// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2003,2005 Silicon Graphics, 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_inode.h"
#include "xfs_trans.h"
#include "xfs_alloc.h"
#include "xfs_btree.h"
#include "xfs_btree_staging.h"
#include "xfs_bmap_btree.h"
#include "xfs_bmap.h"
#include "xfs_error.h"
#include "xfs_quota.h"
#include "xfs_trace.h"
#include "xfs_rmap.h"
#include "xfs_ag.h"
static struct kmem_cache *xfs_bmbt_cur_cache;
void
xfs_bmbt_init_block(
struct xfs_inode *ip,
struct xfs_btree_block *buf,
struct xfs_buf *bp,
__u16 level,
__u16 numrecs)
{
if (bp)
xfs_btree_init_buf(ip->i_mount, bp, &xfs_bmbt_ops, level,
numrecs, ip->i_ino);
else
xfs_btree_init_block(ip->i_mount, buf, &xfs_bmbt_ops, level,
numrecs, ip->i_ino);
}
/*
* Convert on-disk form of btree root to in-memory form.
*/
void
xfs_bmdr_to_bmbt(
struct xfs_inode *ip,
xfs_bmdr_block_t *dblock,
int dblocklen,
struct xfs_btree_block *rblock,
int rblocklen)
{
struct xfs_mount *mp = ip->i_mount;
int dmxr;
xfs_bmbt_key_t *fkp;
__be64 *fpp;
xfs_bmbt_key_t *tkp;
__be64 *tpp;
xfs_bmbt_init_block(ip, rblock, NULL, 0, 0);
rblock->bb_level = dblock->bb_level;
ASSERT(be16_to_cpu(rblock->bb_level) > 0);
rblock->bb_numrecs = dblock->bb_numrecs;
dmxr = xfs_bmdr_maxrecs(dblocklen, 0);
fkp = xfs_bmdr_key_addr(dblock, 1);
tkp = xfs_bmbt_key_addr(mp, rblock, 1);
fpp = xfs_bmdr_ptr_addr(dblock, 1, dmxr);
tpp = xfs_bmap_broot_ptr_addr(mp, rblock, 1, rblocklen);
dmxr = be16_to_cpu(dblock->bb_numrecs);
memcpy(tkp, fkp, sizeof(*fkp) * dmxr);
memcpy(tpp, fpp, sizeof(*fpp) * dmxr);
}
void
xfs_bmbt_disk_get_all(
const struct xfs_bmbt_rec *rec,
struct xfs_bmbt_irec *irec)
{
uint64_t l0 = get_unaligned_be64(&rec->l0);
uint64_t l1 = get_unaligned_be64(&rec->l1);
irec->br_startoff = (l0 & xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
irec->br_startblock = ((l0 & xfs_mask64lo(9)) << 43) | (l1 >> 21);
irec->br_blockcount = l1 & xfs_mask64lo(21);
if (l0 >> (64 - BMBT_EXNTFLAG_BITLEN))
irec->br_state = XFS_EXT_UNWRITTEN;
else
irec->br_state = XFS_EXT_NORM;
}
/*
* Extract the blockcount field from an on disk bmap extent record.
*/
xfs_filblks_t
xfs_bmbt_disk_get_blockcount(
const struct xfs_bmbt_rec *r)
{
return (xfs_filblks_t)(be64_to_cpu(r->l1) & xfs_mask64lo(21));
}
/*
* Extract the startoff field from a disk format bmap extent record.
*/
xfs_fileoff_t
xfs_bmbt_disk_get_startoff(
const struct xfs_bmbt_rec *r)
{
return ((xfs_fileoff_t)be64_to_cpu(r->l0) &
xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
}
/*
* Set all the fields in a bmap extent record from the uncompressed form.
*/
void
xfs_bmbt_disk_set_all(
struct xfs_bmbt_rec *r,
struct xfs_bmbt_irec *s)
{
int extent_flag = (s->br_state != XFS_EXT_NORM);
ASSERT(s->br_state == XFS_EXT_NORM || s->br_state == XFS_EXT_UNWRITTEN);
ASSERT(!(s->br_startoff & xfs_mask64hi(64-BMBT_STARTOFF_BITLEN)));
ASSERT(!(s->br_blockcount & xfs_mask64hi(64-BMBT_BLOCKCOUNT_BITLEN)));
ASSERT(!(s->br_startblock & xfs_mask64hi(64-BMBT_STARTBLOCK_BITLEN)));
put_unaligned_be64(
((xfs_bmbt_rec_base_t)extent_flag << 63) |
((xfs_bmbt_rec_base_t)s->br_startoff << 9) |
((xfs_bmbt_rec_base_t)s->br_startblock >> 43), &r->l0);
put_unaligned_be64(
((xfs_bmbt_rec_base_t)s->br_startblock << 21) |
((xfs_bmbt_rec_base_t)s->br_blockcount &
(xfs_bmbt_rec_base_t)xfs_mask64lo(21)), &r->l1);
}
/*
* Convert in-memory form of btree root to on-disk form.
