ext4-quota-cleanup

   1 ext4: trivial quota cleanup
   2
   3 The patch is aimed to reorganize and simplify quota src code.
   4 Quota code is itself complex enouth, but we can make it more readable
   5 in some places:
   6 - Move quota option parsing to separate functions.
   7 - Simplify old-quota and journaled-quota mix check.
   8 diff --git a/fs/ext4/super.c b/fs/ext4/super.c
   9 index 6459bb7..7c4b742 100644
  10 --- a/fs/ext4/super.c
  11 +++ b/fs/ext4/super.c
  12 @@ -1172,6 +1172,63 @@ static ext4_fsblk_t get_sb_block(void **data)
  13
  14  #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
  15
  16 +#ifdef CONFIG_QUOTA
  17 +static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
  18 +{
  19 +       struct ext4_sb_info *sbi = EXT4_SB(sb);
  20 +       char *qname;
  21 +
  22 +       if (sb_any_quota_loaded(sb) &&
  23 +               !sbi->s_qf_names[qtype]) {
  24 +               ext4_msg(sb, KERN_ERR,
  25 +                       "Cannot change journaled "
  26 +                       "quota options when quota turned on");
  27 +               return 0;
  28 +       }
  29 +       qname = match_strdup(args);
  30 +       if (!qname) {
  31 +               ext4_msg(sb, KERN_ERR,
  32 +                       "Not enough memory for storing quotafile name");
  33 +               return 0;
  34 +       }
  35 +       if (sbi->s_qf_names[qtype] &&
  36 +               strcmp(sbi->s_qf_names[qtype], qname)) {
  37 +               ext4_msg(sb, KERN_ERR,
  38 +                       "%s quota file already specified", QTYPE2NAME(qtype));
  39 +               kfree(qname);
  40 +               return 0;
  41 +       }
  42 +       sbi->s_qf_names[qtype] = qname;
  43 +       if (strchr(sbi->s_qf_names[qtype], '/')) {
  44 +               ext4_msg(sb, KERN_ERR,
  45 +                       "quotafile must be on filesystem root");
  46 +               kfree(sbi->s_qf_names[qtype]);
  47 +               sbi->s_qf_names[qtype] = NULL;
  48 +               return 0;
  49 +       }
  50 +       set_opt(sbi->s_mount_opt, QUOTA);
  51 +       return 1;
  52 +}
  53 +
  54 +static int clear_qf_name(struct super_block *sb, int qtype) {
  55 +
  56 +       struct ext4_sb_info *sbi = EXT4_SB(sb);
  57 +
  58 +       if (sb_any_quota_loaded(sb) &&
  59 +               sbi->s_qf_names[qtype]) {
  60 +               ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
  61 +                       " when quota turned on");
  62 +               return 0;
  63 +       }
  64 +       /*
  65 +        * The space will be released later when all options are confirmed
  66 +        * to be correct
  67 +        */
  68 +       sbi->s_qf_names[qtype] = NULL;
  69 +       return 1;
  70 +}
  71 +#endif
  72 +
  73  static int parse_options(char *options, struct super_block *sb,
  74                          unsigned long *journal_devnum,
  75                          unsigned int *journal_ioprio,
  76 @@ -1183,8 +1240,7 @@ static int parse_options(char *options, struct super_block *sb,
  77         int data_opt = 0;
  78         int option;
  79  #ifdef CONFIG_QUOTA
  80 -       int qtype, qfmt;
  81 -       char *qname;
  82 +       int qfmt;
  83  #endif
  84
  85         if (!options)
  86 @@ -1360,63 +1416,22 @@ static int parse_options(char *options, struct super_block *sb,
  87                         break;
  88  #ifdef CONFIG_QUOTA
  89                 case Opt_usrjquota:
  90 -                       qtype = USRQUOTA;
  91 -                       goto set_qf_name;
  92 -               case Opt_grpjquota:
  93 -                       qtype = GRPQUOTA;
  94 -set_qf_name:
  95 -                       if (sb_any_quota_loaded(sb) &&
  96 -                           !sbi->s_qf_names[qtype]) {
  97 -                               ext4_msg(sb, KERN_ERR,
  98 -                                      "Cannot change journaled "
  99 -                                      "quota options when quota turned on");
 100 -                               return 0;
 101 -                       }
 102 -                       qname = match_strdup(&args[0]);
 103 -                       if (!qname) {
 104 -                               ext4_msg(sb, KERN_ERR,
 105 -                                       "Not enough memory for "
 106 -                                       "storing quotafile name");
 107 +                       if (!set_qf_name(sb, USRQUOTA, &args[0]))
 108                                 return 0;
 109 -                       }
 110 -                       if (sbi->s_qf_names[qtype] &&
 111 -                           strcmp(sbi->s_qf_names[qtype], qname)) {
 112 -                               ext4_msg(sb, KERN_ERR,
 113 -                                       "%s quota file already "
 114 -                                       "specified", QTYPE2NAME(qtype));
 115 -                               kfree(qname);
 116 -                               return 0;
 117 -                       }
 118 -                       sbi->s_qf_names[qtype] = qname;
 119 -                       if (strchr(sbi->s_qf_names[qtype], '/')) {
 120 -                               ext4_msg(sb, KERN_ERR,
 121 -                                       "quotafile must be on "
 122 -                                       "filesystem root");
 123 -                               kfree(sbi->s_qf_names[qtype]);
 124 -                               sbi->s_qf_names[qtype] = NULL;
 125 +                       break;
 126 +               case Opt_grpjquota:
 127 +                       if (!set_qf_name(sb, GRPQUOTA, &args[0]))
 128                                 return 0;
 129 -                       }
 130 -                       set_opt(sbi->s_mount_opt, QUOTA);
 131                         break;
 132                 case Opt_offusrjquota:
 133 -                       qtype = USRQUOTA;
 134 -                       goto clear_qf_name;
 135 +                       if (!clear_qf_name(sb, USRQUOTA))
 136 +                               return 0;
 137 +                       break;
 138                 case Opt_offgrpjquota:
 139 -                       qtype = GRPQUOTA;
 140 -clear_qf_name:
 141 -                       if (sb_any_quota_loaded(sb) &&
 142 -                           sbi->s_qf_names[qtype]) {
 143 -                               ext4_msg(sb, KERN_ERR, "Cannot change "
 144 -                                       "journaled quota options when "
 145 -                                       "quota turned on");
 146 +                       if (!clear_qf_name(sb, GRPQUOTA))
 147                                 return 0;
 148 -                       }
 149 -                       /*
 150 -                        * The space will be released later when all options
 151 -                        * are confirmed to be correct
 152 -                        */
 153 -                       sbi->s_qf_names[qtype] = NULL;
 154                         break;
 155 +
 156                 case Opt_jqfmt_vfsold:
 157                         qfmt = QFMT_VFS_OLD;
 158                         goto set_qf_format;
 159 @@ -1577,8 +1592,8 @@ set_qf_format:
 160                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
 161                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
 162
 163 -               if ((sbi->s_qf_names[USRQUOTA] && test_opt(sb, GRPQUOTA)) ||
 164 -                   (sbi->s_qf_names[GRPQUOTA] && test_opt(sb, USRQUOTA))) {
 165 +               if (sbi->s_mount_opt & (EXT4_MOUNT_USRQUOTA |
 166 +                                               EXT4_MOUNT_GRPQUOTA)) {
 167                         ext4_msg(sb, KERN_ERR, "old and new quota "
 168                                         "format mixing");
 169                         return 0;