preadv/pwritev: switch compat readv/preadv/writev/pwritev from fget to fget_light

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <linux-api@vger.kernel.org>
Cc: <linux-arch@vger.kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/compat.c

@@ -1222,13 +1222,14 @@ compat_sys_readv(unsigned long fd, const struct compat_iovec __user *vec,
 		 unsigned long vlen)
 {
 	struct file *file;
+	int fput_needed;
 	ssize_t ret;
 
-	file = fget(fd);
+	file = fget_light(fd, &fput_needed);
 	if (!file)
 		return -EBADF;
 	ret = compat_readv(file, vec, vlen, &file->f_pos);
-	fput(file);
+	fput_light(file, fput_needed);
 	return ret;
 }
 
@@ -1238,15 +1239,16 @@ compat_sys_preadv(unsigned long fd, const struct compat_iovec __user *vec,
 {
 	loff_t pos = ((loff_t)pos_high << 32) | pos_low;
 	struct file *file;
+	int fput_needed;
 	ssize_t ret;
 
 	if (pos < 0)
 		return -EINVAL;
-	file = fget(fd);
+	file = fget_light(fd, &fput_needed);
 	if (!file)
 		return -EBADF;
 	ret = compat_readv(file, vec, vlen, &pos);
-	fput(file);
+	fput_light(file, fput_needed);
 	return ret;
 }
 
@@ -1277,13 +1279,14 @@ compat_sys_writev(unsigned long fd, const struct compat_iovec __user *vec,
 		  unsigned long vlen)
 {
 	struct file *file;
+	int fput_needed;
 	ssize_t ret;
 
-	file = fget(fd);
+	file = fget_light(fd, &fput_needed);
 	if (!file)
 		return -EBADF;
 	ret = compat_writev(file, vec, vlen, &file->f_pos);
-	fput(file);
+	fput_light(file, fput_needed);
 	return ret;
 }
 
@@ -1293,15 +1296,16 @@ compat_sys_pwritev(unsigned long fd, const struct compat_iovec __user *vec,
 {
 	loff_t pos = ((loff_t)pos_high << 32) | pos_low;
 	struct file *file;
+	int fput_needed;
 	ssize_t ret;
 
 	if (pos < 0)
 		return -EINVAL;
-	file = fget(fd);
+	file = fget_light(fd, &fput_needed);
 	if (!file)
 		return -EBADF;
 	ret = compat_writev(file, vec, vlen, &pos);
-	fput(file);
+	fput_light(file, fput_needed);
 	return ret;
 }