*/
void
xfs_bmbt_to_bmdr(
struct xfs_mount *mp,
struct xfs_btree_block *rblock,
int rblocklen,
xfs_bmdr_block_t *dblock,
int dblocklen)
{
int dmxr;
xfs_bmbt_key_t *fkp;
__be64 *fpp;
xfs_bmbt_key_t *tkp;
__be64 *tpp;
if (xfs_has_crc(mp)) {
ASSERT(rblock->bb_magic == cpu_to_be32(XFS_BMAP_CRC_MAGIC));
ASSERT(uuid_equal(&rblock->bb_u.l.bb_uuid,
&mp->m_sb.sb_meta_uuid));
ASSERT(rblock->bb_u.l.bb_blkno ==
cpu_to_be64(XFS_BUF_DADDR_NULL));
} else
ASSERT(rblock->bb_magic == cpu_to_be32(XFS_BMAP_MAGIC));
ASSERT(rblock->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK));
ASSERT(rblock->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK));
ASSERT(rblock->bb_level != 0);
dblock->bb_level = rblock->bb_level;
dblock->bb_numrecs = rblock->bb_numrecs;
dmxr = xfs_bmdr_maxrecs(dblocklen, 0);
fkp = xfs_bmbt_key_addr(mp, rblock, 1);
tkp = xfs_bmdr_key_addr(dblock, 1);
fpp = xfs_bmap_broot_ptr_addr(mp, rblock, 1, rblocklen);
tpp = xfs_bmdr_ptr_addr(dblock, 1, dmxr);
dmxr = be16_to_cpu(dblock->bb_numrecs);
memcpy(tkp, fkp, sizeof(*fkp) * dmxr);
memcpy(tpp, fpp, sizeof(*fpp) * dmxr);
}
STATIC struct xfs_btree_cur *
xfs_bmbt_dup_cursor(
struct xfs_btree_cur *cur)
{
struct xfs_btree_cur *new;
new = xfs_bmbt_init_cursor(cur->bc_mp, cur->bc_tp,
cur->bc_ino.ip, cur->bc_ino.whichfork);
new->bc_flags |= (cur->bc_flags &
(XFS_BTREE_BMBT_INVALID_OWNER | XFS_BTREE_BMBT_WASDEL));
return new;
}
STATIC void
xfs_bmbt_update_cursor(
struct xfs_btree_cur *src,
struct xfs_btree_cur *dst)
{
ASSERT((dst->bc_tp->t_highest_agno != NULLAGNUMBER) ||
(dst->bc_ino.ip->i_diflags & XFS_DIFLAG_REALTIME));
dst->bc_bmap.allocated += src->bc_bmap.allocated;
dst->bc_tp->t_highest_agno = src->bc_tp->t_highest_agno;
src->bc_bmap.allocated = 0;
}
STATIC int
xfs_bmbt_alloc_block(
struct xfs_btree_cur *cur,
const union xfs_btree_ptr *start,
union xfs_btree_ptr *new,
int *stat)
{
struct xfs_alloc_arg args;
int error;
memset(&args, 0, sizeof(args));
args.tp = cur->bc_tp;
args.mp = cur->bc_mp;
xfs_rmap_ino_bmbt_owner(&args.oinfo, cur->bc_ino.ip->i_ino,
cur->bc_ino.whichfork);
args.minlen = args.maxlen = args.prod = 1;
args.wasdel = cur->bc_flags & XFS_BTREE_BMBT_WASDEL;
if (!args.wasdel && args.tp->t_blk_res == 0)
return -ENOSPC;
/*
* If we are coming here from something like unwritten extent
* conversion, there has been no data extent allocation already done, so
* we have to ensure that we attempt to locate the entire set of bmbt
* allocations in the same AG, as xfs_bmapi_write() would have reserved.
