zfs-fix-zpool-import-bug-with-nested-pools.patch

   1 From e02aaf17f15ad274fa1f24c9c826f1477911ea3f Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Hajo=20M=C3=B6ller?= <dasjoe@users.noreply.github.com>
   3 Date: Wed, 26 Oct 2016 19:30:43 +0200
   4 Subject: [PATCH] Fix lookup_bdev() on Ubuntu
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 Ubuntu added support for checking inode permissions to lookup_bdev() in kernel
  10 commit 193fb6a2c94fab8eb8ce70a5da4d21c7d4023bee (merged in 4.4.0-6.21).
  11 Upstream bug: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1636517
  12
  13 This patch adds a test for Ubuntu's variant of lookup_bdev() to configure and
  14 calls the function in the correct way.
  15
  16 Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
  17 Signed-off-by: Hajo Möller <dasjoe@gmail.com>
  18 Closes #5336
  19 ---
  20  config/kernel-lookup-bdev.m4  | 22 +++++++++++++++++-----
  21  include/linux/blkdev_compat.h | 17 +++++++++++++----
  22  module/zfs/zvol.c             |  2 +-
  23  3 files changed, 31 insertions(+), 10 deletions(-)
  24
  25 diff --git a/config/kernel-lookup-bdev.m4 b/config/kernel-lookup-bdev.m4
  26 index 245f95f..abbf55d 100644
  27 --- a/config/kernel-lookup-bdev.m4
  28 +++ b/config/kernel-lookup-bdev.m4
  29 @@ -1,17 +1,29 @@
  30  dnl #
  31 -dnl # 2.6.27 API change
  32 -dnl # lookup_bdev() was exported.
  33 +dnl # 2.6.27, lookup_bdev() was exported.
  34 +dnl # 4.4.0-6.21 - x.y on Ubuntu, lookup_bdev() takes 2 arguments.
  35  dnl #
  36  AC_DEFUN([ZFS_AC_KERNEL_LOOKUP_BDEV],
  37 -       [AC_MSG_CHECKING([whether lookup_bdev() is available])
  38 +       [AC_MSG_CHECKING([whether lookup_bdev() wants 1 arg])
  39         ZFS_LINUX_TRY_COMPILE_SYMBOL([
  40                 #include <linux/fs.h>
  41         ], [
  42                 lookup_bdev(NULL);
  43         ], [lookup_bdev], [fs/block_dev.c], [
  44                 AC_MSG_RESULT(yes)
  45 -               AC_DEFINE(HAVE_LOOKUP_BDEV, 1, [lookup_bdev() is available])
  46 +               AC_DEFINE(HAVE_1ARG_LOOKUP_BDEV, 1, [lookup_bdev() wants 1 arg])
  47         ], [
  48                 AC_MSG_RESULT(no)
  49 +               AC_MSG_CHECKING([whether lookup_bdev() wants 2 args])
  50 +               ZFS_LINUX_TRY_COMPILE_SYMBOL([
  51 +                       #include <linux/fs.h>
  52 +               ], [
  53 +                       lookup_bdev(NULL, FMODE_READ);
  54 +               ], [lookup_bdev], [fs/block_dev.c], [
  55 +                       AC_MSG_RESULT(yes)
  56 +                       AC_DEFINE(HAVE_2ARGS_LOOKUP_BDEV, 1,
  57 +                           [lookup_bdev() wants 2 args])
  58 +               ], [
  59 +                       AC_MSG_RESULT(no)
  60 +               ])
  61         ])
  62 -])
  63 +])
  64 \ No newline at end of file
  65 diff --git a/include/linux/blkdev_compat.h b/include/linux/blkdev_compat.h
  66 index bff93ff..1f90b98 100644
  67 --- a/include/linux/blkdev_compat.h
  68 +++ b/include/linux/blkdev_compat.h
  69 @@ -263,12 +263,21 @@ bio_set_flags_failfast(struct block_device *bdev, int *flags)
  70
  71  /*
  72   * 2.6.27 API change
  73 - * The function was exported for use, prior to this it existed by the
  74 + * The function was exported for use, prior to this it existed but the
  75   * symbol was not exported.
  76 + *
  77 + * 4.4.0-6.21 API change for Ubuntu
  78 + * lookup_bdev() gained a second argument, FMODE_*, to check inode permissions.
  79   */
  80 -#ifndef HAVE_LOOKUP_BDEV
  81 -#define        lookup_bdev(path)               ERR_PTR(-ENOTSUP)
  82 -#endif
  83 +#ifdef HAVE_1ARG_LOOKUP_BDEV
  84 +#define        vdev_lookup_bdev(path)  lookup_bdev(path)
  85 +#else
  86 +#ifdef HAVE_2ARGS_LOOKUP_BDEV
  87 +#define        vdev_lookup_bdev(path)  lookup_bdev(path, 0)
  88 +#else
  89 +#define        vdev_lookup_bdev(path)  ERR_PTR(-ENOTSUP)
  90 +#endif /* HAVE_2ARGS_LOOKUP_BDEV */
  91 +#endif /* HAVE_1ARG_LOOKUP_BDEV */
  92
  93  /*
  94   * 2.6.30 API change
  95 diff --git a/module/zfs/zvol.c b/module/zfs/zvol.c
  96 index bf6d59f..72a6bc5 100644
  97 --- a/module/zfs/zvol.c
  98 +++ b/module/zfs/zvol.c
  99 @@ -174,7 +174,7 @@ zvol_is_zvol(const char *device)
 100         struct block_device *bdev;
 101         unsigned int major;
 102
 103 -       bdev = lookup_bdev(device);
 104 +       bdev = vdev_lookup_bdev(device);
 105         if (IS_ERR(bdev))
 106                 return (B_FALSE);
 107