linux/fs/xfs/libxfs/xfs_ialloc.c
Dave Chinner 7a1df15616 xfs: fix premature enospc on inode allocation
After growing a filesystem, XFS can fail to allocate inodes even
though there is a large amount of space available in the filesystem
for inodes. The issue is caused by a nearly full allocation group
having enough free space in it to be considered for inode
allocation, but not enough contiguous free space to actually
allocation inodes.  This situation results in successful selection
of the AG for allocation, then failure of the allocation resulting
in ENOSPC being reported to the caller.

It is caused by two possible issues. Firstly, we only consider the
lognest free extent and whether it would fit an inode chunk. If the
extent is not correctly aligned, then we can't allocate an inode
chunk in it regardless of the fact that it is large enough. This
tends to be a permanent error until space in the AG is freed.

The second issue is that we don't actually lock the AGI or AGF when
we are doing these checks, and so by the time we get to actually
allocating the inode chunk the space we thought we had in the AG may
have been allocated. This tends to be a spurious error as it
requires a race to trigger. Hence this case is ignored in this patch
as the reported problem is for permanent errors.

The first issue could be addressed by simply taking into account the
alignment when checking the longest extent. This, however, would
prevent allocation in AGs that have aligned, exact sized extents
free. However, this case should be fairly rare compared to the
number of allocations that occur near ENOSPC that would trigger this
condition.

Hence, when selecting the inode AG, take into account the inode
cluster alignment when checking the lognest free extent in the AG.
If we can't find any AGs with a contiguous free space large
enough to be aligned, drop the alignment addition and just try for
an AG that has enough contiguous free space available for an inode
chunk. This won't prevent issues from occurring, but should avoid
situations where other AGs have lots of free space but the selected
AG can't allocate due to alignment constraints.

Reported-by: Arkadiusz Miskiewicz <arekm@maven.pl>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-12-04 09:42:21 +11:00

2201 lines
58 KiB
C

/*
* Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* 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.
*
* 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_bit.h"
#include "xfs_inum.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_ialloc_btree.h"
#include "xfs_alloc.h"
#include "xfs_rtalloc.h"
#include "xfs_error.h"
#include "xfs_bmap.h"
#include "xfs_cksum.h"
#include "xfs_trans.h"
#include "xfs_buf_item.h"
#include "xfs_icreate_item.h"
#include "xfs_icache.h"
#include "xfs_dinode.h"
#include "xfs_trace.h"
/*
* Allocation group level functions.
*/
static inline int
xfs_ialloc_cluster_alignment(
struct xfs_mount *mp)
{
if (xfs_sb_version_hasalign(&mp->m_sb) &&
mp->m_sb.sb_inoalignmt >=
XFS_B_TO_FSBT(mp, mp->m_inode_cluster_size))
return mp->m_sb.sb_inoalignmt;
return 1;
}
/*
* Lookup a record by ino in the btree given by cur.
*/
int /* error */
xfs_inobt_lookup(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_agino_t ino, /* starting inode of chunk */
xfs_lookup_t dir, /* <=, >=, == */
int *stat) /* success/failure */
{
cur->bc_rec.i.ir_startino = ino;
cur->bc_rec.i.ir_freecount = 0;
cur->bc_rec.i.ir_free = 0;
return xfs_btree_lookup(cur, dir, stat);
}
/*
* Update the record referred to by cur to the value given.
* This either works (return 0) or gets an EFSCORRUPTED error.
*/
STATIC int /* error */
xfs_inobt_update(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_inobt_rec_incore_t *irec) /* btree record */
{
union xfs_btree_rec rec;
rec.inobt.ir_startino = cpu_to_be32(irec->ir_startino);
rec.inobt.ir_freecount = cpu_to_be32(irec->ir_freecount);
rec.inobt.ir_free = cpu_to_be64(irec->ir_free);
return xfs_btree_update(cur, &rec);
}
/*
* Get the data from the pointed-to record.
*/
int /* error */
xfs_inobt_get_rec(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_inobt_rec_incore_t *irec, /* btree record */
int *stat) /* output: success/failure */
{
union xfs_btree_rec *rec;
int error;
error = xfs_btree_get_rec(cur, &rec, stat);
if (!error && *stat == 1) {
irec->ir_startino = be32_to_cpu(rec->inobt.ir_startino);
irec->ir_freecount = be32_to_cpu(rec->inobt.ir_freecount);
irec->ir_free = be64_to_cpu(rec->inobt.ir_free);
}
return error;
}
/*
* Insert a single inobt record. Cursor must already point to desired location.
*/
STATIC int
xfs_inobt_insert_rec(
struct xfs_btree_cur *cur,
__int32_t freecount,
xfs_inofree_t free,
int *stat)
{
cur->bc_rec.i.ir_freecount = freecount;
cur->bc_rec.i.ir_free = free;
return xfs_btree_insert(cur, stat);
}
/*
* Insert records describing a newly allocated inode chunk into the inobt.
*/
STATIC int
xfs_inobt_insert(
struct xfs_mount *mp,
struct xfs_trans *tp,
struct xfs_buf *agbp,
xfs_agino_t newino,
xfs_agino_t newlen,
xfs_btnum_t btnum)
{
struct xfs_btree_cur *cur;
struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
xfs_agino_t thisino;
int i;
int error;
cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, btnum);
for (thisino = newino;
thisino < newino + newlen;
thisino += XFS_INODES_PER_CHUNK) {
error = xfs_inobt_lookup(cur, thisino, XFS_LOOKUP_EQ, &i);
if (error) {
xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
return error;
}
ASSERT(i == 0);
error = xfs_inobt_insert_rec(cur, XFS_INODES_PER_CHUNK,
XFS_INOBT_ALL_FREE, &i);
if (error) {
xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
return error;
}
ASSERT(i == 1);
}
xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
return 0;
}
/*
* Verify that the number of free inodes in the AGI is correct.
*/
#ifdef DEBUG
STATIC int
xfs_check_agi_freecount(
struct xfs_btree_cur *cur,
struct xfs_agi *agi)
{
if (cur->bc_nlevels == 1) {
xfs_inobt_rec_incore_t rec;
int freecount = 0;
int error;
int i;
error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
if (error)
return error;
do {
error = xfs_inobt_get_rec(cur, &rec, &i);
if (error)
return error;
if (i) {
freecount += rec.ir_freecount;
error = xfs_btree_increment(cur, 0, &i);
if (error)
return error;
}
} while (i == 1);
if (!XFS_FORCED_SHUTDOWN(cur->bc_mp))
ASSERT(freecount == be32_to_cpu(agi->agi_freecount));
}
return 0;
}
#else
#define xfs_check_agi_freecount(cur, agi) 0
#endif
/*
* Initialise a new set of inodes. When called without a transaction context
* (e.g. from recovery) we initiate a delayed write of the inode buffers rather
* than logging them (which in a transaction context puts them into the AIL
* for writeback rather than the xfsbufd queue).
*/
int
xfs_ialloc_inode_init(
struct xfs_mount *mp,
struct xfs_trans *tp,
struct list_head *buffer_list,
xfs_agnumber_t agno,
xfs_agblock_t agbno,
xfs_agblock_t length,
unsigned int gen)
{
struct xfs_buf *fbuf;
struct xfs_dinode *free;
int nbufs, blks_per_cluster, inodes_per_cluster;
int version;
int i, j;
xfs_daddr_t d;
xfs_ino_t ino = 0;
/*
* Loop over the new block(s), filling in the inodes. For small block
* sizes, manipulate the inodes in buffers which are multiples of the
* blocks size.
*/
blks_per_cluster = xfs_icluster_size_fsb(mp);
inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
nbufs = length / blks_per_cluster;
/*
* Figure out what version number to use in the inodes we create. If
* the superblock version has caught up to the one that supports the new
* inode format, then use the new inode version. Otherwise use the old
* version so that old kernels will continue to be able to use the file
* system.
