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1// SPDX-License-Identifier: GPL-2.0+2/*3 * Copyright (C) 2017 Oracle. All Rights Reserved.4 * Author: Darrick J. Wong <darrick.wong@oracle.com>5 */6#include "xfs.h"7#include "xfs_fs.h"8#include "xfs_shared.h"9#include "xfs_format.h"10#include "xfs_log_format.h"11#include "xfs_trans_resv.h"12#include "xfs_mount.h"13#include "xfs_inode.h"14#include "xfs_trans.h"15#include "xfs_btree.h"16#include "xfs_rmap_btree.h"17#include "xfs_trace.h"18#include "xfs_rmap.h"19#include "xfs_alloc.h"20#include "xfs_bit.h"21#include <linux/fsmap.h>22#include "xfs_fsmap.h"23#include "xfs_refcount.h"24#include "xfs_refcount_btree.h"25#include "xfs_alloc_btree.h"26#include "xfs_rtbitmap.h"27#include "xfs_ag.h"28 29/* Convert an xfs_fsmap to an fsmap. */30static void31xfs_fsmap_from_internal(32 struct fsmap *dest,33 struct xfs_fsmap *src)34{35 dest->fmr_device = src->fmr_device;36 dest->fmr_flags = src->fmr_flags;37 dest->fmr_physical = BBTOB(src->fmr_physical);38 dest->fmr_owner = src->fmr_owner;39 dest->fmr_offset = BBTOB(src->fmr_offset);40 dest->fmr_length = BBTOB(src->fmr_length);41 dest->fmr_reserved[0] = 0;42 dest->fmr_reserved[1] = 0;43 dest->fmr_reserved[2] = 0;44}45 46/* Convert an fsmap to an xfs_fsmap. */47static void48xfs_fsmap_to_internal(49 struct xfs_fsmap *dest,50 struct fsmap *src)51{52 dest->fmr_device = src->fmr_device;53 dest->fmr_flags = src->fmr_flags;54 dest->fmr_physical = BTOBBT(src->fmr_physical);55 dest->fmr_owner = src->fmr_owner;56 dest->fmr_offset = BTOBBT(src->fmr_offset);57 dest->fmr_length = BTOBBT(src->fmr_length);58}59 60/* Convert an fsmap owner into an rmapbt owner. */61static int62xfs_fsmap_owner_to_rmap(63 struct xfs_rmap_irec *dest,64 const struct xfs_fsmap *src)65{66 if (!(src->fmr_flags & FMR_OF_SPECIAL_OWNER)) {67 dest->rm_owner = src->fmr_owner;68 return 0;69 }70 71 switch (src->fmr_owner) {72 case 0: /* "lowest owner id possible" */73 case -1ULL: /* "highest owner id possible" */74 dest->rm_owner = src->fmr_owner;75 break;76 case XFS_FMR_OWN_FREE:77 dest->rm_owner = XFS_RMAP_OWN_NULL;78 break;79 case XFS_FMR_OWN_UNKNOWN:80 dest->rm_owner = XFS_RMAP_OWN_UNKNOWN;81 break;82 case XFS_FMR_OWN_FS:83 dest->rm_owner = XFS_RMAP_OWN_FS;84 break;85 case XFS_FMR_OWN_LOG:86 dest->rm_owner = XFS_RMAP_OWN_LOG;87 break;88 case XFS_FMR_OWN_AG:89 dest->rm_owner = XFS_RMAP_OWN_AG;90 break;91 case XFS_FMR_OWN_INOBT:92 dest->rm_owner = XFS_RMAP_OWN_INOBT;93 break;94 case XFS_FMR_OWN_INODES:95 dest->rm_owner = XFS_RMAP_OWN_INODES;96 break;97 case XFS_FMR_OWN_REFC:98 dest->rm_owner = XFS_RMAP_OWN_REFC;99 break;100 case XFS_FMR_OWN_COW:101 dest->rm_owner = XFS_RMAP_OWN_COW;102 break;103 case XFS_FMR_OWN_DEFECTIVE: /* not implemented */104 /* fall through */105 default:106 return -EINVAL;107 }108 return 0;109}110 111/* Convert an rmapbt owner into an fsmap owner. */112static int113xfs_fsmap_owner_from_rmap(114 struct xfs_fsmap *dest,115 const struct xfs_rmap_irec *src)116{117 dest->fmr_flags = 0;118 if (!XFS_RMAP_NON_INODE_OWNER(src->rm_owner)) {119 dest->fmr_owner = src->rm_owner;120 return 0;121 }122 dest->fmr_flags |= FMR_OF_SPECIAL_OWNER;123 124 switch (src->rm_owner) {125 case XFS_RMAP_OWN_FS:126 dest->fmr_owner = XFS_FMR_OWN_FS;127 break;128 case XFS_RMAP_OWN_LOG:129 dest->fmr_owner = XFS_FMR_OWN_LOG;130 break;131 case XFS_RMAP_OWN_AG:132 dest->fmr_owner = XFS_FMR_OWN_AG;133 break;134 case XFS_RMAP_OWN_INOBT:135 dest->fmr_owner = XFS_FMR_OWN_INOBT;136 break;137 case XFS_RMAP_OWN_INODES:138 dest->fmr_owner = XFS_FMR_OWN_INODES;139 break;140 case XFS_RMAP_OWN_REFC:141 dest->fmr_owner = XFS_FMR_OWN_REFC;142 break;143 case XFS_RMAP_OWN_COW:144 dest->fmr_owner = XFS_FMR_OWN_COW;145 break;146 case XFS_RMAP_OWN_NULL: /* "free" */147 dest->fmr_owner = XFS_FMR_OWN_FREE;148 break;149 default:150 ASSERT(0);151 return -EFSCORRUPTED;152 }153 return 0;154}155 156/* getfsmap query state */157struct xfs_getfsmap_info {158 struct xfs_fsmap_head *head;159 struct fsmap *fsmap_recs; /* mapping records */160 struct xfs_buf *agf_bp; /* AGF, for refcount queries */161 struct xfs_perag *pag; /* AG info, if applicable */162 xfs_daddr_t next_daddr; /* next daddr we expect */163 /* daddr of low fsmap key when