1 files changed, 132 insertions, 296 deletions

diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
index 72af0c8cbc92..118ff1b686c1 100644
--- a/fs/xfs/xfs_itable.c
+++ b/fs/xfs/xfs_itable.c
@@ -14,46 +14,66 @@
 #include "xfs_btree.h"
 #include "xfs_ialloc.h"
 #include "xfs_ialloc_btree.h"
+#include "xfs_iwalk.h"
 #include "xfs_itable.h"
 #include "xfs_error.h"
 #include "xfs_icache.h"
 #include "xfs_health.h"
-#include "xfs_iwalk.h"
 
 /*
- * Return stat information for one inode.
- * Return 0 if ok, else errno.
+ * Bulk Stat
+ * =========
+ *
+ * Use the inode walking functions to fill out struct xfs_bstat for every
+ * allocated inode, then pass the stat information to some externally provided
+ * iteration function.
  */
-int
+
+struct xfs_bstat_chunk {
+	bulkstat_one_fmt_pf	formatter;
+	struct xfs_ibulk	*breq;
+	struct xfs_bstat	*buf;
+};
+
+/*
+ * Fill out the bulkstat info for a single inode and report it somewhere.
+ *
+ * bc->breq->lastino is effectively the inode cursor as we walk through the
+ * filesystem.  Therefore, we update it any time we need to move the cursor
+ * forward, regardless of whether or not we're sending any bstat information
+ * back to userspace.  If the inode is internal metadata or, has been freed
+ * out from under us, we just simply keep going.
+ *
+ * However, if any other type of error happens we want to stop right where we
+ * are so that userspace will call back with exact number of the bad inode and
+ * we can send back an error code.
+ *
+ * Note that if the formatter tells us there's no space left in the buffer we
+ * move the cursor forward and abort the walk.
+ */
+STATIC 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_mount	*mp,
+	struct xfs_trans	*tp,
+	xfs_ino_t		ino,
+	struct xfs_bstat_chunk	*bc)
 {
 	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 */
+	struct xfs_bstat	*buf = bc->buf;
+	int			error = -EINVAL;
 
-	*stat = BULKSTAT_RV_NOTHING;
+	if (xfs_internal_inum(mp, ino))
+		goto out_advance;
 
-	if (!buffer || xfs_internal_inum(mp, ino))
-		return -EINVAL;
-
-	buf = kmem_zalloc(sizeof(*buf), KM_SLEEP | KM_MAYFAIL);
-	if (!buf)
-		return -ENOMEM;
-
-	error = xfs_iget(mp, NULL, ino,
+	error = xfs_iget(mp, tp, ino,
 			 (XFS_IGET_DONTCACHE | XFS_IGET_UNTRUSTED),
 			 XFS_ILOCK_SHARED, &ip);
+	if (error == -ENOENT || error == -EINVAL)
+		goto out_advance;
 	if (error)
-		goto out_free;
+		goto out;
 
 	ASSERT(ip != NULL);
 	ASSERT(ip->i_imap.im_blkno != 0);
@@ -118,43 +138,54 @@ xfs_bulkstat_one_int(
 	xfs_iunlock(ip, XFS_ILOCK_SHARED);
 	xfs_irele(ip);
 
-	error = formatter(buffer, ubsize, ubused, buf);
-	if (!error)
-		*stat = BULKSTAT_RV_DIDONE;
+	error = bc->formatter(bc->breq, buf);
+	if (error == XFS_IBULK_ABORT)
+		goto out_advance;
+	if (error)
+		goto out;
 