*
* For v3 inodes, we also need to write the inode number into the inode,
* so calculate the first inode number of the chunk here as
* XFS_OFFBNO_TO_AGINO() only works within a filesystem block, not
* across multiple filesystem blocks (such as a cluster) and so cannot
* be used in the cluster buffer loop below.
*
* Further, because we are writing the inode directly into the buffer
* and calculating a CRC on the entire inode, we have ot log the entire
* inode so that the entire range the CRC covers is present in the log.
* That means for v3 inode we log the entire buffer rather than just the
* inode cores.
*/
if (xfs_sb_version_hascrc(&mp->m_sb)) {
version = 3;
ino = XFS_AGINO_TO_INO(mp, agno,
XFS_OFFBNO_TO_AGINO(mp, agbno, 0));
/*
* log the initialisation that is about to take place as an
* logical operation. This means the transaction does not
* need to log the physical changes to the inode buffers as log
* recovery will know what initialisation is actually needed.
* Hence we only need to log the buffers as "ordered" buffers so
* they track in the AIL as if they were physically logged.
*/
if (tp)
xfs_icreate_log(tp, agno, agbno, mp->m_ialloc_inos,
mp->m_sb.sb_inodesize, length, gen);
} else
version = 2;
for (j = 0; j < nbufs; j++) {
/*
* Get the block.
*/
d = XFS_AGB_TO_DADDR(mp, agno, agbno + (j * blks_per_cluster));
fbuf = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
mp->m_bsize * blks_per_cluster,
XBF_UNMAPPED);
if (!fbuf)
return -ENOMEM;
/* Initialize the inode buffers and log them appropriately. */
fbuf->b_ops = &xfs_inode_buf_ops;
xfs_buf_zero(fbuf, 0, BBTOB(fbuf->b_length));
for (i = 0; i < inodes_per_cluster; i++) {
int ioffset = i << mp->m_sb.sb_inodelog;
uint isize = xfs_dinode_size(version);
free = xfs_make_iptr(mp, fbuf, i);
free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
free->di_version = version;
free->di_gen = cpu_to_be32(gen);
free->di_next_unlinked = cpu_to_be32(NULLAGINO);
if (version == 3) {
free->di_ino = cpu_to_be64(ino);
ino++;
uuid_copy(&free->di_uuid, &mp->m_sb.sb_uuid);
xfs_dinode_calc_crc(mp, free);
} else if (tp) {
/* just log the inode core */
xfs_trans_log_buf(tp, fbuf, ioffset,
ioffset + isize - 1);
}
}
if (tp) {
/*
* Mark the buffer as an inode allocation buffer so it
* sticks in AIL at the point of this allocation
* transaction. This ensures the they are on disk before
* the tail of the log can be moved past this
* transaction (i.e. by preventing relogging from moving
* it forward in the log).
*/
xfs_trans_inode_alloc_buf(tp, fbuf);
if (version == 3) {
/*
* Mark the buffer as ordered so that they are
* not physically logged in the transaction but
* still tracked in the AIL as part of the
* transaction and pin the log appropriately.
*/
xfs_trans_ordered_buf(tp, fbuf);
xfs_trans_log_buf(tp, fbuf, 0,
BBTOB(fbuf->b_length) - 1);
}
} else {
fbuf->b_flags |= XBF_DONE;
xfs_buf_delwri_queue(fbuf, buffer_list);
xfs_buf_relse(fbuf);
}
}
return 0;
}
/*
* Allocate new inodes in the allocation group specified by agbp.
* Return 0 for success, else error code.
*/
STATIC int /* error code or 0 */
xfs_ialloc_ag_alloc(
xfs_trans_t *tp, /* transaction pointer */
xfs_buf_t *agbp, /* alloc group buffer */
int *alloc)
{
xfs_agi_t *agi; /* allocation group header */
xfs_alloc_arg_t args; /* allocation argument structure */
xfs_agnumber_t agno;
int error;
xfs_agino_t newino; /* new first inode's number */
xfs_agino_t newlen; /* new number of inodes */
int isaligned = 0; /* inode allocation at stripe unit */
/* boundary */
struct xfs_perag *pag;
memset(&args, 0, sizeof(args));
args.tp = tp;
args.mp = tp->t_mountp;
/*
* Locking will ensure that we don't have two callers in here
* at one time.
*/
newlen = args.mp->m_ialloc_inos;
if (args.mp->m_maxicount &&
args.mp->m_sb.sb_icount + newlen > args.mp->m_maxicount)
return -ENOSPC;
args.minlen = args.maxlen = args.mp->m_ialloc_blks;
/*
* First try to allocate inodes contiguous with the last-allocated
* chunk of inodes. If the filesystem is striped, this will fill
* an entire stripe unit with inodes.
*/
agi = XFS_BUF_TO_AGI(agbp);
newino = be32_to_cpu(agi->agi_newino);
agno = be32_to_cpu(agi->agi_seqno);
args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) +
args.mp->m_ialloc_blks;
if (likely(newino != NULLAGINO &&
(args.agbno < be32_to_cpu(agi->agi_length)))) {
args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
args.type = XFS_ALLOCTYPE_THIS_BNO;
args.prod = 1;
/*
* We need to take into account alignment here to ensure that
* we don't modify the free list if we fail to have an exact
* block. If we don't have an exact match, and every oher
* attempt allocation attempt fails, we'll end up cancelling
* a dirty transaction and shutting down.
*
* For an exact allocation, alignment must be 1,
* however we need to take cluster alignment into account when
* fixing up the freelist. Use the minalignslop field to
* indicate that extra blocks might be required for alignment,
* but not to use them in the actual exact allocation.
*/
args.alignment = 1;
args.minalignslop = xfs_ialloc_cluster_alignment(args.mp) - 1;
/* Allow space for the inode btree to split. */
args.minleft = args.mp->m_in_maxlevels - 1;
if ((error = xfs_alloc_vextent(&args)))
return error;
/*
* This request might have dirtied the transaction if the AG can
* satisfy the request, but the exact block was not available.
* If the allocation did fail, subsequent requests will relax
* the exact agbno requirement and increase the alignment
* instead. It is critical that the total size of the request
* (len + alignment + slop) does not increase from this point
* on, so reset minalignslop to ensure it is not included in
* subsequent requests.
*/
args.minalignslop = 0;
} else
args.fsbno = NULLFSBLOCK;
if (unlikely(args.fsbno == NULLFSBLOCK)) {
/*
* Set the alignment for the allocation.
* If stripe alignment is turned on then align at stripe unit
* boundary.
* If the cluster size is smaller than a filesystem block
* then we're doing I/O for inodes in filesystem block size
* pieces, so don't need alignment anyway.
*/
isaligned = 0;
if (args.mp->m_sinoalign) {
ASSERT(!(args.mp->m_flags & XFS_MOUNT_NOALIGN));
args.alignment = args.mp->m_dalign;
isaligned = 1;
} else
args.alignment = xfs_ialloc_cluster_alignment(args.mp);
/*
* Need to figure out where to allocate the inode blocks.
* Ideally they should be spaced out through the a.g.
* For now, just allocate blocks up front.
*/
args.agbno = be32_to_cpu(agi->agi_root);
args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
/*
* Allocate a fixed-size extent of inodes.
*/
args.type = XFS_ALLOCTYPE_NEAR_BNO;
args.prod = 1;
/*
* Allow space for the inode btree to split.
*/
args.minleft = args.mp->m_in_maxlevels - 1;
if ((error = xfs_alloc_vextent(&args)))
return error;
}
/*
* If stripe alignment is turned on, then try again with cluster
* alignment.
*/
if (isaligned && args.fsbno == NULLFSBLOCK) {
args.type = XFS_ALLOCTYPE_NEAR_BNO;
args.agbno = be32_to_cpu(agi->agi_root);
args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
args.alignment = xfs_ialloc_cluster_alignment(args.mp);
if ((error = xfs_alloc_vextent(&args)))
return error;
}
if (args.fsbno == NULLFSBLOCK) {
*alloc = 0;
return 0;
}
ASSERT(args.len == args.minlen);
/*
* Stamp and write the inode buffers.
