Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1586 insertions, 0 deletions

diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
new file mode 100644
index 0000000..b57423c
--- /dev/null
+++ b/fs/xfs/xfs_mount.c
@@ -0,0 +1,1586 @@
+/*
+ * Copyright (c) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 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.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like.  Any license provided herein, whether implied or
+ * otherwise, applies only to this software file.  Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA  94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
+ */
+
+#include "xfs.h"
+#include "xfs_macros.h"
+#include "xfs_types.h"
+#include "xfs_inum.h"
+#include "xfs_log.h"
+#include "xfs_trans.h"
+#include "xfs_sb.h"
+#include "xfs_ag.h"
+#include "xfs_dir.h"
+#include "xfs_dir2.h"
+#include "xfs_dmapi.h"
+#include "xfs_mount.h"
+#include "xfs_alloc_btree.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_ialloc_btree.h"
+#include "xfs_btree.h"
+#include "xfs_ialloc.h"
+#include "xfs_attr_sf.h"
+#include "xfs_dir_sf.h"
+#include "xfs_dir2_sf.h"
+#include "xfs_dinode.h"
+#include "xfs_inode.h"
+#include "xfs_alloc.h"
+#include "xfs_rtalloc.h"
+#include "xfs_bmap.h"
+#include "xfs_error.h"
+#include "xfs_bit.h"
+#include "xfs_rw.h"
+#include "xfs_quota.h"
+#include "xfs_fsops.h"
+
+STATIC void	xfs_mount_log_sbunit(xfs_mount_t *, __int64_t);
+STATIC int	xfs_uuid_mount(xfs_mount_t *);
+STATIC void	xfs_uuid_unmount(xfs_mount_t *mp);
+
+static struct {
+    short offset;
+    short type;     /* 0 = integer
+		* 1 = binary / string (no translation)
+		*/
+} xfs_sb_info[] = {
+    { offsetof(xfs_sb_t, sb_magicnum),   0 },
+    { offsetof(xfs_sb_t, sb_blocksize),  0 },
+    { offsetof(xfs_sb_t, sb_dblocks),    0 },
+    { offsetof(xfs_sb_t, sb_rblocks),    0 },
+    { offsetof(xfs_sb_t, sb_rextents),   0 },
+    { offsetof(xfs_sb_t, sb_uuid),       1 },
+    { offsetof(xfs_sb_t, sb_logstart),   0 },
+    { offsetof(xfs_sb_t, sb_rootino),    0 },
+    { offsetof(xfs_sb_t, sb_rbmino),     0 },
+    { offsetof(xfs_sb_t, sb_rsumino),    0 },
+    { offsetof(xfs_sb_t, sb_rextsize),   0 },
+    { offsetof(xfs_sb_t, sb_agblocks),   0 },
+    { offsetof(xfs_sb_t, sb_agcount),    0 },
+    { offsetof(xfs_sb_t, sb_rbmblocks),  0 },
+    { offsetof(xfs_sb_t, sb_logblocks),  0 },
+    { offsetof(xfs_sb_t, sb_versionnum), 0 },
+    { offsetof(xfs_sb_t, sb_sectsize),   0 },
+    { offsetof(xfs_sb_t, sb_inodesize),  0 },
+    { offsetof(xfs_sb_t, sb_inopblock),  0 },
+    { offsetof(xfs_sb_t, sb_fname[0]),   1 },
+    { offsetof(xfs_sb_t, sb_blocklog),   0 },
+    { offsetof(xfs_sb_t, sb_sectlog),    0 },
+    { offsetof(xfs_sb_t, sb_inodelog),   0 },
+    { offsetof(xfs_sb_t, sb_inopblog),   0 },
+    { offsetof(xfs_sb_t, sb_agblklog),   0 },
+    { offsetof(xfs_sb_t, sb_rextslog),   0 },
+    { offsetof(xfs_sb_t, sb_inprogress), 0 },
+    { offsetof(xfs_sb_t, sb_imax_pct),   0 },
+    { offsetof(xfs_sb_t, sb_icount),     0 },
+    { offsetof(xfs_sb_t, sb_ifree),      0 },
+    { offsetof(xfs_sb_t, sb_fdblocks),   0 },
+    { offsetof(xfs_sb_t, sb_frextents),  0 },
+    { offsetof(xfs_sb_t, sb_uquotino),   0 },
+    { offsetof(xfs_sb_t, sb_gquotino),   0 },
+    { offsetof(xfs_sb_t, sb_qflags),     0 },
+    { offsetof(xfs_sb_t, sb_flags),      0 },
+    { offsetof(xfs_sb_t, sb_shared_vn),  0 },
+    { offsetof(xfs_sb_t, sb_inoalignmt), 0 },
+    { offsetof(xfs_sb_t, sb_unit),	 0 },
+    { offsetof(xfs_sb_t, sb_width),	 0 },
+    { offsetof(xfs_sb_t, sb_dirblklog),	 0 },
+    { offsetof(xfs_sb_t, sb_logsectlog), 0 },
+    { offsetof(xfs_sb_t, sb_logsectsize),0 },
+    { offsetof(xfs_sb_t, sb_logsunit),	 0 },
+    { offsetof(xfs_sb_t, sb_features2),	 0 },
+    { sizeof(xfs_sb_t),			 0 }
+};
+
+/*
+ * Return a pointer to an initialized xfs_mount structure.
+ */
+xfs_mount_t *
+xfs_mount_init(void)
+{
+	xfs_mount_t *mp;
+
+	mp = kmem_zalloc(sizeof(*mp), KM_SLEEP);
+
+	AIL_LOCKINIT(&mp->m_ail_lock, "xfs_ail");
+	spinlock_init(&mp->m_sb_lock, "xfs_sb");
+	mutex_init(&mp->m_ilock, MUTEX_DEFAULT, "xfs_ilock");
+	initnsema(&mp->m_growlock, 1, "xfs_grow");
+	/*
+	 * Initialize the AIL.
+	 */
+	xfs_trans_ail_init(mp);
+
+	atomic_set(&mp->m_active_trans, 0);
+
+	return mp;
+}
+
+/*
+ * Free up the resources associated with a mount structure.  Assume that
+ * the structure was initially zeroed, so we can tell which fields got
+ * initialized.
+ */
+void
+xfs_mount_free(
+	xfs_mount_t *mp,
+	int	    remove_bhv)
+{
+	if (mp->m_ihash)
+		xfs_ihash_free(mp);
+	if (mp->m_chash)
+		xfs_chash_free(mp);
+
+	if (mp->m_perag) {
+		int	agno;
+
+		for (agno = 0; agno < mp->m_maxagi; agno++)
+			if (mp->m_perag[agno].pagb_list)
+				kmem_free(mp->m_perag[agno].pagb_list,
+						sizeof(xfs_perag_busy_t) *
+							XFS_PAGB_NUM_SLOTS);
+		kmem_free(mp->m_perag,
+			  sizeof(xfs_perag_t) * mp->m_sb.sb_agcount);
+	}
+
+	AIL_LOCK_DESTROY(&mp->m_ail_lock);
+	spinlock_destroy(&mp->m_sb_lock);
+	mutex_destroy(&mp->m_ilock);
+	freesema(&mp->m_growlock);
+	if (mp->m_quotainfo)
+		XFS_QM_DONE(mp);
+
+	if (mp->m_fsname != NULL)
+		kmem_free(mp->m_fsname, mp->m_fsname_len);
+
+	if (remove_bhv) {
+		struct vfs	*vfsp = XFS_MTOVFS(mp);
+
+		bhv_remove_all_vfsops(vfsp, 0);
+		VFS_REMOVEBHV(vfsp, &mp->m_bhv);
+	}
+
+	kmem_free(mp, sizeof(xfs_mount_t));
+}
+
+
+/*
+ * Check the validity of the SB found.
