaf_hdr hdr; - struct xfs_attr_leaf_entry entries[1]; + struct xfs_attr_leaf_entry entries[]; /* * The rest of the block contains the following structures after the @@ -688,12 +714,30 @@ struct xfs_attr3_leafblock { #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_PARENT_BIT 3 /* parent pointer attrs */ #define XFS_ATTR_INCOMPLETE_BIT 7 /* attr in middle of create/delete */ #define XFS_ATTR_LOCAL (1u << XFS_ATTR_LOCAL_BIT) #define XFS_ATTR_ROOT (1u << XFS_ATTR_ROOT_BIT) #define XFS_ATTR_SECURE (1u << XFS_ATTR_SECURE_BIT) +#define XFS_ATTR_PARENT (1u << XFS_ATTR_PARENT_BIT) #define XFS_ATTR_INCOMPLETE (1u << XFS_ATTR_INCOMPLETE_BIT) -#define XFS_ATTR_NSP_ONDISK_MASK (XFS_ATTR_ROOT | XFS_ATTR_SECURE) + +#define XFS_ATTR_NSP_ONDISK_MASK (XFS_ATTR_ROOT | \ + XFS_ATTR_SECURE | \ + XFS_ATTR_PARENT) + +/* Private attr namespaces not exposed to userspace */ +#define XFS_ATTR_PRIVATE_NSP_MASK (XFS_ATTR_PARENT) + +#define XFS_ATTR_ONDISK_MASK (XFS_ATTR_NSP_ONDISK_MASK | \ + XFS_ATTR_LOCAL | \ + XFS_ATTR_INCOMPLETE) + +#define XFS_ATTR_NAMESPACE_STR \ + { XFS_ATTR_LOCAL, "local" }, \ + { XFS_ATTR_ROOT, "root" }, \ + { XFS_ATTR_SECURE, "secure" }, \ + { XFS_ATTR_PARENT, "parent" } /* * Alignment for namelist and valuelist entries (since they are mixed @@ -747,14 +791,61 @@ xfs_attr3_leaf_name_local(xfs_attr_leafblock_t *leafp, int idx) */ static inline int xfs_attr_leaf_entsize_remote(int nlen) { - return round_up(sizeof(struct xfs_attr_leaf_name_remote) - 1 + - nlen, XFS_ATTR_LEAF_NAME_ALIGN); + /* + * Prior to Linux 6.5, struct xfs_attr_leaf_name_remote ended with + * name[1], which was used as a flexarray. The layout of this struct + * is 9 bytes of fixed-length fields followed by a __u8 flex array at + * offset 9. + * + * On most architectures, struct xfs_attr_leaf_name_remote had two + * bytes of implicit padding at the end of the struct to make the + * struct length 12. After converting name[1] to name[], there are + * three implicit padding bytes and the struct size remains 12. + * However, there are compiler configurations that do not add implicit + * padding at all (m68k) and have been broken for years. + * + * This entsize computation historically added (the xattr name length) + * to (the padded struct length - 1) and rounded that sum up to the + * nearest multiple of 4 (NAME_ALIGN). IOWs, round_up(11 + nlen, 4). + * This is encoded in the ondisk format, so we cannot change this. + * + * Compute the entsize from offsetof of the flexarray and manually + * adding bytes for the implicit padding. + */ + const size_t remotesize = + offsetof(struct xfs_attr_leaf_name_remote, name) + 2; + + return round_up(remotesize + nlen, XFS_ATTR_LEAF_NAME_ALIGN); } static inline int xfs_attr_leaf_entsize_local(int nlen, int vlen) { - return round_up(sizeof(struct xfs_attr_leaf_name_local) - 1 + - nlen + vlen, XFS_ATTR_LEAF_NAME_ALIGN); + /* + * Prior to Linux 6.5, struct xfs_attr_leaf_name_local ended with + * nameval[1], which was used as a flexarray. The layout of this + * struct is 3 bytes of fixed-length fields followed by a __u8 flex + * array at offset 3. + * + * struct xfs_attr_leaf_name_local had zero bytes of implicit padding + * at the end of the struct to make the struct length 4. On most + * architectures, after converting nameval[1] to nameval[], there is + * one implicit padding byte and the struct size remains 4. However, + * there are compiler configurations that do not add implicit padding + * at all (m68k) and would break. + * + * This entsize computation historically added (the xattr name and + * value length) to (the padded struct length - 1) and rounded that sum + * up to the nearest multiple of 4 (NAME_ALIGN). IOWs, the formula is + * round_up(3 + nlen + vlen, 4). This is encoded in the ondisk format, + * so we cannot change this. + * + * Compute the entsize from offsetof of the flexarray and manually + * adding bytes for the implicit padding. + */ + const size_t localsize = + offsetof(struct xfs_attr_leaf_name_local, nameval); + + return round_up(localsize + nlen + vlen, XFS_ATTR_LEAF_NAME_ALIGN); } static inline int xfs_attr_leaf_entsize_local_max(int bsize) @@ -789,9 +880,7 @@ struct xfs_attr3_rmt_hdr { #define XFS_ATTR3_RMT_CRC_OFF offsetof(struct xfs_attr3_rmt_hdr, rm_crc) -#define XFS_ATTR3_RMT_BUF_SPACE(mp, bufsize) \ - ((bufsize) - (xfs_has_crc((mp)) ? \ - sizeof(struct xfs_attr3_rmt_hdr) : 0)) +unsigned int xfs_attr3_rmt_buf_space(struct xfs_mount *mp); /* Number of bytes in a directory block. */ static inline unsigned int xfs_dir2_dirblock_bytes(struct xfs_sb *sbp) @@ -802,4 +891,17 @@ static inline unsigned int xfs_dir2_dirblock_bytes(struct xfs_sb *sbp) xfs_failaddr_t xfs_da3_blkinfo_verify(struct xfs_buf *bp, struct xfs_da3_blkinfo *hdr3); +/* + * Parent pointer attribute format definition + * + * The xattr name contains the dirent name. + * The xattr value encodes the parent inode number and generation to ease + * opening parents by handle. + * The xattr hashval is xfs_dir2_namehash() ^ p_ino + */ +struct xfs_parent_rec { + __be64 p_ino; + __be32 p_gen; +} __packed; + #endif /* __XFS_DA_FORMAT_H__ */ |