*
* Seed the new inode cluster with a random generation number. This
* prevents short-term reuse of generation numbers if a chunk is
* freed and then immediately reallocated. We use random numbers
* rather than a linear progression to prevent the next generation
* number from being easily guessable.
*/
error = xfs_ialloc_inode_init(args.mp, tp, NULL, agno, args.agbno,
args.len, prandom_u32());
if (error)
return error;
/*
* Convert the results.
*/
newino = XFS_OFFBNO_TO_AGINO(args.mp, args.agbno, 0);
be32_add_cpu(&agi->agi_count, newlen);
be32_add_cpu(&agi->agi_freecount, newlen);
pag = xfs_perag_get(args.mp, agno);
pag->pagi_freecount += newlen;
xfs_perag_put(pag);
agi->agi_newino = cpu_to_be32(newino);
/*
* Insert records describing the new inode chunk into the btrees.
*/
error = xfs_inobt_insert(args.mp, tp, agbp, newino, newlen,
XFS_BTNUM_INO);
if (error)
return error;
if (xfs_sb_version_hasfinobt(&args.mp->m_sb)) {
error = xfs_inobt_insert(args.mp, tp, agbp, newino, newlen,
XFS_BTNUM_FINO);
if (error)
return error;
}
/*
* Log allocation group header fields
*/
xfs_ialloc_log_agi(tp, agbp,
XFS_AGI_COUNT | XFS_AGI_FREECOUNT | XFS_AGI_NEWINO);
/*
* Modify/log superblock values for inode count and inode free count.
*/
xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, (long)newlen);
xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, (long)newlen);
*alloc = 1;
return 0;
}
STATIC xfs_agnumber_t
xfs_ialloc_next_ag(
xfs_mount_t *mp)
{
xfs_agnumber_t agno;
spin_lock(&mp->m_agirotor_lock);
agno = mp->m_agirotor;
if (++mp->m_agirotor >= mp->m_maxagi)
mp->m_agirotor = 0;
spin_unlock(&mp->m_agirotor_lock);
return agno;
}
/*
* Select an allocation group to look for a free inode in, based on the parent
* inode and the mode. Return the allocation group buffer.
*/
STATIC xfs_agnumber_t
xfs_ialloc_ag_select(
xfs_trans_t *tp, /* transaction pointer */
xfs_ino_t parent, /* parent directory inode number */
umode_t mode, /* bits set to indicate file type */
int okalloc) /* ok to allocate more space */
{
xfs_agnumber_t agcount; /* number of ag's in the filesystem */
xfs_agnumber_t agno; /* current ag number */
int flags; /* alloc buffer locking flags */
xfs_extlen_t ineed; /* blocks needed for inode allocation */
xfs_extlen_t longest = 0; /* longest extent available */
xfs_mount_t *mp; /* mount point structure */
int needspace; /* file mode implies space allocated */
xfs_perag_t *pag; /* per allocation group data */
xfs_agnumber_t pagno; /* parent (starting) ag number */
int error;
/*
* Files of these types need at least one block if length > 0
* (and they won't fit in the inode, but that's hard to figure out).
*/
needspace = S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode);
mp = tp->t_mountp;
agcount = mp->m_maxagi;
if (S_ISDIR(mode))
pagno = xfs_ialloc_next_ag(mp);
else {
pagno = XFS_INO_TO_AGNO(mp, parent);
if (pagno >= agcount)
pagno = 0;
}
ASSERT(pagno < agcount);
/*
* Loop through allocation groups, looking for one with a little
* free space in it. Note we don't look for free inodes, exactly.
* Instead, we include whether there is a need to allocate inodes
* to mean that blocks must be allocated for them,
* if none are currently free.
*/
agno = pagno;
flags = XFS_ALLOC_FLAG_TRYLOCK;
for (;;) {
pag = xfs_perag_get(mp, agno);
if (!pag->pagi_inodeok) {
xfs_ialloc_next_ag(mp);
goto nextag;
}
if (!pag->pagi_init) {
error = xfs_ialloc_pagi_init(mp, tp, agno);
if (error)
goto nextag;
}
if (pag->pagi_freecount) {
xfs_perag_put(pag);
return agno;
}
if (!okalloc)
goto nextag;
if (!pag->pagf_init) {
error = xfs_alloc_pagf_init(mp, tp, agno, flags);
if (error)
goto nextag;
}
/*
* Check that there is enough free space for the file plus a
* chunk of inodes if we need to allocate some. If this is the
* first pass across the AGs, take into account the potential
* space needed for alignment of inode chunks when checking the
* longest contiguous free space in the AG - this prevents us
* from getting ENOSPC because we have free space larger than
* m_ialloc_blks but alignment constraints prevent us from using
* it.
*
* If we can't find an AG with space for full alignment slack to
* be taken into account, we must be near ENOSPC in all AGs.
* Hence we don't include alignment for the second pass and so
* if we fail allocation due to alignment issues then it is most
* likely a real ENOSPC condition.
*/
ineed = mp->m_ialloc_blks;
if (flags && ineed > 1)
ineed += xfs_ialloc_cluster_alignment(mp);
longest = pag->pagf_longest;
if (!longest)
longest = pag->pagf_flcount > 0;
if (pag->pagf_freeblks >= needspace + ineed &&
longest >= ineed) {
xfs_perag_put(pag);
return agno;
}
nextag:
xfs_perag_put(pag);
/*
* No point in iterating over the rest, if we're shutting
* down.
*/
if (XFS_FORCED_SHUTDOWN(mp))
return NULLAGNUMBER;
agno++;
if (agno >= agcount)
agno = 0;
if (agno == pagno) {
if (flags == 0)
return NULLAGNUMBER;
flags = 0;
}
}
}
/*
* Try to retrieve the next record to the left/right from the current one.
*/
STATIC int
xfs_ialloc_next_rec(
struct xfs_btree_cur *cur,
xfs_inobt_rec_incore_t *rec,
int *done,
int left)
{
int error;
int i;
if (left)
error = xfs_btree_decrement(cur, 0, &i);
else
error = xfs_btree_increment(cur, 0, &i);
if (error)
return error;
*done = !i;
if (i) {
error = xfs_inobt_get_rec(cur, rec, &i);
if (error)
return error;
XFS_WANT_CORRUPTED_RETURN(i == 1);
}
return 0;
}
STATIC int
xfs_ialloc_get_rec(
struct xfs_btree_cur *cur,
xfs_agino_t agino,
xfs_inobt_rec_incore_t *rec,
int *done)
{
int error;
int i;
error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_EQ, &i);
if (error)
return error;
*done = !i;
if (i) {
error = xfs_inobt_get_rec(cur, rec, &i);
if (error)
return error;
XFS_WANT_CORRUPTED_RETURN(i == 1);
}
return 0;
}
/*
* Allocate an inode using the inobt-only algorithm.
*/
STATIC int
xfs_dialloc_ag_inobt(
struct xfs_trans *tp,
struct xfs_buf *agbp,
xfs_ino_t parent,
xfs_ino_t *inop)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
xfs_agnumber_t pagno = XFS_INO_TO_AGNO(mp, parent);
xfs_agino_t pagino = XFS_INO_TO_AGINO(mp, parent);
struct xfs_perag *pag;
struct xfs_btree_cur *cur, *tcur;
struct xfs_inobt_rec_incore rec, trec;
xfs_ino_t ino;
int error;
int offset;
int i, j;
pag = xfs_perag_get(mp, agno);
ASSERT(pag->pagi_init);
ASSERT(pag->pagi_inodeok);
ASSERT(pag->pagi_freecount > 0);
restart_pagno:
cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO);
/*
* If pagino is 0 (this is the root inode allocation) use newino.
* This must work because we've just allocated some.
