1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6 #ifndef __XFS_INODE_FORK_H__
7 #define __XFS_INODE_FORK_H__
8
9 struct xfs_inode_log_item;
10 struct xfs_dinode;
11
12 /*
13 * File incore extent information, present for each of data & attr forks.
14 */
15 struct xfs_ifork {
16 int64_t if_bytes; /* bytes in if_data */
17 struct xfs_btree_block *if_broot; /* file's incore btree root */
18 unsigned int if_seq; /* fork mod counter */
19 int if_height; /* height of the extent tree */
20 void *if_data; /* extent tree root or
21 inline data */
22 xfs_extnum_t if_nextents; /* # of extents in this fork */
23 short if_broot_bytes; /* bytes allocated for root */
24 int8_t if_format; /* format of this fork */
25 uint8_t if_needextents; /* extents have not been read */
26 };
27
28 /*
29 * Worst-case increase in the fork extent count when we're adding a single
30 * extent to a fork and there's no possibility of splitting an existing mapping.
31 */
32 #define XFS_IEXT_ADD_NOSPLIT_CNT (1)
33
34 /*
35 * Punching out an extent from the middle of an existing extent can cause the
36 * extent count to increase by 1.
37 * i.e. | Old extent | Hole | Old extent |
38 */
39 #define XFS_IEXT_PUNCH_HOLE_CNT (1)
40
41 /*
42 * Adding/removing an xattr can cause XFS_DA_NODE_MAXDEPTH extents to
43 * be added. One extra extent for dabtree in case a local attr is
44 * large enough to cause a double split. It can also cause extent
45 * count to increase proportional to the size of a remote xattr's
46 * value.
47 */
48 #define XFS_IEXT_ATTR_MANIP_CNT(rmt_blks) \
49 (XFS_DA_NODE_MAXDEPTH + max(1, rmt_blks))
50
51 /*
52 * A write to a sub-interval of an existing unwritten extent causes the original
53 * extent to be split into 3 extents
54 * i.e. | Unwritten | Real | Unwritten |
55 * Hence extent count can increase by 2.
56 */
57 #define XFS_IEXT_WRITE_UNWRITTEN_CNT (2)
58
59
60 /*
61 * Moving an extent to data fork can cause a sub-interval of an existing extent
62 * to be unmapped. This will increase extent count by 1. Mapping in the new
63 * extent can increase the extent count by 1 again i.e.
64 * | Old extent | New extent | Old extent |
65 * Hence number of extents increases by 2.
66 */
67 #define XFS_IEXT_REFLINK_END_COW_CNT (2)
68
69 /*
70 * Removing an initial range of source/donor file's extent and adding a new
71 * extent (from donor/source file) in its place will cause extent count to
72 * increase by 1.
73 */
74 #define XFS_IEXT_SWAP_RMAP_CNT (1)
75
76 /*
77 * Fork handling.
78 */
79 #define XFS_IFORK_MAXEXT(ip, w) \
80 (xfs_inode_fork_size(ip, w) / sizeof(xfs_bmbt_rec_t))
81
82 static inline bool xfs_ifork_has_extents(struct xfs_ifork *ifp)
83 {
84 return ifp->if_format == XFS_DINODE_FMT_EXTENTS ||
85 ifp->if_format == XFS_DINODE_FMT_BTREE;
86 }
87
88 static inline xfs_extnum_t xfs_ifork_nextents(struct xfs_ifork *ifp)
89 {
90 if (!ifp)
91 return 0;
92 return ifp->if_nextents;
93 }
94
95 static inline int8_t xfs_ifork_format(struct xfs_ifork *ifp)
96 {
97 if (!ifp)
98 return XFS_DINODE_FMT_EXTENTS;
99 return ifp->if_format;
100 }
101
102 static inline xfs_extnum_t xfs_iext_max_nextents(bool has_large_extent_counts,
103 int whichfork)
104 {
105 switch (whichfork) {
106 case XFS_DATA_FORK:
107 case XFS_COW_FORK:
108 if (has_large_extent_counts)
109 return XFS_MAX_EXTCNT_DATA_FORK_LARGE;
110 return XFS_MAX_EXTCNT_DATA_FORK_SMALL;
111
112 case XFS_ATTR_FORK:
113 if (has_large_extent_counts)
114 return XFS_MAX_EXTCNT_ATTR_FORK_LARGE;
115 return XFS_MAX_EXTCNT_ATTR_FORK_SMALL;
116
117 default:
118 ASSERT(0);
119 return 0;
120 }
121 }
122
123 static inline xfs_extnum_t
124 xfs_dfork_data_extents(
125 struct xfs_dinode *dip)
126 {
127 if (xfs_dinode_has_large_extent_counts(dip))
128 return be64_to_cpu(dip->di_big_nextents);
129
130 return be32_to_cpu(dip->di_nextents);
131 }
132
133 static inline xfs_extnum_t
134 xfs_dfork_attr_extents(
135 struct xfs_dinode *dip)
136 {
137 if (xfs_dinode_has_large_extent_counts(dip))
138 return be32_to_cpu(dip->di_big_anextents);
139
140 return be16_to_cpu(dip->di_anextents);
141 }
142
143 static inline xfs_extnum_t
144 xfs_dfork_nextents(
145 struct xfs_dinode *dip,
146 int whichfork)
147 {
148 switch (whichfork) {
149 case XFS_DATA_FORK:
150 return xfs_dfork_data_extents(dip);
151 case XFS_ATTR_FORK:
152 return xfs_dfork_attr_extents(dip);
153 default:
154 ASSERT(0);
155 break;
156 }
157
158 return 0;
