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xfs_rmap.c
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xfs_rmap.c
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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2014 Red Hat, Inc.
* All Rights Reserved.
*/
#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_bit.h"
#include "xfs_mount.h"
#include "xfs_sb.h"
#include "xfs_defer.h"
#include "xfs_btree.h"
#include "xfs_trans.h"
#include "xfs_alloc.h"
#include "xfs_rmap.h"
#include "xfs_rmap_btree.h"
#include "xfs_trace.h"
#include "xfs_errortag.h"
#include "xfs_error.h"
#include "xfs_inode.h"
#include "xfs_ag.h"
/*
* Lookup the first record less than or equal to [bno, len, owner, offset]
* in the btree given by cur.
*/
int
xfs_rmap_lookup_le(
struct xfs_btree_cur *cur,
xfs_agblock_t bno,
xfs_extlen_t len,
uint64_t owner,
uint64_t offset,
unsigned int flags,
int *stat)
{
cur->bc_rec.r.rm_startblock = bno;
cur->bc_rec.r.rm_blockcount = len;
cur->bc_rec.r.rm_owner = owner;
cur->bc_rec.r.rm_offset = offset;
cur->bc_rec.r.rm_flags = flags;
return xfs_btree_lookup(cur, XFS_LOOKUP_LE, stat);
}
/*
* Lookup the record exactly matching [bno, len, owner, offset]
* in the btree given by cur.
*/
int
xfs_rmap_lookup_eq(
struct xfs_btree_cur *cur,
xfs_agblock_t bno,
xfs_extlen_t len,
uint64_t owner,
uint64_t offset,
unsigned int flags,
int *stat)
{
cur->bc_rec.r.rm_startblock = bno;
cur->bc_rec.r.rm_blockcount = len;
cur->bc_rec.r.rm_owner = owner;
cur->bc_rec.r.rm_offset = offset;
cur->bc_rec.r.rm_flags = flags;
return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, stat);
}
/*
* Update the record referred to by cur to the value given
* by [bno, len, owner, offset].
* This either works (return 0) or gets an EFSCORRUPTED error.
*/
STATIC int
xfs_rmap_update(
struct xfs_btree_cur *cur,
struct xfs_rmap_irec *irec)
{
union xfs_btree_rec rec;
int error;
trace_xfs_rmap_update(cur->bc_mp, cur->bc_ag.pag->pag_agno,
irec->rm_startblock, irec->rm_blockcount,
irec->rm_owner, irec->rm_offset, irec->rm_flags);
rec.rmap.rm_startblock = cpu_to_be32(irec->rm_startblock);
rec.rmap.rm_blockcount = cpu_to_be32(irec->rm_blockcount);
rec.rmap.rm_owner = cpu_to_be64(irec->rm_owner);
rec.rmap.rm_offset = cpu_to_be64(
xfs_rmap_irec_offset_pack(irec));
error = xfs_btree_update(cur, &rec);
if (error)
trace_xfs_rmap_update_error(cur->bc_mp,
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
return error;
}
int
xfs_rmap_insert(
struct xfs_btree_cur *rcur,
xfs_agblock_t agbno,
xfs_extlen_t len,
uint64_t owner,
uint64_t offset,
unsigned int flags)
{
int i;
int error;
trace_xfs_rmap_insert(rcur->bc_mp, rcur->bc_ag.pag->pag_agno, agbno,
len, owner, offset, flags);
error = xfs_rmap_lookup_eq(rcur, agbno, len, owner, offset, flags, &i);
if (error)
goto done;
if (XFS_IS_CORRUPT(rcur->bc_mp, i != 0)) {
error = -EFSCORRUPTED;
goto done;
}
rcur->bc_rec.r.rm_startblock = agbno;
rcur->bc_rec.r.rm_blockcount = len;
rcur->bc_rec.r.rm_owner = owner;
rcur->bc_rec.r.rm_offset = offset;
rcur->bc_rec.r.rm_flags = flags;
error = xfs_btree_insert(rcur, &i);
if (error)
goto done;
if (XFS_IS_CORRUPT(rcur->bc_mp, i != 1)) {
error = -EFSCORRUPTED;
goto done;
}
done:
if (error)
trace_xfs_rmap_insert_error(rcur->bc_mp,
rcur->bc_ag.pag->pag_agno, error, _RET_IP_);
return error;
}
STATIC int
xfs_rmap_delete(
struct xfs_btree_cur *rcur,
