From d614146d18159e54d4dfc289e4c1534ccc485cf2 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Thu, 28 Jul 2016 13:05:50 -0400
Subject: fold dentry_rcuwalk_invalidate() into its only remaining caller

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/dcache.c | 17 ++---------------
 1 file changed, 2 insertions(+), 15 deletions(-)

diff --git a/fs/dcache.c b/fs/dcache.c
index b90cf8e09d5b..6a629f50c3cf 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -316,20 +316,6 @@ static void dentry_free(struct dentry *dentry)
 		call_rcu(&dentry->d_u.d_rcu, __d_free);
 }
 
-/**
- * dentry_rcuwalk_invalidate - invalidate in-progress rcu-walk lookups
- * @dentry: the target dentry
- * After this call, in-progress rcu-walk path lookup will fail. This
- * should be called after unhashing, and after changing d_inode (if
- * the dentry has not already been unhashed).
- */
-static inline void dentry_rcuwalk_invalidate(struct dentry *dentry)
-{
-	lockdep_assert_held(&dentry->d_lock);
-	/* Go through am invalidation barrier */
-	write_seqcount_invalidate(&dentry->d_seq);
-}
-
 /*
  * Release the dentry's inode, using the filesystem
  * d_iput() operation if defined.
@@ -468,7 +454,8 @@ void __d_drop(struct dentry *dentry)
 		__hlist_bl_del(&dentry->d_hash);
 		dentry->d_hash.pprev = NULL;
 		hlist_bl_unlock(b);
-		dentry_rcuwalk_invalidate(dentry);
+		/* After this call, in-progress rcu-walk path lookup will fail. */
+		write_seqcount_invalidate(&dentry->d_seq);
 	}
 }
 EXPORT_SYMBOL(__d_drop);
-- 
cgit v1.2.3


From 15d3c589f6305c50a705572dbb33620c5cba416c Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 29 Jul 2016 17:45:21 -0400
Subject: fold _d_rehash() and __d_rehash() together

The only place where we feed to __d_rehash() something other than
d_hash(dentry->d_name.hash) is __d_move(), where we give it d_hash
of another dentry.  Postpone rehashing until we'd switched the
names and we are rid of that exception, along with the need to
keep _d_rehash() and __d_rehash() separate.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/dcache.c | 34 +++++++++++-----------------------
 1 file changed, 11 insertions(+), 23 deletions(-)

diff --git a/fs/dcache.c b/fs/dcache.c
index 6a629f50c3cf..d9450bd496ac 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -2339,19 +2339,15 @@ again:
 }
 EXPORT_SYMBOL(d_delete);
 
-static void __d_rehash(struct dentry * entry, struct hlist_bl_head *b)
+static void __d_rehash(struct dentry *entry)
 {
+	struct hlist_bl_head *b = d_hash(entry->d_name.hash);
 	BUG_ON(!d_unhashed(entry));
 	hlist_bl_lock(b);
 	hlist_bl_add_head_rcu(&entry->d_hash, b);
 	hlist_bl_unlock(b);
 }
 
-static void _d_rehash(struct dentry * entry)
-{
-	__d_rehash(entry, d_hash(entry->d_name.hash));
-}
-
 /**
  * d_rehash	- add an entry back to the hash
  * @entry: dentry to add to the hash
@@ -2362,7 +2358,7 @@ static void _d_rehash(struct dentry * entry)
 void d_rehash(struct dentry * entry)
 {
 	spin_lock(&entry->d_lock);
-	_d_rehash(entry);
+	__d_rehash(entry);
 	spin_unlock(&entry->d_lock);
 }
 EXPORT_SYMBOL(d_rehash);
@@ -2536,7 +2532,7 @@ static inline void __d_add(struct dentry *dentry, struct inode *inode)
 		raw_write_seqcount_end(&dentry->d_seq);
 		fsnotify_update_flags(dentry);
 	}
-	_d_rehash(dentry);
+	__d_rehash(dentry);
 	if (dir)
 		end_dir_add(dir, n);
 	spin_unlock(&dentry->d_lock);
@@ -2598,7 +2594,7 @@ struct dentry *d_exact_alias(struct dentry *entry, struct inode *inode)
 			alias = NULL;
 		} else {
 			__dget_dlock(alias);
-			_d_rehash(alias);
+			__d_rehash(alias);
 			spin_unlock(&alias->d_lock);
 		}
 		spin_unlock(&inode->i_lock);
@@ -2782,23 +2778,10 @@ static void __d_move(struct dentry *dentry, struct dentry *target,
 	write_seqcount_begin(&dentry->d_seq);
 	write_seqcount_begin_nested(&target->d_seq, DENTRY_D_LOCK_NESTED);
 
+	/* unhash both */
 	/* __d_drop does write_seqcount_barrier, but they're OK to nest. */
-
-	/*
-	 * Move the dentry to the target hash queue. Don't bother checking
-	 * for the same hash queue because of how unlikely it is.
-	 */
 	__d_drop(dentry);
-	__d_rehash(dentry, d_hash(target->d_name.hash));
-
-	/*
-	 * Unhash the target (d_delete() is not usable here).  If exchanging
-	 * the two dentries, then rehash onto the other's hash queue.
-	 */
 	__d_drop(target);
-	if (exchange) {
-		__d_rehash(target, d_hash(dentry->d_name.hash));
-	}
 
 	/* Switch the names.. */
 	if (exchange)
@@ -2806,6 +2789,11 @@ static void __d_move(struct dentry *dentry, struct dentry *target,
 	else
 		copy_name(dentry, target);
 
