Linux 2.6.39 compat, zlib_deflate_workspacesize()

The function zlib_deflate_workspacesize() now take 2 arguments.
This was done to avoid always having to allocate the maximum size
workspace (268K).  The caller can now specific the windowBits and
memLevel compression parameters to get a smaller workspace.

For our purposes we introduce a spl_zlib_deflate_workspacesize()
wrapper which accepts both arguments.  When the two argument
version of zlib_deflate_workspacesize() is available the arguments
are passed through.  When it's not we assume the worst case and
a maximally sized workspace is used.

config/spl-build.m4

@@ -80,6 +80,7 @@ AC_DEFUN([SPL_AC_CONFIG_KERNEL], [
 	SPL_AC_SHRINK_DCACHE_MEMORY
 	SPL_AC_SHRINK_ICACHE_MEMORY
 	SPL_AC_KERN_PATH_PARENT
+	SPL_AC_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE
 ])
 
 AC_DEFUN([SPL_AC_MODULE_SYMVERS], [
@@ -1802,3 +1803,25 @@ AC_DEFUN([SPL_AC_KERN_PATH_PARENT], [
 		[kern_path_parent() is available])],
 		[])
 ])
+
+dnl #
+dnl # 2.6.39 API compat,
+dnl # The function zlib_deflate_workspacesize() now take 2 arguments.
+dnl # This was done to avoid always having to allocate the maximum size
+dnl # workspace (268K).  The caller can now specific the windowBits and
+dnl # memLevel compression parameters to get a smaller workspace.
+dnl #
+AC_DEFUN([SPL_AC_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE],
+	[AC_MSG_CHECKING([whether zlib_deflate_workspacesize() wants 2 args])
+	SPL_LINUX_TRY_COMPILE([
+		#include <linux/zlib.h>
+	],[
+		return zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL);
+	],[
+		AC_MSG_RESULT(yes)
+		AC_DEFINE(HAVE_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE, 1,
+		          [zlib_deflate_workspacesize() wants 2 args])
+	],[
+		AC_MSG_RESULT(no)
+	])
+])

configure

@@ -15654,6 +15654,70 @@ _ACEOF
 	fi
 
 
+	{ $as_echo "$as_me:$LINENO: checking whether zlib_deflate_workspacesize() wants 2 args" >&5
+$as_echo_n "checking whether zlib_deflate_workspacesize() wants 2 args... " >&6; }
+
+
+cat confdefs.h - <<_ACEOF >conftest.c
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+
+		#include <linux/zlib.h>
+
+int
+main (void)
+{
+
+		return zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL);
+
+  ;
+  return 0;
+}
+
+_ACEOF
+
+
+	rm -Rf build && mkdir -p build
+	echo "obj-m := conftest.o" >build/Makefile
+	if { ac_try='cp conftest.c build && make modules -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } >/dev/null && { ac_try='test -s build/conftest.o'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+		{ $as_echo "$as_me:$LINENO: result: yes" >&5
+$as_echo "yes" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE 1
+_ACEOF
+
+
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+		{ $as_echo "$as_me:$LINENO: result: no" >&5
+$as_echo "no" >&6; }
+
+
+
+fi
+
+	rm -Rf build
+
+
+
  ;;
                 user)
 
@@ -19668,6 +19732,70 @@ _ACEOF
 	fi
 
 
+	{ $as_echo "$as_me:$LINENO: checking whether zlib_deflate_workspacesize() wants 2 args" >&5
+$as_echo_n "checking whether zlib_deflate_workspacesize() wants 2 args... " >&6; }
+
+
+cat confdefs.h - <<_ACEOF >conftest.c
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+
+		#include <linux/zlib.h>
+
+int
+main (void)
+{
+
+		return zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL);
+
+  ;
+  return 0;
+}
+
+_ACEOF
+
+
+	rm -Rf build && mkdir -p build
+	echo "obj-m := conftest.o" >build/Makefile
+	if { ac_try='cp conftest.c build && make modules -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } >/dev/null && { ac_try='test -s build/conftest.o'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+		{ $as_echo "$as_me:$LINENO: result: yes" >&5
+$as_echo "yes" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE 1
+_ACEOF
+
+
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+		{ $as_echo "$as_me:$LINENO: result: no" >&5
+$as_echo "no" >&6; }
+
+
+
+fi
+
+	rm -Rf build
+
+
+
 
 
 

include/linux/zlib_compat.h

@@ -0,0 +1,37 @@
+/*****************************************************************************\
+ *  Copyright (C) 2011 Lawrence Livermore National Security, LLC.
+ *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
+ *  Written by Brian Behlendorf <behlendorf1@llnl.gov>.
+ *  UCRL-CODE-235197
+ *
+ *  This file is part of the SPL, Solaris Porting Layer.
+ *  For details, see <http://github.com/behlendorf/spl/>.
+ *
+ *  The SPL 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 2 of the License, or (at your
+ *  option) any later version.
+ *
+ *  The SPL 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 the SPL.  If not, see <http://www.gnu.org/licenses/>.
+\*****************************************************************************/
+
+#ifndef _SPL_ZLIB_COMPAT_H
+#define _SPL_ZLIB_COMPAT_H
+
+#include <linux/zlib.h>
+
+#ifdef HAVE_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE
+#define spl_zlib_deflate_workspacesize(wb, ml) \
+	zlib_deflate_workspacesize(wb, ml)
+#else
+#define spl_zlib_deflate_workspacesize(wb, ml) \
+	zlib_deflate_workspacesize()
+#endif /* HAVE_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE */
+
+#endif /* SPL_ZLIB_COMPAT_H */

include/sys/types.h

@@ -41,6 +41,7 @@
 #include <linux/sysctl_compat.h>
 #include <linux/proc_compat.h>
 #include <linux/math64_compat.h>
+#include <linux/zlib_compat.h>
 
 #ifndef HAVE_UINTPTR_T
 typedef unsigned long			uintptr_t;

module/spl/spl-zlib.c

@@ -198,10 +198,14 @@ EXPORT_SYMBOL(z_uncompress);
 
 int zlib_init(void)
 {
+	int size;
         SENTRY;
+
+	size = MAX(spl_zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL),
+	    zlib_inflate_workspacesize());
+
 	zlib_workspace_cache = kmem_cache_create("spl_zlib_workspace_cache",
-	    max(zlib_deflate_workspacesize(), zlib_inflate_workspacesize()),
+	    size, 0, NULL, NULL, NULL, NULL, NULL, KMC_VMEM);
-	    0, NULL, NULL, NULL, NULL, NULL, KMC_VMEM);
         if (!zlib_workspace_cache)
 		SRETURN(1);
 

spl_config.h.in

@@ -21,6 +21,9 @@
 /* vfs_unlink() wants 2 args */
 #undef HAVE_2ARGS_VFS_UNLINK
 
+/* zlib_deflate_workspacesize() wants 2 args */
+#undef HAVE_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE
+
 /* file_fsync() wants 3 args */
 #undef HAVE_3ARGS_FILE_FSYNC