xfs_agblock_t agbno,
xfs_extlen_t len,
uint64_t owner,
uint64_t offset,
unsigned int flags)
{
int i;
int error;
trace_xfs_rmap_delete(rcur->bc_mp, rcur->bc_ag.pag->pag_agno, agbno,
len, owner, offset, flags);
error = xfs_rmap_lookup_eq(rcur, agbno, len, owner, offset, flags, &i);
if (error)
goto done;
if (XFS_IS_CORRUPT(rcur->bc_mp, i != 1)) {
error = -EFSCORRUPTED;
goto done;
}
error = xfs_btree_delete(rcur, &i);
if (error)
goto done;
if (XFS_IS_CORRUPT(rcur->bc_mp, i != 1)) {
error = -EFSCORRUPTED;
goto done;
}
done:
if (error)
trace_xfs_rmap_delete_error(rcur->bc_mp,
rcur->bc_ag.pag->pag_agno, error, _RET_IP_);
return error;
}
/* Convert an internal btree record to an rmap record. */
int
xfs_rmap_btrec_to_irec(
const union xfs_btree_rec *rec,
struct xfs_rmap_irec *irec)
{
irec->rm_startblock = be32_to_cpu(rec->rmap.rm_startblock);
irec->rm_blockcount = be32_to_cpu(rec->rmap.rm_blockcount);
irec->rm_owner = be64_to_cpu(rec->rmap.rm_owner);
return xfs_rmap_irec_offset_unpack(be64_to_cpu(rec->rmap.rm_offset),
irec);
}
/*
* Get the data from the pointed-to record.
*/
int
xfs_rmap_get_rec(
struct xfs_btree_cur *cur,
struct xfs_rmap_irec *irec,
int *stat)
{
struct xfs_mount *mp = cur->bc_mp;
xfs_agnumber_t agno = cur->bc_ag.pag->pag_agno;
union xfs_btree_rec *rec;
int error;
error = xfs_btree_get_rec(cur, &rec, stat);
if (error || !*stat)
return error;
if (xfs_rmap_btrec_to_irec(rec, irec))
goto out_bad_rec;
if (irec->rm_blockcount == 0)
goto out_bad_rec;
if (irec->rm_startblock <= XFS_AGFL_BLOCK(mp)) {
if (irec->rm_owner != XFS_RMAP_OWN_FS)
goto out_bad_rec;
if (irec->rm_blockcount != XFS_AGFL_BLOCK(mp) + 1)
goto out_bad_rec;
} else {
/* check for valid extent range, including overflow */
if (!xfs_verify_agbno(mp, agno, irec->rm_startblock))
goto out_bad_rec;
if (irec->rm_startblock >
irec->rm_startblock + irec->rm_blockcount)
goto out_bad_rec;
if (!xfs_verify_agbno(mp, agno,
irec->rm_startblock + irec->rm_blockcount - 1))
goto out_bad_rec;
}
if (!(xfs_verify_ino(mp, irec->rm_owner) ||
(irec->rm_owner <= XFS_RMAP_OWN_FS &&
irec->rm_owner >= XFS_RMAP_OWN_MIN)))
goto out_bad_rec;
return 0;
out_bad_rec:
xfs_warn(mp,
"Reverse Mapping BTree record corruption in AG %d detected!",
agno);
xfs_warn(mp,
"Owner 0x%llx, flags 0x%x, start block 0x%x block count 0x%x",
irec->rm_owner, irec->rm_flags, irec->rm_startblock,
irec->rm_blockcount);
return -EFSCORRUPTED;
}
struct xfs_find_left_neighbor_info {
struct xfs_rmap_irec high;
struct xfs_rmap_irec *irec;
int *stat;
};
/* For each rmap given, figure out if it matches the key we want. */
STATIC int
xfs_rmap_find_left_neighbor_helper(
struct xfs_btree_cur *cur,
const struct xfs_rmap_irec *rec,
void *priv)
{
struct xfs_find_left_neighbor_info *info = priv;
trace_xfs_rmap_find_left_neighbor_candidate(cur->bc_mp,
cur->bc_ag.pag->pag_agno, rec->rm_startblock,
rec->rm_blockcount, rec->rm_owner, rec->rm_offset,
rec->rm_flags);
if (rec->rm_owner != info->high.rm_owner)
return 0;
if (!XFS_RMAP_NON_INODE_OWNER(rec->rm_owner) &&
!(rec->rm_flags & XFS_RMAP_BMBT_BLOCK) &&
rec->rm_offset + rec->rm_blockcount - 1 != info->high.rm_offset)
return 0;
*info->irec = *rec;
*info->stat = 1;
return -ECANCELED;
}
/*
* Find the record to the left of the given extent, being careful only to
* return a match with the same owner and adjacent physical and logical
* block ranges.
