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
  9struct xfs_inode_log_item;
 10struct xfs_dinode;
 11
 12/*
 13 * File incore extent information, present for each of data & attr forks.
 14 */
 15struct xfs_ifork {
 16	int64_t			if_bytes;	/* bytes in if_u1 */
 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	union {
 21		void		*if_root;	/* extent tree root */
 22		char		*if_data;	/* inline file data */
 23	} if_u1;
 24	xfs_extnum_t		if_nextents;	/* # of extents in this fork */
 25	short			if_broot_bytes;	/* bytes allocated for root */
 26	int8_t			if_format;	/* format of this fork */
 27};
 28
 29/*
 30 * Worst-case increase in the fork extent count when we're adding a single
 31 * extent to a fork and there's no possibility of splitting an existing mapping.
 32 */
 33#define XFS_IEXT_ADD_NOSPLIT_CNT	(1)
 34
 35/*
 36 * Punching out an extent from the middle of an existing extent can cause the
 37 * extent count to increase by 1.
 38 * i.e. | Old extent | Hole | Old extent |
 39 */
 40#define XFS_IEXT_PUNCH_HOLE_CNT		(1)
 41
 42/*
 43 * Adding/removing an xattr can cause XFS_DA_NODE_MAXDEPTH extents to
 44 * be added. One extra extent for dabtree in case a local attr is
 45 * large enough to cause a double split.  It can also cause extent
 46 * count to increase proportional to the size of a remote xattr's
 47 * value.
 48 */
 49#define XFS_IEXT_ATTR_MANIP_CNT(rmt_blks) \
 50	(XFS_DA_NODE_MAXDEPTH + max(1, rmt_blks))
 51
 52/*
 53 * A write to a sub-interval of an existing unwritten extent causes the original
 54 * extent to be split into 3 extents
 55 * i.e. | Unwritten | Real | Unwritten |
 56 * Hence extent count can increase by 2.
 57 */
 58#define XFS_IEXT_WRITE_UNWRITTEN_CNT	(2)
 59
 60
 61/*
 62 * Moving an extent to data fork can cause a sub-interval of an existing extent
 63 * to be unmapped. This will increase extent count by 1. Mapping in the new
 64 * extent can increase the extent count by 1 again i.e.
 65 * | Old extent | New extent | Old extent |
 66 * Hence number of extents increases by 2.
 67 */
 68#define XFS_IEXT_REFLINK_END_COW_CNT	(2)
 69
 70/*
 71 * Removing an initial range of source/donor file's extent and adding a new
 72 * extent (from donor/source file) in its place will cause extent count to
 73 * increase by 1.
 74 */
 75#define XFS_IEXT_SWAP_RMAP_CNT		(1)
 76
 77/*
 78 * Fork handling.
 79 */
 80#define XFS_IFORK_MAXEXT(ip, w) \
 81	(xfs_inode_fork_size(ip, w) / sizeof(xfs_bmbt_rec_t))
 82
 83static inline bool xfs_ifork_has_extents(struct xfs_ifork *ifp)
 84{
 85	return ifp->if_format == XFS_DINODE_FMT_EXTENTS ||
 86		ifp->if_format == XFS_DINODE_FMT_BTREE;
 87}
 88
 89static inline xfs_extnum_t xfs_ifork_nextents(struct xfs_ifork *ifp)
 90{
 91	if (!ifp)
 92		return 0;
 93	return ifp->if_nextents;
 94}
 95
 96static inline int8_t xfs_ifork_format(struct xfs_ifork *ifp)
 97{
 98	if (!ifp)
 99		return XFS_DINODE_FMT_EXTENTS;
100	return ifp->if_format;
101}
102
103static inline xfs_extnum_t xfs_iext_max_nextents(bool has_large_extent_counts,
104				int whichfork)
105{
106	switch (whichfork) {
107	case XFS_DATA_FORK:
108	case XFS_COW_FORK:
109		if (has_large_extent_counts)
110			return XFS_MAX_EXTCNT_DATA_FORK_LARGE;
111		return XFS_MAX_EXTCNT_DATA_FORK_SMALL;
112
113	case XFS_ATTR_FORK:
114		if (has_large_extent_counts)
115			return XFS_MAX_EXTCNT_ATTR_FORK_LARGE;
116		return XFS_MAX_EXTCNT_ATTR_FORK_SMALL;
117
118	default:
119		ASSERT(0);
120		return 0;
121	}
122}
123
124static inline xfs_extnum_t
125xfs_dfork_data_extents(
126	struct xfs_dinode	*dip)
127{
128	if (xfs_dinode_has_large_extent_counts(dip))
129		return be64_to_cpu(dip->di_big_nextents);
130
131	return be32_to_cpu(dip->di_nextents);
132}
133
134static inline xfs_extnum_t
135xfs_dfork_attr_extents(
136	struct xfs_dinode	*dip)
137{
138	if (xfs_dinode_has_large_extent_counts(dip))
139		return be32_to_cpu(dip->di_big_anextents);
140
141	return be16_to_cpu(dip->di_anextents);
142}
143
144static inline xfs_extnum_t
145xfs_dfork_nextents(
146	struct xfs_dinode	*dip,
147	int			whichfork)
148{
149	switch (whichfork) {
150	case XFS_DATA_FORK:
151		return xfs_dfork_data_extents(dip);
152	case XFS_ATTR_FORK:
153		return xfs_dfork_attr_extents(dip);
154	default:
