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linux/fs/xfs/xfs_fsops.c
Dave Chinner b7d961b35b xfs: growfs overruns AGFL buffer on V4 filesystems 
This loop in xfs_growfs_data_private() is incorrect for V4
superblocks filesystems:

		for (bucket = 0; bucket < XFS_AGFL_SIZE(mp); bucket++)
			agfl->agfl_bno[bucket] = cpu_to_be32(NULLAGBLOCK);

For V4 filesystems, we don't have a agfl header structure, and so
XFS_AGFL_SIZE() returns an entire sector's worth of entries, which
we then index from an offset into the sector. Hence: buffer overrun.

This problem was introduced in 3.10 by commit 77c95bba ("xfs: add
CRC checks to the AGFL") which changed the AGFL structure but failed
to update the growfs code to handle the different structures.

Fix it by using the correct offset into the buffer for both V4 and
V5 filesystems.

Cc: <stable@vger.kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-12-05 16:19:51 -06:00

855 lines
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/*
* Copyright (c) 2000-2005 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_sb.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_trans.h"
#include "xfs_inode_item.h"
#include "xfs_error.h"
#include "xfs_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_alloc.h"
#include "xfs_ialloc.h"
#include "xfs_fsops.h"
#include "xfs_itable.h"
#include "xfs_trans_space.h"
#include "xfs_rtalloc.h"
#include "xfs_trace.h"
#include "xfs_log.h"
#include "xfs_dinode.h"
#include "xfs_filestream.h"
/*
* File system operations
*/
int
xfs_fs_geometry(
xfs_mount_t *mp,
xfs_fsop_geom_t *geo,
int new_version)
{
memset(geo, 0, sizeof(*geo));
geo->blocksize = mp->m_sb.sb_blocksize;
geo->rtextsize = mp->m_sb.sb_rextsize;
geo->agblocks = mp->m_sb.sb_agblocks;
geo->agcount = mp->m_sb.sb_agcount;
geo->logblocks = mp->m_sb.sb_logblocks;
geo->sectsize = mp->m_sb.sb_sectsize;
geo->inodesize = mp->m_sb.sb_inodesize;
geo->imaxpct = mp->m_sb.sb_imax_pct;
geo->datablocks = mp->m_sb.sb_dblocks;
geo->rtblocks = mp->m_sb.sb_rblocks;
geo->rtextents = mp->m_sb.sb_rextents;
geo->logstart = mp->m_sb.sb_logstart;
ASSERT(sizeof(geo->uuid)==sizeof(mp->m_sb.sb_uuid));
memcpy(geo->uuid, &mp->m_sb.sb_uuid, sizeof(mp->m_sb.sb_uuid));
if (new_version >= 2) {
geo->sunit = mp->m_sb.sb_unit;
geo->swidth = mp->m_sb.sb_width;
}
if (new_version >= 3) {
geo->version = XFS_FSOP_GEOM_VERSION;
geo->flags =
(xfs_sb_version_hasattr(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_ATTR : 0) |
(xfs_sb_version_hasnlink(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_NLINK : 0) |
(xfs_sb_version_hasquota(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_QUOTA : 0) |
(xfs_sb_version_hasalign(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_IALIGN : 0) |
(xfs_sb_version_hasdalign(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_DALIGN : 0) |
(xfs_sb_version_hasshared(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_SHARED : 0) |
(xfs_sb_version_hasextflgbit(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_EXTFLG : 0) |
(xfs_sb_version_hasdirv2(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_DIRV2 : 0) |
(xfs_sb_version_hassector(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_SECTOR : 0) |
(xfs_sb_version_hasasciici(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_DIRV2CI : 0) |
(xfs_sb_version_haslazysbcount(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_LAZYSB : 0) |
(xfs_sb_version_hasattr2(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_ATTR2 : 0) |
(xfs_sb_version_hasprojid32bit(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_PROJID32 : 0) |
(xfs_sb_version_hascrc(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_V5SB : 0) |
(xfs_sb_version_hasftype(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_FTYPE : 0);
geo->logsectsize = xfs_sb_version_hassector(&mp->m_sb) ?