+	/* rehash in new place(s) */
+	__d_rehash(dentry);
+	if (exchange)
+		__d_rehash(target);
+
 	/* ... and switch them in the tree */
 	if (IS_ROOT(dentry)) {
 		/* splicing a tree */
-- 
cgit v1.2.3


From e0b3f595d13b3e9ce9cdf53935e7f304c04b5b2b Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 29 Jul 2016 18:22:49 -0400
Subject: affs ->d_compare(): don't bother with ->d_inode

Use ->d_sb directly.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/affs/amigaffs.c | 4 +---
 fs/affs/namei.c    | 4 ++--
 2 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/fs/affs/amigaffs.c b/fs/affs/amigaffs.c
index d6c7a51c93e4..d8f217c711d3 100644
--- a/fs/affs/amigaffs.c
+++ b/fs/affs/amigaffs.c
@@ -472,9 +472,7 @@ affs_warning(struct super_block *sb, const char *function, const char *fmt, ...)
 bool
 affs_nofilenametruncate(const struct dentry *dentry)
 {
-	struct inode *inode = d_inode(dentry);
-
-	return affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_NO_TRUNCATE);
+	return affs_test_opt(AFFS_SB(dentry->d_sb)->s_flags, SF_NO_TRUNCATE);
 }
 
 /* Check if the name is valid for a affs object. */
diff --git a/fs/affs/namei.c b/fs/affs/namei.c
index eb32029bc776..27ca732680d9 100644
--- a/fs/affs/namei.c
+++ b/fs/affs/namei.c
@@ -136,7 +136,7 @@ affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
 {
 
 	return __affs_compare_dentry(len, str, name, affs_toupper,
-				     affs_nofilenametruncate(parent));
+				     affs_nofilenametruncate(dentry));
 }
 
 static int
@@ -144,7 +144,7 @@ affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentr
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	return __affs_compare_dentry(len, str, name, affs_intl_toupper,
-				     affs_nofilenametruncate(parent));
+				     affs_nofilenametruncate(dentry));
 
 }
 
-- 
cgit v1.2.3


From d3fe19852e96aabe3084c82ec2f3fb4918ab6d1e Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 29 Jul 2016 18:23:59 -0400
Subject: cifs, msdos, vfat, hfs+: don't bother with parent in ->d_compare()

dentry->d_sb is just as good as parent->d_sb

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/cifs/dir.c        | 2 +-
 fs/fat/namei_msdos.c | 2 +-
 fs/fat/namei_vfat.c  | 2 +-
 fs/hfsplus/unicode.c | 2 +-
 fs/hpfs/dentry.c     | 2 +-
 5 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index 4e532536cbc6..cf394da87cd4 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -906,7 +906,7 @@ static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 static int cifs_ci_compare(const struct dentry *parent, const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
-	struct nls_table *codepage = CIFS_SB(parent->d_sb)->local_nls;
+	struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 	wchar_t c1, c2;
 	int i, l1, l2;
 
diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
index 1337c0c7527d..0f177127e4d6 100644
--- a/fs/fat/namei_msdos.c
+++ b/fs/fat/namei_msdos.c
@@ -165,7 +165,7 @@ static int msdos_hash(const struct dentry *dentry, struct qstr *qstr)
 static int msdos_cmp(const struct dentry *parent, const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
-	struct fat_mount_options *options = &MSDOS_SB(parent->d_sb)->options;
+	struct fat_mount_options *options = &MSDOS_SB(dentry->d_sb)->options;
 	unsigned char a_msdos_name[MSDOS_NAME], b_msdos_name[MSDOS_NAME];
 	int error;
 
diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index 6ccdf3f34f90..e60a90841381 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -141,7 +141,7 @@ static int vfat_hashi(const struct dentry *dentry, struct qstr *qstr)
 static int vfat_cmpi(const struct dentry *parent, const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
-	struct nls_table *t = MSDOS_SB(parent->d_sb)->nls_io;
+	struct nls_table *t = MSDOS_SB(dentry->d_sb)->nls_io;
 	unsigned int alen, blen;
 
 	/* A filename cannot end in '.' or we treat it like it has none */
diff --git a/fs/hfsplus/unicode.c b/fs/hfsplus/unicode.c
index c13c8a240be3..509d7e231460 100644
--- a/fs/hfsplus/unicode.c
+++ b/fs/hfsplus/unicode.c
@@ -388,7 +388,7 @@ int hfsplus_hash_dentry(const struct dentry *dentry, struct qstr *str)
 int hfsplus_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
-	struct super_block *sb = parent->d_sb;
+	struct super_block *sb = dentry->d_sb;
 	int casefold, decompose, size;
 	int dsize1, dsize2, len1, len2;
 	const u16 *dstr1, *dstr2;
diff --git a/fs/hpfs/dentry.c b/fs/hpfs/dentry.c
index 60e6d334d79a..a804300f4dce 100644
--- a/fs/hpfs/dentry.c
+++ b/fs/hpfs/dentry.c
@@ -50,7 +50,7 @@ static int hpfs_compare_dentry(const struct dentry *parent, const struct dentry
 
 	if (hpfs_chk_name(name->name, &bl))
 		return 1;
-	if (hpfs_compare_names(parent->d_sb, str, al, name->name, bl, 0))
+	if (hpfs_compare_names(dentry->d_sb, str, al, name->name, bl, 0))
 		return 1;
 	return 0;
 }
-- 
cgit v1.2.3


From 6fa67e707559303e086303aeecc9e8b91ef497d5 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sun, 31 Jul 2016 16:37:25 -0400
Subject: get rid of 'parent' argument of ->d_compare()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 Documentation/filesystems/Locking            |  2 +-
 Documentation/filesystems/porting            |  7 +++++++
 Documentation/filesystems/vfs.txt            |  2 +-
 drivers/staging/lustre/lustre/llite/dcache.c |  2 +-
 fs/adfs/dir.c                                |  2 +-
 fs/affs/namei.c                              |  8 ++++----
 fs/cifs/dir.c                                |  2 +-
 fs/dcache.c                                  |  4 ++--
 fs/efivarfs/super.c                          |  3 +--
 fs/fat/namei_msdos.c                         |  2 +-
 fs/fat/namei_vfat.c                          |  4 ++--
 fs/hfs/hfs_fs.h                              |  2 +-
 fs/hfs/string.c                              |  2 +-
 fs/hfsplus/hfsplus_fs.h                      |  3 +--
 fs/hfsplus/unicode.c                         |  2 +-
 fs/hpfs/dentry.c                             |  2 +-
 fs/isofs/inode.c                             | 15 ++++++---------
 fs/isofs/namei.c                             |  2 +-
 fs/jfs/namei.c                               |  2 +-
 fs/ncpfs/dir.c                               |  6 +++---
 fs/proc/proc_sysctl.c                        |  2 +-
 include/linux/dcache.h                       |  2 +-
 22 files changed, 40 insertions(+), 38 deletions(-)

diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 1b3c39a7de62..d30fb2cb5066 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -12,7 +12,7 @@ prototypes:
 	int (*d_revalidate)(struct dentry *, unsigned int);
 	int (*d_weak_revalidate)(struct dentry *, unsigned int);
 	int (*d_hash)(const struct dentry *, struct qstr *);
-	int (*d_compare)(const struct dentry *, const struct dentry *,
+	int (*d_compare)(const struct dentry *,
 			unsigned int, const char *, const struct qstr *);
 	int (*d_delete)(struct dentry *);
 	int (*d_init)(struct dentry *);
diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting
index a5fb89cac615..b1bd05ea66b2 100644
--- a/Documentation/filesystems/porting
+++ b/Documentation/filesystems/porting
@@ -585,3 +585,10 @@ in your dentry operations instead.
 	in the instances.  Rationale: !@#!@# security_d_instantiate() needs to be
 	called before we attach dentry to inode and !@#!@##!@$!$#!@#$!@$!@$ smack
 	->d_instantiate() uses not just ->getxattr() but ->setxattr() as well.
+--
+[mandatory]
+	->d_compare() doesn't get parent as a separate argument anymore.  If you
+	used it for finding the struct super_block involved, dentry->d_sb will
+	work just as well; if it's something more complicated, use dentry->d_parent.
+	Just be careful not to assume that fetching it more than once will yield
+	the same value - in RCU mode it could change under you.
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index 8a196851f01d..9ace359d6cc5 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -931,7 +931,7 @@ struct dentry_operations {
 	int (*d_revalidate)(struct dentry *, unsigned int);
 	int (*d_weak_revalidate)(struct dentry *, unsigned int);
 	int (*d_hash)(const struct dentry *, struct qstr *);
-	int (*d_compare)(const struct dentry *, const struct dentry *,
+	int (*d_compare)(const struct dentry *,
 			unsigned int, const char *, const struct qstr *);
 	int (*d_delete)(const struct dentry *);
 	int (*d_init)(struct dentry *);
diff --git a/drivers/staging/lustre/lustre/llite/dcache.c b/drivers/staging/lustre/lustre/llite/dcache.c
index 581a63a0a63e..463b1a360733 100644
--- a/drivers/staging/lustre/lustre/llite/dcache.c
+++ b/drivers/staging/lustre/lustre/llite/dcache.c
@@ -78,7 +78,7 @@ static void ll_release(struct dentry *de)
  * INVALID) so d_lookup() matches it, but we have no lock on it (so
  * lock_match() fails) and we spin around real_lookup().
  */
-static int ll_dcompare(const struct dentry *parent, const struct dentry *dentry,
+static int ll_dcompare(const struct dentry *dentry,
 		       unsigned int len, const char *str,
 		       const struct qstr *name)
 {
diff --git a/fs/adfs/dir.c b/fs/adfs/dir.c
index bec25f7017c0..c30a5a65cbb5 100644
--- a/fs/adfs/dir.c
+++ b/fs/adfs/dir.c
@@ -227,7 +227,7 @@ adfs_hash(const struct dentry *parent, struct qstr *qstr)
  * requirements of the underlying filesystem.
  */
 static int
-adfs_compare(const struct dentry *parent, const struct dentry *dentry,
+adfs_compare(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	int i;
diff --git a/fs/affs/namei.c b/fs/affs/namei.c
index 27ca732680d9..a2d68f828d53 100644
--- a/fs/affs/namei.c
+++ b/fs/affs/namei.c
@@ -14,11 +14,11 @@ typedef int (*toupper_t)(int);
 
 static int	 affs_toupper(int ch);
 static int	 affs_hash_dentry(const struct dentry *, struct qstr *);
-static int       affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+static int       affs_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name);
 static int	 affs_intl_toupper(int ch);
 static int	 affs_intl_hash_dentry(const struct dentry *, struct qstr *);
-static int       affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+static int       affs_intl_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name);
 
 const struct dentry_operations affs_dentry_operations = {
@@ -131,7 +131,7 @@ static inline int __affs_compare_dentry(unsigned int len,
 }
 
 static int
-affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+affs_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 
@@ -140,7 +140,7 @@ affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
 }
 
 static int
-affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+affs_intl_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	return __affs_compare_dentry(len, str, name, affs_intl_toupper,
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index cf394da87cd4..4716c54dbfc6 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -903,7 +903,7 @@ static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 	return 0;
 }
 
