xref: /openbmc/linux/fs/xfs/libxfs/xfs_bmap.h (revision 9aa2cba7)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
4  * All Rights Reserved.
5  */
6 #ifndef __XFS_BMAP_H__
7 #define	__XFS_BMAP_H__
8 
9 struct getbmap;
10 struct xfs_bmbt_irec;
11 struct xfs_ifork;
12 struct xfs_inode;
13 struct xfs_mount;
14 struct xfs_trans;
15 struct xfs_alloc_arg;
16 
17 /*
18  * Argument structure for xfs_bmap_alloc.
19  */
20 struct xfs_bmalloca {
21 	struct xfs_trans	*tp;	/* transaction pointer */
22 	struct xfs_inode	*ip;	/* incore inode pointer */
23 	struct xfs_bmbt_irec	prev;	/* extent before the new one */
24 	struct xfs_bmbt_irec	got;	/* extent after, or delayed */
25 
26 	xfs_fileoff_t		offset;	/* offset in file filling in */
27 	xfs_extlen_t		length;	/* i/o length asked/allocated */
28 	xfs_fsblock_t		blkno;	/* starting block of new extent */
29 
30 	struct xfs_btree_cur	*cur;	/* btree cursor */
31 	struct xfs_iext_cursor	icur;	/* incore extent cursor */
32 	int			nallocs;/* number of extents alloc'd */
33 	int			logflags;/* flags for transaction logging */
34 
35 	xfs_extlen_t		total;	/* total blocks needed for xaction */
36 	xfs_extlen_t		minlen;	/* minimum allocation size (blocks) */
37 	xfs_extlen_t		minleft; /* amount must be left after alloc */
38 	bool			eof;	/* set if allocating past last extent */
39 	bool			wasdel;	/* replacing a delayed allocation */
40 	bool			aeof;	/* allocated space at eof */
41 	bool			conv;	/* overwriting unwritten extents */
42 	int			datatype;/* data type being allocated */
43 	uint32_t		flags;
44 };
45 
46 #define	XFS_BMAP_MAX_NMAP	4
47 
48 /*
49  * Flags for xfs_bmapi_*
50  */
51 #define XFS_BMAPI_ENTIRE	(1u << 0) /* return entire extent untrimmed */
52 #define XFS_BMAPI_METADATA	(1u << 1) /* mapping metadata not user data */
53 #define XFS_BMAPI_ATTRFORK	(1u << 2) /* use attribute fork not data */
54 #define XFS_BMAPI_PREALLOC	(1u << 3) /* preallocating unwritten space */
55 #define XFS_BMAPI_CONTIG	(1u << 4) /* must allocate only one extent */
56 /*
57  * unwritten extent conversion - this needs write cache flushing and no additional
58  * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
59  * from written to unwritten, otherwise convert from unwritten to written.
60  */
61 #define XFS_BMAPI_CONVERT	(1u << 5)
62 
63 /*
64  * allocate zeroed extents - this requires all newly allocated user data extents
65  * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
66  * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
67  * during the allocation range to zeroed written extents.
68  */
69 #define XFS_BMAPI_ZERO		(1u << 6)
70 
71 /*
72  * Map the inode offset to the block given in ap->firstblock.  Primarily
73  * used for reflink.  The range must be in a hole, and this flag cannot be
74  * turned on with PREALLOC or CONVERT, and cannot be used on the attr fork.
75  *
76  * For bunmapi, this flag unmaps the range without adjusting quota, reducing
77  * refcount, or freeing the blocks.
78  */
79 #define XFS_BMAPI_REMAP		(1u << 7)
80 
81 /* Map something in the CoW fork. */
82 #define XFS_BMAPI_COWFORK	(1u << 8)
83 
84 /* Skip online discard of freed extents */
85 #define XFS_BMAPI_NODISCARD	(1u << 9)
86 
87 /* Do not update the rmap btree.  Used for reconstructing bmbt from rmapbt. */
88 #define XFS_BMAPI_NORMAP	(1u << 10)
89 
90 #define XFS_BMAPI_FLAGS \
91 	{ XFS_BMAPI_ENTIRE,	"ENTIRE" }, \
92 	{ XFS_BMAPI_METADATA,	"METADATA" }, \
93 	{ XFS_BMAPI_ATTRFORK,	"ATTRFORK" }, \
94 	{ XFS_BMAPI_PREALLOC,	"PREALLOC" }, \
95 	{ XFS_BMAPI_CONTIG,	"CONTIG" }, \
96 	{ XFS_BMAPI_CONVERT,	"CONVERT" }, \
97 	{ XFS_BMAPI_ZERO,	"ZERO" }, \
98 	{ XFS_BMAPI_REMAP,	"REMAP" }, \
99 	{ XFS_BMAPI_COWFORK,	"COWFORK" }, \
100 	{ XFS_BMAPI_NODISCARD,	"NODISCARD" }, \
101 	{ XFS_BMAPI_NORMAP,	"NORMAP" }
102 
103 
104 static inline int xfs_bmapi_aflag(int w)
105 {
106 	return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK :
107 	       (w == XFS_COW_FORK ? XFS_BMAPI_COWFORK : 0));
108 }
109 
110 static inline int xfs_bmapi_whichfork(uint32_t bmapi_flags)
111 {
112 	if (bmapi_flags & XFS_BMAPI_COWFORK)
113 		return XFS_COW_FORK;
114 	else if (bmapi_flags & XFS_BMAPI_ATTRFORK)
115 		return XFS_ATTR_FORK;
116 	return XFS_DATA_FORK;
117 }
118 
119 /*
120  * Special values for xfs_bmbt_irec_t br_startblock field.
