Re: [PATCH 0/4] ext4: Fix regression in mount option parsing and a small cleanup

[Ted Ts'o <tytso@mit.edu>]

On Mon, Apr 16, 2012 at 02:25:30PM +0200, Jan Kara wrote:
> 
> 
>   this patch series aims at fixing a regression in parsing of
> journalled quota mount options introduced by Ted's mount option
> parsing rewrite. Patches 1 and 2 cleanup the code a bit and patch 3
> then fixes the regression. Patch 4 is a tiny cleanup.

Hi Jan,

Apologies for breaking the journalled mount options, and thank you for
this patch series.  I agree it's an improvement on what we currently
have.  My main concern with though, is I'd like to fix this for 3.4,
and the four patches together is a bit larger than what I feel
comfortable pushing to Linus at this point.  What do you think of this
patch now, and I'll we'll add your changes for the next merge window?

      	       	    	      	   	   - Ted

>From 816c710aa92cdf442e6fc722b74bb99bf8575a30 Mon Sep 17 00:00:00 2001
From: Theodore Ts'o <tytso@mit.edu>
Date: Mon, 16 Apr 2012 12:54:07 -0400
Subject: [PATCH] ext4: fix handling of journalled quota options

Commit 26092bf5 broke handling of journalled quota mount options by
trying to parse argument of every mount option as a number.  Fix this
by dealing with the quota options before we call match_int().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
---
 fs/ext4/super.c |   32 +++++++++++++++-----------------
 1 file changed, 15 insertions(+), 17 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index ef7db50..6da1935 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1305,20 +1305,20 @@ static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
 		ext4_msg(sb, KERN_ERR,
 			"Cannot change journaled "
 			"quota options when quota turned on");
-		return 0;
+		return -1;
 	}
 	qname = match_strdup(args);
 	if (!qname) {
 		ext4_msg(sb, KERN_ERR,
 			"Not enough memory for storing quotafile name");
-		return 0;
+		return -1;
 	}
 	if (sbi->s_qf_names[qtype] &&
 		strcmp(sbi->s_qf_names[qtype], qname)) {
 		ext4_msg(sb, KERN_ERR,
 			"%s quota file already specified", QTYPE2NAME(qtype));
 		kfree(qname);
-		return 0;
+		return -1;
 	}
 	sbi->s_qf_names[qtype] = qname;
 	if (strchr(sbi->s_qf_names[qtype], '/')) {
@@ -1326,7 +1326,7 @@ static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
 			"quotafile must be on filesystem root");
 		kfree(sbi->s_qf_names[qtype]);
 		sbi->s_qf_names[qtype] = NULL;
-		return 0;
+		return -1;
 	}
 	set_opt(sb, QUOTA);
 	return 1;
@@ -1341,7 +1341,7 @@ static int clear_qf_name(struct super_block *sb, int qtype)
 		sbi->s_qf_names[qtype]) {
 		ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
 			" when quota turned on");
-		return 0;
+		return -1;
 	}
 	/*
 	 * The space will be released later when all options are confirmed
@@ -1450,6 +1450,16 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token,
 	const struct mount_opts *m;
 	int arg = 0;
 
+#ifdef CONFIG_QUOTA
+	if (token == Opt_usrjquota)
+		return set_qf_name(sb, USRQUOTA, &args[0]);
+	else if (token == Opt_grpjquota)
+		return set_qf_name(sb, GRPQUOTA, &args[0]);
+	else if (token == Opt_offusrjquota)
+		return clear_qf_name(sb, USRQUOTA);
+	else if (token == Opt_offgrpjquota)
+		return clear_qf_name(sb, GRPQUOTA);
+#endif
 	if (args->from && match_int(args, &arg))
 		return -1;
 	switch (token) {
@@ -1549,18 +1559,6 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token,
 				sbi->s_mount_opt |= m->mount_opt;
 			}
 #ifdef CONFIG_QUOTA
-		} else if (token == Opt_usrjquota) {
-			if (!set_qf_name(sb, USRQUOTA, &args[0]))
-				return -1;
-		} else if (token == Opt_grpjquota) {
-			if (!set_qf_name(sb, GRPQUOTA, &args[0]))
-				return -1;
-		} else if (token == Opt_offusrjquota) {
-			if (!clear_qf_name(sb, USRQUOTA))
-				return -1;
-		} else if (token == Opt_offgrpjquota) {
-			if (!clear_qf_name(sb, GRPQUOTA))
-				return -1;
 		} else if (m->flags & MOPT_QFMT) {
 			if (sb_any_quota_loaded(sb) &&
 			    sbi->s_jquota_fmt != m->mount_opt) {
-- 
1.7.10.rc3