*/
if (cur->bc_tp->t_highest_agno == NULLAGNUMBER)
args.minleft = xfs_bmapi_minleft(cur->bc_tp, cur->bc_ino.ip,
cur->bc_ino.whichfork);
error = xfs_alloc_vextent_start_ag(&args, be64_to_cpu(start->l));
if (error)
return error;
if (args.fsbno == NULLFSBLOCK && args.minleft) {
/*
* Could not find an AG with enough free space to satisfy
* a full btree split. Try again and if
* successful activate the lowspace algorithm.
*/
args.minleft = 0;
error = xfs_alloc_vextent_start_ag(&args, 0);
if (error)
return error;
cur->bc_tp->t_flags |= XFS_TRANS_LOWMODE;
}
if (WARN_ON_ONCE(args.fsbno == NULLFSBLOCK)) {
*stat = 0;
return 0;
}
ASSERT(args.len == 1);
cur->bc_bmap.allocated++;
cur->bc_ino.ip->i_nblocks++;
xfs_trans_log_inode(args.tp, cur->bc_ino.ip, XFS_ILOG_CORE);
xfs_trans_mod_dquot_byino(args.tp, cur->bc_ino.ip,
XFS_TRANS_DQ_BCOUNT, 1L);
new->l = cpu_to_be64(args.fsbno);
*stat = 1;
return 0;
}
STATIC int
xfs_bmbt_free_block(
struct xfs_btree_cur *cur,
struct xfs_buf *bp)
{
struct xfs_mount *mp = cur->bc_mp;
struct xfs_inode *ip = cur->bc_ino.ip;
struct xfs_trans *tp = cur->bc_tp;
xfs_fsblock_t fsbno = XFS_DADDR_TO_FSB(mp, xfs_buf_daddr(bp));
struct xfs_owner_info oinfo;
int error;
xfs_rmap_ino_bmbt_owner(&oinfo, ip->i_ino, cur->bc_ino.whichfork);
error = xfs_free_extent_later(cur->bc_tp, fsbno, 1, &oinfo,
XFS_AG_RESV_NONE, 0);
if (error)
return error;
ip->i_nblocks--;
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
return 0;
}
STATIC int
xfs_bmbt_get_minrecs(
struct xfs_btree_cur *cur,
int level)
{
if (level == cur->bc_nlevels - 1) {
struct xfs_ifork *ifp = xfs_btree_ifork_ptr(cur);
return xfs_bmbt_maxrecs(cur->bc_mp,
ifp->if_broot_bytes, level == 0) / 2;
}
return cur->bc_mp->m_bmap_dmnr[level != 0];
}
int
xfs_bmbt_get_maxrecs(
struct xfs_btree_cur *cur,
int level)
{
if (level == cur->bc_nlevels - 1) {
struct xfs_ifork *ifp = xfs_btree_ifork_ptr(cur);
return xfs_bmbt_maxrecs(cur->bc_mp,
ifp->if_broot_bytes, level == 0);
}
return cur->bc_mp->m_bmap_dmxr[level != 0];
}
/*
* Get the maximum records we could store in the on-disk format.
*
* For non-root nodes this is equivalent to xfs_bmbt_get_maxrecs, but
* for the root node this checks the available space in the dinode fork
* so that we can resize the in-memory buffer to match it. After a
* resize to the maximum size this function returns the same value
* as xfs_bmbt_get_maxrecs for the root node, too.
*/
STATIC int
xfs_bmbt_get_dmaxrecs(
struct xfs_btree_cur *cur,
int level)
{
if (level != cur->bc_nlevels - 1)
return cur->bc_mp->m_bmap_dmxr[level != 0];
return xfs_bmdr_maxrecs(cur->bc_ino.forksize, level == 0);
}
STATIC void
xfs_bmbt_init_key_from_rec(
union xfs_btree_key *key,
const union xfs_btree_rec *rec)
{
key->bmbt.br_startoff =
cpu_to_be64(xfs_bmbt_disk_get_startoff(&rec->bmbt));
}
STATIC void
xfs_bmbt_init_high_key_from_rec(
union xfs_btree_key *key,
const union xfs_btree_rec *rec)
{
key->bmbt.br_startoff = cpu_to_be64(
xfs_bmbt_disk_get_startoff(&rec->bmbt) +
xfs_bmbt_disk_get_blockcount(&rec->bmbt) - 1);
}
STATIC void
xfs_bmbt_init_rec_from_cur(
struct xfs_btree_cur *cur,
union xfs_btree_rec *rec)
{
xfs_bmbt_disk_set_all(&rec->bmbt, &cur->bc_rec.b);
}
STATIC int64_t
xfs_bmbt_key_diff(
struct xfs_btree_cur *cur,
const union xfs_btree_key *key)
{
return (int64_t)be64_to_cpu(key->bmbt.br_startoff) -
cur->bc_rec.b.br_startoff;
}
STATIC int64_t
xfs_bmbt_diff_two_keys(
struct xfs_btree_cur *cur,
const union xfs_btree_key *k1,
const union xfs_btree_key *k2,
const union xfs_btree_key *mask)
{
uint64_t a = be64_to_cpu(k1->bmbt.br_startoff);
uint64_t b = be64_to_cpu(k2->bmbt.br_startoff);
ASSERT(!mask || mask->bmbt.br_startoff);
/*
* Note: This routine previously casted a and b to int64 and subtracted
* them to generate a result. This lead to problems if b was the
* "maximum" key value (all ones) being signed incorrectly, hence this
* somewhat less efficient version.
