Introduce a new ioctl that uses the reverse mapping btree to return information about the physical layout of the filesystem. Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> --- v2: improve comments and refactor common code v3: move the rmap comparator to libxfs and more refactoring --- fs/xfs/Makefile | 1 fs/xfs/libxfs/xfs_fs.h | 13 + fs/xfs/libxfs/xfs_rmap.c | 28 ++ fs/xfs/libxfs/xfs_rmap.h | 2 fs/xfs/xfs_fsmap.c | 772 ++++++++++++++++++++++++++++++++++++++++++++++ fs/xfs/xfs_fsmap.h | 53 +++ fs/xfs/xfs_ioctl.c | 84 +++++ fs/xfs/xfs_ioctl32.c | 2 fs/xfs/xfs_trace.c | 1 fs/xfs/xfs_trace.h | 84 +++++ fs/xfs/xfs_trans.c | 22 + fs/xfs/xfs_trans.h | 2 12 files changed, 1064 insertions(+) create mode 100644 fs/xfs/xfs_fsmap.c create mode 100644 fs/xfs/xfs_fsmap.h diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile index c7515d4..0e7ee30 100644 --- a/fs/xfs/Makefile +++ b/fs/xfs/Makefile @@ -80,6 +80,7 @@ xfs-y += xfs_aops.o \ xfs_extent_busy.o \ xfs_file.o \ xfs_filestream.o \ + xfs_fsmap.o \ xfs_fsops.o \ xfs_globals.o \ xfs_icache.o \ diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h index b72dc82..095bdf0 100644 --- a/fs/xfs/libxfs/xfs_fs.h +++ b/fs/xfs/libxfs/xfs_fs.h @@ -92,6 +92,18 @@ struct getbmapx { #define BMV_OF_LAST 0x4 /* segment is the last in the file */ #define BMV_OF_SHARED 0x8 /* segment shared with another file */ +/* fmr_owner special values for FS_IOC_GETFSMAP */ +#define XFS_FMR_OWN_FREE FMR_OWN_FREE /* free space */ +#define XFS_FMR_OWN_UNKNOWN FMR_OWN_UNKNOWN /* unknown owner */ +#define XFS_FMR_OWN_FS FMR_OWNER('X', 1) /* static fs metadata */ +#define XFS_FMR_OWN_LOG FMR_OWNER('X', 2) /* journalling log */ +#define XFS_FMR_OWN_AG FMR_OWNER('X', 3) /* per-AG metadata */ +#define XFS_FMR_OWN_INOBT FMR_OWNER('X', 4) /* inode btree blocks */ +#define XFS_FMR_OWN_INODES FMR_OWNER('X', 5) /* inodes */ +#define XFS_FMR_OWN_REFC FMR_OWNER('X', 6) /* refcount tree */ +#define XFS_FMR_OWN_COW FMR_OWNER('X', 7) /* cow staging */ +#define XFS_FMR_OWN_DEFECTIVE FMR_OWNER('X', 8) /* bad blocks */ + /* * Structure for XFS_IOC_FSSETDM. * For use by backup and restore programs to set the XFS on-disk inode @@ -502,6 +514,7 @@ typedef struct xfs_swapext #define XFS_IOC_GETBMAPX _IOWR('X', 56, struct getbmap) #define XFS_IOC_ZERO_RANGE _IOW ('X', 57, struct xfs_flock64) #define XFS_IOC_FREE_EOFBLOCKS _IOR ('X', 58, struct xfs_fs_eofblocks) +/* XFS_IOC_GETFSMAP ------ hoisted 59 */ /* * ioctl commands that replace IRIX syssgi()'s diff --git a/fs/xfs/libxfs/xfs_rmap.c b/fs/xfs/libxfs/xfs_rmap.c index 3840556..06cfb93 100644 --- a/fs/xfs/libxfs/xfs_rmap.c +++ b/fs/xfs/libxfs/xfs_rmap.c @@ -2305,3 +2305,31 @@ xfs_rmap_free_extent( return __xfs_rmap_add(mp, dfops, XFS_RMAP_FREE, owner, XFS_DATA_FORK, &bmap); } + +/* Compare rmap records. Returns -1 if a < b, 1 if a > b, and 0 if equal. */ +int +xfs_rmap_compare( + const struct xfs_rmap_irec *a, + const struct xfs_rmap_irec *b) +{ + __u64 oa; + __u64 ob; + + oa = xfs_rmap_irec_offset_pack(a); + ob = xfs_rmap_irec_offset_pack(b); + + if (a->rm_startblock < b->rm_startblock) + return -1; + else if (a->rm_startblock > b->rm_startblock) + return 1; + else if (a->rm_owner < b->rm_owner) + return -1; + else if (a->rm_owner > b->rm_owner) + return 1; + else if (oa < ob) + return -1; + else if (oa > ob) + return 1; + else + return 0; +} diff --git a/fs/xfs/libxfs/xfs_rmap.h b/fs/xfs/libxfs/xfs_rmap.h index faf2c1a..98f908f 100644 --- a/fs/xfs/libxfs/xfs_rmap.h +++ b/fs/xfs/libxfs/xfs_rmap.h @@ -214,5 +214,7 @@ int xfs_rmap_find_left_neighbor(struct xfs_btree_cur *cur, xfs_agblock_t bno, int xfs_rmap_lookup_le_range(struct xfs_btree_cur *cur, xfs_agblock_t bno, uint64_t owner, uint64_t offset, unsigned int flags, struct xfs_rmap_irec *irec, int *stat); +int xfs_rmap_compare(const struct xfs_rmap_irec *a, + const struct xfs_rmap_irec *b); #endif /* __XFS_RMAP_H__ */ diff --git a/fs/xfs/xfs_fsmap.c b/fs/xfs/xfs_fsmap.c new file mode 100644 index 0000000..2fd05a0 --- /dev/null +++ b/fs/xfs/xfs_fsmap.c @@ -0,0 +1,772 @@ +/* + * Copyright (C) 2017 Oracle. All Rights Reserved. + * + * Author: Darrick J. Wong <darrick.wong@xxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it would be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. + */ +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_shared.h" +#include "xfs_format.h" +#include "xfs_log_format.h" +#include "xfs_trans_resv.h" +#include "xfs_sb.h" +#include "xfs_mount.h" +#include "xfs_defer.h" +#include "xfs_inode.h" +#include "xfs_trans.h" +#include "xfs_error.h" +#include "xfs_btree.h" +#include "xfs_rmap_btree.h" +#include "xfs_trace.h" +#include "xfs_log.h" +#include "xfs_rmap.h" +#include "xfs_alloc.h" +#include "xfs_bit.h" +#include <linux/fsmap.h> +#include "xfs_fsmap.h" +#include "xfs_refcount.h" +#include "xfs_refcount_btree.h" + +/* Convert an xfs_fsmap to an fsmap. */ +void +xfs_fsmap_from_internal( + struct fsmap *dest, + struct xfs_fsmap *src) +{ + dest->fmr_device = src->fmr_device; + dest->fmr_flags = src->fmr_flags; + dest->fmr_physical = BBTOB(src->fmr_physical); + dest->fmr_owner = src->fmr_owner; + dest->fmr_offset = BBTOB(src->fmr_offset); + dest->fmr_length = BBTOB(src->fmr_length); + dest->fmr_reserved[0] = 0; + dest->fmr_reserved[1] = 0; + dest->fmr_reserved[2] = 0; +} + +/* Convert an fsmap to an xfs_fsmap. */ +void +xfs_fsmap_to_internal( + struct xfs_fsmap *dest, + struct fsmap *src) +{ + dest->fmr_device = src->fmr_device; + dest->fmr_flags = src->fmr_flags; + dest->fmr_physical = BTOBBT(src->fmr_physical); + dest->fmr_owner = src->fmr_owner; + dest->fmr_offset = BTOBBT(src->fmr_offset); + dest->fmr_length = BTOBBT(src->fmr_length); +} + +/* Convert an fsmap owner into an rmapbt owner. */ +static int +xfs_fsmap_owner_to_rmap( + struct xfs_rmap_irec *dest, + struct xfs_fsmap *src) +{ + if (!(src->fmr_flags & FMR_OF_SPECIAL_OWNER)) { + dest->rm_owner = src->fmr_owner; + return 0; + } + + switch (src->fmr_owner) { + case 0: /* "lowest owner id possible" */ + case -1ULL: /* "highest owner id possible" */ + dest->rm_owner = 0; + break; + case XFS_FMR_OWN_FREE: + dest->rm_owner = XFS_RMAP_OWN_NULL; + break; + case XFS_FMR_OWN_UNKNOWN: + dest->rm_owner = XFS_RMAP_OWN_UNKNOWN; + break; + case XFS_FMR_OWN_FS: + dest->rm_owner = XFS_RMAP_OWN_FS; + break; + case XFS_FMR_OWN_LOG: + dest->rm_owner = XFS_RMAP_OWN_LOG; + break; + case XFS_FMR_OWN_AG: + dest->rm_owner = XFS_RMAP_OWN_AG; + break; + case XFS_FMR_OWN_INOBT: + dest->rm_owner = XFS_RMAP_OWN_INOBT; + break; + case XFS_FMR_OWN_INODES: + dest->rm_owner = XFS_RMAP_OWN_INODES; + break; + case XFS_FMR_OWN_REFC: + dest->rm_owner = XFS_RMAP_OWN_REFC; + break; + case XFS_FMR_OWN_COW: + dest->rm_owner = XFS_RMAP_OWN_COW; + break; + case XFS_FMR_OWN_DEFECTIVE: /* not implemented */ + /* fall through */ + default: + return -EINVAL; + } + return 0; +} + +/* Convert an rmapbt owner into an fsmap owner. */ +static int +xfs_fsmap_owner_from_rmap( + struct xfs_fsmap *dest, + struct xfs_rmap_irec *src) +{ + dest->fmr_flags = 0; + if (!XFS_RMAP_NON_INODE_OWNER(src->rm_owner)) { + dest->fmr_owner = src->rm_owner; + return 0; + } + dest->fmr_flags |= FMR_OF_SPECIAL_OWNER; + + switch (src->rm_owner) { + case XFS_RMAP_OWN_FS: + dest->fmr_owner = XFS_FMR_OWN_FS; + break; + case XFS_RMAP_OWN_LOG: + dest->fmr_owner = XFS_FMR_OWN_LOG; + break; + case XFS_RMAP_OWN_AG: + dest->fmr_owner = XFS_FMR_OWN_AG; + break; + case XFS_RMAP_OWN_INOBT: + dest->fmr_owner = XFS_FMR_OWN_INOBT; + break; + case XFS_RMAP_OWN_INODES: + dest->fmr_owner = XFS_FMR_OWN_INODES; + break; + case XFS_RMAP_OWN_REFC: + dest->fmr_owner = XFS_FMR_OWN_REFC; + break; + case XFS_RMAP_OWN_COW: + dest->fmr_owner = XFS_FMR_OWN_COW; + break; + default: + return -EFSCORRUPTED; + } + return 0; +} + +/* getfsmap query state */ +struct xfs_getfsmap_info { + struct xfs_fsmap_head *head; + xfs_fsmap_format_t formatter; /* formatting fn */ + void *format_arg; /* format buffer */ + struct xfs_buf *agf_bp; /* AGF, for refcount queries */ + xfs_daddr_t next_daddr; /* next daddr we expect */ + u64 missing_owner; /* owner of holes */ + u32 dev; /* device id */ + xfs_agnumber_t agno; /* AG number, if applicable */ + struct xfs_rmap_irec low; /* low rmap key */ + struct xfs_rmap_irec high; /* high rmap key */ + bool last; /* last extent? */ +}; + +/* Associate a device with a getfsmap handler. */ +struct xfs_getfsmap_dev { + u32 dev; + int (*fn)(struct xfs_trans *tp, + struct xfs_fsmap *keys, + struct xfs_getfsmap_info *info); +}; + +/* Compare two getfsmap device handlers. */ +static int +xfs_getfsmap_dev_compare( + const void *p1, + const void *p2) +{ + const struct xfs_getfsmap_dev *d1 = p1; + const struct xfs_getfsmap_dev *d2 = p2; + + return d1->dev - d2->dev; +} + +/* Decide if this mapping is shared. */ +STATIC