- out_free:
-	kmem_free(buf);
+out_advance:
+	/*
+	 * Advance the cursor to the inode that comes after the one we just
+	 * looked at.  We want the caller to move along if the bulkstat
+	 * information was copied successfully; if we tried to grab the inode
+	 * but it's no longer allocated; or if it's internal metadata.
+	 */
+	bc->breq->startino = ino + 1;
+out:
 	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 -ENOMEM;
-	if (copy_to_user(ubuffer, buffer, sizeof(*buffer)))
-		return -EFAULT;
-	if (ubused)
-		*ubused = sizeof(*buffer);
-	return 0;
-}
-
+/* Bulkstat a single inode. */
 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_... */
+	struct xfs_ibulk	*breq,
+	bulkstat_one_fmt_pf	formatter)
 {
-	return xfs_bulkstat_one_int(mp, ino, buffer, ubsize,
-				    xfs_bulkstat_one_fmt, ubused, stat);
+	struct xfs_bstat_chunk	bc = {
+		.formatter	= formatter,
+		.breq		= breq,
+	};
+	int			error;
+
+	ASSERT(breq->icount == 1);
+
+	bc.buf = kmem_zalloc(sizeof(struct xfs_bstat), KM_SLEEP | KM_MAYFAIL);
+	if (!bc.buf)
+		return -ENOMEM;
+
+	error = xfs_bulkstat_one_int(breq->mp, NULL, breq->startino, &bc);
+
+	kmem_free(bc.buf);
+
+	/*
+	 * If we reported one inode to userspace then we abort because we hit
+	 * the end of the buffer.  Don't leak that back to userspace.
+	 */
+	if (error == XFS_IWALK_ABORT)
+		error = 0;
+
+	return error;
 }
 
 /*
@@ -250,256 +281,69 @@ xfs_bulkstat_grab_ichunk(
 
 #define XFS_BULKSTAT_UBLEFT(ubleft)	((ubleft) >= statstruct_size)
 
-struct xfs_bulkstat_agichunk {
-	char		__user **ac_ubuffer;/* pointer into user's buffer */
-	int		ac_ubleft;	/* bytes left in user's buffer */
-	int		ac_ubelem;	/* spaces used in user's buffer */
-};
-
-/*
- * Process inodes in chunk with a pointer to a formatter function
- * that will iget the inode and fill in the appropriate structure.
- */
 static int
-xfs_bulkstat_ag_ichunk(
-	struct xfs_mount		*mp,
-	xfs_agnumber_t			agno,
-	struct xfs_inobt_rec_incore	*irbp,
-	bulkstat_one_pf			formatter,
-	size_t				statstruct_size,
-	struct xfs_bulkstat_agichunk	*acp,
-	xfs_agino_t			*last_agino)
+xfs_bulkstat_iwalk(
+	struct xfs_mount	*mp,
+	struct xfs_trans	*tp,
+	xfs_ino_t		ino,
+	void			*data)
 {
-	char				__user **ubufp = acp->ac_ubuffer;
-	int				chunkidx;
-	int				error = 0;
-	xfs_agino_t			agino = irbp->ir_startino;
-
-	for (chunkidx = 0; chunkidx < XFS_INODES_PER_CHUNK;
-	     chunkidx++, agino++) {
-		int		fmterror;
-		int		ubused;
-
-		/* inode won't fit in buffer, we are done */
-		if (acp->ac_ubleft < statstruct_size)
-			break;
-
-		/* Skip if this inode is free */
-		if (XFS_INOBT_MASK(chunkidx) & irbp->ir_free)
-			continue;
-
-		/* Get the inode and fill in a single buffer */
-		ubused = statstruct_size;
-		error = formatter(mp, XFS_AGINO_TO_INO(mp, agno, agino),
-				  *ubufp, acp->ac_ubleft, &ubused, &fmterror);
-
-		if (fmterror == BULKSTAT_RV_GIVEUP ||
-		    (error && error != -ENOENT && error != -EINVAL)) {
-			acp->ac_ubleft = 0;
-			ASSERT(error);
-			break;
-		}
-
-		/* be careful not to leak error if at end of chunk */
-		if (fmterror == BULKSTAT_RV_NOTHING || error) {
-			error = 0;
-			continue;
-		}
-
-		*ubufp += ubused;
-		acp->ac_ubleft -= ubused;
-		acp->ac_ubelem++;
-	}
-
-	/*
-	 * Post-update *last_agino. At this point, agino will always point one
-	 * inode past the last inode we processed successfully. Hence we
-	 * substract that inode when setting the *last_agino cursor so that we
-	 * return the correct cookie to userspace. On the next bulkstat call,
-	 * the inode under the lastino cookie will be skipped as we have already
-	 * processed it here.
-	 */
-	*last_agino = agino - 1;
+	int			error;
 
+	error = xfs_bulkstat_one_int(mp, tp, ino, data);
+	/* bulkstat just skips over missing inodes */
+	if (error == -ENOENT || error == -EINVAL)
+		return 0;
 	return error;
 }
 
