xfs/libxfs/xfs_bmap.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 /*
0003  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
0004  * All Rights Reserved.
0005  */
0006 #ifndef __XFS_BMAP_H__
0007 #define __XFS_BMAP_H__
0008
0009 struct getbmap;
0010 struct xfs_bmbt_irec;
0011 struct xfs_ifork;
0012 struct xfs_inode;
0013 struct xfs_mount;
0014 struct xfs_trans;
0015
0016 /*
0017  * Argument structure for xfs_bmap_alloc.
0018  */
0019 struct xfs_bmalloca {
0020     struct xfs_trans    *tp;    /* transaction pointer */
0021     struct xfs_inode    *ip;    /* incore inode pointer */
0022     struct xfs_bmbt_irec    prev;   /* extent before the new one */
0023     struct xfs_bmbt_irec    got;    /* extent after, or delayed */
0024
0025     xfs_fileoff_t       offset; /* offset in file filling in */
0026     xfs_extlen_t        length; /* i/o length asked/allocated */
0027     xfs_fsblock_t       blkno;  /* starting block of new extent */
0028
0029     struct xfs_btree_cur    *cur;   /* btree cursor */
0030     struct xfs_iext_cursor  icur;   /* incore extent cursor */
0031     int         nallocs;/* number of extents alloc'd */
0032     int         logflags;/* flags for transaction logging */
0033
0034     xfs_extlen_t        total;  /* total blocks needed for xaction */
0035     xfs_extlen_t        minlen; /* minimum allocation size (blocks) */
0036     xfs_extlen_t        minleft; /* amount must be left after alloc */
0037     bool            eof;    /* set if allocating past last extent */
0038     bool            wasdel; /* replacing a delayed allocation */
0039     bool            aeof;   /* allocated space at eof */
0040     bool            conv;   /* overwriting unwritten extents */
0041     int         datatype;/* data type being allocated */
0042     uint32_t        flags;
0043 };
0044
0045 #define XFS_BMAP_MAX_NMAP   4
0046
0047 /*
0048  * Flags for xfs_bmapi_*
0049  */
0050 #define XFS_BMAPI_ENTIRE    (1u << 0) /* return entire extent untrimmed */
0051 #define XFS_BMAPI_METADATA  (1u << 1) /* mapping metadata not user data */
0052 #define XFS_BMAPI_ATTRFORK  (1u << 2) /* use attribute fork not data */
0053 #define XFS_BMAPI_PREALLOC  (1u << 3) /* preallocating unwritten space */
0054 #define XFS_BMAPI_CONTIG    (1u << 4) /* must allocate only one extent */
0055 /*
0056  * unwritten extent conversion - this needs write cache flushing and no additional
0057  * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
0058  * from written to unwritten, otherwise convert from unwritten to written.
0059  */
0060 #define XFS_BMAPI_CONVERT   (1u << 5)
0061
0062 /*
0063  * allocate zeroed extents - this requires all newly allocated user data extents
0064  * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
0065  * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
0066  * during the allocation range to zeroed written extents.
0067  */
0068 #define XFS_BMAPI_ZERO      (1u << 6)
0069
0070 /*
0071  * Map the inode offset to the block given in ap->firstblock.  Primarily
0072  * used for reflink.  The range must be in a hole, and this flag cannot be
0073  * turned on with PREALLOC or CONVERT, and cannot be used on the attr fork.
0074  *
0075  * For bunmapi, this flag unmaps the range without adjusting quota, reducing
0076  * refcount, or freeing the blocks.
