summaryrefslogtreecommitdiff
path: root/arch/tile/include/asm/page.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/tile/include/asm/page.h')
-rw-r--r--arch/tile/include/asm/page.h10
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/tile/include/asm/page.h b/arch/tile/include/asm/page.h
index 8eca6a0e1..498a5f712 100644
--- a/arch/tile/include/asm/page.h
+++ b/arch/tile/include/asm/page.h
@@ -321,6 +321,16 @@ static inline int pfn_valid(unsigned long pfn)
#define virt_to_page(kaddr) pfn_to_page(kaddr_to_pfn((void *)(kaddr)))
#define page_to_virt(page) pfn_to_kaddr(page_to_pfn(page))
+/*
+ * The kernel text is mapped at MEM_SV_START as read-only. To allow
+ * modifying kernel text, it is also mapped at PAGE_OFFSET as read-write.
+ * This macro converts a kernel address to its writable kernel text mapping,
+ * which is used to modify the text code on a running kernel by kgdb,
+ * ftrace, kprobe, jump label, etc.
+ */
+#define ktext_writable_addr(kaddr) \
+ ((unsigned long)(kaddr) - MEM_SV_START + PAGE_OFFSET)
+
struct mm_struct;
extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
extern pte_t *virt_to_kpte(unsigned long kaddr);