Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

Pull networking updates from David Miller:

 1) Add Maglev hashing scheduler to IPVS, from Inju Song.

 2) Lots of new TC subsystem tests from Roman Mashak.

 3) Add TCP zero copy receive and fix delayed acks and autotuning with
    SO_RCVLOWAT, from Eric Dumazet.

 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard
    Brouer.

 5) Add ttl inherit support to vxlan, from Hangbin Liu.

 6) Properly separate ipv6 routes into their logically independant
    components. fib6_info for the routing table, and fib6_nh for sets of
    nexthops, which thus can be shared. From David Ahern.

 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP
    messages from XDP programs. From Nikita V. Shirokov.

 8) Lots of long overdue cleanups to the r8169 driver, from Heiner
    Kallweit.

 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau.

10) Add traffic condition monitoring to iwlwifi, from Luca Coelho.

11) Plumb extack down into fib_rules, from Roopa Prabhu.

12) Add Flower classifier offload support to igb, from Vinicius Costa
    Gomes.

13) Add UDP GSO support, from Willem de Bruijn.

14) Add documentation for eBPF helpers, from Quentin Monnet.

15) Add TLS tx offload to mlx5, from Ilya Lesokhin.

16) Allow applications to be given the number of bytes available to read
    on a socket via a control message returned from recvmsg(), from
    Soheil Hassas Yeganeh.

17) Add x86_32 eBPF JIT compiler, from Wang YanQing.

18) Add AF_XDP sockets, with zerocopy support infrastructure as well.
    From Björn Töpel.

19) Remove indirect load support from all of the BPF JITs and handle
    these operations in the verifier by translating them into native BPF
    instead. From Daniel Borkmann.

20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha.

21) Allow XDP programs to do lookups in the main kernel routing tables
    for forwarding. From David Ahern.

22) Allow drivers to store hardware state into an ELF section of kernel
    dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy.

23) Various RACK and loss detection improvements in TCP, from Yuchung
    Cheng.

24) Add TCP SACK compression, from Eric Dumazet.

25) Add User Mode Helper support and basic bpfilter infrastructure, from
    Alexei Starovoitov.

26) Support ports and protocol values in RTM_GETROUTE, from Roopa
    Prabhu.

27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard
    Brouer.

28) Add lots of forwarding selftests, from Petr Machata.

29) Add generic network device failover driver, from Sridhar Samudrala.

* ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits)
  strparser: Add __strp_unpause and use it in ktls.
  rxrpc: Fix terminal retransmission connection ID to include the channel
  net: hns3: Optimize PF CMDQ interrupt switching process
  net: hns3: Fix for VF mailbox receiving unknown message
  net: hns3: Fix for VF mailbox cannot receiving PF response
  bnx2x: use the right constant
  Revert "net: sched: cls: Fix offloading when ingress dev is vxlan"
  net: dsa: b53: Fix for brcm tag issue in Cygnus SoC
  enic: fix UDP rss bits
  netdev-FAQ: clarify DaveM's position for stable backports
  rtnetlink: validate attributes in do_setlink()
  mlxsw: Add extack messages for port_{un, }split failures
  netdevsim: Add extack error message for devlink reload
  devlink: Add extack to reload and port_{un, }split operations
  net: metrics: add proper netlink validation
  ipmr: fix error path when ipmr_new_table fails
  ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds
  net: hns3: remove unused hclgevf_cfg_func_mta_filter
  netfilter: provide udp*_lib_lookup for nf_tproxy
  qed*: Utilize FW 8.37.2.0
  ...

