xref: /openbmc/linux/fs/xfs/libxfs/xfs_bmap.h (revision 48cc39c3)
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 
16 extern kmem_zone_t	*xfs_bmap_free_item_zone;
17 
18 /*
19  * Argument structure for xfs_bmap_alloc.
20  */
21 struct xfs_bmalloca {
22 	struct xfs_trans	*tp;	/* transaction pointer */
23 	struct xfs_inode	*ip;	/* incore inode pointer */
24 	struct xfs_bmbt_irec	prev;	/* extent before the new one */
25 	struct xfs_bmbt_irec	got;	/* extent after, or delayed */
26 
27 	xfs_fileoff_t		offset;	/* offset in file filling in */
28 	xfs_extlen_t		length;	/* i/o length asked/allocated */
29 	xfs_fsblock_t		blkno;	/* starting block of new extent */
30 
31 	struct xfs_btree_cur	*cur;	/* btree cursor */
32 	struct xfs_iext_cursor	icur;	/* incore extent cursor */
33 	int			nallocs;/* number of extents alloc'd */
34 	int			logflags;/* flags for transaction logging */
35 
36 	xfs_extlen_t		total;	/* total blocks needed for xaction */
37 	xfs_extlen_t		minlen;	/* minimum allocation size (blocks) */
38 	xfs_extlen_t		minleft; /* amount must be left after alloc */
39 	bool			eof;	/* set if allocating past last extent */
40 	bool			wasdel;	/* replacing a delayed allocation */
41 	bool			aeof;	/* allocated space at eof */
42 	bool			conv;	/* overwriting unwritten extents */
43 	int			datatype;/* data type being allocated */
44 	int			flags;
45 };
46 
47 /*
48  * List of extents to be free "later".
49  * The list is kept sorted on xbf_startblock.
50  */
51 struct xfs_extent_free_item
52 {
53 	xfs_fsblock_t		xefi_startblock;/* starting fs block number */
54 	xfs_extlen_t		xefi_blockcount;/* number of blocks in extent */
55 	bool			xefi_skip_discard;
56 	struct list_head	xefi_list;
57 	struct xfs_owner_info	xefi_oinfo;	/* extent owner */
58 };
59 
60 #define	XFS_BMAP_MAX_NMAP	4
61 
62 /*
63  * Flags for xfs_bmapi_*
64  */
65 #define XFS_BMAPI_ENTIRE	0x001	/* return entire extent, not trimmed */
66 #define XFS_BMAPI_METADATA	0x002	/* mapping metadata not user data */
67 #define XFS_BMAPI_ATTRFORK	0x004	/* use attribute fork not data */
68 #define XFS_BMAPI_PREALLOC	0x008	/* preallocation op: unwritten space */
69 #define XFS_BMAPI_CONTIG	0x020	/* must allocate only one extent */
70 /*
71  * unwritten extent conversion - this needs write cache flushing and no additional
72  * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
73  * from written to unwritten, otherwise convert from unwritten to written.
74  */
75 #define XFS_BMAPI_CONVERT	0x040
76 
77 /*
78  * allocate zeroed extents - this requires all newly allocated user data extents
79  * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
80  * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
81  * during the allocation range to zeroed written extents.
82  */
83 #define XFS_BMAPI_ZERO		0x080
84 
85 /*
86  * Map the inode offset to the block given in ap->firstblock.  Primarily
87  * used for reflink.  The range must be in a hole, and this flag cannot be
88  * turned on with PREALLOC or CONVERT, and cannot be used on the attr fork.
89  *
90  * For bunmapi, this flag unmaps the range without adjusting quota, reducing
91  * refcount, or freeing the blocks.