mp->m_sb.sb_logsectsize : BBSIZE;
geo->rtsectsize = mp->m_sb.sb_blocksize;
geo->dirblocksize = mp->m_dirblksize;
}
if (new_version >= 4) {
geo->flags |=
(xfs_sb_version_haslogv2(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_LOGV2 : 0);
geo->logsunit = mp->m_sb.sb_logsunit;
}
return 0;
}
static struct xfs_buf *
xfs_growfs_get_hdr_buf(
struct xfs_mount *mp,
xfs_daddr_t blkno,
size_t numblks,
int flags,
const struct xfs_buf_ops *ops)
{
struct xfs_buf *bp;
bp = xfs_buf_get_uncached(mp->m_ddev_targp, numblks, flags);
if (!bp)
return NULL;
xfs_buf_zero(bp, 0, BBTOB(bp->b_length));
bp->b_bn = blkno;
bp->b_maps[0].bm_bn = blkno;
bp->b_ops = ops;
return bp;
}
static int
xfs_growfs_data_private(
xfs_mount_t *mp, /* mount point for filesystem */
xfs_growfs_data_t *in) /* growfs data input struct */
{
xfs_agf_t *agf;
struct xfs_agfl *agfl;
xfs_agi_t *agi;
xfs_agnumber_t agno;
xfs_extlen_t agsize;
xfs_extlen_t tmpsize;
xfs_alloc_rec_t *arec;
xfs_buf_t *bp;
int bucket;
int dpct;
int error, saved_error = 0;
xfs_agnumber_t nagcount;
xfs_agnumber_t nagimax = 0;
xfs_rfsblock_t nb, nb_mod;
xfs_rfsblock_t new;
xfs_rfsblock_t nfree;
xfs_agnumber_t oagcount;
int pct;
xfs_trans_t *tp;
nb = in->newblocks;
pct = in->imaxpct;
if (nb < mp->m_sb.sb_dblocks || pct < 0 || pct > 100)
return XFS_ERROR(EINVAL);
if ((error = xfs_sb_validate_fsb_count(&mp->m_sb, nb)))
return error;
dpct = pct - mp->m_sb.sb_imax_pct;
bp = xfs_buf_read_uncached(mp->m_ddev_targp,
XFS_FSB_TO_BB(mp, nb) - XFS_FSS_TO_BB(mp, 1),
XFS_FSS_TO_BB(mp, 1), 0, NULL);
if (!bp)
return EIO;
if (bp->b_error) {
error = bp->b_error;
xfs_buf_relse(bp);
return error;
}
xfs_buf_relse(bp);
new = nb; /* use new as a temporary here */
nb_mod = do_div(new, mp->m_sb.sb_agblocks);
nagcount = new + (nb_mod != 0);
if (nb_mod && nb_mod < XFS_MIN_AG_BLOCKS) {
nagcount--;
nb = (xfs_rfsblock_t)nagcount * mp->m_sb.sb_agblocks;
if (nb < mp->m_sb.sb_dblocks)
return XFS_ERROR(EINVAL);
}
new = nb - mp->m_sb.sb_dblocks;
oagcount = mp->m_sb.sb_agcount;
/* allocate the new per-ag structures */
if (nagcount > oagcount) {
error = xfs_initialize_perag(mp, nagcount, &nagimax);
if (error)
return error;
}
tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFS);
tp->t_flags |= XFS_TRANS_RESERVE;
error = xfs_trans_reserve(tp, &M_RES(mp)->tr_growdata,
XFS_GROWFS_SPACE_RES(mp), 0);
if (error) {
xfs_trans_cancel(tp, 0);
return error;
}
/*
* Write new AG headers to disk. Non-transactional, but written
* synchronously so they are completed prior to the growfs transaction
* being logged.