int +xfs_getfsmap_is_shared( + struct xfs_trans *tp, + struct xfs_getfsmap_info *info, + struct xfs_rmap_irec *rec, + bool *stat) +{ + struct xfs_mount *mp = tp->t_mountp; + struct xfs_btree_cur *cur; + xfs_agblock_t fbno; + xfs_extlen_t flen; + int error; + + *stat = false; + if (!xfs_sb_version_hasreflink(&mp->m_sb)) + return 0; + /* rt files will have agno set to NULLAGNUMBER */ + if (info->agno == NULLAGNUMBER) + return 0; + + /* Are there any shared blocks here? */ + flen = 0; + cur = xfs_refcountbt_init_cursor(mp, tp, info->agf_bp, + info->agno, NULL); + + error = xfs_refcount_find_shared(cur, rec->rm_startblock, + rec->rm_blockcount, &fbno, &flen, false); + + xfs_btree_del_cursor(cur, error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR); + if (error) + return error; + + *stat = flen > 0; + return 0; +} + +/* + * Format a reverse mapping for getfsmap, having translated rm_startblock + * into the appropriate daddr units. + */ +STATIC int +xfs_getfsmap_helper( + struct xfs_trans *tp, + struct xfs_getfsmap_info *info, + struct xfs_rmap_irec *rec, + xfs_daddr_t rec_daddr) +{ + struct xfs_fsmap fmr; + struct xfs_mount *mp = tp->t_mountp; + bool shared; + int error; + + if (fatal_signal_pending(current)) + return -EINTR; + + /* + * Filter out records that start before our startpoint, if the + * caller requested that. + */ + if (xfs_rmap_compare(rec, &info->low) < 0) { + rec_daddr += XFS_FSB_TO_BB(mp, rec->rm_blockcount); + if (info->next_daddr < rec_daddr) + info->next_daddr = rec_daddr; + return XFS_BTREE_QUERY_RANGE_CONTINUE; + } + + /* Are we just counting mappings? */ + if (info->head->fmh_count == 0) { + if (rec_daddr > info->next_daddr) + info->head->fmh_entries++; + + if (info->last) + return XFS_BTREE_QUERY_RANGE_CONTINUE; + + info->head->fmh_entries++; + + rec_daddr += XFS_FSB_TO_BB(mp, rec->rm_blockcount); + if (info->next_daddr < rec_daddr) + info->next_daddr = rec_daddr; + return XFS_BTREE_QUERY_RANGE_CONTINUE; + } + + /* + * If the record starts past the last physical block we saw, + * then we've found a gap. Report the gap as being owned by + * whatever the caller specified is the missing owner. + */ + if (rec_daddr > info->next_daddr) { + if (info->head->fmh_entries >= info->head->fmh_count) + return XFS_BTREE_QUERY_RANGE_ABORT; + + fmr.fmr_device = info->dev; + fmr.fmr_physical = info->next_daddr; + fmr.fmr_owner = info->missing_owner; + fmr.fmr_offset = 0; + fmr.fmr_length = rec_daddr - info->next_daddr; + fmr.fmr_flags = FMR_OF_SPECIAL_OWNER; + error = info->formatter(&fmr, info->format_arg); + if (error) + return error; + info->head->fmh_entries++; + } + + if (info->last) + goto out; + + /* Fill out the extent we found */ + if (info->head->fmh_entries >= info->head->fmh_count) + return XFS_BTREE_QUERY_RANGE_ABORT; + + trace_xfs_fsmap_mapping(mp, info->dev, info->agno, rec); + + fmr.fmr_device = info->dev; + fmr.fmr_physical = rec_daddr; + error = xfs_fsmap_owner_from_rmap(&fmr, rec); + if (error) + return error; + fmr.fmr_offset = XFS_FSB_TO_BB(mp, rec->rm_offset); + fmr.fmr_length = XFS_FSB_TO_BB(mp, rec->rm_blockcount); + if (rec->rm_flags & XFS_RMAP_UNWRITTEN) + fmr.fmr_flags |= FMR_OF_PREALLOC; + if (rec->rm_flags & XFS_RMAP_ATTR_FORK) + fmr.fmr_flags |= FMR_OF_ATTR_FORK; + if (rec->rm_flags & XFS_RMAP_BMBT_BLOCK) + fmr.fmr_flags |= FMR_OF_EXTENT_MAP; + if (fmr.fmr_flags == 0) { + error = xfs_getfsmap_is_shared(tp, info, rec, &shared); + if (error) + return error; + if (shared) + fmr.fmr_flags |= FMR_OF_SHARED; + } + error = info->formatter(&fmr, info->format_arg); + if (error) + return error; + info->head->fmh_entries++; + +out: + rec_daddr += XFS_FSB_TO_BB(mp, rec->rm_blockcount); + if (info->next_daddr < rec_daddr) + info->next_daddr = rec_daddr; + return XFS_BTREE_QUERY_RANGE_CONTINUE; +} + +/* Transform a rmapbt irec into a fsmap */ +STATIC int +xfs_getfsmap_datadev_helper( + struct xfs_btree_cur *cur, + struct xfs_rmap_irec *rec, + void *priv) +{ + struct xfs_mount *mp = cur->bc_mp; + struct xfs_getfsmap_info *info = priv; + xfs_fsblock_t fsb; + xfs_daddr_t rec_daddr; + + fsb = XFS_AGB_TO_FSB(mp, cur->bc_private.a.agno, rec->rm_startblock); + rec_daddr = XFS_FSB_TO_DADDR(mp, fsb); + + return xfs_getfsmap_helper(cur->bc_tp, info, rec, rec_daddr); +} + +/* Transform a absolute-startblock rmap (rtdev, logdev) into a fsmap */ +STATIC int +xfs_getfsmap_rtdev_helper( + struct xfs_btree_cur *cur, + struct xfs_rmap_irec *rec, + void *priv) +{ + struct xfs_mount *mp = cur->bc_mp; + struct xfs_getfsmap_info *info = priv; + xfs_daddr_t rec_daddr; + + rec_daddr = XFS_FSB_TO_BB(mp, rec->rm_startblock); + + return xfs_getfsmap_helper(cur->bc_tp, info, rec, rec_daddr); +} + +/* Set rmap flags based on the getfsmap flags */ +static void +xfs_getfsmap_set_irec_flags( + struct xfs_rmap_irec *irec, + struct xfs_fsmap *fmr) +{ + irec->rm_flags = 0; + if (fmr->fmr_flags & FMR_OF_ATTR_FORK) + irec->rm_flags |= XFS_RMAP_ATTR_FORK; + if (fmr->fmr_flags & FMR_OF_EXTENT_MAP) + irec->rm_flags |= XFS_RMAP_BMBT_BLOCK; + if (fmr->fmr_flags & FMR_OF_PREALLOC) + irec->rm_flags |= XFS_RMAP_UNWRITTEN; +} + +/* Execute a getfsmap query against the log device. */ +STATIC int +xfs_getfsmap_logdev( + struct xfs_trans *tp, + struct xfs_fsmap *keys, + struct xfs_getfsmap_info *info) +{ + struct xfs_mount *mp = tp->t_mountp; + struct xfs_rmap_irec rmap; + int error; + + /* Set up search keys */ + info->low.rm_startblock = XFS_BB_TO_FSBT(mp, keys[0].fmr_physical); + info->low.rm_offset = XFS_BB_TO_FSBT(mp, keys[0].fmr_offset); + error = xfs_fsmap_owner_to_rmap(&info->low, keys); + if (error) + return error; + info->low.rm_blockcount = 0; + xfs_getfsmap_set_irec_flags(&info->low, &keys[0]); + + error = xfs_fsmap_owner_to_rmap(&info->high, keys + 1); + if (error) + return error; + info->high.rm_startblock = -1U; + info->high.rm_owner = ULLONG_MAX; + info->high.rm_offset = ULLONG_MAX; + info->high.rm_blockcount = 0; + info->high.rm_flags = XFS_RMAP_KEY_FLAGS | XFS_RMAP_REC_FLAGS; + info->missing_owner = XFS_FMR_OWN_FREE; + + trace_xfs_fsmap_low_key(mp, info->dev, info->agno, &info->low); + trace_xfs_fsmap_high_key(mp, info->dev, info->agno, &info->high); + + if (keys[0].fmr_physical > 0) + return 0; + + /* Fabricate an rmap entry for the external log device. */ + rmap.rm_startblock = 0; + rmap.rm_blockcount = mp->m_sb.sb_logblocks; + rmap.rm_owner = XFS_RMAP_OWN_LOG; + rmap.rm_offset = 0; + rmap.rm_flags = 0; + + return xfs_getfsmap_helper(tp, info, &rmap, 0); +} + +/* Execute a getfsmap query against the regular data device. */ +STATIC int +__xfs_getfsmap_datadev( + struct xfs_trans *tp, + struct xfs_fsmap *keys, + struct xfs_getfsmap_info *info, + int (*query_fn)(struct xfs_trans *, + struct xfs_getfsmap_info *, + struct xfs_btree_cur **, + void *), + void *priv) +{ + struct xfs_mount *mp = tp->t_mountp; + struct xfs_btree_cur *bt_cur = NULL; + xfs_fsblock_t start_fsb; + xfs_fsblock_t end_fsb; + xfs_agnumber_t start_ag; + xfs_agnumber_t end_ag; + xfs_daddr_t eofs; + int error = 0; + + eofs = XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks); + if (keys[0].fmr_physical >= eofs) + return 0; + if (keys[1].fmr_physical >= eofs) + keys[1].fmr_physical = eofs - 1; + start_fsb = XFS_DADDR_TO_FSB(mp, keys[0].fmr_physical); + end_fsb = XFS_DADDR_TO_FSB(mp, keys[1].fmr_physical); + + /* + * Convert the fsmap low/high keys to AG based keys. Initialize + * low to the fsmap low key and max out the high key to the end + * of the AG. + */ + info->low.rm_startblock = XFS_FSB_TO_AGBNO(mp, start_fsb); + info->low.rm_offset = XFS_BB_TO_FSBT(mp, keys[0].fmr_offset); + error = xfs_fsmap_owner_to_rmap(&info->low, &keys[0]); + if (error) + return error; + info->low.rm_blockcount = 0; + xfs_getfsmap_set_irec_flags(&info->low, &keys[0]); + + info->high.rm_startblock = -1U; + info->high.rm_owner = ULLONG_MAX; + info->high.rm_offset = ULLONG_MAX; + info->high.rm_blockcount = 0; + info->high.rm_flags = XFS_RMAP_KEY_FLAGS | XFS_RMAP_REC_FLAGS; + + start_ag = XFS_FSB_TO_AGNO(mp, start_fsb); + end_ag = XFS_FSB_TO_AGNO(mp, end_fsb); + + /* Query each AG */ + for (info->agno = start_ag; info->agno <= end_ag; info->agno++) { + /* + * Set the AG high key from the fsmap high key if this + * is the last AG that we're querying. + */ + if (info->agno == end_ag) { + info->high.rm_startblock = XFS_FSB_TO_AGBNO(mp, + end_fsb); + info->high.rm_offset = XFS_BB_TO_FSBT(mp, + keys[1].fmr_offset); + error = xfs_fsmap_owner_to_rmap(&info->high, &keys[1]); + if (error) + goto err; + xfs_getfsmap_set_irec_flags(&info->high, &keys[1]); + } + + if (bt_cur) { + xfs_btree_del_cursor(bt_cur, XFS_BTREE_NOERROR); + bt_cur = NULL; + xfs_trans_brelse(tp, info->agf_bp); + info->agf_bp = NULL; + } + + error = xfs_alloc_read_agf(mp, tp, info->agno, 0, + &info->agf_bp); + if (error) + goto