/*

   * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
   * All Rights Reserved.

   *

   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License as

   * published by the Free Software Foundation.
   *

   * This program is distributed in the hope that it would be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.

   *

   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write the Free Software Foundation,
   * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

   */

  #include "xfs.h"

  #include "xfs_fs.h"

  #include "xfs_types.h"

  #include "xfs_bit.h"

  #include "xfs_log.h"

  #include "xfs_inum.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_ialloc.h"
  #include "xfs_itable.h"
  #include "xfs_error.h"

  #include "xfs_btree.h"

  #include "xfs_trace.h"

  STATIC int

  xfs_internal_inum(
  	xfs_mount_t	*mp,
  	xfs_ino_t	ino)
  {
  	return (ino == mp->m_sb.sb_rbmino || ino == mp->m_sb.sb_rsumino ||

  		(xfs_sb_version_hasquota(&mp->m_sb) &&

  		 (ino == mp->m_sb.sb_uquotino || ino == mp->m_sb.sb_gquotino)));
  }

  /*
   * Return stat information for one inode.
   * Return 0 if ok, else errno.
   */
  int
  xfs_bulkstat_one_int(
  	struct xfs_mount	*mp,		/* mount point for filesystem */
  	xfs_ino_t		ino,		/* inode to get data for */
  	void __user		*buffer,	/* buffer to place output in */
  	int			ubsize,		/* size of buffer */
  	bulkstat_one_fmt_pf	formatter,	/* formatter, copy to user */

  	int			*ubused,	/* bytes used by me */
  	int			*stat)		/* BULKSTAT_RV_... */

  {

  	struct xfs_icdinode	*dic;		/* dinode core info pointer */
  	struct xfs_inode	*ip;		/* incore inode pointer */
  	struct inode		*inode;
  	struct xfs_bstat	*buf;		/* return buffer */
  	int			error = 0;	/* error value */
  
  	*stat = BULKSTAT_RV_NOTHING;
  
  	if (!buffer || xfs_internal_inum(mp, ino))
  		return XFS_ERROR(EINVAL);
  
  	buf = kmem_alloc(sizeof(*buf), KM_SLEEP | KM_MAYFAIL);
  	if (!buf)
  		return XFS_ERROR(ENOMEM);

  	error = xfs_iget(mp, NULL, ino,

  			 XFS_IGET_UNTRUSTED, XFS_ILOCK_SHARED, &ip);

  	if (error) {
  		*stat = BULKSTAT_RV_NOTHING;

  		goto out_free;

  	}
  
  	ASSERT(ip != NULL);

  	ASSERT(ip->i_imap.im_blkno != 0);

  
  	dic = &ip->i_d;

  	inode = VFS_I(ip);

  
  	/* xfs_iget returns the following without needing
  	 * further change.
  	 */
  	buf->bs_nlink = dic->di_nlink;

  	buf->bs_projid_lo = dic->di_projid_lo;
  	buf->bs_projid_hi = dic->di_projid_hi;

  	buf->bs_ino = ino;
  	buf->bs_mode = dic->di_mode;
  	buf->bs_uid = dic->di_uid;
  	buf->bs_gid = dic->di_gid;
  	buf->bs_size = dic->di_size;

  	/*

  	 * We need to read the timestamps from the Linux inode because
  	 * the VFS keeps writing directly into the inode structure instead
  	 * of telling us about the updates.