-static int cifs_ci_compare(const struct dentry *parent, const struct dentry *dentry,
+static int cifs_ci_compare(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
diff --git a/fs/dcache.c b/fs/dcache.c
index d9450bd496ac..32a9209c8138 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -2047,7 +2047,7 @@ static inline bool d_same_name(const struct dentry *dentry,
 			return false;
 		return dentry_cmp(dentry, name->name, name->len) == 0;
 	}
-	return parent->d_op->d_compare(parent, dentry,
+	return parent->d_op->d_compare(dentry,
 				       dentry->d_name.len, dentry->d_name.name,
 				       name) == 0;
 }
@@ -2150,7 +2150,7 @@ seqretry:
 				cpu_relax();
 				goto seqretry;
 			}
-			if (parent->d_op->d_compare(parent, dentry,
+			if (parent->d_op->d_compare(dentry,
 						    tlen, tname, name) != 0)
 				continue;
 		} else {
diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c
index a5e607e8f056..688ccc16b702 100644
--- a/fs/efivarfs/super.c
+++ b/fs/efivarfs/super.c
@@ -45,8 +45,7 @@ static struct super_block *efivarfs_sb;
  * So we need to perform a case-sensitive match on part 1 and a
  * case-insensitive match on part 2.
  */
-static int efivarfs_d_compare(const struct dentry *parent,
-			      const struct dentry *dentry,
+static int efivarfs_d_compare(const struct dentry *dentry,
 			      unsigned int len, const char *str,
 			      const struct qstr *name)
 {
diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
index 0f177127e4d6..664655b2c55f 100644
--- a/fs/fat/namei_msdos.c
+++ b/fs/fat/namei_msdos.c
@@ -162,7 +162,7 @@ static int msdos_hash(const struct dentry *dentry, struct qstr *qstr)
  * Compare two msdos names. If either of the names are invalid,
  * we fall back to doing the standard name comparison.
  */
-static int msdos_cmp(const struct dentry *parent, const struct dentry *dentry,
+static int msdos_cmp(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	struct fat_mount_options *options = &MSDOS_SB(dentry->d_sb)->options;
diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index e60a90841381..0335e504e65a 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -138,7 +138,7 @@ static int vfat_hashi(const struct dentry *dentry, struct qstr *qstr)
 /*
  * Case insensitive compare of two vfat names.
  */
-static int vfat_cmpi(const struct dentry *parent, const struct dentry *dentry,
+static int vfat_cmpi(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	struct nls_table *t = MSDOS_SB(dentry->d_sb)->nls_io;
@@ -157,7 +157,7 @@ static int vfat_cmpi(const struct dentry *parent, const struct dentry *dentry,
 /*
  * Case sensitive compare of two vfat names.
  */
-static int vfat_cmp(const struct dentry *parent, const struct dentry *dentry,
+static int vfat_cmp(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	unsigned int alen, blen;
diff --git a/fs/hfs/hfs_fs.h b/fs/hfs/hfs_fs.h
index ee2f385811c8..f28d7a259105 100644
--- a/fs/hfs/hfs_fs.h
+++ b/fs/hfs/hfs_fs.h
@@ -233,7 +233,7 @@ extern const struct dentry_operations hfs_dentry_operations;
 extern int hfs_hash_dentry(const struct dentry *, struct qstr *);
 extern int hfs_strcmp(const unsigned char *, unsigned int,
 		      const unsigned char *, unsigned int);
-extern int hfs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+extern int hfs_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name);
 
 /* trans.c */
diff --git a/fs/hfs/string.c b/fs/hfs/string.c
index ec9f164c35a5..3912209153a8 100644
--- a/fs/hfs/string.c
+++ b/fs/hfs/string.c
@@ -92,7 +92,7 @@ int hfs_strcmp(const unsigned char *s1, unsigned int len1,
  * Test for equality of two strings in the HFS filename character ordering.
  * return 1 on failure and 0 on success
  */
-int hfs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+int hfs_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	const unsigned char *n1, *n2;
diff --git a/fs/hfsplus/hfsplus_fs.h b/fs/hfsplus/hfsplus_fs.h
index 047245bd2cd6..e95c01f1d62e 100644
--- a/fs/hfsplus/hfsplus_fs.h
+++ b/fs/hfsplus/hfsplus_fs.h
@@ -520,8 +520,7 @@ int hfsplus_uni2asc(struct super_block *sb, const struct hfsplus_unistr *ustr,
 int hfsplus_asc2uni(struct super_block *sb, struct hfsplus_unistr *ustr,
 		    int max_unistr_len, const char *astr, int len);
 int hfsplus_hash_dentry(const struct dentry *dentry, struct qstr *str);
-int hfsplus_compare_dentry(const struct dentry *parent,
-			   const struct dentry *dentry, unsigned int len,
+int hfsplus_compare_dentry(const struct dentry *dentry, unsigned int len,
 			   const char *str, const struct qstr *name);
 
