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Diffstat (limited to 'fs/xfs/libxfs/xfs_da_btree.h')
| -rw-r--r-- | fs/xfs/libxfs/xfs_da_btree.h | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/fs/xfs/libxfs/xfs_da_btree.h b/fs/xfs/libxfs/xfs_da_btree.h new file mode 100644 index 000000000000..6e153e399a77 --- /dev/null +++ b/fs/xfs/libxfs/xfs_da_btree.h @@ -0,0 +1,221 @@ +/* + * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc. + * Copyright (c) 2013 Red Hat, Inc. + * All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ +#ifndef __XFS_DA_BTREE_H__ +#define __XFS_DA_BTREE_H__ + +struct xfs_bmap_free; +struct xfs_inode; +struct xfs_trans; +struct zone; +struct xfs_dir_ops; + +/* + * Directory/attribute geometry information. There will be one of these for each + * data fork type, and it will be passed around via the xfs_da_args. Global + * structures will be attached to the xfs_mount. + */ +struct xfs_da_geometry { + int blksize; /* da block size in bytes */ + int fsbcount; /* da block size in filesystem blocks */ + uint8_t fsblog; /* log2 of _filesystem_ block size */ + uint8_t blklog; /* log2 of da block size */ + uint node_ents; /* # of entries in a danode */ + int magicpct; /* 37% of block size in bytes */ + xfs_dablk_t datablk; /* blockno of dir data v2 */ + xfs_dablk_t leafblk; /* blockno of leaf data v2 */ + xfs_dablk_t freeblk; /* blockno of free data v2 */ +}; + +/*======================================================================== + * Btree searching and modification structure definitions. + *========================================================================*/ + +/* + * Search comparison results + */ +enum xfs_dacmp { + XFS_CMP_DIFFERENT, /* names are completely different */ + XFS_CMP_EXACT, /* names are exactly the same */ + XFS_CMP_CASE /* names are same but differ in case */ +}; + +/* + * Structure to ease passing around component names. + */ +typedef struct xfs_da_args { + struct xfs_da_geometry *geo; /* da block geometry */ + const __uint8_t *name; /* string (maybe not NULL terminated) */ + int namelen; /* length of string (maybe no NULL) */ + __uint8_t filetype; /* filetype of inode for directories */ + __uint8_t *value; /* set of bytes (maybe contain NULLs) */ + int valuelen; /* length of value */ + int flags; /* argument flags (eg: ATTR_NOCREATE) */ + xfs_dahash_t hashval; /* hash value of name */ + xfs_ino_t inumber; /* input/output inode number */ + struct xfs_inode *dp; /* directory inode to manipulate */ + xfs_fsblock_t *firstblock; /* ptr to firstblock for bmap calls */ + struct xfs_bmap_free *flist; /* ptr to freelist for bmap_finish */ + struct xfs_trans *trans; /* current trans (changes over time) */ + xfs_extlen_t total; /* total blocks needed, for 1st bmap */ + int whichfork; /* data or attribute fork */ + xfs_dablk_t blkno; /* blkno of attr leaf of interest */ + int index; /* index of attr of interest in blk */ + xfs_dablk_t rmtblkno; /* remote attr value starting blkno */ + int rmtblkcnt; /* remote attr value block count */ + int rmtvaluelen; /* remote attr value length in bytes */ + xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */ + int index2; /* index of 2nd attr in blk */ + xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */ + int rmtblkcnt2; /* remote attr value block count */ + int rmtvaluelen2; /* remote attr value length in bytes */ + int op_flags; /* operation flags */ + enum xfs_dacmp cmpresult; /* name compare result for lookups */ +} xfs_da_args_t; + +/* + * Operation flags: + */ +#define XFS_DA_OP_JUSTCHECK 0x0001 /* check for ok with no space */ +#define XFS_DA_OP_RENAME 0x0002 /* this is an atomic rename op */ +#define XFS_DA_OP_ADDNAME 0x0004 /* this is an add operation */ +#define XFS_DA_OP_OKNOENT 0x0008 /* lookup/add op, ENOENT ok, else die */ +#define XFS_DA_OP_CILOOKUP 0x0010 /* lookup to return CI name if found */ + +#define XFS_DA_OP_FLAGS \ + { XFS_DA_OP_JUSTCHECK, "JUSTCHECK" }, \ + { XFS_DA_OP_RENAME, "RENAME" }, \ + { XFS_DA_OP_ADDNAME, "ADDNAME" }, \ + { XFS_DA_OP_OKNOENT, "OKNOENT" }, \ + { XFS_DA_OP_CILOOKUP, "CILOOKUP" } + +/* + * Storage for holding