err; + + trace_xfs_fsmap_low_key(mp, info->dev, info->agno, &info->low); + trace_xfs_fsmap_high_key(mp, info->dev, info->agno, + &info->high); + + error = query_fn(tp, info, &bt_cur, priv); + if (error) + goto err; + + /* + * Set the AG low key to the start of the AG prior to + * moving on to the next AG. + */ + if (info->agno == start_ag) { + info->low.rm_startblock = 0; + info->low.rm_owner = 0; + info->low.rm_offset = 0; + info->low.rm_flags = 0; + } + } + + /* Report any gap at the end of the AG */ + info->last = true; + error = query_fn(tp, info, &bt_cur, priv); + if (error) + goto err; + +err: + if (bt_cur) + xfs_btree_del_cursor(bt_cur, error < 0 ? XFS_BTREE_ERROR : + XFS_BTREE_NOERROR); + if (info->agf_bp) { + xfs_trans_brelse(tp, info->agf_bp); + info->agf_bp = NULL; + } + + return error; +} + +/* Actually query the rmap btree. */ +STATIC int +xfs_getfsmap_datadev_rmapbt_query( + struct xfs_trans *tp, + struct xfs_getfsmap_info *info, + struct xfs_btree_cur **curpp, + void *priv) +{ + /* Report any gap at the end of the last AG. */ + if (info->last) + return xfs_getfsmap_datadev_helper(*curpp, &info->high, info); + + /* Allocate cursor for this AG and query_range it. */ + *curpp = xfs_rmapbt_init_cursor(tp->t_mountp, tp, info->agf_bp, + info->agno); + return xfs_rmap_query_range(*curpp, &info->low, &info->high, + xfs_getfsmap_datadev_helper, info); +} + +/* Execute a getfsmap query against the regular data device rmapbt. */ +STATIC int +xfs_getfsmap_datadev_rmapbt( + struct xfs_trans *tp, + struct xfs_fsmap *keys, + struct xfs_getfsmap_info *info) +{ + info->missing_owner = XFS_FMR_OWN_FREE; + return __xfs_getfsmap_datadev(tp, keys, info, + xfs_getfsmap_datadev_rmapbt_query, NULL); +} + +/* Do we recognize the device? */ +STATIC bool +xfs_getfsmap_is_valid_device( + struct xfs_mount *mp, + struct xfs_fsmap *fm) +{ + if (fm->fmr_device == 0 || fm->fmr_device == UINT_MAX || + fm->fmr_device == new_encode_dev(mp->m_ddev_targp->bt_dev)) + return true; + if (mp->m_logdev_targp && + fm->fmr_device == new_encode_dev(mp->m_logdev_targp->bt_dev)) + return true; + return false; +} + +/* Ensure that the low key is less than the high key. */ +STATIC bool +xfs_getfsmap_check_keys( + struct xfs_fsmap *low_key, + struct xfs_fsmap *high_key) +{ + if (low_key->fmr_device > high_key->fmr_device) + return false; + if (low_key->fmr_device < high_key->fmr_device) + return true; + + if (low_key->fmr_physical > high_key->fmr_physical) + return false; + if (low_key->fmr_physical < high_key->fmr_physical) + return true; + + if (low_key->fmr_owner > high_key->fmr_owner) + return false; + if (low_key->fmr_owner < high_key->fmr_owner) + return true; + + if (low_key->fmr_offset > high_key->fmr_offset) + return false; + if (low_key->fmr_offset < high_key->fmr_offset) + return true; + + return false; +} + +#define XFS_GETFSMAP_DEVS 2 +/* + * Get filesystem's extents as described in head, and format for + * output. Calls formatter to fill the user's buffer until all + * extents are mapped, until the passed-in head->fmh_count slots have + * been filled, or until the formatter short-circuits the loop, if it + * is tracking filled-in extents on its own. + * + * Key to Confusion + * ---------------- + * There are multiple levels of keys and counters at work here: + * xfs_fsmap_head.fmh_keys -- low and high fsmap keys passed in; + * these reflect fs-wide sector addrs. + * dkeys -- fmh_keys used to query each device; + * these are fmh_keys but w/ the low key + * bumped up by fmr_length. + * xfs_getfsmap_info.next_daddr -- next disk addr we expect to see; this + * is how we detect gaps in the fsmap + records and report them. + * xfs_getfsmap_info.low/high -- per-AG low/high keys computed from + * dkeys; used to query the metadata. + */ +int +xfs_getfsmap( + struct xfs_mount *mp, + struct xfs_fsmap_head *head, + xfs_fsmap_format_t formatter, + void *arg) +{ + struct xfs_trans *tp = NULL; + struct xfs_fsmap dkeys[2]; /* per-dev keys */ + struct xfs_getfsmap_dev handlers[XFS_GETFSMAP_DEVS]; + struct xfs_getfsmap_info info = {0}; + int i; + int error = 0; + + if (!xfs_sb_version_hasrmapbt(&mp->m_sb)) + return -EOPNOTSUPP; + if (head->fmh_iflags & ~FMH_IF_VALID) + return -EINVAL; + if (!xfs_getfsmap_is_valid_device(mp, &head->fmh_keys[0]) || + !xfs_getfsmap_is_valid_device(mp, &head->fmh_keys[1])) + return -EINVAL; + + head->fmh_entries = 0; + + /* Set