Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 962 insertions, 0 deletions

diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
new file mode 100644
index 000000000..273a0fe79
--- /dev/null
+++ b/kernel/events/ring_buffer.c
@@ -0,0 +1,962 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Performance events ring-buffer code:
+ *
+ *  Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
+ *  Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar
+ *  Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra
+ *  Copyright  ©  2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
+ */
+
+#include <linux/perf_event.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/circ_buf.h>
+#include <linux/poll.h>
+#include <linux/nospec.h>
+
+#include "internal.h"
+
+static void perf_output_wakeup(struct perf_output_handle *handle)
+{
+	atomic_set(&handle->rb->poll, EPOLLIN);
+
+	handle->event->pending_wakeup = 1;
+	irq_work_queue(&handle->event->pending_irq);
+}
+
+/*
+ * We need to ensure a later event_id doesn't publish a head when a former
+ * event isn't done writing. However since we need to deal with NMIs we
+ * cannot fully serialize things.
+ *
+ * We only publish the head (and generate a wakeup) when the outer-most
+ * event completes.
+ */
+static void perf_output_get_handle(struct perf_output_handle *handle)
+{
+	struct perf_buffer *rb = handle->rb;
+
+	preempt_disable();
+
+	/*
+	 * Avoid an explicit LOAD/STORE such that architectures with memops
+	 * can use them.
+	 */
+	(*(volatile unsigned int *)&rb->nest)++;
+	handle->wakeup = local_read(&rb->wakeup);
+}
+
+static void perf_output_put_handle(struct perf_output_handle *handle)
+{
+	struct perf_buffer *rb = handle->rb;
+	unsigned long head;
+	unsigned int nest;
+
+	/*
+	 * If this isn't the outermost nesting, we don't have to update
+	 * @rb->user_page->data_head.
+	 */
+	nest = READ_ONCE(rb->nest);
+	if (nest > 1) {
+		WRITE_ONCE(rb->nest, nest - 1);
+		goto out;
+	}
+
+again:
+	/*
+	 * In order to avoid publishing a head value that goes backwards,
+	 * we must ensure the load of @rb->head happens after we've
+	 * incremented @rb->nest.
+	 *
+	 * Otherwise we can observe a @rb->head value before one published
+	 * by an IRQ/NMI happening between the load and the increment.
+	 */
+	barrier();
+	head = local_read(&rb->head);
+
+	/*
+	 * IRQ/NMI can happen here and advance @rb->head, causing our
+	 * load above to be stale.
+	 */
+
+	/*
+	 * Since the mmap() consumer (userspace) can run on a different CPU:
+	 *
+	 *   kernel				user
+	 *
+	 *   if (LOAD ->data_tail) {		LOAD ->data_head
+	 *			(A)		smp_rmb()	(C)
+	 *	STORE $data			LOAD $data
+	 *	smp_wmb()	(B)		smp_mb()	(D)
+	 *	STORE ->data_head		STORE ->data_tail
+	 *   }
+	 *
+	 * Where A pairs with D, and B pairs with C.
+	 *
+	 * In our case (A) is a control dependency that separates the load of
+	 * the ->data_tail and the stores of $data. In case ->data_tail
+	 * indicates there is no room in the buffer to store $data we do not.
+	 *
+	 * D needs to be a full barrier since it separates the data READ
+	 * from the tail WRITE.
+	 *
+	 * For B a WMB is sufficient since it separates two WRITEs, and for C
+	 * an RMB is sufficient since it separates two READs.
+	 *
+	 * See perf_output_begin().
+	 */
+	smp_wmb(); /* B, matches C */
+	WRITE_ONCE(rb->user_page->data_head, head);
+
+	/*
+	 * We must publish the head before decrementing the nest count,
+	 * otherwise an IRQ/NMI can publish a more recent head value and our
+	 * write will (temporarily) publish a stale value.
+	 */
+	barrier();
+	WRITE_ONCE(rb->nest, 0);
+
+	/*
+	 * Ensure we decrement @rb->nest before we validate the @rb->head.
+	 * Otherwise we cannot be sure we caught the 'last' nested update.