+ */
+STATIC int
+xfs_mount_validate_sb(
+	xfs_mount_t	*mp,
+	xfs_sb_t	*sbp)
+{
+	/*
+	 * If the log device and data device have the
+	 * same device number, the log is internal.
+	 * Consequently, the sb_logstart should be non-zero.  If
+	 * we have a zero sb_logstart in this case, we may be trying to mount
+	 * a volume filesystem in a non-volume manner.
+	 */
+	if (sbp->sb_magicnum != XFS_SB_MAGIC) {
+		cmn_err(CE_WARN, "XFS: bad magic number");
+		return XFS_ERROR(EWRONGFS);
+	}
+
+	if (!XFS_SB_GOOD_VERSION(sbp)) {
+		cmn_err(CE_WARN, "XFS: bad version");
+		return XFS_ERROR(EWRONGFS);
+	}
+
+	if (unlikely(
+	    sbp->sb_logstart == 0 && mp->m_logdev_targp == mp->m_ddev_targp)) {
+		cmn_err(CE_WARN,
+	"XFS: filesystem is marked as having an external log; "
+	"specify logdev on the\nmount command line.");
+		XFS_CORRUPTION_ERROR("xfs_mount_validate_sb(1)",
+				     XFS_ERRLEVEL_HIGH, mp, sbp);
+		return XFS_ERROR(EFSCORRUPTED);
+	}
+
+	if (unlikely(
+	    sbp->sb_logstart != 0 && mp->m_logdev_targp != mp->m_ddev_targp)) {
+		cmn_err(CE_WARN,
+	"XFS: filesystem is marked as having an internal log; "
+	"don't specify logdev on\nthe mount command line.");
+		XFS_CORRUPTION_ERROR("xfs_mount_validate_sb(2)",
+				     XFS_ERRLEVEL_HIGH, mp, sbp);
+		return XFS_ERROR(EFSCORRUPTED);
+	}
+
+	/*
+	 * More sanity checking. These were stolen directly from
+	 * xfs_repair.
+	 */
+	if (unlikely(
+	    sbp->sb_agcount <= 0					||
+	    sbp->sb_sectsize < XFS_MIN_SECTORSIZE			||
+	    sbp->sb_sectsize > XFS_MAX_SECTORSIZE			||
+	    sbp->sb_sectlog < XFS_MIN_SECTORSIZE_LOG			||
+	    sbp->sb_sectlog > XFS_MAX_SECTORSIZE_LOG			||
+	    sbp->sb_blocksize < XFS_MIN_BLOCKSIZE			||
+	    sbp->sb_blocksize > XFS_MAX_BLOCKSIZE			||
+	    sbp->sb_blocklog < XFS_MIN_BLOCKSIZE_LOG			||
+	    sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG			||
+	    sbp->sb_inodesize < XFS_DINODE_MIN_SIZE			||
+	    sbp->sb_inodesize > XFS_DINODE_MAX_SIZE			||
+	    (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE)	||
+	    (sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE)	||
+	    sbp->sb_imax_pct > 100)) {
+		cmn_err(CE_WARN, "XFS: SB sanity check 1 failed");
+		XFS_CORRUPTION_ERROR("xfs_mount_validate_sb(3)",
+				     XFS_ERRLEVEL_LOW, mp, sbp);
+		return XFS_ERROR(EFSCORRUPTED);
+	}
+
+	/*
+	 * Sanity check AG count, size fields against data size field
+	 */
+	if (unlikely(
+	    sbp->sb_dblocks == 0 ||
+	    sbp->sb_dblocks >
+	     (xfs_drfsbno_t)sbp->sb_agcount * sbp->sb_agblocks ||
+	    sbp->sb_dblocks < (xfs_drfsbno_t)(sbp->sb_agcount - 1) *
+			      sbp->sb_agblocks + XFS_MIN_AG_BLOCKS)) {
+		cmn_err(CE_WARN, "XFS: SB sanity check 2 failed");
+		XFS_ERROR_REPORT("xfs_mount_validate_sb(4)",
+				 XFS_ERRLEVEL_LOW, mp);
+		return XFS_ERROR(EFSCORRUPTED);
+	}
+
+	ASSERT(PAGE_SHIFT >= sbp->sb_blocklog);
+	ASSERT(sbp->sb_blocklog >= BBSHIFT);
+
+#if XFS_BIG_BLKNOS     /* Limited by ULONG_MAX of page cache index */
+	if (unlikely(
+	    (sbp->sb_dblocks >> (PAGE_SHIFT - sbp->sb_blocklog)) > ULONG_MAX ||
+	    (sbp->sb_rblocks >> (PAGE_SHIFT - sbp->sb_blocklog)) > ULONG_MAX)) {
+#else                  /* Limited by UINT_MAX of sectors */
+	if (unlikely(
+	    (sbp->sb_dblocks << (sbp->sb_blocklog - BBSHIFT)) > UINT_MAX ||
+	    (sbp->sb_rblocks << (sbp->sb_blocklog - BBSHIFT)) > UINT_MAX)) {
+#endif
+		cmn_err(CE_WARN,
+	"XFS: File system is too large to be mounted on this system.");
+		return XFS_ERROR(E2BIG);
+	}
+
+	if (unlikely(sbp->sb_inprogress)) {
+		cmn_err(CE_WARN, "XFS: file system busy");
+		XFS_ERROR_REPORT("xfs_mount_validate_sb(5)",
+				 XFS_ERRLEVEL_LOW, mp);
+		return XFS_ERROR(EFSCORRUPTED);
+	}
+
+	/*
+	 * Until this is fixed only page-sized or smaller data blocks work.
+	 */
+	if (unlikely(sbp->sb_blocksize > PAGE_SIZE)) {
+		cmn_err(CE_WARN,
+		"XFS: Attempted to mount file system with blocksize %d bytes",
+			sbp->sb_blocksize);
+		cmn_err(CE_WARN,
+		"XFS: Only page-sized (%d) or less blocksizes currently work.",
+			PAGE_SIZE);
+		return XFS_ERROR(ENOSYS);
+	}
+
+	return 0;
+}
+
+xfs_agnumber_t
+xfs_initialize_perag(xfs_mount_t *mp, xfs_agnumber_t agcount)
+{
+	xfs_agnumber_t	index, max_metadata;
+	xfs_perag_t	*pag;
+	xfs_agino_t	agino;
+	xfs_ino_t	ino;
+	xfs_sb_t	*sbp = &mp->m_sb;
+	xfs_ino_t	max_inum = XFS_MAXINUMBER_32;
+
+	/* Check to see if the filesystem can overflow 32 bit inodes */
+	agino = XFS_OFFBNO_TO_AGINO(mp, sbp->sb_agblocks - 1, 0);
+	ino = XFS_AGINO_TO_INO(mp, agcount - 1, agino);
+
+	/* Clear the mount flag if no inode can overflow 32 bits
+	 * on this filesystem, or if specifically requested..
+	 */
+	if ((mp->m_flags & XFS_MOUNT_32BITINOOPT) && ino > max_inum) {
+		mp->m_flags |= XFS_MOUNT_32BITINODES;
+	} else {
+		mp->m_flags &= ~XFS_MOUNT_32BITINODES;
+	}
+
+	/* If we can overflow then setup the ag headers accordingly */
+	if (mp->m_flags & XFS_MOUNT_32BITINODES) {
+		/* Calculate how much should be reserved for inodes to
+		 * meet the max inode percentage.