155		ASSERT(0);
156		break;
157	}
158
159	return 0;
160}
161
162void xfs_ifork_zap_attr(struct xfs_inode *ip);
163void xfs_ifork_init_attr(struct xfs_inode *ip, enum xfs_dinode_fmt format,
164		xfs_extnum_t nextents);
165struct xfs_ifork *xfs_iext_state_to_fork(struct xfs_inode *ip, int state);
166
167int		xfs_iformat_data_fork(struct xfs_inode *, struct xfs_dinode *);
168int		xfs_iformat_attr_fork(struct xfs_inode *, struct xfs_dinode *);
169void		xfs_iflush_fork(struct xfs_inode *, struct xfs_dinode *,
170				struct xfs_inode_log_item *, int);
171void		xfs_idestroy_fork(struct xfs_ifork *ifp);
172void		xfs_idata_realloc(struct xfs_inode *ip, int64_t byte_diff,
173				int whichfork);
174void		xfs_iroot_realloc(struct xfs_inode *, int, int);
175int		xfs_iread_extents(struct xfs_trans *, struct xfs_inode *, int);
176int		xfs_iextents_copy(struct xfs_inode *, struct xfs_bmbt_rec *,
177				  int);
178void		xfs_init_local_fork(struct xfs_inode *ip, int whichfork,
179				const void *data, int64_t size);
180
181xfs_extnum_t	xfs_iext_count(struct xfs_ifork *ifp);
182void		xfs_iext_insert(struct xfs_inode *, struct xfs_iext_cursor *cur,
183			struct xfs_bmbt_irec *, int);
184void		xfs_iext_remove(struct xfs_inode *, struct xfs_iext_cursor *,
185			int);
186void		xfs_iext_destroy(struct xfs_ifork *);
187
188bool		xfs_iext_lookup_extent(struct xfs_inode *ip,
189			struct xfs_ifork *ifp, xfs_fileoff_t bno,
190			struct xfs_iext_cursor *cur,
191			struct xfs_bmbt_irec *gotp);
192bool		xfs_iext_lookup_extent_before(struct xfs_inode *ip,
193			struct xfs_ifork *ifp, xfs_fileoff_t *end,
194			struct xfs_iext_cursor *cur,
195			struct xfs_bmbt_irec *gotp);
196bool		xfs_iext_get_extent(struct xfs_ifork *ifp,
197			struct xfs_iext_cursor *cur,
198			struct xfs_bmbt_irec *gotp);
199void		xfs_iext_update_extent(struct xfs_inode *ip, int state,
200			struct xfs_iext_cursor *cur,
201			struct xfs_bmbt_irec *gotp);
202
203void		xfs_iext_first(struct xfs_ifork *, struct xfs_iext_cursor *);
204void		xfs_iext_last(struct xfs_ifork *, struct xfs_iext_cursor *);
205void		xfs_iext_next(struct xfs_ifork *, struct xfs_iext_cursor *);
206void		xfs_iext_prev(struct xfs_ifork *, struct xfs_iext_cursor *);
207
208static inline bool xfs_iext_next_extent(struct xfs_ifork *ifp,
209		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
210{
211	xfs_iext_next(ifp, cur);
212	return xfs_iext_get_extent(ifp, cur, gotp);
213}
214
215static inline bool xfs_iext_prev_extent(struct xfs_ifork *ifp,
216		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
217{
218	xfs_iext_prev(ifp, cur);
219	return xfs_iext_get_extent(ifp, cur, gotp);
220}
221
222/*
223 * Return the extent after cur in gotp without updating the cursor.
224 */
225static inline bool xfs_iext_peek_next_extent(struct xfs_ifork *ifp,
226		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
227{
228	struct xfs_iext_cursor ncur = *cur;
229
230	xfs_iext_next(ifp, &ncur);
231	return xfs_iext_get_extent(ifp, &ncur, gotp);
232}
233
234/*
235 * Return the extent before cur in gotp without updating the cursor.
236 */
237static inline bool xfs_iext_peek_prev_extent(struct xfs_ifork *ifp,
238		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
239{
240	struct xfs_iext_cursor ncur = *cur;
241
242	xfs_iext_prev(ifp, &ncur);
243	return xfs_iext_get_extent(ifp, &ncur, gotp);
244}
245
246#define for_each_xfs_iext(ifp, ext, got)		\
247	for (xfs_iext_first((ifp), (ext));		\
248	     xfs_iext_get_extent((ifp), (ext), (got));	\
249	     xfs_iext_next((ifp), (ext)))
250
251extern struct kmem_cache	*xfs_ifork_cache;
252
253extern void xfs_ifork_init_cow(struct xfs_inode *ip);
254
255int xfs_ifork_verify_local_data(struct xfs_inode *ip);
256int xfs_ifork_verify_local_attr(struct xfs_inode *ip);
257int xfs_iext_count_may_overflow(struct xfs_inode *ip, int whichfork,
258		int nr_to_add);
259int xfs_iext_count_upgrade(struct xfs_trans *tp, struct xfs_inode *ip,
260		uint nr_to_add);
261
262/* returns true if the fork has extents but they are not read in yet. */
263static inline bool xfs_need_iread_extents(struct xfs_ifork *ifp)
264{
265	return ifp->if_format == XFS_DINODE_FMT_BTREE && ifp->if_height == 0;
266}
267
268#endif	/* __XFS_INODE_FORK_H__ */