92  */
93 #define XFS_BMAPI_REMAP		0x100
94 
95 /* Map something in the CoW fork. */
96 #define XFS_BMAPI_COWFORK	0x200
97 
98 /* Skip online discard of freed extents */
99 #define XFS_BMAPI_NODISCARD	0x1000
100 
101 /* Do not update the rmap btree.  Used for reconstructing bmbt from rmapbt. */
102 #define XFS_BMAPI_NORMAP	0x2000
103 
104 #define XFS_BMAPI_FLAGS \
105 	{ XFS_BMAPI_ENTIRE,	"ENTIRE" }, \
106 	{ XFS_BMAPI_METADATA,	"METADATA" }, \
107 	{ XFS_BMAPI_ATTRFORK,	"ATTRFORK" }, \
108 	{ XFS_BMAPI_PREALLOC,	"PREALLOC" }, \
109 	{ XFS_BMAPI_CONTIG,	"CONTIG" }, \
110 	{ XFS_BMAPI_CONVERT,	"CONVERT" }, \
111 	{ XFS_BMAPI_ZERO,	"ZERO" }, \
112 	{ XFS_BMAPI_REMAP,	"REMAP" }, \
113 	{ XFS_BMAPI_COWFORK,	"COWFORK" }, \
114 	{ XFS_BMAPI_NODISCARD,	"NODISCARD" }, \
115 	{ XFS_BMAPI_NORMAP,	"NORMAP" }
116 
117 
118 static inline int xfs_bmapi_aflag(int w)
119 {
120 	return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK :
121 	       (w == XFS_COW_FORK ? XFS_BMAPI_COWFORK : 0));
122 }
123 
124 static inline int xfs_bmapi_whichfork(int bmapi_flags)
125 {
126 	if (bmapi_flags & XFS_BMAPI_COWFORK)
127 		return XFS_COW_FORK;
128 	else if (bmapi_flags & XFS_BMAPI_ATTRFORK)
129 		return XFS_ATTR_FORK;
130 	return XFS_DATA_FORK;
131 }
132 
133 /*
134  * Special values for xfs_bmbt_irec_t br_startblock field.
135  */
136 #define	DELAYSTARTBLOCK		((xfs_fsblock_t)-1LL)
137 #define	HOLESTARTBLOCK		((xfs_fsblock_t)-2LL)
138 
139 /*
140  * Flags for xfs_bmap_add_extent*.
141  */
142 #define BMAP_LEFT_CONTIG	(1 << 0)
143 #define BMAP_RIGHT_CONTIG	(1 << 1)
144 #define BMAP_LEFT_FILLING	(1 << 2)
145 #define BMAP_RIGHT_FILLING	(1 << 3)
146 #define BMAP_LEFT_DELAY		(1 << 4)
147 #define BMAP_RIGHT_DELAY	(1 << 5)
148 #define BMAP_LEFT_VALID		(1 << 6)
149 #define BMAP_RIGHT_VALID	(1 << 7)
150 #define BMAP_ATTRFORK		(1 << 8)
151 #define BMAP_COWFORK		(1 << 9)
152 
153 #define XFS_BMAP_EXT_FLAGS \
154 	{ BMAP_LEFT_CONTIG,	"LC" }, \
155 	{ BMAP_RIGHT_CONTIG,	"RC" }, \
156 	{ BMAP_LEFT_FILLING,	"LF" }, \
157 	{ BMAP_RIGHT_FILLING,	"RF" }, \
158 	{ BMAP_ATTRFORK,	"ATTR" }, \
159 	{ BMAP_COWFORK,		"COW" }
160 
161 /* Return true if the extent is an allocated extent, written or not. */
162 static inline bool xfs_bmap_is_real_extent(struct xfs_bmbt_irec *irec)
163 {
164 	return irec->br_startblock != HOLESTARTBLOCK &&
165 		irec->br_startblock != DELAYSTARTBLOCK &&
166 		!isnullstartblock(irec->br_startblock);
167 }
168 
169 /*
170  * Return true if the extent is a real, allocated extent, or false if it is  a
171  * delayed allocation, and unwritten extent or a hole.
172  */
173 static inline bool xfs_bmap_is_written_extent(struct xfs_bmbt_irec *irec)
174 {
175 	return xfs_bmap_is_real_extent(irec) &&
176 	       irec->br_state != XFS_EXT_UNWRITTEN;
177 }
178 
179 /*
180  * Check the mapping for obviously garbage allocations that could trash the
181  * filesystem immediately.
