From 210501aa570fdaa8b06e56fd1c04f31f2d3f368b Mon Sep 17 00:00:00 2001
From: John David Anglin <dave@hiauly1.hia.nrc.ca>
Date: Sun, 11 Apr 2010 16:36:14 +0000
Subject: [PATCH] parisc: Call pagefault_disable/pagefault_enable in
kmap_atomic/kunmap_atomic
Based on the generic implementation of kmap_atomic and kunmap_atomic,
we should call pagefault_disable and pagefault_enable in our PA8000
implementation.
The define for kmap_atomic_prot was also missing, and I updated
kmap_atomic_pfn to use the generic implementation because of the
change to kmap_atomic.
I believe that this change is needed to fix the fork copy-on-write
bug.
Signed-off-by: John David Anglin <dave.anglin@nrc-cnrc.gc.ca>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
---
arch/parisc/include/asm/cacheflush.h | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/arch/parisc/include/asm/cacheflush.h b/arch/parisc/include/asm/cacheflush.h
index 477277739da5f8..4556d820128a43 100644
--- a/arch/parisc/include/asm/cacheflush.h
+++ b/arch/parisc/include/asm/cacheflush.h
@@ -2,6 +2,7 @@
#define _PARISC_CACHEFLUSH_H
#include <linux/mm.h>
+#include <linux/uaccess.h>
/* The usual comment is "Caches aren't brain-dead on the <architecture>".
* Unfortunately, that doesn't apply to PA-RISC. */
@@ -125,11 +126,20 @@ static inline void *kmap(struct page *page)
#define kunmap(page) kunmap_parisc(page_address(page))
-#define kmap_atomic(page, idx) page_address(page)
+static inline void *kmap_atomic(struct page *page, enum km_type idx)
+{
+ pagefault_disable();
+ return page_address(page);
+}
-#define kunmap_atomic(addr, idx) kunmap_parisc(addr)
+static inline void kunmap_atomic(void *addr, enum km_type idx)
+{
+ kunmap_parisc(addr);
+ pagefault_enable();
+}
-#define kmap_atomic_pfn(pfn, idx) page_address(pfn_to_page(pfn))
+#define kmap_atomic_prot(page, idx, prot) kmap_atomic(page, idx)
+#define kmap_atomic_pfn(pfn, idx) kmap_atomic(pfn_to_page(pfn), (idx))
#define kmap_atomic_to_page(ptr) virt_to_page(ptr)
#endif
--
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