xref: /openbmc/linux/fs/xfs/libxfs/xfs_bmap.h (revision 6396bb221514d2876fd6dc0aa2a1f240d99b37bb)
1 /*
2  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3  * All Rights Reserved.
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it would be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write the Free Software Foundation,
16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  */
18 #ifndef __XFS_BMAP_H__
19 #define	__XFS_BMAP_H__
20 
21 struct getbmap;
22 struct xfs_bmbt_irec;
23 struct xfs_ifork;
24 struct xfs_inode;
25 struct xfs_mount;
26 struct xfs_trans;
27 
28 extern kmem_zone_t	*xfs_bmap_free_item_zone;
29 
30 /*
31  * Argument structure for xfs_bmap_alloc.
32  */
33 struct xfs_bmalloca {
34 	xfs_fsblock_t		*firstblock; /* i/o first block allocated */
35 	struct xfs_defer_ops	*dfops;	/* bmap freelist */
36 	struct xfs_trans	*tp;	/* transaction pointer */
37 	struct xfs_inode	*ip;	/* incore inode pointer */
38 	struct xfs_bmbt_irec	prev;	/* extent before the new one */
39 	struct xfs_bmbt_irec	got;	/* extent after, or delayed */
40 
41 	xfs_fileoff_t		offset;	/* offset in file filling in */
42 	xfs_extlen_t		length;	/* i/o length asked/allocated */
43 	xfs_fsblock_t		blkno;	/* starting block of new extent */
44 
45 	struct xfs_btree_cur	*cur;	/* btree cursor */
46 	struct xfs_iext_cursor	icur;	/* incore extent cursor */
47 	int			nallocs;/* number of extents alloc'd */
48 	int			logflags;/* flags for transaction logging */
49 
50 	xfs_extlen_t		total;	/* total blocks needed for xaction */
51 	xfs_extlen_t		minlen;	/* minimum allocation size (blocks) */
52 	xfs_extlen_t		minleft; /* amount must be left after alloc */
53 	bool			eof;	/* set if allocating past last extent */
54 	bool			wasdel;	/* replacing a delayed allocation */
55 	bool			aeof;	/* allocated space at eof */
56 	bool			conv;	/* overwriting unwritten extents */
57 	int			datatype;/* data type being allocated */
58 	int			flags;
59 };
60 
61 /*
62  * List of extents to be free "later".
63  * The list is kept sorted on xbf_startblock.
64  */
65 struct xfs_extent_free_item
66 {
67 	xfs_fsblock_t		xefi_startblock;/* starting fs block number */
68 	xfs_extlen_t		xefi_blockcount;/* number of blocks in extent */
69 	struct list_head	xefi_list;
70 	struct xfs_owner_info	xefi_oinfo;	/* extent owner */
71 	bool			xefi_skip_discard;
72 };
73 
74 #define	XFS_BMAP_MAX_NMAP	4
75 
76 /*
77  * Flags for xfs_bmapi_*
78  */
79 #define XFS_BMAPI_ENTIRE	0x001	/* return entire extent, not trimmed */
80 #define XFS_BMAPI_METADATA	0x002	/* mapping metadata not user data */
81 #define XFS_BMAPI_ATTRFORK	0x004	/* use attribute fork not data */
82 #define XFS_BMAPI_PREALLOC	0x008	/* preallocation op: unwritten space */
83 #define XFS_BMAPI_IGSTATE	0x010	/* Ignore state - */
84 					/* combine contig. space */
85 #define XFS_BMAPI_CONTIG	0x020	/* must allocate only one extent */
86 /*
87  * unwritten extent conversion - this needs write cache flushing and no additional
88  * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
89  * from written to unwritten, otherwise convert from unwritten to written.
90  */
91 #define XFS_BMAPI_CONVERT	0x040
92 
93 /*
94  * allocate zeroed extents - this requires all newly allocated user data extents
95  * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
96  * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
97  * during the allocation range to zeroed written extents.
98  */
99 #define XFS_BMAPI_ZERO		0x080
100 
101 /*
102  * Map the inode offset to the block given in ap->firstblock.  Primarily
103  * used for reflink.  The range must be in a hole, and this flag cannot be
104  * turned on with PREALLOC or CONVERT, and cannot be used on the attr fork.
105  *
106  * For bunmapi, this flag unmaps the range without adjusting quota, reducing
107  * refcount, or freeing the blocks.