+		 */
+		if (mp->m_maxicount) {
+			__uint64_t	icount;
+
+			icount = sbp->sb_dblocks * sbp->sb_imax_pct;
+			do_div(icount, 100);
+			icount += sbp->sb_agblocks - 1;
+			do_div(icount, mp->m_ialloc_blks);
+			max_metadata = icount;
+		} else {
+			max_metadata = agcount;
+		}
+		for (index = 0; index < agcount; index++) {
+			ino = XFS_AGINO_TO_INO(mp, index, agino);
+			if (ino > max_inum) {
+				index++;
+				break;
+			}
+
+			/* This ag is prefered for inodes */
+			pag = &mp->m_perag[index];
+			pag->pagi_inodeok = 1;
+			if (index < max_metadata)
+				pag->pagf_metadata = 1;
+		}
+	} else {
+		/* Setup default behavior for smaller filesystems */
+		for (index = 0; index < agcount; index++) {
+			pag = &mp->m_perag[index];
+			pag->pagi_inodeok = 1;
+		}
+	}
+	return index;
+}
+
+/*
+ * xfs_xlatesb
+ *
+ *     data       - on disk version of sb
+ *     sb         - a superblock
+ *     dir        - conversion direction: <0 - convert sb to buf
+ *                                        >0 - convert buf to sb
+ *     fields     - which fields to copy (bitmask)
+ */
+void
+xfs_xlatesb(
+	void		*data,
+	xfs_sb_t	*sb,
+	int		dir,
+	__int64_t	fields)
+{
+	xfs_caddr_t	buf_ptr;
+	xfs_caddr_t	mem_ptr;
+	xfs_sb_field_t	f;
+	int		first;
+	int		size;
+
+	ASSERT(dir);
+	ASSERT(fields);
+
+	if (!fields)
+		return;
+
+	buf_ptr = (xfs_caddr_t)data;
+	mem_ptr = (xfs_caddr_t)sb;
+
+	while (fields) {
+		f = (xfs_sb_field_t)xfs_lowbit64((__uint64_t)fields);
+		first = xfs_sb_info[f].offset;
+		size = xfs_sb_info[f + 1].offset - first;
+
+		ASSERT(xfs_sb_info[f].type == 0 || xfs_sb_info[f].type == 1);
+
+		if (size == 1 || xfs_sb_info[f].type == 1) {
+			if (dir > 0) {
+				memcpy(mem_ptr + first, buf_ptr + first, size);
+			} else {
+				memcpy(buf_ptr + first, mem_ptr + first, size);
+			}
+		} else {
+			switch (size) {
+			case 2:
+				INT_XLATE(*(__uint16_t*)(buf_ptr+first),
+					  *(__uint16_t*)(mem_ptr+first),
+					  dir, ARCH_CONVERT);
+				break;
+			case 4:
+				INT_XLATE(*(__uint32_t*)(buf_ptr+first),
+					  *(__uint32_t*)(mem_ptr+first),
+					  dir, ARCH_CONVERT);
+				break;
+			case 8:
+				INT_XLATE(*(__uint64_t*)(buf_ptr+first),
+					  *(__uint64_t*)(mem_ptr+first), dir, ARCH_CONVERT);
+				break;
+			default:
+				ASSERT(0);
+			}
+		}
+
+		fields &= ~(1LL << f);
+	}
+}
+
+/*
+ * xfs_readsb
+ *
+ * Does the initial read of the superblock.
+ */
+int
+xfs_readsb(xfs_mount_t *mp)
+{
+	unsigned int	sector_size;
+	unsigned int	extra_flags;
+	xfs_buf_t	*bp;
+	xfs_sb_t	*sbp;
+	int		error;
+
+	ASSERT(mp->m_sb_bp == NULL);
+	ASSERT(mp->m_ddev_targp != NULL);
+
+	/*
+	 * Allocate a (locked) buffer to hold the superblock.
+	 * This will be kept around at all times to optimize
+	 * access to the superblock.
+	 */
+	sector_size = xfs_getsize_buftarg(mp->m_ddev_targp);
+	extra_flags = XFS_BUF_LOCK | XFS_BUF_MANAGE | XFS_BUF_MAPPED;
+
+	bp = xfs_buf_read_flags(mp->m_ddev_targp, XFS_SB_DADDR,
+				BTOBB(sector_size), extra_flags);
+	if (!bp || XFS_BUF_ISERROR(bp)) {
+		cmn_err(CE_WARN, "XFS: SB read failed");
+		error = bp ? XFS_BUF_GETERROR(bp) : ENOMEM;
+		goto fail;
+	}
+	ASSERT(XFS_BUF_ISBUSY(bp));
+	ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
+
+	/*
+	 * Initialize the mount structure from the superblock.
+	 * But first do some basic consistency checking.
+	 */
+	sbp = XFS_BUF_TO_SBP(bp);
+	xfs_xlatesb(XFS_BUF_PTR(bp), &(mp->m_sb), 1, XFS_SB_ALL_BITS);
+
+	error = xfs_mount_validate_sb(mp, &(mp->m_sb));
+	if (error) {
+		cmn_err(CE_WARN, "XFS: SB validate failed");
+		goto fail;
+	}
+
+	/*
+	 * We must be able to do sector-sized and sector-aligned IO.
+	 */
+	if (sector_size > mp->m_sb.sb_sectsize) {
+		cmn_err(CE_WARN,
+			"XFS: device supports only %u byte sectors (not %u)",
+			sector_size, mp->m_sb.sb_sectsize);
+		error = ENOSYS;
+		goto fail;
+	}
+
+	/*
+	 * If device sector size is smaller than the superblock size,
+	 * re-read the superblock so the buffer is correctly sized.
+	 */
+	if (sector_size < mp->m_sb.sb_sectsize) {
+		XFS_BUF_UNMANAGE(bp);
+		xfs_buf_relse(bp);
+		sector_size = mp->m_sb.sb_sectsize;
+		bp = xfs_buf_read_flags(mp->m_ddev_targp, XFS_SB_DADDR,
+					BTOBB(sector_size), extra_flags);
+		if (!bp || XFS_BUF_ISERROR(bp)) {
+			cmn_err(CE_WARN, "XFS: SB re-read failed");
+			error = bp ? XFS_BUF_GETERROR(bp) : ENOMEM;
+			goto fail;
+		}
+		ASSERT(XFS_BUF_ISBUSY(bp));
+		ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
+	}
+
+	mp->m_sb_bp = bp;
+	xfs_buf_relse(bp);
+	ASSERT(XFS_BUF_VALUSEMA(bp) > 0);
+	return 0;
+
+ fail:
+	if (bp) {
+		XFS_BUF_UNMANAGE(bp);
+		xfs_buf_relse(bp);
+	}
+	return error;
+}
+
+
+/*
+ * xfs_mount_common
+ *
+ * Mount initialization code establishing various mount
+ * fields from the superblock associated with the given
+ * mount structure
+ */
+void
+xfs_mount_common(xfs_mount_t *mp, xfs_sb_t *sbp)
+{
+	int	i;
+
+	mp->m_agfrotor = mp->m_agirotor = 0;
+	spinlock_init(&mp->m_agirotor_lock, "m_agirotor_lock");
+	mp->m_maxagi = mp->m_sb.sb_agcount;
+	mp->m_blkbit_log = sbp->sb_blocklog + XFS_NBBYLOG;
+	mp->m_blkbb_log = sbp->sb_blocklog - BBSHIFT;
+	mp->m_sectbb_log = sbp->sb_sectlog - BBSHIFT;
+	mp->m_agno_log = xfs_highbit32(sbp->sb_agcount - 1) + 1;
+	mp->m_agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
+	mp->m_litino = sbp->sb_inodesize -
+		((uint)sizeof(xfs_dinode_core_t) + (uint)sizeof(xfs_agino_t));
+	mp->m_blockmask = sbp->sb_blocksize - 1;
+	mp->m_blockwsize = sbp->sb_blocksize >> XFS_WORDLOG;
+	mp->m_blockwmask = mp->m_blockwsize - 1;
+	INIT_LIST_HEAD(&mp->m_del_inodes);
+
+	/*
+	 * Setup for attributes, in case they get created.
+	 * This value is for inodes getting attributes for the first time,
+	 * the per-inode value is for old attribute values.