182  */
183 #define xfs_valid_startblock(ip, startblock) \
184 	((startblock) != 0 || XFS_IS_REALTIME_INODE(ip))
185 
186 void	xfs_trim_extent(struct xfs_bmbt_irec *irec, xfs_fileoff_t bno,
187 		xfs_filblks_t len);
188 unsigned int xfs_bmap_compute_attr_offset(struct xfs_mount *mp);
189 int	xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
190 void	xfs_bmap_local_to_extents_empty(struct xfs_trans *tp,
191 		struct xfs_inode *ip, int whichfork);
192 void	__xfs_bmap_add_free(struct xfs_trans *tp, xfs_fsblock_t bno,
193 		xfs_filblks_t len, const struct xfs_owner_info *oinfo,
194 		bool skip_discard);
195 void	xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
196 int	xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
197 		xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
198 int	xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
199 		xfs_fileoff_t *last_block, int whichfork);
200 int	xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
201 		int whichfork);
202 int	xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
203 		xfs_filblks_t len, struct xfs_bmbt_irec *mval,
204 		int *nmap, int flags);
205 int	xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
206 		xfs_fileoff_t bno, xfs_filblks_t len, int flags,
207 		xfs_extlen_t total, struct xfs_bmbt_irec *mval, int *nmap);
208 int	__xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
209 		xfs_fileoff_t bno, xfs_filblks_t *rlen, int flags,
210 		xfs_extnum_t nexts);
211 int	xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
212 		xfs_fileoff_t bno, xfs_filblks_t len, int flags,
213 		xfs_extnum_t nexts, int *done);
214 int	xfs_bmap_del_extent_delay(struct xfs_inode *ip, int whichfork,
215 		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
216 		struct xfs_bmbt_irec *del);
217 void	xfs_bmap_del_extent_cow(struct xfs_inode *ip,
218 		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
219 		struct xfs_bmbt_irec *del);
220 uint	xfs_default_attroffset(struct xfs_inode *ip);
221 int	xfs_bmap_collapse_extents(struct xfs_trans *tp, struct xfs_inode *ip,
222 		xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
223 		bool *done);
224 int	xfs_bmap_can_insert_extents(struct xfs_inode *ip, xfs_fileoff_t off,
225 		xfs_fileoff_t shift);
226 int	xfs_bmap_insert_extents(struct xfs_trans *tp, struct xfs_inode *ip,
227 		xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
228 		bool *done, xfs_fileoff_t stop_fsb);
229 int	xfs_bmap_split_extent(struct xfs_trans *tp, struct xfs_inode *ip,
230 		xfs_fileoff_t split_offset);
231 int	xfs_bmapi_reserve_delalloc(struct xfs_inode *ip, int whichfork,
232 		xfs_fileoff_t off, xfs_filblks_t len, xfs_filblks_t prealloc,
233 		struct xfs_bmbt_irec *got, struct xfs_iext_cursor *cur,
234 		int eof);
235 int	xfs_bmapi_convert_delalloc(struct xfs_inode *ip, int whichfork,
236 		xfs_off_t offset, struct iomap *iomap, unsigned int *seq);
237 int	xfs_bmap_add_extent_unwritten_real(struct xfs_trans *tp,
238 		struct xfs_inode *ip, int whichfork,
239 		struct xfs_iext_cursor *icur, struct xfs_btree_cur **curp,
240 		struct xfs_bmbt_irec *new, int *logflagsp);
241 
242 static inline void
243 xfs_bmap_add_free(
244 	struct xfs_trans		*tp,
245 	xfs_fsblock_t			bno,
246 	xfs_filblks_t			len,
247 	const struct xfs_owner_info	*oinfo)
248 {
249 	__xfs_bmap_add_free(tp, bno, len, oinfo, false);
250 }
251 
252 enum xfs_bmap_intent_type {
253 	XFS_BMAP_MAP = 1,
254 	XFS_BMAP_UNMAP,
255 };
256 
257 struct xfs_bmap_intent {
258 	struct list_head			bi_list;
259 	enum xfs_bmap_intent_type		bi_type;
260 	struct xfs_inode			*bi_owner;
261 	int					bi_whichfork;
262 	struct xfs_bmbt_irec			bi_bmap;
263 };
264 
265 int	xfs_bmap_finish_one(struct xfs_trans *tp, struct xfs_inode *ip,
266 		enum xfs_bmap_intent_type type, int whichfork,
267 		xfs_fileoff_t startoff, xfs_fsblock_t startblock,
268 		xfs_filblks_t *blockcount, xfs_exntst_t state);
269 void	xfs_bmap_map_extent(struct xfs_trans *tp, struct xfs_inode *ip,
270 		struct xfs_bmbt_irec *imap);
271 void	xfs_bmap_unmap_extent(struct xfs_trans *tp, struct xfs_inode *ip,
272 		struct xfs_bmbt_irec *imap);
273 
274 static inline int xfs_bmap_fork_to_state(int whichfork)
275 {
276 	switch (whichfork) {
277 	case XFS_ATTR_FORK:
278 		return BMAP_ATTRFORK;
279 	case XFS_COW_FORK:
280 		return BMAP_COWFORK;
281 	default:
282 		return 0;
283 	}
284 }
285 
286 xfs_failaddr_t xfs_bmap_validate_extent(struct xfs_inode *ip, int whichfork,
287 		struct xfs_bmbt_irec *irec);
288 
289 int	xfs_bmapi_remap(struct xfs_trans *tp, struct xfs_inode *ip,
290 		xfs_fileoff_t bno, xfs_filblks_t len, xfs_fsblock_t startblock,
291 		int flags);
292 
293 #endif	/* __XFS_BMAP_H__ */
294