108  */
109 #define XFS_BMAPI_REMAP		0x100
110 
111 /* Map something in the CoW fork. */
112 #define XFS_BMAPI_COWFORK	0x200
113 
114 /* Only convert delalloc space, don't allocate entirely new extents */
115 #define XFS_BMAPI_DELALLOC	0x400
116 
117 /* Only convert unwritten extents, don't allocate new blocks */
118 #define XFS_BMAPI_CONVERT_ONLY	0x800
119 
120 /* Skip online discard of freed extents */
121 #define XFS_BMAPI_NODISCARD	0x1000
122 
123 /* Do not update the rmap btree.  Used for reconstructing bmbt from rmapbt. */
124 #define XFS_BMAPI_NORMAP	0x2000
125 
126 #define XFS_BMAPI_FLAGS \
127 	{ XFS_BMAPI_ENTIRE,	"ENTIRE" }, \
128 	{ XFS_BMAPI_METADATA,	"METADATA" }, \
129 	{ XFS_BMAPI_ATTRFORK,	"ATTRFORK" }, \
130 	{ XFS_BMAPI_PREALLOC,	"PREALLOC" }, \
131 	{ XFS_BMAPI_IGSTATE,	"IGSTATE" }, \
132 	{ XFS_BMAPI_CONTIG,	"CONTIG" }, \
133 	{ XFS_BMAPI_CONVERT,	"CONVERT" }, \
134 	{ XFS_BMAPI_ZERO,	"ZERO" }, \
135 	{ XFS_BMAPI_REMAP,	"REMAP" }, \
136 	{ XFS_BMAPI_COWFORK,	"COWFORK" }, \
137 	{ XFS_BMAPI_DELALLOC,	"DELALLOC" }, \
138 	{ XFS_BMAPI_CONVERT_ONLY, "CONVERT_ONLY" }, \
139 	{ XFS_BMAPI_NODISCARD,	"NODISCARD" }, \
140 	{ XFS_BMAPI_NORMAP,	"NORMAP" }
141 
142 
143 static inline int xfs_bmapi_aflag(int w)
144 {
145 	return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK :
146 	       (w == XFS_COW_FORK ? XFS_BMAPI_COWFORK : 0));
147 }
148 
149 static inline int xfs_bmapi_whichfork(int bmapi_flags)
150 {
151 	if (bmapi_flags & XFS_BMAPI_COWFORK)
152 		return XFS_COW_FORK;
153 	else if (bmapi_flags & XFS_BMAPI_ATTRFORK)
154 		return XFS_ATTR_FORK;
155 	return XFS_DATA_FORK;
156 }
157 
158 /*
159  * Special values for xfs_bmbt_irec_t br_startblock field.
160  */
161 #define	DELAYSTARTBLOCK		((xfs_fsblock_t)-1LL)
162 #define	HOLESTARTBLOCK		((xfs_fsblock_t)-2LL)
163 
164 /*
165  * Flags for xfs_bmap_add_extent*.
166  */
167 #define BMAP_LEFT_CONTIG	(1 << 0)
168 #define BMAP_RIGHT_CONTIG	(1 << 1)
169 #define BMAP_LEFT_FILLING	(1 << 2)
170 #define BMAP_RIGHT_FILLING	(1 << 3)
171 #define BMAP_LEFT_DELAY		(1 << 4)
172 #define BMAP_RIGHT_DELAY	(1 << 5)
173 #define BMAP_LEFT_VALID		(1 << 6)
174 #define BMAP_RIGHT_VALID	(1 << 7)
175 #define BMAP_ATTRFORK		(1 << 8)
176 #define BMAP_COWFORK		(1 << 9)
177 
178 #define XFS_BMAP_EXT_FLAGS \
179 	{ BMAP_LEFT_CONTIG,	"LC" }, \
180 	{ BMAP_RIGHT_CONTIG,	"RC" }, \
181 	{ BMAP_LEFT_FILLING,	"LF" }, \
182 	{ BMAP_RIGHT_FILLING,	"RF" }, \
183 	{ BMAP_ATTRFORK,	"ATTR" }, \
184 	{ BMAP_COWFORK,		"COW" }
185 
186 
187 /*
188  * Return true if the extent is a real, allocated extent, or false if it is  a
189  * delayed allocation, and unwritten extent or a hole.