*/
nfree = 0;
for (agno = nagcount - 1; agno >= oagcount; agno--, new -= agsize) {
__be32 *agfl_bno;
/*
* AG freespace header block
*/
bp = xfs_growfs_get_hdr_buf(mp,
XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
XFS_FSS_TO_BB(mp, 1), 0,
&xfs_agf_buf_ops);
if (!bp) {
error = ENOMEM;
goto error0;
}
agf = XFS_BUF_TO_AGF(bp);
agf->agf_magicnum = cpu_to_be32(XFS_AGF_MAGIC);
agf->agf_versionnum = cpu_to_be32(XFS_AGF_VERSION);
agf->agf_seqno = cpu_to_be32(agno);
if (agno == nagcount - 1)
agsize =
nb -
(agno * (xfs_rfsblock_t)mp->m_sb.sb_agblocks);
else
agsize = mp->m_sb.sb_agblocks;
agf->agf_length = cpu_to_be32(agsize);
agf->agf_roots[XFS_BTNUM_BNOi] = cpu_to_be32(XFS_BNO_BLOCK(mp));
agf->agf_roots[XFS_BTNUM_CNTi] = cpu_to_be32(XFS_CNT_BLOCK(mp));
agf->agf_levels[XFS_BTNUM_BNOi] = cpu_to_be32(1);
agf->agf_levels[XFS_BTNUM_CNTi] = cpu_to_be32(1);
agf->agf_flfirst = 0;
agf->agf_fllast = cpu_to_be32(XFS_AGFL_SIZE(mp) - 1);
agf->agf_flcount = 0;
tmpsize = agsize - XFS_PREALLOC_BLOCKS(mp);
agf->agf_freeblks = cpu_to_be32(tmpsize);
agf->agf_longest = cpu_to_be32(tmpsize);
if (xfs_sb_version_hascrc(&mp->m_sb))
uuid_copy(&agf->agf_uuid, &mp->m_sb.sb_uuid);
error = xfs_bwrite(bp);
xfs_buf_relse(bp);
if (error)
goto error0;
/*
* AG freelist header block
*/
bp = xfs_growfs_get_hdr_buf(mp,
XFS_AG_DADDR(mp, agno, XFS_AGFL_DADDR(mp)),
XFS_FSS_TO_BB(mp, 1), 0,
&xfs_agfl_buf_ops);
if (!bp) {
error = ENOMEM;
goto error0;
}
agfl = XFS_BUF_TO_AGFL(bp);
if (xfs_sb_version_hascrc(&mp->m_sb)) {
agfl->agfl_magicnum = cpu_to_be32(XFS_AGFL_MAGIC);
agfl->agfl_seqno = cpu_to_be32(agno);
uuid_copy(&agfl->agfl_uuid, &mp->m_sb.sb_uuid);
}
agfl_bno = XFS_BUF_TO_AGFL_BNO(mp, bp);
for (bucket = 0; bucket < XFS_AGFL_SIZE(mp); bucket++)
agfl_bno[bucket] = cpu_to_be32(NULLAGBLOCK);
error = xfs_bwrite(bp);
xfs_buf_relse(bp);
if (error)
goto error0;
/*
* AG inode header block
*/
bp = xfs_growfs_get_hdr_buf(mp,
XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
XFS_FSS_TO_BB(mp, 1), 0,
&xfs_agi_buf_ops);
if (!bp) {
error = ENOMEM;
goto error0;
}
agi = XFS_BUF_TO_AGI(bp);
agi->agi_magicnum = cpu_to_be32(XFS_AGI_MAGIC);
agi->agi_versionnum = cpu_to_be32(XFS_AGI_VERSION);
agi->agi_seqno = cpu_to_be32(agno);
agi->agi_length = cpu_to_be32(agsize);
agi->agi_count = 0;
agi->agi_root = cpu_to_be32(XFS_IBT_BLOCK(mp));
agi->agi_level = cpu_to_be32(1);
agi->agi_freecount = 0;
agi->agi_newino = cpu_to_be32(NULLAGINO);
agi->agi_dirino = cpu_to_be32(NULLAGINO);
if (xfs_sb_version_hascrc(&mp->m_sb))
uuid_copy(&agi->agi_uuid, &mp->m_sb.sb_uuid);
for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++)
agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
error = xfs_bwrite(bp);
xfs_buf_relse(bp);
if (error)
goto error0;
/*
* BNO btree root block
*/
bp = xfs_growfs_get_hdr_buf(mp,
