zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/fs/xfs/xfs_fsops.c b/ap/os/linux/linux-3.4.x/fs/xfs/xfs_fsops.c
new file mode 100644
index 0000000..1c6fdeb
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/xfs/xfs_fsops.c
@@ -0,0 +1,695 @@
+/*
+ * 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_types.h"
+#include "xfs_bit.h"
+#include "xfs_inum.h"
+#include "xfs_log.h"
+#include "xfs_trans.h"
+#include "xfs_sb.h"
+#include "xfs_ag.h"
+#include "xfs_mount.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_alloc_btree.h"
+#include "xfs_ialloc_btree.h"
+#include "xfs_dinode.h"
+#include "xfs_inode.h"
+#include "xfs_inode_item.h"
+#include "xfs_btree.h"
+#include "xfs_error.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_rw.h"
+#include "xfs_filestream.h"
+#include "xfs_trace.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);
+ 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 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;
+ xfs_agi_t *agi;
+ xfs_agnumber_t agno;
+ xfs_extlen_t agsize;
+ xfs_extlen_t tmpsize;
+ xfs_alloc_rec_t *arec;
+ struct xfs_btree_block *block;
+ xfs_buf_t *bp;
+ int bucket;
+ int dpct;
+ int error;
+ 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, mp->m_ddev_targp,
+ XFS_FSB_TO_BB(mp, nb) - XFS_FSS_TO_BB(mp, 1),
+ BBTOB(XFS_FSS_TO_BB(mp, 1)), 0);
+ if (!bp)
+ return EIO;
+ 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;
+ if ((error = xfs_trans_reserve(tp, XFS_GROWFS_SPACE_RES(mp),
+ XFS_GROWDATA_LOG_RES(mp), 0, 0, 0))) {
+ 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) {
+ /*
+ * AG freelist header block
+ */
+ bp = xfs_buf_get(mp->m_ddev_targp,
+ XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
+ XFS_FSS_TO_BB(mp, 1), XBF_LOCK | XBF_MAPPED);
+ if (!bp) {
+ error = ENOMEM;
+ goto error0;
+ }
+ agf = XFS_BUF_TO_AGF(bp);
+ memset(agf, 0, mp->m_sb.sb_sectsize);
+ 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);
+ error = xfs_bwrite(bp);
+ xfs_buf_relse(bp);
+ if (error)
+ goto error0;
+
+ /*
+ * AG inode header block
+ */
+ bp = xfs_buf_get(mp->m_ddev_targp,
+ XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
+ XFS_FSS_TO_BB(mp, 1), XBF_LOCK | XBF_MAPPED);
+ if (!bp) {
+ error = ENOMEM;
+ goto error0;
+ }
+ agi = XFS_BUF_TO_AGI(bp);
+ memset(agi, 0, mp->m_sb.sb_sectsize);
+ 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);
+ 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_buf_get(mp->m_ddev_targp,
+ XFS_AGB_TO_DADDR(mp, agno, XFS_BNO_BLOCK(mp)),
+ BTOBB(mp->m_sb.sb_blocksize),
+ XBF_LOCK | XBF_MAPPED);
+ if (!bp) {
+ error = ENOMEM;
+ goto error0;
+ }
+ block = XFS_BUF_TO_BLOCK(bp);
+ memset(block, 0, mp->m_sb.sb_blocksize);
+ block->bb_magic = cpu_to_be32(XFS_ABTB_MAGIC);
+ block->bb_level = 0;
+ block->bb_numrecs = cpu_to_be16(1);
+ block->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
+ block->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
+ arec = XFS_ALLOC_REC_ADDR(mp, block, 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_buf_get(mp->m_ddev_targp,
+ XFS_AGB_TO_DADDR(mp, agno, XFS_CNT_BLOCK(mp)),
+ BTOBB(mp->m_sb.sb_blocksize),
+ XBF_LOCK | XBF_MAPPED);
+ if (!bp) {
+ error = ENOMEM;
+ goto error0;
+ }
+ block = XFS_BUF_TO_BLOCK(bp);
+ memset(block, 0, mp->m_sb.sb_blocksize);
+ block->bb_magic = cpu_to_be32(XFS_ABTC_MAGIC);
+ block->bb_level = 0;
+ block->bb_numrecs = cpu_to_be16(1);
+ block->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
+ block->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
+ arec = XFS_ALLOC_REC_ADDR(mp, block, 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_buf_get(mp->m_ddev_targp,
+ XFS_AGB_TO_DADDR(mp, agno, XFS_IBT_BLOCK(mp)),
+ BTOBB(mp->m_sb.sb_blocksize),
+ XBF_LOCK | XBF_MAPPED);
+ if (!bp) {
+ error = ENOMEM;
+ goto error0;
+ }
+ block = XFS_BUF_TO_BLOCK(bp);
+ memset(block, 0, mp->m_sb.sb_blocksize);
+ block->bb_magic = cpu_to_be32(XFS_IBT_MAGIC);
+ block->bb_level = 0;
+ block->bb_numrecs = 0;
+ block->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
+ block->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
+ 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 = xfs_read_buf(mp, mp->m_ddev_targp,
+ XFS_AGB_TO_DADDR(mp, agno, XFS_SB_BLOCK(mp)),
+ XFS_FSS_TO_BB(mp, 1), 0, &bp);
+ if (error) {
+ xfs_warn(mp,
+ "error %d reading secondary superblock for ag %d",
+ error, agno);
+ break;
+ }
+ xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb, XFS_SB_ALL_BITS);
+ /*
+ * If we get an error writing out the alternate superblocks,
+ * just issue a warning and continue. The real work is
+ * already done and committed.
+ */
+ error = xfs_bwrite(bp);
+ xfs_buf_relse(bp);
+ if (error) {
+ xfs_warn(mp,
+ "write error %d updating secondary superblock for ag %d",
+ error, agno);
+ break; /* no point in continuing */
+ }
+ }
+ return 0;
+
+ 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, 0, mp->m_sb.sb_sectsize + 128, 0, 0,
+ XFS_DEFAULT_LOG_COUNT);
+ 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;
+}