xref: /openbmc/linux/fs/xfs/libxfs/xfs_bmap.h (revision 63705da3)
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 /*
17  * Argument structure for xfs_bmap_alloc.
18  */
19 struct xfs_bmalloca {
20 	struct xfs_trans	*tp;	/* transaction pointer */
21 	struct xfs_inode	*ip;	/* incore inode pointer */
22 	struct xfs_bmbt_irec	prev;	/* extent before the new one */
23 	struct xfs_bmbt_irec	got;	/* extent after, or delayed */
24 
25 	xfs_fileoff_t		offset;	/* offset in file filling in */
26 	xfs_extlen_t		length;	/* i/o length asked/allocated */
27 	xfs_fsblock_t		blkno;	/* starting block of new extent */
28 
29 	struct xfs_btree_cur	*cur;	/* btree cursor */
30 	struct xfs_iext_cursor	icur;	/* incore extent cursor */
31 	int			nallocs;/* number of extents alloc'd */
32 	int			logflags;/* flags for transaction logging */
33 
34 	xfs_extlen_t		total;	/* total blocks needed for xaction */
35 	xfs_extlen_t		minlen;	/* minimum allocation size (blocks) */
36 	xfs_extlen_t		minleft; /* amount must be left after alloc */
37 	bool			eof;	/* set if allocating past last extent */
38 	bool			wasdel;	/* replacing a delayed allocation */
39 	bool			aeof;	/* allocated space at eof */
40 	bool			conv;	/* overwriting unwritten extents */
41 	int			datatype;/* data type being allocated */
42 	int			flags;
43 };
44 
45 #define	XFS_BMAP_MAX_NMAP	4
46 
47 /*
48  * Flags for xfs_bmapi_*
49  */
50 #define XFS_BMAPI_ENTIRE	0x001	/* return entire extent, not trimmed */
51 #define XFS_BMAPI_METADATA	0x002	/* mapping metadata not user data */
52 #define XFS_BMAPI_ATTRFORK	0x004	/* use attribute fork not data */
53 #define XFS_BMAPI_PREALLOC	0x008	/* preallocation op: unwritten space */
54 #define XFS_BMAPI_CONTIG	0x020	/* must allocate only one extent */
55 /*
56  * unwritten extent conversion - this needs write cache flushing and no additional
57  * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
58  * from written to unwritten, otherwise convert from unwritten to written.
59  */
60 #define XFS_BMAPI_CONVERT	0x040
61 
62 /*
63  * allocate zeroed extents - this requires all newly allocated user data extents
64  * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
65  * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
66  * during the allocation range to zeroed written extents.
67  */
68 #define XFS_BMAPI_ZERO		0x080
69 
70 /*
71  * Map the inode offset to the block given in ap->firstblock.  Primarily
72  * used for reflink.  The range must be in a hole, and this flag cannot be
73  * turned on with PREALLOC or CONVERT, and cannot be used on the attr fork.
74  *
75  * For bunmapi, this flag unmaps the range without adjusting quota, reducing
76  * refcount, or freeing the blocks.
77  */
78 #define XFS_BMAPI_REMAP		0x100
79 
80 /* Map something in the CoW fork. */
81 #define XFS_BMAPI_COWFORK	0x200
82 
83 /* Skip online discard of freed extents */
84 #define XFS_BMAPI_NODISCARD	0x1000
85 
86 /* Do not update the rmap btree.  Used for reconstructing bmbt from rmapbt. */
87 #define XFS_BMAPI_NORMAP	0x2000
88 
89 #define XFS_BMAPI_FLAGS \
90 	{ XFS_BMAPI_ENTIRE,	"ENTIRE" }, \
91 	{ XFS_BMAPI_METADATA,	"METADATA" }, \
92 	{ XFS_BMAPI_ATTRFORK,	"ATTRFORK" }, \
93 	{ XFS_BMAPI_PREALLOC,	"PREALLOC" }, \
94 	{ XFS_BMAPI_CONTIG,	"CONTIG" }, \
95 	{ XFS_BMAPI_CONVERT,	"CONVERT" }, \
96 	{ XFS_BMAPI_ZERO,	"ZERO" }, \
97 	{ XFS_BMAPI_REMAP,	"REMAP" }, \
98 	{ XFS_BMAPI_COWFORK,	"COWFORK" }, \
99 	{ XFS_BMAPI_NODISCARD,	"NODISCARD" }, \
100 	{ XFS_BMAPI_NORMAP,	"NORMAP" }
101 
102 
103 static inline int xfs_bmapi_aflag(int w)
104 {
105 	return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK :
106 	       (w == XFS_COW_FORK ? XFS_BMAPI_COWFORK : 0));
107 }
108 
109 static inline int xfs_bmapi_whichfork(int bmapi_flags)
110 {
111 	if (bmapi_flags & XFS_BMAPI_COWFORK)
112 		return XFS_COW_FORK;
113 	else if (bmapi_flags & XFS_BMAPI_ATTRFORK)
114 		return XFS_ATTR_FORK;
115 	return XFS_DATA_FORK;
116 }
117 
118 /*
119  * Special values for xfs_bmbt_irec_t br_startblock field.
