diff options
Diffstat (limited to 'arch/s390/include/asm/page.h')
-rw-r--r-- | arch/s390/include/asm/page.h | 56 |
1 files changed, 50 insertions, 6 deletions
diff --git a/arch/s390/include/asm/page.h b/arch/s390/include/asm/page.h index 3c987e9ec8d6..81ee2776088d 100644 --- a/arch/s390/include/asm/page.h +++ b/arch/s390/include/asm/page.h @@ -107,8 +107,8 @@ typedef pte_t *pgtable_t; #define __pgd(x) ((pgd_t) { (x) } ) #define __pgprot(x) ((pgprot_t) { (x) } ) -static inline void -page_set_storage_key(unsigned long addr, unsigned int skey, int mapped) +static inline void page_set_storage_key(unsigned long addr, + unsigned char skey, int mapped) { if (!mapped) asm volatile(".insn rrf,0xb22b0000,%0,%1,8,0" @@ -117,15 +117,59 @@ page_set_storage_key(unsigned long addr, unsigned int skey, int mapped) asm volatile("sske %0,%1" : : "d" (skey), "a" (addr)); } -static inline unsigned int -page_get_storage_key(unsigned long addr) +static inline unsigned char page_get_storage_key(unsigned long addr) { - unsigned int skey; + unsigned char skey; - asm volatile("iske %0,%1" : "=d" (skey) : "a" (addr), "0" (0)); + asm volatile("iske %0,%1" : "=d" (skey) : "a" (addr)); return skey; } +static inline int page_reset_referenced(unsigned long addr) +{ + unsigned int ipm; + + asm volatile( + " rrbe 0,%1\n" + " ipm %0\n" + : "=d" (ipm) : "a" (addr) : "cc"); + return !!(ipm & 0x20000000); +} + +/* Bits int the storage key */ +#define _PAGE_CHANGED 0x02 /* HW changed bit */ +#define _PAGE_REFERENCED 0x04 /* HW referenced bit */ +#define _PAGE_FP_BIT 0x08 /* HW fetch protection bit */ +#define _PAGE_ACC_BITS 0xf0 /* HW access control bits */ + +/* + * Test and clear dirty bit in storage key. + * We can't clear the changed bit atomically. This is a potential + * race against modification of the referenced bit. This function + * should therefore only be called if it is not mapped in any + * address space. + */ +#define __HAVE_ARCH_PAGE_TEST_AND_CLEAR_DIRTY +static inline int page_test_and_clear_dirty(unsigned long pfn, int mapped) +{ + unsigned char skey; + + skey = page_get_storage_key(pfn << PAGE_SHIFT); + if (!(skey & _PAGE_CHANGED)) + return 0; + page_set_storage_key(pfn << PAGE_SHIFT, skey & ~_PAGE_CHANGED, mapped); + return 1; +} + +/* + * Test and clear referenced bit in storage key. + */ +#define __HAVE_ARCH_PAGE_TEST_AND_CLEAR_YOUNG +static inline int page_test_and_clear_young(unsigned long pfn) +{ + return page_reset_referenced(pfn << PAGE_SHIFT); +} + struct page; void arch_free_page(struct page *page, int order); void arch_alloc_page(struct page *page, int order); |