 /*
- * Return stat information in bulk (by-inode) for the filesystem.
+ * Check the incoming lastino parameter.
+ *
+ * We allow any inode value that could map to physical space inside the
+ * filesystem because if there are no inodes there, bulkstat moves on to the
+ * next chunk.  In other words, the magic agino value of zero takes us to the
+ * first chunk in the AG, and an agino value past the end of the AG takes us to
+ * the first chunk in the next AG.
+ *
+ * Therefore we can end early if the requested inode is beyond the end of the
+ * filesystem or doesn't map properly.
  */
-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 */
+static inline bool
+xfs_bulkstat_already_done(
+	struct xfs_mount	*mp,
+	xfs_ino_t		startino)
 {
-	xfs_buf_t		*agbp;	/* agi header buffer */
-	xfs_agino_t		agino;	/* inode # in allocation group */
-	xfs_agnumber_t		agno;	/* allocation group number */
-	xfs_btree_cur_t		*cur;	/* btree cursor for ialloc btree */
-	xfs_inobt_rec_incore_t	*irbuf;	/* start of irec buffer */
-	int			nirbuf;	/* size of irbuf */
-	int			ubcount; /* size of user's buffer */
-	struct xfs_bulkstat_agichunk ac;
-	int			error = 0;
+	xfs_agnumber_t		agno = XFS_INO_TO_AGNO(mp, startino);
+	xfs_agino_t		agino = XFS_INO_TO_AGINO(mp, startino);
 
-	/*
-	 * Get the last inode value, see if there's nothing to do.
-	 */
-	agno = XFS_INO_TO_AGNO(mp, *lastinop);
-	agino = XFS_INO_TO_AGINO(mp, *lastinop);
-	if (agno >= mp->m_sb.sb_agcount ||
-	    *lastinop != XFS_AGINO_TO_INO(mp, agno, agino)) {
-		*done = 1;
-		*ubcountp = 0;
-		return 0;
-	}
+	return agno >= mp->m_sb.sb_agcount ||
+	       startino != XFS_AGINO_TO_INO(mp, agno, agino);
+}
 
-	ubcount = *ubcountp; /* statstruct's */
-	ac.ac_ubuffer = &ubuffer;
-	ac.ac_ubleft = ubcount * statstruct_size; /* bytes */;
-	ac.ac_ubelem = 0;
+/* Return stat information in bulk (by-inode) for the filesystem. */
+int
+xfs_bulkstat(
+	struct xfs_ibulk	*breq,
+	bulkstat_one_fmt_pf	formatter)
+{
+	struct xfs_bstat_chunk	bc = {
+		.formatter	= formatter,
+		.breq		= breq,
+	};
+	int			error;
 
-	*ubcountp = 0;
-	*done = 0;
+	if (xfs_bulkstat_already_done(breq->mp, breq->startino))
+		return 0;
 