up our device handlers. */ + memset(handlers, 0, sizeof(handlers)); + handlers[0].dev = new_encode_dev(mp->m_ddev_targp->bt_dev); + handlers[0].fn = xfs_getfsmap_datadev_rmapbt; + if (mp->m_logdev_targp != mp->m_ddev_targp) { + handlers[1].dev = new_encode_dev(mp->m_logdev_targp->bt_dev); + handlers[1].fn = xfs_getfsmap_logdev; + } + + xfs_sort(handlers, XFS_GETFSMAP_DEVS, sizeof(struct xfs_getfsmap_dev), + xfs_getfsmap_dev_compare); + + /* + * To continue where we left off, we allow userspace to use the + * last mapping from a previous call as the low key of the next. + * This is identified by a non-zero length in the low key. We + * have to increment the low key in this scenario to ensure we + * don't return the same mapping again, and instead return the + * very next mapping. + * + * If the low key mapping refers to file data, the same physical + * blocks could be mapped to several other files/offsets. + * According to rmapbt record ordering, the minimal next + * possible record for the block range is the next starting + * offset in the same inode. Therefore, bump the file offset to + * continue the search appropriately. For all other low key + * mapping types (attr blocks, metadata), bump the physical + * offset as there can be no other mapping for the same physical + * block range. + */ + dkeys[0] = head->fmh_keys[0]; + if (dkeys[0].fmr_flags & (FMR_OF_SPECIAL_OWNER | FMR_OF_EXTENT_MAP)) { + dkeys[0].fmr_physical += dkeys[0].fmr_length; + dkeys[0].fmr_owner = 0; + if (dkeys[0].fmr_offset) + return -EINVAL; + } else + dkeys[0].fmr_offset += dkeys[0].fmr_length; + dkeys[0].fmr_length = 0; + memset(&dkeys[1], 0xFF, sizeof(struct xfs_fsmap)); + + if (!xfs_getfsmap_check_keys(dkeys, &head->fmh_keys[1])) + return -EINVAL; + + info.next_daddr = head->fmh_keys[0].fmr_physical + + head->fmh_keys[0].fmr_length; + info.formatter = formatter; + info.format_arg = arg; + info.head = head; + + /* For each device we support... */ + for (i = 0; i < XFS_GETFSMAP_DEVS; i++) { + /* Is this device within the range the user asked for? */ + if (!handlers[i].fn) + continue; + if (head->fmh_keys[0].fmr_device > handlers[i].dev) + continue; + if (head->fmh_keys[1].fmr_device < handlers[i].dev) + break; + + /* + * If this device number matches the high key, we have + * to pass the high key to the handler to limit the + * query results. If the device number exceeds the + * low key, zero out the low key so that we get + * everything from the beginning. + */ + if (handlers[i].dev == head->fmh_keys[1].fmr_device) + dkeys[1] = head->fmh_keys[1]; + if (handlers[i].dev > head->fmh_keys[0].fmr_device) + memset(&dkeys[0], 0, sizeof(struct xfs_fsmap)); + + error = xfs_trans_alloc_empty(mp, &tp); + if (error) + break; + + info.dev = handlers[i].dev; + info.last = false; + info.agno = NULLAGNUMBER; + error = handlers[i].fn(tp, dkeys, &info); + if (error) + break; + xfs_trans_cancel(tp); + tp = NULL; + info.next_daddr = 0; + } + + if (tp) + xfs_trans_cancel(tp); + head->fmh_oflags = FMH_OF_DEV_T; + return error; +} diff --git a/fs/xfs/xfs_fsmap.h b/fs/xfs/xfs_fsmap.h new file mode 100644 index 0000000..0b9bf82 --- /dev/null +++ b/fs/xfs/xfs_fsmap.h @@ -0,0 +1,53 @@ +/* + * Copyright (C) 2017 Oracle. All Rights Reserved. + * + * Author: Darrick J. Wong <darrick.wong@xxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it would be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. + */ +#ifndef __XFS_FSMAP_H__ +#define __XFS_FSMAP_H__ + +struct fsmap; + +/* internal fsmap representation */ +struct xfs_fsmap { + dev_t fmr_device; /* device id */ + uint32_t fmr_flags; /* mapping flags */ + uint64_t fmr_physical; /* device offset of segment */ + uint64_t fmr_owner; /* owner id */ + xfs_fileoff_t fmr_offset; /* file offset of segment */ + xfs_filblks_t fmr_length; /* length of segment, blocks */ +}; + +struct xfs_fsmap_head { + uint32_t fmh_iflags; /* control flags */ + uint32_t fmh_oflags; /* output flags */ + unsigned int fmh_count; /* # of entries in array incl. input */ + unsigned int fmh_entries; /* # of entries filled in (output). */ + + struct xfs_fsmap fmh_keys[2]; /* low and high keys */ +}; + +void xfs_fsmap_from_internal(struct fsmap *dest, struct xfs_fsmap *src); +void xfs_fsmap_to_internal(struct xfs_fsmap *dest, struct fsmap *src); + +/* fsmap to userspace formatter - copy to user & advance pointer */ +typedef int (*xfs_fsmap_format_t)(struct