s390/dasd: Establish DMA alignment

[linux-2.6-microblaze.git] / mm / page_alloc.c

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index e008a3d..b0bcab5 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2361,7 +2361,7 @@ static inline bool check_new_pcp(struct page *page, unsigned int order)
 }
 #endif /* CONFIG_DEBUG_VM */
 
-static inline bool should_skip_kasan_unpoison(gfp_t flags, bool init_tags)
+static inline bool should_skip_kasan_unpoison(gfp_t flags)
 {
        /* Don't skip if a software KASAN mode is enabled. */
        if (IS_ENABLED(CONFIG_KASAN_GENERIC) ||
@@ -2373,12 +2373,10 @@ static inline bool should_skip_kasan_unpoison(gfp_t flags, bool init_tags)
                return true;
 
        /*
-        * With hardware tag-based KASAN enabled, skip if either:
-        *
-        * 1. Memory tags have already been cleared via tag_clear_highpage().
-        * 2. Skipping has been requested via __GFP_SKIP_KASAN_UNPOISON.
+        * With hardware tag-based KASAN enabled, skip if this has been
+        * requested via __GFP_SKIP_KASAN_UNPOISON.
         */
-       return init_tags || (flags & __GFP_SKIP_KASAN_UNPOISON);
+       return flags & __GFP_SKIP_KASAN_UNPOISON;
 }
 
 static inline bool should_skip_init(gfp_t flags)
@@ -2397,6 +2395,7 @@ inline void post_alloc_hook(struct page *page, unsigned int order,
        bool init = !want_init_on_free() && want_init_on_alloc(gfp_flags) &&
                        !should_skip_init(gfp_flags);
        bool init_tags = init && (gfp_flags & __GFP_ZEROTAGS);
+       int i;
 
        set_page_private(page, 0);
        set_page_refcounted(page);
@@ -2422,8 +2421,6 @@ inline void post_alloc_hook(struct page *page, unsigned int order,
         * should be initialized as well).
         */
        if (init_tags) {
-               int i;
-
                /* Initialize both memory and tags. */
                for (i = 0; i != 1 << order; ++i)
                        tag_clear_highpage(page + i);
@@ -2431,13 +2428,17 @@ inline void post_alloc_hook(struct page *page, unsigned int order,
                /* Note that memory is already initialized by the loop above. */
                init = false;
        }
-       if (!should_skip_kasan_unpoison(gfp_flags, init_tags)) {
+       if (!should_skip_kasan_unpoison(gfp_flags)) {
                /* Unpoison shadow memory or set memory tags. */
                kasan_unpoison_pages(page, order, init);
 
                /* Note that memory is already initialized by KASAN. */
                if (kasan_has_integrated_init())
                        init = false;
+       } else {
+               /* Ensure page_address() dereferencing does not fault. */
+               for (i = 0; i != 1 << order; ++i)
+                       page_kasan_tag_reset(page + i);
        }
        /* If memory is still not initialized, do it now. */
        if (init)
@@ -3968,11 +3969,15 @@ static inline bool zone_watermark_fast(struct zone *z, unsigned int order,
         * need to be calculated.
         */
        if (!order) {
-               long fast_free;
+               long usable_free;
+               long reserved;
+
+               usable_free = free_pages;
+               reserved = __zone_watermark_unusable_free(z, 0, alloc_flags);
 
-               fast_free = free_pages;
-               fast_free -= __zone_watermark_unusable_free(z, 0, alloc_flags);
-               if (fast_free > mark + z->lowmem_reserve[highest_zoneidx])
+               /* reserved may over estimate high-atomic reserves. */
+               usable_free -= min(usable_free, reserved);
+               if (usable_free > mark + z->lowmem_reserve[highest_zoneidx])
                        return true;
        }