diff options
| -rw-r--r-- | drivers/net/ethernet/broadcom/bnx2.c | 2 | ||||
| -rw-r--r-- | drivers/net/ethernet/qlogic/qed/qed_ll2.c | 2 | ||||
| -rw-r--r-- | include/linux/skbuff.h | 1 | ||||
| -rw-r--r-- | net/bpf/test_run.c | 2 | ||||
| -rw-r--r-- | net/core/skbuff.c | 70 |
5 files changed, 66 insertions, 11 deletions
diff --git a/drivers/net/ethernet/broadcom/bnx2.c b/drivers/net/ethernet/broadcom/bnx2.c index dbe310144780..9f473854b0f4 100644 --- a/drivers/net/ethernet/broadcom/bnx2.c +++ b/drivers/net/ethernet/broadcom/bnx2.c @@ -3045,7 +3045,7 @@ error: dma_unmap_single(&bp->pdev->dev, dma_addr, bp->rx_buf_use_size, DMA_FROM_DEVICE); - skb = build_skb(data, 0); + skb = slab_build_skb(data); if (!skb) { kfree(data); goto error; diff --git a/drivers/net/ethernet/qlogic/qed/qed_ll2.c b/drivers/net/ethernet/qlogic/qed/qed_ll2.c index ed274f033626..e5116a86cfbc 100644 --- a/drivers/net/ethernet/qlogic/qed/qed_ll2.c +++ b/drivers/net/ethernet/qlogic/qed/qed_ll2.c @@ -200,7 +200,7 @@ static void qed_ll2b_complete_rx_packet(void *cxt, dma_unmap_single(&cdev->pdev->dev, buffer->phys_addr, cdev->ll2->rx_size, DMA_FROM_DEVICE); - skb = build_skb(buffer->data, 0); + skb = slab_build_skb(buffer->data); if (!skb) { DP_INFO(cdev, "Failed to build SKB\n"); kfree(buffer->data); diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 4e464a27adaf..4c8492401a10 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1255,6 +1255,7 @@ struct sk_buff *build_skb_around(struct sk_buff *skb, void skb_attempt_defer_free(struct sk_buff *skb); struct sk_buff *napi_build_skb(void *data, unsigned int frag_size); +struct sk_buff *slab_build_skb(void *data); /** * alloc_skb - allocate a network buffer diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index 6094ef7cffcd..c9bfd263dcef 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -1128,7 +1128,7 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr, } sock_init_data(NULL, sk); - skb = build_skb(data, 0); + skb = slab_build_skb(data); if (!skb) { kfree(data); kfree(ctx); diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 4bf95e36ed16..3cbba7099c0f 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -270,12 +270,10 @@ static struct sk_buff *napi_skb_cache_get(void) return skb; } -/* Caller must provide SKB that is memset cleared */ -static void __build_skb_around(struct sk_buff *skb, void *data, - unsigned int frag_size) +static inline void __finalize_skb_around(struct sk_buff *skb, void *data, + unsigned int size) { struct skb_shared_info *shinfo; - unsigned int size = frag_size ? : ksize(data); size -= SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); @@ -297,15 +295,71 @@ static void __build_skb_around(struct sk_buff *skb, void *data, skb_set_kcov_handle(skb, kcov_common_handle()); } +static inline void *__slab_build_skb(struct sk_buff *skb, void *data, + unsigned int *size) +{ + void *resized; + + /* Must find the allocation size (and grow it to match). */ + *size = ksize(data); + /* krealloc() will immediately return "data" when + * "ksize(data)" is requested: it is the existing upper + * bounds. As a result, GFP_ATOMIC will be ignored. Note + * that this "new" pointer needs to be passed back to the + * caller for use so the __alloc_size hinting will be + * tracked correctly. + */ + resized = krealloc(data, *size, GFP_ATOMIC); + WARN_ON_ONCE(resized != data); + return resized; +} + +/* build_skb() variant which can operate on slab buffers. + * Note that this should be used sparingly as slab buffers + * cannot be combined efficiently by GRO! + */ +struct sk_buff *slab_build_skb(void *data) +{ + struct sk_buff *skb; + unsigned int size; + + skb = kmem_cache_alloc(skbuff_head_cache, GFP_ATOMIC); + if (unlikely(!skb)) + return NULL; + + memset(skb, 0, offsetof(struct sk_buff, tail)); + data = __slab_build_skb(skb, data, &size); + __finalize_skb_around(skb, data, size); + + return skb; +} +EXPORT_SYMBOL(slab_build_skb); + +/* Caller must provide SKB that is memset cleared */ +static void __build_skb_around(struct sk_buff *skb, void *data, + unsigned int frag_size) +{ + unsigned int size = frag_size; + + /* frag_size == 0 is considered deprecated now. Callers + * using slab buffer should use slab_build_skb() instead. + */ + if (WARN_ONCE(size == 0, "Use slab_build_skb() instead")) + data = __slab_build_skb(skb, data, &size); + + __finalize_skb_around(skb, data, size); +} + /** * __build_skb - build a network buffer * @data: data buffer provided by caller - * @frag_size: size of data, or 0 if head was kmalloced + * @frag_size: size of data (must not be 0) * * Allocate a new &sk_buff. Caller provides space holding head and - * skb_shared_info. @data must have been allocated by kmalloc() only if - * @frag_size is 0, otherwise data should come from the page allocator - * or vmalloc() + * skb_shared_info. @data must have been allocated from the page + * allocator or vmalloc(). (A @frag_size of 0 to indicate a kmalloc() + * allocation is deprecated, and callers should use slab_build_skb() + * instead.) * The return is the new skb buffer. * On a failure the return is %NULL, and @data is not freed. * Notes : |