+	 */
+	ASSERT(sbp->sb_inodesize >= 256 && sbp->sb_inodesize <= 2048);
+	switch (sbp->sb_inodesize) {
+	case 256:
+		mp->m_attroffset = XFS_LITINO(mp) - XFS_BMDR_SPACE_CALC(2);
+		break;
+	case 512:
+	case 1024:
+	case 2048:
+		mp->m_attroffset = XFS_BMDR_SPACE_CALC(12);
+		break;
+	default:
+		ASSERT(0);
+	}
+	ASSERT(mp->m_attroffset < XFS_LITINO(mp));
+
+	for (i = 0; i < 2; i++) {
+		mp->m_alloc_mxr[i] = XFS_BTREE_BLOCK_MAXRECS(sbp->sb_blocksize,
+			xfs_alloc, i == 0);
+		mp->m_alloc_mnr[i] = XFS_BTREE_BLOCK_MINRECS(sbp->sb_blocksize,
+			xfs_alloc, i == 0);
+	}
+	for (i = 0; i < 2; i++) {
+		mp->m_bmap_dmxr[i] = XFS_BTREE_BLOCK_MAXRECS(sbp->sb_blocksize,
+			xfs_bmbt, i == 0);
+		mp->m_bmap_dmnr[i] = XFS_BTREE_BLOCK_MINRECS(sbp->sb_blocksize,
+			xfs_bmbt, i == 0);
+	}
+	for (i = 0; i < 2; i++) {
+		mp->m_inobt_mxr[i] = XFS_BTREE_BLOCK_MAXRECS(sbp->sb_blocksize,
+			xfs_inobt, i == 0);
+		mp->m_inobt_mnr[i] = XFS_BTREE_BLOCK_MINRECS(sbp->sb_blocksize,
+			xfs_inobt, i == 0);
+	}
+
+	mp->m_bsize = XFS_FSB_TO_BB(mp, 1);
+	mp->m_ialloc_inos = (int)MAX((__uint16_t)XFS_INODES_PER_CHUNK,
+					sbp->sb_inopblock);
+	mp->m_ialloc_blks = mp->m_ialloc_inos >> sbp->sb_inopblog;
+}
+/*
+ * xfs_mountfs
+ *
+ * This function does the following on an initial mount of a file system:
+ *	- reads the superblock from disk and init the mount struct
+ *	- if we're a 32-bit kernel, do a size check on the superblock
+ *		so we don't mount terabyte filesystems
+ *	- init mount struct realtime fields
+ *	- allocate inode hash table for fs
+ *	- init directory manager
+ *	- perform recovery and init the log manager
+ */
+int
+xfs_mountfs(
+	vfs_t		*vfsp,
+	xfs_mount_t	*mp,
+	int		mfsi_flags)
+{
+	xfs_buf_t	*bp;
+	xfs_sb_t	*sbp = &(mp->m_sb);
+	xfs_inode_t	*rip;
+	vnode_t		*rvp = NULL;
+	int		readio_log, writeio_log;
+	xfs_daddr_t	d;
+	__uint64_t	ret64;
+	__int64_t	update_flags;
+	uint		quotamount, quotaflags;
+	int		agno;
+	int		uuid_mounted = 0;
+	int		error = 0;
+
+	if (mp->m_sb_bp == NULL) {
+		if ((error = xfs_readsb(mp))) {
+			return (error);
+		}
+	}
+	xfs_mount_common(mp, sbp);
+
+	/*
+	 * Check if sb_agblocks is aligned at stripe boundary
+	 * If sb_agblocks is NOT aligned turn off m_dalign since
+	 * allocator alignment is within an ag, therefore ag has
+	 * to be aligned at stripe boundary.
+	 */
+	update_flags = 0LL;
+	if (mp->m_dalign && !(mfsi_flags & XFS_MFSI_SECOND)) {
+		/*
+		 * If stripe unit and stripe width are not multiples
+		 * of the fs blocksize turn off alignment.
+		 */
+		if ((BBTOB(mp->m_dalign) & mp->m_blockmask) ||
+		    (BBTOB(mp->m_swidth) & mp->m_blockmask)) {
+			if (mp->m_flags & XFS_MOUNT_RETERR) {
+				cmn_err(CE_WARN,
+					"XFS: alignment check 1 failed");
+				error = XFS_ERROR(EINVAL);
+				goto error1;
+			}
+			mp->m_dalign = mp->m_swidth = 0;
+		} else {
+			/*
+			 * Convert the stripe unit and width to FSBs.
+			 */
+			mp->m_dalign = XFS_BB_TO_FSBT(mp, mp->m_dalign);
+			if (mp->m_dalign && (sbp->sb_agblocks % mp->m_dalign)) {
+				if (mp->m_flags & XFS_MOUNT_RETERR) {
+					error = XFS_ERROR(EINVAL);
+					goto error1;
+				}
+				xfs_fs_cmn_err(CE_WARN, mp,
+"stripe alignment turned off: sunit(%d)/swidth(%d) incompatible with agsize(%d)",
+					mp->m_dalign, mp->m_swidth,
+					sbp->sb_agblocks);
+
+				mp->m_dalign = 0;
+				mp->m_swidth = 0;
+			} else if (mp->m_dalign) {
+				mp->m_swidth = XFS_BB_TO_FSBT(mp, mp->m_swidth);
+			} else {
+				if (mp->m_flags & XFS_MOUNT_RETERR) {
+					xfs_fs_cmn_err(CE_WARN, mp,
+"stripe alignment turned off: sunit(%d) less than bsize(%d)",
+                                        	mp->m_dalign,
+						mp->m_blockmask +1);
+					error = XFS_ERROR(EINVAL);
+					goto error1;
+				}
+				mp->m_swidth = 0;
+			}
+		}
+
+		/*
+		 * Update superblock with new values
+		 * and log changes
+		 */
+		if (XFS_SB_VERSION_HASDALIGN(sbp)) {
+			if (sbp->sb_unit != mp->m_dalign) {
+				sbp->sb_unit = mp->m_dalign;
+				update_flags |= XFS_SB_UNIT;
+			}
+			if (sbp->sb_width != mp->m_swidth) {
+				sbp->sb_width = mp->m_swidth;
+				update_flags |= XFS_SB_WIDTH;
+			}
+		}
+	} else if ((mp->m_flags & XFS_MOUNT_NOALIGN) != XFS_MOUNT_NOALIGN &&
+		    XFS_SB_VERSION_HASDALIGN(&mp->m_sb)) {
+			mp->m_dalign = sbp->sb_unit;
+			mp->m_swidth = sbp->sb_width;
+	}
+
+	xfs_alloc_compute_maxlevels(mp);
+	xfs_bmap_compute_maxlevels(mp, XFS_DATA_FORK);
+	xfs_bmap_compute_maxlevels(mp, XFS_ATTR_FORK);
+	xfs_ialloc_compute_maxlevels(mp);
+
+	if (sbp->sb_imax_pct) {
+		__uint64_t	icount;
+
+		/* Make sure the maximum inode count is a multiple of the
+		 * units we allocate inodes in.
+		 */
+
+		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
+		do_div(icount, 100);
+		do_div(icount, mp->m_ialloc_blks);
+		mp->m_maxicount = (icount * mp->m_ialloc_blks)  <<
+				   sbp->sb_inopblog;
+	} else
+		mp->m_maxicount = 0;
+
+	mp->m_maxioffset = xfs_max_file_offset(sbp->sb_blocklog);
+
+	/*
+	 * XFS uses the uuid from the superblock as the unique
+	 * identifier for fsid.  We can not use the uuid from the volume
+	 * since a single partition filesystem is identical to a single
+	 * partition volume/filesystem.