xfs_fsmap *, void *); + +int xfs_getfsmap(struct xfs_mount *mp, struct xfs_fsmap_head *head, + xfs_fsmap_format_t formatter, void *arg); + +#endif /* __XFS_FSMAP_H__ */ diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index c67cfb4..52f635a 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -41,6 +41,9 @@ #include "xfs_trans.h" #include "xfs_pnfs.h" #include "xfs_acl.h" +#include "xfs_btree.h" +#include <linux/fsmap.h> +#include "xfs_fsmap.h" #include <linux/capability.h> #include <linux/dcache.h> @@ -1607,6 +1610,84 @@ xfs_ioc_getbmapx( return 0; } +struct getfsmap_info { + struct xfs_mount *mp; + struct fsmap __user *data; + __u32 last_flags; +}; + +STATIC int +xfs_getfsmap_format(struct xfs_fsmap *xfm, void *priv) +{ + struct getfsmap_info *info = priv; + struct fsmap fm; + + trace_xfs_getfsmap_mapping(info->mp, xfm); + + info->last_flags = xfm->fmr_flags; + xfs_fsmap_from_internal(&fm, xfm); + if (copy_to_user(info->data, &fm, sizeof(struct fsmap))) + return -EFAULT; + + info->data++; + return 0; +} + +STATIC int +xfs_ioc_getfsmap( + struct xfs_inode *ip, + void __user *arg) +{ + struct getfsmap_info info; + struct xfs_fsmap_head xhead = {0}; + struct fsmap_head head; + bool aborted = false; + int error; + + if (copy_from_user(&head, arg, sizeof(struct fsmap_head))) + return -EFAULT; + if (memchr_inv(head.fmh_reserved, 0, sizeof(head.fmh_reserved)) || + memchr_inv(head.fmh_keys[0].fmr_reserved, 0, + sizeof(head.fmh_keys[0].fmr_reserved)) || + memchr_inv(head.fmh_keys[1].fmr_reserved, 0, + sizeof(head.fmh_keys[1].fmr_reserved))) + return -EINVAL; + + xhead.fmh_iflags = head.fmh_iflags; + xhead.fmh_count = head.fmh_count; + xfs_fsmap_to_internal(&xhead.fmh_keys[0], &head.fmh_keys[0]); + xfs_fsmap_to_internal(&xhead.fmh_keys[1], &head.fmh_keys[1]); + + trace_xfs_getfsmap_low_key(ip->i_mount, &xhead.fmh_keys[0]); + trace_xfs_getfsmap_high_key(ip->i_mount, &xhead.fmh_keys[1]); + + info.mp = ip->i_mount; + info.data = ((__force struct fsmap_head *)arg)->fmh_recs; + error = xfs_getfsmap(ip->i_mount, &xhead, xfs_getfsmap_format, &info); + if (error == XFS_BTREE_QUERY_RANGE_ABORT) { + error = 0; + aborted = true; + } else if (error) + return error; + + /* If we didn't abort, set the "last" flag in the last fmx */ + if (!aborted && xhead.fmh_entries) { + info.data--; + info.last_flags |= FMR_OF_LAST; + if (copy_to_user(&info.data->fmr_flags, &info.last_flags, + sizeof(info.last_flags))) + return -EFAULT; + } + + /* copy back header */ + head.fmh_entries = xhead.fmh_entries; + head.fmh_oflags = xhead.fmh_oflags; + if (copy_to_user(arg, &head, sizeof(struct fsmap_head))) + return -EFAULT; + + return 0; +} + int xfs_ioc_swapext( xfs_swapext_t *sxp) @@ -1787,6 +1868,9 @@ xfs_file_ioctl( case XFS_IOC_GETBMAPX: return xfs_ioc_getbmapx(ip, arg); + case FS_IOC_GETFSMAP: + return xfs_ioc_getfsmap(ip, arg); + case XFS_IOC_FD_TO_HANDLE: case XFS_IOC_PATH_TO_HANDLE: case XFS_IOC_PATH_TO_FSHANDLE: { diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c index 7c49938..fa0bc4d 100644 --- a/fs/xfs/xfs_ioctl32.c +++ b/fs/xfs/xfs_ioctl32.c @@ -20,6 +20,7 @@ #include <linux/mount.h> #include <linux/slab.h> #include <linux/uaccess.h> +#include <linux/fsmap.h> #include "xfs.h" #include "xfs_fs.h" #include "xfs_format.h" @@ -554,6 +555,7 @@ xfs_file_compat_ioctl( case XFS_IOC_GOINGDOWN: case XFS_IOC_ERROR_INJECTION: case XFS_IOC_ERROR_CLEARALL: + case FS_IOC_GETFSMAP: return xfs_file_ioctl(filp, cmd, p); #ifndef BROKEN_X86_ALIGNMENT /* These are handled fine if no alignment issues */ diff --git a/fs/xfs/xfs_trace.c b/fs/xfs/xfs_trace.c index 7f17ae6..5d95fe3 100644 --- a/fs/xfs/xfs_trace.c +++ b/fs/xfs/xfs_trace.c @@ -47,6 +47,7 @@ #include "xfs_inode_item.h" #include "xfs_bmap_btree.h" #include "xfs_filestream.h" +#include "xfs_fsmap.h" /* * We include this last to have the helpers above available for the trace diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index d3d11905..ef666e6 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -40,6 +40,8 @@ struct xfs_inode_log_format; struct xfs_bmbt_irec; struct xfs_btree_cur; struct xfs_refcount_irec; +struct xfs_fsmap; +struct xfs_rmap_irec; DECLARE_EVENT_CLASS(xfs_attr_list_class, TP_PROTO(struct xfs_attr_list_context *ctx), @@ -3270,6 +3272,88 @@ DEFINE_INODE_IREC_EVENT(xfs_swap_extent_rmap_remap); DEFINE_INODE_IREC_EVENT(xfs_swap_extent_rmap_remap_piece); DEFINE_INODE_ERROR_EVENT(xfs_swap_extent_rmap_error); +/* fsmap