121  */
122 #define	DELAYSTARTBLOCK		((xfs_fsblock_t)-1LL)
123 #define	HOLESTARTBLOCK		((xfs_fsblock_t)-2LL)
124 
125 /*
126  * Flags for xfs_bmap_add_extent*.
127  */
128 #define BMAP_LEFT_CONTIG	(1u << 0)
129 #define BMAP_RIGHT_CONTIG	(1u << 1)
130 #define BMAP_LEFT_FILLING	(1u << 2)
131 #define BMAP_RIGHT_FILLING	(1u << 3)
132 #define BMAP_LEFT_DELAY		(1u << 4)
133 #define BMAP_RIGHT_DELAY	(1u << 5)
134 #define BMAP_LEFT_VALID		(1u << 6)
135 #define BMAP_RIGHT_VALID	(1u << 7)
136 #define BMAP_ATTRFORK		(1u << 8)
137 #define BMAP_COWFORK		(1u << 9)
138 
139 #define XFS_BMAP_EXT_FLAGS \
140 	{ BMAP_LEFT_CONTIG,	"LC" }, \
141 	{ BMAP_RIGHT_CONTIG,	"RC" }, \
142 	{ BMAP_LEFT_FILLING,	"LF" }, \
143 	{ BMAP_RIGHT_FILLING,	"RF" }, \
144 	{ BMAP_ATTRFORK,	"ATTR" }, \
145 	{ BMAP_COWFORK,		"COW" }
146 
147 /* Return true if the extent is an allocated extent, written or not. */
148 static inline bool xfs_bmap_is_real_extent(const struct xfs_bmbt_irec *irec)
149 {
150 	return irec->br_startblock != HOLESTARTBLOCK &&
151 		irec->br_startblock != DELAYSTARTBLOCK &&
152 		!isnullstartblock(irec->br_startblock);
153 }
154 
155 /*
156  * Return true if the extent is a real, allocated extent, or false if it is  a
157  * delayed allocation, and unwritten extent or a hole.
158  */
159 static inline bool xfs_bmap_is_written_extent(struct xfs_bmbt_irec *irec)
160 {
161 	return xfs_bmap_is_real_extent(irec) &&
162 	       irec->br_state != XFS_EXT_UNWRITTEN;
163 }
164 
165 /*
166  * Check the mapping for obviously garbage allocations that could trash the
167  * filesystem immediately.
