1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2017-2023 Oracle. All Rights Reserved. 4 * Author: Darrick J. Wong <djwong@kernel.org> 5 */ 6 #ifndef __XFS_SCRUB_SCRUB_H__ 7 #define __XFS_SCRUB_SCRUB_H__ 8 9 struct xfs_scrub; 10 11 struct xchk_relax { 12 unsigned long next_resched; 13 unsigned int resched_nr; 14 bool interruptible; 15 }; 16 17 /* Yield to the scheduler at most 10x per second. */ 18 #define XCHK_RELAX_NEXT (jiffies + (HZ / 10)) 19 20 #define INIT_XCHK_RELAX \ 21 (struct xchk_relax){ \ 22 .next_resched = XCHK_RELAX_NEXT, \ 23 .resched_nr = 0, \ 24 .interruptible = true, \ 25 } 26 27 /* 28 * Relax during a scrub operation and exit if there's a fatal signal pending. 29 * 30 * If preemption is disabled, we need to yield to the scheduler every now and 31 * then so that we don't run afoul of the soft lockup watchdog or RCU stall 32 * detector. cond_resched calls are somewhat expensive (~5ns) so we want to 33 * ratelimit this to 10x per second. Amortize the cost of the other checks by 34 * only doing it once every 100 calls. 35 */ 36 static inline int xchk_maybe_relax(struct xchk_relax *widget) 37 { 38 /* Amortize the cost of scheduling and checking signals. */ 39 if (likely(++widget->resched_nr < 100)) 40 return 0; 41 widget->resched_nr = 0; 42 43 if (unlikely(widget->next_resched <= jiffies)) { 44 cond_resched(); 45 widget->next_resched = XCHK_RELAX_NEXT; 46 } 47 48 if (widget->interruptible && fatal_signal_pending(current)) 49 return -EINTR; 50 51 return 0; 52 } 53 54 /* 55 * Standard flags for allocating memory within scrub. NOFS context is 56 * configured by the process allocation scope. Scrub and repair must be able 57 * to back out gracefully if there isn't enough memory. Force-cast to avoid 58 * complaints from static checkers. 59 */ 60 #define XCHK_GFP_FLAGS ((__force gfp_t)(GFP_KERNEL | __GFP_NOWARN | \ 61 __GFP_RETRY_MAYFAIL)) 62 63 /* 64 * For opening files by handle for fsck operations, we don't trust the inumber 65 * or the allocation state; therefore, perform an untrusted lookup. We don't 66 * want these inodes to pollute the cache, so mark them for immediate removal. 67 */ 68 #define XCHK_IGET_FLAGS (XFS_IGET_UNTRUSTED | XFS_IGET_DONTCACHE) 69 70 /* Type info and names for the scrub types. */ 71 enum xchk_type { 72 ST_NONE = 1, /* disabled */ 73 ST_PERAG, /* per-AG metadata */ 74 ST_FS, /* per-FS metadata */ 75 ST_INODE, /* per-inode metadata */ 76 ST_GENERIC, /* determined by the scrubber */ 77 ST_RTGROUP, /* rtgroup metadata */ 78 }; 79 80 struct xchk_meta_ops { 81 /* Acquire whatever resources are needed for the operation. */ 82 int (*setup)(struct xfs_scrub *sc); 83 84 /* Examine metadata for errors. */ 85 int (*scrub)(struct xfs_scrub *); 86 87 /* Repair or optimize the metadata. */ 88 int (*repair)(struct xfs_scrub *); 89 90 /* 91 * Re-scrub the metadata we repaired, in case there's extra work that 92 * we need to do to check our repair work. If this is NULL, we'll use 93 * the ->scrub function pointer, assuming that the regular scrub is 94 * sufficient. 95 */ 96 int (*repair_eval)(struct xfs_scrub *sc); 97 98 /* Decide if we even have this piece of metadata. */ 99 bool (*has)(struct xfs_mount *); 100 101 /* type describing required/allowed inputs */ 102 enum xchk_type type; 103 }; 104 105 /* Buffer pointers and btree cursors for an entire AG. */ 106 struct xchk_ag { 107 struct xfs_perag *pag; 108 109 /* AG btree roots */ 110 struct xfs_buf *agf_bp; 111 struct xfs_buf *agi_bp; 112 113 /* AG btrees */ 114 struct xfs_btree_cur *bno_cur; 115 struct xfs_btree_cur *cnt_cur; 116 struct xfs_btree_cur *ino_cur; 117 struct