  	 */

  	buf->bs_atime.tv_sec = inode->i_atime.tv_sec;
  	buf->bs_atime.tv_nsec = inode->i_atime.tv_nsec;
  	buf->bs_mtime.tv_sec = inode->i_mtime.tv_sec;
  	buf->bs_mtime.tv_nsec = inode->i_mtime.tv_nsec;
  	buf->bs_ctime.tv_sec = inode->i_ctime.tv_sec;
  	buf->bs_ctime.tv_nsec = inode->i_ctime.tv_nsec;

  	buf->bs_xflags = xfs_ip2xflags(ip);
  	buf->bs_extsize = dic->di_extsize << mp->m_sb.sb_blocklog;
  	buf->bs_extents = dic->di_nextents;
  	buf->bs_gen = dic->di_gen;
  	memset(buf->bs_pad, 0, sizeof(buf->bs_pad));
  	buf->bs_dmevmask = dic->di_dmevmask;
  	buf->bs_dmstate = dic->di_dmstate;
  	buf->bs_aextents = dic->di_anextents;

  	buf->bs_forkoff = XFS_IFORK_BOFF(ip);

  
  	switch (dic->di_format) {
  	case XFS_DINODE_FMT_DEV:
  		buf->bs_rdev = ip->i_df.if_u2.if_rdev;
  		buf->bs_blksize = BLKDEV_IOSIZE;
  		buf->bs_blocks = 0;
  		break;
  	case XFS_DINODE_FMT_LOCAL:
  	case XFS_DINODE_FMT_UUID:
  		buf->bs_rdev = 0;
  		buf->bs_blksize = mp->m_sb.sb_blocksize;
  		buf->bs_blocks = 0;
  		break;
  	case XFS_DINODE_FMT_EXTENTS:
  	case XFS_DINODE_FMT_BTREE:
  		buf->bs_rdev = 0;
  		buf->bs_blksize = mp->m_sb.sb_blocksize;
  		buf->bs_blocks = dic->di_nblocks + ip->i_delayed_blks;
  		break;
  	}

  	xfs_iunlock(ip, XFS_ILOCK_SHARED);
  	IRELE(ip);

  	error = formatter(buffer, ubsize, ubused, buf);

  	if (!error)
  		*stat = BULKSTAT_RV_DIDONE;

   out_free:
  	kmem_free(buf);
  	return error;

  }

  /* Return 0 on success or positive error */

  STATIC int
  xfs_bulkstat_one_fmt(
  	void			__user *ubuffer,

  	int			ubsize,
  	int			*ubused,

  	const xfs_bstat_t	*buffer)
  {

  	if (ubsize < sizeof(*buffer))
  		return XFS_ERROR(ENOMEM);

  	if (copy_to_user(ubuffer, buffer, sizeof(*buffer)))

  		return XFS_ERROR(EFAULT);
  	if (ubused)
  		*ubused = sizeof(*buffer);
  	return 0;

  }

  int
  xfs_bulkstat_one(
  	xfs_mount_t	*mp,		/* mount point for filesystem */
  	xfs_ino_t	ino,		/* inode number to get data for */
  	void		__user *buffer,	/* buffer to place output in */
  	int		ubsize,		/* size of buffer */

  	int		*ubused,	/* bytes used by me */

  	int		*stat)		/* BULKSTAT_RV_... */
  {
  	return xfs_bulkstat_one_int(mp, ino, buffer, ubsize,

  				    xfs_bulkstat_one_fmt, ubused, stat);

  }

  #define XFS_BULKSTAT_UBLEFT(ubleft)	((ubleft) >= statstruct_size)

  /*

   * Return stat information in bulk (by-inode) for the filesystem.
   */
  int					/* error status */
  xfs_bulkstat(
  	xfs_mount_t		*mp,	/* mount point for filesystem */
  	xfs_ino_t		*lastinop, /* last inode returned */
  	int			*ubcountp, /* size of buffer/count returned */
  	bulkstat_one_pf		formatter, /* func that'd fill a single buf */

  	size_t			statstruct_size, /* sizeof struct filling */
  	char			__user *ubuffer, /* buffer with inode stats */