168  */
169 #define xfs_valid_startblock(ip, startblock) \
170 	((startblock) != 0 || XFS_IS_REALTIME_INODE(ip))
171 
172 int	xfs_bmap_longest_free_extent(struct xfs_perag *pag,
173 		struct xfs_trans *tp, xfs_extlen_t *blen);
174 void	xfs_trim_extent(struct xfs_bmbt_irec *irec, xfs_fileoff_t bno,
175 		xfs_filblks_t len);
176 unsigned int xfs_bmap_compute_attr_offset(struct xfs_mount *mp);
177 int	xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
178 void	xfs_bmap_local_to_extents_empty(struct xfs_trans *tp,
179 		struct xfs_inode *ip, int whichfork);
180 void	xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
181 int	xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
182 		xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
183 int	xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
184 		xfs_fileoff_t *last_block, int whichfork);
185 int	xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
186 		int whichfork);
187 int	xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
188 		xfs_filblks_t len, struct xfs_bmbt_irec *mval,
189 		int *nmap, uint32_t flags);
190 int	xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
191 		xfs_fileoff_t bno, xfs_filblks_t len, uint32_t flags,
192 		xfs_extlen_t total, struct xfs_bmbt_irec *mval, int *nmap);
193 int	__xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
194 		xfs_fileoff_t bno, xfs_filblks_t *rlen, uint32_t flags,
195 		xfs_extnum_t nexts);
196 int	xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
197 		xfs_fileoff_t bno, xfs_filblks_t len, uint32_t flags,
198 		xfs_extnum_t nexts, int *done);
199 int	xfs_bmap_del_extent_delay(struct xfs_inode *ip, int whichfork,
200 		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
201 		struct xfs_bmbt_irec *del);
202 void	xfs_bmap_del_extent_cow(struct xfs_inode *ip,
203 		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
204 		struct xfs_bmbt_irec *del);
205 uint	xfs_default_attroffset(struct xfs_inode *ip);
206 int	xfs_bmap_collapse_extents(struct xfs_trans *tp, struct xfs_inode *ip,
207 		xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
208 		bool *done);
209 int	xfs_bmap_can_insert_extents(struct xfs_inode *ip, xfs_fileoff_t off,
210 		xfs_fileoff_t shift);
211 int	xfs_bmap_insert_extents(struct xfs_trans *tp, struct xfs_inode *ip,
212 		xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
213 		bool *done, xfs_fileoff_t stop_fsb);
214 int	xfs_bmap_split_extent(struct xfs_trans *tp, struct xfs_inode *ip,
215 		xfs_fileoff_t split_offset);
216 int	xfs_bmapi_reserve_delalloc(struct xfs_inode *ip, int whichfork,
217 		xfs_fileoff_t off, xfs_filblks_t len, xfs_filblks_t prealloc,
218 		struct xfs_bmbt_irec *got, struct xfs_iext_cursor *cur,
219 		int eof);
220 int	xfs_bmapi_convert_delalloc(struct xfs_inode *ip, int whichfork,
221 		xfs_off_t offset, struct iomap *iomap, unsigned int *seq);
222 int	xfs_bmap_add_extent_unwritten_real(struct xfs_trans *tp,
223 		struct xfs_inode *ip, int whichfork,
224 		struct xfs_iext_cursor *icur, struct xfs_btree_cur **curp,
225 		struct xfs_bmbt_irec *new, int *logflagsp);
226 xfs_extlen_t xfs_bmapi_minleft(struct xfs_trans *tp, struct xfs_inode *ip,
227 		int fork);
228 int	xfs_bmap_btalloc_low_space(struct xfs_bmalloca *ap,
229 		struct xfs_alloc_arg *args);
230 
231 enum xfs_bmap_intent_type {
232 	XFS_BMAP_MAP = 1,
233 	XFS_BMAP_UNMAP,
234 };
235 
236 struct xfs_bmap_intent {
237 	struct list_head			bi_list;
238 	enum xfs_bmap_intent_type		bi_type;
239 	int					bi_whichfork;
240 	struct xfs_inode			*bi_owner;
241 	struct xfs_perag			*bi_pag;
242 	struct xfs_bmbt_irec			bi_bmap;
243 };
244 
245 void xfs_bmap_update_get_group(struct xfs_mount *mp,
246 		struct xfs_bmap_intent *bi);
247 
248 int	xfs_bmap_finish_one(struct xfs_trans *tp, struct xfs_bmap_intent *bi);
249 void	xfs_bmap_map_extent(struct xfs_trans *tp, struct xfs_inode *ip,
250 		struct xfs_bmbt_irec *imap);
251 void	xfs_bmap_unmap_extent(struct xfs_trans *tp, struct xfs_inode *ip,
252 		struct xfs_bmbt_irec *imap);
253 
254 static inline uint32_t xfs_bmap_fork_to_state(int whichfork)
255 {
256 	switch (whichfork) {
257 	case XFS_ATTR_FORK:
258 		return BMAP_ATTRFORK;
259 	case XFS_COW_FORK:
260 		return BMAP_COWFORK;
261 	default:
262 		return 0;
263 	}
264 }
265 
266 xfs_failaddr_t xfs_bmap_validate_extent(struct xfs_inode *ip, int whichfork,
267 		struct xfs_bmbt_irec *irec);
268 int xfs_bmap_complain_bad_rec(struct xfs_inode *ip, int whichfork,
269 		xfs_failaddr_t fa, const struct xfs_bmbt_irec *irec);
270 
271 int	xfs_bmapi_remap(struct xfs_trans *tp, struct xfs_inode *ip,
272 		xfs_fileoff_t bno, xfs_filblks_t len, xfs_fsblock_t startblock,
273 		uint32_t flags);
274 
275 extern struct kmem_cache	*xfs_bmap_intent_cache;
276 
277 int __init xfs_bmap_intent_init_cache(void);
278 void xfs_bmap_intent_destroy_cache(void);
279 
280 #endif	/* __XFS_BMAP_H__ */
281