we're using the rtbitmap */164 xfs_daddr_t low_daddr;165 xfs_daddr_t end_daddr; /* daddr of high fsmap key */166 u64 missing_owner; /* owner of holes */167 u32 dev; /* device id */168 /*169 * Low rmap key for the query. If low.rm_blockcount is nonzero, this170 * is the second (or later) call to retrieve the recordset in pieces.171 * xfs_getfsmap_rec_before_start will compare all records retrieved172 * by the rmapbt query to filter out any records that start before173 * the last record.174 */175 struct xfs_rmap_irec low;176 struct xfs_rmap_irec high; /* high rmap key */177 bool last; /* last extent? */178};179 180/* Associate a device with a getfsmap handler. */181struct xfs_getfsmap_dev {182 u32 dev;183 int (*fn)(struct xfs_trans *tp,184 const struct xfs_fsmap *keys,185 struct xfs_getfsmap_info *info);186 sector_t nr_sectors;187};188 189/* Compare two getfsmap device handlers. */190static int191xfs_getfsmap_dev_compare(192 const void *p1,193 const void *p2)194{195 const struct xfs_getfsmap_dev *d1 = p1;196 const struct xfs_getfsmap_dev *d2 = p2;197 198 return d1->dev - d2->dev;199}200 201/* Decide if this mapping is shared. */202STATIC int203xfs_getfsmap_is_shared(204 struct xfs_trans *tp,205 struct xfs_getfsmap_info *info,206 const struct xfs_rmap_irec *rec,207 bool *stat)208{209 struct xfs_mount *mp = tp->t_mountp;210 struct xfs_btree_cur *cur;211 xfs_agblock_t fbno;212 xfs_extlen_t flen;213 int error;214 215 *stat = false;216 if (!xfs_has_reflink(mp))217 return 0;218 /* rt files will have no perag structure */219 if (!info->pag)220 return 0;221 222 /* Are there any shared blocks here? */223 flen = 0;224 cur = xfs_refcountbt_init_cursor(mp, tp, info->agf_bp, info->pag);225 226 error = xfs_refcount_find_shared(cur, rec->rm_startblock,227 rec->rm_blockcount, &fbno, &flen, false);228 229 xfs_btree_del_cursor(cur, error);230 if (error)231 return error;232 233 *stat = flen > 0;234 return 0;235}236 237static inline void238xfs_getfsmap_format(239 struct xfs_mount *mp,240 struct xfs_fsmap *xfm,241 struct xfs_getfsmap_info *info)242{243 struct fsmap *rec;244 245 trace_xfs_getfsmap_mapping(mp, xfm);246 247 rec = &info->fsmap_recs[info->head->fmh_entries++];248 xfs_fsmap_from_internal(rec, xfm);249}250 251static inline bool252xfs_getfsmap_rec_before_start(253 struct xfs_getfsmap_info *info,254 const struct xfs_rmap_irec *rec,255 xfs_daddr_t rec_daddr)256{257 if (info->low_daddr != XFS_BUF_DADDR_NULL)258 return rec_daddr < info->low_daddr;259 if (info->low.rm_blockcount)260 return xfs_rmap_compare(rec, &info->low) < 0;261 return false;262}263 264/*265 * Format a reverse mapping for getfsmap, having translated rm_startblock266 * into the appropriate daddr units. Pass in a nonzero @len_daddr if the267 * length could be larger than rm_blockcount in struct xfs_rmap_irec.268 */269STATIC int270xfs_getfsmap_helper(271 struct xfs_trans *tp,272 struct xfs_getfsmap_info *info,273 const struct xfs_rmap_irec *rec,274 xfs_daddr_t rec_daddr,275 xfs_daddr_t len_daddr)276{277 struct xfs_fsmap fmr;278 struct xfs_mount *mp = tp->t_mountp;279 bool shared;280 int error;281 282 if (fatal_signal_pending(current))283 return -EINTR;284 285 if (len_daddr == 0)286 len_daddr = XFS_FSB_TO_BB(mp, rec->rm_blockcount);287 288 /*289 * Filter out records that start before our startpoint, if the290 * caller requested that.291 */292 if (xfs_getfsmap_rec_before_start(info, rec, rec_daddr)) {293 rec_daddr += len_daddr;294 if (info->next_daddr < rec_daddr)295 info->next_daddr = rec_daddr;296 return 0;297 }298 299 /*300 * For an info->last query, we're looking for a gap between the last301 * mapping emitted and the high key specified by userspace. If the302 * user's query spans less than 1 fsblock, then info->high and303 * info->low will have the same rm_startblock, which causes rec_daddr304 * and next_daddr to be the same. Therefore, use the end_daddr that305 * we calculated from userspace's high key to synthesize the record.306 * Note that if the btree query found a mapping, there won't be a gap.307 */308 if (info->last && info->end_daddr != XFS_BUF_DADDR_NULL)309 rec_daddr = info->end_daddr;310 311 /* Are we just counting mappings? */312 if (info->head->fmh_count == 0) {313 if (info->head->fmh_entries == UINT_MAX)314 return -ECANCELED;315 316 if (rec_daddr > info->next_daddr)317 info->head->fmh_entries++;318 319 if (info->last)320 return 0;321 322 info->head->fmh_entries++;323 324 rec_daddr += len_daddr;325 if (info->next_daddr < rec_daddr)326 info->next_daddr = rec_daddr;327 return 0;328 }329 330 /*331 * If the record starts past the last physical block we saw,332 * then we've found a gap. Report the gap as being owned by333 * whatever the caller specified is the missing owner.334 */335 if (rec_daddr > info->next_daddr) {336 if (info->head->fmh_entries >= info->head->fmh_count)337 return -ECANCELED;338 339 fmr.fmr_device = info->dev;340 fmr.fmr_physical = info->next_daddr;341 fmr.fmr_owner = info->missing_owner;342 fmr.fmr_offset = 0;343 fmr.fmr_length = rec_daddr - info->next_daddr;344 fmr.fmr_flags = FMR_OF_SPECIAL_OWNER;345 xfs_getfsmap_format(mp, &fmr, info);346 }347 348 if (info->last)349 goto out;350 351 /* Fill out the extent we found */352 if (info->head->fmh_entries >= info->head->fmh_count)353 return -ECANCELED;354 355 trace_xfs_fsmap_mapping(mp, info->dev,356 info->pag ? info->pag->pag_agno : NULLAGNUMBER, rec);357 358 fmr.fmr_device = info->dev;359 fmr.fmr_physical = rec_daddr;360 error = xfs_fsmap_owner_from_rmap(&fmr, rec);361 if (error)362 return error;363 fmr.fmr_offset = XFS_FSB_TO_BB(mp, rec->rm_offset);364 fmr.fmr_length = len_daddr;365 if (rec->rm_flags & XFS_RMAP_UNWRITTEN)366 fmr.fmr_flags |= FMR_OF_PREALLOC;367 if (rec->rm_flags & XFS_RMAP_ATTR_FORK)368 fmr.fmr_flags |= FMR_OF_ATTR_FORK;369 if (rec->rm_flags & XFS_RMAP_BMBT_BLOCK)370 fmr.fmr_flags |= FMR_OF_EXTENT_MAP;371 if (fmr.fmr_flags == 0) {372 error = xfs_getfsmap_is_shared(tp, info, rec, &shared);373 if (error)374 return error;375 if (shared)376 fmr.fmr_flags |= FMR_OF_SHARED;377 }378 379 xfs_getfsmap_format(mp, &fmr, info);380out:381 rec_daddr += len_daddr;382 if (info->next_daddr < rec_daddr)383 info->next_daddr = rec_daddr;384 return 0;385}386 387/* Transform a rmapbt irec into a fsmap */388STATIC int389xfs_getfsmap_datadev_helper(390 struct xfs_btree_cur *cur,391 const struct xfs_rmap_irec *rec,392 void *priv)393{394 struct xfs_mount *mp = cur->bc_mp;395 struct xfs_getfsmap_info *info = priv;396 xfs_fsblock_t fsb;397 xfs_daddr_t rec_daddr;398 399 fsb = XFS_AGB_TO_FSB(mp, cur->bc_ag.pag->pag_agno, rec->rm_startblock);400 rec_daddr = XFS_FSB_TO_DADDR(mp, fsb);401 402 return xfs_getfsmap_helper(cur->bc_tp, info, rec, rec_daddr, 0);403}404 405/* Transform a bnobt irec into a fsmap */406STATIC int407xfs_getfsmap_datadev_bnobt_helper(408 struct xfs_btree_cur *cur,409 const struct xfs_alloc_rec_incore *rec,410 void *priv)411{412 struct xfs_mount *mp = cur->bc_mp;413 struct xfs_getfsmap_info *info = priv;414 struct xfs_rmap_irec irec;415 xfs_daddr_t rec_daddr;416 417 rec_daddr = XFS_AGB_TO_DADDR(mp, cur->bc_ag.pag->pag_agno,418 rec->ar_startblock);419 420 irec.rm_startblock = rec->ar_startblock;421 irec.rm_blockcount = rec->ar_blockcount;422 irec.rm_owner = XFS_RMAP_OWN_NULL; /* "free" */423 irec.rm_offset = 0;424 irec.rm_flags = 0;425 426 return xfs_getfsmap_helper(cur->bc_tp, info, &irec, rec_daddr, 0);427}428 429/* Set rmap flags based on the getfsmap flags */430static void431xfs_getfsmap_set_irec_flags(432 struct xfs_rmap_irec *irec,433 const struct xfs_fsmap *fmr)434{435 irec->rm_flags = 0;436 if (fmr->fmr_flags & FMR_OF_ATTR_FORK)437 irec->rm_flags |= XFS_RMAP_ATTR_FORK;438 if (fmr->fmr_flags & FMR_OF_EXTENT_MAP)439 irec->rm_flags |= XFS_RMAP_BMBT_BLOCK;440 if (fmr->fmr_flags & FMR_OF_PREALLOC)441 irec->rm_flags |= XFS_RMAP_UNWRITTEN;442}443 444static inline bool445rmap_not_shareable(struct xfs_mount *mp, const struct xfs_rmap_irec *r)446{447 if (!xfs_has_reflink(mp))448 return true;449 if (XFS_RMAP_NON_INODE_OWNER(r->rm_owner))450 return true;451 if (r->rm_flags & (XFS_RMAP_ATTR_FORK | XFS_RMAP_BMBT_BLOCK |452 XFS_RMAP_UNWRITTEN))453 return true;454 return false;455}456 457/* Execute a getfsmap query against the regular data device. */458STATIC int459__xfs_getfsmap_datadev(460 struct xfs_trans *tp,461 const struct xfs_fsmap *keys,462 struct xfs_getfsmap_info *info,463 int (*query_fn)(struct xfs_trans *,464 struct xfs_getfsmap_info *,465 