xfs_btree_cur *fino_cur; 118 struct xfs_btree_cur *rmap_cur; 119 struct xfs_btree_cur *refc_cur; 120 }; 121 122 /* Inode lock state for the RT volume. */ 123 struct xchk_rt { 124 /* incore rtgroup, if applicable */ 125 struct xfs_rtgroup *rtg; 126 127 /* XFS_RTGLOCK_* lock state if locked */ 128 unsigned int rtlock_flags; 129 }; 130 131 struct xfs_scrub { 132 /* General scrub state. */ 133 struct xfs_mount *mp; 134 struct xfs_scrub_metadata *sm; 135 const struct xchk_meta_ops *ops; 136 struct xfs_trans *tp; 137 138 /* File that scrub was called with. */ 139 struct file *file; 140 141 /* 142 * File that is undergoing the scrub operation. This can differ from 143 * the file that scrub was called with if we're checking file-based fs 144 * metadata (e.g. rt bitmaps) or if we're doing a scrub-by-handle for 145 * something that can't be opened directly (e.g. symlinks). 146 */ 147 struct xfs_inode *ip; 148 149 /* Kernel memory buffer used by scrubbers; freed at teardown. */ 150 void *buf; 151 152 /* 153 * Clean up resources owned by whatever is in the buffer. Cleanup can 154 * be deferred with this hook as a means for scrub functions to pass 155 * data to repair functions. This function must not free the buffer 156 * itself. 157 */ 158 void (*buf_cleanup)(void *buf); 159 160 /* xfile used by the scrubbers; freed at teardown. */ 161 struct xfile *xfile; 162 163 /* buffer target for in-memory btrees; also freed at teardown. */ 164 struct xfs_buftarg *xmbtp; 165 166 /* Lock flags for @ip. */ 167 uint ilock_flags; 168 169 /* The orphanage, for stashing files that have lost their parent. */ 170 uint orphanage_ilock_flags; 171 struct xfs_inode *orphanage; 172 173 /* A temporary file on this filesystem, for staging new metadata. */ 174 struct xfs_inode *tempip; 175 uint temp_ilock_flags; 176 177 /* See the XCHK/XREP state flags below. */ 178 unsigned int flags; 179 180 /* 181 * The XFS_SICK_* flags that correspond to the metadata being scrubbed 182 * or repaired. We will use this mask to update the in-core fs health 183 * status with whatever we find. 184 */ 185 unsigned int sick_mask; 186 187 /* next time we want to cond_resched() */ 188 struct xchk_relax relax; 189 190 /* State tracking for single-AG operations. */ 191 struct xchk_ag sa; 192 193 /* State tracking for realtime operations. */ 194 struct xchk_rt sr; 195 }; 196 197 /* XCHK state flags grow up from zero, XREP state flags grown down from 2^31 */ 198 #define XCHK_TRY_HARDER (1U << 0) /* can't get resources, try again */ 199 #define XCHK_HAVE_FREEZE_PROT (1U << 1) /* do we have freeze protection? */ 200 #define XCHK_FSGATES_DRAIN (1U << 2) /* defer ops draining enabled */ 201 #define XCHK_NEED_DRAIN (1U << 3) /* scrub needs to drain defer ops */ 202 #define XCHK_FSGATES_QUOTA (1U << 4) /* quota live update enabled */ 203 #define XCHK_FSGATES_DIRENTS (1U << 5) /* directory live update enabled */ 204 #define XCHK_FSGATES_RMAP (1U << 6) /* rmapbt live update enabled */ 205 #define XREP_RESET_PERAG_RESV (1U << 30) /* must reset AG space reservation */ 206 #define XREP_ALREADY_FIXED (1U << 31) /* checking our repair work */ 207 208 /* 209 * The XCHK_FSGATES* flags reflect functionality in the main filesystem that 210 * are only enabled for this particular online fsck. When not in use, the 211 * features are gated off via dynamic code patching, which is why the state 212 * must be enabled during scrub setup and can only be torn down afterwards. 