[PATCH 0/3] btrfs-progs: build on SLE11

[PATCH 0/3] btrfs-progs: build on SLE11

[jeffm]

From: Jeff Mahoney <jeffm@suse.com>

This patch set allows btrfs-progs to build without further patching
on a stock SLE11 SP4 install.  The major issues were:
- new dependencies on e2fsprogs 1.42
- use of -std=gnu90, which gcc 4.3.4 doesn't support
- use of m4_chomp, introduced in autoconf 2.64.

This patch set is also posted as a GitHub pull request:
https://github.com/kdave/btrfs-progs/pull/125

-Jeff

---

Jeff Mahoney (3):
  btrfs-progs: convert: fix support for e2fsprogs < 1.42
  btrfs-progs: build: detect whether -std=gnu90 is supported
  btrfs-progs: build: use m4_flatten instead of m4_chomp

 Makefile                    |  1 -
 Makefile.inc.in             |  1 +
 configure.ac                | 10 +++---
 convert/source-ext2.h       | 12 +++++++-
 m4/ax_check_compile_flag.m4 | 74 +++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 90 insertions(+), 8 deletions(-)
 create mode 100644 m4/ax_check_compile_flag.m4

-- 
2.12.3

[PATCH 1/3] btrfs-progs: convert: fix support for e2fsprogs < 1.42

[jeffm]

From: Jeff Mahoney <jeffm@suse.com>

Commit 324d4c1857a (btrfs-progs: convert: Add larger device support)
introduced new dependencies on the 64-bit API provided by e2fsprogs.
That API was introduced in v1.42 (along with bigalloc).

This patch maps the following to their equivalents in e2fsprogs < 1.42.
- ext2fs_get_block_bitmap_range2
- ext2fs_inode_data_blocks2
- ext2fs_read_ext_attr2

Since we need to detect and define EXT2_FLAG_64BITS for compatibilty
anyway, it makes sense to use that to detect the older e2fsprogs instead
of defining a new flag ourselves.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
---
 configure.ac          |  6 +-----
 convert/source-ext2.h | 12 +++++++++++-
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/configure.ac b/configure.ac
index af13a959..2dea1c64 100644
--- a/configure.ac
+++ b/configure.ac
@@ -140,11 +140,7 @@ BTRFSCONVERT_EXT2=0
 BTRFSCONVERT_REISERFS=0
 if test "x$enable_convert" = xyes; then
 	if test "x$with_convert" = "xauto" || echo "$with_convert" | grep -q "ext2"; then
-		PKG_CHECK_MODULES(EXT2FS, [ext2fs >= 1.42],,
-			[PKG_CHECK_MODULES(EXT2FS, [ext2fs],
-				[AC_DEFINE([HAVE_OLD_E2FSPROGS], [1],
-					  [E2fsprogs does not support BIGALLOC])]
-				)])
+		PKG_CHECK_MODULES(EXT2FS, [ext2fs])
 		PKG_CHECK_MODULES(COM_ERR, [com_err])
 		convertfs="${convertfs:+$convertfs,}ext2"
 		BTRFSCONVERT_EXT2=1
diff --git a/convert/source-ext2.h b/convert/source-ext2.h
index 80833b21..c3214125 100644
--- a/convert/source-ext2.h
+++ b/convert/source-ext2.h
@@ -33,8 +33,18 @@
  * BIGALLOC.
  * Unlike normal RO compat flag, BIGALLOC affects how e2fsprogs check used
  * space, and btrfs-convert heavily relies on it.
+ *
+ * e2fsprogs 1.42 also introduced the 64-bit API.  Any file system
+ * that requires it will have EXT4_FEATURE_INCOMPAT_64BIT set and
+ * will fail to open with earlier releases.  We can map it to the
+ * older API without risk of corruption.
  */
-#ifdef HAVE_OLD_E2FSPROGS
+#ifndef EXT2_FLAG_64BITS
+#define EXT2_FLAG_64BITS		(0)
+#define ext2fs_get_block_bitmap_range2 ext2fs_get_block_bitmap_range
+#define ext2fs_inode_data_blocks2 ext2fs_inode_data_blocks
+#define ext2fs_read_ext_attr2 ext2fs_read_ext_attr
+#define ext2fs_blocks_count(s)		((s)->s_blocks_count)
 #define EXT2FS_CLUSTER_RATIO(fs)	(1)
 #define EXT2_CLUSTERS_PER_GROUP(s)	(EXT2_BLOCKS_PER_GROUP(s))
 #define EXT2FS_B2C(fs, blk)		(blk)
-- 
2.12.3

[PATCH 2/3] btrfs-progs: build: detect whether -std=gnu90 is supported

[jeffm]

From: Jeff Mahoney <jeffm@suse.com>

Older versions of gcc don't support -std=gnu90 so btrfs-progs won't
build at all on older distros.  We can detect whether the compiler
supports -std=gnu90 and fall back to -std=gnu89 if it doesn't.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
---
 Makefile                    |  1 -
 Makefile.inc.in             |  1 +
 configure.ac                |  2 ++
 m4/ax_check_compile_flag.m4 | 74 +++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 77 insertions(+), 1 deletion(-)
 create mode 100644 m4/ax_check_compile_flag.m4

diff --git a/Makefile b/Makefile
index 5ba76d2e..c0eb3d68 100644
--- a/Makefile
+++ b/Makefile
@@ -63,7 +63,6 @@ ABSTOPDIR = $(shell pwd)
 TOPDIR := .
 
 # Common build flags
-CSTD = -std=gnu90
 CFLAGS = $(SUBST_CFLAGS) \
 	 $(CSTD) \
 	 -include config.h \
diff --git a/Makefile.inc.in b/Makefile.inc.in
index 52410f69..fc3dec69 100644
--- a/Makefile.inc.in
+++ b/Makefile.inc.in
@@ -4,6 +4,7 @@
 export
 
 CC = @CC@
+CSTD = @CSTD@
 LN_S = @LN_S@
 AR = @AR@
 RM = @RM@
diff --git a/configure.ac b/configure.ac
index 2dea1c64..17880206 100644
--- a/configure.ac
+++ b/configure.ac
@@ -30,6 +30,8 @@ AC_CANONICAL_HOST
 AC_C_CONST
 AC_C_VOLATILE
 AC_C_BIGENDIAN
+AX_CHECK_COMPILE_FLAG([-std=gnu90],[CSTD=-std=gnu90],[CSTD=-std=gnu89])
+AC_SUBST([CSTD])
 
 AC_SYS_LARGEFILE
 
diff --git a/m4/ax_check_compile_flag.m4 b/m4/ax_check_compile_flag.m4
new file mode 100644
index 00000000..dcabb92a
--- /dev/null
+++ b/m4/ax_check_compile_flag.m4
@@ -0,0 +1,74 @@
+# ===========================================================================
+#  https://www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_CHECK_COMPILE_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT])
+#
+# DESCRIPTION
+#
+#   Check whether the given FLAG works with the current language's compiler
+#   or gives an error.  (Warnings, however, are ignored)
+#
+#   ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
+#   success/failure.
+#
+#   If EXTRA-FLAGS is defined, it is added to the current language's default
+#   flags (e.g. CFLAGS) when the check is done.  The check is thus made with
+#   the flags: "CFLAGS EXTRA-FLAGS FLAG".  This can for example be used to
+#   force the compiler to issue an error when a bad flag is given.
+#
+#   INPUT gives an alternative input source to AC_COMPILE_IFELSE.
+#
+#   NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
+#   macro in sync with AX_CHECK_{PREPROC,LINK}_FLAG.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
+#   Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
+#
+#   This program is free software: you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by the
+#   Free Software Foundation, either version 3 of the License, or (at your
+#   option) any later version.
+#
+#   This program is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+#   Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License along
+#   with this program. If not, see <https://www.gnu.org/licenses/>.
+#
+#   As a special exception, the respective Autoconf Macro's copyright owner
+#   gives unlimited permission to copy, distribute and modify the configure
+#   scripts that are the output of Autoconf when processing the Macro. You
+#   need not follow the terms of the GNU General Public License when using
+#   or distributing such scripts, even though portions of the text of the
+#   Macro appear in them. The GNU General Public License (GPL) does govern
+#   all other use of the material that constitutes the Autoconf Macro.
+#
+#   This special exception to the GPL applies to versions of the Autoconf
+#   Macro released by the Autoconf Archive. When you make and distribute a
+#   modified version of the Autoconf Macro, you may extend this special
+#   exception to the GPL to apply to your modified version as well.
+
+#serial 5
+
+AC_DEFUN([AX_CHECK_COMPILE_FLAG],
+[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF
+AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl
+AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [
+  ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS
+  _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1"
+  AC_COMPILE_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])],
+    [AS_VAR_SET(CACHEVAR,[yes])],
+    [AS_VAR_SET(CACHEVAR,[no])])
+  _AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags])
+AS_VAR_IF(CACHEVAR,yes,
+  [m4_default([$2], :)],
+  [m4_default([$3], :)])
+AS_VAR_POPDEF([CACHEVAR])dnl
+])dnl AX_CHECK_COMPILE_FLAGS
-- 
2.12.3

[PATCH 3/3] btrfs-progs: build: use m4_flatten instead of m4_chomp

[jeffm]