*/
if (a > b)
return 1;
if (b > a)
return -1;
return 0;
}
static xfs_failaddr_t
xfs_bmbt_verify(
struct xfs_buf *bp)
{
struct xfs_mount *mp = bp->b_mount;
struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
xfs_failaddr_t fa;
unsigned int level;
if (!xfs_verify_magic(bp, block->bb_magic))
return __this_address;
if (xfs_has_crc(mp)) {
/*
* XXX: need a better way of verifying the owner here. Right now
* just make sure there has been one set.
*/
fa = xfs_btree_fsblock_v5hdr_verify(bp, XFS_RMAP_OWN_UNKNOWN);
if (fa)
return fa;
}
/*
* numrecs and level verification.
*
* We don't know what fork we belong to, so just verify that the level
* is less than the maximum of the two. Later checks will be more
* precise.
*/
level = be16_to_cpu(block->bb_level);
if (level > max(mp->m_bm_maxlevels[0], mp->m_bm_maxlevels[1]))
return __this_address;
return xfs_btree_fsblock_verify(bp, mp->m_bmap_dmxr[level != 0]);
}
static void
xfs_bmbt_read_verify(
struct xfs_buf *bp)
{
xfs_failaddr_t fa;
if (!xfs_btree_fsblock_verify_crc(bp))
xfs_verifier_error(bp, -EFSBADCRC, __this_address);
else {
fa = xfs_bmbt_verify(bp);
if (fa)
xfs_verifier_error(bp, -EFSCORRUPTED, fa);
}
if (bp->b_error)
trace_xfs_btree_corrupt(bp, _RET_IP_);
}
static void
xfs_bmbt_write_verify(
struct xfs_buf *bp)
{
xfs_failaddr_t fa;
fa = xfs_bmbt_verify(bp);
if (fa) {
trace_xfs_btree_corrupt(bp, _RET_IP_);
xfs_verifier_error(bp, -EFSCORRUPTED, fa);
return;
}
xfs_btree_fsblock_calc_crc(bp);
}
const struct xfs_buf_ops xfs_bmbt_buf_ops = {
.name = "xfs_bmbt",
.magic = { cpu_to_be32(XFS_BMAP_MAGIC),
cpu_to_be32(XFS_BMAP_CRC_MAGIC) },
.verify_read = xfs_bmbt_read_verify,
.verify_write = xfs_bmbt_write_verify,
.verify_struct = xfs_bmbt_verify,
};
STATIC int
xfs_bmbt_keys_inorder(
struct xfs_btree_cur *cur,
const union xfs_btree_key *k1,
const union xfs_btree_key *k2)
{
return be64_to_cpu(k1->bmbt.br_startoff) <
be64_to_cpu(k2->bmbt.br_startoff);
}
STATIC int
xfs_bmbt_recs_inorder(
struct xfs_btree_cur *cur,
const union xfs_btree_rec *r1,
const union xfs_btree_rec *r2)
{
return xfs_bmbt_disk_get_startoff(&r1->bmbt) +
xfs_bmbt_disk_get_blockcount(&r1->bmbt) <=
xfs_bmbt_disk_get_startoff(&r2->bmbt);
}
STATIC enum xbtree_key_contig
xfs_bmbt_keys_contiguous(
struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2,
const union xfs_btree_key *mask)
{
ASSERT(!mask || mask->bmbt.br_startoff);
return xbtree_key_contig(be64_to_cpu(key1->bmbt.br_startoff),
be64_to_cpu(key2->bmbt.br_startoff));
}
const struct xfs_btree_ops xfs_bmbt_ops = {
.name = "bmap",
.type = XFS_BTREE_TYPE_INODE,
.rec_len = sizeof(xfs_bmbt_rec_t),
.key_len = sizeof(xfs_bmbt_key_t),
.ptr_len = XFS_BTREE_LONG_PTR_LEN,