213 */ 214 #define XCHK_FSGATES_ALL (XCHK_FSGATES_DRAIN | \ 215 XCHK_FSGATES_QUOTA | \ 216 XCHK_FSGATES_DIRENTS | \ 217 XCHK_FSGATES_RMAP) 218 219 struct xfs_scrub_subord { 220 struct xfs_scrub sc; 221 struct xfs_scrub *parent_sc; 222 unsigned int old_smtype; 223 unsigned int old_smflags; 224 }; 225 226 struct xfs_scrub_subord *xchk_scrub_create_subord(struct xfs_scrub *sc, 227 unsigned int subtype); 228 void xchk_scrub_free_subord(struct xfs_scrub_subord *sub); 229 230 /* 231 * We /could/ terminate a scrub/repair operation early. If we're not 232 * in a good place to continue (fatal signal, etc.) then bail out. 233 * Note that we're careful not to make any judgements about *error. 234 */ 235 static inline bool 236 xchk_should_terminate( 237 struct xfs_scrub *sc, 238 int *error) 239 { 240 if (xchk_maybe_relax(&sc->relax)) { 241 if (*error == 0) 242 *error = -EINTR; 243 return true; 244 } 245 return false; 246 } 247 248 static inline int xchk_nothing(struct xfs_scrub *sc) 249 { 250 return -ENOENT; 251 } 252 253 /* Metadata scrubbers */ 254 int xchk_tester(struct xfs_scrub *sc); 255 int xchk_superblock(struct xfs_scrub *sc); 256 int xchk_agf(struct xfs_scrub *sc); 257 int xchk_agfl(struct xfs_scrub *sc); 258 int xchk_agi(struct xfs_scrub *sc); 259 int xchk_allocbt(struct xfs_scrub *sc); 260 int xchk_iallocbt(struct xfs_scrub *sc); 261 int xchk_rmapbt(struct xfs_scrub *sc); 262 int xchk_refcountbt(struct xfs_scrub *sc); 263 int xchk_inode(struct xfs_scrub *sc); 264 int xchk_bmap_data(struct xfs_scrub *sc); 265 int xchk_bmap_attr(struct xfs_scrub *sc); 266 int xchk_bmap_cow(struct xfs_scrub *sc); 267 int xchk_directory(struct xfs_scrub *sc); 268 int xchk_xattr(struct xfs_scrub *sc); 269 int xchk_symlink(struct xfs_scrub *sc); 270 int xchk_parent(struct xfs_scrub *sc); 271 int xchk_dirtree(struct xfs_scrub *sc); 272 int xchk_metapath(struct xfs_scrub *sc); 273 #ifdef CONFIG_XFS_RT 274 int xchk_rtbitmap(struct xfs_scrub *sc); 275 int xchk_rtsummary(struct xfs_scrub *sc); 276 int xchk_rgsuperblock(struct xfs_scrub *sc); 277 #else 278 # define xchk_rtbitmap xchk_nothing 279 # define xchk_rtsummary xchk_nothing 280 # define xchk_rgsuperblock xchk_nothing 281 #endif 282 #ifdef CONFIG_XFS_QUOTA 283 int xchk_quota(struct xfs_scrub *sc); 284 int xchk_quotacheck(struct xfs_scrub *sc); 285 #else 286 # define xchk_quota xchk_nothing 287 # define xchk_quotacheck xchk_nothing 288 #endif 289 int xchk_fscounters(struct xfs_scrub *sc); 290 int xchk_nlinks(struct xfs_scrub *sc); 291 292 /* cross-referencing helpers */ 293 void xchk_xref_is_used_space(struct xfs_scrub *sc, xfs_agblock_t agbno, 294 xfs_extlen_t len); 295 void xchk_xref_is_not_inode_chunk(struct xfs_scrub *sc, xfs_agblock_t agbno, 296 xfs_extlen_t len); 297 void xchk_xref_is_inode_chunk(struct xfs_scrub *sc, xfs_agblock_t agbno, 298 xfs_extlen_t len); 299 void xchk_xref_is_only_owned_by(struct xfs_scrub *sc, xfs_agblock_t agbno, 300 xfs_extlen_t len, const struct xfs_owner_info *oinfo); 301 void xchk_xref_is_not_owned_by(struct xfs_scrub *sc, xfs_agblock_t agbno, 302 xfs_extlen_t len, const struct xfs_owner_info *oinfo); 303 void xchk_xref_has_no_owner(struct xfs_scrub *sc, xfs_agblock_t agbno, 304 xfs_extlen_t len); 305 void xchk_xref_is_cow_staging(struct xfs_scrub *sc, xfs_agblock_t bno, 306 xfs_extlen_t len); 307 void xchk_xref_is_not_shared(struct xfs_scrub *sc, xfs_agblock_t bno, 308 xfs_extlen_t len); 309 void xchk_xref_is_not_cow_staging(struct xfs_scrub *sc, xfs_agblock_t bno, 310 xfs_extlen_t len); 311 #ifdef CONFIG_XFS_RT 312 void xchk_xref_is_used_rt_space(struct xfs_scrub *sc, xfs_rtblock_t rtbno, 313 xfs_extlen_t len); 314 #else 315 # define xchk_xref_is_used_rt_space(sc, rtbno, len) do { } while (0) 316 #endif 317 318 #endif /* __XFS_SCRUB_SCRUB_H__ */ 319