*/
int
xfs_rmap_find_left_neighbor(
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)
{
struct xfs_find_left_neighbor_info info;
int error;
*stat = 0;
if (bno == 0)
return 0;
info.high.rm_startblock = bno - 1;
info.high.rm_owner = owner;
if (!XFS_RMAP_NON_INODE_OWNER(owner) &&
!(flags & XFS_RMAP_BMBT_BLOCK)) {
if (offset == 0)
return 0;
info.high.rm_offset = offset - 1;
} else
info.high.rm_offset = 0;
info.high.rm_flags = flags;
info.high.rm_blockcount = 0;
info.irec = irec;
info.stat = stat;
trace_xfs_rmap_find_left_neighbor_query(cur->bc_mp,
cur->bc_ag.pag->pag_agno, bno, 0, owner, offset, flags);
error = xfs_rmap_query_range(cur, &info.high, &info.high,
xfs_rmap_find_left_neighbor_helper, &info);
if (error == -ECANCELED)
error = 0;
if (*stat)
trace_xfs_rmap_find_left_neighbor_result(cur->bc_mp,
cur->bc_ag.pag->pag_agno, irec->rm_startblock,
irec->rm_blockcount, irec->rm_owner,
irec->rm_offset, irec->rm_flags);
return error;
}
/* For each rmap given, figure out if it matches the key we want. */
STATIC int
xfs_rmap_lookup_le_range_helper(
struct xfs_btree_cur *cur,
const struct xfs_rmap_irec *rec,
void *priv)
{
struct xfs_find_left_neighbor_info *info = priv;
trace_xfs_rmap_lookup_le_range_candidate(cur->bc_mp,
cur->bc_ag.pag->pag_agno, rec->rm_startblock,
rec->rm_blockcount, rec->rm_owner, rec->rm_offset,
rec->rm_flags);
if (rec->rm_owner != info->high.rm_owner)
return 0;
if (!XFS_RMAP_NON_INODE_OWNER(rec->rm_owner) &&
!(rec->rm_flags & XFS_RMAP_BMBT_BLOCK) &&
(rec->rm_offset > info->high.rm_offset ||
rec->rm_offset + rec->rm_blockcount <= info->high.rm_offset))
return 0;
*info->irec = *rec;
*info->stat = 1;
return -ECANCELED;
}
/*
* Find the record to the left of the given extent, being careful only to
* return a match with the same owner and overlapping physical and logical
* block ranges. This is the overlapping-interval version of
* xfs_rmap_lookup_le.