.lru_refs = XFS_BMAP_BTREE_REF,
.statoff = XFS_STATS_CALC_INDEX(xs_bmbt_2),
.dup_cursor = xfs_bmbt_dup_cursor,
.update_cursor = xfs_bmbt_update_cursor,
.alloc_block = xfs_bmbt_alloc_block,
.free_block = xfs_bmbt_free_block,
.get_maxrecs = xfs_bmbt_get_maxrecs,
.get_minrecs = xfs_bmbt_get_minrecs,
.get_dmaxrecs = xfs_bmbt_get_dmaxrecs,
.init_key_from_rec = xfs_bmbt_init_key_from_rec,
.init_high_key_from_rec = xfs_bmbt_init_high_key_from_rec,
.init_rec_from_cur = xfs_bmbt_init_rec_from_cur,
.key_diff = xfs_bmbt_key_diff,
.diff_two_keys = xfs_bmbt_diff_two_keys,
.buf_ops = &xfs_bmbt_buf_ops,
.keys_inorder = xfs_bmbt_keys_inorder,
.recs_inorder = xfs_bmbt_recs_inorder,
.keys_contiguous = xfs_bmbt_keys_contiguous,
};
/*
* Create a new bmap btree cursor.
*
* For staging cursors -1 in passed in whichfork.
*/
struct xfs_btree_cur *
xfs_bmbt_init_cursor(
struct xfs_mount *mp,
struct xfs_trans *tp,
struct xfs_inode *ip,
int whichfork)
{
struct xfs_btree_cur *cur;
unsigned int maxlevels;
ASSERT(whichfork != XFS_COW_FORK);
/*
* The Data fork always has larger maxlevel, so use that for staging
* cursors.
*/
switch (whichfork) {
case XFS_STAGING_FORK:
maxlevels = mp->m_bm_maxlevels[XFS_DATA_FORK];
break;
default:
maxlevels = mp->m_bm_maxlevels[whichfork];
break;
}
cur = xfs_btree_alloc_cursor(mp, tp, &xfs_bmbt_ops, maxlevels,
xfs_bmbt_cur_cache);
cur->bc_ino.ip = ip;
cur->bc_ino.whichfork = whichfork;
cur->bc_bmap.allocated = 0;
if (whichfork != XFS_STAGING_FORK) {
struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork);
cur->bc_nlevels = be16_to_cpu(ifp->if_broot->bb_level) + 1;
cur->bc_ino.forksize = xfs_inode_fork_size(ip, whichfork);
}
return cur;
}
/* Calculate number of records in a block mapping btree block. */
static inline unsigned int
xfs_bmbt_block_maxrecs(
unsigned int blocklen,
bool leaf)
{
if (leaf)
return blocklen / sizeof(xfs_bmbt_rec_t);
return blocklen / (sizeof(xfs_bmbt_key_t) + sizeof(xfs_bmbt_ptr_t));
}
/*
* Swap in the new inode fork root. Once we pass this point the newly rebuilt
* mappings are in place and we have to kill off any old btree blocks.
*/
void
xfs_bmbt_commit_staged_btree(
struct xfs_btree_cur *cur,
struct xfs_trans *tp,
int whichfork)
{
struct xbtree_ifakeroot *ifake = cur->bc_ino.ifake;
struct xfs_ifork *ifp;
static const short brootflag[2] = {XFS_ILOG_DBROOT, XFS_ILOG_ABROOT};
static const short extflag[2] = {XFS_ILOG_DEXT, XFS_ILOG_AEXT};
int flags = XFS_ILOG_CORE;
ASSERT(cur->bc_flags & XFS_BTREE_STAGING);
ASSERT(whichfork != XFS_COW_FORK);
/*
* Free any resources hanging off the real fork, then shallow-copy the
* staging fork's contents into the real fork to transfer everything
* we just built.