  	int			*done)	/* 1 if there are more stats to get */

  {
  	xfs_agblock_t		agbno=0;/* allocation group block number */
  	xfs_buf_t		*agbp;	/* agi header buffer */
  	xfs_agi_t		*agi;	/* agi header data */
  	xfs_agino_t		agino;	/* inode # in allocation group */
  	xfs_agnumber_t		agno;	/* allocation group number */
  	xfs_daddr_t		bno;	/* inode cluster start daddr */
  	int			chunkidx; /* current index into inode chunk */
  	int			clustidx; /* current index into inode cluster */
  	xfs_btree_cur_t		*cur;	/* btree cursor for ialloc btree */
  	int			end_of_ag; /* set if we've seen the ag end */
  	int			error;	/* error code */
  	int                     fmterror;/* bulkstat formatter result */

  	int			i;	/* loop index */
  	int			icount;	/* count of inodes good in irbuf */

  	size_t			irbsize; /* size of irec buffer in bytes */

  	xfs_ino_t		ino;	/* inode number (filesystem) */

  	xfs_inobt_rec_incore_t	*irbp;	/* current irec buffer pointer */
  	xfs_inobt_rec_incore_t	*irbuf;	/* start of irec buffer */
  	xfs_inobt_rec_incore_t	*irbufend; /* end of good irec buffer entries */

  	xfs_ino_t		lastino; /* last inode number returned */

  	int			nbcluster; /* # of blocks in a cluster */
  	int			nicluster; /* # of inodes in a cluster */
  	int			nimask;	/* mask for inode clusters */
  	int			nirbuf;	/* size of irbuf */
  	int			rval;	/* return value error code */
  	int			tmp;	/* result value from btree calls */
  	int			ubcount; /* size of user's buffer */
  	int			ubleft;	/* bytes left in user's buffer */
  	char			__user *ubufp;	/* pointer into user's buffer */
  	int			ubelem;	/* spaces used in user's buffer */
  	int			ubused;	/* bytes used by formatter */
  	xfs_buf_t		*bp;	/* ptr to on-disk inode cluster buf */

  
  	/*
  	 * Get the last inode value, see if there's nothing to do.
  	 */
  	ino = (xfs_ino_t)*lastinop;

  	lastino = ino;

  	agno = XFS_INO_TO_AGNO(mp, ino);
  	agino = XFS_INO_TO_AGINO(mp, ino);
  	if (agno >= mp->m_sb.sb_agcount ||
  	    ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
  		*done = 1;
  		*ubcountp = 0;
  		return 0;
  	}

  	if (!ubcountp || *ubcountp <= 0) {
  		return EINVAL;
  	}

  	ubcount = *ubcountp; /* statstruct's */
  	ubleft = ubcount * statstruct_size; /* bytes */
  	*ubcountp = ubelem = 0;
  	*done = 0;
  	fmterror = 0;
  	ubufp = ubuffer;
  	nicluster = mp->m_sb.sb_blocksize >= XFS_INODE_CLUSTER_SIZE(mp) ?
  		mp->m_sb.sb_inopblock :
  		(XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog);
  	nimask = ~(nicluster - 1);
  	nbcluster = nicluster >> mp->m_sb.sb_inopblog;

  	irbuf = kmem_zalloc_greedy(&irbsize, PAGE_SIZE, PAGE_SIZE * 4);
  	if (!irbuf)
  		return ENOMEM;

  	nirbuf = irbsize / sizeof(*irbuf);

  	/*
  	 * Loop over the allocation groups, starting from the last
  	 * inode returned; 0 means start of the allocation group.
  	 */
  	rval = 0;

  	while (XFS_BULKSTAT_UBLEFT(ubleft) && agno < mp->m_sb.sb_agcount) {
  		cond_resched();

  		bp = NULL;

  		error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);

  		if (error) {
  			/*
  			 * Skip this allocation group and go to the next one.
  			 */
  			agno++;
  			agino = 0;
  			continue;
  		}
  		agi = XFS_BUF_TO_AGI(agbp);
  		/*
  		 * Allocate and initialize a btree cursor for ialloc btree.
  		 */

  		cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno);

  		irbp = irbuf;
  		irbufend = irbuf + nirbuf;
  		end_of_ag = 0;
  		/*
  		 * If we're returning in the middle of an allocation group,
  		 * we need to get the remainder of the chunk we're in.
  		 */
  		if (agino > 0) {

  			xfs_inobt_rec_incore_t r;

