JFFS2: Add parameter to reserve disk space for root

[deliverable/linux.git] / fs / jffs2 / super.c

diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
index f9916f312bd81e3590fde1c92a025458cb64ab11..66d44560f75dd7d72d87c6ad00bbe6c5e5bc9657 100644 (file)
--- a/fs/jffs2/super.c
+++ b/fs/jffs2/super.c
@@ -105,6 +105,8 @@ static int jffs2_show_options(struct seq_file *s, struct dentry *root)
 
        if (opts->override_compr)
                seq_printf(s, ",compr=%s", jffs2_compr_name(opts->compr));
+       if (opts->rp_size)
+               seq_printf(s, ",rp_size=%u", opts->rp_size / 1024);
 
        return 0;
 }
@@ -171,15 +173,18 @@ static const struct export_operations jffs2_export_ops = {
  * JFFS2 mount options.
  *
  * Opt_override_compr: override default compressor
+ * Opt_rp_size: size of reserved pool in KiB
  * Opt_err: just end of array marker
  */
 enum {
        Opt_override_compr,
+       Opt_rp_size,
        Opt_err,
 };
 
 static const match_table_t tokens = {
        {Opt_override_compr, "compr=%s"},
+       {Opt_rp_size, "rp_size=%u"},
        {Opt_err, NULL},
 };
 
@@ -187,6 +192,7 @@ static int jffs2_parse_options(struct jffs2_sb_info *c, char *data)
 {
        substring_t args[MAX_OPT_ARGS];
        char *p, *name;
+       unsigned int opt;
 
        if (!data)
                return 0;
@@ -224,6 +230,17 @@ static int jffs2_parse_options(struct jffs2_sb_info *c, char *data)
                        kfree(name);
                        c->mount_opts.override_compr = true;
                        break;
+               case Opt_rp_size:
+                       if (match_int(&args[0], &opt))
+                               return -EINVAL;
+                       opt *= 1024;
+                       if (opt > c->mtd->size) {
+                               pr_warn("Too large reserve pool specified, max "
+                                       "is %llu KB\n", c->mtd->size / 1024);
+                               return -EINVAL;
+                       }
+                       c->mount_opts.rp_size = opt;
+                       break;
                default:
                        pr_err("Error: unrecognized mount option '%s' or missing value\n",
                               p);