XFS_AGB_TO_DADDR(mp, agno, XFS_BNO_BLOCK(mp)),
BTOBB(mp->m_sb.sb_blocksize), 0,
&xfs_allocbt_buf_ops);
if (!bp) {
error = ENOMEM;
goto error0;
}
if (xfs_sb_version_hascrc(&mp->m_sb))
xfs_btree_init_block(mp, bp, XFS_ABTB_CRC_MAGIC, 0, 1,
agno, XFS_BTREE_CRC_BLOCKS);
else
xfs_btree_init_block(mp, bp, XFS_ABTB_MAGIC, 0, 1,
agno, 0);
arec = XFS_ALLOC_REC_ADDR(mp, XFS_BUF_TO_BLOCK(bp), 1);
arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
arec->ar_blockcount = cpu_to_be32(
agsize - be32_to_cpu(arec->ar_startblock));
error = xfs_bwrite(bp);
xfs_buf_relse(bp);
if (error)
goto error0;
/*
* CNT btree root block
*/
bp = xfs_growfs_get_hdr_buf(mp,
XFS_AGB_TO_DADDR(mp, agno, XFS_CNT_BLOCK(mp)),
BTOBB(mp->m_sb.sb_blocksize), 0,
&xfs_allocbt_buf_ops);
if (!bp) {
error = ENOMEM;
goto error0;
}
if (xfs_sb_version_hascrc(&mp->m_sb))
xfs_btree_init_block(mp, bp, XFS_ABTC_CRC_MAGIC, 0, 1,
agno, XFS_BTREE_CRC_BLOCKS);
else
xfs_btree_init_block(mp, bp, XFS_ABTC_MAGIC, 0, 1,
agno, 0);
arec = XFS_ALLOC_REC_ADDR(mp, XFS_BUF_TO_BLOCK(bp), 1);
arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
arec->ar_blockcount = cpu_to_be32(
agsize - be32_to_cpu(arec->ar_startblock));
nfree += be32_to_cpu(arec->ar_blockcount);
error = xfs_bwrite(bp);
xfs_buf_relse(bp);
if (error)
goto error0;
/*
* INO btree root block
*/
bp = xfs_growfs_get_hdr_buf(mp,
XFS_AGB_TO_DADDR(mp, agno, XFS_IBT_BLOCK(mp)),
BTOBB(mp->m_sb.sb_blocksize), 0,
&xfs_inobt_buf_ops);
if (!bp) {
error = ENOMEM;
goto error0;
}
if (xfs_sb_version_hascrc(&mp->m_sb))
xfs_btree_init_block(mp, bp, XFS_IBT_CRC_MAGIC, 0, 0,
agno, XFS_BTREE_CRC_BLOCKS);
else
xfs_btree_init_block(mp, bp, XFS_IBT_MAGIC, 0, 0,
agno, 0);
error = xfs_bwrite(bp);
xfs_buf_relse(bp);
if (error)
goto error0;
}
xfs_trans_agblocks_delta(tp, nfree);
/*
* There are new blocks in the old last a.g.
*/
if (new) {
/*
* Change the agi length.
*/
error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
if (error) {
goto error0;
}
ASSERT(bp);
agi = XFS_BUF_TO_AGI(bp);
be32_add_cpu(&agi->agi_length, new);
ASSERT(nagcount == oagcount ||
be32_to_cpu(agi->agi_length) == mp->m_sb.sb_agblocks);
xfs_ialloc_log_agi(tp, bp, XFS_AGI_LENGTH);
/*
* Change agf length.
*/
error = xfs_alloc_read_agf(mp, tp, agno, 0, &bp);
if (error) {
goto error0;
}
ASSERT(bp);
agf = XFS_BUF_TO_AGF(bp);
be32_add_cpu(&agf->agf_length, new);
ASSERT(be32_to_cpu(agf->agf_length) ==
be32_to_cpu(agi->agi_length));
xfs_alloc_log_agf(tp, bp, XFS_AGF_LENGTH);
/*
* Free the new space.
*/
error = xfs_free_extent(tp, XFS_AGB_TO_FSB(mp, agno,
be32_to_cpu(agf->agf_length) - new), new);
if (error) {
goto error0;
}
}
/*
* Update changed superblock fields transactionally. These are not
* seen by the rest of the world until the transaction commit applies
* them atomically to the superblock.