 /* wrapper.c */
diff --git a/fs/hfsplus/unicode.c b/fs/hfsplus/unicode.c
index 509d7e231460..e563939882f3 100644
--- a/fs/hfsplus/unicode.c
+++ b/fs/hfsplus/unicode.c
@@ -385,7 +385,7 @@ int hfsplus_hash_dentry(const struct dentry *dentry, struct qstr *str)
  * Composed unicode characters are decomposed and case-folding is performed
  * if the appropriate bits are (un)set on the superblock.
  */
-int hfsplus_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+int hfsplus_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	struct super_block *sb = dentry->d_sb;
diff --git a/fs/hpfs/dentry.c b/fs/hpfs/dentry.c
index a804300f4dce..bb87d65f0d97 100644
--- a/fs/hpfs/dentry.c
+++ b/fs/hpfs/dentry.c
@@ -34,7 +34,7 @@ static int hpfs_hash_dentry(const struct dentry *dentry, struct qstr *qstr)
 	return 0;
 }
 
-static int hpfs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+static int hpfs_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	unsigned al = len;
diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index 761fade7680f..ad0c745ebad7 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -29,18 +29,15 @@
 #define BEQUIET
 
 static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
-static int isofs_dentry_cmpi(const struct dentry *parent,
-		const struct dentry *dentry,
+static int isofs_dentry_cmpi(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name);
 
 #ifdef CONFIG_JOLIET
 static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
 static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
-static int isofs_dentry_cmpi_ms(const struct dentry *parent,
-		const struct dentry *dentry,
+static int isofs_dentry_cmpi_ms(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name);
-static int isofs_dentry_cmp_ms(const struct dentry *parent,
-		const struct dentry *dentry,
+static int isofs_dentry_cmp_ms(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name);
 #endif
 
@@ -235,7 +232,7 @@ isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
 }
 
 static int
-isofs_dentry_cmpi(const struct dentry *parent, const struct dentry *dentry,
+isofs_dentry_cmpi(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	return isofs_dentry_cmp_common(len, str, name, 0, 1);
@@ -276,14 +273,14 @@ isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
 }
 
 static int
-isofs_dentry_cmp_ms(const struct dentry *parent, const struct dentry *dentry,
+isofs_dentry_cmp_ms(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	return isofs_dentry_cmp_common(len, str, name, 1, 0);
 }
 
 static int
-isofs_dentry_cmpi_ms(const struct dentry *parent, const struct dentry *dentry,
+isofs_dentry_cmpi_ms(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	return isofs_dentry_cmp_common(len, str, name, 1, 1);
diff --git a/fs/isofs/namei.c b/fs/isofs/namei.c
index 7b543e6b6526..aee592767f1d 100644
--- a/fs/isofs/namei.c
+++ b/fs/isofs/namei.c
@@ -22,7 +22,7 @@ isofs_cmp(struct dentry *dentry, const char *compare, int dlen)
 	qstr.len = dlen;
 	if (likely(!dentry->d_op))
 		return dentry->d_name.len != dlen || memcmp(dentry->d_name.name, compare, dlen);
-	return dentry->d_op->d_compare(NULL, NULL, dentry->d_name.len, dentry->d_name.name, &qstr);
+	return dentry->d_op->d_compare(NULL, dentry->d_name.len, dentry->d_name.name, &qstr);
 }
 
 /*
diff --git a/fs/jfs/namei.c b/fs/jfs/namei.c
index 04baf0dfc40c..814b0c58016c 100644
--- a/fs/jfs/namei.c
+++ b/fs/jfs/namei.c
@@ -1572,7 +1572,7 @@ static int jfs_ci_hash(const struct dentry *dir, struct qstr *this)
 	return 0;
 }
 
-static int jfs_ci_compare(const struct dentry *parent, const struct dentry *dentry,
+static int jfs_ci_compare(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	int i, result = 1;
diff --git a/fs/ncpfs/dir.c b/fs/ncpfs/dir.c
index 9add7ab747a5..17de5c13dfae 100644
--- a/fs/ncpfs/dir.c
+++ b/fs/ncpfs/dir.c
@@ -74,7 +74,7 @@ const struct inode_operations ncp_dir_inode_operations =
  */
 static int ncp_lookup_validate(struct dentry *, unsigned int);
 static int ncp_hash_dentry(const struct dentry *, struct qstr *);
-static int ncp_compare_dentry(const struct dentry *, const struct dentry *,
+static int ncp_compare_dentry(const struct dentry *,
 		unsigned int, const char *, const struct qstr *);
 static int ncp_delete_dentry(const struct dentry *);
 static void ncp_d_prune(struct dentry *dentry);
@@ -154,7 +154,7 @@ ncp_hash_dentry(const struct dentry *dentry, struct qstr *this)
  * the callers will handle races.
  */
 static int
-ncp_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+ncp_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	struct inode *pinode;
@@ -162,7 +162,7 @@ ncp_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
 	if (len != name->len)
 		return 1;
 
-	pinode = d_inode_rcu(parent);
+	pinode = d_inode_rcu(dentry->d_parent);
 	if (!pinode)
 		return 1;
 
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index b59db94d2ff4..30bb00130d0f 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -834,7 +834,7 @@ static int sysctl_is_seen(struct ctl_table_header *p)
 	return res;
 }
 