+	 */
+	if ((mfsi_flags & XFS_MFSI_SECOND) == 0 &&
+	    (mp->m_flags & XFS_MOUNT_NOUUID) == 0) {
+		if (xfs_uuid_mount(mp)) {
+			error = XFS_ERROR(EINVAL);
+			goto error1;
+		}
+		uuid_mounted=1;
+		ret64 = uuid_hash64(&sbp->sb_uuid);
+		memcpy(&vfsp->vfs_fsid, &ret64, sizeof(ret64));
+	}
+
+	/*
+	 * Set the default minimum read and write sizes unless
+	 * already specified in a mount option.
+	 * We use smaller I/O sizes when the file system
+	 * is being used for NFS service (wsync mount option).
+	 */
+	if (!(mp->m_flags & XFS_MOUNT_DFLT_IOSIZE)) {
+		if (mp->m_flags & XFS_MOUNT_WSYNC) {
+			readio_log = XFS_WSYNC_READIO_LOG;
+			writeio_log = XFS_WSYNC_WRITEIO_LOG;
+		} else {
+			readio_log = XFS_READIO_LOG_LARGE;
+			writeio_log = XFS_WRITEIO_LOG_LARGE;
+		}
+	} else {
+		readio_log = mp->m_readio_log;
+		writeio_log = mp->m_writeio_log;
+	}
+
+	/*
+	 * Set the number of readahead buffers to use based on
+	 * physical memory size.
+	 */
+	if (xfs_physmem <= 4096)		/* <= 16MB */
+		mp->m_nreadaheads = XFS_RW_NREADAHEAD_16MB;
+	else if (xfs_physmem <= 8192)	/* <= 32MB */
+		mp->m_nreadaheads = XFS_RW_NREADAHEAD_32MB;
+	else
+		mp->m_nreadaheads = XFS_RW_NREADAHEAD_K32;
+	if (sbp->sb_blocklog > readio_log) {
+		mp->m_readio_log = sbp->sb_blocklog;
+	} else {
+		mp->m_readio_log = readio_log;
+	}
+	mp->m_readio_blocks = 1 << (mp->m_readio_log - sbp->sb_blocklog);
+	if (sbp->sb_blocklog > writeio_log) {
+		mp->m_writeio_log = sbp->sb_blocklog;
+	} else {
+		mp->m_writeio_log = writeio_log;
+	}
+	mp->m_writeio_blocks = 1 << (mp->m_writeio_log - sbp->sb_blocklog);
+
+	/*
+	 * Set the inode cluster size based on the physical memory
+	 * size.  This may still be overridden by the file system
+	 * block size if it is larger than the chosen cluster size.
+	 */
+	if (xfs_physmem <= btoc(32 * 1024 * 1024)) { /* <= 32 MB */
+		mp->m_inode_cluster_size = XFS_INODE_SMALL_CLUSTER_SIZE;
+	} else {
+		mp->m_inode_cluster_size = XFS_INODE_BIG_CLUSTER_SIZE;
+	}
+	/*
+	 * Set whether we're using inode alignment.
+	 */
+	if (XFS_SB_VERSION_HASALIGN(&mp->m_sb) &&
+	    mp->m_sb.sb_inoalignmt >=
+	    XFS_B_TO_FSBT(mp, mp->m_inode_cluster_size))
+		mp->m_inoalign_mask = mp->m_sb.sb_inoalignmt - 1;
+	else
+		mp->m_inoalign_mask = 0;
+	/*
+	 * If we are using stripe alignment, check whether
+	 * the stripe unit is a multiple of the inode alignment
+	 */
+	if (mp->m_dalign && mp->m_inoalign_mask &&
+	    !(mp->m_dalign & mp->m_inoalign_mask))
+		mp->m_sinoalign = mp->m_dalign;
+	else
+		mp->m_sinoalign = 0;
+	/*
+	 * Check that the data (and log if separate) are an ok size.
+	 */
+	d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);
+	if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_dblocks) {
+		cmn_err(CE_WARN, "XFS: size check 1 failed");
+		error = XFS_ERROR(E2BIG);
+		goto error1;
+	}
+	error = xfs_read_buf(mp, mp->m_ddev_targp,
+			     d - XFS_FSS_TO_BB(mp, 1),
+			     XFS_FSS_TO_BB(mp, 1), 0, &bp);
+	if (!error) {
+		xfs_buf_relse(bp);
+	} else {
+		cmn_err(CE_WARN, "XFS: size check 2 failed");
+		if (error == ENOSPC) {
+			error = XFS_ERROR(E2BIG);
+		}
+		goto error1;
+	}
+
+	if (((mfsi_flags & XFS_MFSI_CLIENT) == 0) &&
+	    mp->m_logdev_targp != mp->m_ddev_targp) {
+		d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_logblocks);
+		if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_logblocks) {
+			cmn_err(CE_WARN, "XFS: size check 3 failed");
+			error = XFS_ERROR(E2BIG);
+			goto error1;
+		}
+		error = xfs_read_buf(mp, mp->m_logdev_targp,
+				     d - XFS_FSB_TO_BB(mp, 1),
+				     XFS_FSB_TO_BB(mp, 1), 0, &bp);
+		if (!error) {
+			xfs_buf_relse(bp);
+		} else {
+			cmn_err(CE_WARN, "XFS: size check 3 failed");
+			if (error == ENOSPC) {
+				error = XFS_ERROR(E2BIG);
+			}
+			goto error1;
+		}
+	}
+
+	/*
+	 * Initialize realtime fields in the mount structure
+	 */
+	if ((error = xfs_rtmount_init(mp))) {
+		cmn_err(CE_WARN, "XFS: RT mount failed");
+		goto error1;
+	}
+
+	/*
+	 * For client case we are done now
+	 */
+	if (mfsi_flags & XFS_MFSI_CLIENT) {
+		return(0);
+	}
+
+	/*
+	 *  Copies the low order bits of the timestamp and the randomly
+	 *  set "sequence" number out of a UUID.
+	 */
+	uuid_getnodeuniq(&sbp->sb_uuid, mp->m_fixedfsid);
+
+	/*
+	 *  The vfs structure needs to have a file system independent
+	 *  way of checking for the invariant file system ID.  Since it
+	 *  can't look at mount structures it has a pointer to the data
+	 *  in the mount structure.
+	 *
+	 *  File systems that don't support user level file handles (i.e.
+	 *  all of them except for XFS) will leave vfs_altfsid as NULL.
+	 */
+	vfsp->vfs_altfsid = (xfs_fsid_t *)mp->m_fixedfsid;
+	mp->m_dmevmask = 0;	/* not persistent; set after each mount */
+
+	/*
+	 * Select the right directory manager.
+	 */
+	mp->m_dirops =
+		XFS_SB_VERSION_HASDIRV2(&mp->m_sb) ?
+			xfsv2_dirops :
+			xfsv1_dirops;
+
+	/*
+	 * Initialize directory manager's entries.
+	 */
+	XFS_DIR_MOUNT(mp);
+
+	/*
+	 * Initialize the attribute manager's entries.
+	 */
+	mp->m_attr_magicpct = (mp->m_sb.sb_blocksize * 37) / 100;
+
+	/*
+	 * Initialize the precomputed transaction reservations values.
+	 */
+	xfs_trans_init(mp);
+
+	/*
+	 * Allocate and initialize the inode hash table for this
+	 * file system.
+	 */
+	xfs_ihash_init(mp);
+	xfs_chash_init(mp);
+
+	/*
+	 * Allocate and initialize the per-ag data.