*/
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)
{
struct xfs_find_left_neighbor_info info;
int error;
info.high.rm_startblock = bno;
info.high.rm_owner = owner;
if (!XFS_RMAP_NON_INODE_OWNER(owner) && !(flags & XFS_RMAP_BMBT_BLOCK))
info.high.rm_offset = offset;
else
info.high.rm_offset = 0;
info.high.rm_flags = flags;
info.high.rm_blockcount = 0;
*stat = 0;
info.irec = irec;
info.stat = stat;
trace_xfs_rmap_lookup_le_range(cur->bc_mp,
cur->bc_ag.pag->pag_agno, bno, 0, owner, offset, flags);
error = xfs_rmap_query_range(cur, &info.high, &info.high,
xfs_rmap_lookup_le_range_helper, &info);
if (error == -ECANCELED)
error = 0;
if (*stat)
trace_xfs_rmap_lookup_le_range_result(cur->bc_mp,
cur->bc_ag.pag->pag_agno, irec->rm_startblock,
irec->rm_blockcount, irec->rm_owner,
irec->rm_offset, irec->rm_flags);
return error;
}
/*
* Perform all the relevant owner checks for a removal op. If we're doing an
* unknown-owner removal then we have no owner information to check.
*/
static int
xfs_rmap_free_check_owner(
struct xfs_mount *mp,
uint64_t ltoff,
struct xfs_rmap_irec *rec,
xfs_filblks_t len,
uint64_t owner,
uint64_t offset,
unsigned int flags)
{
int error = 0;
if (owner == XFS_RMAP_OWN_UNKNOWN)
return 0;
/* Make sure the unwritten flag matches. */
if (XFS_IS_CORRUPT(mp,
(flags & XFS_RMAP_UNWRITTEN) !=
(rec->rm_flags & XFS_RMAP_UNWRITTEN))) {
error = -EFSCORRUPTED;
goto out;
}
/* Make sure the owner matches what we expect to find in the tree. */
if (XFS_IS_CORRUPT(mp, owner != rec->rm_owner)) {
error = -EFSCORRUPTED;
goto out;
}
/* Check the offset, if necessary. */
if (XFS_RMAP_NON_INODE_OWNER(owner))
goto out;
if (flags & XFS_RMAP_BMBT_BLOCK) {
if (XFS_IS_CORRUPT(mp,
!(rec->rm_flags & XFS_RMAP_BMBT_BLOCK))) {
error = -EFSCORRUPTED;
goto out;
}
} else {
if (XFS_IS_CORRUPT(mp, rec->rm_offset > offset)) {
error = -EFSCORRUPTED;
goto out;
}
if (XFS_IS_CORRUPT(mp,
offset + len > ltoff + rec->rm_blockcount)) {
error = -EFSCORRUPTED;
goto out;
}
}
out:
return error;
}
/*
* Find the extent in the rmap btree and remove it.
*
* The record we find should always be an exact match for the extent that we're
* looking for, since we insert them into the btree without modification.
*
* Special Case #1: when growing the filesystem, we "free" an extent when
* growing the last AG. This extent is new space and so it is not tracked as
* used space in the btree. The growfs code will pass in an owner of
* XFS_RMAP_OWN_NULL to indicate that it expected that there is no owner of this
* extent. We verify that - the extent lookup result in a record that does not
* overlap.
*
* Special Case #2: EFIs do not record the owner of the extent, so when
* recovering EFIs from the log we pass in XFS_RMAP_OWN_UNKNOWN to tell the rmap
* btree to ignore the owner (i.e. wildcard match) so we don't trigger
* corruption checks during log recovery.
*/
STATIC int
xfs_rmap_unmap(
struct xfs_btree_cur *cur,
xfs_agblock_t bno,
xfs_extlen_t len,
bool unwritten,
const struct xfs_owner_info *oinfo)
{
struct xfs_mount *mp = cur->bc_mp;
struct xfs_rmap_irec ltrec;
uint64_t ltoff;
int error = 0;
int i;
uint64_t owner;
uint64_t offset;
unsigned int flags;
bool ignore_off;
xfs_owner_info_unpack(oinfo, &owner, &offset, &flags);
ignore_off = XFS_RMAP_NON_INODE_OWNER(owner) ||
(flags & XFS_RMAP_BMBT_BLOCK);
if (unwritten)
flags |= XFS_RMAP_UNWRITTEN;
trace_xfs_rmap_unmap(mp, cur->bc_ag.pag->pag_agno, bno, len,
unwritten, oinfo);
/*
* We should always have a left record because there's a static record
* for the AG headers at rm_startblock == 0 created by mkfs/growfs that
* will not ever be removed from the tree.