  			/*
  			 * Lookup the inode chunk that this inode lives in.
  			 */

  			error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE,
  						 &tmp);

  			if (!error &&	/* no I/O error */
  			    tmp &&	/* lookup succeeded */
  					/* got the record, should always work */

  			    !(error = xfs_inobt_get_rec(cur, &r, &i)) &&

  			    i == 1 &&
  					/* this is the right chunk */

  			    agino < r.ir_startino + XFS_INODES_PER_CHUNK &&

  					/* lastino was not last in chunk */

  			    (chunkidx = agino - r.ir_startino + 1) <

  				    XFS_INODES_PER_CHUNK &&
  					/* there are some left allocated */

  			    xfs_inobt_maskn(chunkidx,

  				    XFS_INODES_PER_CHUNK - chunkidx) &
  				    ~r.ir_free) {

  				/*
  				 * Grab the chunk record.  Mark all the
  				 * uninteresting inodes (because they're
  				 * before our start point) free.
  				 */
  				for (i = 0; i < chunkidx; i++) {

  					if (XFS_INOBT_MASK(i) & ~r.ir_free)
  						r.ir_freecount++;

  				}

  				r.ir_free |= xfs_inobt_maskn(0, chunkidx);
  				irbp->ir_startino = r.ir_startino;
  				irbp->ir_freecount = r.ir_freecount;
  				irbp->ir_free = r.ir_free;

  				irbp++;

  				agino = r.ir_startino + XFS_INODES_PER_CHUNK;
  				icount = XFS_INODES_PER_CHUNK - r.ir_freecount;

  			} else {
  				/*
  				 * If any of those tests failed, bump the
  				 * inode number (just in case).
  				 */
  				agino++;
  				icount = 0;
  			}
  			/*
  			 * In any case, increment to the next record.
  			 */
  			if (!error)

  				error = xfs_btree_increment(cur, 0, &tmp);

  		} else {
  			/*
  			 * Start of ag.  Lookup the first inode chunk.
  			 */

  			error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &tmp);

  			icount = 0;
  		}
  		/*
  		 * Loop through inode btree records in this ag,
  		 * until we run out of inodes or space in the buffer.
  		 */
  		while (irbp < irbufend && icount < ubcount) {

  			xfs_inobt_rec_incore_t r;

  			/*
  			 * Loop as long as we're unable to read the
  			 * inode btree.
  			 */
  			while (error) {
  				agino += XFS_INODES_PER_CHUNK;
  				if (XFS_AGINO_TO_AGBNO(mp, agino) >=

  						be32_to_cpu(agi->agi_length))

  					break;

  				error = xfs_inobt_lookup(cur, agino,
  							 XFS_LOOKUP_GE, &tmp);

  				cond_resched();

  			}
  			/*
  			 * If ran off the end of the ag either with an error,
  			 * or the normal way, set end and stop collecting.
  			 */

  			if (error) {
  				end_of_ag = 1;
  				break;
  			}
  
  			error = xfs_inobt_get_rec(cur, &r, &i);
  			if (error || i == 0) {

  				end_of_ag = 1;
  				break;
  			}

  			/*
  			 * If this chunk has any allocated inodes, save it.

  			 * Also start read-ahead now for this chunk.