0077  */
0078 #define XFS_BMAPI_REMAP     (1u << 7)
0079
0080 /* Map something in the CoW fork. */
0081 #define XFS_BMAPI_COWFORK   (1u << 8)
0082
0083 /* Skip online discard of freed extents */
0084 #define XFS_BMAPI_NODISCARD (1u << 9)
0085
0086 /* Do not update the rmap btree.  Used for reconstructing bmbt from rmapbt. */
0087 #define XFS_BMAPI_NORMAP    (1u << 10)
0088
0089 #define XFS_BMAPI_FLAGS \
0090     { XFS_BMAPI_ENTIRE, "ENTIRE" }, \
0091     { XFS_BMAPI_METADATA,   "METADATA" }, \
0092     { XFS_BMAPI_ATTRFORK,   "ATTRFORK" }, \
0093     { XFS_BMAPI_PREALLOC,   "PREALLOC" }, \
0094     { XFS_BMAPI_CONTIG, "CONTIG" }, \
0095     { XFS_BMAPI_CONVERT,    "CONVERT" }, \
0096     { XFS_BMAPI_ZERO,   "ZERO" }, \
0097     { XFS_BMAPI_REMAP,  "REMAP" }, \
0098     { XFS_BMAPI_COWFORK,    "COWFORK" }, \
0099     { XFS_BMAPI_NODISCARD,  "NODISCARD" }, \
0100     { XFS_BMAPI_NORMAP, "NORMAP" }
0101
0102
0103 static inline int xfs_bmapi_aflag(int w)
0104 {
0105     return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK :
0106            (w == XFS_COW_FORK ? XFS_BMAPI_COWFORK : 0));
0107 }
0108
0109 static inline int xfs_bmapi_whichfork(uint32_t bmapi_flags)
0110 {
0111     if (bmapi_flags & XFS_BMAPI_COWFORK)
0112         return XFS_COW_FORK;
0113     else if (bmapi_flags & XFS_BMAPI_ATTRFORK)
0114         return XFS_ATTR_FORK;
0115     return XFS_DATA_FORK;
0116 }
0117
0118 /*
0119  * Special values for xfs_bmbt_irec_t br_startblock field.
0120  */
0121 #define DELAYSTARTBLOCK     ((xfs_fsblock_t)-1LL)
0122 #define HOLESTARTBLOCK      ((xfs_fsblock_t)-2LL)
0123
0124 /*
0125  * Flags for xfs_bmap_add_extent*.
0126  */
0127 #define BMAP_LEFT_CONTIG    (1u << 0)
0128 #define BMAP_RIGHT_CONTIG   (1u << 1)
0129 #define BMAP_LEFT_FILLING   (1u << 2)
0130 #define BMAP_RIGHT_FILLING  (1u << 3)
0131 #define BMAP_LEFT_DELAY     (1u << 4)
0132 #define BMAP_RIGHT_DELAY    (1u << 5)
0133 #define BMAP_LEFT_VALID     (1u << 6)
0134 #define BMAP_RIGHT_VALID    (1u << 7)
0135 #define BMAP_ATTRFORK       (1u << 8)
0136 #define BMAP_COWFORK        (1u << 9)
0137
0138 #define XFS_BMAP_EXT_FLAGS \
0139     { BMAP_LEFT_CONTIG, "LC" }, \
0140     { BMAP_RIGHT_CONTIG,    "RC" }, \
0141     { BMAP_LEFT_FILLING,    "LF" }, \
0142     { BMAP_RIGHT_FILLING,   "RF" }, \
0143     { BMAP_ATTRFORK,    "ATTR" }, \
0144     { BMAP_COWFORK,     "COW" }
0145
0146 /* Return true if the extent is an allocated extent, written or not. */
0147 static inline bool xfs_bmap_is_real_extent(struct xfs_bmbt_irec *irec)
0148 {
0149     return irec->br_startblock != HOLESTARTBLOCK &&
0150         irec->br_startblock != DELAYSTARTBLOCK &&
0151         !isnullstartblock(irec->br_startblock);
0152 }
0153
0154 /*
0155  * Return true if the extent is a real, allocated extent, or false if it is  a
0156  * delayed allocation, and unwritten extent or a hole.
0157  */
0158 static inline bool xfs_bmap_is_written_extent(struct xfs_bmbt_irec *irec)
0159 {
0160     return xfs_bmap_is_real_extent(irec) &&
0161            irec->br_state != XFS_EXT_UNWRITTEN;
0162 }
0163
0164 /*
0165  * Check the mapping for obviously garbage allocations that could trash the
0166  * filesystem immediately.
