HWPOISON: Turn ref argument into flags argument

Now that "ref" is just a boolean turn it into
a flags argument. First step is only a single flag
that makes the code's intention more clear, but more
may follow.

Signed-off-by: Andi Kleen <ak@linux.intel.com>

3 files changed, 8 insertions, 4 deletions

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 68c84bb2ad3f..135e19198cd3 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1331,8 +1331,11 @@ extern int account_locked_memory(struct mm_struct *mm, struct rlimit *rlim,
                                  size_t size);
 extern void refund_locked_memory(struct mm_struct *mm, size_t size);
 
+enum mf_flags {
+        MF_COUNT_INCREASED = 1 << 0,
+};
 extern void memory_failure(unsigned long pfn, int trapno);
-extern int __memory_failure(unsigned long pfn, int trapno, int ref);
+extern int __memory_failure(unsigned long pfn, int trapno, int flags);
 extern int sysctl_memory_failure_early_kill;
 extern int sysctl_memory_failure_recovery;
 extern void shake_page(struct page *p);
diff --git a/mm/madvise.c b/mm/madvise.c
index 18970aec0d2f..6ca34f0cd4aa 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -237,7 +237,7 @@ static int madvise_hwpoison(unsigned long start, unsigned long end)
                 printk(KERN_INFO "Injecting memory failure for page %lx at %lx\n",
                        page_to_pfn(p), start);
                 /* Ignore return value for now */
-                __memory_failure(page_to_pfn(p), 0, 1);
+                __memory_failure(page_to_pfn(p), 0, MF_COUNT_INCREASED);
         }
         return ret;
 }
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 4253e14fa709..3338c443272c 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -737,7 +737,7 @@ static void hwpoison_user_mappings(struct page *p, unsigned long pfn,
                       ret != SWAP_SUCCESS, pfn);
 }
 
-int __memory_failure(unsigned long pfn, int trapno, int ref)
+int __memory_failure(unsigned long pfn, int trapno, int flags)
 {
         unsigned long lru_flag;
         struct page_state *ps;
@@ -773,7 +773,8 @@ int __memory_failure(unsigned long pfn, int trapno, int ref)
          * In fact it's dangerous to directly bump up page count from 0,
          * that may make page_freeze_refs()/page_unfreeze_refs() mismatch.
          */
-        if (!ref && !get_page_unless_zero(compound_head(p))) {
+        if (!(flags & MF_COUNT_INCREASED) &&
+                !get_page_unless_zero(compound_head(p))) {
                 action_result(pfn, "free or high order kernel", IGNORED);
                 return PageBuddy(compound_head(p)) ? 0 : -EBUSY;
         }