*/
if (!pagino)
pagino = be32_to_cpu(agi->agi_newino);
error = xfs_check_agi_freecount(cur, agi);
if (error)
goto error0;
/*
* If in the same AG as the parent, try to get near the parent.
*/
if (pagno == agno) {
int doneleft; /* done, to the left */
int doneright; /* done, to the right */
int searchdistance = 10;
error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i);
if (error)
goto error0;
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
error = xfs_inobt_get_rec(cur, &rec, &j);
if (error)
goto error0;
XFS_WANT_CORRUPTED_GOTO(j == 1, error0);
if (rec.ir_freecount > 0) {
/*
* Found a free inode in the same chunk
* as the parent, done.
*/
goto alloc_inode;
}
/*
* In the same AG as parent, but parent's chunk is full.
*/
/* duplicate the cursor, search left & right simultaneously */
error = xfs_btree_dup_cursor(cur, &tcur);
if (error)
goto error0;
/*
* Skip to last blocks looked up if same parent inode.
*/
if (pagino != NULLAGINO &&
pag->pagl_pagino == pagino &&
pag->pagl_leftrec != NULLAGINO &&
pag->pagl_rightrec != NULLAGINO) {
error = xfs_ialloc_get_rec(tcur, pag->pagl_leftrec,
&trec, &doneleft);
if (error)
goto error1;
error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec,
&rec, &doneright);
if (error)
goto error1;
} else {
/* search left with tcur, back up 1 record */
error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1);
if (error)
goto error1;
/* search right with cur, go forward 1 record. */
error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0);
if (error)
goto error1;
}
/*
* Loop until we find an inode chunk with a free inode.
*/
while (!doneleft || !doneright) {
int useleft; /* using left inode chunk this time */
if (!--searchdistance) {
/*
* Not in range - save last search
* location and allocate a new inode
*/
xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
pag->pagl_leftrec = trec.ir_startino;
pag->pagl_rightrec = rec.ir_startino;
pag->pagl_pagino = pagino;
goto newino;
}
/* figure out the closer block if both are valid. */
if (!doneleft && !doneright) {
useleft = pagino -
(trec.ir_startino + XFS_INODES_PER_CHUNK - 1) <
rec.ir_startino - pagino;
} else {
useleft = !doneleft;
}
/* free inodes to the left? */
if (useleft && trec.ir_freecount) {
rec = trec;
xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
cur = tcur;
pag->pagl_leftrec = trec.ir_startino;
pag->pagl_rightrec = rec.ir_startino;
pag->pagl_pagino = pagino;
goto alloc_inode;
}
/* free inodes to the right? */
if (!useleft && rec.ir_freecount) {
xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
pag->pagl_leftrec = trec.ir_startino;
pag->pagl_rightrec = rec.ir_startino;
pag->pagl_pagino = pagino;
goto alloc_inode;
}
/* get next record to check */
if (useleft) {
error = xfs_ialloc_next_rec(tcur, &trec,
&doneleft, 1);
} else {
error = xfs_ialloc_next_rec(cur, &rec,
&doneright, 0);
}
if (error)
goto error1;
}
/*
* We've reached the end of the btree. because
* we are only searching a small chunk of the
* btree each search, there is obviously free
* inodes closer to the parent inode than we
* are now. restart the search again.
*/
pag->pagl_pagino = NULLAGINO;
pag->pagl_leftrec = NULLAGINO;
pag->pagl_rightrec = NULLAGINO;
xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
goto restart_pagno;
}
/*
* In a different AG from the parent.
* See if the most recently allocated block has any free.
*/
newino:
if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
XFS_LOOKUP_EQ, &i);
if (error)
goto error0;
if (i == 1) {
error = xfs_inobt_get_rec(cur, &rec, &j);
if (error)
goto error0;
if (j == 1 && rec.ir_freecount > 0) {
/*
* The last chunk allocated in the group
* still has a free inode.
*/
goto alloc_inode;
}
}
}
/*
* None left in the last group, search the whole AG
*/
error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
if (error)
goto error0;
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
for (;;) {
error = xfs_inobt_get_rec(cur, &rec, &i);
if (error)
goto error0;
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
if (rec.ir_freecount > 0)
break;
error = xfs_btree_increment(cur, 0, &i);
if (error)
goto error0;
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
}
alloc_inode:
offset = xfs_lowbit64(rec.ir_free);
ASSERT(offset >= 0);
ASSERT(offset < XFS_INODES_PER_CHUNK);
ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
XFS_INODES_PER_CHUNK) == 0);
ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino + offset);
rec.ir_free &= ~XFS_INOBT_MASK(offset);
rec.ir_freecount--;
error = xfs_inobt_update(cur, &rec);
if (error)
goto error0;
be32_add_cpu(&agi->agi_freecount, -1);
xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
pag->pagi_freecount--;
error = xfs_check_agi_freecount(cur, agi);
if (error)
goto error0;
xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
xfs_perag_put(pag);
*inop = ino;
return 0;
error1:
xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
error0:
xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
xfs_perag_put(pag);
return error;
}
/*
* Use the free inode btree to allocate an inode based on distance from the
* parent. Note that the provided cursor may be deleted and replaced.
*/
STATIC int
xfs_dialloc_ag_finobt_near(
xfs_agino_t pagino,
struct xfs_btree_cur **ocur,
struct xfs_inobt_rec_incore *rec)
{
struct xfs_btree_cur *lcur = *ocur; /* left search cursor */
struct xfs_btree_cur *rcur; /* right search cursor */
struct xfs_inobt_rec_incore rrec;
int error;
int i, j;
error = xfs_inobt_lookup(lcur, pagino, XFS_LOOKUP_LE, &i);
if (error)
return error;
if (i == 1) {
error = xfs_inobt_get_rec(lcur, rec, &i);
if (error)
return error;
XFS_WANT_CORRUPTED_RETURN(i == 1);
/*
* See if we've landed in the parent inode record. The finobt
* only tracks chunks with at least one free inode, so record
* existence is enough.
*/
if (pagino >= rec->ir_startino &&
pagino < (rec->ir_startino + XFS_INODES_PER_CHUNK))
return 0;
}
error = xfs_btree_dup_cursor(lcur, &rcur);
if (error)
return error;
error = xfs_inobt_lookup(rcur, pagino, XFS_LOOKUP_GE, &j);
if (error)
goto error_rcur;
if (j == 1) {
error = xfs_inobt_get_rec(rcur, &rrec, &j);
if (error)
goto error_rcur;
XFS_WANT_CORRUPTED_GOTO(j == 1, error_rcur);
}
XFS_WANT_CORRUPTED_GOTO(i == 1 || j == 1, error_rcur);
if (i == 1 && j == 1) {
/*
* Both the left and right records are valid. Choose the closer
* inode chunk to the target.
*/
if ((pagino - rec->ir_startino + XFS_INODES_PER_CHUNK - 1) >
(rrec.ir_startino - pagino)) {
*rec = rrec;
xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
*ocur = rcur;
} else {
xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
}
} else if (j == 1) {
/* only the right record is valid */
*rec = rrec;
xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
*ocur = rcur;
} else if (i == 1) {
/* only the left record is valid */
xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
}
return 0;
error_rcur:
xfs_btree_del_cursor(rcur, XFS_BTREE_ERROR);
return error;
}
/*
* Use the free inode btree to find a free inode based on a newino hint. If
* the hint is NULL, find the first free inode in the AG.
*/
STATIC int
xfs_dialloc_ag_finobt_newino(
struct xfs_agi *agi,
struct xfs_btree_cur *cur,
struct xfs_inobt_rec_incore *rec)
{
int error;
int i;
if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
XFS_LOOKUP_EQ, &i);
if (error)
return error;
if (i == 1) {
error = xfs_inobt_get_rec(cur, rec, &i);
if (error)
return error;
XFS_WANT_CORRUPTED_RETURN(i == 1);
return 0;
}
}
/*
* Find the first inode available in the AG.