-	irbuf = kmem_zalloc_large(PAGE_SIZE * 4, KM_SLEEP);
-	if (!irbuf)
+	bc.buf = kmem_zalloc(sizeof(struct xfs_bstat), KM_SLEEP | KM_MAYFAIL);
+	if (!bc.buf)
 		return -ENOMEM;
-	nirbuf = (PAGE_SIZE * 4) / sizeof(*irbuf);
-
-	/*
-	 * Loop over the allocation groups, starting from the last
-	 * inode returned; 0 means start of the allocation group.
-	 */
-	while (agno < mp->m_sb.sb_agcount) {
-		struct xfs_inobt_rec_incore	*irbp = irbuf;
-		struct xfs_inobt_rec_incore	*irbufend = irbuf + nirbuf;
-		bool				end_of_ag = false;
-		int				icount = 0;
-		int				stat;
-
-		error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
-		if (error)
-			break;
-		/*
-		 * Allocate and initialize a btree cursor for ialloc btree.
-		 */
-		cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno,
-					    XFS_BTNUM_INO);
-		if (agino > 0) {
-			/*
-			 * In the middle of an allocation group, we need to get
-			 * the remainder of the chunk we're in.
-			 */
-			struct xfs_inobt_rec_incore	r;
-
-			error = xfs_bulkstat_grab_ichunk(cur, agino, &icount, &r);
-			if (error)
-				goto del_cursor;
-			if (icount) {
-				irbp->ir_startino = r.ir_startino;
-				irbp->ir_holemask = r.ir_holemask;
-				irbp->ir_count = r.ir_count;
-				irbp->ir_freecount = r.ir_freecount;
-				irbp->ir_free = r.ir_free;
-				irbp++;
-			}
-			/* Increment to the next record */
-			error = xfs_btree_increment(cur, 0, &stat);
-		} else {
-			/* Start of ag.  Lookup the first inode chunk */
-			error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &stat);
-		}
-		if (error || stat == 0) {
-			end_of_ag = true;
-			goto del_cursor;
-		}
-
-		/*
-		 * Loop through inode btree records in this ag,
-		 * until we run out of inodes or space in the buffer.
-		 */
-		while (irbp < irbufend && icount < ubcount) {
-			struct xfs_inobt_rec_incore	r;
-
-			error = xfs_inobt_get_rec(cur, &r, &stat);
-			if (error || stat == 0) {
-				end_of_ag = true;
-				goto del_cursor;
-			}
-
-			/*
-			 * If this chunk has any allocated inodes, save it.
-			 * Also start read-ahead now for this chunk.
-			 */
-			if (r.ir_freecount < r.ir_count) {
-				xfs_bulkstat_ichunk_ra(mp, agno, &r);
-				irbp->ir_startino = r.ir_startino;
-				irbp->ir_holemask = r.ir_holemask;
-				irbp->ir_count = r.ir_count;
-				irbp->ir_freecount = r.ir_freecount;
-				irbp->ir_free = r.ir_free;
-				irbp++;
-				icount += r.ir_count - r.ir_freecount;
-			}
-			error = xfs_btree_increment(cur, 0, &stat);
-			if (error || stat == 0) {
-				end_of_ag = true;
-				goto del_cursor;
-			}
-			cond_resched();
-		}
-
-		/*
-		 * Drop the btree buffers and the agi buffer as we can't hold any
-		 * of the locks these represent when calling iget. If there is a
-		 * pending error, then we are done.
-		 */
-del_cursor:
-		xfs_btree_del_cursor(cur, error);
-		xfs_buf_relse(agbp);
-		if (error)
-			break;
-		/*
-		 * Now format all the good inodes into the user's buffer. The
-		 * call to xfs_bulkstat_ag_ichunk() sets up the agino pointer
-		 * for the next loop iteration.
-		 */
-		irbufend = irbp;
-		for (irbp = irbuf;
-		     irbp < irbufend && ac.ac_ubleft >= statstruct_size;
-		     irbp++) {
-			error = xfs_bulkstat_ag_ichunk(mp, agno, irbp,
-					formatter, statstruct_size, &ac,
-					&agino);
-			if (error)
-				break;
 
-			cond_resched();
-		}
+	error = xfs_iwalk(breq->mp, NULL, breq->startino, xfs_bulkstat_iwalk,
+			breq->icount, &bc);
 
-		/*
-		 * If we've run out of space or had a formatting error, we
-		 * are now done
-		 */
-		if (ac.ac_ubleft < statstruct_size || error)
-			break;
-
-		if (end_of_ag) {
-			agno++;
-			agino = 0;
-		}
-	}
-	/*
-	 * Done, we're either out of filesystem or space to put the data.
-	 */
-	kmem_free(irbuf);
-	*ubcountp = ac.ac_ubelem;
+	kmem_free(bc.buf);
 
 	/*
 	 * We found some inodes, so clear the error status and return them.
@@ -508,17 +352,9 @@ del_cursor:
 	 * triggered again and propagated to userspace as there will be no
 	 * formatted inodes in the buffer.
 	 */
-	if (ac.ac_ubelem)
+	if (breq->ocount > 0)
 		error = 0;
 
-	/*
-	 * If we ran out of filesystem, lastino will point off the end of
-	 * the filesystem so the next call will return immediately.
-	 */
-	*lastinop = XFS_AGINO_TO_INO(mp, agno, agino);
-	if (agno >= mp->m_sb.sb_agcount)
-		*done = 1;
-
 	return error;
 }