NTFS: Do more detailed reporting of why we cannot mount read-write by

     special casing the VOLUME_MODIFIED_BY_CHKDSK flag.

Signed-off-by: Anton Altaparmakov <aia21@cantab.net>

1 files changed, 27 insertions, 7 deletions

diff --git a/fs/ntfs/super.c b/fs/ntfs/super.c
index 489f7049146b..368a8ec10668 100644
--- a/fs/ntfs/super.c
+++ b/fs/ntfs/super.c
@@ -472,9 +472,16 @@ static int ntfs_remount(struct super_block *sb, int *flags, char *opt)
                         ntfs_error(sb, "Volume is dirty and read-only%s", es);
                         return -EROFS;
                 }
+                if (vol->vol_flags & VOLUME_MODIFIED_BY_CHKDSK) {
+                        ntfs_error(sb, "Volume has been modified by chkdsk "
+                                        "and is read-only%s", es);
+                        return -EROFS;
+                }
                 if (vol->vol_flags & VOLUME_MUST_MOUNT_RO_MASK) {
-                        ntfs_error(sb, "Volume has unsupported flags set and "
-                                        "is read-only%s", es);
+                        ntfs_error(sb, "Volume has unsupported flags set "
+                                        "(0x%x) and is read-only%s",
+                                        (unsigned)le16_to_cpu(vol->vol_flags),
+                                        es);
                         return -EROFS;
                 }
                 if (ntfs_set_volume_flags(vol, VOLUME_IS_DIRTY)) {
@@ -1845,11 +1852,24 @@ get_ctx_vol_failed:
         /* Make sure that no unsupported volume flags are set. */
         if (vol->vol_flags & VOLUME_MUST_MOUNT_RO_MASK) {
                 static const char *es1a = "Volume is dirty";
-                static const char *es1b = "Volume has unsupported flags set";
-                static const char *es2 = ".  Run chkdsk and mount in Windows.";
-                const char *es1;
-                
-                es1 = vol->vol_flags & VOLUME_IS_DIRTY ? es1a : es1b;
+                static const char *es1b = "Volume has been modified by chkdsk";
+                static const char *es1c = "Volume has unsupported flags set";
+                static const char *es2a = ".  Run chkdsk and mount in Windows.";
+                static const char *es2b = ".  Mount in Windows.";
+                const char *es1, *es2;
+
+                es2 = es2a;
+                if (vol->vol_flags & VOLUME_IS_DIRTY)
+                        es1 = es1a;
+                else if (vol->vol_flags & VOLUME_MODIFIED_BY_CHKDSK) {
+                        es1 = es1b;
+                        es2 = es2b;
+                } else {
+                        es1 = es1c;
+                        ntfs_warning(sb, "Unsupported volume flags 0x%x "
+                                        "encountered.",
+                                        (unsigned)le16_to_cpu(vol->vol_flags));
+                }
                 /* If a read-write mount, convert it to a read-only mount. */
                 if (!(sb->s_flags & MS_RDONLY)) {
                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |