ext4: check ext2/3 compatibility outside handle_mount_opt()

At the parsing phase of mount in the new mount api sb will not be
available so move ext2/3 compatibility check outside handle_mount_opt().
Unfortunately we will lose the ability to show exactly which option is
not compatible.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Link: https://lore.kernel.org/r/20211027141857.33657-8-lczerner@redhat.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index c082aea..6839563 100644 (file)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -89,8 +89,8 @@ static void ext4_clear_request_list(void);
 static struct inode *ext4_get_journal_inode(struct super_block *sb,
                                            unsigned int journal_inum);
 static int ext4_validate_options(struct fs_context *fc);
-static int ext4_check_quota_consistency(struct fs_context *fc,
-                                       struct super_block *sb);
+static int ext4_check_opt_consistency(struct fs_context *fc,
+                                     struct super_block *sb);
 static void ext4_apply_quota_options(struct fs_context *fc,
                                     struct super_block *sb);
 
@@ -2199,6 +2199,7 @@ struct ext4_fs_context {
        unsigned long   journal_devnum;
        unsigned int    journal_ioprio;
        int             mb_optimize_scan;
+       unsigned int    opt_flags;      /* MOPT flags */
 };
 
 #ifdef CONFIG_QUOTA
@@ -2329,25 +2330,14 @@ static int handle_mount_opt(struct fs_context *fc, struct fs_parameter *param)
                if (token == m->token)
                        break;
 
+       ctx->opt_flags |= m->flags;
+
        if (m->token == Opt_err) {
                ext4_msg(NULL, KERN_ERR, "Unrecognized mount option \"%s\" "
                         "or missing value", param->key);
                return -EINVAL;
        }
 
-       if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
-               ext4_msg(NULL, KERN_ERR,
-                        "Mount option \"%s\" incompatible with ext2",
-                        param->key);
-               return -EINVAL;
-       }
-       if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
-               ext4_msg(NULL, KERN_ERR,
-                        "Mount option \"%s\" incompatible with ext3",
-                        param->key);
-               return -EINVAL;
-       }
-
        if (m->flags & MOPT_EXPLICIT) {
                if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
                        set_opt2(sb, EXPLICIT_DELALLOC);
@@ -2630,7 +2620,7 @@ static int parse_options(char *options, struct super_block *sb,
        if (ret < 0)
                return 0;
 
-       ret = ext4_check_quota_consistency(&fc, sb);
+       ret = ext4_check_opt_consistency(&fc, sb);
        if (ret < 0)
                return 0;
 
@@ -2724,6 +2714,25 @@ err_feature:
 #endif
 }
 
+static int ext4_check_opt_consistency(struct fs_context *fc,
+                                     struct super_block *sb)
+{
+       struct ext4_fs_context *ctx = fc->fs_private;
+
+       if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
+               ext4_msg(NULL, KERN_ERR,
+                        "Mount option(s) incompatible with ext2");
+               return -EINVAL;
+       }
+       if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
+               ext4_msg(NULL, KERN_ERR,
+                        "Mount option(s) incompatible with ext3");
+               return -EINVAL;
+       }
+
+       return ext4_check_quota_consistency(fc, sb);
+}
+
 static int ext4_validate_options(struct fs_context *fc)
 {
        struct ext4_sb_info *sbi = fc->s_fs_info;