  			 */

  			if (r.ir_freecount < XFS_INODES_PER_CHUNK) {

  				/*
  				 * Loop over all clusters in the next chunk.
  				 * Do a readahead if there are any allocated
  				 * inodes in that cluster.
  				 */

  				agbno = XFS_AGINO_TO_AGBNO(mp, r.ir_startino);
  				for (chunkidx = 0;

  				     chunkidx < XFS_INODES_PER_CHUNK;
  				     chunkidx += nicluster,
  				     agbno += nbcluster) {

  					if (xfs_inobt_maskn(chunkidx, nicluster)
  							& ~r.ir_free)

  						xfs_btree_reada_bufs(mp, agno,
  							agbno, nbcluster);
  				}

  				irbp->ir_startino = r.ir_startino;
  				irbp->ir_freecount = r.ir_freecount;
  				irbp->ir_free = r.ir_free;

  				irbp++;

  				icount += XFS_INODES_PER_CHUNK - r.ir_freecount;

  			}
  			/*
  			 * Set agino to after this chunk and bump the cursor.
  			 */

  			agino = r.ir_startino + XFS_INODES_PER_CHUNK;

  			error = xfs_btree_increment(cur, 0, &tmp);

  			cond_resched();

  		}
  		/*
  		 * Drop the btree buffers and the agi buffer.
  		 * We can't hold any of the locks these represent
  		 * when calling iget.
  		 */
  		xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
  		xfs_buf_relse(agbp);
  		/*
  		 * Now format all the good inodes into the user's buffer.
  		 */
  		irbufend = irbp;
  		for (irbp = irbuf;

  		     irbp < irbufend && XFS_BULKSTAT_UBLEFT(ubleft); irbp++) {

  			/*

  			 * Now process this chunk of inodes.
  			 */

  			for (agino = irbp->ir_startino, chunkidx = clustidx = 0;

  			     XFS_BULKSTAT_UBLEFT(ubleft) &&

  				irbp->ir_freecount < XFS_INODES_PER_CHUNK;

  			     chunkidx++, clustidx++, agino++) {
  				ASSERT(chunkidx < XFS_INODES_PER_CHUNK);
  				/*
  				 * Recompute agbno if this is the
  				 * first inode of the cluster.
  				 *
  				 * Careful with clustidx.   There can be

  				 * multiple clusters per chunk, a single

  				 * cluster per chunk or a cluster that has
  				 * inodes represented from several different
  				 * chunks (if blocksize is large).
  				 *
  				 * Because of this, the starting clustidx is
  				 * initialized to zero in this loop but must
  				 * later be reset after reading in the cluster
  				 * buffer.
  				 */
  				if ((chunkidx & (nicluster - 1)) == 0) {
  					agbno = XFS_AGINO_TO_AGBNO(mp,

  							irbp->ir_startino) +

  						((chunkidx & nimask) >>
  						 mp->m_sb.sb_inopblog);

  				}

  				ino = XFS_AGINO_TO_INO(mp, agno, agino);
  				bno = XFS_AGB_TO_DADDR(mp, agno, agbno);

  				/*
  				 * Skip if this inode is free.
  				 */

  				if (XFS_INOBT_MASK(chunkidx) & irbp->ir_free) {
  					lastino = ino;

  					continue;

  				}

  				/*
  				 * Count used inodes as free so we can tell
  				 * when the chunk is used up.
  				 */

  				irbp->ir_freecount++;

  
  				/*
  				 * Get the inode and fill in a single buffer.

  				 */
  				ubused = statstruct_size;

  				error = formatter(mp, ino, ubufp, ubleft,

  						  &ubused, &fmterror);

  				if (fmterror == BULKSTAT_RV_NOTHING) {

  					if (error && error != ENOENT &&
  						error != EINVAL) {

  						ubleft = 0;

  						rval = error;
  						break;
  					}
  					lastino = ino;

  					continue;
  				}
  				if (fmterror == BULKSTAT_RV_GIVEUP) {
  					ubleft = 0;
  					ASSERT(error);
  					rval = error;
  					break;
  				}
  				if (ubufp)
  					ubufp += ubused;
  				ubleft -= ubused;
  				ubelem++;
  				lastino = ino;
  			}

  
  			cond_resched();