*/
error = xfs_rmap_lookup_le(cur, bno, len, owner, offset, flags, &i);
if (error)
goto out_error;
if (XFS_IS_CORRUPT(mp, i != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
error = xfs_rmap_get_rec(cur, <rec, &i);
if (error)
goto out_error;
if (XFS_IS_CORRUPT(mp, i != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
trace_xfs_rmap_lookup_le_range_result(cur->bc_mp,
cur->bc_ag.pag->pag_agno, ltrec.rm_startblock,
ltrec.rm_blockcount, ltrec.rm_owner,
ltrec.rm_offset, ltrec.rm_flags);
ltoff = ltrec.rm_offset;
/*
* For growfs, the incoming extent must be beyond the left record we
* just found as it is new space and won't be used by anyone. This is
* just a corruption check as we don't actually do anything with this
* extent. Note that we need to use >= instead of > because it might
* be the case that the "left" extent goes all the way to EOFS.
*/
if (owner == XFS_RMAP_OWN_NULL) {
if (XFS_IS_CORRUPT(mp,
bno <
ltrec.rm_startblock + ltrec.rm_blockcount)) {
error = -EFSCORRUPTED;
goto out_error;
}
goto out_done;
}
/*
* If we're doing an unknown-owner removal for EFI recovery, we expect
* to find the full range in the rmapbt or nothing at all. If we
* don't find any rmaps overlapping either end of the range, we're
* done. Hopefully this means that the EFI creator already queued
* (and finished) a RUI to remove the rmap.
*/
if (owner == XFS_RMAP_OWN_UNKNOWN &&
ltrec.rm_startblock + ltrec.rm_blockcount <= bno) {
struct xfs_rmap_irec rtrec;
error = xfs_btree_increment(cur, 0, &i);
if (error)
goto out_error;
if (i == 0)
goto out_done;
error = xfs_rmap_get_rec(cur, &rtrec, &i);
if (error)
goto out_error;
if (XFS_IS_CORRUPT(mp, i != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
if (rtrec.rm_startblock >= bno + len)
goto out_done;
}
/* Make sure the extent we found covers the entire freeing range. */
if (XFS_IS_CORRUPT(mp,
ltrec.rm_startblock > bno ||
ltrec.rm_startblock + ltrec.rm_blockcount <
bno + len)) {
error = -EFSCORRUPTED;
goto out_error;
}
/* Check owner information. */
error = xfs_rmap_free_check_owner(mp, ltoff, <rec, len, owner,
offset, flags);
if (error)
goto out_error;
if (ltrec.rm_startblock == bno && ltrec.rm_blockcount == len) {
/* exact match, simply remove the record from rmap tree */
trace_xfs_rmap_delete(mp, cur->bc_ag.pag->pag_agno,
ltrec.rm_startblock, ltrec.rm_blockcount,
ltrec.rm_owner, ltrec.rm_offset,
ltrec.rm_flags);
error = xfs_btree_delete(cur, &i);
if (error)
goto out_error;
if (XFS_IS_CORRUPT(mp, i != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
} else if (ltrec.rm_startblock == bno) {
/*
* overlap left hand side of extent: move the start, trim the
* length and update the current record.
*
* ltbno ltlen
* Orig: |oooooooooooooooooooo|
* Freeing: |fffffffff|
* Result: |rrrrrrrrrr|
* bno len
*/
ltrec.rm_startblock += len;
ltrec.rm_blockcount -= len;
if (!ignore_off)
ltrec.rm_offset += len;
error = xfs_rmap_update(cur, <rec);
if (error)
goto out_error;
} else if (ltrec.rm_startblock + ltrec.rm_blockcount == bno + len) {
/*
* overlap right hand side of extent: trim the length and update
* the current record.
