nilfs2: pass remount flag to parse_options
This adds is_remount argument to the parse_options() function that
obtains mount options from strings.
Previously, parse_options did not distinguish context whether it's
called for a new mount or remount, so the caller needed additional
verifications outside the function.
This allows parse_options to verify options and print messages
depending on the context.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 6a11243e..952f4cc 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -621,7 +621,7 @@
{Opt_err, NULL}
};
-static int parse_options(char *options, struct super_block *sb)
+static int parse_options(char *options, struct super_block *sb, int is_remount)
{
struct nilfs_sb_info *sbi = NILFS_SB(sb);
char *p;
@@ -666,8 +666,26 @@
case Opt_snapshot:
if (match_int(&args[0], &option) || option <= 0)
return 0;
- if (!(sb->s_flags & MS_RDONLY))
+ if (is_remount) {
+ if (!nilfs_test_opt(sbi, SNAPSHOT)) {
+ printk(KERN_ERR
+ "NILFS: cannot change regular "
+ "mount to snapshot.\n");
+ return 0;
+ } else if (option != sbi->s_snapshot_cno) {
+ printk(KERN_ERR
+ "NILFS: cannot remount to a "
+ "different snapshot.\n");
+ return 0;
+ }
+ break;
+ }
+ if (!(sb->s_flags & MS_RDONLY)) {
+ printk(KERN_ERR "NILFS: cannot mount snapshot "
+ "read/write. A read-only option is "
+ "required.\n");
return 0;
+ }
sbi->s_snapshot_cno = option;
nilfs_set_opt(sbi, SNAPSHOT);
break;
@@ -767,7 +785,7 @@
sbi->s_interval = le32_to_cpu(sbp->s_c_interval);
sbi->s_watermark = le32_to_cpu(sbp->s_c_block_max);
- return !parse_options(data, sb) ? -EINVAL : 0 ;
+ return !parse_options(data, sb, 0) ? -EINVAL : 0 ;
}
/**
@@ -929,32 +947,17 @@
old_opts.snapshot_cno = sbi->s_snapshot_cno;
was_snapshot = nilfs_test_opt(sbi, SNAPSHOT);
- if (!parse_options(data, sb)) {
+ if (!parse_options(data, sb, 1)) {
err = -EINVAL;
goto restore_opts;
}
sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
err = -EINVAL;
- if (was_snapshot) {
- if (!(*flags & MS_RDONLY)) {
- printk(KERN_ERR "NILFS (device %s): cannot remount "
- "snapshot read/write.\n",
- sb->s_id);
- goto restore_opts;
- } else if (sbi->s_snapshot_cno != old_opts.snapshot_cno) {
- printk(KERN_ERR "NILFS (device %s): cannot "
- "remount to a different snapshot.\n",
- sb->s_id);
- goto restore_opts;
- }
- } else {
- if (nilfs_test_opt(sbi, SNAPSHOT)) {
- printk(KERN_ERR "NILFS (device %s): cannot change "
- "a regular mount to a snapshot.\n",
- sb->s_id);
- goto restore_opts;
- }
+ if (was_snapshot && !(*flags & MS_RDONLY)) {
+ printk(KERN_ERR "NILFS (device %s): cannot remount snapshot "
+ "read/write.\n", sb->s_id);
+ goto restore_opts;
}
if (!nilfs_valid_fs(nilfs)) {