+	 */
+	init_rwsem(&mp->m_peraglock);
+	mp->m_perag =
+		kmem_zalloc(sbp->sb_agcount * sizeof(xfs_perag_t), KM_SLEEP);
+
+	mp->m_maxagi = xfs_initialize_perag(mp, sbp->sb_agcount);
+
+	/*
+	 * log's mount-time initialization. Perform 1st part recovery if needed
+	 */
+	if (likely(sbp->sb_logblocks > 0)) {	/* check for volume case */
+		error = xfs_log_mount(mp, mp->m_logdev_targp,
+				      XFS_FSB_TO_DADDR(mp, sbp->sb_logstart),
+				      XFS_FSB_TO_BB(mp, sbp->sb_logblocks));
+		if (error) {
+			cmn_err(CE_WARN, "XFS: log mount failed");
+			goto error2;
+		}
+	} else {	/* No log has been defined */
+		cmn_err(CE_WARN, "XFS: no log defined");
+		XFS_ERROR_REPORT("xfs_mountfs_int(1)", XFS_ERRLEVEL_LOW, mp);
+		error = XFS_ERROR(EFSCORRUPTED);
+		goto error2;
+	}
+
+	/*
+	 * Get and sanity-check the root inode.
+	 * Save the pointer to it in the mount structure.
+	 */
+	error = xfs_iget(mp, NULL, sbp->sb_rootino, 0, XFS_ILOCK_EXCL, &rip, 0);
+	if (error) {
+		cmn_err(CE_WARN, "XFS: failed to read root inode");
+		goto error3;
+	}
+
+	ASSERT(rip != NULL);
+	rvp = XFS_ITOV(rip);
+
+	if (unlikely((rip->i_d.di_mode & S_IFMT) != S_IFDIR)) {
+		cmn_err(CE_WARN, "XFS: corrupted root inode");
+		prdev("Root inode %llu is not a directory",
+		      mp->m_ddev_targp, (unsigned long long)rip->i_ino);
+		xfs_iunlock(rip, XFS_ILOCK_EXCL);
+		XFS_ERROR_REPORT("xfs_mountfs_int(2)", XFS_ERRLEVEL_LOW,
+				 mp);
+		error = XFS_ERROR(EFSCORRUPTED);
+		goto error4;
+	}
+	mp->m_rootip = rip;	/* save it */
+
+	xfs_iunlock(rip, XFS_ILOCK_EXCL);
+
+	/*
+	 * Initialize realtime inode pointers in the mount structure
+	 */
+	if ((error = xfs_rtmount_inodes(mp))) {
+		/*
+		 * Free up the root inode.
+		 */
+		cmn_err(CE_WARN, "XFS: failed to read RT inodes");
+		goto error4;
+	}
+
+	/*
+	 * If fs is not mounted readonly, then update the superblock
+	 * unit and width changes.
+	 */
+	if (update_flags && !(vfsp->vfs_flag & VFS_RDONLY))
+		xfs_mount_log_sbunit(mp, update_flags);
+
+	/*
+	 * Initialise the XFS quota management subsystem for this mount
+	 */
+	if ((error = XFS_QM_INIT(mp, &quotamount, &quotaflags)))
+		goto error4;
+
+	/*
+	 * Finish recovering the file system.  This part needed to be
+	 * delayed until after the root and real-time bitmap inodes
+	 * were consistently read in.
+	 */
+	error = xfs_log_mount_finish(mp, mfsi_flags);
+	if (error) {
+		cmn_err(CE_WARN, "XFS: log mount finish failed");
+		goto error4;
+	}
+
+	/*
+	 * Complete the quota initialisation, post-log-replay component.
+	 */
+	if ((error = XFS_QM_MOUNT(mp, quotamount, quotaflags, mfsi_flags)))
+		goto error4;
+
+	return 0;
+
+ error4:
+	/*
+	 * Free up the root inode.
+	 */
+	VN_RELE(rvp);
+ error3:
+	xfs_log_unmount_dealloc(mp);
+ error2:
+	xfs_ihash_free(mp);
+	xfs_chash_free(mp);
+	for (agno = 0; agno < sbp->sb_agcount; agno++)
+		if (mp->m_perag[agno].pagb_list)
+			kmem_free(mp->m_perag[agno].pagb_list,
+			  sizeof(xfs_perag_busy_t) * XFS_PAGB_NUM_SLOTS);
+	kmem_free(mp->m_perag, sbp->sb_agcount * sizeof(xfs_perag_t));
+	mp->m_perag = NULL;
+	/* FALLTHROUGH */
+ error1:
+	if (uuid_mounted)
+		xfs_uuid_unmount(mp);
+	xfs_freesb(mp);
+	return error;
+}
+
+/*
+ * xfs_unmountfs
+ *
+ * This flushes out the inodes,dquots and the superblock, unmounts the
+ * log and makes sure that incore structures are freed.
+ */
+int
+xfs_unmountfs(xfs_mount_t *mp, struct cred *cr)
+{
+	struct vfs	*vfsp = XFS_MTOVFS(mp);
+#if defined(DEBUG) || defined(INDUCE_IO_ERROR)
+	int64_t		fsid;
+#endif
+
+	xfs_iflush_all(mp, XFS_FLUSH_ALL);
+
+	XFS_QM_DQPURGEALL(mp,
+		XFS_QMOPT_UQUOTA | XFS_QMOPT_GQUOTA | XFS_QMOPT_UMOUNTING);
+
+	/*
+	 * Flush out the log synchronously so that we know for sure
+	 * that nothing is pinned.  This is important because bflush()
+	 * will skip pinned buffers.
+	 */
+	xfs_log_force(mp, (xfs_lsn_t)0, XFS_LOG_FORCE | XFS_LOG_SYNC);
+
+	xfs_binval(mp->m_ddev_targp);
+	if (mp->m_rtdev_targp) {
+		xfs_binval(mp->m_rtdev_targp);
+	}
+
+	xfs_unmountfs_writesb(mp);
+
+	xfs_unmountfs_wait(mp); 		/* wait for async bufs */
+
+	xfs_log_unmount(mp);			/* Done! No more fs ops. */
+
+	xfs_freesb(mp);
+
+	/*
+	 * All inodes from this mount point should be freed.
+	 */
+	ASSERT(mp->m_inodes == NULL);
+
+	/*
+	 * We may have bufs that are in the process of getting written still.
+	 * We must wait for the I/O completion of those. The sync flag here
+	 * does a two pass iteration thru the bufcache.
+	 */
+	if (XFS_FORCED_SHUTDOWN(mp)) {
+		xfs_incore_relse(mp->m_ddev_targp, 0, 1); /* synchronous */
+	}
+
+	xfs_unmountfs_close(mp, cr);
+	if ((mp->m_flags & XFS_MOUNT_NOUUID) == 0)
+		xfs_uuid_unmount(mp);
+
+#if defined(DEBUG) || defined(INDUCE_IO_ERROR)
+	/*
+	 * clear all error tags on this filesystem
+	 */
+	memcpy(&fsid, &vfsp->vfs_fsid, sizeof(int64_t));
+	xfs_errortag_clearall_umount(fsid, mp->m_fsname, 0);
+#endif
+	XFS_IODONE(vfsp);
+	xfs_mount_free(mp, 1);
+	return 0;
+}
+
+void
+xfs_unmountfs_close(xfs_mount_t *mp, struct cred *cr)
+{
+	if (mp->m_logdev_targp != mp->m_ddev_targp)
+		xfs_free_buftarg(mp->m_logdev_targp, 1);
+	if (mp->m_rtdev_targp)
+		xfs_free_buftarg(mp->m_rtdev_targp, 1);
+	xfs_free_buftarg(mp->m_ddev_targp, 0);
+}
+
+void
+xfs_unmountfs_wait(xfs_mount_t *mp)
+{
+	if (mp->m_logdev_targp != mp->m_ddev_targp)
+		xfs_wait_buftarg(mp->m_logdev_targp);
+	if (mp->m_rtdev_targp)
+		xfs_wait_buftarg(mp->m_rtdev_targp);
+	xfs_wait_buftarg(mp->m_ddev_targp);
+}
+
+int
+xfs_unmountfs_writesb(xfs_mount_t *mp)
+{
+	xfs_buf_t	*sbp;
+	xfs_sb_t	*sb;
+	int		error = 0;
+
+	/*
+	 * skip superblock write if fs is read-only, or
+	 * if we are doing a forced umount.