*/
if (nagcount > oagcount)
xfs_trans_mod_sb(tp, XFS_TRANS_SB_AGCOUNT, nagcount - oagcount);
if (nb > mp->m_sb.sb_dblocks)
xfs_trans_mod_sb(tp, XFS_TRANS_SB_DBLOCKS,
nb - mp->m_sb.sb_dblocks);
if (nfree)
xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, nfree);
if (dpct)
xfs_trans_mod_sb(tp, XFS_TRANS_SB_IMAXPCT, dpct);
error = xfs_trans_commit(tp, 0);
if (error)
return error;
/* New allocation groups fully initialized, so update mount struct */
if (nagimax)
mp->m_maxagi = nagimax;
if (mp->m_sb.sb_imax_pct) {
__uint64_t icount = mp->m_sb.sb_dblocks * mp->m_sb.sb_imax_pct;
do_div(icount, 100);
mp->m_maxicount = icount << mp->m_sb.sb_inopblog;
} else
mp->m_maxicount = 0;
xfs_set_low_space_thresholds(mp);
/* update secondary superblocks. */
for (agno = 1; agno < nagcount; agno++) {
error = 0;
/*
* new secondary superblocks need to be zeroed, not read from
* disk as the contents of the new area we are growing into is
* completely unknown.
*/
if (agno < oagcount) {
error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp,
XFS_AGB_TO_DADDR(mp, agno, XFS_SB_BLOCK(mp)),
XFS_FSS_TO_BB(mp, 1), 0, &bp,
&xfs_sb_buf_ops);
} else {
bp = xfs_trans_get_buf(NULL, mp->m_ddev_targp,
XFS_AGB_TO_DADDR(mp, agno, XFS_SB_BLOCK(mp)),
XFS_FSS_TO_BB(mp, 1), 0);
if (bp) {
bp->b_ops = &xfs_sb_buf_ops;
xfs_buf_zero(bp, 0, BBTOB(bp->b_length));
} else
error = ENOMEM;
}
/*
* If we get an error reading or writing alternate superblocks,
* continue. xfs_repair chooses the "best" superblock based
* on most matches; if we break early, we'll leave more
* superblocks un-updated than updated, and xfs_repair may
* pick them over the properly-updated primary.
*/
if (error) {
xfs_warn(mp,
"error %d reading secondary superblock for ag %d",
error, agno);
saved_error = error;
continue;
}
xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb, XFS_SB_ALL_BITS);
error = xfs_bwrite(bp);
xfs_buf_relse(bp);
if (error) {
xfs_warn(mp,
"write error %d updating secondary superblock for ag %d",
error, agno);
saved_error = error;
continue;
}
}
return saved_error ? saved_error : error;
error0:
xfs_trans_cancel(tp, XFS_TRANS_ABORT);
return error;
}
static int
xfs_growfs_log_private(
xfs_mount_t *mp, /* mount point for filesystem */
xfs_growfs_log_t *in) /* growfs log input struct */
{
xfs_extlen_t nb;
nb = in->newblocks;
if (nb < XFS_MIN_LOG_BLOCKS || nb < XFS_B_TO_FSB(mp, XFS_MIN_LOG_BYTES))
return XFS_ERROR(EINVAL);
if (nb == mp->m_sb.sb_logblocks &&
in->isint == (mp->m_sb.sb_logstart != 0))
return XFS_ERROR(EINVAL);
/*
* Moving the log is hard, need new interfaces to sync
* the log first, hold off all activity while moving it.
* Can have shorter or longer log in the same space,
* or transform internal to external log or vice versa.