*
* ltbno ltlen
* Orig: |oooooooooooooooooooo|
* Freeing: |fffffffff|
* Result: |rrrrrrrrrr|
* bno len
*/
ltrec.rm_blockcount -= len;
error = xfs_rmap_update(cur, <rec);
if (error)
goto out_error;
} else {
/*
* overlap middle of extent: trim the length of the existing
* record to the length of the new left-extent size, increment
* the insertion position so we can insert a new record
* containing the remaining right-extent space.
*
* ltbno ltlen
* Orig: |oooooooooooooooooooo|
* Freeing: |fffffffff|
* Result: |rrrrr| |rrrr|
* bno len
*/
xfs_extlen_t orig_len = ltrec.rm_blockcount;
ltrec.rm_blockcount = bno - ltrec.rm_startblock;
error = xfs_rmap_update(cur, <rec);
if (error)
goto out_error;
error = xfs_btree_increment(cur, 0, &i);
if (error)
goto out_error;
cur->bc_rec.r.rm_startblock = bno + len;
cur->bc_rec.r.rm_blockcount = orig_len - len -
ltrec.rm_blockcount;
cur->bc_rec.r.rm_owner = ltrec.rm_owner;
if (ignore_off)
cur->bc_rec.r.rm_offset = 0;
else
cur->bc_rec.r.rm_offset = offset + len;
cur->bc_rec.r.rm_flags = flags;
trace_xfs_rmap_insert(mp, cur->bc_ag.pag->pag_agno,
cur->bc_rec.r.rm_startblock,
cur->bc_rec.r.rm_blockcount,
cur->bc_rec.r.rm_owner,
cur->bc_rec.r.rm_offset,
cur->bc_rec.r.rm_flags);
error = xfs_btree_insert(cur, &i);
if (error)
goto out_error;
}
out_done:
trace_xfs_rmap_unmap_done(mp, cur->bc_ag.pag->pag_agno, bno, len,
unwritten, oinfo);
out_error:
if (error)
trace_xfs_rmap_unmap_error(mp, cur->bc_ag.pag->pag_agno,
error, _RET_IP_);
return error;
}
/*
* Remove a reference to an extent in the rmap btree.
*/
int
xfs_rmap_free(
struct xfs_trans *tp,
struct xfs_buf *agbp,
struct xfs_perag *pag,
xfs_agblock_t bno,
xfs_extlen_t len,
const struct xfs_owner_info *oinfo)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_btree_cur *cur;
int error;
if (!xfs_has_rmapbt(mp))
return 0;
cur = xfs_rmapbt_init_cursor(mp, tp, agbp, pag);
error = xfs_rmap_unmap(cur, bno, len, false, oinfo);
xfs_btree_del_cursor(cur, error);
return error;
}
/*
* A mergeable rmap must have the same owner and the same values for
* the unwritten, attr_fork, and bmbt flags. The startblock and
* offset are checked separately.
*/
static bool
xfs_rmap_is_mergeable(
struct xfs_rmap_irec *irec,
uint64_t owner,
unsigned int flags)
{
if (irec->rm_owner == XFS_RMAP_OWN_NULL)
return false;
if (irec->rm_owner != owner)
return false;
if ((flags & XFS_RMAP_UNWRITTEN) ^
(irec->rm_flags & XFS_RMAP_UNWRITTEN))
return false;
if ((flags & XFS_RMAP_ATTR_FORK) ^
(irec->rm_flags & XFS_RMAP_ATTR_FORK))
return false;
if ((flags & XFS_RMAP_BMBT_BLOCK) ^
(irec->rm_flags & XFS_RMAP_BMBT_BLOCK))
return false;
return true;
}
/*
* When we allocate a new block, the first thing we do is add a reference to
* the extent in the rmap btree. This takes the form of a [agbno, length,
* owner, offset] record. Flags are encoded in the high bits of the offset
* field.