-static int proc_sys_compare(const struct dentry *parent, const struct dentry *dentry,
+static int proc_sys_compare(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	struct ctl_table_header *head;
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index 98044a8d1487..107d9abe7166 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -130,7 +130,7 @@ struct dentry_operations {
 	int (*d_revalidate)(struct dentry *, unsigned int);
 	int (*d_weak_revalidate)(struct dentry *, unsigned int);
 	int (*d_hash)(const struct dentry *, struct qstr *);
-	int (*d_compare)(const struct dentry *, const struct dentry *,
+	int (*d_compare)(const struct dentry *,
 			unsigned int, const char *, const struct qstr *);
 	int (*d_delete)(const struct dentry *);
 	int (*d_init)(struct dentry *);
-- 
cgit v1.2.3


From c1892c37769cf89c7e7ba57528ae2ccb5d153c9b Mon Sep 17 00:00:00 2001
From: Miklos Szeredi <mszeredi@redhat.com>
Date: Wed, 3 Aug 2016 13:44:27 +0200
Subject: vfs: fix deadlock in file_remove_privs() on overlayfs

file_remove_privs() is called with inode lock on file_inode(), which
proceeds to calling notify_change() on file->f_path.dentry.  Which triggers
the WARN_ON_ONCE(!inode_is_locked(inode)) in addition to deadlocking later
when ovl_setattr tries to lock the underlying inode again.

Fix this mess by not mixing the layers, but doing everything on underlying
dentry/inode.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 07a2daab49c5 ("ovl: Copy up underlying inode's ->i_mode to overlay inode")
Cc: <stable@vger.kernel.org>
---
 fs/inode.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/inode.c b/fs/inode.c
index 4ccbc21b30ce..68db39050446 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1740,8 +1740,8 @@ static int __remove_privs(struct dentry *dentry, int kill)
  */
 int file_remove_privs(struct file *file)
 {
-	struct dentry *dentry = file->f_path.dentry;
-	struct inode *inode = d_inode(dentry);
+	struct dentry *dentry = file_dentry(file);
+	struct inode *inode = file_inode(file);
 	int kill;
 	int error = 0;
 
@@ -1749,7 +1749,7 @@ int file_remove_privs(struct file *file)
 	if (IS_NOSEC(inode))
 		return 0;
 
-	kill = file_needs_remove_privs(file);
+	kill = dentry_needs_remove_privs(dentry);
 	if (kill < 0)
 		return kill;
 	if (kill)
-- 
cgit v1.2.3


From 3e5a4c94a4f88b545d64bbfc7647b06b92c66e98 Mon Sep 17 00:00:00 2001
From: Miklos Szeredi <mszeredi@redhat.com>
Date: Wed, 3 Aug 2016 13:44:27 +0200
Subject: vfs: remove file_needs_remove_privs()

This function is now unused.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
---
 include/linux/fs.h | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index dd288148a6b1..3888341913ef 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2726,10 +2726,6 @@ extern void free_inode_nonrcu(struct inode *inode);
 extern int should_remove_suid(struct dentry *);
 extern int file_remove_privs(struct file *);
 extern int dentry_needs_remove_privs(struct dentry *dentry);
-static inline int file_needs_remove_privs(struct file *file)
-{
-	return dentry_needs_remove_privs(file->f_path.dentry);
-}
 
 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
 static inline void insert_inode_hash(struct inode *inode)
-- 
cgit v1.2.3


From f0fce87c36aec5c4a895c78b76396f5727047b93 Mon Sep 17 00:00:00 2001
From: Miklos Szeredi <mszeredi@redhat.com>
Date: Wed, 3 Aug 2016 13:44:27 +0200
Subject: vfs: make dentry_needs_remove_privs() internal

Only used by the vfs.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
---
 fs/inode.c         | 1 -
 fs/internal.h      | 1 +
 include/linux/fs.h | 1 -
 3 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/inode.c b/fs/inode.c
index 68db39050446..2029357fcf97 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1720,7 +1720,6 @@ int dentry_needs_remove_privs(struct dentry *dentry)
 		mask |= ATTR_KILL_PRIV;
 	return mask;
 }
-EXPORT_SYMBOL(dentry_needs_remove_privs);
 
 static int __remove_privs(struct dentry *dentry, int kill)
 {
diff --git a/fs/internal.h b/fs/internal.h
index f57ced528cde..30b568f02613 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -114,6 +114,7 @@ extern int vfs_open(const struct path *, struct file *, const struct cred *);
  */
 extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc);
 extern void inode_add_lru(struct inode *inode);
+extern int dentry_needs_remove_privs(struct dentry *dentry);
 
 /*
  * fs-writeback.c
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 3888341913ef..448641bcafc5 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2725,7 +2725,6 @@ extern struct inode *new_inode(struct super_block *sb);
 extern void free_inode_nonrcu(struct inode *inode);
 extern int should_remove_suid(struct dentry *);
 extern int file_remove_privs(struct file *);
-extern int dentry_needs_remove_privs(struct dentry *dentry);
 
 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
 static inline void insert_inode_hash(struct inode *inode)
-- 
cgit v1.2.3


From 797fc16d8f00bf681b7f9969c0701725b472b11a Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Wed, 3 Aug 2016 11:02:48 -0400
Subject: 9p: fix braino introduced in "9p: new helper - v9fs_parent_fid()"

In v9fs_vfs_rename() we need to clone the parents' fids, not just
find them.