struct xfs_btree_cur **,466 void *),467 void *priv)468{469 struct xfs_mount *mp = tp->t_mountp;470 struct xfs_perag *pag;471 struct xfs_btree_cur *bt_cur = NULL;472 xfs_fsblock_t start_fsb;473 xfs_fsblock_t end_fsb;474 xfs_agnumber_t start_ag;475 xfs_agnumber_t end_ag;476 uint64_t eofs;477 int error = 0;478 479 eofs = XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);480 if (keys[0].fmr_physical >= eofs)481 return 0;482 start_fsb = XFS_DADDR_TO_FSB(mp, keys[0].fmr_physical);483 end_fsb = XFS_DADDR_TO_FSB(mp, min(eofs - 1, keys[1].fmr_physical));484 485 /*486 * Convert the fsmap low/high keys to AG based keys. Initialize487 * low to the fsmap low key and max out the high key to the end488 * of the AG.489 */490 info->low.rm_offset = XFS_BB_TO_FSBT(mp, keys[0].fmr_offset);491 error = xfs_fsmap_owner_to_rmap(&info->low, &keys[0]);492 if (error)493 return error;494 info->low.rm_blockcount = XFS_BB_TO_FSBT(mp, keys[0].fmr_length);495 xfs_getfsmap_set_irec_flags(&info->low, &keys[0]);496 497 /* Adjust the low key if we are continuing from where we left off. */498 if (info->low.rm_blockcount == 0) {499 /* No previous record from which to continue */500 } else if (rmap_not_shareable(mp, &info->low)) {501 /* Last record seen was an unshareable extent */502 info->low.rm_owner = 0;503 info->low.rm_offset = 0;504 505 start_fsb += info->low.rm_blockcount;506 if (XFS_FSB_TO_DADDR(mp, start_fsb) >= eofs)507 return 0;508 } else {509 /* Last record seen was a shareable file data extent */510 info->low.rm_offset += info->low.rm_blockcount;511 }512 info->low.rm_startblock = XFS_FSB_TO_AGBNO(mp, start_fsb);513 514 info->high.rm_startblock = -1U;515 info->high.rm_owner = ULLONG_MAX;516 info->high.rm_offset = ULLONG_MAX;517 info->high.rm_blockcount = 0;518 info->high.rm_flags = XFS_RMAP_KEY_FLAGS | XFS_RMAP_REC_FLAGS;519 520 start_ag = XFS_FSB_TO_AGNO(mp, start_fsb);521 end_ag = XFS_FSB_TO_AGNO(mp, end_fsb);522 523 for_each_perag_range(mp, start_ag, end_ag, pag) {524 /*525 * Set the AG high key from the fsmap high key if this526 * is the last AG that we're querying.527 */528 info->pag = pag;529 if (pag->pag_agno == end_ag) {530 info->high.rm_startblock = XFS_FSB_TO_AGBNO(mp,531 end_fsb);532 info->high.rm_offset = XFS_BB_TO_FSBT(mp,533 keys[1].fmr_offset);534 error = xfs_fsmap_owner_to_rmap(&info->high, &keys[1]);535 if (error)536 break;537 xfs_getfsmap_set_irec_flags(&info->high, &keys[1]);538 }539 540 if (bt_cur) {541 xfs_btree_del_cursor(bt_cur, XFS_BTREE_NOERROR);542 bt_cur = NULL;543 xfs_trans_brelse(tp, info->agf_bp);544 info->agf_bp = NULL;545 }546 547 error = xfs_alloc_read_agf(pag, tp, 0, &info->agf_bp);548 if (error)549 break;550 551 trace_xfs_fsmap_low_key(mp, info->dev, pag->pag_agno,552 &info->low);553 trace_xfs_fsmap_high_key(mp, info->dev, pag->pag_agno,554 &info->high);555 556 error = query_fn(tp, info, &bt_cur, priv);557 if (error)558 break;559 560 /*561 * Set the AG low key to the start of the AG prior to562 * moving on to the next AG.563 */564 if (pag->pag_agno == start_ag)565 memset(&info->low, 0, sizeof(info->low));566 567 /*568 * If this is the last AG, report any gap at the end of it569 * before we drop the reference to the perag when the loop570 * terminates.571 */572 if (pag->pag_agno == end_ag) {573 info->last = true;574 error = query_fn(tp, info, &bt_cur, priv);575 if (error)576 break;577 }578 info->pag = NULL;579 }580 581 if (bt_cur)582 xfs_btree_del_cursor(bt_cur, error < 0 ? XFS_BTREE_ERROR :583 XFS_BTREE_NOERROR);584 if (info->agf_bp) {585 xfs_trans_brelse(tp, info->agf_bp);586 info->agf_bp = NULL;587 }588 if (info->pag) {589 xfs_perag_rele(info->pag);590 info->pag = NULL;591 } else if (pag) {592 /* loop termination case */593 xfs_perag_rele(pag);594 }595 596 return error;597}598 599/* Actually query the rmap btree. */600STATIC int601xfs_getfsmap_datadev_rmapbt_query(602 struct xfs_trans *tp,603 struct xfs_getfsmap_info *info,604 struct xfs_btree_cur **curpp,605 void *priv)606{607 /* Report any gap at the end of the last AG. */608 if (info->last)609 return xfs_getfsmap_datadev_helper(*curpp, &info->high, info);610 611 /* Allocate cursor for this AG and query_range it. */612 *curpp = xfs_rmapbt_init_cursor(tp->t_mountp, tp, info->agf_bp,613 