*/
error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
if (error)
return error;
XFS_WANT_CORRUPTED_RETURN(i == 1);
error = xfs_inobt_get_rec(cur, rec, &i);
if (error)
return error;
XFS_WANT_CORRUPTED_RETURN(i == 1);
return 0;
}
/*
* Update the inobt based on a modification made to the finobt. Also ensure that
* the records from both trees are equivalent post-modification.
*/
STATIC int
xfs_dialloc_ag_update_inobt(
struct xfs_btree_cur *cur, /* inobt cursor */
struct xfs_inobt_rec_incore *frec, /* finobt record */
int offset) /* inode offset */
{
struct xfs_inobt_rec_incore rec;
int error;
int i;
error = xfs_inobt_lookup(cur, frec->ir_startino, XFS_LOOKUP_EQ, &i);
if (error)
return error;
XFS_WANT_CORRUPTED_RETURN(i == 1);
error = xfs_inobt_get_rec(cur, &rec, &i);
if (error)
return error;
XFS_WANT_CORRUPTED_RETURN(i == 1);
ASSERT((XFS_AGINO_TO_OFFSET(cur->bc_mp, rec.ir_startino) %
XFS_INODES_PER_CHUNK) == 0);
rec.ir_free &= ~XFS_INOBT_MASK(offset);
rec.ir_freecount--;
XFS_WANT_CORRUPTED_RETURN((rec.ir_free == frec->ir_free) &&
(rec.ir_freecount == frec->ir_freecount));
return xfs_inobt_update(cur, &rec);
}
/*
* Allocate an inode using the free inode btree, if available. Otherwise, fall
* back to the inobt search algorithm.
*
* The caller selected an AG for us, and made sure that free inodes are
* available.
*/
STATIC int
xfs_dialloc_ag(
struct xfs_trans *tp,
struct xfs_buf *agbp,
xfs_ino_t parent,
xfs_ino_t *inop)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
xfs_agnumber_t pagno = XFS_INO_TO_AGNO(mp, parent);
xfs_agino_t pagino = XFS_INO_TO_AGINO(mp, parent);
struct xfs_perag *pag;
struct xfs_btree_cur *cur; /* finobt cursor */
struct xfs_btree_cur *icur; /* inobt cursor */
struct xfs_inobt_rec_incore rec;
xfs_ino_t ino;
int error;
int offset;
int i;
if (!xfs_sb_version_hasfinobt(&mp->m_sb))
return xfs_dialloc_ag_inobt(tp, agbp, parent, inop);
pag = xfs_perag_get(mp, agno);
/*
* If pagino is 0 (this is the root inode allocation) use newino.
* This must work because we've just allocated some.
*/
if (!pagino)
pagino = be32_to_cpu(agi->agi_newino);
cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_FINO);
error = xfs_check_agi_freecount(cur, agi);
if (error)
goto error_cur;
/*
* The search algorithm depends on whether we're in the same AG as the
* parent. If so, find the closest available inode to the parent. If
* not, consider the agi hint or find the first free inode in the AG.
*/
if (agno == pagno)
error = xfs_dialloc_ag_finobt_near(pagino, &cur, &rec);
else
error = xfs_dialloc_ag_finobt_newino(agi, cur, &rec);
if (error)
goto error_cur;
offset = xfs_lowbit64(rec.ir_free);
ASSERT(offset >= 0);
ASSERT(offset < XFS_INODES_PER_CHUNK);
ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
XFS_INODES_PER_CHUNK) == 0);
ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino + offset);
/*
* Modify or remove the finobt record.
*/
rec.ir_free &= ~XFS_INOBT_MASK(offset);
rec.ir_freecount--;
if (rec.ir_freecount)
error = xfs_inobt_update(cur, &rec);
else
error = xfs_btree_delete(cur, &i);
if (error)
goto error_cur;
/*
* The finobt has now been updated appropriately. We haven't updated the
* agi and superblock yet, so we can create an inobt cursor and validate
* the original freecount. If all is well, make the equivalent update to
* the inobt using the finobt record and offset information.
*/
icur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO);
error = xfs_check_agi_freecount(icur, agi);
if (error)
goto error_icur;
error = xfs_dialloc_ag_update_inobt(icur, &rec, offset);
if (error)
goto error_icur;
/*
* Both trees have now been updated. We must update the perag and
* superblock before we can check the freecount for each btree.
*/
be32_add_cpu(&agi->agi_freecount, -1);
xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
pag->pagi_freecount--;
xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
error = xfs_check_agi_freecount(icur, agi);
if (error)
goto error_icur;
error = xfs_check_agi_freecount(cur, agi);
if (error)
goto error_icur;
xfs_btree_del_cursor(icur, XFS_BTREE_NOERROR);
xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
xfs_perag_put(pag);
*inop = ino;
return 0;
error_icur:
xfs_btree_del_cursor(icur, XFS_BTREE_ERROR);
error_cur:
xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
xfs_perag_put(pag);
return error;
}
/*
* Allocate an inode on disk.
*
* Mode is used to tell whether the new inode will need space, and whether it
* is a directory.
*
* This function is designed to be called twice if it has to do an allocation
* to make more free inodes. On the first call, *IO_agbp should be set to NULL.
* If an inode is available without having to performn an allocation, an inode
* number is returned. In this case, *IO_agbp is set to NULL. If an allocation
* needs to be done, xfs_dialloc returns the current AGI buffer in *IO_agbp.
* The caller should then commit the current transaction, allocate a
* new transaction, and call xfs_dialloc() again, passing in the previous value
* of *IO_agbp. IO_agbp should be held across the transactions. Since the AGI
* buffer is locked across the two calls, the second call is guaranteed to have
* a free inode available.
*
* Once we successfully pick an inode its number is returned and the on-disk
* data structures are updated. The inode itself is not read in, since doing so
* would break ordering constraints with xfs_reclaim.
*/
int
xfs_dialloc(
struct xfs_trans *tp,
xfs_ino_t parent,
umode_t mode,
int okalloc,
struct xfs_buf **IO_agbp,
xfs_ino_t *inop)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_buf *agbp;
xfs_agnumber_t agno;
int error;
int ialloced;
int noroom = 0;
xfs_agnumber_t start_agno;
struct xfs_perag *pag;
if (*IO_agbp) {
/*
* If the caller passes in a pointer to the AGI buffer,
* continue where we left off before. In this case, we
* know that the allocation group has free inodes.
*/
agbp = *IO_agbp;
goto out_alloc;
}
/*
* We do not have an agbp, so select an initial allocation
* group for inode allocation.
*/
start_agno = xfs_ialloc_ag_select(tp, parent, mode, okalloc);
if (start_agno == NULLAGNUMBER) {
*inop = NULLFSINO;
return 0;
}
/*
* If we have already hit the ceiling of inode blocks then clear
* okalloc so we scan all available agi structures for a free
* inode.
*/
if (mp->m_maxicount &&
mp->m_sb.sb_icount + mp->m_ialloc_inos > mp->m_maxicount) {
noroom = 1;
okalloc = 0;
}
/*
* Loop until we find an allocation group that either has free inodes
* or in which we can allocate some inodes. Iterate through the
* allocation groups upward, wrapping at the end.
*/
agno = start_agno;
for (;;) {
pag = xfs_perag_get(mp, agno);
if (!pag->pagi_inodeok) {
xfs_ialloc_next_ag(mp);
goto nextag;
}
if (!pag->pagi_init) {
error = xfs_ialloc_pagi_init(mp, tp, agno);
if (error)
goto out_error;
}
/*
* Do a first racy fast path check if this AG is usable.
*/
if (!pag->pagi_freecount && !okalloc)
goto nextag;
/*
* Then read in the AGI buffer and recheck with the AGI buffer
* lock held.
*/
error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
if (error)
goto out_error;
if (pag->pagi_freecount) {
xfs_perag_put(pag);
goto out_alloc;
}
if (!okalloc)
goto nextag_relse_buffer;
error = xfs_ialloc_ag_alloc(tp, agbp, &ialloced);
if (error) {
xfs_trans_brelse(tp, agbp);
if (error != -ENOSPC)
goto out_error;
xfs_perag_put(pag);
*inop = NULLFSINO;
return 0;
}
if (ialloced) {
/*
* We successfully allocated some inodes, return
* the current context to the caller so that it
* can commit the current transaction and call
* us again where we left off.
*/
ASSERT(pag->pagi_freecount > 0);
xfs_perag_put(pag);
*IO_agbp = agbp;
*inop = NULLFSINO;
return 0;
}
nextag_relse_buffer:
xfs_trans_brelse(tp, agbp);
nextag:
xfs_perag_put(pag);
if (++agno == mp->m_sb.sb_agcount)
agno = 0;
if (agno == start_agno) {
*inop = NULLFSINO;
return noroom ? -ENOSPC : 0;
}
}
out_alloc:
*IO_agbp = NULL;
return xfs_dialloc_ag(tp, agbp, parent, inop);
out_error:
xfs_perag_put(pag);
return error;
}
STATIC int
xfs_difree_inobt(
struct xfs_mount *mp,
struct xfs_trans *tp,
struct xfs_buf *agbp,
xfs_agino_t agino,
struct xfs_bmap_free *flist,
int *deleted,
xfs_ino_t *first_ino,
struct xfs_inobt_rec_incore *orec)
{
struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
struct xfs_perag *pag;
struct xfs_btree_cur *cur;
struct xfs_inobt_rec_incore rec;
int ilen;
int error;
int i;
int off;
ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
ASSERT(XFS_AGINO_TO_AGBNO(mp, agino) < be32_to_cpu(agi->agi_length));
/*
* Initialize the cursor.
*/
cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO);
error = xfs_check_agi_freecount(cur, agi);
if (error)
goto error0;
/*
* Look for the entry describing this inode.
*/
if ((error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i))) {
xfs_warn(mp, "%s: xfs_inobt_lookup() returned error %d.",
__func__, error);
goto error0;
}
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
error = xfs_inobt_get_rec(cur, &rec, &i);
if (error) {
xfs_warn(mp, "%s: xfs_inobt_get_rec() returned error %d.",
__func__, error);
goto error0;
}
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
/*
* Get the offset in the inode chunk.
*/
off = agino - rec.ir_startino;
ASSERT(off >= 0 && off < XFS_INODES_PER_CHUNK);
ASSERT(!(rec.ir_free & XFS_INOBT_MASK(off)));
/*
* Mark the inode free & increment the count.
*/
rec.ir_free |= XFS_INOBT_MASK(off);
rec.ir_freecount++;
/*
* When an inode cluster is free, it becomes eligible for removal
*/
if (!(mp->m_flags & XFS_MOUNT_IKEEP) &&
(rec.ir_freecount == mp->m_ialloc_inos)) {
*deleted = 1;
*first_ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino);
/*
* Remove the inode cluster from the AGI B+Tree, adjust the
* AGI and Superblock inode counts, and mark the disk space
* to be freed when the transaction is committed.
*/
ilen = mp->m_ialloc_inos;
be32_add_cpu(&agi->agi_count, -ilen);
be32_add_cpu(&agi->agi_freecount, -(ilen - 1));
xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT);
pag = xfs_perag_get(mp, agno);
pag->pagi_freecount -= ilen - 1;
xfs_perag_put(pag);
xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen);
xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1));
if ((error = xfs_btree_delete(cur, &i))) {
xfs_warn(mp, "%s: xfs_btree_delete returned error %d.",
__func__, error);
goto error0;
}
xfs_bmap_add_free(XFS_AGB_TO_FSB(mp, agno,
XFS_AGINO_TO_AGBNO(mp, rec.ir_startino)),
mp->m_ialloc_blks, flist, mp);
} else {
*deleted = 0;
error = xfs_inobt_update(cur, &rec);
if (error) {
xfs_warn(mp, "%s: xfs_inobt_update returned error %d.",
__func__, error);
goto error0;
}
/*
* Change the inode free counts and log the ag/sb changes.
*/
be32_add_cpu(&agi->agi_freecount, 1);
xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
pag = xfs_perag_get(mp, agno);
pag->pagi_freecount++;
xfs_perag_put(pag);
xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, 1);
}
error = xfs_check_agi_freecount(cur, agi);
if (error)
goto error0;
*orec = rec;
xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
return 0;
error0:
xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
return error;
}
/*
* Free an inode in the free inode btree.
*/
STATIC int
xfs_difree_finobt(
struct xfs_mount *mp,
struct xfs_trans *tp,
struct xfs_buf *agbp,
xfs_agino_t agino,
struct xfs_inobt_rec_incore *ibtrec) /* inobt record */
{
struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
struct xfs_btree_cur *cur;
struct xfs_inobt_rec_incore rec;
int offset = agino - ibtrec->ir_startino;
int error;
int i;
cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_FINO);
error = xfs_inobt_lookup(cur, ibtrec->ir_startino, XFS_LOOKUP_EQ, &i);
if (error)
goto error;
if (i == 0) {
/*
* If the record does not exist in the finobt, we must have just
* freed an inode in a previously fully allocated chunk. If not,
* something is out of sync.
*/
XFS_WANT_CORRUPTED_GOTO(ibtrec->ir_freecount == 1, error);
error = xfs_inobt_insert_rec(cur, ibtrec->ir_freecount,
ibtrec->ir_free, &i);
if (error)
goto error;
ASSERT(i == 1);
goto out;
}
/*
* Read and update the existing record. We could just copy the ibtrec
* across here, but that would defeat the purpose of having redundant
* metadata. By making the modifications independently, we can catch
* corruptions that we wouldn't see if we just copied from one record
* to another.
*/
error = xfs_inobt_get_rec(cur, &rec, &i);
if (error)
goto error;
XFS_WANT_CORRUPTED_GOTO(i == 1, error);
rec.ir_free |= XFS_INOBT_MASK(offset);
rec.ir_freecount++;
XFS_WANT_CORRUPTED_GOTO((rec.ir_free == ibtrec->ir_free) &&
(rec.ir_freecount == ibtrec->ir_freecount),
error);
/*
* The content of inobt records should always match between the inobt
* and finobt. The lifecycle of records in the finobt is different from
* the inobt in that the finobt only tracks records with at least one
* free inode. Hence, if all of the inodes are free and we aren't
* keeping inode chunks permanently on disk, remove the record.
* Otherwise, update the record with the new information.
*/
if (rec.ir_freecount == mp->m_ialloc_inos &&
!(mp->m_flags & XFS_MOUNT_IKEEP)) {
error = xfs_btree_delete(cur, &i);
if (error)
goto error;
ASSERT(i == 1);
} else {
error = xfs_inobt_update(cur, &rec);
if (error)
goto error;
}
out:
error = xfs_check_agi_freecount(cur, agi);
if (error)
goto error;
xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
return 0;
error:
xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
return error;
}
/*
* Free disk inode. Carefully avoids touching the incore inode, all
* manipulations incore are the caller's responsibility.
* The on-disk inode is not changed by this operation, only the
* btree (free inode mask) is changed.
*/
int
xfs_difree(
struct xfs_trans *tp, /* transaction pointer */
xfs_ino_t inode, /* inode to be freed */
struct xfs_bmap_free *flist, /* extents to free */
int *deleted,/* set if inode cluster was deleted */
xfs_ino_t *first_ino)/* first inode in deleted cluster */
{
/* REFERENCED */
xfs_agblock_t agbno; /* block number containing inode */
struct xfs_buf *agbp; /* buffer for allocation group header */
xfs_agino_t agino; /* allocation group inode number */
xfs_agnumber_t agno; /* allocation group number */
int error; /* error return value */
struct xfs_mount *mp; /* mount structure for filesystem */
struct xfs_inobt_rec_incore rec;/* btree record */
mp = tp->t_mountp;
/*
* Break up inode number into its components.
