SLES10 Fixes (part 6)

- Prior to 2.6.17 there were no *_pgdat helper functions in mm/mmzone.c. Instead for_each_zone() operated directly on pgdat_list which may or may not have been exported depending on how your kernel was compiled. Now new configure checks determine if you have the helpers or not, and if the needed symbols are exported. If they are not exported then they are dynamically aquired at runtime by kallsyms_lookup_name().
2024-11-17 01:51:00 +03:00 · 2009-05-20 14:23:13 -07:00 · 2009-05-20 14:23:13 -07:00 · 5232d256b4
commit 5232d256b4
parent 3731931529
6 changed files with 157 additions and 23 deletions
--- a/config/spl-build.m4
+++ b/config/spl-build.m4
@ -802,6 +802,31 @@ AC_DEFUN([SPL_AC_GET_VMALLOC_INFO], [
 		[])
 ])

+dnl #
+dnl # 2.6.17 API change
+dnl # The helper functions first_online_pgdat(), next_online_pgdat(), and
+dnl # next_zone() are introduced to simplify for_each_zone().  These symbols
+dnl # were exported in 2.6.17 for use by modules which was consistent with
+dnl # the previous implementation of for_each_zone().  From 2.6.18 - 2.6.19
+dnl # the symbols were exported as 'unused', and by 2.6.20 they exports
+dnl # were dropped entirely leaving modules no way to directly iterate over
+dnl # the zone list.  Because we need access to the zone helpers we check
+dnl # if the kernel contains the old or new implementation.  Then we check
+dnl # to see if the symbols we need for each version are available.  If they
+dnl # are not, dynamically aquire the addresses with kallsyms_lookup_name().
+dnl #
+AC_DEFUN([SPL_AC_PGDAT_HELPERS], [
+	AC_MSG_CHECKING([whether symbol *_pgdat exist])
+	grep -q -E 'first_online_pgdat' $LINUX/include/linux/mmzone.h 2>/dev/null
+	rc=$?
+	if test $rc -eq 0; then
+		AC_MSG_RESULT([yes])
+                AC_DEFINE(HAVE_PGDAT_HELPERS, 1, [pgdat helpers are available])
+	else
+		AC_MSG_RESULT([no])
+	fi
+])
+
 dnl #
 dnl # Proposed API change,
 dnl # This symbol is not available in stock kernels.  You may build a
@ -850,6 +875,19 @@ AC_DEFUN([SPL_AC_NEXT_ZONE], [
 		[])
 ])

+dnl #
+dnl # 2.6.17 API change,
+dnl # See SPL_AC_PGDAT_HELPERS for details.
+dnl #
+AC_DEFUN([SPL_AC_PGDAT_LIST], [
+	SPL_CHECK_SYMBOL_EXPORT(
+		[pgdat_list],
+		[],
+		[AC_DEFINE(HAVE_PGDAT_LIST, 1,
+		[pgdat_list is available])],
+		[])
+])
+
 dnl #
 dnl # Proposed API change,
 dnl # This symbol is not available in stock kernels.  You may build a
--- a/57
+++ b/57
@ -20798,6 +20798,24 @@ _ACEOF



+	echo "$as_me:$LINENO: checking whether symbol *_pgdat exist" >&5
+echo $ECHO_N "checking whether symbol *_pgdat exist... $ECHO_C" >&6
+	grep -q -E 'first_online_pgdat' $LINUX/include/linux/mmzone.h 2>/dev/null
+	rc=$?
+	if test $rc -eq 0; then
+		echo "$as_me:$LINENO: result: yes" >&5
+echo "${ECHO_T}yes" >&6
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_PGDAT_HELPERS 1
+_ACEOF
+
+	else
+		echo "$as_me:$LINENO: result: no" >&5
+echo "${ECHO_T}no" >&6
+	fi
+
+
 	echo "$as_me:$LINENO: checking whether symbol first_online_pgdat is exported" >&5
 echo $ECHO_N "checking whether symbol first_online_pgdat is exported... $ECHO_C" >&6
 	grep -q -E '[[:space:]]first_online_pgdat[[:space:]]' $LINUX_OBJ/Module.symvers 2>/dev/null
@ -20915,6 +20933,45 @@ _ACEOF