*/
ifp = xfs_ifork_ptr(cur->bc_ino.ip, whichfork);
xfs_idestroy_fork(ifp);
memcpy(ifp, ifake->if_fork, sizeof(struct xfs_ifork));
switch (ifp->if_format) {
case XFS_DINODE_FMT_EXTENTS:
flags |= extflag[whichfork];
break;
case XFS_DINODE_FMT_BTREE:
flags |= brootflag[whichfork];
break;
default:
ASSERT(0);
break;
}
xfs_trans_log_inode(tp, cur->bc_ino.ip, flags);
xfs_btree_commit_ifakeroot(cur, tp, whichfork);
}
/*
* Calculate number of records in a bmap btree block.
*/
unsigned int
xfs_bmbt_maxrecs(
struct xfs_mount *mp,
unsigned int blocklen,
bool leaf)
{
blocklen -= xfs_bmbt_block_len(mp);
return xfs_bmbt_block_maxrecs(blocklen, leaf);
}
/*
* Calculate the maximum possible height of the btree that the on-disk format
* supports. This is used for sizing structures large enough to support every
* possible configuration of a filesystem that might get mounted.
*/
unsigned int
xfs_bmbt_maxlevels_ondisk(void)
{
unsigned int minrecs[2];
unsigned int blocklen;
blocklen = min(XFS_MIN_BLOCKSIZE - XFS_BTREE_SBLOCK_LEN,
XFS_MIN_CRC_BLOCKSIZE - XFS_BTREE_SBLOCK_CRC_LEN);
minrecs[0] = xfs_bmbt_block_maxrecs(blocklen, true) / 2;
minrecs[1] = xfs_bmbt_block_maxrecs(blocklen, false) / 2;
/* One extra level for the inode root. */
return xfs_btree_compute_maxlevels(minrecs,
XFS_MAX_EXTCNT_DATA_FORK_LARGE) + 1;
}
/*
* Calculate number of records in a bmap btree inode root.
*/
int
xfs_bmdr_maxrecs(
int blocklen,
int leaf)
{
blocklen -= sizeof(xfs_bmdr_block_t);
if (leaf)
return blocklen / sizeof(xfs_bmdr_rec_t);
return blocklen / (sizeof(xfs_bmdr_key_t) + sizeof(xfs_bmdr_ptr_t));
}
/*
* Change the owner of a btree format fork fo the inode passed in. Change it to
* the owner of that is passed in so that we can change owners before or after
* we switch forks between inodes. The operation that the caller is doing will
* determine whether is needs to change owner before or after the switch.
*
* For demand paged transactional modification, the fork switch should be done
* after reading in all the blocks, modifying them and pinning them in the
* transaction. For modification when the buffers are already pinned in memory,
* the fork switch can be done before changing the owner as we won't need to
* validate the owner until the btree buffers are unpinned and writes can occur
* again.
*
* For recovery based ownership change, there is no transactional context and
* so a buffer list must be supplied so that we can record the buffers that we
* modified for the caller to issue IO on.
*/
int
xfs_bmbt_change_owner(
struct xfs_trans *tp,
struct xfs_inode *ip,
int whichfork,
xfs_ino_t new_owner,
struct list_head *buffer_list)
{
struct xfs_btree_cur *cur;
int error;
ASSERT(tp || buffer_list);
ASSERT(!(tp && buffer_list));
ASSERT(xfs_ifork_ptr(ip, whichfork)->if_format == XFS_DINODE_FMT_BTREE);
cur = xfs_bmbt_init_cursor(ip->i_mount, tp, ip, whichfork);
cur->bc_flags |= XFS_BTREE_BMBT_INVALID_OWNER;
error = xfs_btree_change_owner(cur, new_owner, buffer_list);
xfs_btree_del_cursor(cur, error);
return error;
}
/* Calculate the bmap btree size for some records. */
unsigned long long
xfs_bmbt_calc_size(
struct xfs_mount *mp,
unsigned long long len)
{
return xfs_btree_calc_size(mp->m_bmap_dmnr, len);
}
int __init
xfs_bmbt_init_cur_cache(void)
{
xfs_bmbt_cur_cache = kmem_cache_create("xfs_bmbt_cur",
xfs_btree_cur_sizeof(xfs_bmbt_maxlevels_ondisk()),
0, 0, NULL);
if (!xfs_bmbt_cur_cache)
return -ENOMEM;
return 0;
}
void
xfs_bmbt_destroy_cur_cache(void)
{
kmem_cache_destroy(xfs_bmbt_cur_cache);
xfs_bmbt_cur_cache = NULL;
}
Codebase Browser
linux