Spotted-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/9p/fid.h       | 4 ++++
 fs/9p/vfs_inode.c | 4 ++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/9p/fid.h b/fs/9p/fid.h
index 12700df0bb51..d4c5002d56ad 100644
--- a/fs/9p/fid.h
+++ b/fs/9p/fid.h
@@ -31,4 +31,8 @@ static inline struct p9_fid *v9fs_parent_fid(struct dentry *dentry)
 struct p9_fid *v9fs_fid_clone(struct dentry *dentry);
 void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid);
 struct p9_fid *v9fs_writeback_fid(struct dentry *dentry);
+static inline struct p9_fid *clone_fid(struct p9_fid *fid)
+{
+	return IS_ERR(fid) ? fid :  p9_client_walk(fid, 0, NULL, 1);
+}
 #endif
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 7da9a8354fad..26189eebcd1c 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -975,13 +975,13 @@ v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	if (IS_ERR(oldfid))
 		return PTR_ERR(oldfid);
 
-	olddirfid = v9fs_parent_fid(old_dentry);
+	olddirfid = clone_fid(v9fs_parent_fid(old_dentry));
 	if (IS_ERR(olddirfid)) {
 		retval = PTR_ERR(olddirfid);
 		goto done;
 	}
 
-	newdirfid = v9fs_parent_fid(new_dentry);
+	newdirfid = clone_fid(v9fs_parent_fid(new_dentry));
 	if (IS_ERR(newdirfid)) {
 		retval = PTR_ERR(newdirfid);
 		goto clunk_olddir;
-- 
cgit v1.2.3


From 7d50a29fe43848b7d3c8309f8617db3305c0db18 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Wed, 3 Aug 2016 11:12:12 -0400
Subject: 9p: use clone_fid()

in a bunch of places it cleans the things up

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/9p/fid.c            | 26 +-------------------------
 fs/9p/fid.h            |  5 ++++-
 fs/9p/vfs_inode.c      |  2 +-
 fs/9p/vfs_inode_dotl.c |  2 +-
 fs/9p/xattr.c          |  4 +---
 5 files changed, 8 insertions(+), 31 deletions(-)

diff --git a/fs/9p/fid.c b/fs/9p/fid.c
index 47db55aee7f2..60fb47469c86 100644
--- a/fs/9p/fid.c
+++ b/fs/9p/fid.c
@@ -257,36 +257,12 @@ struct p9_fid *v9fs_fid_lookup(struct dentry *dentry)
 	return v9fs_fid_lookup_with_uid(dentry, uid, any);
 }
 
-struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
-{
-	struct p9_fid *fid, *ret;
-
-	fid = v9fs_fid_lookup(dentry);
-	if (IS_ERR(fid))
-		return fid;
-
-	ret = p9_client_walk(fid, 0, NULL, 1);
-	return ret;
-}
-
-static struct p9_fid *v9fs_fid_clone_with_uid(struct dentry *dentry, kuid_t uid)
-{
-	struct p9_fid *fid, *ret;
-
-	fid = v9fs_fid_lookup_with_uid(dentry, uid, 0);
-	if (IS_ERR(fid))
-		return fid;
-
-	ret = p9_client_walk(fid, 0, NULL, 1);
-	return ret;
-}
-
 struct p9_fid *v9fs_writeback_fid(struct dentry *dentry)
 {
 	int err;
 	struct p9_fid *fid;
 
-	fid = v9fs_fid_clone_with_uid(dentry, GLOBAL_ROOT_UID);
+	fid = clone_fid(v9fs_fid_lookup_with_uid(dentry, GLOBAL_ROOT_UID, 0));
 	if (IS_ERR(fid))
 		goto error_out;
 	/*
diff --git a/fs/9p/fid.h b/fs/9p/fid.h
index d4c5002d56ad..4491bcaf42b8 100644
--- a/fs/9p/fid.h
+++ b/fs/9p/fid.h
@@ -28,11 +28,14 @@ static inline struct p9_fid *v9fs_parent_fid(struct dentry *dentry)
 {
 	return v9fs_fid_lookup(dentry->d_parent);
 }
-struct p9_fid *v9fs_fid_clone(struct dentry *dentry);
 void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid);
 struct p9_fid *v9fs_writeback_fid(struct dentry *dentry);
 static inline struct p9_fid *clone_fid(struct p9_fid *fid)
 {
 	return IS_ERR(fid) ? fid :  p9_client_walk(fid, 0, NULL, 1);
 }
+static inline struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
+{
+	return clone_fid(v9fs_fid_lookup(dentry));
+}
 #endif
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 26189eebcd1c..8b1999b528e9 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -661,7 +661,7 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
 	}
 
 	/* clone a fid to use for creation */
-	ofid = p9_client_walk(dfid, 0, NULL, 1);
+	ofid = clone_fid(dfid);
 	if (IS_ERR(ofid)) {
 		err = PTR_ERR(ofid);
 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 2ed04c2fe7af..eeabcb0bad12 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -281,7 +281,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
 	}
 
 	/* clone a fid to use for creation */
-	ofid = p9_client_walk(dfid, 0, NULL, 1);
+	ofid = clone_fid(dfid);
 	if (IS_ERR(ofid)) {
 		err = PTR_ERR(ofid);
 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
diff --git a/fs/9p/xattr.c b/fs/9p/xattr.c
index a6bd349bab23..f329eee6dc93 100644
--- a/fs/9p/xattr.c
+++ b/fs/9p/xattr.c
@@ -97,8 +97,6 @@ int v9fs_xattr_set(struct dentry *dentry, const char *name,
 		   const void *value, size_t value_len, int flags)
 {
 	struct p9_fid *fid = v9fs_fid_lookup(dentry);
-	if (IS_ERR(fid))
-		return PTR_ERR(fid);
 	return v9fs_fid_xattr_set(fid, name, value, value_len, flags);
 }
 
