1 files changed, 78 insertions, 2 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index d205c4be7f5b..7632c87da2c9 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -462,6 +462,7 @@ struct sk_buff {
 #ifdef CONFIG_IPV6_NDISC_NODETYPE
         __u8                    ndisc_nodetype:2;
 #endif
+        __u8                    pfmemalloc:1;
         __u8                    ooo_okay:1;
         __u8                    l4_rxhash:1;
         __u8                    wifi_acked_valid:1;
@@ -502,6 +503,15 @@ struct sk_buff {
 #include <linux/slab.h>
 
 
+#define SKB_ALLOC_FCLONE        0x01
+#define SKB_ALLOC_RX            0x02
+
+/* Returns true if the skb was allocated from PFMEMALLOC reserves */
+static inline bool skb_pfmemalloc(const struct sk_buff *skb)
+{
+        return unlikely(skb->pfmemalloc);
+}
+
 /*
  * skb might have a dst pointer attached, refcounted or not.
  * _skb_refdst low order bit is set if refcount was _not_ taken
@@ -565,7 +575,7 @@ extern bool skb_try_coalesce(struct sk_buff *to, struct sk_buff *from,
                              bool *fragstolen, int *delta_truesize);
 
 extern struct sk_buff *__alloc_skb(unsigned int size,
-                                   gfp_t priority, int fclone, int node);
+                                   gfp_t priority, int flags, int node);
 extern struct sk_buff *build_skb(void *data, unsigned int frag_size);
 static inline struct sk_buff *alloc_skb(unsigned int size,
                                         gfp_t priority)
@@ -576,7 +586,7 @@ static inline struct sk_buff *alloc_skb(unsigned int size,
 static inline struct sk_buff *alloc_skb_fclone(unsigned int size,
                                                gfp_t priority)
 {
-        return __alloc_skb(size, priority, 1, NUMA_NO_NODE);
+        return __alloc_skb(size, priority, SKB_ALLOC_FCLONE, NUMA_NO_NODE);
 }
 
 extern void skb_recycle(struct sk_buff *skb);
@@ -1237,6 +1247,17 @@ static inline void __skb_fill_page_desc(struct sk_buff *skb, int i,
 {
         skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
 
+        /*
+         * Propagate page->pfmemalloc to the skb if we can. The problem is
+         * that not all callers have unique ownership of the page. If
+         * pfmemalloc is set, we check the mapping as a mapping implies
+         * page->index is set (index and pfmemalloc share space).
+         * If it's a valid mapping, we cannot use page->pfmemalloc but we
+         * do not lose pfmemalloc information as the pages would not be
+         * allocated using __GFP_MEMALLOC.
+         */
+        if (page->pfmemalloc && !page->mapping)
+                skb->pfmemalloc = true;
         frag->page.p              = page;
         frag->page_offset         = off;
         skb_frag_size_set(frag, size);
@@ -1753,6 +1774,61 @@ static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev,
         return __netdev_alloc_skb_ip_align(dev, length, GFP_ATOMIC);
 }
 
+/*
+ *      __skb_alloc_page - allocate pages for ps-rx on a skb and preserve pfmemalloc data
+ *      @gfp_mask: alloc_pages_node mask. Set __GFP_NOMEMALLOC if not for network packet RX
+ *      @skb: skb to set pfmemalloc on if __GFP_MEMALLOC is used
+ *      @order: size of the allocation
+ *
+ *      Allocate a new page.
+ *
+ *      %NULL is returned if there is no free memory.
+*/
+static inline struct page *__skb_alloc_pages(gfp_t gfp_mask,
+                                              struct sk_buff *skb,
+                                              unsigned int order)
+{
+        struct page *page;
+
+        gfp_mask |= __GFP_COLD;
+
+        if (!(gfp_mask & __GFP_NOMEMALLOC))
+                gfp_mask |= __GFP_MEMALLOC;
+
+        page = alloc_pages_node(NUMA_NO_NODE, gfp_mask, order);
+        if (skb && page && page->pfmemalloc)
+                skb->pfmemalloc = true;
+
+        return page;
+}
+
+/**
+ *      __skb_alloc_page - allocate a page for ps-rx for a given skb and preserve pfmemalloc data
+ *      @gfp_mask: alloc_pages_node mask. Set __GFP_NOMEMALLOC if not for network packet RX
+ *      @skb: skb to set pfmemalloc on if __GFP_MEMALLOC is used
+ *
+ *      Allocate a new page.
+ *
+ *      %NULL is returned if there is no free memory.
+ */
+static inline struct page *__skb_alloc_page(gfp_t gfp_mask,
+                                             struct sk_buff *skb)
+{
+        return __skb_alloc_pages(gfp_mask, skb, 0);
+}
+
+/**
+ *      skb_propagate_pfmemalloc - Propagate pfmemalloc if skb is allocated after RX page
+ *      @page: The page that was allocated from skb_alloc_page
+ *      @skb: The skb that may need pfmemalloc set
+ */
+static inline void skb_propagate_pfmemalloc(struct page *page,
+                                             struct sk_buff *skb)
+{
+        if (page && page->pfmemalloc)
+                skb->pfmemalloc = true;
+}
+
 /**
  * skb_frag_page - retrieve the page refered to by a paged fragment
  * @frag: the paged fragment