Fix lookup_bdev() on Ubuntu

Ubuntu added support for checking inode permissions to lookup_bdev() in kernel
commit 193fb6a2c94fab8eb8ce70a5da4d21c7d4023bee (merged in 4.4.0-6.21).
Upstream bug: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1636517

This patch adds a test for Ubuntu's variant of lookup_bdev() to configure and
calls the function in the correct way.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Hajo Möller <dasjoe@gmail.com>
Closes #5336
This commit is contained in:
Hajo Möller 2016-10-26 19:30:43 +02:00 committed by Brian Behlendorf
parent 76a87a902e
commit e02aaf17f1
3 changed files with 31 additions and 10 deletions

View File

@ -1,17 +1,29 @@
dnl #
dnl # 2.6.27 API change
dnl # lookup_bdev() was exported.
dnl # 2.6.27, lookup_bdev() was exported.
dnl # 4.4.0-6.21 - x.y on Ubuntu, lookup_bdev() takes 2 arguments.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_LOOKUP_BDEV],
[AC_MSG_CHECKING([whether lookup_bdev() is available])
[AC_MSG_CHECKING([whether lookup_bdev() wants 1 arg])
ZFS_LINUX_TRY_COMPILE_SYMBOL([
#include <linux/fs.h>
], [
lookup_bdev(NULL);
], [lookup_bdev], [fs/block_dev.c], [
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_LOOKUP_BDEV, 1, [lookup_bdev() is available])
AC_DEFINE(HAVE_1ARG_LOOKUP_BDEV, 1, [lookup_bdev() wants 1 arg])
], [
AC_MSG_RESULT(no)
AC_MSG_CHECKING([whether lookup_bdev() wants 2 args])
ZFS_LINUX_TRY_COMPILE_SYMBOL([
#include <linux/fs.h>
], [
lookup_bdev(NULL, FMODE_READ);
], [lookup_bdev], [fs/block_dev.c], [
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_2ARGS_LOOKUP_BDEV, 1,
[lookup_bdev() wants 2 args])
], [
AC_MSG_RESULT(no)
])
])
])
])

View File

@ -263,12 +263,21 @@ bio_set_flags_failfast(struct block_device *bdev, int *flags)
/*
* 2.6.27 API change
* The function was exported for use, prior to this it existed by the
* The function was exported for use, prior to this it existed but the
* symbol was not exported.
*
* 4.4.0-6.21 API change for Ubuntu
* lookup_bdev() gained a second argument, FMODE_*, to check inode permissions.
*/
#ifndef HAVE_LOOKUP_BDEV
#define lookup_bdev(path) ERR_PTR(-ENOTSUP)
#endif
#ifdef HAVE_1ARG_LOOKUP_BDEV
#define vdev_lookup_bdev(path) lookup_bdev(path)
#else
#ifdef HAVE_2ARGS_LOOKUP_BDEV
#define vdev_lookup_bdev(path) lookup_bdev(path, 0)
#else
#define vdev_lookup_bdev(path) ERR_PTR(-ENOTSUP)
#endif /* HAVE_2ARGS_LOOKUP_BDEV */
#endif /* HAVE_1ARG_LOOKUP_BDEV */
/*
* 2.6.30 API change

View File

@ -174,7 +174,7 @@ zvol_is_zvol(const char *device)
struct block_device *bdev;
unsigned int major;
bdev = lookup_bdev(device);
bdev = vdev_lookup_bdev(device);
if (IS_ERR(bdev))
return (B_FALSE);