159 }
160
161 void xfs_ifork_zap_attr(struct xfs_inode *ip);
162 void xfs_ifork_init_attr(struct xfs_inode *ip, enum xfs_dinode_fmt format,
163 xfs_extnum_t nextents);
164 struct xfs_ifork *xfs_iext_state_to_fork(struct xfs_inode *ip, int state);
165
166 int xfs_iformat_data_fork(struct xfs_inode *, struct xfs_dinode *);
167 int xfs_iformat_attr_fork(struct xfs_inode *, struct xfs_dinode *);
168 void xfs_iflush_fork(struct xfs_inode *, struct xfs_dinode *,
169 struct xfs_inode_log_item *, int);
170 void xfs_idestroy_fork(struct xfs_ifork *ifp);
171 void * xfs_idata_realloc(struct xfs_inode *ip, int64_t byte_diff,
172 int whichfork);
173 void xfs_iroot_realloc(struct xfs_inode *, int, int);
174 int xfs_iread_extents(struct xfs_trans *, struct xfs_inode *, int);
175 int xfs_iextents_copy(struct xfs_inode *, struct xfs_bmbt_rec *,
176 int);
177 void xfs_init_local_fork(struct xfs_inode *ip, int whichfork,
178 const void *data, int64_t size);
179
180 xfs_extnum_t xfs_iext_count(struct xfs_ifork *ifp);
181 void xfs_iext_insert_raw(struct xfs_ifork *ifp,
182 struct xfs_iext_cursor *cur,
183 struct xfs_bmbt_irec *irec);
184 void xfs_iext_insert(struct xfs_inode *, struct xfs_iext_cursor *cur,
185 struct xfs_bmbt_irec *, int);
186 void xfs_iext_remove(struct xfs_inode *, struct xfs_iext_cursor *,
187 int);
188 void xfs_iext_destroy(struct xfs_ifork *);
189
190 bool xfs_iext_lookup_extent(struct xfs_inode *ip,
191 struct xfs_ifork *ifp, xfs_fileoff_t bno,
192 struct xfs_iext_cursor *cur,
193 struct xfs_bmbt_irec *gotp);
194 bool xfs_iext_lookup_extent_before(struct xfs_inode *ip,
195 struct xfs_ifork *ifp, xfs_fileoff_t *end,
196 struct xfs_iext_cursor *cur,
197 struct xfs_bmbt_irec *gotp);
198 bool xfs_iext_get_extent(struct xfs_ifork *ifp,
199 struct xfs_iext_cursor *cur,
200 struct xfs_bmbt_irec *gotp);
201 void xfs_iext_update_extent(struct xfs_inode *ip, int state,
202 struct xfs_iext_cursor *cur,
203 struct xfs_bmbt_irec *gotp);
204
205 void xfs_iext_first(struct xfs_ifork *, struct xfs_iext_cursor *);
206 void xfs_iext_last(struct xfs_ifork *, struct xfs_iext_cursor *);
207 void xfs_iext_next(struct xfs_ifork *, struct xfs_iext_cursor *);
208 void xfs_iext_prev(struct xfs_ifork *, struct xfs_iext_cursor *);
209
210 static inline bool xfs_iext_next_extent(struct xfs_ifork *ifp,
211 struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
212 {
213 xfs_iext_next(ifp, cur);
214 return xfs_iext_get_extent(ifp, cur, gotp);
215 }
216
217 static inline bool xfs_iext_prev_extent(struct xfs_ifork *ifp,
218 struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
219 {
220 xfs_iext_prev(ifp, cur);
221 return xfs_iext_get_extent(ifp, cur, gotp);
222 }
223
224 /*
225 * Return the extent after cur in gotp without updating the cursor.
226 */
227 static inline bool xfs_iext_peek_next_extent(struct xfs_ifork *ifp,
228 struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
229 {
230 struct xfs_iext_cursor ncur = *cur;
231
232 xfs_iext_next(ifp, &ncur);
233 return xfs_iext_get_extent(ifp, &ncur, gotp);
234 }
235
236 /*
237 * Return the extent before cur in gotp without updating the cursor.
238 */
239 static inline bool xfs_iext_peek_prev_extent(struct xfs_ifork *ifp,
240 struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
241 {
242 struct xfs_iext_cursor ncur = *cur;
243
244 xfs_iext_prev(ifp, &ncur);
245 return xfs_iext_get_extent(ifp, &ncur, gotp);
246 }
247
248 #define for_each_xfs_iext(ifp, ext, got) \
249 for (xfs_iext_first((ifp), (ext)); \
250 xfs_iext_get_extent((ifp), (ext), (got)); \
251 xfs_iext_next((ifp), (ext)))
252
253 extern struct kmem_cache *xfs_ifork_cache;
254
255 extern void xfs_ifork_init_cow(struct xfs_inode *ip);
256
257 int xfs_ifork_verify_local_data(struct xfs_inode *ip);
258 int xfs_ifork_verify_local_attr(struct xfs_inode *ip);
259 int xfs_iext_count_extend(struct xfs_trans *tp, struct xfs_inode *ip,
260 int whichfork, uint nr_to_add);
261 bool xfs_ifork_is_realtime(struct xfs_inode *ip, int whichfork);
262
263 /* returns true if the fork has extents but they are not read in yet. */
264 static inline bool xfs_need_iread_extents(const struct xfs_ifork *ifp)
265 {
266 /* see xfs_iformat_{data,attr}_fork() for needextents semantics */
267 return smp_load_acquire(&ifp->if_needextents) != 0;
268 }
269
270 #endif /* __XFS_INODE_FORK_H__ */
271
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.