traces */ +DECLARE_EVENT_CLASS(xfs_fsmap_class, + TP_PROTO(struct xfs_mount *mp, u32 keydev, xfs_agnumber_t agno, + struct xfs_rmap_irec *rmap), + TP_ARGS(mp, keydev, agno, rmap), + TP_STRUCT__entry( + __field(dev_t, dev) + __field(dev_t, keydev) + __field(xfs_agnumber_t, agno) + __field(xfs_fsblock_t, bno) + __field(xfs_filblks_t, len) + __field(__uint64_t, owner) + __field(__uint64_t, offset) + __field(unsigned int, flags) + ), + TP_fast_assign( + __entry->dev = mp->m_super->s_dev; + __entry->keydev = new_decode_dev(keydev); + __entry->agno = agno; + __entry->bno = rmap->rm_startblock; + __entry->len = rmap->rm_blockcount; + __entry->owner = rmap->rm_owner; + __entry->offset = rmap->rm_offset; + __entry->flags = rmap->rm_flags; + ), + TP_printk("dev %d:%d keydev %d:%d agno %u bno %llu len %llu owner %lld offset %llu flags 0x%x\n", + MAJOR(__entry->dev), MINOR(__entry->dev), + MAJOR(__entry->keydev), MINOR(__entry->keydev), + __entry->agno, + __entry->bno, + __entry->len, + __entry->owner, + __entry->offset, + __entry->flags) +) +#define DEFINE_FSMAP_EVENT(name) \ +DEFINE_EVENT(xfs_fsmap_class, name, \ + TP_PROTO(struct xfs_mount *mp, u32 keydev, xfs_agnumber_t agno, \ + struct xfs_rmap_irec *rmap), \ + TP_ARGS(mp, keydev, agno, rmap)) +DEFINE_FSMAP_EVENT(xfs_fsmap_low_key); +DEFINE_FSMAP_EVENT(xfs_fsmap_high_key); +DEFINE_FSMAP_EVENT(xfs_fsmap_mapping); + +DECLARE_EVENT_CLASS(xfs_getfsmap_class, + TP_PROTO(struct xfs_mount *mp, struct xfs_fsmap *fsmap), + TP_ARGS(mp, fsmap), + TP_STRUCT__entry( + __field(dev_t, dev) + __field(dev_t, keydev) + __field(xfs_daddr_t, block) + __field(xfs_daddr_t, len) + __field(__uint64_t, owner) + __field(__uint64_t, offset) + __field(__uint64_t, flags) + ), + TP_fast_assign( + __entry->dev = mp->m_super->s_dev; + __entry->keydev = new_decode_dev(fsmap->fmr_device); + __entry->block = fsmap->fmr_physical; + __entry->len = fsmap->fmr_length; + __entry->owner = fsmap->fmr_owner; + __entry->offset = fsmap->fmr_offset; + __entry->flags = fsmap->fmr_flags; + ), + TP_printk("dev %d:%d keydev %d:%d block %llu len %llu owner %lld offset %llu flags 0x%llx\n", + MAJOR(__entry->dev), MINOR(__entry->dev), + MAJOR(__entry->keydev), MINOR(__entry->keydev), + __entry->block, + __entry->len, + __entry->owner, + __entry->offset, + __entry->flags) +) +#define DEFINE_GETFSMAP_EVENT(name) \ +DEFINE_EVENT(xfs_getfsmap_class, name, \ + TP_PROTO(struct xfs_mount *mp, struct xfs_fsmap *fsmap), \ + TP_ARGS(mp, fsmap)) +DEFINE_GETFSMAP_EVENT(xfs_getfsmap_low_key); +DEFINE_GETFSMAP_EVENT(xfs_getfsmap_high_key); +DEFINE_GETFSMAP_EVENT(xfs_getfsmap_mapping); + #endif /* _TRACE_XFS_H */ #undef TRACE_INCLUDE_PATH diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c index 70f42ea..a280e12 100644 --- a/fs/xfs/xfs_trans.c +++ b/fs/xfs/xfs_trans.c @@ -263,6 +263,28 @@ xfs_trans_alloc( } /* + * Create an empty transaction with no reservation. This is a defensive + * mechanism for routines that query metadata without actually modifying + * them -- if the metadata being queried is somehow cross-linked (think a + * btree block pointer that points higher in the tree), we risk deadlock. + * However, blocks grabbed as part of a transaction can be re-grabbed. + * The verifiers will notice the corrupt block and the operation will fail + * back to userspace without deadlocking. + * + * Note the zero-length reservation; this transaction MUST be cancelled + * without any dirty data. + */ +int +xfs_trans_alloc_empty( + struct xfs_mount *mp, + struct xfs_trans **tpp) +{ + struct xfs_trans_res resv = {0}; + + return xfs_trans_alloc(mp, &resv, 0, 0, XFS_TRANS_NO_WRITECOUNT, tpp); +} + +/* * Record the indicated change to the given field for application * to the file system's superblock when the transaction commits. * For now, just store the change in the transaction structure. diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h index 61b7fbd..98024cb 100644 --- a/fs/xfs/xfs_trans.h +++ b/fs/xfs/xfs_trans.h @@ -159,6 +159,8 @@ typedef struct xfs_trans { int xfs_trans_alloc(struct xfs_mount *mp, struct xfs_trans_res *resp, uint blocks, uint rtextents, uint flags, struct xfs_trans **tpp); +int xfs_trans_alloc_empty(struct xfs_mount *mp, + struct xfs_trans **tpp); void xfs_trans_mod_sb(xfs_trans_t *, uint, int64_t); struct xfs_buf *xfs_trans_get_buf_map(struct xfs_trans *tp,