*/
STATIC int
xfs_rmap_map(
struct xfs_btree_cur *cur,
xfs_agblock_t bno,
xfs_extlen_t len,
bool unwritten,
const struct xfs_owner_info *oinfo)
{
struct xfs_mount *mp = cur->bc_mp;
struct xfs_rmap_irec ltrec;
struct xfs_rmap_irec gtrec;
int have_gt;
int have_lt;
int error = 0;
int i;
uint64_t owner;
uint64_t offset;
unsigned int flags = 0;
bool ignore_off;
xfs_owner_info_unpack(oinfo, &owner, &offset, &flags);
ASSERT(owner != 0);
ignore_off = XFS_RMAP_NON_INODE_OWNER(owner) ||
(flags & XFS_RMAP_BMBT_BLOCK);
if (unwritten)
flags |= XFS_RMAP_UNWRITTEN;
trace_xfs_rmap_map(mp, cur->bc_ag.pag->pag_agno, bno, len,
unwritten, oinfo);
ASSERT(!xfs_rmap_should_skip_owner_update(oinfo));
/*
* For the initial lookup, look for an exact match or the left-adjacent
* record for our insertion point. This will also give us the record for
* start block contiguity tests.
*/
error = xfs_rmap_lookup_le(cur, bno, len, owner, offset, flags,
&have_lt);
if (error)
goto out_error;
if (have_lt) {
error = xfs_rmap_get_rec(cur, <rec, &have_lt);
if (error)
goto out_error;
if (XFS_IS_CORRUPT(mp, have_lt != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
trace_xfs_rmap_lookup_le_range_result(cur->bc_mp,
cur->bc_ag.pag->pag_agno, ltrec.rm_startblock,
ltrec.rm_blockcount, ltrec.rm_owner,
ltrec.rm_offset, ltrec.rm_flags);
if (!xfs_rmap_is_mergeable(<rec, owner, flags))
have_lt = 0;
}
if (XFS_IS_CORRUPT(mp,
have_lt != 0 &&
ltrec.rm_startblock + ltrec.rm_blockcount > bno)) {
error = -EFSCORRUPTED;
goto out_error;
}
/*
* Increment the cursor to see if we have a right-adjacent record to our
* insertion point. This will give us the record for end block
* contiguity tests.
*/
error = xfs_btree_increment(cur, 0, &have_gt);
if (error)
goto out_error;
if (have_gt) {
error = xfs_rmap_get_rec(cur, >rec, &have_gt);
if (error)
goto out_error;
if (XFS_IS_CORRUPT(mp, have_gt != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
if (XFS_IS_CORRUPT(mp, bno + len > gtrec.rm_startblock)) {
error = -EFSCORRUPTED;
goto out_error;
}
trace_xfs_rmap_find_right_neighbor_result(cur->bc_mp,
cur->bc_ag.pag->pag_agno, gtrec.rm_startblock,
gtrec.rm_blockcount, gtrec.rm_owner,
gtrec.rm_offset, gtrec.rm_flags);
if (!xfs_rmap_is_mergeable(>rec, owner, flags))
have_gt = 0;
}
/*
* Note: cursor currently points one record to the right of ltrec, even
* if there is no record in the tree to the right.
*/
if (have_lt &&
ltrec.rm_startblock + ltrec.rm_blockcount == bno &&
(ignore_off || ltrec.rm_offset + ltrec.rm_blockcount == offset)) {
/*
* left edge contiguous, merge into left record.
*
* ltbno ltlen
* orig: |ooooooooo|
* adding: |aaaaaaaaa|
* result: |rrrrrrrrrrrrrrrrrrr|
* bno len
*/
ltrec.rm_blockcount += len;
if (have_gt &&
bno + len == gtrec.rm_startblock &&
(ignore_off || offset + len == gtrec.rm_offset) &&
(unsigned long)ltrec.rm_blockcount + len +
gtrec.rm_blockcount <= XFS_RMAP_LEN_MAX) {
/*
* right edge also contiguous, delete right record
* and merge into left record.
