[PATCH] makedumpfile: Support _count -> _refcount rename in struct page

[Pratyush Anand]

Resolves: bz1342744

Upstream:
https://sourceforge.net/p/makedumpfile/code/ci/2c21d4656e8d3c2af2b1e14809...

Signed-off-by: Pratyush Anand <panand(a)redhat.com&gt;
---
 ...pport-_count-_refcount-rename-in-struct-p.patch | 108 +++++++++++++++++++++
 kexec-tools.spec                                   |   2 +
 2 files changed, 110 insertions(+)
 create mode 100644
kexec-tools-2.0.12-makedumpfile-Support-_count-_refcount-rename-in-struct-p.patch

diff --git
a/kexec-tools-2.0.12-makedumpfile-Support-_count-_refcount-rename-in-struct-p.patch
b/kexec-tools-2.0.12-makedumpfile-Support-_count-_refcount-rename-in-struct-p.patch
new file mode 100644
index 000000000000..479e234d04a1
--- /dev/null
+++ b/kexec-tools-2.0.12-makedumpfile-Support-_count-_refcount-rename-in-struct-p.patch
@@ -0,0 +1,108 @@
+From 2c21d4656e8d3c2af2b1e14809d076941ae69e96 Mon Sep 17 00:00:00 2001
+Message-Id:
<2c21d4656e8d3c2af2b1e14809d076941ae69e96.1468205827.git.panand(a)redhat.com&gt;
+From: Vitaly Kuznetsov <vkuznets(a)redhat.com&gt;
+Date: Fri, 17 Jun 2016 18:41:26 +0900
+Subject: [PATCH] [PATCH v2] Support _count -> _refcount rename in struct page
+
+_count member was renamed to _refcount in linux commit 0139aa7b7fa12
+("mm: rename _count, field of the struct page, to _refcount") and this
+broke makedumpfile. The reason for making the change was to find all users
+accessing it directly and not through the recommended API. I tried
+suggesting to revert the change but failed, I see no other choice than to
+start supporting both _count and _refcount in makedumpfile.
+
+Signed-off-by: Vitaly Kuznetsov <vkuznets(a)redhat.com&gt;
+---
+ makedumpfile-1.6.0/makedumpfile.c | 26 +++++++++++++++++++++-----
+ makedumpfile-1.6.0/makedumpfile.h |  3 ++-
+ 2 files changed, 23 insertions(+), 6 deletions(-)
+
+diff --git a/makedumpfile-1.6.0/makedumpfile.c b/makedumpfile-1.6.0/makedumpfile.c
+index 853b99951706..fd884d3796be 100644
+--- a/makedumpfile-1.6.0/makedumpfile.c
++++ b/makedumpfile-1.6.0/makedumpfile.c
+@@ -1579,7 +1579,14 @@ get_structure_info(void)
+ 	 */
+ 	SIZE_INIT(page, "page");
+ 	OFFSET_INIT(page.flags, "page", "flags");
+-	OFFSET_INIT(page._count, "page", "_count");
++	OFFSET_INIT(page._refcount, "page", "_refcount");
++	if (OFFSET(page._refcount) == NOT_FOUND_STRUCTURE) {
++		info->flag_use_count = TRUE;
++		OFFSET_INIT(page._refcount, "page", "_count");
++	} else {
++		info->flag_use_count = FALSE;
++	}
++
+ 	OFFSET_INIT(page.mapping, "page", "mapping");
+ 	OFFSET_INIT(page._mapcount, "page", "_mapcount");
+ 	OFFSET_INIT(page.private, "page", "private");
+@@ -2044,7 +2051,7 @@ get_mem_type(void)
+ 
+ 	if ((SIZE(page) == NOT_FOUND_STRUCTURE)
+ 	    || (OFFSET(page.flags) == NOT_FOUND_STRUCTURE)
+-	    || (OFFSET(page._count) == NOT_FOUND_STRUCTURE)
++	    || (OFFSET(page._refcount) == NOT_FOUND_STRUCTURE)
+ 	    || (OFFSET(page.mapping) == NOT_FOUND_STRUCTURE)) {
+ 		ret = NOT_FOUND_MEMTYPE;