state during Btree searches and split/join ops. + * + * Only need space for 5 intermediate nodes. With a minimum of 62-way + * fanout to the Btree, we can support over 900 million directory blocks, + * which is slightly more than enough. + */ +typedef struct xfs_da_state_blk { + struct xfs_buf *bp; /* buffer containing block */ + xfs_dablk_t blkno; /* filesystem blkno of buffer */ + xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */ + int index; /* relevant index into block */ + xfs_dahash_t hashval; /* last hash value in block */ + int magic; /* blk's magic number, ie: blk type */ +} xfs_da_state_blk_t; + +typedef struct xfs_da_state_path { + int active; /* number of active levels */ + xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH]; +} xfs_da_state_path_t; + +typedef struct xfs_da_state { + xfs_da_args_t *args; /* filename arguments */ + struct xfs_mount *mp; /* filesystem mount point */ + xfs_da_state_path_t path; /* search/split paths */ + xfs_da_state_path_t altpath; /* alternate path for join */ + unsigned char inleaf; /* insert into 1->lf, 0->splf */ + unsigned char extravalid; /* T/F: extrablk is in use */ + unsigned char extraafter; /* T/F: extrablk is after new */ + xfs_da_state_blk_t extrablk; /* for double-splits on leaves */ + /* for dirv2 extrablk is data */ +} xfs_da_state_t; + +/* + * Utility macros to aid in logging changed structure fields. + */ +#define XFS_DA_LOGOFF(BASE, ADDR) ((char *)(ADDR) - (char *)(BASE)) +#define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \ + (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \ + (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1) + +/* + * Name ops for directory and/or attr name operations + */ +struct xfs_nameops { + xfs_dahash_t (*hashname)(struct xfs_name *); + enum xfs_dacmp (*compname)(struct xfs_da_args *, + const unsigned char *, int); +}; + + +/*======================================================================== + * Function prototypes. + *========================================================================*/ + +/* + * Routines used for growing the Btree. + */ +int xfs_da3_node_create(struct xfs_da_args *args, xfs_dablk_t blkno, + int level, struct xfs_buf **bpp, int whichfork); +int xfs_da3_split(xfs_da_state_t *state); + +/* + * Routines used for shrinking the Btree. + */ +int xfs_da3_join(xfs_da_state_t *state); +void xfs_da3_fixhashpath(struct xfs_da_state *state, + struct xfs_da_state_path *path_to_to_fix); + +/* + * Routines used for finding things in the Btree. + */ +int xfs_da3_node_lookup_int(xfs_da_state_t *state, int *result); +int xfs_da3_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path, + int forward, int release, int *result); +/* + * Utility routines. + */ +int xfs_da3_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk, + xfs_da_state_blk_t *new_blk); +int xfs_da3_node_read(struct xfs_trans *tp, struct xfs_inode *dp, + xfs_dablk_t bno, xfs_daddr_t mappedbno, + struct xfs_buf **bpp, int which_fork); + +/* + * Utility routines. + */ +int xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno); +int xfs_da_grow_inode_int(struct xfs_da_args *args, xfs_fileoff_t *bno, + int count); +int xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp, + xfs_dablk_t bno, xfs_daddr_t mappedbno, + struct xfs_buf **bp, int whichfork); +int xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp, + xfs_dablk_t bno, xfs_daddr_t mappedbno, + struct xfs_buf **bpp, int whichfork, + const struct xfs_buf_ops *ops); +xfs_daddr_t xfs_da_reada_buf(struct xfs_inode *dp, xfs_dablk_t bno, + xfs_daddr_t mapped_bno, int whichfork, + const struct xfs_buf_ops *ops); +int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno, + struct xfs_buf *dead_buf); + +uint xfs_da_hashname(const __uint8_t *name_string, int name_length); +enum xfs_dacmp xfs_da_compname(struct xfs_da_args *args, + const unsigned char *name, int len); + + +xfs_da_state_t *xfs_da_state_alloc(void); +void xfs_da_state_free(xfs_da_state_t *state); + +extern struct kmem_zone *xfs_da_state_zone; +extern const struct xfs_nameops xfs_default_nameops; + +#endif /* __XFS_DA_BTREE_H__ */ |