1 /* 2 * Copyright (c) 2000-2003,2005 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_INODE_FORK_H__ 19 #define __XFS_INODE_FORK_H__ 20 21 struct xfs_inode_log_item; 22 struct xfs_dinode; 23 24 /* 25 * The following xfs_ext_irec_t struct introduces a second (top) level 26 * to the in-core extent allocation scheme. These structs are allocated 27 * in a contiguous block, creating an indirection array where each entry 28 * (irec) contains a pointer to a buffer of in-core extent records which 29 * it manages. Each extent buffer is 4k in size, since 4k is the system 30 * page size on Linux i386 and systems with larger page sizes don't seem 31 * to gain much, if anything, by using their native page size as the 32 * extent buffer size. Also, using 4k extent buffers everywhere provides 33 * a consistent interface for CXFS across different platforms. 34 * 35 * There is currently no limit on the number of irec's (extent lists) 36 * allowed, so heavily fragmented files may require an indirection array 37 * which spans multiple system pages of memory. The number of extents 38 * which would require this amount of contiguous memory is very large 39 * and should not cause problems in the foreseeable future. However, 40 * if the memory needed for the contiguous array ever becomes a problem, 41 * it is possible that a third level of indirection may be required. 42 */ 43 typedef struct xfs_ext_irec { 44 xfs_bmbt_rec_host_t *er_extbuf; /* block of extent records */ 45 xfs_extnum_t er_extoff; /* extent offset in file */ 46 xfs_extnum_t er_extcount; /* number of extents in page/block */ 47 } xfs_ext_irec_t; 48 49 /* 50 * File incore extent information, present for each of data & attr forks. 51 */ 52 #define XFS_IEXT_BUFSZ 4096 53 #define XFS_LINEAR_EXTS (XFS_IEXT_BUFSZ / (uint)sizeof(xfs_bmbt_rec_t)) 54 #define XFS_INLINE_EXTS 2 55 #define XFS_INLINE_DATA 32 56 typedef struct xfs_ifork { 57 int if_bytes; /* bytes in if_u1 */ 58 int if_real_bytes; /* bytes allocated in if_u1 */ 59 struct xfs_btree_block *if_broot; /* file's incore btree root */ 60 short if_broot_bytes; /* bytes allocated for root */ 61 unsigned char if_flags; /* per-fork flags */ 62 union { 63 xfs_bmbt_rec_host_t *if_extents;/* linear map file exts */ 64 xfs_ext_irec_t *if_ext_irec; /* irec map file exts */ 65 char *if_data; /* inline file data */ 66 } if_u1; 67 union { 68 xfs_bmbt_rec_host_t if_inline_ext[XFS_INLINE_EXTS]; 69 /* very small file extents */ 70 char if_inline_data[XFS_INLINE_DATA]; 71 /* very small file data */ 72 xfs_dev_t if_rdev; /* dev number if special */ 73 uuid_t if_uuid; /* mount point value */ 74 } if_u2; 75 } xfs_ifork_t; 76 77 /* 78 * Per-fork incore inode flags. 79 */ 80 #define XFS_IFINLINE 0x01 /* Inline data is read in */ 81 #define XFS_IFEXTENTS 0x02 /* All extent pointers are read in */ 82 #define XFS_IFBROOT 0x04 /* i_broot points to the bmap b-tree root */ 83 #define XFS_IFEXTIREC 0x08 /* Indirection array of extent blocks */ 84 85 /* 86 * Fork handling. 87 */ 88 89 #define XFS_IFORK_Q(ip) ((ip)->i_d.di_forkoff != 0) 90 #define XFS_IFORK_BOFF(ip) ((int)((ip)->i_d.di_forkoff << 3)) 91 92 #define XFS_IFORK_PTR(ip,w) \ 93 ((w) == XFS_DATA_FORK ? \ 94 &(ip)->i_df : \ 95 ((w) == XFS_ATTR_FORK ? \ 96 (ip)->i_afp : \ 97 (ip)->i_cowfp)) 98 #define XFS_IFORK_DSIZE(ip) \ 99 (XFS_IFORK_Q(ip) ? \ 100 XFS_IFORK_BOFF(ip) : \ 101 XFS_LITINO((ip)->i_mount, (ip)->i_d.di_version)) 102 #define XFS_IFORK_ASIZE(ip) \ 103 (XFS_IFORK_Q(ip) ? \ 104 XFS_LITINO((ip)->i_mount, (ip)->i_d.di_version) - \ 105 XFS_IFORK_BOFF(ip) : \ 106 0) 107 #define XFS_IFORK_SIZE(ip,w) \ 108 ((w) == XFS_DATA_FORK ? \ 109 XFS_IFORK_DSIZE(ip) : \ 110 ((w) == XFS_ATTR_FORK ? \ 111 