*/
agno = XFS_INO_TO_AGNO(mp, inode);
if (agno >= mp->m_sb.sb_agcount) {
xfs_warn(mp, "%s: agno >= mp->m_sb.sb_agcount (%d >= %d).",
__func__, agno, mp->m_sb.sb_agcount);
ASSERT(0);
return -EINVAL;
}
agino = XFS_INO_TO_AGINO(mp, inode);
if (inode != XFS_AGINO_TO_INO(mp, agno, agino)) {
xfs_warn(mp, "%s: inode != XFS_AGINO_TO_INO() (%llu != %llu).",
__func__, (unsigned long long)inode,
(unsigned long long)XFS_AGINO_TO_INO(mp, agno, agino));
ASSERT(0);
return -EINVAL;
}
agbno = XFS_AGINO_TO_AGBNO(mp, agino);
if (agbno >= mp->m_sb.sb_agblocks) {
xfs_warn(mp, "%s: agbno >= mp->m_sb.sb_agblocks (%d >= %d).",
__func__, agbno, mp->m_sb.sb_agblocks);
ASSERT(0);
return -EINVAL;
}
/*
* Get the allocation group header.
*/
error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
if (error) {
xfs_warn(mp, "%s: xfs_ialloc_read_agi() returned error %d.",
__func__, error);
return error;
}
/*
* Fix up the inode allocation btree.
*/
error = xfs_difree_inobt(mp, tp, agbp, agino, flist, deleted, first_ino,
&rec);
if (error)
goto error0;
/*
* Fix up the free inode btree.
*/
if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
error = xfs_difree_finobt(mp, tp, agbp, agino, &rec);
if (error)
goto error0;
}
return 0;
error0:
return error;
}
STATIC int
xfs_imap_lookup(
struct xfs_mount *mp,
struct xfs_trans *tp,
xfs_agnumber_t agno,
xfs_agino_t agino,
xfs_agblock_t agbno,
xfs_agblock_t *chunk_agbno,
xfs_agblock_t *offset_agbno,
int flags)
{
struct xfs_inobt_rec_incore rec;
struct xfs_btree_cur *cur;
struct xfs_buf *agbp;
int error;
int i;
error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
if (error) {
xfs_alert(mp,
"%s: xfs_ialloc_read_agi() returned error %d, agno %d",
__func__, error, agno);
return error;
}
/*
* Lookup the inode record for the given agino. If the record cannot be
* found, then it's an invalid inode number and we should abort. Once
* we have a record, we need to ensure it contains the inode number
* we are looking up.
*/
cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO);
error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i);
if (!error) {
if (i)
error = xfs_inobt_get_rec(cur, &rec, &i);
if (!error && i == 0)
error = -EINVAL;
}
xfs_trans_brelse(tp, agbp);
xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
if (error)
return error;
/* check that the returned record contains the required inode */
if (rec.ir_startino > agino ||
rec.ir_startino + mp->m_ialloc_inos <= agino)
return -EINVAL;
/* for untrusted inodes check it is allocated first */
if ((flags & XFS_IGET_UNTRUSTED) &&
(rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino)))
return -EINVAL;
*chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino);
*offset_agbno = agbno - *chunk_agbno;
return 0;
}
/*
* Return the location of the inode in imap, for mapping it into a buffer.
*/
int
xfs_imap(
xfs_mount_t *mp, /* file system mount structure */
xfs_trans_t *tp, /* transaction pointer */
xfs_ino_t ino, /* inode to locate */
struct xfs_imap *imap, /* location map structure */
uint flags) /* flags for inode btree lookup */
{
xfs_agblock_t agbno; /* block number of inode in the alloc group */
xfs_agino_t agino; /* inode number within alloc group */
xfs_agnumber_t agno; /* allocation group number */
int blks_per_cluster; /* num blocks per inode cluster */
xfs_agblock_t chunk_agbno; /* first block in inode chunk */
xfs_agblock_t cluster_agbno; /* first block in inode cluster */
int error; /* error code */
int offset; /* index of inode in its buffer */
xfs_agblock_t offset_agbno; /* blks from chunk start to inode */
ASSERT(ino != NULLFSINO);
/*
* Split up the inode number into its parts.
*/
agno = XFS_INO_TO_AGNO(mp, ino);
agino = XFS_INO_TO_AGINO(mp, ino);
agbno = XFS_AGINO_TO_AGBNO(mp, agino);
if (agno >= mp->m_sb.sb_agcount || agbno >= mp->m_sb.sb_agblocks ||
ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
#ifdef DEBUG
/*
* Don't output diagnostic information for untrusted inodes
* as they can be invalid without implying corruption.
*/
if (flags & XFS_IGET_UNTRUSTED)
return -EINVAL;
if (agno >= mp->m_sb.sb_agcount) {
xfs_alert(mp,
"%s: agno (%d) >= mp->m_sb.sb_agcount (%d)",
__func__, agno, mp->m_sb.sb_agcount);
}
if (agbno >= mp->m_sb.sb_agblocks) {
xfs_alert(mp,
"%s: agbno (0x%llx) >= mp->m_sb.sb_agblocks (0x%lx)",
__func__, (unsigned long long)agbno,
(unsigned long)mp->m_sb.sb_agblocks);
}
if (ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
xfs_alert(mp,
"%s: ino (0x%llx) != XFS_AGINO_TO_INO() (0x%llx)",
__func__, ino,
XFS_AGINO_TO_INO(mp, agno, agino));
}
xfs_stack_trace();
#endif /* DEBUG */
return -EINVAL;
}
blks_per_cluster = xfs_icluster_size_fsb(mp);
/*
* For bulkstat and handle lookups, we have an untrusted inode number
* that we have to verify is valid. We cannot do this just by reading
* the inode buffer as it may have been unlinked and removed leaving
* inodes in stale state on disk. Hence we have to do a btree lookup
* in all cases where an untrusted inode number is passed.
*/
if (flags & XFS_IGET_UNTRUSTED) {
error = xfs_imap_lookup(mp, tp, agno, agino, agbno,
&chunk_agbno, &offset_agbno, flags);
if (error)
return error;
goto out_map;
}
/*
* If the inode cluster size is the same as the blocksize or
* smaller we get to the buffer by simple arithmetics.
*/
if (blks_per_cluster == 1) {
offset = XFS_INO_TO_OFFSET(mp, ino);
ASSERT(offset < mp->m_sb.sb_inopblock);
imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, agbno);
imap->im_len = XFS_FSB_TO_BB(mp, 1);
imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
return 0;
}
/*
* If the inode chunks are aligned then use simple maths to
* find the location. Otherwise we have to do a btree
* lookup to find the location.
*/
if (mp->m_inoalign_mask) {
offset_agbno = agbno & mp->m_inoalign_mask;
chunk_agbno = agbno - offset_agbno;
} else {
error = xfs_imap_lookup(mp, tp, agno, agino, agbno,
&chunk_agbno, &offset_agbno, flags);
if (error)
return error;
}
out_map:
ASSERT(agbno >= chunk_agbno);
cluster_agbno = chunk_agbno +
((offset_agbno / blks_per_cluster) * blks_per_cluster);
offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
XFS_INO_TO_OFFSET(mp, ino);
imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, cluster_agbno);
imap->im_len = XFS_FSB_TO_BB(mp, blks_per_cluster);
imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
/*
* If the inode number maps to a block outside the bounds
* of the file system then return NULL rather than calling
* read_buf and panicing when we get an error from the
* driver.
*/
if ((imap->im_blkno + imap->im_len) >
XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
xfs_alert(mp,
"%s: (im_blkno (0x%llx) + im_len (0x%llx)) > sb_dblocks (0x%llx)",
__func__, (unsigned long long) imap->im_blkno,
(unsigned long long) imap->im_len,
XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
return -EINVAL;
}
return 0;
}
/*
* Compute and fill in value of m_in_maxlevels.