From: Jeff Mahoney <jeffm@suse.com>

Commit 2e1932e6a38 (btrfs-progs: build: simplify version tracking)
started m4_chomp to strip the newlines from the version file.  m4_chomp
was introduced in autoconf 2.64 but SLE11 ships with autoconf 2.63.
For purposes of just stripping the newline, m4_flatten is sufficient.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
---
 configure.ac | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 17880206..a0cebf15 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,5 +1,5 @@
 AC_INIT([btrfs-progs],
-	m4_chomp(m4_include([VERSION])),
+	m4_flatten(m4_include([VERSION])),
 	[linux-btrfs@vger.kernel.org],,
 	[http://btrfs.wiki.kernel.org])
 
-- 
2.12.3

Re: [PATCH 3/3] btrfs-progs: build: use m4_flatten instead of m4_chomp

[Jeff Mahoney]

On 4/27/18 2:56 PM, jeffm@suse.com wrote:
> From: Jeff Mahoney <jeffm@suse.com>
> 
> Commit 2e1932e6a38 (btrfs-progs: build: simplify version tracking)
> started m4_chomp to strip the newlines from the version file.  m4_chomp
> was introduced in autoconf 2.64 but SLE11 ships with autoconf 2.63.
> For purposes of just stripping the newline, m4_flatten is sufficient.

Scratch that.  The previous patch also requires autoconf 2.64.

-Jeff

> Signed-off-by: Jeff Mahoney <jeffm@suse.com>
> ---
>  configure.ac | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/configure.ac b/configure.ac
> index 17880206..a0cebf15 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -1,5 +1,5 @@
>  AC_INIT([btrfs-progs],
> -	m4_chomp(m4_include([VERSION])),
> +	m4_flatten(m4_include([VERSION])),
>  	[linux-btrfs@vger.kernel.org],,
>  	[http://btrfs.wiki.kernel.org])
>  
> 


-- 
Jeff Mahoney
SUSE Labs

Re: [PATCH 3/3] btrfs-progs: build: use m4_flatten instead of m4_chomp

[David Sterba]

On Fri, Apr 27, 2018 at 03:18:17PM -0400, Jeff Mahoney wrote:
> On 4/27/18 2:56 PM, jeffm@suse.com wrote:
> > From: Jeff Mahoney <jeffm@suse.com>
> > 
> > Commit 2e1932e6a38 (btrfs-progs: build: simplify version tracking)
> > started m4_chomp to strip the newlines from the version file.  m4_chomp
> > was introduced in autoconf 2.64 but SLE11 ships with autoconf 2.63.
> > For purposes of just stripping the newline, m4_flatten is sufficient.
> 
> Scratch that.  The previous patch also requires autoconf 2.64.

I wanted to avoid shell tricks, but this should work everywhere:

m4_esyscmd([echo -n $(cat VERSION)])

Re: [PATCH 3/3] btrfs-progs: build: use m4_flatten instead of m4_chomp

[Jeff Mahoney]

[-- Attachment #1.1: Type: text/plain, Size: 1432 bytes --]

On 4/29/18 6:13 AM, David Sterba wrote:
> On Fri, Apr 27, 2018 at 03:18:17PM -0400, Jeff Mahoney wrote:
>> On 4/27/18 2:56 PM, jeffm@suse.com wrote:
>>> From: Jeff Mahoney <jeffm@suse.com>
>>>
>>> Commit 2e1932e6a38 (btrfs-progs: build: simplify version tracking)
>>> started m4_chomp to strip the newlines from the version file.  m4_chomp
>>> was introduced in autoconf 2.64 but SLE11 ships with autoconf 2.63.
>>> For purposes of just stripping the newline, m4_flatten is sufficient.
>>
>> Scratch that.  The previous patch also requires autoconf 2.64.
> 
> I wanted to avoid shell tricks, but this should work everywhere:
> 
> m4_esyscmd([echo -n $(cat VERSION)])
> 

m4_flatten should work everywhere.  It's the AX_CHECK_COMPILE_FLAGS that
depends on autoconf 2.64.

I can fix the dependency, but it ends up looking like:

m4_version_prereq([2.64], [
    AX_CHECK_COMPILE_FLAG([-std=gnu90],[CSTD=-std=gnu90],[CSTD=-std=gnu89])
  ], [
    AX_GCC_VERSION([4], [5], [0], [CSTD=-std=gnu90],[CSTD=-std=gnu89])
  ])
AC_SUBST([CSTD])

AX_GCC_VERSION is deprecated, but works with earlier autoconf versions.
I'm not thrilled about it, but keying off the autoconf version and using
the newer way for newer versions means it'll be easier to drop it later
when we drop support for earlier autoconf.

Alternatively, I can just put this patch in the OBS project.

-Jeff

-- 
Jeff Mahoney
SUSE Labs


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