info->pag);614 return xfs_rmap_query_range(*curpp, &info->low, &info->high,615 xfs_getfsmap_datadev_helper, info);616}617 618/* Execute a getfsmap query against the regular data device rmapbt. */619STATIC int620xfs_getfsmap_datadev_rmapbt(621 struct xfs_trans *tp,622 const struct xfs_fsmap *keys,623 struct xfs_getfsmap_info *info)624{625 info->missing_owner = XFS_FMR_OWN_FREE;626 return __xfs_getfsmap_datadev(tp, keys, info,627 xfs_getfsmap_datadev_rmapbt_query, NULL);628}629 630/* Actually query the bno btree. */631STATIC int632xfs_getfsmap_datadev_bnobt_query(633 struct xfs_trans *tp,634 struct xfs_getfsmap_info *info,635 struct xfs_btree_cur **curpp,636 void *priv)637{638 struct xfs_alloc_rec_incore *key = priv;639 640 /* Report any gap at the end of the last AG. */641 if (info->last)642 return xfs_getfsmap_datadev_bnobt_helper(*curpp, &key[1], info);643 644 /* Allocate cursor for this AG and query_range it. */645 *curpp = xfs_bnobt_init_cursor(tp->t_mountp, tp, info->agf_bp,646 info->pag);647 key->ar_startblock = info->low.rm_startblock;648 key[1].ar_startblock = info->high.rm_startblock;649 return xfs_alloc_query_range(*curpp, key, &key[1],650 xfs_getfsmap_datadev_bnobt_helper, info);651}652 653/* Execute a getfsmap query against the regular data device's bnobt. */654STATIC int655xfs_getfsmap_datadev_bnobt(656 struct xfs_trans *tp,657 const struct xfs_fsmap *keys,658 struct xfs_getfsmap_info *info)659{660 struct xfs_alloc_rec_incore akeys[2];661 662 memset(akeys, 0, sizeof(akeys));663 info->missing_owner = XFS_FMR_OWN_UNKNOWN;664 return __xfs_getfsmap_datadev(tp, keys, info,665 xfs_getfsmap_datadev_bnobt_query, &akeys[0]);666}667 668/* Execute a getfsmap query against the log device. */669STATIC int670xfs_getfsmap_logdev(671 struct xfs_trans *tp,672 const struct xfs_fsmap *keys,673 struct xfs_getfsmap_info *info)674{675 struct xfs_mount *mp = tp->t_mountp;676 struct xfs_rmap_irec rmap;677 xfs_daddr_t rec_daddr, len_daddr;678 xfs_fsblock_t start_fsb, end_fsb;679 uint64_t eofs;680 681 eofs = XFS_FSB_TO_BB(mp, mp->m_sb.sb_logblocks);682 if (keys[0].fmr_physical >= eofs)683 return 0;684 start_fsb = XFS_BB_TO_FSBT(mp,685 keys[0].fmr_physical + keys[0].fmr_length);686 end_fsb = XFS_BB_TO_FSB(mp, min(eofs - 1, keys[1].fmr_physical));687 688 /* Adjust the low key if we are continuing from where we left off. */689 if (keys[0].fmr_length > 0)690 info->low_daddr = XFS_FSB_TO_BB(mp, start_fsb);691 692 trace_xfs_fsmap_low_key_linear(mp, info->dev, start_fsb);693 trace_xfs_fsmap_high_key_linear(mp, info->dev, end_fsb);694 695 if (start_fsb > 0)696 return 0;697 698 /* Fabricate an rmap entry for the external log device. */699 rmap.rm_startblock = 0;700 rmap.rm_blockcount = mp->m_sb.sb_logblocks;701 rmap.rm_owner = XFS_RMAP_OWN_LOG;702 rmap.rm_offset = 0;703 rmap.rm_flags = 0;704 705 rec_daddr = XFS_FSB_TO_BB(mp, rmap.rm_startblock);706 len_daddr = XFS_FSB_TO_BB(mp, rmap.rm_blockcount);707 return xfs_getfsmap_helper(tp, info, &rmap, rec_daddr, len_daddr);708}709 710#ifdef CONFIG_XFS_RT711/* Transform a rtbitmap "record" into a fsmap */712STATIC int713xfs_getfsmap_rtdev_rtbitmap_helper(714 struct xfs_mount *mp,715 struct xfs_trans *tp,716 const struct xfs_rtalloc_rec *rec,717 void *priv)718{719 struct xfs_getfsmap_info *info = priv;720 struct xfs_rmap_irec irec;721 xfs_rtblock_t rtbno;722 xfs_daddr_t rec_daddr, len_daddr;723 724 rtbno = xfs_rtx_to_rtb(mp, rec->ar_startext);725 rec_daddr = XFS_FSB_TO_BB(mp, rtbno);726 irec.rm_startblock = rtbno;727 728 rtbno = xfs_rtx_to_rtb(mp, rec->ar_extcount);729 len_daddr = XFS_FSB_TO_BB(mp, rtbno);730 irec.rm_blockcount = rtbno;731 732 irec.rm_owner = XFS_RMAP_OWN_NULL; /* "free" */733 irec.rm_offset = 0;734 irec.rm_flags = 0;735 736 return xfs_getfsmap_helper(tp, info, &irec, rec_daddr, len_daddr);737}738 739/* Execute a getfsmap query against the realtime device rtbitmap. */740STATIC int741xfs_getfsmap_rtdev_rtbitmap(742 struct xfs_trans *tp,743 const struct xfs_fsmap *keys,744 struct xfs_getfsmap_info *info)745{746 747 struct xfs_rtalloc_rec ahigh = { 0 };748 struct xfs_mount *mp = tp->t_mountp;749 xfs_rtblock_t start_rtb;750 xfs_rtblock_t end_rtb;751 xfs_rtxnum_t high;752 uint64_t eofs;753 int error;754 