[ 3.5.y.z extended stable ] Patch "ext4: check dioread_nolock on remount" has been added to staging queue

[Herton Ronaldo Krzesinski]

This is a note to let you know that I have just added a patch titled

    ext4: check dioread_nolock on remount

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Herton

------

>From fea6f34f2fca0526716fa0ac4f326edcf493ce0f Mon Sep 17 00:00:00 2001
From: Jan Kara <jack at suse.cz>
Date: Thu, 20 Dec 2012 00:07:18 -0500
Subject: [PATCH] ext4: check dioread_nolock on remount

commit 261cb20cb2f0737a247aaf08dff7eb065e3e5b66 upstream.

Currently we allow enabling dioread_nolock mount option on remount for
filesystems where blocksize < PAGE_CACHE_SIZE.  This isn't really
supported so fix the bug by moving the check for blocksize !=
PAGE_CACHE_SIZE into parse_options(). Change the original PAGE_SIZE to
PAGE_CACHE_SIZE along the way because that's what we are really
interested in.

Signed-off-by: Jan Kara <jack at suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso at mit.edu>
Reviewed-by: Eric Sandeen <sandeen at redhat.com>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
---
 fs/ext4/super.c |   22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 993392b..b045207 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1656,9 +1656,7 @@ static int parse_options(char *options, struct super_block *sb,
 			 unsigned int *journal_ioprio,
 			 int is_remount)
 {
-#ifdef CONFIG_QUOTA
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
-#endif
 	char *p;
 	substring_t args[MAX_OPT_ARGS];
 	int token;
@@ -1707,6 +1705,16 @@ static int parse_options(char *options, struct super_block *sb,
 		}
 	}
 #endif
+	if (test_opt(sb, DIOREAD_NOLOCK)) {
+		int blocksize =
+			BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
+
+		if (blocksize < PAGE_CACHE_SIZE) {
+			ext4_msg(sb, KERN_ERR, "can't mount with "
+				 "dioread_nolock if block size != PAGE_SIZE");
+			return 0;
+		}
+	}
 	return 1;
 }

@@ -3410,15 +3418,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 			clear_opt(sb, DELALLOC);
 	}

-	blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
-	if (test_opt(sb, DIOREAD_NOLOCK)) {
-		if (blocksize < PAGE_SIZE) {
-			ext4_msg(sb, KERN_ERR, "can't mount with "
-				 "dioread_nolock if block size != PAGE_SIZE");
-			goto failed_mount;
-		}
-	}
-
 	sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 		(test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);

@@ -3460,6 +3459,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 	if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
 		goto failed_mount;

+	blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
 	if (blocksize < EXT4_MIN_BLOCK_SIZE ||
 	    blocksize > EXT4_MAX_BLOCK_SIZE) {
 		ext4_msg(sb, KERN_ERR,
--
1.7.9.5