+	 */
+	sbp = xfs_getsb(mp, 0);
+	if (!(XFS_MTOVFS(mp)->vfs_flag & VFS_RDONLY ||
+		XFS_FORCED_SHUTDOWN(mp))) {
+		/*
+		 * mark shared-readonly if desired
+		 */
+		sb = XFS_BUF_TO_SBP(sbp);
+		if (mp->m_mk_sharedro) {
+			if (!(sb->sb_flags & XFS_SBF_READONLY))
+				sb->sb_flags |= XFS_SBF_READONLY;
+			if (!XFS_SB_VERSION_HASSHARED(sb))
+				XFS_SB_VERSION_ADDSHARED(sb);
+			xfs_fs_cmn_err(CE_NOTE, mp,
+				"Unmounting, marking shared read-only");
+		}
+		XFS_BUF_UNDONE(sbp);
+		XFS_BUF_UNREAD(sbp);
+		XFS_BUF_UNDELAYWRITE(sbp);
+		XFS_BUF_WRITE(sbp);
+		XFS_BUF_UNASYNC(sbp);
+		ASSERT(XFS_BUF_TARGET(sbp) == mp->m_ddev_targp);
+		xfsbdstrat(mp, sbp);
+		/* Nevermind errors we might get here. */
+		error = xfs_iowait(sbp);
+		if (error)
+			xfs_ioerror_alert("xfs_unmountfs_writesb",
+					  mp, sbp, XFS_BUF_ADDR(sbp));
+		if (error && mp->m_mk_sharedro)
+			xfs_fs_cmn_err(CE_ALERT, mp, "Superblock write error detected while unmounting.  Filesystem may not be marked shared readonly");
+	}
+	xfs_buf_relse(sbp);
+	return (error);
+}
+
+/*
+ * xfs_mod_sb() can be used to copy arbitrary changes to the
+ * in-core superblock into the superblock buffer to be logged.
+ * It does not provide the higher level of locking that is
+ * needed to protect the in-core superblock from concurrent
+ * access.
+ */
+void
+xfs_mod_sb(xfs_trans_t *tp, __int64_t fields)
+{
+	xfs_buf_t	*bp;
+	int		first;
+	int		last;
+	xfs_mount_t	*mp;
+	xfs_sb_t	*sbp;
+	xfs_sb_field_t	f;
+
+	ASSERT(fields);
+	if (!fields)
+		return;
+	mp = tp->t_mountp;
+	bp = xfs_trans_getsb(tp, mp, 0);
+	sbp = XFS_BUF_TO_SBP(bp);
+	first = sizeof(xfs_sb_t);
+	last = 0;
+
+	/* translate/copy */
+
+	xfs_xlatesb(XFS_BUF_PTR(bp), &(mp->m_sb), -1, fields);
+
+	/* find modified range */
+
+	f = (xfs_sb_field_t)xfs_lowbit64((__uint64_t)fields);
+	ASSERT((1LL << f) & XFS_SB_MOD_BITS);
+	first = xfs_sb_info[f].offset;
+
+	f = (xfs_sb_field_t)xfs_highbit64((__uint64_t)fields);
+	ASSERT((1LL << f) & XFS_SB_MOD_BITS);
+	last = xfs_sb_info[f + 1].offset - 1;
+
+	xfs_trans_log_buf(tp, bp, first, last);
+}
+
+/*
+ * xfs_mod_incore_sb_unlocked() is a utility routine common used to apply
+ * a delta to a specified field in the in-core superblock.  Simply
+ * switch on the field indicated and apply the delta to that field.
+ * Fields are not allowed to dip below zero, so if the delta would
+ * do this do not apply it and return EINVAL.
+ *
+ * The SB_LOCK must be held when this routine is called.
+ */
+STATIC int
+xfs_mod_incore_sb_unlocked(xfs_mount_t *mp, xfs_sb_field_t field,
+			int delta, int rsvd)
+{
+	int		scounter;	/* short counter for 32 bit fields */
+	long long	lcounter;	/* long counter for 64 bit fields */
+	long long	res_used, rem;
+
+	/*
+	 * With the in-core superblock spin lock held, switch
+	 * on the indicated field.  Apply the delta to the
+	 * proper field.  If the fields value would dip below
+	 * 0, then do not apply the delta and return EINVAL.
+	 */
+	switch (field) {
+	case XFS_SBS_ICOUNT:
+		lcounter = (long long)mp->m_sb.sb_icount;
+		lcounter += delta;
+		if (lcounter < 0) {
+			ASSERT(0);
+			return (XFS_ERROR(EINVAL));
+		}
+		mp->m_sb.sb_icount = lcounter;
+		return (0);
+	case XFS_SBS_IFREE:
+		lcounter = (long long)mp->m_sb.sb_ifree;
+		lcounter += delta;
+		if (lcounter < 0) {
+			ASSERT(0);
+			return (XFS_ERROR(EINVAL));
+		}
+		mp->m_sb.sb_ifree = lcounter;
+		return (0);
+	case XFS_SBS_FDBLOCKS:
+
+		lcounter = (long long)mp->m_sb.sb_fdblocks;
+		res_used = (long long)(mp->m_resblks - mp->m_resblks_avail);
+
+		if (delta > 0) {		/* Putting blocks back */
+			if (res_used > delta) {
+				mp->m_resblks_avail += delta;
+			} else {
+				rem = delta - res_used;
+				mp->m_resblks_avail = mp->m_resblks;
+				lcounter += rem;
+			}
+		} else {				/* Taking blocks away */
+
+			lcounter += delta;
+
+		/*
+		 * If were out of blocks, use any available reserved blocks if
+		 * were allowed to.
+		 */
+
+			if (lcounter < 0) {
+				if (rsvd) {
+					lcounter = (long long)mp->m_resblks_avail + delta;
+					if (lcounter < 0) {
+						return (XFS_ERROR(ENOSPC));
+					}
+					mp->m_resblks_avail = lcounter;
+					return (0);
+				} else {	/* not reserved */
+					return (XFS_ERROR(ENOSPC));
+				}
+			}
+		}
+
+		mp->m_sb.sb_fdblocks = lcounter;
+		return (0);
+	case XFS_SBS_FREXTENTS:
+		lcounter = (long long)mp->m_sb.sb_frextents;
+		lcounter += delta;
+		if (lcounter < 0) {
+			return (XFS_ERROR(ENOSPC));
+		}
+		mp->m_sb.sb_frextents = lcounter;
+		return (0);
+	case XFS_SBS_DBLOCKS:
+		lcounter = (long long)mp->m_sb.sb_dblocks;
+		lcounter += delta;
+		if (lcounter < 0) {
+			ASSERT(0);
+			return (XFS_ERROR(EINVAL));
+		}
+		mp->m_sb.sb_dblocks = lcounter;
+		return (0);
+	case XFS_SBS_AGCOUNT:
+		scounter = mp->m_sb.sb_agcount;
+		scounter += delta;
+		if (scounter < 0) {
+			ASSERT(0);
+			return (XFS_ERROR(EINVAL));
+		}
+		mp->m_sb.sb_agcount = scounter;
+		return (0);
+	case XFS_SBS_IMAX_PCT:
+		scounter = mp->m_sb.sb_imax_pct;
+		scounter += delta;
+		if (scounter < 0) {
+			ASSERT(0);
+			return (XFS_ERROR(EINVAL));
+		}
+		mp->m_sb.sb_imax_pct = scounter;
+		return (0);
+	case XFS_SBS_REXTSIZE:
+		scounter = mp->m_sb.sb_rextsize;
+		scounter += delta;
+		if (scounter < 0) {
+			ASSERT(0);
+			return (XFS_ERROR(EINVAL));
+		}
+		mp->m_sb.sb_rextsize = scounter;
+		return (0);
+	case XFS_SBS_RBMBLOCKS:
+		scounter = mp->m_sb.sb_rbmblocks;
+		scounter += delta;
+		if (scounter < 0) {
+			ASSERT(0);
+			return (XFS_ERROR(EINVAL));
+		}
+		mp->m_sb.sb_rbmblocks = scounter;
+		return (0);
+	case XFS_SBS_RBLOCKS:
+		lcounter = (long long)mp->m_sb.sb_rblocks;
+		lcounter += delta;
+		if (lcounter < 0) {
+			ASSERT(0);
+			return (XFS_ERROR(EINVAL));
+		}
+		mp->m_sb.sb_rblocks = lcounter;
+		return (0);
+	case XFS_SBS_REXTENTS:
+		lcounter = (long long)mp->m_sb.sb_rextents;
+		lcounter += delta;
+		if (lcounter < 0) {
+			ASSERT(0);
+			return (XFS_ERROR(EINVAL));
+		}
+		mp->m_sb.sb_rextents = lcounter;
+		return (0);
+	case XFS_SBS_REXTSLOG:
+		scounter = mp->m_sb.sb_rextslog;
+		scounter += delta;
+		if (scounter < 0) {
+			ASSERT(0);
+			return (XFS_ERROR(EINVAL));
+		}
+		mp->m_sb.sb_rextslog = scounter;
+		return (0);
+	default:
+		ASSERT(0);
+		return (XFS_ERROR(EINVAL));
+	}
+}
+
+/*
+ * xfs_mod_incore_sb() is used to change a field in the in-core
+ * superblock structure by the specified delta.  This modification
+ * is protected by the SB_LOCK.  Just use the xfs_mod_incore_sb_unlocked()
+ * routine to do the work.
