Merge branch 'locks-3.15' of git://git.samba.org/jlayton/linux

Pull file locking updates from Jeff Layton:
 "Highlights:

   - maintainership change for fs/locks.c.  Willy's not interested in
     maintaining it these days, and is OK with Bruce and I taking it.
   - fix for open vs setlease race that Al ID'ed
   - cleanup and consolidation of file locking code
   - eliminate unneeded BUG() call
   - merge of file-private lock implementation"

* 'locks-3.15' of git://git.samba.org/jlayton/linux:
  locks: make locks_mandatory_area check for file-private locks
  locks: fix locks_mandatory_locked to respect file-private locks
  locks: require that flock->l_pid be set to 0 for file-private locks
  locks: add new fcntl cmd values for handling file private locks
  locks: skip deadlock detection on FL_FILE_PVT locks
  locks: pass the cmd value to fcntl_getlk/getlk64
  locks: report l_pid as -1 for FL_FILE_PVT locks
  locks: make /proc/locks show IS_FILE_PVT locks as type "FLPVT"
  locks: rename locks_remove_flock to locks_remove_file
  locks: consolidate checks for compatible filp->f_mode values in setlk handlers
  locks: fix posix lock range overflow handling
  locks: eliminate BUG() call when there's an unexpected lock on file close
  locks: add __acquires and __releases annotations to locks_start and locks_stop
  locks: remove "inline" qualifier from fl_link manipulation functions
  locks: clean up comment typo
  locks: close potential race between setlease and open
  MAINTAINERS: update entry for fs/locks.c

2 files changed, 42 insertions, 20 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 215cb1b09f47..a877ed3f389f 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -893,6 +893,7 @@ static inline int file_check_writeable(struct file *filp)
 #define FL_SLEEP	128	/* A blocking lock */
 #define FL_DOWNGRADE_PENDING	256 /* Lease is being downgraded */
 #define FL_UNLOCK_PENDING	512 /* Lease is being broken */
+#define FL_FILE_PVT	1024	/* lock is private to the file */
 
 /*
  * Special return value from posix_lock_file() and vfs_lock_file() for
@@ -997,12 +998,12 @@ struct file_lock {
 extern void send_sigio(struct fown_struct *fown, int fd, int band);
 
 #ifdef CONFIG_FILE_LOCKING
-extern int fcntl_getlk(struct file *, struct flock __user *);
+extern int fcntl_getlk(struct file *, unsigned int, struct flock __user *);
 extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
 			struct flock __user *);
 
 #if BITS_PER_LONG == 32
-extern int fcntl_getlk64(struct file *, struct flock64 __user *);
+extern int fcntl_getlk64(struct file *, unsigned int, struct flock64 __user *);
 extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
 			struct flock64 __user *);
 #endif
@@ -1017,7 +1018,7 @@ extern struct file_lock * locks_alloc_lock(void);
 extern void locks_copy_lock(struct file_lock *, struct file_lock *);
 extern void __locks_copy_lock(struct file_lock *, const struct file_lock *);
 extern void locks_remove_posix(struct file *, fl_owner_t);
-extern void locks_remove_flock(struct file *);
+extern void locks_remove_file(struct file *);
 extern void locks_release_private(struct file_lock *);
 extern void posix_test_lock(struct file *, struct file_lock *);
 extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
@@ -1035,7 +1036,8 @@ extern int lease_modify(struct file_lock **, int);
 extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
 extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
 #else /* !CONFIG_FILE_LOCKING */
-static inline int fcntl_getlk(struct file *file, struct flock __user *user)
+static inline int fcntl_getlk(struct file *file, unsigned int cmd,
+			      struct flock __user *user)
 {
 	return -EINVAL;
 }
@@ -1047,7 +1049,8 @@ static inline int fcntl_setlk(unsigned int fd, struct file *file,
 }
 
 #if BITS_PER_LONG == 32
-static inline int fcntl_getlk64(struct file *file, struct flock64 __user *user)
+static inline int fcntl_getlk64(struct file *file, unsigned int cmd,
+				struct flock64 __user *user)
 {
 	return -EINVAL;
 }
@@ -1088,7 +1091,7 @@ static inline void locks_remove_posix(struct file *filp, fl_owner_t owner)
 	return;
 }
 