+	echo "$as_me:$LINENO: checking whether symbol pgdat_list is exported" >&5
+echo $ECHO_N "checking whether symbol pgdat_list is exported... $ECHO_C" >&6
+	grep -q -E '[[:space:]]pgdat_list[[:space:]]' $LINUX_OBJ/Module.symvers 2>/dev/null
+	rc=$?
+	if test $rc -ne 0; then
+		export=0
+		for file in ; do
+			grep -q -E "EXPORT_SYMBOL.*(pgdat_list)" "$LINUX_OBJ/$file" 2>/dev/null
+			rc=$?
+		        if test $rc -eq 0; then
+		                export=1
+		                break;
+		        fi
+		done
+		if test $export -eq 0; then
+			echo "$as_me:$LINENO: result: no" >&5
+echo "${ECHO_T}no" >&6
+
+		else
+			echo "$as_me:$LINENO: result: yes" >&5
+echo "${ECHO_T}yes" >&6
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_PGDAT_LIST 1
+_ACEOF
+
+		fi
+	else
+		echo "$as_me:$LINENO: result: yes" >&5
+echo "${ECHO_T}yes" >&6
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_PGDAT_LIST 1
+_ACEOF
+
+	fi
+
+
+
 	echo "$as_me:$LINENO: checking whether symbol get_zone_counts is exported" >&5
 echo $ECHO_N "checking whether symbol get_zone_counts is exported... $ECHO_C" >&6
 	grep -q -E '[[:space:]]get_zone_counts[[:space:]]' $LINUX_OBJ/Module.symvers 2>/dev/null
--- a/configure.ac
+++ b/configure.ac
@ -73,9 +73,11 @@ SPL_AC_DIV64_U64
 SPL_AC_3ARGS_ON_EACH_CPU
 SPL_AC_KALLSYMS_LOOKUP_NAME
 SPL_AC_GET_VMALLOC_INFO
+SPL_AC_PGDAT_HELPERS
 SPL_AC_FIRST_ONLINE_PGDAT
 SPL_AC_NEXT_ONLINE_PGDAT
 SPL_AC_NEXT_ZONE
+SPL_AC_PGDAT_LIST
 SPL_AC_GET_ZONE_COUNTS
 SPL_AC_GLOBAL_PAGE_STATE
 SPL_AC_ZONE_STAT_ITEM_FIA
--- a/include/sys/vmsystm.h
+++ b/include/sys/vmsystm.h
@ -93,26 +93,34 @@ extern get_vmalloc_info_t get_vmalloc_info_fn;
 #endif /* CONFIG_MMU */
 #endif /* HAVE_GET_VMALLOC_INFO */

+#ifdef HAVE_PGDAT_HELPERS
 /* Source linux/mm/mmzone.c */
-#ifndef HAVE_FIRST_ONLINE_PGDAT
+# ifndef HAVE_FIRST_ONLINE_PGDAT
 typedef struct pglist_data *(*first_online_pgdat_t)(void);
 extern first_online_pgdat_t first_online_pgdat_fn;
-#define first_online_pgdat()	first_online_pgdat_fn()
-#endif /* HAVE_FIRST_ONLINE_PGDAT */
+# define first_online_pgdat()	first_online_pgdat_fn()
+# endif /* HAVE_FIRST_ONLINE_PGDAT */

-/* Source linux/mm/mmzone.c */
-#ifndef HAVE_NEXT_ONLINE_PGDAT
+# ifndef HAVE_NEXT_ONLINE_PGDAT
 typedef struct pglist_data *(*next_online_pgdat_t)(struct pglist_data *);
 extern next_online_pgdat_t next_online_pgdat_fn;
-#define next_online_pgdat(pgd)	next_online_pgdat_fn(pgd)
-#endif /* HAVE_NEXT_ONLINE_PGDAT */
+# define next_online_pgdat(pgd)	next_online_pgdat_fn(pgd)
+# endif /* HAVE_NEXT_ONLINE_PGDAT */

-/* Source linux/mm/mmzone.c */
-#ifndef HAVE_NEXT_ZONE
+# ifndef HAVE_NEXT_ZONE
 typedef struct zone *(*next_zone_t)(struct zone *);
 extern next_zone_t next_zone_fn;
-#define next_zone(zone)		next_zone_fn(zone)
-#endif /* HAVE_NEXT_ZONE */
+# define next_zone(zone)	next_zone_fn(zone)
+# endif /* HAVE_NEXT_ZONE */
+
+#else /* HAVE_PGDAT_HELPERS */
+
+# ifndef HAVE_PGDAT_LIST
+extern struct pglist_data *pgdat_list_addr;
+# define pgdat_list		pgdat_list_addr
+# endif /* HAVE_PGDAT_LIST */
+
+#endif /* HAVE_PGDAT_HELPERS */

 /* Source linux/mm/vmstat.c */
 #ifndef HAVE_ZONE_STAT_ITEM_FIA
--- a/module/spl/spl-kmem.c
+++ b/module/spl/spl-kmem.c
@ -84,20 +84,30 @@ get_vmalloc_info_t get_vmalloc_info_fn = SYMBOL_POISON;
 EXPORT_SYMBOL(get_vmalloc_info_fn);
 #endif /* HAVE_GET_VMALLOC_INFO */

