diff options
Diffstat (limited to 'fs/xfs/xfs_dir2_sf.h')
| -rw-r--r-- | fs/xfs/xfs_dir2_sf.h | 47 |
1 files changed, 24 insertions, 23 deletions
diff --git a/fs/xfs/xfs_dir2_sf.h b/fs/xfs/xfs_dir2_sf.h index 208d2c3..c1ab2e7 100644 --- a/fs/xfs/xfs_dir2_sf.h +++ b/fs/xfs/xfs_dir2_sf.h @@ -21,8 +21,12 @@ /* * Directory layout when stored internal to an inode. * - * Small directories are packed as tightly as possible so as to - * fit into the literal area of the inode. + * Small directories are packed as tightly as possible so as to fit into the + * literal area of the inode. They consist of a single xfs_dir2_sf_hdr header + * followed by zero or more xfs_dir2_sf_entry structures. Due the different + * inode number storage size and the variable length name field in + * the xfs_dir2_sf_entry all these structure are variable length, and the + * accessors in this file should be used to iterate over them. */ struct uio; @@ -61,9 +65,9 @@ typedef struct { __uint8_t i[2]; } __arch_pack xfs_dir2_sf_off_t; * The parent directory has a dedicated field, and the self-pointer must * be calculated on the fly. * - * Entries are packed toward the top as tightly as possible. The header - * and the elements must be memcpy'd out into a work area to get correct - * alignment for the inode number fields. + * Entries are packed toward the top as tightly as possible, and thus may + * be misaligned. Care needs to be taken to access them through special + * helpers or copy them into aligned variables first. */ typedef struct xfs_dir2_sf_hdr { __uint8_t count; /* count of entries */ @@ -78,11 +82,6 @@ typedef struct xfs_dir2_sf_entry { xfs_dir2_inou_t inumber; /* inode number, var. offset */ } __arch_pack xfs_dir2_sf_entry_t; -typedef struct xfs_dir2_sf { - xfs_dir2_sf_hdr_t hdr; /* shortform header */ - xfs_dir2_sf_entry_t list[1]; /* shortform entries */ -} xfs_dir2_sf_t; - static inline int xfs_dir2_sf_hdr_size(int i8count) { return ((uint)sizeof(xfs_dir2_sf_hdr_t) - \ @@ -102,39 +101,41 @@ xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep, xfs_dir2_data_aoff_t off) INT_SET_UNALIGNED_16_BE(&(sfep)->offset.i, off); } -static inline int xfs_dir2_sf_entsize_byname(xfs_dir2_sf_t *sfp, int len) +static inline int xfs_dir2_sf_entsize_byname(xfs_dir2_sf_hdr_t *sfp, int len) { return ((uint)sizeof(xfs_dir2_sf_entry_t) - 1 + (len) - \ - ((sfp)->hdr.i8count == 0) * \ + ((sfp)->i8count == 0) * \ ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t))); } static inline int -xfs_dir2_sf_entsize_byentry(xfs_dir2_sf_t *sfp, xfs_dir2_sf_entry_t *sfep) +xfs_dir2_sf_entsize_byentry(xfs_dir2_sf_hdr_t *sfp, xfs_dir2_sf_entry_t *sfep) { return ((uint)sizeof(xfs_dir2_sf_entry_t) - 1 + (sfep)->namelen - \ - ((sfp)->hdr.i8count == 0) * \ + ((sfp)->i8count == 0) * \ ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t))); } -static inline xfs_dir2_sf_entry_t *xfs_dir2_sf_firstentry(xfs_dir2_sf_t *sfp) +static inline struct xfs_dir2_sf_entry * +xfs_dir2_sf_firstentry(struct xfs_dir2_sf_hdr *hdr) { - return ((xfs_dir2_sf_entry_t *) \ - ((char *)(sfp) + xfs_dir2_sf_hdr_size(sfp->hdr.i8count))); + return (struct xfs_dir2_sf_entry *) + ((char *)hdr + xfs_dir2_sf_hdr_size(hdr->i8count)); } -static inline xfs_dir2_sf_entry_t * -xfs_dir2_sf_nextentry(xfs_dir2_sf_t *sfp, xfs_dir2_sf_entry_t *sfep) +static inline struct xfs_dir2_sf_entry * +xfs_dir2_sf_nextentry(struct xfs_dir2_sf_hdr *hdr, + struct xfs_dir2_sf_entry *sfep) { - return ((xfs_dir2_sf_entry_t *) \ - ((char *)(sfep) + xfs_dir2_sf_entsize_byentry(sfp,sfep))); + return (struct xfs_dir2_sf_entry *) + ((char *)sfep + xfs_dir2_sf_entsize_byentry(hdr, sfep)); } /* * Functions. */ -extern xfs_ino_t xfs_dir2_sf_get_parent_ino(struct xfs_dir2_sf *sfp); -extern xfs_ino_t xfs_dir2_sfe_get_ino(struct xfs_dir2_sf *sfp, +extern xfs_ino_t xfs_dir2_sf_get_parent_ino(struct xfs_dir2_sf_hdr *sfp); +extern xfs_ino_t xfs_dir2_sfe_get_ino(struct xfs_dir2_sf_hdr *sfp, struct xfs_dir2_sf_entry *sfep); extern int xfs_dir2_block_sfsize(struct xfs_inode *dp, struct xfs_dir2_block *block, |