755 eofs = XFS_FSB_TO_BB(mp, xfs_rtx_to_rtb(mp, mp->m_sb.sb_rextents));756 if (keys[0].fmr_physical >= eofs)757 return 0;758 start_rtb = XFS_BB_TO_FSBT(mp,759 keys[0].fmr_physical + keys[0].fmr_length);760 end_rtb = XFS_BB_TO_FSB(mp, min(eofs - 1, keys[1].fmr_physical));761 762 info->missing_owner = XFS_FMR_OWN_UNKNOWN;763 764 /* Adjust the low key if we are continuing from where we left off. */765 if (keys[0].fmr_length > 0) {766 info->low_daddr = XFS_FSB_TO_BB(mp, start_rtb);767 if (info->low_daddr >= eofs)768 return 0;769 }770 771 trace_xfs_fsmap_low_key_linear(mp, info->dev, start_rtb);772 trace_xfs_fsmap_high_key_linear(mp, info->dev, end_rtb);773 774 xfs_rtbitmap_lock_shared(mp, XFS_RBMLOCK_BITMAP);775 776 /*777 * Set up query parameters to return free rtextents covering the range778 * we want.779 */780 high = xfs_rtb_to_rtxup(mp, end_rtb);781 error = xfs_rtalloc_query_range(mp, tp, xfs_rtb_to_rtx(mp, start_rtb),782 high, xfs_getfsmap_rtdev_rtbitmap_helper, info);783 if (error)784 goto err;785 786 /*787 * Report any gaps at the end of the rtbitmap by simulating a null788 * rmap starting at the block after the end of the query range.789 */790 info->last = true;791 ahigh.ar_startext = min(mp->m_sb.sb_rextents, high);792 793 error = xfs_getfsmap_rtdev_rtbitmap_helper(mp, tp, &ahigh, info);794 if (error)795 goto err;796err:797 xfs_rtbitmap_unlock_shared(mp, XFS_RBMLOCK_BITMAP);798 return error;799}800#endif /* CONFIG_XFS_RT */801 802/* Do we recognize the device? */803STATIC bool804xfs_getfsmap_is_valid_device(805 struct xfs_mount *mp,806 struct xfs_fsmap *fm)807{808 if (fm->fmr_device == 0 || fm->fmr_device == UINT_MAX ||809 fm->fmr_device == new_encode_dev(mp->m_ddev_targp->bt_dev))810 return true;811 if (mp->m_logdev_targp &&812 fm->fmr_device == new_encode_dev(mp->m_logdev_targp->bt_dev))813 return true;814 if (mp->m_rtdev_targp &&815 fm->fmr_device == new_encode_dev(mp->m_rtdev_targp->bt_dev))816 return true;817 return false;818}819 820/* Ensure that the low key is less than the high key. */821STATIC bool822xfs_getfsmap_check_keys(823 struct xfs_fsmap *low_key,824 struct xfs_fsmap *high_key)825{826 if (low_key->fmr_flags & (FMR_OF_SPECIAL_OWNER | FMR_OF_EXTENT_MAP)) {827 if (low_key->fmr_offset)828 return false;829 }830 if (high_key->fmr_flags != -1U &&831 (high_key->fmr_flags & (FMR_OF_SPECIAL_OWNER |832 FMR_OF_EXTENT_MAP))) {833 if (high_key->fmr_offset && high_key->fmr_offset != -1ULL)834 return false;835 }836 if (high_key->fmr_length && high_key->fmr_length != -1ULL)837 return false;838 839 if (low_key->fmr_device > high_key->fmr_device)840 return false;841 if (low_key->fmr_device < high_key->fmr_device)842 return true;843 844 if (low_key->fmr_physical > high_key->fmr_physical)845 return false;846 if (low_key->fmr_physical < high_key->fmr_physical)847 return true;848 849 if (low_key->fmr_owner > high_key->fmr_owner)850 return false;851 if (low_key->fmr_owner < high_key->fmr_owner)852 return true;853 854 if (low_key->fmr_offset > high_key->fmr_offset)855 return false;856 if (low_key->fmr_offset < high_key->fmr_offset)857 return true;858 859 return false;860}861 862/*863 * There are only two devices if we didn't configure RT devices at build time.864 */865#ifdef CONFIG_XFS_RT866#define XFS_GETFSMAP_DEVS 3867#else868#define XFS_GETFSMAP_DEVS 2869#endif /* CONFIG_XFS_RT */870 871/*872 * Get filesystem's extents as described in head, and format for output. Fills873 * in the supplied records array until there are no more reverse mappings to874 * return or head.fmh_entries == head.fmh_count. In the second case, this875 * function returns -ECANCELED to indicate that more records would have been876 * returned.877 *878 * Key to Confusion879 * ----------------880 * There are multiple levels of keys and counters at work here:881 * xfs_fsmap_head.fmh_keys -- low and high fsmap keys passed in;882 * these reflect fs-wide sector addrs.883 * dkeys -- fmh_keys used to query each device;884 * these are fmh_keys but w/ the low key885 * bumped up by fmr_length.886 * xfs_getfsmap_info.next_daddr -- next disk addr we expect to see; this887 * is how we detect gaps in the fsmap888 records and report them.889 * xfs_getfsmap_info.low/high -- per-AG low/high