-static inline void locks_remove_flock(struct file *filp)
+static inline void locks_remove_file(struct file *filp)
 {
 	return;
 }
@@ -1916,6 +1919,11 @@ extern int current_umask(void);
 extern void ihold(struct inode * inode);
 extern void iput(struct inode *);
 
+static inline struct inode *file_inode(struct file *f)
+{
+	return f->f_inode;
+}
+
 /* /sys/fs */
 extern struct kobject *fs_kobj;
 
@@ -1925,7 +1933,7 @@ extern struct kobject *fs_kobj;
 #define FLOCK_VERIFY_WRITE 2
 
 #ifdef CONFIG_FILE_LOCKING
-extern int locks_mandatory_locked(struct inode *);
+extern int locks_mandatory_locked(struct file *);
 extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
 
 /*
@@ -1948,10 +1956,10 @@ static inline int mandatory_lock(struct inode *ino)
 	return IS_MANDLOCK(ino) && __mandatory_lock(ino);
 }
 
-static inline int locks_verify_locked(struct inode *inode)
+static inline int locks_verify_locked(struct file *file)
 {
-	if (mandatory_lock(inode))
-		return locks_mandatory_locked(inode);
+	if (mandatory_lock(file_inode(file)))
+		return locks_mandatory_locked(file);
 	return 0;
 }
 
@@ -1971,6 +1979,12 @@ static inline int locks_verify_truncate(struct inode *inode,
 
 static inline int break_lease(struct inode *inode, unsigned int mode)
 {
+	/*
+	 * Since this check is lockless, we must ensure that any refcounts
+	 * taken are done before checking inode->i_flock. Otherwise, we could
+	 * end up racing with tasks trying to set a new lease on this file.
+	 */
+	smp_mb();
 	if (inode->i_flock)
 		return __break_lease(inode, mode, FL_LEASE);
 	return 0;
@@ -2006,7 +2020,7 @@ static inline int break_deleg_wait(struct inode **delegated_inode)
 }
 
 #else /* !CONFIG_FILE_LOCKING */
-static inline int locks_mandatory_locked(struct inode *inode)
+static inline int locks_mandatory_locked(struct file *file)
 {
 	return 0;
 }
@@ -2028,7 +2042,7 @@ static inline int mandatory_lock(struct inode *inode)
 	return 0;
 }
 
-static inline int locks_verify_locked(struct inode *inode)
+static inline int locks_verify_locked(struct file *file)
 {
 	return 0;
 }
@@ -2302,11 +2316,6 @@ static inline bool execute_ok(struct inode *inode)
 	return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
 }
 
-static inline struct inode *file_inode(struct file *f)
-{
-	return f->f_inode;
-}
-
 static inline void file_start_write(struct file *file)
 {
 	if (!S_ISREG(file_inode(file)->i_mode))
diff --git a/include/uapi/asm-generic/fcntl.h b/include/uapi/asm-generic/fcntl.h
index 95e46c8e05f9..a9b13f8b3595 100644
--- a/include/uapi/asm-generic/fcntl.h
+++ b/include/uapi/asm-generic/fcntl.h
@@ -132,6 +132,22 @@
 #define F_GETOWNER_UIDS	17
 #endif
 
+/*
+ * fd "private" POSIX locks.
+ *
+ * Usually POSIX locks held by a process are released on *any* close and are
+ * not inherited across a fork().
+ *
+ * These cmd values will set locks that conflict with normal POSIX locks, but
+ * are "owned" by the opened file, not the process. This means that they are
+ * inherited across fork() like BSD (flock) locks, and they are only released
+ * automatically when the last reference to the the open file against which
+ * they were acquired is put.
+ */
+#define F_GETLKP	36
+#define F_SETLKP	37
+#define F_SETLKPW	38
+
 #define F_OWNER_TID	0
 #define F_OWNER_PID	1
 #define F_OWNER_PGRP	2
@@ -186,8 +202,6 @@ struct flock {
 };
 #endif
 
-#ifndef CONFIG_64BIT
-
 #ifndef HAVE_ARCH_STRUCT_FLOCK64
 #ifndef __ARCH_FLOCK64_PAD
 #define __ARCH_FLOCK64_PAD
@@ -202,6 +216,5 @@ struct flock64 {
 	__ARCH_FLOCK64_PAD
 };
 #endif
-#endif /* !CONFIG_64BIT */
 
 #endif /* _ASM_GENERIC_FCNTL_H */