120  */
121 #define	DELAYSTARTBLOCK		((xfs_fsblock_t)-1LL)
122 #define	HOLESTARTBLOCK		((xfs_fsblock_t)-2LL)
123 
124 /*
125  * Flags for xfs_bmap_add_extent*.
126  */
127 #define BMAP_LEFT_CONTIG	(1 << 0)
128 #define BMAP_RIGHT_CONTIG	(1 << 1)
129 #define BMAP_LEFT_FILLING	(1 << 2)
130 #define BMAP_RIGHT_FILLING	(1 << 3)
131 #define BMAP_LEFT_DELAY		(1 << 4)
132 #define BMAP_RIGHT_DELAY	(1 << 5)
133 #define BMAP_LEFT_VALID		(1 << 6)
134 #define BMAP_RIGHT_VALID	(1 << 7)
135 #define BMAP_ATTRFORK		(1 << 8)
136 #define BMAP_COWFORK		(1 << 9)
137 
138 #define XFS_BMAP_EXT_FLAGS \
139 	{ BMAP_LEFT_CONTIG,	"LC" }, \
140 	{ BMAP_RIGHT_CONTIG,	"RC" }, \
141 	{ BMAP_LEFT_FILLING,	"LF" }, \
142 	{ BMAP_RIGHT_FILLING,	"RF" }, \
143 	{ BMAP_ATTRFORK,	"ATTR" }, \
144 	{ BMAP_COWFORK,		"COW" }
145 
146 /* Return true if the extent is an allocated extent, written or not. */
147 static inline bool xfs_bmap_is_real_extent(struct xfs_bmbt_irec *irec)
148 {
149 	return irec->br_startblock != HOLESTARTBLOCK &&
150 		irec->br_startblock != DELAYSTARTBLOCK &&
151 		!isnullstartblock(irec->br_startblock);
152 }
153 
154 /*
155  * Return true if the extent is a real, allocated extent, or false if it is  a
156  * delayed allocation, and unwritten extent or a hole.
157  */
158 static inline bool xfs_bmap_is_written_extent(struct xfs_bmbt_irec *irec)
159 {
160 	return xfs_bmap_is_real_extent(irec) &&
161 	       irec->br_state != XFS_EXT_UNWRITTEN;
162 }
163 
164 /*
165  * Check the mapping for obviously garbage allocations that could trash the
166  * filesystem immediately.
