summaryrefslogtreecommitdiff
path: root/arch/tile/include/asm/page.h
diff options
context:
space:
mode:
authorDavid S. Miller <davem@davemloft.net>2016-02-01 18:44:07 -0800
committerDavid S. Miller <davem@davemloft.net>2016-02-01 18:44:07 -0800
commitb45efa30a626e915192a6c548cd8642379cd47cc (patch)
tree90d8b43ebceb850b0e7852d75283aebbd2abbc00 /arch/tile/include/asm/page.h
parent7a26019fdecdb45ff784ae4e3b7e0cc9045100ca (diff)
parent34229b277480f46c1e9a19f027f30b074512e68b (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
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 8eca6a0e1762..498a5f71245d 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);