[PATCH net-next 1/6] mm/page_alloc: modify page_frag_alloc_align() to accept align as an argument

[Yunsheng Lin]

napi_alloc_frag_align() and netdev_alloc_frag_align() accept
align as an argument, and they are thin wrappers around the
__napi_alloc_frag_align() and __netdev_alloc_frag_align() APIs
doing the align and align_mask conversion, in order to call
page_frag_alloc_align() directly.

As __napi_alloc_frag_align() and __netdev_alloc_frag_align()
APIs are only used by the above thin wrappers, it seems that
it makes more sense to remove align and align_mask conversion
and call page_frag_alloc_align() directly. By doing that, we
can also avoid the confusion between napi_alloc_frag_align()
accepting align as an argument and page_frag_alloc_align()
accepting align_mask as an argument when they both have the
'align' suffix.

Signed-off-by: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
CC: Alexander Duyck <alexander.duyck@xxxxxxxxx>
---
 include/linux/gfp.h    |  4 ++--
 include/linux/skbuff.h | 22 ++++------------------
 mm/page_alloc.c        |  6 ++++--
 net/core/skbuff.c      | 14 +++++++-------
 4 files changed, 17 insertions(+), 29 deletions(-)

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index de292a007138..bbd75976541e 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -314,12 +314,12 @@ struct page_frag_cache;
 extern void __page_frag_cache_drain(struct page *page, unsigned int count);
 extern void *page_frag_alloc_align(struct page_frag_cache *nc,
 				   unsigned int fragsz, gfp_t gfp_mask,
-				   unsigned int align_mask);
+				   unsigned int align);
 
 static inline void *page_frag_alloc(struct page_frag_cache *nc,
 			     unsigned int fragsz, gfp_t gfp_mask)
 {
-	return page_frag_alloc_align(nc, fragsz, gfp_mask, ~0u);
+	return page_frag_alloc_align(nc, fragsz, gfp_mask, 1);
 }
 
 extern void page_frag_free(void *addr);
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index a5ae952454c8..c0a3b44ef5da 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3192,7 +3192,7 @@ static inline void skb_queue_purge(struct sk_buff_head *list)
 unsigned int skb_rbtree_purge(struct rb_root *root);
 void skb_errqueue_purge(struct sk_buff_head *list);
 
-void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align_mask);
+void *netdev_alloc_frag_align(unsigned int fragsz, unsigned int align);
 
 /**
  * netdev_alloc_frag - allocate a page fragment
@@ -3203,14 +3203,7 @@ void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align_mask);
  */
 static inline void *netdev_alloc_frag(unsigned int fragsz)
 {
-	return __netdev_alloc_frag_align(fragsz, ~0u);
-}
-
-static inline void *netdev_alloc_frag_align(unsigned int fragsz,
-					    unsigned int align)
-{
-	WARN_ON_ONCE(!is_power_of_2(align));
-	return __netdev_alloc_frag_align(fragsz, -align);
+	return netdev_alloc_frag_align(fragsz, 1);
 }
 
 struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int length,
@@ -3270,18 +3263,11 @@ static inline void skb_free_frag(void *addr)
 	page_frag_free(addr);
 }
 
-void *__napi_alloc_frag_align(unsigned int fragsz, unsigned int align_mask);
+void *napi_alloc_frag_align(unsigned int fragsz, unsigned int align);
 
 static inline void *napi_alloc_frag(unsigned int fragsz)
 {
-	return __napi_alloc_frag_align(fragsz, ~0u);
-}
-
-static inline void *napi_alloc_frag_align(unsigned int fragsz,
-					  unsigned int align)
-{
-	WARN_ON_ONCE(!is_power_of_2(align));
-	return __napi_alloc_frag_align(fragsz, -align);
+	return napi_alloc_frag_align(fragsz, 1);
 }
 
 struct sk_buff *__napi_alloc_skb(struct napi_struct *napi,
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 37ca4f4b62bf..9a16305cf985 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4718,12 +4718,14 @@ EXPORT_SYMBOL(__page_frag_cache_drain);
 
 void *page_frag_alloc_align(struct page_frag_cache *nc,
 		      unsigned int fragsz, gfp_t gfp_mask,
-		      unsigned int align_mask)
+		      unsigned int align)
 {
 	unsigned int size = PAGE_SIZE;
 	struct page *page;
 	int offset;
 
+	WARN_ON_ONCE(!is_power_of_2(align));
+
 	if (unlikely(!nc->va)) {
 refill:
 		page = __page_frag_cache_refill(nc, gfp_mask);
@@ -4782,7 +4784,7 @@ void *page_frag_alloc_align(struct page_frag_cache *nc,
 	}
 
 	nc->pagecnt_bias--;
-	offset &= align_mask;
+	offset &= -align;
 	nc->offset = offset;
 
 	return nc->va + offset;
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 12d22c0b8551..84c29a48f1a8 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -291,17 +291,17 @@ void napi_get_frags_check(struct napi_struct *napi)
 	local_bh_enable();
 }
 
-void *__napi_alloc_frag_align(unsigned int fragsz, unsigned int align_mask)
+void *napi_alloc_frag_align(unsigned int fragsz, unsigned int align)
 {
 	struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
 
 	fragsz = SKB_DATA_ALIGN(fragsz);
 
-	return page_frag_alloc_align(&nc->page, fragsz, GFP_ATOMIC, align_mask);
+	return page_frag_alloc_align(&nc->page, fragsz, GFP_ATOMIC, align);
 }
-EXPORT_SYMBOL(__napi_alloc_frag_align);
+EXPORT_SYMBOL(napi_alloc_frag_align);
 
-void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align_mask)
+void *netdev_alloc_frag_align(unsigned int fragsz, unsigned int align)
 {
 	void *data;
 
@@ -309,18 +309,18 @@ void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align_mask)
 	if (in_hardirq() || irqs_disabled()) {
 		struct page_frag_cache *nc = this_cpu_ptr(&netdev_alloc_cache);
 
-		data = page_frag_alloc_align(nc, fragsz, GFP_ATOMIC, align_mask);
+		data = page_frag_alloc_align(nc, fragsz, GFP_ATOMIC, align);
 	} else {
 		struct napi_alloc_cache *nc;
 
 		local_bh_disable();
 		nc = this_cpu_ptr(&napi_alloc_cache);
-		data = page_frag_alloc_align(&nc->page, fragsz, GFP_ATOMIC, align_mask);
+		data = page_frag_alloc_align(&nc->page, fragsz, GFP_ATOMIC, align);
 		local_bh_enable();
 	}
 	return data;
 }
-EXPORT_SYMBOL(__netdev_alloc_frag_align);
+EXPORT_SYMBOL(netdev_alloc_frag_align);
 
 static struct sk_buff *napi_skb_cache_get(void)
 {
-- 
2.33.0