*/
return XFS_ERROR(ENOSYS);
}
/*
* protected versions of growfs function acquire and release locks on the mount
* point - exported through ioctls: XFS_IOC_FSGROWFSDATA, XFS_IOC_FSGROWFSLOG,
* XFS_IOC_FSGROWFSRT
*/
int
xfs_growfs_data(
xfs_mount_t *mp,
xfs_growfs_data_t *in)
{
int error;
if (!capable(CAP_SYS_ADMIN))
return XFS_ERROR(EPERM);
if (!mutex_trylock(&mp->m_growlock))
return XFS_ERROR(EWOULDBLOCK);
error = xfs_growfs_data_private(mp, in);
mutex_unlock(&mp->m_growlock);
return error;
}
int
xfs_growfs_log(
xfs_mount_t *mp,
xfs_growfs_log_t *in)
{
int error;
if (!capable(CAP_SYS_ADMIN))
return XFS_ERROR(EPERM);
if (!mutex_trylock(&mp->m_growlock))
return XFS_ERROR(EWOULDBLOCK);
error = xfs_growfs_log_private(mp, in);
mutex_unlock(&mp->m_growlock);
return error;
}
/*
* exported through ioctl XFS_IOC_FSCOUNTS
*/
int
xfs_fs_counts(
xfs_mount_t *mp,
xfs_fsop_counts_t *cnt)
{
xfs_icsb_sync_counters(mp, XFS_ICSB_LAZY_COUNT);
spin_lock(&mp->m_sb_lock);
cnt->freedata = mp->m_sb.sb_fdblocks - XFS_ALLOC_SET_ASIDE(mp);
cnt->freertx = mp->m_sb.sb_frextents;
cnt->freeino = mp->m_sb.sb_ifree;
cnt->allocino = mp->m_sb.sb_icount;
spin_unlock(&mp->m_sb_lock);
return 0;
}
/*
* exported through ioctl XFS_IOC_SET_RESBLKS & XFS_IOC_GET_RESBLKS
*
* xfs_reserve_blocks is called to set m_resblks
* in the in-core mount table. The number of unused reserved blocks
* is kept in m_resblks_avail.
*
* Reserve the requested number of blocks if available. Otherwise return
* as many as possible to satisfy the request. The actual number
* reserved are returned in outval
*
* A null inval pointer indicates that only the current reserved blocks
* available should be returned no settings are changed.
*/
int
xfs_reserve_blocks(
xfs_mount_t *mp,
__uint64_t *inval,
xfs_fsop_resblks_t *outval)
{
__int64_t lcounter, delta, fdblks_delta;
__uint64_t request;
/* If inval is null, report current values and return */
if (inval == (__uint64_t *)NULL) {
if (!outval)
return EINVAL;
outval->resblks = mp->m_resblks;
outval->resblks_avail = mp->m_resblks_avail;
return 0;
}
request = *inval;
/*
* With per-cpu counters, this becomes an interesting
* problem. we needto work out if we are freeing or allocation
* blocks first, then we can do the modification as necessary.
*
* We do this under the m_sb_lock so that if we are near
* ENOSPC, we will hold out any changes while we work out
* what to do. This means that the amount of free space can
* change while we do this, so we need to retry if we end up
* trying to reserve more space than is available.
*
* We also use the xfs_mod_incore_sb() interface so that we
* don't have to care about whether per cpu counter are
* enabled, disabled or even compiled in....
*/
retry:
spin_lock(&mp->m_sb_lock);
xfs_icsb_sync_counters_locked(mp, 0);
/*
* If our previous reservation was larger than the current value,
* then move any unused blocks back to the free pool.
*/
fdblks_delta = 0;
if (mp->m_resblks > request) {
lcounter = mp->m_resblks_avail - request;
if (lcounter > 0) { /* release unused blocks */
fdblks_delta = lcounter;
mp->m_resblks_avail -= lcounter;
}
mp->m_resblks = request;
} else {
__int64_t free;
free = mp->m_sb.sb_fdblocks - XFS_ALLOC_SET_ASIDE(mp);
if (!free)
goto out; /* ENOSPC and fdblks_delta = 0 */
delta = request - mp->m_resblks;
lcounter = free - delta;
if (lcounter < 0) {
/* We can't satisfy the request, just get what we can */
mp->m_resblks += free;
mp->m_resblks_avail += free;
fdblks_delta = -free;
} else {
fdblks_delta = -delta;
mp->m_resblks = request;
mp->m_resblks_avail += delta;
}
}
out:
if (outval) {
outval->resblks = mp->m_resblks;
outval->resblks_avail = mp->m_resblks_avail;
}
spin_unlock(&mp->m_sb_lock);
if (fdblks_delta) {
/*
* If we are putting blocks back here, m_resblks_avail is
* already at its max so this will put it in the free pool.
*
* If we need space, we'll either succeed in getting it
* from the free block count or we'll get an enospc. If
* we get a ENOSPC, it means things changed while we were
* calculating fdblks_delta and so we should try again to
* see if there is anything left to reserve.