XFS_IFORK_ASIZE(ip) : \ 112 0)) 113 #define XFS_IFORK_FORMAT(ip,w) \ 114 ((w) == XFS_DATA_FORK ? \ 115 (ip)->i_d.di_format : \ 116 ((w) == XFS_ATTR_FORK ? \ 117 (ip)->i_d.di_aformat : \ 118 (ip)->i_cformat)) 119 #define XFS_IFORK_FMT_SET(ip,w,n) \ 120 ((w) == XFS_DATA_FORK ? \ 121 ((ip)->i_d.di_format = (n)) : \ 122 ((w) == XFS_ATTR_FORK ? \ 123 ((ip)->i_d.di_aformat = (n)) : \ 124 ((ip)->i_cformat = (n)))) 125 #define XFS_IFORK_NEXTENTS(ip,w) \ 126 ((w) == XFS_DATA_FORK ? \ 127 (ip)->i_d.di_nextents : \ 128 ((w) == XFS_ATTR_FORK ? \ 129 (ip)->i_d.di_anextents : \ 130 (ip)->i_cnextents)) 131 #define XFS_IFORK_NEXT_SET(ip,w,n) \ 132 ((w) == XFS_DATA_FORK ? \ 133 ((ip)->i_d.di_nextents = (n)) : \ 134 ((w) == XFS_ATTR_FORK ? \ 135 ((ip)->i_d.di_anextents = (n)) : \ 136 ((ip)->i_cnextents = (n)))) 137 #define XFS_IFORK_MAXEXT(ip, w) \ 138 (XFS_IFORK_SIZE(ip, w) / sizeof(xfs_bmbt_rec_t)) 139 140 struct xfs_ifork *xfs_iext_state_to_fork(struct xfs_inode *ip, int state); 141 142 int xfs_iformat_fork(struct xfs_inode *, struct xfs_dinode *); 143 void xfs_iflush_fork(struct xfs_inode *, struct xfs_dinode *, 144 struct xfs_inode_log_item *, int); 145 void xfs_idestroy_fork(struct xfs_inode *, int); 146 void xfs_idata_realloc(struct xfs_inode *, int, int); 147 void xfs_iroot_realloc(struct xfs_inode *, int, int); 148 int xfs_iread_extents(struct xfs_trans *, struct xfs_inode *, int); 149 int xfs_iextents_copy(struct xfs_inode *, struct xfs_bmbt_rec *, 150 int); 151 void xfs_init_local_fork(struct xfs_inode *, int, const void *, int); 152 153 struct xfs_bmbt_rec_host * 154 xfs_iext_get_ext(struct xfs_ifork *, xfs_extnum_t); 155 xfs_extnum_t xfs_iext_count(struct xfs_ifork *); 156 void xfs_iext_insert(struct xfs_inode *, xfs_extnum_t, xfs_extnum_t, 157 struct xfs_bmbt_irec *, int); 158 void xfs_iext_add(struct xfs_ifork *, xfs_extnum_t, int); 159 void xfs_iext_add_indirect_multi(struct xfs_ifork *, int, 160 xfs_extnum_t, int); 161 void xfs_iext_remove(struct xfs_inode *, xfs_extnum_t, int, int); 162 void xfs_iext_remove_inline(struct xfs_ifork *, xfs_extnum_t, int); 163 void xfs_iext_remove_direct(struct xfs_ifork *, xfs_extnum_t, int); 164 void xfs_iext_remove_indirect(struct xfs_ifork *, xfs_extnum_t, int); 165 void xfs_iext_realloc_direct(struct xfs_ifork *, int); 166 void xfs_iext_direct_to_inline(struct xfs_ifork *, xfs_extnum_t); 167 void xfs_iext_inline_to_direct(struct xfs_ifork *, int); 168 void xfs_iext_destroy(struct xfs_ifork *); 169 struct xfs_bmbt_rec_host * 170 xfs_iext_bno_to_ext(struct xfs_ifork *, xfs_fileoff_t, int *); 171 struct xfs_ext_irec * 172 xfs_iext_bno_to_irec(struct xfs_ifork *, xfs_fileoff_t, int *); 173 struct xfs_ext_irec * 174 xfs_iext_idx_to_irec(struct xfs_ifork *, xfs_extnum_t *, int *, 175 int); 176 void xfs_iext_irec_init(struct xfs_ifork *); 177 struct xfs_ext_irec * 178 xfs_iext_irec_new(struct xfs_ifork *, int); 179 void xfs_iext_irec_remove(struct xfs_ifork *, int); 180 void xfs_iext_irec_compact(struct xfs_ifork *); 181 void xfs_iext_irec_compact_pages(struct xfs_ifork *); 182 void xfs_iext_irec_compact_full(struct xfs_ifork *); 183 void xfs_iext_irec_update_extoffs(struct xfs_ifork *, int, int); 184 185 bool xfs_iext_lookup_extent(struct xfs_inode *ip, 186 struct xfs_ifork *ifp, xfs_fileoff_t bno, 187 xfs_extnum_t *idxp, struct xfs_bmbt_irec *gotp); 188 bool xfs_iext_get_extent(struct xfs_ifork *ifp, xfs_extnum_t idx, 189 struct xfs_bmbt_irec *gotp); 190 void xfs_iext_update_extent(struct xfs_ifork *ifp, xfs_extnum_t idx, 191 struct xfs_bmbt_irec *gotp); 192 193 extern struct kmem_zone *xfs_ifork_zone; 194 195 extern void xfs_ifork_init_cow(struct xfs_inode *ip); 196 197 #endif /* __XFS_INODE_FORK_H__ */ 198