190  */
191 static inline bool xfs_bmap_is_real_extent(struct xfs_bmbt_irec *irec)
192 {
193 	return irec->br_state != XFS_EXT_UNWRITTEN &&
194 		irec->br_startblock != HOLESTARTBLOCK &&
195 		irec->br_startblock != DELAYSTARTBLOCK &&
196 		!isnullstartblock(irec->br_startblock);
197 }
198 
199 void	xfs_trim_extent(struct xfs_bmbt_irec *irec, xfs_fileoff_t bno,
200 		xfs_filblks_t len);
201 void	xfs_trim_extent_eof(struct xfs_bmbt_irec *, struct xfs_inode *);
202 int	xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
203 void	xfs_bmap_local_to_extents_empty(struct xfs_inode *ip, int whichfork);
204 void	__xfs_bmap_add_free(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
205 			  xfs_fsblock_t bno, xfs_filblks_t len,
206 			  struct xfs_owner_info *oinfo, bool skip_discard);
207 void	xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
208 int	xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
209 		xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
210 int	xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
211 		xfs_fileoff_t *last_block, int whichfork);
212 int	xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
213 		int whichfork);
214 int	xfs_bmap_one_block(struct xfs_inode *ip, int whichfork);
215 int	xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
216 		xfs_filblks_t len, struct xfs_bmbt_irec *mval,
217 		int *nmap, int flags);
218 int	xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
219 		xfs_fileoff_t bno, xfs_filblks_t len, int flags,
220 		xfs_fsblock_t *firstblock, xfs_extlen_t total,
221 		struct xfs_bmbt_irec *mval, int *nmap,
222 		struct xfs_defer_ops *dfops);
223 int	__xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
224 		xfs_fileoff_t bno, xfs_filblks_t *rlen, int flags,
225 		xfs_extnum_t nexts, xfs_fsblock_t *firstblock,
226 		struct xfs_defer_ops *dfops);
227 int	xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
228 		xfs_fileoff_t bno, xfs_filblks_t len, int flags,
229 		xfs_extnum_t nexts, xfs_fsblock_t *firstblock,
230 		struct xfs_defer_ops *dfops, int *done);
231 int	xfs_bmap_del_extent_delay(struct xfs_inode *ip, int whichfork,
232 		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
233 		struct xfs_bmbt_irec *del);
234 void	xfs_bmap_del_extent_cow(struct xfs_inode *ip,
235 		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
236 		struct xfs_bmbt_irec *del);
237 uint	xfs_default_attroffset(struct xfs_inode *ip);
238 int	xfs_bmap_collapse_extents(struct xfs_trans *tp, struct xfs_inode *ip,
239 		xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
240 		bool *done, xfs_fsblock_t *firstblock,
241 		struct xfs_defer_ops *dfops);
242 int	xfs_bmap_insert_extents(struct xfs_trans *tp, struct xfs_inode *ip,
243 		xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
244 		bool *done, xfs_fileoff_t stop_fsb, xfs_fsblock_t *firstblock,
245 		struct xfs_defer_ops *dfops);
246 int	xfs_bmap_split_extent(struct xfs_inode *ip, xfs_fileoff_t split_offset);
247 int	xfs_bmapi_reserve_delalloc(struct xfs_inode *ip, int whichfork,
248 		xfs_fileoff_t off, xfs_filblks_t len, xfs_filblks_t prealloc,
249 		struct xfs_bmbt_irec *got, struct xfs_iext_cursor *cur,
250 		int eof);
251 
252 static inline void
253 xfs_bmap_add_free(
254 	struct xfs_mount		*mp,
255 	struct xfs_defer_ops		*dfops,
256 	xfs_fsblock_t			bno,
257 	xfs_filblks_t			len,
258 	struct xfs_owner_info		*oinfo)
259 {
260 	__xfs_bmap_add_free(mp, dfops, bno, len, oinfo, false);
261 }
262 
263 enum xfs_bmap_intent_type {
264 	XFS_BMAP_MAP = 1,
265 	XFS_BMAP_UNMAP,
266 };
267 
268 struct xfs_bmap_intent {
269 	struct list_head			bi_list;
270 	enum xfs_bmap_intent_type		bi_type;
271 	struct xfs_inode			*bi_owner;
272 	int					bi_whichfork;
273 	struct xfs_bmbt_irec			bi_bmap;
274 };
275 
276 int	xfs_bmap_finish_one(struct xfs_trans *tp, struct xfs_defer_ops *dfops,
277 		struct xfs_inode *ip, enum xfs_bmap_intent_type type,
278 		int whichfork, xfs_fileoff_t startoff, xfs_fsblock_t startblock,
279 		xfs_filblks_t *blockcount, xfs_exntst_t state);
280 int	xfs_bmap_map_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
281 		struct xfs_inode *ip, struct xfs_bmbt_irec *imap);
282 int	xfs_bmap_unmap_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
283 		struct xfs_inode *ip, struct xfs_bmbt_irec *imap);
284 
285 static inline int xfs_bmap_fork_to_state(int whichfork)
286 {
287 	switch (whichfork) {
288 	case XFS_ATTR_FORK:
289 		return BMAP_ATTRFORK;
290 	case XFS_COW_FORK:
291 		return BMAP_COWFORK;
292 	default:
293 		return 0;
294 	}
295 }
296 
297 xfs_failaddr_t xfs_bmap_validate_extent(struct xfs_inode *ip, int whichfork,
298 		struct xfs_bmbt_irec *irec);
299 
300 int	xfs_bmapi_remap(struct xfs_trans *tp, struct xfs_inode *ip,
301 		xfs_fileoff_t bno, xfs_filblks_t len, xfs_fsblock_t startblock,
302 		struct xfs_defer_ops *dfops, int flags);
303 
304 #endif	/* __XFS_BMAP_H__ */
305