*
* Don't set the reserved flag here - we don't want to reserve
* the extra reserve blocks from the reserve.....
*/
int error;
error = xfs_icsb_modify_counters(mp, XFS_SBS_FDBLOCKS,
fdblks_delta, 0);
if (error == ENOSPC)
goto retry;
}
return 0;
}
/*
* Dump a transaction into the log that contains no real change. This is needed
* to be able to make the log dirty or stamp the current tail LSN into the log
* during the covering operation.
*
* We cannot use an inode here for this - that will push dirty state back up
* into the VFS and then periodic inode flushing will prevent log covering from
* making progress. Hence we log a field in the superblock instead and use a
* synchronous transaction to ensure the superblock is immediately unpinned
* and can be written back.
*/
int
xfs_fs_log_dummy(
xfs_mount_t *mp)
{
xfs_trans_t *tp;
int error;
tp = _xfs_trans_alloc(mp, XFS_TRANS_DUMMY1, KM_SLEEP);
error = xfs_trans_reserve(tp, &M_RES(mp)->tr_sb, 0, 0);
if (error) {
xfs_trans_cancel(tp, 0);
return error;
}
/* log the UUID because it is an unchanging field */
xfs_mod_sb(tp, XFS_SB_UUID);
xfs_trans_set_sync(tp);
return xfs_trans_commit(tp, 0);
}
int
xfs_fs_goingdown(
xfs_mount_t *mp,
__uint32_t inflags)
{
switch (inflags) {
case XFS_FSOP_GOING_FLAGS_DEFAULT: {
struct super_block *sb = freeze_bdev(mp->m_super->s_bdev);
if (sb && !IS_ERR(sb)) {
xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
thaw_bdev(sb->s_bdev, sb);
}
break;
}
case XFS_FSOP_GOING_FLAGS_LOGFLUSH:
xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
break;
case XFS_FSOP_GOING_FLAGS_NOLOGFLUSH:
xfs_force_shutdown(mp,
SHUTDOWN_FORCE_UMOUNT | SHUTDOWN_LOG_IO_ERROR);
break;
default:
return XFS_ERROR(EINVAL);
}
return 0;
}
/*
* Force a shutdown of the filesystem instantly while keeping the filesystem
* consistent. We don't do an unmount here; just shutdown the shop, make sure
* that absolutely nothing persistent happens to this filesystem after this
* point.
*/
void
xfs_do_force_shutdown(
xfs_mount_t *mp,
int flags,
char *fname,
int lnnum)
{
int logerror;
logerror = flags & SHUTDOWN_LOG_IO_ERROR;
if (!(flags & SHUTDOWN_FORCE_UMOUNT)) {
xfs_notice(mp,
"%s(0x%x) called from line %d of file %s. Return address = 0x%p",
__func__, flags, lnnum, fname, __return_address);
}
/*
* No need to duplicate efforts.
*/
if (XFS_FORCED_SHUTDOWN(mp) && !logerror)
return;
/*
* This flags XFS_MOUNT_FS_SHUTDOWN, makes sure that we don't
* queue up anybody new on the log reservations, and wakes up
* everybody who's sleeping on log reservations to tell them
* the bad news.
*/
if (xfs_log_force_umount(mp, logerror))
return;
if (flags & SHUTDOWN_CORRUPT_INCORE) {
xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_CORRUPT,
"Corruption of in-memory data detected. Shutting down filesystem");
if (XFS_ERRLEVEL_HIGH <= xfs_error_level)
xfs_stack_trace();
} else if (!(flags & SHUTDOWN_FORCE_UMOUNT)) {
if (logerror) {
xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_LOGERROR,
"Log I/O Error Detected. Shutting down filesystem");
} else if (flags & SHUTDOWN_DEVICE_REQ) {
xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_IOERROR,
"All device paths lost. Shutting down filesystem");
} else if (!(flags & SHUTDOWN_REMOTE_REQ)) {
xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_IOERROR,
"I/O Error Detected. Shutting down filesystem");
}
}
if (!(flags & SHUTDOWN_FORCE_UMOUNT)) {
xfs_alert(mp,
"Please umount the filesystem and rectify the problem(s)");
}
}
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