swh:1:snp:c3bf2749e3476071fa748f67b0ffa2fdc5fe49d9
Tip revision: b562e44f507e863c6792946e4e1b1449fbbac85d authored by Linus Torvalds on 14 March 2016, 04:28:54 UTC
Linux 4.5
Linux 4.5
Tip revision: b562e44
xfs_fsops.c
/*
* 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_mount.h"
#include "xfs_da_format.h"
#include "xfs_da_btree.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_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_FSOP_GEOM_FLAGS_NLINK |
XFS_FSOP_GEOM_FLAGS_DIRV2 |
(xfs_sb_version_hasattr(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_ATTR : 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_hasextflgbit(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_EXTFLG : 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) |
(xfs_sb_version_hasfinobt(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_FINOBT : 0) |
(xfs_sb_version_hassparseinodes(&mp->m_sb) ?
XFS_FSOP_GEOM_FLAGS_SPINODES : 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_dir_geo->blksize;
}
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 -EINVAL;
if ((error = xfs_sb_validate_fsb_count(&mp->m_sb, nb)))
return error;
dpct = pct - mp->m_sb.sb_imax_pct;
error = 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, &bp, NULL);
if (error)
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 -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);
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_meta_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_meta_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_meta_uuid);
if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
agi->agi_free_root = cpu_to_be32(XFS_FIBT_BLOCK(mp));
agi->agi_free_level = cpu_to_be32(1);
}
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;
/*
* FINO btree root block
*/
if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
bp = xfs_growfs_get_hdr_buf(mp,
XFS_AGB_TO_DADDR(mp, agno, XFS_FIBT_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_FIBT_CRC_MAGIC,
0, 0, agno,
XFS_BTREE_CRC_BLOCKS);
else
xfs_btree_init_block(mp, bp, XFS_FIBT_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);
xfs_trans_set_sync(tp);
error = xfs_trans_commit(tp);
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);
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);
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 -EINVAL;
if (nb == mp->m_sb.sb_logblocks &&
in->isint == (mp->m_sb.sb_logstart != 0))
return -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 -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 -EPERM;
if (!mutex_trylock(&mp->m_growlock))
return -EWOULDBLOCK;
error = xfs_growfs_data_private(mp, in);
/*
* Increment the generation unconditionally, the error could be from
* updating the secondary superblocks, in which case the new size
* is live already.
*/
mp->m_generation++;
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 -EPERM;
if (!mutex_trylock(&mp->m_growlock))
return -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)
{
cnt->allocino = percpu_counter_read_positive(&mp->m_icount);
cnt->freeino = percpu_counter_read_positive(&mp->m_ifree);
cnt->freedata = percpu_counter_read_positive(&mp->m_fdblocks) -
XFS_ALLOC_SET_ASIDE(mp);
spin_lock(&mp->m_sb_lock);
cnt->freertx = mp->m_sb.sb_frextents;
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.
*/
retry:
spin_lock(&mp->m_sb_lock);
/*
* 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 = percpu_counter_sum(&mp->m_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_mod_fdblocks(mp, fdblks_delta, 0);
if (error == -ENOSPC)
goto retry;
}
return 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 -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)");
}
}