1 files changed, 317 insertions, 0 deletions

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
new file mode 100644
index 000000000000..68bf07206744
--- /dev/null
+++ b/net/core/page_pool.c
@@ -0,0 +1,317 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * page_pool.c
+ *	Author:	Jesper Dangaard Brouer <netoptimizer@brouer.com>
+ *	Copyright (C) 2016 Red Hat, Inc.
+ */
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+#include <net/page_pool.h>
+#include <linux/dma-direction.h>
+#include <linux/dma-mapping.h>
+#include <linux/page-flags.h>
+#include <linux/mm.h> /* for __put_page() */
+
+static int page_pool_init(struct page_pool *pool,
+			  const struct page_pool_params *params)
+{
+	unsigned int ring_qsize = 1024; /* Default */
+
+	memcpy(&pool->p, params, sizeof(pool->p));
+
+	/* Validate only known flags were used */
+	if (pool->p.flags & ~(PP_FLAG_ALL))
+		return -EINVAL;
+
+	if (pool->p.pool_size)
+		ring_qsize = pool->p.pool_size;
+
+	/* Sanity limit mem that can be pinned down */
+	if (ring_qsize > 32768)
+		return -E2BIG;
+
+	/* DMA direction is either DMA_FROM_DEVICE or DMA_BIDIRECTIONAL.
+	 * DMA_BIDIRECTIONAL is for allowing page used for DMA sending,
+	 * which is the XDP_TX use-case.
+	 */
+	if ((pool->p.dma_dir != DMA_FROM_DEVICE) &&
+	    (pool->p.dma_dir != DMA_BIDIRECTIONAL))
+		return -EINVAL;
+
+	if (ptr_ring_init(&pool->ring, ring_qsize, GFP_KERNEL) < 0)
+		return -ENOMEM;
+
+	return 0;
+}
+
+struct page_pool *page_pool_create(const struct page_pool_params *params)
+{
+	struct page_pool *pool;
+	int err = 0;
+
+	pool = kzalloc_node(sizeof(*pool), GFP_KERNEL, params->nid);
+	if (!pool)
+		return ERR_PTR(-ENOMEM);
+
+	err = page_pool_init(pool, params);
+	if (err < 0) {
+		pr_warn("%s() gave up with errno %d\n", __func__, err);
+		kfree(pool);
+		return ERR_PTR(err);
+	}
+	return pool;
+}
+EXPORT_SYMBOL(page_pool_create);
+
+/* fast path */
+static struct page *__page_pool_get_cached(struct page_pool *pool)
+{
+	struct ptr_ring *r = &pool->ring;
+	struct page *page;
+
+	/* Quicker fallback, avoid locks when ring is empty */
+	if (__ptr_ring_empty(r))
+		return NULL;
+
+	/* Test for safe-context, caller should provide this guarantee */
+	if (likely(in_serving_softirq())) {
+		if (likely(pool->alloc.count)) {
+			/* Fast-path */
+			page = pool->alloc.cache[--pool->alloc.count];
+			return page;
+		}
+		/* Slower-path: Alloc array empty, time to refill
+		 *
+		 * Open-coded bulk ptr_ring consumer.
+		 *
+		 * Discussion: the ring consumer lock is not really
+		 * needed due to the softirq/NAPI protection, but
+		 * later need the ability to reclaim pages on the
+		 * ring. Thus, keeping the locks.
+		 */
+		spin_lock(&r->consumer_lock);
+		while ((page = __ptr_ring_consume(r))) {
+			if (pool->alloc.count == PP_ALLOC_CACHE_REFILL)
+				break;
+			pool->alloc.cache[pool->alloc.count++] = page;
+		}
+		spin_unlock(&r->consumer_lock);
+		return page;
+	}
+
+	/* Slow-path: Get page from locked ring queue */
+	page = ptr_ring_consume(&pool->ring);
+	return page;
+}
+
+/* slow path */
+noinline
+static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool,
+						 gfp_t _gfp)
+{
+	struct page *page;
+	gfp_t gfp = _gfp;
+	dma_addr_t dma;
+
+	/* We could always set __GFP_COMP, and avoid this branch, as
+	 * prep_new_page() can handle order-0 with __GFP_COMP.
+	 */
+	if (pool->p.order)
+		gfp |= __GFP_COMP;
+
+	/* FUTURE development:
+	 *
+	 * Current slow-path essentially falls back to single page
+	 * allocations, which doesn't improve performance.  This code
+	 * need bulk allocation support from the page allocator code.
+	 */
+
+	/* Cache was empty, do real allocation */
+	page = alloc_pages_node(pool->p.nid, gfp, pool->p.order);
+	if (!page)
+		return NULL;
+
+	if (!(pool->p.flags & PP_FLAG_DMA_MAP))
+		goto skip_dma_map;
+
+	/* Setup DMA mapping: use page->private for DMA-addr
+	 * This mapping is kept for lifetime of page, until leaving pool.
+	 */
+	dma = dma_map_page(pool->p.dev, page, 0,
+			   (PAGE_SIZE << pool->p.order),
+			   pool->p.dma_dir);
+	if (dma_mapping_error(pool->p.dev, dma)) {
+		put_page(page);
+		return NULL;
+	}
+	set_page_private(page, dma); /* page->private = dma; */
+
+skip_dma_map:
+	/* When page just alloc'ed is should/must have refcnt 1. */
+	return page;
+}
+
+/* For using page_pool replace: alloc_pages() API calls, but provide
+ * synchronization guarantee for allocation side.
+ */
+struct page *page_pool_alloc_pages(struct page_pool *pool, gfp_t gfp)
+{
+	struct page *page;
+
+	/* Fast-path: Get a page from cache */
