Before this commit, all exfat-defined mount options could not be
modified dynamically via remount, and no error was returned.
After this commit, these three exfat-defined mount options
(discard, zero_size_dir, and errors) can be modified dynamically
via remount. While other exfat-defined mount options cannot be
modified dynamically via remount because their old settings are
cached in inodes or dentries, modifying them will be rejected with
an error.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@xxxxxxxx>
---
fs/exfat/super.c | 44 ++++++++++++++++++++++++++++++++++++++------
1 file changed, 38 insertions(+), 6 deletions(-)
diff --git a/fs/exfat/super.c b/fs/exfat/super.c
index 7ed858937d45..9e2e8c1e9609 100644
--- a/fs/exfat/super.c
+++ b/fs/exfat/super.c
@@ -243,11 +243,11 @@ static const struct fs_parameter_spec exfat_parameters[] = {
fsparam_u32oct("allow_utime", Opt_allow_utime),
fsparam_string("iocharset", Opt_charset),
fsparam_enum("errors", Opt_errors, exfat_param_enums),
- fsparam_flag("discard", Opt_discard),
+ fsparam_flag_no("discard", Opt_discard),
fsparam_flag("keep_last_dots", Opt_keep_last_dots),
fsparam_flag("sys_tz", Opt_sys_tz),
fsparam_s32("time_offset", Opt_time_offset),
- fsparam_flag("zero_size_dir", Opt_zero_size_dir),
+ fsparam_flag_no("zero_size_dir", Opt_zero_size_dir),
__fsparam(NULL, "utf8", Opt_utf8, fs_param_deprecated,
NULL),
__fsparam(NULL, "debug", Opt_debug, fs_param_deprecated,
@@ -299,7 +299,7 @@ static int exfat_parse_param(struct fs_context *fc, struct fs_parameter *param)
opts->errors = result.uint_32;
break;
case Opt_discard:
- opts->discard = 1;
+ opts->discard = !result.negated;
break;
case Opt_keep_last_dots:
opts->keep_last_dots = 1;
@@ -317,7 +317,7 @@ static int exfat_parse_param(struct fs_context *fc, struct fs_parameter *param)
opts->time_offset = result.int_32;
break;
case Opt_zero_size_dir:
- opts->zero_size_dir = true;
+ opts->zero_size_dir = !result.negated;
break;
case Opt_utf8:
case Opt_debug:
@@ -732,12 +732,44 @@ static void exfat_free(struct fs_context *fc)
static int exfat_reconfigure(struct fs_context *fc)
{
struct super_block *sb = fc->root->d_sb;
+ struct exfat_sb_info *remount_sbi = fc->s_fs_info;
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+ struct exfat_mount_options *new_opts = &remount_sbi->options;
+ struct exfat_mount_options *cur_opts = &sbi->options;
+
fc->sb_flags |= SB_NODIRATIME;
sync_filesystem(sb);
- mutex_lock(&EXFAT_SB(sb)->s_lock);
+ mutex_lock(&sbi->s_lock);
exfat_clear_volume_dirty(sb);
- mutex_unlock(&EXFAT_SB(sb)->s_lock);
+ mutex_unlock(&sbi->s_lock);
+
+ if (new_opts->allow_utime == (unsigned short)-1)
+ new_opts->allow_utime = ~new_opts->fs_dmask & 0022;
+
+ /*
+ * Since the old settings of these mount options are cached in
+ * inodes or dentries, they cannot be modified dynamically.
+ */
+ if (strcmp(new_opts->iocharset, cur_opts->iocharset) ||
+ new_opts->keep_last_dots != cur_opts->keep_last_dots ||
+ new_opts->sys_tz != cur_opts->sys_tz ||
+ new_opts->time_offset != cur_opts->time_offset ||
+ !uid_eq(new_opts->fs_uid, cur_opts->fs_uid) ||
+ !gid_eq(new_opts->fs_gid, cur_opts->fs_gid) ||
+ new_opts->fs_fmask != cur_opts->fs_fmask ||
+ new_opts->fs_dmask != cur_opts->fs_dmask ||
+ new_opts->allow_utime != cur_opts->allow_utime)
+ return -EINVAL;
+
+ if (new_opts->discard != cur_opts->discard &&
+ new_opts->discard &&
+ !bdev_max_discard_sectors(sb->s_bdev)) {
+ exfat_warn(sb, "remounting with \"discard\" option, but the device does not support discard");
+ return -EINVAL;
+ }
+
+ swap(*cur_opts, *new_opts);
return 0;
}
--
2.43.0
