xfs: fix error handling at xfs_inumbers

PATCH In review Jeff Liu 1 participant 2 messages Jun 3, 2014 – Jun 4, 2014 XFS filesystem

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Jeff Liu

author

2014-06-03 09:18 UTC #0 lore raw

PATCH v3 4/10 xfs: fix error handling at xfs_inumbers

From: Jie Liu <[email protected]>

To fetch the file system number tables, we currently just ignore the errors and proceed to loop over the next AG or bump agino to the next chunk in case of btree operations failed, that is not properly because those errors might hint us potential file system problems.

This patch rework xfs_inumbers() to handle the btree operation errors as well as the loop conditions.

Signed-off-by Jie Liu <[email protected]>

---
 fs/xfs/xfs_itable.c | 91 ++++++++++++++++++++++-------------------------------
 1 file changed, 37 insertions(+), 54 deletions(-)

fs/xfs/xfs_itable.c +37 ~~-54~~

index dd68696..693e787 100644
@@ -550,61 +550,40 @@ xfs_inumbers(
 
 	bcount = MIN(left, (int)(PAGE_SIZE / sizeof(*buffer)));
 	buffer = kmem_alloc(bcount * sizeof(*buffer), KM_SLEEP);
-	while (left > 0 && agno < mp->m_sb.sb_agcount) {
+	do {
 		struct xfs_inobt_rec_incore	r;
 		int				stat;
 
-		if (agbp == NULL) {
+		if (!agbp) {
 			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;
-			}
+			if (error)
+				break;
+
 			cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno,
 						    XFS_BTNUM_INO);
 			error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_GE,
 						 &stat);
-			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;
-			}
+			if (error)
+				break;
+			if (!stat)
+				goto next_ag;
 		}
+
 		error = xfs_inobt_get_rec(cur, &r, &stat);
-		if (error || stat == 0) {
-			xfs_buf_relse(agbp);
-			agbp = NULL;
-			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
-			cur = NULL;
-			agno++;
-			agino = 0;
-			continue;
-		}
+		if (error)
+			break;
+		if (!stat)
+			goto next_ag;
+
 		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) {
+		if (++bufidx == bcount) {
 			long written;
+
 			error = formatter(ubuffer, buffer, bufidx, &written);
 			if (error)
 				break;

@@ -612,22 +591,24 @@ xfs_inumbers(
 			*count += bufidx;
 			bufidx = 0;
 		}
-		if (left) {
-			error = xfs_btree_increment(cur, 0, &stat);
-			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 (--left)
+			break;
+
+		error = xfs_btree_increment(cur, 0, &stat);
+		if (error)
+			break;
+		if (stat)
+			continue;
+
+next_ag:
+		xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
+		cur = NULL;
+		xfs_buf_relse(agbp);
+		agbp = NULL;
+		agno++;
+		agino = 0;
+	} while (++agno < mp->m_sb.sb_agcount);
+
 	if (!error) {
 		if (bufidx) {
 			long written;

@@ -638,11 +619,13 @@ xfs_inumbers(
 		}
 		*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;
 }

Signature · 6 lines

1.8.3.2

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Jeff Liu

author

2014-06-04 12:41 UTC #1 lore raw

Sorry, there is an issue in this patch, an updated version was shown as following,

From: Jie Liu <[email protected]>

This patch rework xfs_inumbers() to handle the btree operation errors as well as the loop conditions.

Signed-off-by Jie Liu <[email protected]>

---
 fs/xfs/xfs_itable.c | 96 ++++++++++++++++++++++-------------------------------
 1 file changed, 39 insertions(+), 57 deletions(-)

fs/xfs/xfs_itable.c +39 ~~-57~~

index dd68696..4b41910 100644
@@ -536,7 +536,7 @@ xfs_inumbers(
 	xfs_agnumber_t		agno = XFS_INO_TO_AGNO(mp, *lastino);
 	xfs_agino_t		agino = XFS_INO_TO_AGINO(mp, *lastino);
 	struct xfs_btree_cur	*cur = NULL;
-	xfs_buf_t		*agbp = NULL;
+	struct xfs_buf		*agbp = NULL;
 	struct xfs_inogrp	*buffer;
 	int			bcount;
 	int			left = *count;

@@ -550,61 +550,40 @@ xfs_inumbers(
 
 	bcount = MIN(left, (int)(PAGE_SIZE / sizeof(*buffer)));
 	buffer = kmem_alloc(bcount * sizeof(*buffer), KM_SLEEP);
-	while (left > 0 && agno < mp->m_sb.sb_agcount) {
+	do {
 		struct xfs_inobt_rec_incore	r;
 		int				stat;
 
-		if (agbp == NULL) {
+		if (!agbp) {
 			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;
-			}
+			if (error)
+				break;
+
 			cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno,
 						    XFS_BTNUM_INO);
 			error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_GE,
 						 &stat);
-			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;
-			}
+			if (error)
+				break;
+			if (!stat)
+				goto next_ag;
 		}
+
 		error = xfs_inobt_get_rec(cur, &r, &stat);
-		if (error || stat == 0) {
-			xfs_buf_relse(agbp);
-			agbp = NULL;
-			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
-			cur = NULL;
-			agno++;
-			agino = 0;
-			continue;
-		}
+		if (error)
+			break;
+		if (!stat)
+			goto next_ag;
+
 		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 (++bufidx == bcount) {
+			long	written;
+
 			error = formatter(ubuffer, buffer, bufidx, &written);
 			if (error)
 				break;

@@ -612,25 +591,26 @@ xfs_inumbers(
 			*count += bufidx;
 			bufidx = 0;
 		}
-		if (left) {
-			error = xfs_btree_increment(cur, 0, &stat);
-			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 (!--left)
+			break;
+
+		error = xfs_btree_increment(cur, 0, &stat);
+		if (error)
+			break;
+		if (stat)
+			continue;
+
+next_ag:
+		xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
+		cur = NULL;
+		xfs_buf_relse(agbp);
+		agbp = NULL;
+		agino = 0;
+	} while (++agno < mp->m_sb.sb_agcount);
+
 	if (!error) {
 		if (bufidx) {
-			long written;
+			long	written;
 
 			error = formatter(ubuffer, buffer, bufidx, &written);
 			if (!error)

@@ -638,11 +618,13 @@ xfs_inumbers(
 		}
 		*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;
 }

Signature · 6 lines

1.8.3.2

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http://oss.sgi.com/mailman/listinfo/xfs