fs/hfsplus/options.c

   1 /*
   2  *  linux/fs/hfsplus/options.c
   3  *
   4  * Copyright (C) 2001
   5  * Brad Boyer (flar@allandria.com)
   6  * (C) 2003 Ardis Technologies <roman@ardistech.com>
   7  *
   8  * Option parsing
   9  */
  10
  11 #include <linux/string.h>
  12 #include <linux/kernel.h>
  13 #include <linux/sched.h>
  14 #include <linux/parser.h>
  15 #include <linux/nls.h>
  16 #include <linux/mount.h>
  17 #include <linux/seq_file.h>
  18 #include <linux/slab.h>
  19 #include "hfsplus_fs.h"
  20
  21 enum {
  22         opt_creator, opt_type,
  23         opt_umask, opt_uid, opt_gid,
  24         opt_part, opt_session, opt_nls,
  25         opt_nodecompose, opt_decompose,
  26         opt_barrier, opt_nobarrier,
  27         opt_force, opt_err
  28 };
  29
  30 static const match_table_t tokens = {
  31         { opt_creator, "creator=%s" },
  32         { opt_type, "type=%s" },
  33         { opt_umask, "umask=%o" },
  34         { opt_uid, "uid=%u" },
  35         { opt_gid, "gid=%u" },
  36         { opt_part, "part=%u" },
  37         { opt_session, "session=%u" },
  38         { opt_nls, "nls=%s" },
  39         { opt_decompose, "decompose" },
  40         { opt_nodecompose, "nodecompose" },
  41         { opt_barrier, "barrier" },
  42         { opt_nobarrier, "nobarrier" },
  43         { opt_force, "force" },
  44         { opt_err, NULL }
  45 };
  46
  47 /* Initialize an options object to reasonable defaults */
  48 void hfsplus_fill_defaults(struct hfsplus_sb_info *opts)
  49 {
  50         if (!opts)
  51                 return;
  52
  53         opts->creator = HFSPLUS_DEF_CR_TYPE;
  54         opts->type = HFSPLUS_DEF_CR_TYPE;
  55         opts->umask = current_umask();
  56         opts->uid = current_uid();
  57         opts->gid = current_gid();
  58         opts->part = -1;
  59         opts->session = -1;
  60 }
  61
  62 /* convert a "four byte character" to a 32 bit int with error checks */
  63 static inline int match_fourchar(substring_t *arg, u32 *result)
  64 {
  65         if (arg->to - arg->from != 4)
  66                 return -EINVAL;
  67         memcpy(result, arg->from, 4);
  68         return 0;
  69 }
  70
  71 int hfsplus_parse_options_remount(char *input, int *force)
  72 {
  73         char *p;
  74         substring_t args[MAX_OPT_ARGS];
  75         int token;
  76
  77         if (!input)
  78                 return 0;
  79
  80         while ((p = strsep(&input, ",")) != NULL) {
  81                 if (!*p)
  82                         continue;
  83
  84                 token = match_token(p, tokens, args);
  85                 switch (token) {
  86                 case opt_force:
  87                         *force = 1;
  88                         break;
  89                 default:
  90                         break;
  91                 }
  92         }
  93
  94         return 1;
  95 }
  96
  97 /* Parse options from mount. Returns 0 on failure */
  98 /* input is the options passed to mount() as a string */
  99 int hfsplus_parse_options(char *input, struct hfsplus_sb_info *sbi)
 100 {
 101         char *p;
 102         substring_t args[MAX_OPT_ARGS];
 103         int tmp, token;
 104
 105         if (!input)
 106                 goto done;
 107
 108         while ((p = strsep(&input, ",")) != NULL) {
 109                 if (!*p)
 110                         continue;
 111
 112                 token = match_token(p, tokens, args);
 113                 switch (token) {
 114                 case opt_creator:
 115                         if (match_fourchar(&args[0], &sbi->creator)) {
 116                                 printk(KERN_ERR "hfs: creator requires a 4 character value\n");
 117                                 return 0;
 118                         }
 119                         break;
 120                 case opt_type:
 121                         if (match_fourchar(&args[0], &sbi->type)) {
 122                                 printk(KERN_ERR "hfs: type requires a 4 character value\n");
 123                                 return 0;
 124                         }
 125                         break;
 126                 case opt_umask:
 127                         if (match_octal(&args[0], &tmp)) {
 128                                 printk(KERN_ERR "hfs: umask requires a value\n");
 129                                 return 0;
 130                         }
 131                         sbi->umask = (umode_t)tmp;
 132                         break;
 133                 case opt_uid:
