parisc: Call pagefault_disable/pagefault_enable in kmap_atomic/kunmap_atomic (210501aa) · Commits · 戴 / test

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

+13 −3

Original line number	Diff line number	Diff line
		@@ -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

Admin message