keys computed from890 * dkeys; used to query the metadata.891 */892STATIC int893xfs_getfsmap(894 struct xfs_mount *mp,895 struct xfs_fsmap_head *head,896 struct fsmap *fsmap_recs)897{898 struct xfs_trans *tp = NULL;899 struct xfs_fsmap dkeys[2]; /* per-dev keys */900 struct xfs_getfsmap_dev handlers[XFS_GETFSMAP_DEVS];901 struct xfs_getfsmap_info info = { NULL };902 bool use_rmap;903 int i;904 int error = 0;905 906 if (head->fmh_iflags & ~FMH_IF_VALID)907 return -EINVAL;908 if (!xfs_getfsmap_is_valid_device(mp, &head->fmh_keys[0]) ||909 !xfs_getfsmap_is_valid_device(mp, &head->fmh_keys[1]))910 return -EINVAL;911 if (!xfs_getfsmap_check_keys(&head->fmh_keys[0], &head->fmh_keys[1]))912 return -EINVAL;913 914 use_rmap = xfs_has_rmapbt(mp) &&915 has_capability_noaudit(current, CAP_SYS_ADMIN);916 head->fmh_entries = 0;917 918 /* Set up our device handlers. */919 memset(handlers, 0, sizeof(handlers));920 handlers[0].nr_sectors = XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);921 handlers[0].dev = new_encode_dev(mp->m_ddev_targp->bt_dev);922 if (use_rmap)923 handlers[0].fn = xfs_getfsmap_datadev_rmapbt;924 else925 handlers[0].fn = xfs_getfsmap_datadev_bnobt;926 if (mp->m_logdev_targp != mp->m_ddev_targp) {927 handlers[1].nr_sectors = XFS_FSB_TO_BB(mp,928 mp->m_sb.sb_logblocks);929 handlers[1].dev = new_encode_dev(mp->m_logdev_targp->bt_dev);930 handlers[1].fn = xfs_getfsmap_logdev;931 }932#ifdef CONFIG_XFS_RT933 if (mp->m_rtdev_targp) {934 handlers[2].nr_sectors = XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);935 handlers[2].dev = new_encode_dev(mp->m_rtdev_targp->bt_dev);936 handlers[2].fn = xfs_getfsmap_rtdev_rtbitmap;937 }938#endif /* CONFIG_XFS_RT */939 940 xfs_sort(handlers, XFS_GETFSMAP_DEVS, sizeof(struct xfs_getfsmap_dev),941 xfs_getfsmap_dev_compare);942 943 /*944 * To continue where we left off, we allow userspace to use the945 * last mapping from a previous call as the low key of the next.946 * This is identified by a non-zero length in the low key. We947 * have to increment the low key in this scenario to ensure we948 * don't return the same mapping again, and instead return the949 * very next mapping.950 *951 * If the low key mapping refers to file data, the same physical952 * blocks could be mapped to several other files/offsets.953 * According to rmapbt record ordering, the minimal next954 * possible record for the block range is the next starting955 * offset in the same inode. Therefore, each fsmap backend bumps956 * the file offset to continue the search appropriately. For957 * all other low key mapping types (attr blocks, metadata), each958 * fsmap backend bumps the physical offset as there can be no959 * other mapping for the same physical block range.960 */961 dkeys[0] = head->fmh_keys[0];962 memset(&dkeys[1], 0xFF, sizeof(struct xfs_fsmap));963 964 info.next_daddr = head->fmh_keys[0].fmr_physical +965 head->fmh_keys[0].fmr_length;966 info.end_daddr = XFS_BUF_DADDR_NULL;967 info.fsmap_recs = fsmap_recs;968 info.head = head;969 970 /* For each device we support... */971 for (i = 0; i < XFS_GETFSMAP_DEVS; i++) {972 /* Is this device within the range the user asked for? */973 if (!handlers[i].fn)974 continue;975 if (head->fmh_keys[0].fmr_device > handlers[i].dev)976 continue;977 if (head->fmh_keys[1].fmr_device < handlers[i].dev)978 break;979 980 /*981 * If this device number matches the high key, we have982 * to pass the high key to the handler to limit the983 * query results. If the device number exceeds the984 * low key, zero out the low key so that we get985 * everything from the beginning.986 */987 if (handlers[i].dev == head->fmh_keys[1].fmr_device) {988 dkeys[1] = head->fmh_keys[1];989 info.end_daddr = min(handlers[i].nr_sectors - 1,990 dkeys[1].fmr_physical);991 }992 if (handlers[i].dev > head->fmh_keys[0].fmr_device)993 memset(&dkeys[0], 0, sizeof(struct xfs_fsmap));994 995 /*996 * Grab an empty transaction so that we can use its recursive997 * buffer locking abilities to detect cycles in the rmapbt998 * without deadlocking.999 */1000 error = xfs_trans_alloc_empty(mp, &tp);1001 if (error)1002 break;1003 1004 info.dev = handlers[i].dev;1005 info.last = false;1006 info.pag = NULL;1007 info.low_daddr = XFS_BUF_DADDR_NULL;1008 info.low.rm_blockcount = 0;1009 error = handlers[i].fn(tp, dkeys, &info);1010 if (error)1011 break;1012 xfs_trans_cancel(tp);1013 tp = NULL;1014 info.next_daddr = 0;1015 }1016 1017 if (tp)1018 xfs_trans_cancel(tp);1019 head->fmh_oflags = FMH_OF_DEV_T;1020 return error;1021}1022 1023int1024xfs_ioc_getfsmap(1025 struct xfs_inode *ip,1026 struct fsmap_head __user *arg)1027{1028 struct xfs_fsmap_head xhead = {0};1029 struct fsmap_head head;1030 struct fsmap *recs;1031 unsigned int count;1032 __u32 last_flags = 0;1033 bool done = false;1034 int error;1035 1036 if (copy_from_user(&head, arg, sizeof(struct fsmap_head)))1037 return -EFAULT;1038 if (memchr_inv(head.fmh_reserved, 0, sizeof(head.fmh_reserved)) ||1039 memchr_inv(head.fmh_keys[0].fmr_reserved, 0,1040 sizeof(head.fmh_keys[0].fmr_reserved)) ||1041 memchr_inv(head.fmh_keys[1].fmr_reserved, 0,1042 sizeof(head.fmh_keys[1].fmr_reserved)))1043 return -EINVAL;1044 1045 /*1046 * Use an internal memory buffer so that we don't have to copy fsmap1047 * data to userspace while holding locks. Start by trying to allocate1048 * up to 128k for the buffer, but fall back to a single page if needed.1049 */1050 count = min_t(unsigned int, head.fmh_count,1051 131072 / sizeof(struct fsmap));1052 recs = kvcalloc(count, sizeof(struct fsmap), GFP_KERNEL);1053 if (!recs) {1054 count = min_t(unsigned int, head.fmh_count,1055 PAGE_SIZE / sizeof(struct fsmap));1056 recs = kvcalloc(count, sizeof(struct fsmap), GFP_KERNEL);1057 if (!recs)1058 return -ENOMEM;1059 }1060 1061 xhead.fmh_iflags = head.fmh_iflags;1062 xfs_fsmap_to_internal(&xhead.fmh_keys[0], &head.fmh_keys[0]);1063 xfs_fsmap_to_internal(&xhead.fmh_keys[1], &head.fmh_keys[1]);1064 1065 trace_xfs_getfsmap_low_key(ip->i_mount, &xhead.fmh_keys[0]);1066 trace_xfs_getfsmap_high_key(ip->i_mount, &xhead.fmh_keys[1]);1067 1068 head.fmh_entries = 0;1069 do {1070 struct fsmap __user *user_recs;1071 struct fsmap *last_rec;1072 1073 user_recs = &arg->fmh_recs[head.fmh_entries];1074 xhead.fmh_entries = 0;1075 xhead.fmh_count = min_t(unsigned int, count,1076 head.fmh_count - head.fmh_entries);1077 1078 /* Run query, record how many entries we got. */1079 error = xfs_getfsmap(ip->i_mount, &xhead, recs);1080 switch (error) {1081 case 0:1082 /*1083 * There are no more records in the result set. Copy1084 * whatever we got to userspace and break out.1085 */1086 done = true;1087 break;1088 case -ECANCELED:1089 /*1090 * The internal memory buffer is full. Copy whatever1091 * records we got to userspace and go again if we have1092 * not yet filled the userspace buffer.1093 */1094 error = 0;1095 break;1096 default:1097 goto out_free;1098 }1099 head.fmh_entries += xhead.fmh_entries;1100 head.fmh_oflags = xhead.fmh_oflags;1101 1102 /*1103 * If the caller wanted a record count or there aren't any1104 * new records to return, we're done.1105 */1106 if (head.fmh_count == 0 || xhead.fmh_entries == 0)1107 break;1108 1109 /* Copy all the records we got out to userspace. */1110 if (copy_to_user(user_recs, recs,1111 xhead.fmh_entries * sizeof(struct fsmap))) {1112 error = -EFAULT;1113 goto out_free;1114 }1115 1116 /* Remember the last record flags we copied to userspace. */1117 last_rec = &recs[xhead.fmh_entries - 1];1118 last_flags = last_rec->fmr_flags;1119 1120 /* Set up the low key for the next iteration. */1121 xfs_fsmap_to_internal(&xhead.fmh_keys[0], last_rec);1122 trace_xfs_getfsmap_low_key(ip->i_mount, &xhead.fmh_keys[0]);1123 } while (!done && head.fmh_entries < head.fmh_count);1124 1125 /*1126 * If there are no more records in the query result set and we're not1127 * in counting mode, mark the last record returned with the LAST flag.1128 */1129 if (done && head.fmh_count > 0 && head.fmh_entries > 0) {1130 struct fsmap __user *user_rec;1131 1132 last_flags |= FMR_OF_LAST;1133 user_rec = &arg->fmh_recs[head.fmh_entries - 1];1134 1135 if (copy_to_user(&user_rec->fmr_flags, &last_flags,1136 sizeof(last_flags))) {1137 error = -EFAULT;1138 goto out_free;1139 }1140 }1141 1142 /* copy back header */1143 if (copy_to_user(arg, &head, sizeof(struct fsmap_head))) {1144 error = -EFAULT;1145 goto out_free;1146 }1147 1148out_free:1149 kvfree(recs);1150 return error;1151}1152