+ 	} else if ((((SYMBOL(node_data) != NOT_FOUND_SYMBOL)
+@@ -2151,7 +2158,10 @@ write_vmcoreinfo_data(void)
+ 	 * write the member offset of 1st kernel
+ 	 */
+ 	WRITE_MEMBER_OFFSET("page.flags", page.flags);
+-	WRITE_MEMBER_OFFSET("page._count", page._count);
++	if (info->flag_use_count)
++		WRITE_MEMBER_OFFSET("page._count", page._refcount);
++	else
++		WRITE_MEMBER_OFFSET("page._refcount", page._refcount);
+ 	WRITE_MEMBER_OFFSET("page.mapping", page.mapping);
+ 	WRITE_MEMBER_OFFSET("page.lru", page.lru);
+ 	WRITE_MEMBER_OFFSET("page._mapcount", page._mapcount);
+@@ -2491,7 +2501,13 @@ read_vmcoreinfo(void)
+ 
+ 
+ 	READ_MEMBER_OFFSET("page.flags", page.flags);
+-	READ_MEMBER_OFFSET("page._count", page._count);
++	READ_MEMBER_OFFSET("page._refcount", page._refcount);
++	if (OFFSET(page._refcount) == NOT_FOUND_STRUCTURE) {
++		info->flag_use_count = TRUE;
++		READ_MEMBER_OFFSET("page._count", page._refcount);
++	} else {
++		info->flag_use_count = FALSE;
++	}
+ 	READ_MEMBER_OFFSET("page.mapping", page.mapping);
+ 	READ_MEMBER_OFFSET("page.lru", page.lru);
+ 	READ_MEMBER_OFFSET("page._mapcount", page._mapcount);
+@@ -5615,7 +5631,7 @@ __exclude_unnecessary_pages(unsigned long mem_map,
+ 		pcache  = page_cache + (index_pg * SIZE(page));
+ 
+ 		flags   = ULONG(pcache + OFFSET(page.flags));
+-		_count  = UINT(pcache + OFFSET(page._count));
++		_count  = UINT(pcache + OFFSET(page._refcount));
+ 		mapping = ULONG(pcache + OFFSET(page.mapping));
+ 
+ 		if (OFFSET(page.compound_order) != NOT_FOUND_STRUCTURE) {
+diff --git a/makedumpfile-1.6.0/makedumpfile.h b/makedumpfile-1.6.0/makedumpfile.h
+index 251d4bfac060..533e5b89f345 100644
+--- a/makedumpfile-1.6.0/makedumpfile.h
++++ b/makedumpfile-1.6.0/makedumpfile.h
+@@ -1100,6 +1100,7 @@ struct DumpInfo {
+ 	int		flag_nospace;	     /* the flag of "No space on device" error */
+ 	int		flag_vmemmap;        /* kernel supports vmemmap address space */
+ 	int		flag_excludevm;      /* -e - excluding unused vmemmap pages */
++	int		flag_use_count;      /* _refcount is named _count in struct page */
+ 	unsigned long	vaddr_for_vtop;      /* virtual address for debugging */
+ 	long		page_size;           /* size of page */
+ 	long		page_shift;
+@@ -1483,7 +1484,7 @@ struct size_table {
+ struct offset_table {
+ 	struct page {
+ 		long	flags;
+-		long	_count;
++		long	_refcount;
+ 		long	mapping;
+ 		long	lru;
+ 		long	_mapcount;
+-- 
+2.5.5
+
diff --git a/kexec-tools.spec b/kexec-tools.spec
index bca9df47507c..83295b1a7fb8 100644
--- a/kexec-tools.spec
+++ b/kexec-tools.spec
@@ -86,6 +86,7 @@ Patch503: kexec-tools-2.0.12-Properly-align-powerpc64-.toc.patch
 # Patches 601 onward are generic patches
 #
 Patch601: kexec-tools-2.0.3-disable-kexec-test.patch
+Patch602:
kexec-tools-2.0.12-makedumpfile-Support-_count-_refcount-rename-in-struct-p.patch
 
 %description
 kexec-tools provides /sbin/kexec binary that facilitates a new
@@ -113,6 +114,7 @@ tar -z -x -v -f %{SOURCE23}
 %patch502 -p1
 %patch503 -p1
 %patch601 -p1
+%patch602 -p1
 
 %ifarch ppc
 %define archdef ARCH=ppc
-- 
2.5.5