0167  */
0168 #define xfs_valid_startblock(ip, startblock) \
0169     ((startblock) != 0 || XFS_IS_REALTIME_INODE(ip))
0170
0171 void    xfs_trim_extent(struct xfs_bmbt_irec *irec, xfs_fileoff_t bno,
0172         xfs_filblks_t len);
0173 unsigned int xfs_bmap_compute_attr_offset(struct xfs_mount *mp);
0174 int xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
0175 void    xfs_bmap_local_to_extents_empty(struct xfs_trans *tp,
0176         struct xfs_inode *ip, int whichfork);
0177 void    xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
0178 int xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
0179         xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
0180 int xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
0181         xfs_fileoff_t *last_block, int whichfork);
0182 int xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
0183         int whichfork);
0184 int xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
0185         xfs_filblks_t len, struct xfs_bmbt_irec *mval,
0186         int *nmap, uint32_t flags);
0187 int xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
0188         xfs_fileoff_t bno, xfs_filblks_t len, uint32_t flags,
0189         xfs_extlen_t total, struct xfs_bmbt_irec *mval, int *nmap);
0190 int __xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
0191         xfs_fileoff_t bno, xfs_filblks_t *rlen, uint32_t flags,
0192         xfs_extnum_t nexts);
0193 int xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
0194         xfs_fileoff_t bno, xfs_filblks_t len, uint32_t flags,
0195         xfs_extnum_t nexts, int *done);
0196 int xfs_bmap_del_extent_delay(struct xfs_inode *ip, int whichfork,
0197         struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
0198         struct xfs_bmbt_irec *del);
0199 void    xfs_bmap_del_extent_cow(struct xfs_inode *ip,
0200         struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *got,
0201         struct xfs_bmbt_irec *del);
0202 uint    xfs_default_attroffset(struct xfs_inode *ip);
0203 int xfs_bmap_collapse_extents(struct xfs_trans *tp, struct xfs_inode *ip,
0204         xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
0205         bool *done);
0206 int xfs_bmap_can_insert_extents(struct xfs_inode *ip, xfs_fileoff_t off,
0207         xfs_fileoff_t shift);
0208 int xfs_bmap_insert_extents(struct xfs_trans *tp, struct xfs_inode *ip,
0209         xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
0210         bool *done, xfs_fileoff_t stop_fsb);
0211 int xfs_bmap_split_extent(struct xfs_trans *tp, struct xfs_inode *ip,
0212         xfs_fileoff_t split_offset);
0213 int xfs_bmapi_reserve_delalloc(struct xfs_inode *ip, int whichfork,
0214         xfs_fileoff_t off, xfs_filblks_t len, xfs_filblks_t prealloc,
0215         struct xfs_bmbt_irec *got, struct xfs_iext_cursor *cur,
0216         int eof);
0217 int xfs_bmapi_convert_delalloc(struct xfs_inode *ip, int whichfork,
0218         xfs_off_t offset, struct iomap *iomap, unsigned int *seq);
0219 int xfs_bmap_add_extent_unwritten_real(struct xfs_trans *tp,
0220         struct xfs_inode *ip, int whichfork,
0221         struct xfs_iext_cursor *icur, struct xfs_btree_cur **curp,
0222         struct xfs_bmbt_irec *new, int *logflagsp);
0223
0224 enum xfs_bmap_intent_type {
0225     XFS_BMAP_MAP = 1,
0226     XFS_BMAP_UNMAP,
0227 };
0228
0229 struct xfs_bmap_intent {
0230     struct list_head            bi_list;
0231     enum xfs_bmap_intent_type       bi_type;
0232     int                 bi_whichfork;
0233     struct xfs_inode            *bi_owner;
0234     struct xfs_bmbt_irec            bi_bmap;
0235 };
0236
0237 int xfs_bmap_finish_one(struct xfs_trans *tp, struct xfs_inode *ip,
0238         enum xfs_bmap_intent_type type, int whichfork,
0239         xfs_fileoff_t startoff, xfs_fsblock_t startblock,
0240         xfs_filblks_t *blockcount, xfs_exntst_t state);
0241 void    xfs_bmap_map_extent(struct xfs_trans *tp, struct xfs_inode *ip,
0242         struct xfs_bmbt_irec *imap);
0243 void    xfs_bmap_unmap_extent(struct xfs_trans *tp, struct xfs_inode *ip,
0244         struct xfs_bmbt_irec *imap);
0245
0246 static inline uint32_t xfs_bmap_fork_to_state(int whichfork)
0247 {
0248     switch (whichfork) {
0249     case XFS_ATTR_FORK:
0250         return BMAP_ATTRFORK;
0251     case XFS_COW_FORK:
0252         return BMAP_COWFORK;
0253     default:
0254         return 0;
0255     }
0256 }
0257
0258 xfs_failaddr_t xfs_bmap_validate_extent(struct xfs_inode *ip, int whichfork,
0259         struct xfs_bmbt_irec *irec);
0260
0261 int xfs_bmapi_remap(struct xfs_trans *tp, struct xfs_inode *ip,
0262         xfs_fileoff_t bno, xfs_filblks_t len, xfs_fsblock_t startblock,
0263         uint32_t flags);
0264
0265 extern struct kmem_cache    *xfs_bmap_intent_cache;
0266
0267 int __init xfs_bmap_intent_init_cache(void);
0268 void xfs_bmap_intent_destroy_cache(void);
0269
0270 #endif  /* __XFS_BMAP_H__ */