*/
void
xfs_ialloc_compute_maxlevels(
xfs_mount_t *mp) /* file system mount structure */
{
int level;
uint maxblocks;
uint maxleafents;
int minleafrecs;
int minnoderecs;
maxleafents = (1LL << XFS_INO_AGINO_BITS(mp)) >>
XFS_INODES_PER_CHUNK_LOG;
minleafrecs = mp->m_alloc_mnr[0];
minnoderecs = mp->m_alloc_mnr[1];
maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
for (level = 1; maxblocks > 1; level++)
maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs;
mp->m_in_maxlevels = level;
}
/*
* Log specified fields for the ag hdr (inode section). The growth of the agi
* structure over time requires that we interpret the buffer as two logical
* regions delineated by the end of the unlinked list. This is due to the size
* of the hash table and its location in the middle of the agi.
*
* For example, a request to log a field before agi_unlinked and a field after
* agi_unlinked could cause us to log the entire hash table and use an excessive
* amount of log space. To avoid this behavior, log the region up through
* agi_unlinked in one call and the region after agi_unlinked through the end of
* the structure in another.
*/
void
xfs_ialloc_log_agi(
xfs_trans_t *tp, /* transaction pointer */
xfs_buf_t *bp, /* allocation group header buffer */
int fields) /* bitmask of fields to log */
{
int first; /* first byte number */
int last; /* last byte number */
static const short offsets[] = { /* field starting offsets */
/* keep in sync with bit definitions */
offsetof(xfs_agi_t, agi_magicnum),
offsetof(xfs_agi_t, agi_versionnum),
offsetof(xfs_agi_t, agi_seqno),
offsetof(xfs_agi_t, agi_length),
offsetof(xfs_agi_t, agi_count),
offsetof(xfs_agi_t, agi_root),
offsetof(xfs_agi_t, agi_level),
offsetof(xfs_agi_t, agi_freecount),
offsetof(xfs_agi_t, agi_newino),
offsetof(xfs_agi_t, agi_dirino),
offsetof(xfs_agi_t, agi_unlinked),
offsetof(xfs_agi_t, agi_free_root),
offsetof(xfs_agi_t, agi_free_level),
sizeof(xfs_agi_t)
};
#ifdef DEBUG
xfs_agi_t *agi; /* allocation group header */
agi = XFS_BUF_TO_AGI(bp);
ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
#endif
xfs_trans_buf_set_type(tp, bp, XFS_BLFT_AGI_BUF);
/*
* Compute byte offsets for the first and last fields in the first
* region and log the agi buffer. This only logs up through
* agi_unlinked.
*/
if (fields & XFS_AGI_ALL_BITS_R1) {
xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R1,
&first, &last);
xfs_trans_log_buf(tp, bp, first, last);
}
/*
* Mask off the bits in the first region and calculate the first and
* last field offsets for any bits in the second region.
*/
fields &= ~XFS_AGI_ALL_BITS_R1;
if (fields) {
xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R2,
&first, &last);
xfs_trans_log_buf(tp, bp, first, last);
}
}
#ifdef DEBUG
STATIC void
xfs_check_agi_unlinked(
struct xfs_agi *agi)
{
int i;
for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++)
ASSERT(agi->agi_unlinked[i]);
}
#else
#define xfs_check_agi_unlinked(agi)
#endif
static bool
xfs_agi_verify(
struct xfs_buf *bp)
{
struct xfs_mount *mp = bp->b_target->bt_mount;
struct xfs_agi *agi = XFS_BUF_TO_AGI(bp);
if (xfs_sb_version_hascrc(&mp->m_sb) &&
!uuid_equal(&agi->agi_uuid, &mp->m_sb.sb_uuid))
return false;
/*
* Validate the magic number of the agi block.
*/
if (agi->agi_magicnum != cpu_to_be32(XFS_AGI_MAGIC))
return false;
if (!XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)))
return false;
if (be32_to_cpu(agi->agi_level) > XFS_BTREE_MAXLEVELS)
return false;
/*
* during growfs operations, the perag is not fully initialised,
* so we can't use it for any useful checking. growfs ensures we can't
* use it by using uncached buffers that don't have the perag attached
* so we can detect and avoid this problem.
*/
if (bp->b_pag && be32_to_cpu(agi->agi_seqno) != bp->b_pag->pag_agno)
return false;
xfs_check_agi_unlinked(agi);
return true;
}
static void
xfs_agi_read_verify(
struct xfs_buf *bp)
{
struct xfs_mount *mp = bp->b_target->bt_mount;
if (xfs_sb_version_hascrc(&mp->m_sb) &&
!xfs_buf_verify_cksum(bp, XFS_AGI_CRC_OFF))
xfs_buf_ioerror(bp, -EFSBADCRC);
else if (XFS_TEST_ERROR(!xfs_agi_verify(bp), mp,
XFS_ERRTAG_IALLOC_READ_AGI,
XFS_RANDOM_IALLOC_READ_AGI))
xfs_buf_ioerror(bp, -EFSCORRUPTED);
if (bp->b_error)
xfs_verifier_error(bp);
}
static void
xfs_agi_write_verify(
struct xfs_buf *bp)
{
struct xfs_mount *mp = bp->b_target->bt_mount;
struct xfs_buf_log_item *bip = bp->b_fspriv;
if (!xfs_agi_verify(bp)) {
xfs_buf_ioerror(bp, -EFSCORRUPTED);
xfs_verifier_error(bp);
return;
}
if (!xfs_sb_version_hascrc(&mp->m_sb))
return;
if (bip)
XFS_BUF_TO_AGI(bp)->agi_lsn = cpu_to_be64(bip->bli_item.li_lsn);
xfs_buf_update_cksum(bp, XFS_AGI_CRC_OFF);
}
const struct xfs_buf_ops xfs_agi_buf_ops = {
.verify_read = xfs_agi_read_verify,
.verify_write = xfs_agi_write_verify,
};
/*
* Read in the allocation group header (inode allocation section)
*/
int
xfs_read_agi(
struct xfs_mount *mp, /* file system mount structure */
struct xfs_trans *tp, /* transaction pointer */
xfs_agnumber_t agno, /* allocation group number */
struct xfs_buf **bpp) /* allocation group hdr buf */
{
int error;
trace_xfs_read_agi(mp, agno);
ASSERT(agno != NULLAGNUMBER);
error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
XFS_FSS_TO_BB(mp, 1), 0, bpp, &xfs_agi_buf_ops);
if (error)
return error;
xfs_buf_set_ref(*bpp, XFS_AGI_REF);
return 0;
}
int
xfs_ialloc_read_agi(
struct xfs_mount *mp, /* file system mount structure */
struct xfs_trans *tp, /* transaction pointer */
xfs_agnumber_t agno, /* allocation group number */
struct xfs_buf **bpp) /* allocation group hdr buf */
{
struct xfs_agi *agi; /* allocation group header */
struct xfs_perag *pag; /* per allocation group data */
int error;
trace_xfs_ialloc_read_agi(mp, agno);
error = xfs_read_agi(mp, tp, agno, bpp);
if (error)
return error;
agi = XFS_BUF_TO_AGI(*bpp);
pag = xfs_perag_get(mp, agno);
if (!pag->pagi_init) {
pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
pag->pagi_count = be32_to_cpu(agi->agi_count);
pag->pagi_init = 1;
}
/*
* It's possible for these to be out of sync if
* we are in the middle of a forced shutdown.
*/
ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
XFS_FORCED_SHUTDOWN(mp));
xfs_perag_put(pag);
return 0;
}
/*
* Read in the agi to initialise the per-ag data in the mount structure
*/
int
xfs_ialloc_pagi_init(
xfs_mount_t *mp, /* file system mount structure */
xfs_trans_t *tp, /* transaction pointer */
xfs_agnumber_t agno) /* allocation group number */
{
xfs_buf_t *bp = NULL;
int error;
error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
if (error)
return error;
if (bp)
xfs_trans_brelse(tp, bp);
return 0;
}