[PATCH] sparc32: make copy_to/from_user_page() usable from modular code

From: Paul Gortmaker
Date: Thu Feb 13 2014 - 16:15:23 EST


While copy_to/from_user_page() users are uncommon, there is one in
drivers/staging/lustre/lustre/libcfs/linux/linux-curproc.c which leads
to the following:

ERROR: "sparc32_cachetlb_ops" [drivers/staging/lustre/lustre/libcfs/libcfs.ko] undefined!

during routine allmodconfig build coverage. The reason this happens
is as follows:

In arch/sparc/include/asm/cacheflush_32.h we have:

#define flush_cache_page(vma,addr,pfn) \
sparc32_cachetlb_ops->cache_page(vma, addr)

#define copy_to_user_page(vma, page, vaddr, dst, src, len) \
do { \
flush_cache_page(vma, vaddr, page_to_pfn(page));\
memcpy(dst, src, len); \
} while (0)
#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
do { \
flush_cache_page(vma, vaddr, page_to_pfn(page));\
memcpy(dst, src, len); \
} while (0)

However, sparc32_cachetlb_ops isn't exported and hence the error.

Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
---
arch/sparc/mm/srmmu.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c
index 869023abe5a4..cfbe53c17b0d 100644
--- a/arch/sparc/mm/srmmu.c
+++ b/arch/sparc/mm/srmmu.c
@@ -14,6 +14,7 @@
#include <linux/pagemap.h>
#include <linux/vmalloc.h>
#include <linux/kdebug.h>
+#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/log2.h>
@@ -62,6 +63,7 @@ extern unsigned long last_valid_pfn;
static pgd_t *srmmu_swapper_pg_dir;

const struct sparc32_cachetlb_ops *sparc32_cachetlb_ops;
+EXPORT_SYMBOL(sparc32_cachetlb_ops);

#ifdef CONFIG_SMP
const struct sparc32_cachetlb_ops *local_ops;
--
1.8.5.2

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