Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs fixes from Al Viro.

Clean up file table accesses (get rid of fget_light() in favor of the
fdget() interface), add proper file position locking.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  get rid of fget_light()
  sockfd_lookup_light(): switch to fdget^W^Waway from fget_light
  vfs: atomic f_pos accesses as per POSIX
  ocfs2 syncs the wrong range...

2 files changed, 21 insertions, 14 deletions

diff --git a/include/linux/file.h b/include/linux/file.h
index cbacf4faf44..4d69123377a 100644
--- a/include/linux/file.h
+++ b/include/linux/file.h
@@ -28,33 +28,36 @@ static inline void fput_light(struct file *file, int fput_needed)
 
 struct fd {
 	struct file *file;
-	int need_put;
+	unsigned int flags;
 };
+#define FDPUT_FPUT       1
+#define FDPUT_POS_UNLOCK 2
 
 static inline void fdput(struct fd fd)
 {
-	if (fd.need_put)
+	if (fd.flags & FDPUT_FPUT)
 		fput(fd.file);
 }
 
 extern struct file *fget(unsigned int fd);
-extern struct file *fget_light(unsigned int fd, int *fput_needed);
+extern struct file *fget_raw(unsigned int fd);
+extern unsigned long __fdget(unsigned int fd);
+extern unsigned long __fdget_raw(unsigned int fd);
+extern unsigned long __fdget_pos(unsigned int fd);
 
-static inline struct fd fdget(unsigned int fd)
+static inline struct fd __to_fd(unsigned long v)
 {
-	int b;
-	struct file *f = fget_light(fd, &b);
-	return (struct fd){f,b};
+	return (struct fd){(struct file *)(v & ~3),v & 3};
 }
 
-extern struct file *fget_raw(unsigned int fd);
-extern struct file *fget_raw_light(unsigned int fd, int *fput_needed);
+static inline struct fd fdget(unsigned int fd)
+{
+	return __to_fd(__fdget(fd));
+}
 
 static inline struct fd fdget_raw(unsigned int fd)
 {
-	int b;
-	struct file *f = fget_raw_light(fd, &b);
-	return (struct fd){f,b};
+	return __to_fd(__fdget_raw(fd));
 }
 
 extern int f_dupfd(unsigned int from, struct file *file, unsigned flags);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 60829565e55..23b2a35d712 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -123,6 +123,9 @@ typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
 /* File is opened with O_PATH; almost nothing can be done with it */
 #define FMODE_PATH		((__force fmode_t)0x4000)
 
+/* File needs atomic accesses to f_pos */
+#define FMODE_ATOMIC_POS	((__force fmode_t)0x8000)
+
 /* File was opened by fanotify and shouldn't generate fanotify events */
 #define FMODE_NONOTIFY		((__force fmode_t)0x1000000)
 
@@ -780,13 +783,14 @@ struct file {
 	const struct file_operations	*f_op;
 
 	/*
-	 * Protects f_ep_links, f_flags, f_pos vs i_size in lseek SEEK_CUR.
+	 * Protects f_ep_links, f_flags.
 	 * Must not be taken from IRQ context.
 	 */
 	spinlock_t		f_lock;
 	atomic_long_t		f_count;
 	unsigned int 		f_flags;
 	fmode_t			f_mode;
+	struct mutex		f_pos_lock;
 	loff_t			f_pos;
 	struct fown_struct	f_owner;
 	const struct cred	*f_cred;
@@ -808,7 +812,7 @@ struct file {
 #ifdef CONFIG_DEBUG_WRITECOUNT
 	unsigned long f_mnt_write_state;
 #endif
-};
+} __attribute__((aligned(4)));	/* lest something weird decides that 2 is OK */
 
 struct file_handle {
 	__u32 handle_bytes;