@@ -115,7 +113,7 @@ int v9fs_fid_xattr_set(struct p9_fid *fid, const char *name,
 		 name, value_len, flags);
 
 	/* Clone it */
-	fid = p9_client_walk(fid, 0, NULL, 1);
+	fid = clone_fid(fid);
 	if (IS_ERR(fid))
 		return PTR_ERR(fid);
 
-- 
cgit v1.2.3


From db20a8925bc420eed033c5d91ff6afa74465e521 Mon Sep 17 00:00:00 2001
From: David Howells <dhowells@redhat.com>
Date: Wed, 3 Aug 2016 17:57:39 +0100
Subject: cachefiles: Fix race between inactivating and culling a cache object

There's a race between cachefiles_mark_object_inactive() and
cachefiles_cull():

 (1) cachefiles_cull() can't delete a backing file until the cache object
     is marked inactive, but as soon as that's the case it's fair game.

 (2) cachefiles_mark_object_inactive() marks the object as being inactive
     and *only then* reads the i_blocks on the backing inode - but
     cachefiles_cull() might've managed to delete it by this point.

Fix this by making sure cachefiles_mark_object_inactive() gets any data it
needs from the backing inode before deactivating the object.

Without this, the following oops may occur:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000098
IP: [<ffffffffa06c5cc1>] cachefiles_mark_object_inactive+0x61/0xb0 [cachefiles]
...
CPU: 11 PID: 527 Comm: kworker/u64:4 Tainted: G          I    ------------   3.10.0-470.el7.x86_64 #1
Hardware name: Hewlett-Packard HP Z600 Workstation/0B54h, BIOS 786G4 v03.19 03/11/2011
Workqueue: fscache_object fscache_object_work_func [fscache]
task: ffff880035edaf10 ti: ffff8800b77c0000 task.ti: ffff8800b77c0000
RIP: 0010:[<ffffffffa06c5cc1>] cachefiles_mark_object_inactive+0x61/0xb0 [cachefiles]
RSP: 0018:ffff8800b77c3d70  EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8800bf6cc400 RCX: 0000000000000034
RDX: 0000000000000000 RSI: ffff880090ffc710 RDI: ffff8800bf761ef8
RBP: ffff8800b77c3d88 R08: 2000000000000000 R09: 0090ffc710000000
R10: ff51005d2ff1c400 R11: 0000000000000000 R12: ffff880090ffc600
R13: ffff8800bf6cc520 R14: ffff8800bf6cc400 R15: ffff8800bf6cc498
FS:  0000000000000000(0000) GS:ffff8800bb8c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000098 CR3: 00000000019ba000 CR4: 00000000000007e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
 ffff880090ffc600 ffff8800bf6cc400 ffff8800867df140 ffff8800b77c3db0
 ffffffffa06c48cb ffff880090ffc600 ffff880090ffc180 ffff880090ffc658
 ffff8800b77c3df0 ffffffffa085d846 ffff8800a96b8150 ffff880090ffc600
Call Trace:
 [<ffffffffa06c48cb>] cachefiles_drop_object+0x6b/0xf0 [cachefiles]
 [<ffffffffa085d846>] fscache_drop_object+0xd6/0x1e0 [fscache]
 [<ffffffffa085d615>] fscache_object_work_func+0xa5/0x200 [fscache]
 [<ffffffff810a605b>] process_one_work+0x17b/0x470
 [<ffffffff810a6e96>] worker_thread+0x126/0x410
 [<ffffffff810a6d70>] ? rescuer_thread+0x460/0x460
 [<ffffffff810ae64f>] kthread+0xcf/0xe0
 [<ffffffff810ae580>] ? kthread_create_on_node+0x140/0x140
 [<ffffffff81695418>] ret_from_fork+0x58/0x90
 [<ffffffff810ae580>] ? kthread_create_on_node+0x140/0x140

The oopsing code shows:

	callq  0xffffffff810af6a0 <wake_up_bit>
	mov    0xf8(%r12),%rax
	mov    0x30(%rax),%rax
	mov    0x98(%rax),%rax   <---- oops here
	lock add %rax,0x130(%rbx)

where this is:

	d_backing_inode(object->dentry)->i_blocks

Fixes: a5b3a80b899bda0f456f1246c4c5a1191ea01519 (CacheFiles: Provide read-and-reset release counters for cachefilesd)
Reported-by: Jianhong Yin <jiyin@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/cachefiles/namei.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c
index 4ae75006e73b..3f7c2cd41f8f 100644
--- a/fs/cachefiles/namei.c
+++ b/fs/cachefiles/namei.c
@@ -263,6 +263,8 @@ requeue:
 void cachefiles_mark_object_inactive(struct cachefiles_cache *cache,
 				     struct cachefiles_object *object)
 {
+	blkcnt_t i_blocks = d_backing_inode(object->dentry)->i_blocks;
+
 	write_lock(&cache->active_lock);
 	rb_erase(&object->active_node, &cache->active_nodes);
 	clear_bit(CACHEFILES_OBJECT_ACTIVE, &object->flags);
@@ -273,8 +275,7 @@ void cachefiles_mark_object_inactive(struct cachefiles_cache *cache,
 	/* This object can now be culled, so we need to let the daemon know
 	 * that there is something it can remove if it needs to.
 	 */
-	atomic_long_add(d_backing_inode(object->dentry)->i_blocks,
-			&cache->b_released);
+	atomic_long_add(i_blocks, &cache->b_released);
 	if (atomic_inc_return(&cache->f_released))
 		cachefiles_state_changed(cache);
 }
-- 
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