+	page = __page_pool_get_cached(pool);
+	if (page)
+		return page;
+
+	/* Slow-path: cache empty, do real allocation */
+	page = __page_pool_alloc_pages_slow(pool, gfp);
+	return page;
+}
+EXPORT_SYMBOL(page_pool_alloc_pages);
+
+/* Cleanup page_pool state from page */
+static void __page_pool_clean_page(struct page_pool *pool,
+				   struct page *page)
+{
+	if (!(pool->p.flags & PP_FLAG_DMA_MAP))
+		return;
+
+	/* DMA unmap */
+	dma_unmap_page(pool->p.dev, page_private(page),
+		       PAGE_SIZE << pool->p.order, pool->p.dma_dir);
+	set_page_private(page, 0);
+}
+
+/* Return a page to the page allocator, cleaning up our state */
+static void __page_pool_return_page(struct page_pool *pool, struct page *page)
+{
+	__page_pool_clean_page(pool, page);
+	put_page(page);
+	/* An optimization would be to call __free_pages(page, pool->p.order)
+	 * knowing page is not part of page-cache (thus avoiding a
+	 * __page_cache_release() call).
+	 */
+}
+
+static bool __page_pool_recycle_into_ring(struct page_pool *pool,
+				   struct page *page)
+{
+	int ret;
+	/* BH protection not needed if current is serving softirq */
+	if (in_serving_softirq())
+		ret = ptr_ring_produce(&pool->ring, page);
+	else
+		ret = ptr_ring_produce_bh(&pool->ring, page);
+
+	return (ret == 0) ? true : false;
+}
+
+/* Only allow direct recycling in special circumstances, into the
+ * alloc side cache.  E.g. during RX-NAPI processing for XDP_DROP use-case.
+ *
+ * Caller must provide appropriate safe context.
+ */
+static bool __page_pool_recycle_direct(struct page *page,
+				       struct page_pool *pool)
+{
+	if (unlikely(pool->alloc.count == PP_ALLOC_CACHE_SIZE))
+		return false;
+
+	/* Caller MUST have verified/know (page_ref_count(page) == 1) */
+	pool->alloc.cache[pool->alloc.count++] = page;
+	return true;
+}
+
+void __page_pool_put_page(struct page_pool *pool,
+			  struct page *page, bool allow_direct)
+{
+	/* This allocator is optimized for the XDP mode that uses
+	 * one-frame-per-page, but have fallbacks that act like the
+	 * regular page allocator APIs.
+	 *
+	 * refcnt == 1 means page_pool owns page, and can recycle it.
+	 */
+	if (likely(page_ref_count(page) == 1)) {
+		/* Read barrier done in page_ref_count / READ_ONCE */
+
+		if (allow_direct && in_serving_softirq())
+			if (__page_pool_recycle_direct(page, pool))
+				return;
+
+		if (!__page_pool_recycle_into_ring(pool, page)) {
+			/* Cache full, fallback to free pages */
+			__page_pool_return_page(pool, page);
+		}
+		return;
+	}
+	/* Fallback/non-XDP mode: API user have elevated refcnt.
+	 *
+	 * Many drivers split up the page into fragments, and some
+	 * want to keep doing this to save memory and do refcnt based
+	 * recycling. Support this use case too, to ease drivers
+	 * switching between XDP/non-XDP.
+	 *
+	 * In-case page_pool maintains the DMA mapping, API user must
+	 * call page_pool_put_page once.  In this elevated refcnt
+	 * case, the DMA is unmapped/released, as driver is likely
+	 * doing refcnt based recycle tricks, meaning another process
+	 * will be invoking put_page.
+	 */
+	__page_pool_clean_page(pool, page);
+	put_page(page);
+}
+EXPORT_SYMBOL(__page_pool_put_page);
+
+static void __page_pool_empty_ring(struct page_pool *pool)
+{
+	struct page *page;
+
+	/* Empty recycle ring */
+	while ((page = ptr_ring_consume(&pool->ring))) {
+		/* Verify the refcnt invariant of cached pages */
+		if (!(page_ref_count(page) == 1))
+			pr_crit("%s() page_pool refcnt %d violation\n",
+				__func__, page_ref_count(page));
+
+		__page_pool_return_page(pool, page);
+	}
+}
+
+static void __page_pool_destroy_rcu(struct rcu_head *rcu)
+{
+	struct page_pool *pool;
+
+	pool = container_of(rcu, struct page_pool, rcu);
+
+	WARN(pool->alloc.count, "API usage violation");
+
+	__page_pool_empty_ring(pool);
+	ptr_ring_cleanup(&pool->ring, NULL);
+	kfree(pool);
+}
+
+/* Cleanup and release resources */
+void page_pool_destroy(struct page_pool *pool)
+{
+	struct page *page;
+
+	/* Empty alloc cache, assume caller made sure this is
+	 * no-longer in use, and page_pool_alloc_pages() cannot be
+	 * call concurrently.
+	 */
+	while (pool->alloc.count) {
+		page = pool->alloc.cache[--pool->alloc.count];
+		__page_pool_return_page(pool, page);
+	}
+
+	/* No more consumers should exist, but producers could still
+	 * be in-flight.
+	 */
+	__page_pool_empty_ring(pool);
+
+	/* An xdp_mem_allocator can still ref page_pool pointer */
+	call_rcu(&pool->rcu, __page_pool_destroy_rcu);
+}
+EXPORT_SYMBOL(page_pool_destroy);