167  */
168 #define xfs_valid_startblock(ip, startblock) \
169 	((startblock) != 0 || XFS_IS_REALTIME_INODE(ip))
170 
171 void	xfs_trim_extent(struct xfs_bmbt_irec *irec, xfs_fileoff_t bno,
172 		xfs_filblks_t len);
173 unsigned int xfs_bmap_compute_attr_offset(struct xfs_mount *mp);
174 int	xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
175 void	xfs_bmap_local_to_extents_empty(struct xfs_trans *tp,
176 		struct xfs_inode *ip, int whichfork);
177 void	xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
178 int	xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
179 		xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
180 int	xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
181 		xfs_fileoff_t *last_block, int whichfork);
182 int	xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
183 		int whichfork);
184 int	xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
185 		xfs_filblks_t len, struct xfs_bmbt_irec *mval,
186 		int *nmap, int flags);
187 int	xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
188 		xfs_fileoff_t bno, xfs_filblks_t len, int flags,
189 		xfs_extlen_t total, struct xfs_bmbt_irec *mval, int *nmap);
190 int	__xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
191 		xfs_fileoff_t bno, xfs_filblks_t *rlen, int flags,
192 		xfs_extnum_t nexts);
193 int	xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
194 		xfs_fileoff_t bno, xfs_filblks_t len, int flags,
195 		xfs_extnum_t nexts, int *done);
196 int	xfs_bmap_del_extent_delay(struct xfs_inode *ip, int whichfork,
197 		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
198 		struct xfs_bmbt_irec *del);
199 void	xfs_bmap_del_extent_cow(struct xfs_inode *ip,
200 		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
201 		struct xfs_bmbt_irec *del);
202 uint	xfs_default_attroffset(struct xfs_inode *ip);
203 int	xfs_bmap_collapse_extents(struct xfs_trans *tp, struct xfs_inode *ip,
204 		xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
205 		bool *done);
206 int	xfs_bmap_can_insert_extents(struct xfs_inode *ip, xfs_fileoff_t off,
207 		xfs_fileoff_t shift);
208 int	xfs_bmap_insert_extents(struct xfs_trans *tp, struct xfs_inode *ip,
209 		xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
210 		bool *done, xfs_fileoff_t stop_fsb);
211 int	xfs_bmap_split_extent(struct xfs_trans *tp, struct xfs_inode *ip,
212 		xfs_fileoff_t split_offset);
213 int	xfs_bmapi_reserve_delalloc(struct xfs_inode *ip, int whichfork,
214 		xfs_fileoff_t off, xfs_filblks_t len, xfs_filblks_t prealloc,
215 		struct xfs_bmbt_irec *got, struct xfs_iext_cursor *cur,
216 		int eof);
217 int	xfs_bmapi_convert_delalloc(struct xfs_inode *ip, int whichfork,
218 		xfs_off_t offset, struct iomap *iomap, unsigned int *seq);
219 int	xfs_bmap_add_extent_unwritten_real(struct xfs_trans *tp,
220 		struct xfs_inode *ip, int whichfork,
221 		struct xfs_iext_cursor *icur, struct xfs_btree_cur **curp,
222 		struct xfs_bmbt_irec *new, int *logflagsp);
223 
224 enum xfs_bmap_intent_type {
225 	XFS_BMAP_MAP = 1,
226 	XFS_BMAP_UNMAP,
227 };
228 
229 struct xfs_bmap_intent {
230 	struct list_head			bi_list;
231 	enum xfs_bmap_intent_type		bi_type;
232 	int					bi_whichfork;
233 	struct xfs_inode			*bi_owner;
234 	struct xfs_bmbt_irec			bi_bmap;
235 };
236 
237 int	xfs_bmap_finish_one(struct xfs_trans *tp, struct xfs_inode *ip,
238 		enum xfs_bmap_intent_type type, int whichfork,
239 		xfs_fileoff_t startoff, xfs_fsblock_t startblock,
240 		xfs_filblks_t *blockcount, xfs_exntst_t state);
241 void	xfs_bmap_map_extent(struct xfs_trans *tp, struct xfs_inode *ip,
242 		struct xfs_bmbt_irec *imap);
243 void	xfs_bmap_unmap_extent(struct xfs_trans *tp, struct xfs_inode *ip,
244 		struct xfs_bmbt_irec *imap);
245 
246 static inline int xfs_bmap_fork_to_state(int whichfork)
247 {
248 	switch (whichfork) {
249 	case XFS_ATTR_FORK:
250 		return BMAP_ATTRFORK;
251 	case XFS_COW_FORK:
252 		return BMAP_COWFORK;
253 	default:
254 		return 0;
255 	}
256 }
257 
258 xfs_failaddr_t xfs_bmap_validate_extent(struct xfs_inode *ip, int whichfork,
259 		struct xfs_bmbt_irec *irec);
260 
261 int	xfs_bmapi_remap(struct xfs_trans *tp, struct xfs_inode *ip,
262 		xfs_fileoff_t bno, xfs_filblks_t len, xfs_fsblock_t startblock,
263 		int flags);
264 
265 extern struct kmem_cache	*xfs_bmap_intent_cache;
266 
267 int __init xfs_bmap_intent_init_cache(void);
268 void xfs_bmap_intent_destroy_cache(void);
269 
270 #endif	/* __XFS_BMAP_H__ */
271