[XFS] Fix CI lookup in leaf-form directories

Instead of comparing buffer pointers, compare buffer block numbers and don't keep buff SGI-PV: 983564 SGI-Modid: xfs-linux-melb:xfs-kern:31346a Signed-off-by: Barry Naujok <bnaujok@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

[XFS] Fix CI lookup in leaf-form directories
Instead of comparing buffer pointers, compare buffer block numbers and don't keep buff SGI-PV: 983564 SGI-Modid: xfs-linux-melb:xfs-kern:31346a Signed-off-by: Barry Naujok <bnaujok@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Barry Naujok · Niv Sardi
1 parent f9e09f095f
Showing 1 changed file with 25 additions and 24 deletions Side-by-side Diff
fs/xfs/xfs_dir2_leaf.c
@@ -1321,8 +1321,8 @@
 	int			*indexp,	/* out: index in leaf block */
 	xfs_dabuf_t		**dbpp)		/* out: data buffer */
 {
-	xfs_dir2_db_t		curdb;		/* current data block number */
-	xfs_dabuf_t		*dbp;		/* data buffer */
+	xfs_dir2_db_t		curdb = -1;	/* current data block number */
+	xfs_dabuf_t		*dbp = NULL;	/* data buffer */
 	xfs_dir2_data_entry_t	*dep;		/* data entry */
 	xfs_inode_t		*dp;		/* incore directory inode */
 	int			error;		/* error return code */
@@ -1333,7 +1333,7 @@
 	xfs_mount_t		*mp;		/* filesystem mount point */
 	xfs_dir2_db_t		newdb;		/* new data block number */
 	xfs_trans_t		*tp;		/* transaction pointer */
-	xfs_dabuf_t		*cbp;		/* case match data buffer */
+	xfs_dir2_db_t		cidb = -1;	/* case match data block no. */
 	enum xfs_dacmp		cmp;		/* name compare result */
  
 	dp = args->dp;
  
@@ -1342,11 +1342,10 @@
 	/*
 	 * Read the leaf block into the buffer.
 	 */
-	if ((error =
-	    xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
-		    XFS_DATA_FORK))) {
+	error = xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
+							XFS_DATA_FORK);
+	if (error)
 		return error;
-	}
 	*lbpp = lbp;
 	leaf = lbp->data;
 	xfs_dir2_leaf_check(dp, lbp);
@@ -1358,9 +1357,7 @@
 	 * Loop over all the entries with the right hash value
 	 * looking to match the name.
 	 */
-	cbp = NULL;
-	for (lep = &leaf->ents[index], dbp = NULL, curdb = -1;
-				index < be16_to_cpu(leaf->hdr.count) &&
+	for (lep = &leaf->ents[index]; index < be16_to_cpu(leaf->hdr.count) &&
 				be32_to_cpu(lep->hashval) == args->hashval;
 				lep++, index++) {
 		/*
@@ -1377,7 +1374,7 @@
 		 * need to pitch the old one and read the new one.
 		 */
 		if (newdb != curdb) {
-			if (dbp != cbp)
+			if (dbp)
 				xfs_da_brelse(tp, dbp);
 			error = xfs_da_read_buf(tp, dp,
 						xfs_dir2_db_to_da(mp, newdb),
  
  
  
  
  
