2 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
3 * Copyright (c) 2013 Red Hat, Inc.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation.
10 * This program is distributed in the hope that it would be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 #ifndef __XFS_DA_BTREE_H__
20 #define __XFS_DA_BTREE_H__
27 /*========================================================================
28 * Btree searching and modification structure definitions.
29 *========================================================================*/
32 * Search comparison results
35 XFS_CMP_DIFFERENT, /* names are completely different */
36 XFS_CMP_EXACT, /* names are exactly the same */
37 XFS_CMP_CASE /* names are same but differ in case */
41 * Structure to ease passing around component names.
43 typedef struct xfs_da_args {
44 const __uint8_t *name; /* string (maybe not NULL terminated) */
45 int namelen; /* length of string (maybe no NULL) */
46 __uint8_t filetype; /* filetype of inode for directories */
47 __uint8_t *value; /* set of bytes (maybe contain NULLs) */
48 int valuelen; /* length of value */
49 int flags; /* argument flags (eg: ATTR_NOCREATE) */
50 xfs_dahash_t hashval; /* hash value of name */
51 xfs_ino_t inumber; /* input/output inode number */
52 struct xfs_inode *dp; /* directory inode to manipulate */
53 xfs_fsblock_t *firstblock; /* ptr to firstblock for bmap calls */
54 struct xfs_bmap_free *flist; /* ptr to freelist for bmap_finish */
55 struct xfs_trans *trans; /* current trans (changes over time) */
56 xfs_extlen_t total; /* total blocks needed, for 1st bmap */
57 int whichfork; /* data or attribute fork */
58 xfs_dablk_t blkno; /* blkno of attr leaf of interest */
59 int index; /* index of attr of interest in blk */
60 xfs_dablk_t rmtblkno; /* remote attr value starting blkno */
61 int rmtblkcnt; /* remote attr value block count */
62 xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */
63 int index2; /* index of 2nd attr in blk */
64 xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */
65 int rmtblkcnt2; /* remote attr value block count */
66 int op_flags; /* operation flags */
67 enum xfs_dacmp cmpresult; /* name compare result for lookups */
73 #define XFS_DA_OP_JUSTCHECK 0x0001 /* check for ok with no space */
74 #define XFS_DA_OP_RENAME 0x0002 /* this is an atomic rename op */
75 #define XFS_DA_OP_ADDNAME 0x0004 /* this is an add operation */
76 #define XFS_DA_OP_OKNOENT 0x0008 /* lookup/add op, ENOENT ok, else die */
77 #define XFS_DA_OP_CILOOKUP 0x0010 /* lookup to return CI name if found */
79 #define XFS_DA_OP_FLAGS \
80 { XFS_DA_OP_JUSTCHECK, "JUSTCHECK" }, \
81 { XFS_DA_OP_RENAME, "RENAME" }, \
82 { XFS_DA_OP_ADDNAME, "ADDNAME" }, \
83 { XFS_DA_OP_OKNOENT, "OKNOENT" }, \
84 { XFS_DA_OP_CILOOKUP, "CILOOKUP" }
87 * Storage for holding state during Btree searches and split/join ops.
89 * Only need space for 5 intermediate nodes. With a minimum of 62-way
90 * fanout to the Btree, we can support over 900 million directory blocks,
91 * which is slightly more than enough.
93 typedef struct xfs_da_state_blk {
94 struct xfs_buf *bp; /* buffer containing block */
95 xfs_dablk_t blkno; /* filesystem blkno of buffer */
96 xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */
97 int index; /* relevant index into block */
98 xfs_dahash_t hashval; /* last hash value in block */
99 int magic; /* blk's magic number, ie: blk type */
100 } xfs_da_state_blk_t;
102 typedef struct xfs_da_state_path {
103 int active; /* number of active levels */
104 xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH];
105 } xfs_da_state_path_t;
107 typedef struct xfs_da_state {
108 xfs_da_args_t *args; /* filename arguments */
109 struct xfs_mount *mp; /* filesystem mount point */
110 unsigned int blocksize; /* logical block size */
111 unsigned int node_ents; /* how many entries in danode */
112 xfs_da_state_path_t path; /* search/split paths */
113 xfs_da_state_path_t altpath; /* alternate path for join */
114 unsigned char inleaf; /* insert into 1->lf, 0->splf */
115 unsigned char extravalid; /* T/F: extrablk is in use */
116 unsigned char extraafter; /* T/F: extrablk is after new */
117 xfs_da_state_blk_t extrablk; /* for double-splits on leaves */
118 /* for dirv2 extrablk is data */
122 * Utility macros to aid in logging changed structure fields.
124 #define XFS_DA_LOGOFF(BASE, ADDR) ((char *)(ADDR) - (char *)(BASE))
125 #define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \
126 (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \
127 (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1)
130 * Name ops for directory and/or attr name operations
133 xfs_dahash_t (*hashname)(struct xfs_name *);
134 enum xfs_dacmp (*compname)(struct xfs_da_args *,
135 const unsigned char *, int);
139 /*========================================================================
140 * Function prototypes.
141 *========================================================================*/
144 * Routines used for growing the Btree.
146 int xfs_da3_node_create(struct xfs_da_args *args, xfs_dablk_t blkno,
147 int level, struct xfs_buf **bpp, int whichfork);
148 int xfs_da3_split(xfs_da_state_t *state);
151 * Routines used for shrinking the Btree.
153 int xfs_da3_join(xfs_da_state_t *state);
154 void xfs_da3_fixhashpath(struct xfs_da_state *state,
155 struct xfs_da_state_path *path_to_to_fix);
158 * Routines used for finding things in the Btree.
160 int xfs_da3_node_lookup_int(xfs_da_state_t *state, int *result);
161 int xfs_da3_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path,
162 int forward, int release, int *result);
166 int xfs_da3_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk,
167 xfs_da_state_blk_t *new_blk);
168 int xfs_da3_node_read(struct xfs_trans *tp, struct xfs_inode *dp,
169 xfs_dablk_t bno, xfs_daddr_t mappedbno,
170 struct xfs_buf **bpp, int which_fork);
175 int xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno);
176 int xfs_da_grow_inode_int(struct xfs_da_args *args, xfs_fileoff_t *bno,
178 int xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp,
179 xfs_dablk_t bno, xfs_daddr_t mappedbno,
180 struct xfs_buf **bp, int whichfork);
181 int xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp,
182 xfs_dablk_t bno, xfs_daddr_t mappedbno,
183 struct xfs_buf **bpp, int whichfork,
184 const struct xfs_buf_ops *ops);
185 xfs_daddr_t xfs_da_reada_buf(struct xfs_trans *trans, struct xfs_inode *dp,
186 xfs_dablk_t bno, xfs_daddr_t mapped_bno,
187 int whichfork, const struct xfs_buf_ops *ops);
188 int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
189 struct xfs_buf *dead_buf);
191 uint xfs_da_hashname(const __uint8_t *name_string, int name_length);
192 enum xfs_dacmp xfs_da_compname(struct xfs_da_args *args,
193 const unsigned char *name, int len);
196 xfs_da_state_t *xfs_da_state_alloc(void);
197 void xfs_da_state_free(xfs_da_state_t *state);
199 extern struct kmem_zone *xfs_da_state_zone;
200 extern const struct xfs_nameops xfs_default_nameops;
202 #endif /* __XFS_DA_BTREE_H__ */