 134                         if (match_int(&args[0], &tmp)) {
 135                                 printk(KERN_ERR "hfs: uid requires an argument\n");
 136                                 return 0;
 137                         }
 138                         sbi->uid = (uid_t)tmp;
 139                         break;
 140                 case opt_gid:
 141                         if (match_int(&args[0], &tmp)) {
 142                                 printk(KERN_ERR "hfs: gid requires an argument\n");
 143                                 return 0;
 144                         }
 145                         sbi->gid = (gid_t)tmp;
 146                         break;
 147                 case opt_part:
 148                         if (match_int(&args[0], &sbi->part)) {
 149                                 printk(KERN_ERR "hfs: part requires an argument\n");
 150                                 return 0;
 151                         }
 152                         break;
 153                 case opt_session:
 154                         if (match_int(&args[0], &sbi->session)) {
 155                                 printk(KERN_ERR "hfs: session requires an argument\n");
 156                                 return 0;
 157                         }
 158                         break;
 159                 case opt_nls:
 160                         if (sbi->nls) {
 161                                 printk(KERN_ERR "hfs: unable to change nls mapping\n");
 162                                 return 0;
 163                         }
 164                         p = match_strdup(&args[0]);
 165                         if (p)
 166                                 sbi->nls = load_nls(p);
 167                         if (!sbi->nls) {
 168                                 printk(KERN_ERR "hfs: unable to load "
 169                                                 "nls mapping \"%s\"\n",
 170                                         p);
 171                                 kfree(p);
 172                                 return 0;
 173                         }
 174                         kfree(p);
 175                         break;
 176                 case opt_decompose:
 177                         clear_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags);
 178                         break;
 179                 case opt_nodecompose:
 180                         set_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags);
 181                         break;
 182                 case opt_barrier:
 183                         clear_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags);
 184                         break;
 185                 case opt_nobarrier:
 186                         set_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags);
 187                         break;
 188                 case opt_force:
 189                         set_bit(HFSPLUS_SB_FORCE, &sbi->flags);
 190                         break;
 191                 default:
 192                         return 0;
 193                 }
 194         }
 195
 196 done:
 197         if (!sbi->nls) {
 198                 /* try utf8 first, as this is the old default behaviour */
 199                 sbi->nls = load_nls("utf8");
 200                 if (!sbi->nls)
 201                         sbi->nls = load_nls_default();
 202                 if (!sbi->nls)
 203                         return 0;
 204         }
 205
 206         return 1;
 207 }
 208
 209 int hfsplus_show_options(struct seq_file *seq, struct vfsmount *mnt)
 210 {
 211         struct hfsplus_sb_info *sbi = HFSPLUS_SB(mnt->mnt_sb);
 212
 213         if (sbi->creator != HFSPLUS_DEF_CR_TYPE)
 214                 seq_printf(seq, ",creator=%.4s", (char *)&sbi->creator);
 215         if (sbi->type != HFSPLUS_DEF_CR_TYPE)
 216                 seq_printf(seq, ",type=%.4s", (char *)&sbi->type);
 217         seq_printf(seq, ",umask=%o,uid=%u,gid=%u", sbi->umask,
 218                 sbi->uid, sbi->gid);
 219         if (sbi->part >= 0)
 220                 seq_printf(seq, ",part=%u", sbi->part);
 221         if (sbi->session >= 0)
 222                 seq_printf(seq, ",session=%u", sbi->session);
 223         if (sbi->nls)
 224                 seq_printf(seq, ",nls=%s", sbi->nls->charset);
 225         if (test_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags))
 226                 seq_printf(seq, ",nodecompose");
 227         if (test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags))
 228                 seq_printf(seq, ",nobarrier");
 229         return 0;
 230 }