[PATCH] lockdep: annotate NTFS locking rules
NTFS uses lots of type-opaque objects which acquire their true identity
runtime - so the lock validator needs to be helped in a couple of places to
figure out object types.
Many thanks to Anton Altaparmakov for giving lots of explanations about NTFS
locking rules.
Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/ntfs/super.c b/fs/ntfs/super.c
index 0e14ace..74e0ee8 100644
--- a/fs/ntfs/super.c
+++ b/fs/ntfs/super.c
@@ -1724,6 +1724,14 @@
return FALSE;
}
+/*
+ * The lcn and mft bitmap inodes are NTFS-internal inodes with
+ * their own special locking rules:
+ */
+static struct lock_class_key
+ lcnbmp_runlist_lock_key, lcnbmp_mrec_lock_key,
+ mftbmp_runlist_lock_key, mftbmp_mrec_lock_key;
+
/**
* load_system_files - open the system files using normal functions
* @vol: ntfs super block describing device whose system files to load
@@ -1780,6 +1788,10 @@
ntfs_error(sb, "Failed to load $MFT/$BITMAP attribute.");
goto iput_mirr_err_out;
}
+ lockdep_set_class(&NTFS_I(vol->mftbmp_ino)->runlist.lock,
+ &mftbmp_runlist_lock_key);
+ lockdep_set_class(&NTFS_I(vol->mftbmp_ino)->mrec_lock,
+ &mftbmp_mrec_lock_key);
/* Read upcase table and setup @vol->upcase and @vol->upcase_len. */
if (!load_and_init_upcase(vol))
goto iput_mftbmp_err_out;
@@ -1802,6 +1814,11 @@
iput(vol->lcnbmp_ino);
goto bitmap_failed;
}
+ lockdep_set_class(&NTFS_I(vol->lcnbmp_ino)->runlist.lock,
+ &lcnbmp_runlist_lock_key);
+ lockdep_set_class(&NTFS_I(vol->lcnbmp_ino)->mrec_lock,
+ &lcnbmp_mrec_lock_key);
+
NInoSetSparseDisabled(NTFS_I(vol->lcnbmp_ino));
if ((vol->nr_clusters + 7) >> 3 > i_size_read(vol->lcnbmp_ino)) {
iput(vol->lcnbmp_ino);
@@ -2743,6 +2760,17 @@
struct inode *tmp_ino;
int blocksize, result;
+ /*
+ * We do a pretty difficult piece of bootstrap by reading the
+ * MFT (and other metadata) from disk into memory. We'll only
+ * release this metadata during umount, so the locking patterns
+ * observed during bootstrap do not count. So turn off the
+ * observation of locking patterns (strictly for this context
+ * only) while mounting NTFS. [The validator is still active
+ * otherwise, even for this context: it will for example record
+ * lock class registrations.]
+ */
+ lockdep_off();
ntfs_debug("Entering.");
#ifndef NTFS_RW
sb->s_flags |= MS_RDONLY;
@@ -2754,6 +2782,7 @@
if (!silent)
ntfs_error(sb, "Allocation of NTFS volume structure "
"failed. Aborting mount...");
+ lockdep_on();
return -ENOMEM;
}
/* Initialize ntfs_volume structure. */
@@ -2940,6 +2969,7 @@
mutex_unlock(&ntfs_lock);
sb->s_export_op = &ntfs_export_ops;
lock_kernel();
+ lockdep_on();
return 0;
}
ntfs_error(sb, "Failed to allocate root directory.");
@@ -3059,6 +3089,7 @@
sb->s_fs_info = NULL;
kfree(vol);
ntfs_debug("Failed, returning -EINVAL.");
+ lockdep_on();
return -EINVAL;
}