  		}
  
  		if (bp)
  			xfs_buf_relse(bp);
  
  		/*
  		 * Set up for the next loop iteration.
  		 */

  		if (XFS_BULKSTAT_UBLEFT(ubleft)) {

  			if (end_of_ag) {
  				agno++;
  				agino = 0;

  			} else
  				agino = XFS_INO_TO_AGINO(mp, lastino);

  		} else
  			break;
  	}
  	/*
  	 * Done, we're either out of filesystem or space to put the data.
  	 */

  	kmem_free_large(irbuf);

  	*ubcountp = ubelem;

  	/*
  	 * Found some inodes, return them now and return the error next time.
  	 */
  	if (ubelem)
  		rval = 0;

  	if (agno >= mp->m_sb.sb_agcount) {
  		/*
  		 * If we ran out of filesystem, mark lastino as off
  		 * the end of the filesystem, so the next call
  		 * will return immediately.
  		 */
  		*lastinop = (xfs_ino_t)XFS_AGINO_TO_INO(mp, agno, 0);
  		*done = 1;
  	} else
  		*lastinop = (xfs_ino_t)lastino;
  
  	return rval;
  }
  
  /*
   * Return stat information in bulk (by-inode) for the filesystem.
   * Special case for non-sequential one inode bulkstat.
   */
  int					/* error status */
  xfs_bulkstat_single(
  	xfs_mount_t		*mp,	/* mount point for filesystem */
  	xfs_ino_t		*lastinop, /* inode to return */
  	char			__user *buffer, /* buffer with inode stats */

  	int			*done)	/* 1 if there are more stats to get */

  {
  	int			count;	/* count value for bulkstat call */
  	int			error;	/* return value */
  	xfs_ino_t		ino;	/* filesystem inode number */
  	int			res;	/* result from bs1 */
  
  	/*
  	 * note that requesting valid inode numbers which are not allocated
  	 * to inodes will most likely cause xfs_itobp to generate warning
  	 * messages about bad magic numbers. This is ok. The fact that
  	 * the inode isn't actually an inode is handled by the
  	 * error check below. Done this way to make the usual case faster
  	 * at the expense of the error case.
  	 */
  
  	ino = (xfs_ino_t)*lastinop;

  	error = xfs_bulkstat_one(mp, ino, buffer, sizeof(xfs_bstat_t), 0, &res);

  	if (error) {
  		/*
  		 * Special case way failed, do it the "long" way
  		 * to see if that works.
  		 */
  		(*lastinop)--;
  		count = 1;
  		if (xfs_bulkstat(mp, lastinop, &count, xfs_bulkstat_one,

  				sizeof(xfs_bstat_t), buffer, done))

  			return error;
  		if (count == 0 || (xfs_ino_t)*lastinop != ino)
  			return error == EFSCORRUPTED ?
  				XFS_ERROR(EINVAL) : error;
  		else
  			return 0;
  	}
  	*done = 0;
  	return 0;
  }

  int
  xfs_inumbers_fmt(
  	void			__user *ubuffer, /* buffer to write to */
  	const xfs_inogrp_t	*buffer,	/* buffer to read from */
  	long			count,		/* # of elements to read */
  	long			*written)	/* # of bytes written */
  {
  	if (copy_to_user(ubuffer, buffer, count * sizeof(*buffer)))
  		return -EFAULT;
  	*written = count * sizeof(*buffer);
  	return 0;
  }

  /*
   * Return inode number table for the filesystem.
   */
  int					/* error status */
  xfs_inumbers(
  	xfs_mount_t	*mp,		/* mount point for filesystem */
  	xfs_ino_t	*lastino,	/* last inode returned */
  	int		*count,		/* size of buffer/count returned */

  	void		__user *ubuffer,/* buffer with inode descriptions */
  	inumbers_fmt_pf	formatter)

  {
  	xfs_buf_t	*agbp;
  	xfs_agino_t	agino;
  	xfs_agnumber_t	agno;
  	int		bcount;
  	xfs_inogrp_t	*buffer;
  	int		bufidx;
  	xfs_btree_cur_t	*cur;
  	int		error;

  	xfs_inobt_rec_incore_t r;

  	int		i;
  	xfs_ino_t	ino;
  	int		left;
  	int		tmp;
  
  	ino = (xfs_ino_t)*lastino;
  	agno = XFS_INO_TO_AGNO(mp, ino);
  	agino = XFS_INO_TO_AGINO(mp, ino);
  	left = *count;
  	*count = 0;

  	bcount = MIN(left, (int)(PAGE_SIZE / sizeof(*buffer)));

  	buffer = kmem_alloc(bcount * sizeof(*buffer), KM_SLEEP);
  	error = bufidx = 0;
  	cur = NULL;
  	agbp = NULL;
  	while (left > 0 && agno < mp->m_sb.sb_agcount) {
  		if (agbp == NULL) {

  			error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);

  			if (error) {
  				/*
  				 * If we can't read the AGI of this ag,
  				 * then just skip to the next one.
  				 */
  				ASSERT(cur == NULL);
  				agbp = NULL;
  				agno++;
  				agino = 0;
  				continue;
  			}

  			cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno);

  			error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_GE,
  						 &tmp);

  			if (error) {
  				xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
  				cur = NULL;
  				xfs_buf_relse(agbp);
  				agbp = NULL;
  				/*

  				 * Move up the last inode in the current

  				 * chunk.  The lookup_ge will always get
  				 * us the first inode in the next chunk.
  				 */
  				agino += XFS_INODES_PER_CHUNK - 1;
  				continue;
  			}
  		}

  		error = xfs_inobt_get_rec(cur, &r, &i);
  		if (error || i == 0) {

  			xfs_buf_relse(agbp);
  			agbp = NULL;
  			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
  			cur = NULL;
  			agno++;
  			agino = 0;
  			continue;
  		}

  		agino = r.ir_startino + XFS_INODES_PER_CHUNK - 1;
  		buffer[bufidx].xi_startino =
  			XFS_AGINO_TO_INO(mp, agno, r.ir_startino);
  		buffer[bufidx].xi_alloccount =
  			XFS_INODES_PER_CHUNK - r.ir_freecount;
  		buffer[bufidx].xi_allocmask = ~r.ir_free;

  		bufidx++;
  		left--;
  		if (bufidx == bcount) {

  			long written;
  			if (formatter(ubuffer, buffer, bufidx, &written)) {

  				error = XFS_ERROR(EFAULT);
  				break;
  			}

  			ubuffer += written;

  			*count += bufidx;
  			bufidx = 0;
  		}
  		if (left) {

  			error = xfs_btree_increment(cur, 0, &tmp);

  			if (error) {
  				xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
  				cur = NULL;
  				xfs_buf_relse(agbp);
  				agbp = NULL;
  				/*
  				 * The agino value has already been bumped.
  				 * Just try to skip up to it.
  				 */
  				agino += XFS_INODES_PER_CHUNK;
  				continue;
  			}
  		}
  	}
  	if (!error) {
  		if (bufidx) {

  			long written;
  			if (formatter(ubuffer, buffer, bufidx, &written))

  				error = XFS_ERROR(EFAULT);
  			else
  				*count += bufidx;
  		}
  		*lastino = XFS_AGINO_TO_INO(mp, agno, agino);
  	}

  	kmem_free(buffer);

  	if (cur)
  		xfs_btree_del_cursor(cur, (error ? XFS_BTREE_ERROR :
  					   XFS_BTREE_NOERROR));
  	if (agbp)
  		xfs_buf_relse(agbp);
  	return error;
  }