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 cbacf4faf447..4d69123377a2 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 60829565e552..23b2a35d712e 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;