ext4: trivial quota cleanup

The patch is aimed to reorganize and simplify quota code a bit.
Quota code is itself complex enough, but we can make it more readable
in some places:
- Move quota option parsing to separate functions.
- Simplify old-quota and journaled-quota mix check.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 7e8b1b4..79937e9 100644 (file)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1206,6 +1206,64 @@ static ext4_fsblk_t get_sb_block(void **data)
 
 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
 
+#ifdef CONFIG_QUOTA
+static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
+{
+       struct ext4_sb_info *sbi = EXT4_SB(sb);
+       char *qname;
+
+       if (sb_any_quota_loaded(sb) &&
+               !sbi->s_qf_names[qtype]) {
+               ext4_msg(sb, KERN_ERR,
+                       "Cannot change journaled "
+                       "quota options when quota turned on");
+               return 0;
+       }
+       qname = match_strdup(args);
+       if (!qname) {
+               ext4_msg(sb, KERN_ERR,
+                       "Not enough memory for storing quotafile name");
+               return 0;
+       }
+       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;
+       }
+       sbi->s_qf_names[qtype] = qname;
+       if (strchr(sbi->s_qf_names[qtype], '/')) {
+               ext4_msg(sb, KERN_ERR,
+                       "quotafile must be on filesystem root");
+               kfree(sbi->s_qf_names[qtype]);
+               sbi->s_qf_names[qtype] = NULL;
+               return 0;
+       }
+       set_opt(sbi->s_mount_opt, QUOTA);
+       return 1;
+}
+
+static int clear_qf_name(struct super_block *sb, int qtype)
+{
+
+       struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+       if (sb_any_quota_loaded(sb) &&
+               sbi->s_qf_names[qtype]) {
+               ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
+                       " when quota turned on");
+               return 0;
+       }
+       /*
+        * The space will be released later when all options are confirmed
+        * to be correct
+        */
+       sbi->s_qf_names[qtype] = NULL;
+       return 1;
+}
+#endif
+
 static int parse_options(char *options, struct super_block *sb,
                         unsigned long *journal_devnum,
                         unsigned int *journal_ioprio,
@@ -1217,8 +1275,7 @@ static int parse_options(char *options, struct super_block *sb,
        int data_opt = 0;
        int option;
 #ifdef CONFIG_QUOTA
-       int qtype, qfmt;
-       char *qname;
+       int qfmt;
 #endif
 
        if (!options)
@@ -1401,63 +1458,22 @@ static int parse_options(char *options, struct super_block *sb,
                        break;
 #ifdef CONFIG_QUOTA
                case Opt_usrjquota:
-                       qtype = USRQUOTA;
-                       goto set_qf_name;
-               case Opt_grpjquota:
-                       qtype = GRPQUOTA;
-set_qf_name:
-                       if (sb_any_quota_loaded(sb) &&
-                           !sbi->s_qf_names[qtype]) {
-                               ext4_msg(sb, KERN_ERR,
-                                      "Cannot change journaled "
-                                      "quota options when quota turned on");
+                       if (!set_qf_name(sb, USRQUOTA, &args[0]))
                                return 0;
-                       }
-                       qname = match_strdup(&args[0]);
-                       if (!qname) {
-                               ext4_msg(sb, KERN_ERR,
-                                       "Not enough memory for "
-                                       "storing quotafile name");
-                               return 0;
-                       }
-                       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;
-                       }
-                       sbi->s_qf_names[qtype] = qname;
-                       if (strchr(sbi->s_qf_names[qtype], '/')) {
-                               ext4_msg(sb, KERN_ERR,
-                                       "quotafile must be on "
-                                       "filesystem root");
-                               kfree(sbi->s_qf_names[qtype]);
-                               sbi->s_qf_names[qtype] = NULL;
+                       break;
+               case Opt_grpjquota:
+                       if (!set_qf_name(sb, GRPQUOTA, &args[0]))
                                return 0;
-                       }
-                       set_opt(sbi->s_mount_opt, QUOTA);
                        break;
                case Opt_offusrjquota:
-                       qtype = USRQUOTA;
-                       goto clear_qf_name;
+                       if (!clear_qf_name(sb, USRQUOTA))
+                               return 0;
+                       break;
                case Opt_offgrpjquota:
-                       qtype = GRPQUOTA;
-clear_qf_name:
-                       if (sb_any_quota_loaded(sb) &&
-                           sbi->s_qf_names[qtype]) {
-                               ext4_msg(sb, KERN_ERR, "Cannot change "
-                                       "journaled quota options when "
-                                       "quota turned on");
+                       if (!clear_qf_name(sb, GRPQUOTA))
                                return 0;
-                       }
-                       /*
-                        * The space will be released later when all options
-                        * are confirmed to be correct
-                        */
-                       sbi->s_qf_names[qtype] = NULL;
                        break;
+
                case Opt_jqfmt_vfsold:
                        qfmt = QFMT_VFS_OLD;
                        goto set_qf_format;
@@ -1630,8 +1646,7 @@ set_qf_format:
                if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
                        clear_opt(sbi->s_mount_opt, GRPQUOTA);
 
-               if ((sbi->s_qf_names[USRQUOTA] && test_opt(sb, GRPQUOTA)) ||
-                       (sbi->s_qf_names[GRPQUOTA] && test_opt(sb, USRQUOTA))) {
+               if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
                        ext4_msg(sb, KERN_ERR, "old and new quota "
                                        "format mixing");
                        return 0;