+ */
+int
+xfs_mod_incore_sb(xfs_mount_t *mp, xfs_sb_field_t field, int delta, int rsvd)
+{
+	unsigned long	s;
+	int	status;
+
+	s = XFS_SB_LOCK(mp);
+	status = xfs_mod_incore_sb_unlocked(mp, field, delta, rsvd);
+	XFS_SB_UNLOCK(mp, s);
+	return (status);
+}
+
+/*
+ * xfs_mod_incore_sb_batch() is used to change more than one field
+ * in the in-core superblock structure at a time.  This modification
+ * is protected by a lock internal to this module.  The fields and
+ * changes to those fields are specified in the array of xfs_mod_sb
+ * structures passed in.
+ *
+ * Either all of the specified deltas will be applied or none of
+ * them will.  If any modified field dips below 0, then all modifications
+ * will be backed out and EINVAL will be returned.
+ */
+int
+xfs_mod_incore_sb_batch(xfs_mount_t *mp, xfs_mod_sb_t *msb, uint nmsb, int rsvd)
+{
+	unsigned long	s;
+	int		status=0;
+	xfs_mod_sb_t	*msbp;
+
+	/*
+	 * Loop through the array of mod structures and apply each
+	 * individually.  If any fail, then back out all those
+	 * which have already been applied.  Do all of this within
+	 * the scope of the SB_LOCK so that all of the changes will
+	 * be atomic.
+	 */
+	s = XFS_SB_LOCK(mp);
+	msbp = &msb[0];
+	for (msbp = &msbp[0]; msbp < (msb + nmsb); msbp++) {
+		/*
+		 * Apply the delta at index n.  If it fails, break
+		 * from the loop so we'll fall into the undo loop
+		 * below.
+		 */
+		status = xfs_mod_incore_sb_unlocked(mp, msbp->msb_field,
+						    msbp->msb_delta, rsvd);
+		if (status != 0) {
+			break;
+		}
+	}
+
+	/*
+	 * If we didn't complete the loop above, then back out
+	 * any changes made to the superblock.  If you add code
+	 * between the loop above and here, make sure that you
+	 * preserve the value of status. Loop back until
+	 * we step below the beginning of the array.  Make sure
+	 * we don't touch anything back there.
+	 */
+	if (status != 0) {
+		msbp--;
+		while (msbp >= msb) {
+			status = xfs_mod_incore_sb_unlocked(mp,
+				    msbp->msb_field, -(msbp->msb_delta), rsvd);
+			ASSERT(status == 0);
+			msbp--;
+		}
+	}
+	XFS_SB_UNLOCK(mp, s);
+	return (status);
+}
+
+/*
+ * xfs_getsb() is called to obtain the buffer for the superblock.
+ * The buffer is returned locked and read in from disk.
+ * The buffer should be released with a call to xfs_brelse().
+ *
+ * If the flags parameter is BUF_TRYLOCK, then we'll only return
+ * the superblock buffer if it can be locked without sleeping.
+ * If it can't then we'll return NULL.
+ */
+xfs_buf_t *
+xfs_getsb(
+	xfs_mount_t	*mp,
+	int		flags)
+{
+	xfs_buf_t	*bp;
+
+	ASSERT(mp->m_sb_bp != NULL);
+	bp = mp->m_sb_bp;
+	if (flags & XFS_BUF_TRYLOCK) {
+		if (!XFS_BUF_CPSEMA(bp)) {
+			return NULL;
+		}
+	} else {
+		XFS_BUF_PSEMA(bp, PRIBIO);
+	}
+	XFS_BUF_HOLD(bp);
+	ASSERT(XFS_BUF_ISDONE(bp));
+	return (bp);
+}
+
+/*
+ * Used to free the superblock along various error paths.
+ */
+void
+xfs_freesb(
+	xfs_mount_t	*mp)
+{
+	xfs_buf_t	*bp;
+
+	/*
+	 * Use xfs_getsb() so that the buffer will be locked
+	 * when we call xfs_buf_relse().
+	 */
+	bp = xfs_getsb(mp, 0);
+	XFS_BUF_UNMANAGE(bp);
+	xfs_buf_relse(bp);
+	mp->m_sb_bp = NULL;
+}
+
+/*
+ * See if the UUID is unique among mounted XFS filesystems.
+ * Mount fails if UUID is nil or a FS with the same UUID is already mounted.
+ */
+STATIC int
+xfs_uuid_mount(
+	xfs_mount_t	*mp)
+{
+	if (uuid_is_nil(&mp->m_sb.sb_uuid)) {
+		cmn_err(CE_WARN,
+			"XFS: Filesystem %s has nil UUID - can't mount",
+			mp->m_fsname);
+		return -1;
+	}
+	if (!uuid_table_insert(&mp->m_sb.sb_uuid)) {
+		cmn_err(CE_WARN,
+			"XFS: Filesystem %s has duplicate UUID - can't mount",
+			mp->m_fsname);
+		return -1;
+	}
+	return 0;
+}
+
+/*
+ * Remove filesystem from the UUID table.
+ */
+STATIC void
+xfs_uuid_unmount(
+	xfs_mount_t	*mp)
+{
+	uuid_table_remove(&mp->m_sb.sb_uuid);
+}
+
+/*
+ * Used to log changes to the superblock unit and width fields which could
+ * be altered by the mount options. Only the first superblock is updated.
+ */
+STATIC void
+xfs_mount_log_sbunit(
+	xfs_mount_t	*mp,
+	__int64_t	fields)
+{
+	xfs_trans_t	*tp;
+
+	ASSERT(fields & (XFS_SB_UNIT|XFS_SB_WIDTH|XFS_SB_UUID));
+
+	tp = xfs_trans_alloc(mp, XFS_TRANS_SB_UNIT);
+	if (xfs_trans_reserve(tp, 0, mp->m_sb.sb_sectsize + 128, 0, 0,
+				XFS_DEFAULT_LOG_COUNT)) {
+		xfs_trans_cancel(tp, 0);
+		return;
+	}
+	xfs_mod_sb(tp, fields);
+	xfs_trans_commit(tp, 0, NULL);
+}