-#ifndef HAVE_FIRST_ONLINE_PGDAT
+#ifdef HAVE_PGDAT_HELPERS
+# ifndef HAVE_FIRST_ONLINE_PGDAT
 first_online_pgdat_t first_online_pgdat_fn = SYMBOL_POISON;
 EXPORT_SYMBOL(first_online_pgdat_fn);
-#endif /* HAVE_FIRST_ONLINE_PGDAT */
+# endif /* HAVE_FIRST_ONLINE_PGDAT */

-#ifndef HAVE_NEXT_ONLINE_PGDAT
+# ifndef HAVE_NEXT_ONLINE_PGDAT
 next_online_pgdat_t next_online_pgdat_fn = SYMBOL_POISON;
 EXPORT_SYMBOL(next_online_pgdat_fn);
-#endif /* HAVE_NEXT_ONLINE_PGDAT */
+# endif /* HAVE_NEXT_ONLINE_PGDAT */

-#ifndef HAVE_NEXT_ZONE
+# ifndef HAVE_NEXT_ZONE
 next_zone_t next_zone_fn = SYMBOL_POISON;
 EXPORT_SYMBOL(next_zone_fn);
-#endif /* HAVE_NEXT_ZONE */
+# endif /* HAVE_NEXT_ZONE */
+
+#else /* HAVE_PGDAT_HELPERS */
+
+# ifndef HAVE_PGDAT_LIST
+struct pglist_data *pgdat_list_addr = SYMBOL_POISON;
+EXPORT_SYMBOL(pgdat_list_addr);
+# endif /* HAVE_PGDAT_LIST */
+
+#endif /* HAVE_PGDAT_HELPERS */

 #ifndef HAVE_ZONE_STAT_ITEM_FIA
 # ifndef HAVE_GET_ZONE_COUNTS
@ -1806,32 +1816,45 @@ spl_kmem_init_kallsyms_lookup(void)
 	}
 #endif /* HAVE_GET_VMALLOC_INFO */

-#ifndef HAVE_FIRST_ONLINE_PGDAT
+#ifdef HAVE_PGDAT_HELPERS
+# ifndef HAVE_FIRST_ONLINE_PGDAT
 	first_online_pgdat_fn = (first_online_pgdat_t)
 		spl_kallsyms_lookup_name("first_online_pgdat");
 	if (!first_online_pgdat_fn) {
 		printk(KERN_ERR "Error: Unknown symbol first_online_pgdat\n");
 		return -EFAULT;
 	}
-#endif /* HAVE_FIRST_ONLINE_PGDAT */
+# endif /* HAVE_FIRST_ONLINE_PGDAT */

-#ifndef HAVE_NEXT_ONLINE_PGDAT
+# ifndef HAVE_NEXT_ONLINE_PGDAT
 	next_online_pgdat_fn = (next_online_pgdat_t)
 		spl_kallsyms_lookup_name("next_online_pgdat");
 	if (!next_online_pgdat_fn) {
 		printk(KERN_ERR "Error: Unknown symbol next_online_pgdat\n");
 		return -EFAULT;
 	}
-#endif /* HAVE_NEXT_ONLINE_PGDAT */
+# endif /* HAVE_NEXT_ONLINE_PGDAT */

-#ifndef HAVE_NEXT_ZONE
+# ifndef HAVE_NEXT_ZONE
 	next_zone_fn = (next_zone_t)
 		spl_kallsyms_lookup_name("next_zone");
 	if (!next_zone_fn) {
 		printk(KERN_ERR "Error: Unknown symbol next_zone\n");
 		return -EFAULT;
 	}
-#endif /* HAVE_NEXT_ZONE */
+# endif /* HAVE_NEXT_ZONE */
+
+#else /* HAVE_PGDAT_HELPERS */
+
+# ifndef HAVE_PGDAT_LIST
+	pgdat_list_addr = (struct pglist_data *)
+		spl_kallsyms_lookup_name("pgdat_list");
+	if (!pgdat_list_addr) {
+		printk(KERN_ERR "Error: Unknown symbol pgdat_list\n");
+		return -EFAULT;
+	}
+# endif /* HAVE_PGDAT_LIST */
+#endif /* HAVE_PGDAT_HELPERS */

 #ifndef HAVE_ZONE_STAT_ITEM_FIA
 # ifndef HAVE_GET_ZONE_COUNTS
--- a/spl_config.h.in
+++ b/spl_config.h.in
@ -105,6 +105,12 @@
 /* struct path used in struct nameidata */
 #undef HAVE_PATH_IN_NAMEIDATA

+/* pgdat helpers are available */
+#undef HAVE_PGDAT_HELPERS
+
+/* pgdat_list is available */
+#undef HAVE_PGDAT_LIST
+
 /* set_normalized_timespec() is available as export */
 #undef HAVE_SET_NORMALIZED_TIMESPEC_EXPORT