  
@@ -1403,35 +1400,39 @@
 		if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
 			args->cmpresult = cmp;
 			*indexp = index;
-			/*
-			 * case exact match: release the stored CI buffer if it
-			 * exists and return the current buffer.
-			 */
+			/* case exact match: return the current buffer. */
 			if (cmp == XFS_CMP_EXACT) {
-				if (cbp && cbp != dbp)
-					xfs_da_brelse(tp, cbp);
 				*dbpp = dbp;
 				return 0;
 			}
-			cbp = dbp;
+			cidb = curdb;
 		}
 	}
 	ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 	/*
-	 * Here, we can only be doing a lookup (not a rename or replace).
-	 * If a case-insensitive match was found earlier, release the current
-	 * buffer and return the stored CI matching buffer.
+	 * Here, we can only be doing a lookup (not a rename or remove).
+	 * If a case-insensitive match was found earlier, re-read the
+	 * appropriate data block if required and return it.
 	 */
 	if (args->cmpresult == XFS_CMP_CASE) {
-		if (cbp != dbp)
+		ASSERT(cidb != -1);
+		if (cidb != curdb) {
 			xfs_da_brelse(tp, dbp);
-		*dbpp = cbp;
+			error = xfs_da_read_buf(tp, dp,
+						xfs_dir2_db_to_da(mp, cidb),
+						-1, &dbp, XFS_DATA_FORK);
+			if (error) {
+				xfs_da_brelse(tp, lbp);
+				return error;
+			}
+		}
+		*dbpp = dbp;
 		return 0;
 	}
 	/*
 	 * No match found, return ENOENT.
 	 */
-	ASSERT(cbp == NULL);
+	ASSERT(cidb == -1);
 	if (dbp)
 		xfs_da_brelse(tp, dbp);
 	xfs_da_brelse(tp, lbp);
...	...	@@ -1321,8 +1321,8 @@
1321	1321	int indexp, / out: index in leaf block */
1322	1322	xfs_dabuf_t *dbpp) / out: data buffer */
1323	1323	{
1324		- xfs_dir2_db_t curdb; /* current data block number */
1325		- xfs_dabuf_t dbp; / data buffer */
	1324	+ xfs_dir2_db_t curdb = -1; /* current data block number */
	1325	+ xfs_dabuf_t dbp = NULL; / data buffer */
1326	1326	xfs_dir2_data_entry_t dep; / data entry */
1327	1327	xfs_inode_t dp; / incore directory inode */
1328	1328	int error; /* error return code */
...	...	@@ -1333,7 +1333,7 @@
1333	1333	xfs_mount_t mp; / filesystem mount point */
1334	1334	xfs_dir2_db_t newdb; /* new data block number */
1335	1335	xfs_trans_t tp; / transaction pointer */
1336		- xfs_dabuf_t cbp; / case match data buffer */
	1336	+ xfs_dir2_db_t cidb = -1; /* case match data block no. */
1337	1337	enum xfs_dacmp cmp; /* name compare result */
1338	1338
1339	1339	dp = args->dp;
1340	1340
...	...	@@ -1342,11 +1342,10 @@
1342	1342	/*
1343	1343	* Read the leaf block into the buffer.
1344	1344	*/
1345		- if ((error =
1346		- xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
1347		- XFS_DATA_FORK))) {
	1345	+ error = xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
	1346	+ XFS_DATA_FORK);
	1347	+ if (error)
1348	1348	return error;
1349		- }
1350	1349	*lbpp = lbp;
1351	1350	leaf = lbp->data;
1352	1351	xfs_dir2_leaf_check(dp, lbp);
...	...	@@ -1358,9 +1357,7 @@
1358	1357	* Loop over all the entries with the right hash value
1359	1358	* looking to match the name.
1360	1359	*/
1361		- cbp = NULL;
1362		- for (lep = &leaf->ents[index], dbp = NULL, curdb = -1;
1363		- index < be16_to_cpu(leaf->hdr.count) &&
	1360	+ for (lep = &leaf->ents[index]; index < be16_to_cpu(leaf->hdr.count) &&
1364	1361	be32_to_cpu(lep->hashval) == args->hashval;
1365	1362	lep++, index++) {
1366	1363	/*
...	...	@@ -1377,7 +1374,7 @@
1377	1374	* need to pitch the old one and read the new one.
1378	1375	*/
1379	1376	if (newdb != curdb) {
1380		- if (dbp != cbp)
	1377	+ if (dbp)
1381	1378	xfs_da_brelse(tp, dbp);
1382	1379	error = xfs_da_read_buf(tp, dp,
1383	1380	xfs_dir2_db_to_da(mp, newdb),
1384	1381
1385	1382
1386	1383
1387	1384
1388	1385
1389	1386
...	...	@@ -1403,35 +1400,39 @@
1403	1400	if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
1404	1401	args->cmpresult = cmp;
1405	1402	*indexp = index;
1406		- /*
1407		- * case exact match: release the stored CI buffer if it
1408		- * exists and return the current buffer.
1409		- */
	1403	+ /* case exact match: return the current buffer. */
1410	1404	if (cmp == XFS_CMP_EXACT) {
1411		- if (cbp && cbp != dbp)
1412		- xfs_da_brelse(tp, cbp);
1413	1405	*dbpp = dbp;
1414	1406	return 0;
1415	1407	}
1416		- cbp = dbp;
	1408	+ cidb = curdb;
1417	1409	}
1418	1410	}
1419	1411	ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
1420	1412	/*
1421		- * Here, we can only be doing a lookup (not a rename or replace).
1422		- * If a case-insensitive match was found earlier, release the current
1423		- * buffer and return the stored CI matching buffer.
	1413	+ * Here, we can only be doing a lookup (not a rename or remove).
	1414	+ * If a case-insensitive match was found earlier, re-read the
	1415	+ * appropriate data block if required and return it.
1424	1416	*/
1425	1417	if (args->cmpresult == XFS_CMP_CASE) {
1426		- if (cbp != dbp)
	1418	+ ASSERT(cidb != -1);
	1419	+ if (cidb != curdb) {
1427	1420	xfs_da_brelse(tp, dbp);
1428		- *dbpp = cbp;
	1421	+ error = xfs_da_read_buf(tp, dp,
	1422	+ xfs_dir2_db_to_da(mp, cidb),
	1423	+ -1, &dbp, XFS_DATA_FORK);
	1424	+ if (error) {
	1425	+ xfs_da_brelse(tp, lbp);
	1426	+ return error;
	1427	+ }
	1428	+ }
	1429	+ *dbpp = dbp;
1429	1430	return 0;
1430	1431	}
1431	1432	/*
1432	1433	* No match found, return ENOENT.
1433	1434	*/
1434		- ASSERT(cbp == NULL);
	1435	+ ASSERT(cidb == -1);
1435	1436	if (dbp)
1436	1437	xfs_da_brelse(tp, dbp);
1437	1438	xfs_da_brelse(tp, lbp);