*
* ltbno ltlen gtbno gtlen
* orig: |ooooooooo| |ooooooooo|
* adding: |aaaaaaaaa|
* result: |rrrrrrrrrrrrrrrrrrrrrrrrrrrrr|
*/
ltrec.rm_blockcount += gtrec.rm_blockcount;
trace_xfs_rmap_delete(mp, cur->bc_ag.pag->pag_agno,
gtrec.rm_startblock,
gtrec.rm_blockcount,
gtrec.rm_owner,
gtrec.rm_offset,
gtrec.rm_flags);
error = xfs_btree_delete(cur, &i);
if (error)
goto out_error;
if (XFS_IS_CORRUPT(mp, i != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
}
/* point the cursor back to the left record and update */
error = xfs_btree_decrement(cur, 0, &have_gt);
if (error)
goto out_error;
error = xfs_rmap_update(cur, <rec);
if (error)
goto out_error;
} else if (have_gt &&
bno + len == gtrec.rm_startblock &&
(ignore_off || offset + len == gtrec.rm_offset)) {
/*
* right edge contiguous, merge into right record.
*
* gtbno gtlen
* Orig: |ooooooooo|
* adding: |aaaaaaaaa|
* Result: |rrrrrrrrrrrrrrrrrrr|
* bno len
*/
gtrec.rm_startblock = bno;
gtrec.rm_blockcount += len;
if (!ignore_off)
gtrec.rm_offset = offset;
error = xfs_rmap_update(cur, >rec);
if (error)
goto out_error;
} else {
/*
* no contiguous edge with identical owner, insert
* new record at current cursor position.
*/
cur->bc_rec.r.rm_startblock = bno;
cur->bc_rec.r.rm_blockcount = len;
cur->bc_rec.r.rm_owner = owner;
cur->bc_rec.r.rm_offset = offset;
cur->bc_rec.r.rm_flags = flags;
trace_xfs_rmap_insert(mp, cur->bc_ag.pag->pag_agno, bno, len,
owner, offset, flags);
error = xfs_btree_insert(cur, &i);
if (error)
goto out_error;
if (XFS_IS_CORRUPT(mp, i != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
}
trace_xfs_rmap_map_done(mp, cur->bc_ag.pag->pag_agno, bno, len,
unwritten, oinfo);
out_error:
if (error)
trace_xfs_rmap_map_error(mp, cur->bc_ag.pag->pag_agno,
error, _RET_IP_);
return error;
}
/*
* Add a reference to an extent in the rmap btree.
*/
int
xfs_rmap_alloc(
struct xfs_trans *tp,
struct xfs_buf *agbp,
struct xfs_perag *pag,
xfs_agblock_t bno,
xfs_extlen_t len,
const struct xfs_owner_info *oinfo)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_btree_cur *cur;
int error;
if (!xfs_has_rmapbt(mp))
return 0;
cur = xfs_rmapbt_init_cursor(mp, tp, agbp, pag);
error = xfs_rmap_map(cur, bno, len, false, oinfo);
xfs_btree_del_cursor(cur, error);
return error;
}
#define RMAP_LEFT_CONTIG (1 << 0)
#define RMAP_RIGHT_CONTIG (1 << 1)
#define RMAP_LEFT_FILLING (1 << 2)
#define RMAP_RIGHT_FILLING (1 << 3)
#define RMAP_LEFT_VALID (1 << 6)
#define RMAP_RIGHT_VALID (1 << 7)
#define LEFT r[0]
#define RIGHT r[1]
#define PREV r[2]
#define NEW r[3]
/*
* Convert an unwritten extent to a real extent or vice versa.
* Does not handle overlapping extents.
*/
STATIC int
xfs_rmap_convert(
struct xfs_btree_cur *cur,
xfs_agblock_t bno,
xfs_extlen_t len,
bool unwritten,
const struct xfs_owner_info *oinfo)
{
struct xfs_mount *mp = cur->bc_mp;
struct xfs_rmap_irec r[4]; /* neighbor extent entries */
/* left is 0, right is 1, */
/* prev is 2, new is 3 */
uint64_t owner;