Merge branch 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull read/write fix from Al Viro:
 "file_start_write()/file_end_write() got mixed into vfs_iter_write() by
  accident; that's a deadlock for all existing callers - they already do
  that, some - quite a bit outside.

  Easily fixed, fortunately"

* 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  move file_{start,end}_write() out of do_iter_write()

1 files changed, 4 insertions, 2 deletions

diff --git a/fs/read_write.c b/fs/read_write.c
index a2cbc8303dae..0cc7033aa413 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -925,12 +925,10 @@ static ssize_t do_iter_write(struct file *file, struct iov_iter *iter,
         if (ret < 0)
                 return ret;
 
-        file_start_write(file);
         if (file->f_op->write_iter)
                 ret = do_iter_readv_writev(file, iter, pos, WRITE, flags);
         else
                 ret = do_loop_readv_writev(file, iter, pos, WRITE, flags);
-        file_end_write(file);
         if (ret > 0)
                 fsnotify_modify(file);
         return ret;
@@ -973,7 +971,9 @@ ssize_t vfs_writev(struct file *file, const struct iovec __user *vec,
 
         ret = import_iovec(WRITE, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter);
         if (ret >= 0) {
+                file_start_write(file);
                 ret = do_iter_write(file, &iter, pos, flags);
+                file_end_write(file);
                 kfree(iov);
         }
         return ret;
@@ -1241,7 +1241,9 @@ static size_t compat_writev(struct file *file,
 
         ret = compat_import_iovec(WRITE, vec, vlen, UIO_FASTIOV, &iov, &iter);
         if (ret >= 0) {
+                file_start_write(file);
                 ret = do_iter_write(file, &iter, pos, flags);
+                file_end_write(file);
                 kfree(iov);
         }
         if (ret > 0)