nilfs2: accept 64-bit checkpoint numbers in cp mount option

The current implementation doesn't mount snapshots with checkpoint
numbers larger than INT_MAX since it uses match_int() for parsing
"cp=" mount option.

This uses simple_strtoull() for the conversion to resolve the issue.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

1 files changed, 12 insertions, 13 deletions

diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index d92ebd5d60d9..a1cd444103ff 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -556,7 +556,6 @@ static int parse_options(char *options, struct super_block *sb, int is_remount)
         struct nilfs_sb_info *sbi = NILFS_SB(sb);
         char *p;
         substring_t args[MAX_OPT_ARGS];
-        int option;
 
         if (!options)
                 return 1;
@@ -594,8 +593,6 @@ static int parse_options(char *options, struct super_block *sb, int is_remount)
                         nilfs_write_opt(sbi, ERROR_MODE, ERRORS_CONT);
                         break;
                 case Opt_snapshot:
-                        if (match_int(&args[0], &option) || option <= 0)
-                                return 0;
                         if (is_remount) {
                                 printk(KERN_ERR
                                        "NILFS: \"%s\" option is invalid "
@@ -1065,7 +1062,7 @@ static int nilfs_identify(char *data, struct nilfs_super_data *sd)
 {
         char *p, *options = data;
         substring_t args[MAX_OPT_ARGS];
-        int option, token;
+        int token;
         int ret = 0;
 
         do {
@@ -1073,16 +1070,18 @@ static int nilfs_identify(char *data, struct nilfs_super_data *sd)
                 if (p != NULL && *p) {
                         token = match_token(p, tokens, args);
                         if (token == Opt_snapshot) {
-                                if (!(sd->flags & MS_RDONLY))
+                                if (!(sd->flags & MS_RDONLY)) {
                                         ret++;
-                                else {
-                                        ret = match_int(&args[0], &option);
-                                        if (!ret) {
-                                                if (option > 0)
-                                                        sd->cno = option;
-                                                else
-                                                        ret++;
-                                        }
+                                } else {
+                                        sd->cno = simple_strtoull(args[0].from,
+                                                                  NULL, 0);
+                                        /*
+                                         * No need to see the end pointer;
+                                         * match_token() has done syntax
+                                         * checking.
+                                         */
+                                        if (sd->cno == 0)
+                                                ret++;
                                 }
                         }
                         if (ret)