+	 */
+	barrier();
+	if (unlikely(head != local_read(&rb->head))) {
+		WRITE_ONCE(rb->nest, 1);
+		goto again;
+	}
+
+	if (handle->wakeup != local_read(&rb->wakeup))
+		perf_output_wakeup(handle);
+
+out:
+	preempt_enable();
+}
+
+static __always_inline bool
+ring_buffer_has_space(unsigned long head, unsigned long tail,
+		      unsigned long data_size, unsigned int size,
+		      bool backward)
+{
+	if (!backward)
+		return CIRC_SPACE(head, tail, data_size) >= size;
+	else
+		return CIRC_SPACE(tail, head, data_size) >= size;
+}
+
+static __always_inline int
+__perf_output_begin(struct perf_output_handle *handle,
+		    struct perf_sample_data *data,
+		    struct perf_event *event, unsigned int size,
+		    bool backward)
+{
+	struct perf_buffer *rb;
+	unsigned long tail, offset, head;
+	int have_lost, page_shift;
+	struct {
+		struct perf_event_header header;
+		u64			 id;
+		u64			 lost;
+	} lost_event;
+
+	rcu_read_lock();
+	/*
+	 * For inherited events we send all the output towards the parent.
+	 */
+	if (event->parent)
+		event = event->parent;
+
+	rb = rcu_dereference(event->rb);
+	if (unlikely(!rb))
+		goto out;
+
+	if (unlikely(rb->paused)) {
+		if (rb->nr_pages) {
+			local_inc(&rb->lost);
+			atomic64_inc(&event->lost_samples);
+		}
+		goto out;
+	}
+
+	handle->rb    = rb;
+	handle->event = event;
+
+	have_lost = local_read(&rb->lost);
+	if (unlikely(have_lost)) {
+		size += sizeof(lost_event);
+		if (event->attr.sample_id_all)
+			size += event->id_header_size;
+	}
+
+	perf_output_get_handle(handle);
+
+	do {
+		tail = READ_ONCE(rb->user_page->data_tail);
+		offset = head = local_read(&rb->head);
+		if (!rb->overwrite) {
+			if (unlikely(!ring_buffer_has_space(head, tail,
+							    perf_data_size(rb),
+							    size, backward)))
+				goto fail;
+		}
+
+		/*
+		 * The above forms a control dependency barrier separating the
+		 * @tail load above from the data stores below. Since the @tail
+		 * load is required to compute the branch to fail below.
+		 *
+		 * A, matches D; the full memory barrier userspace SHOULD issue
+		 * after reading the data and before storing the new tail
+		 * position.
+		 *
+		 * See perf_output_put_handle().
+		 */
+
+		if (!backward)
+			head += size;
+		else
+			head -= size;
+	} while (local_cmpxchg(&rb->head, offset, head) != offset);
+
+	if (backward) {
+		offset = head;
+		head = (u64)(-head);
+	}
+
+	/*
+	 * We rely on the implied barrier() by local_cmpxchg() to ensure
+	 * none of the data stores below can be lifted up by the compiler.
+	 */
+
+	if (unlikely(head - local_read(&rb->wakeup) > rb->watermark))
+		local_add(rb->watermark, &rb->wakeup);
+
+	page_shift = PAGE_SHIFT + page_order(rb);
+
+	handle->page = (offset >> page_shift) & (rb->nr_pages - 1);
+	offset &= (1UL << page_shift) - 1;
+	handle->addr = rb->data_pages[handle->page] + offset;
+	handle->size = (1UL << page_shift) - offset;
+
+	if (unlikely(have_lost)) {
+		lost_event.header.size = sizeof(lost_event);
+		lost_event.header.type = PERF_RECORD_LOST;
+		lost_event.header.misc = 0;
+		lost_event.id          = event->id;
+		lost_event.lost        = local_xchg(&rb->lost, 0);
+
+		/* XXX mostly redundant; @data is already fully initializes */
+		perf_event_header__init_id(&lost_event.header, data, event);
+		perf_output_put(handle, lost_event);
+		perf_event__output_id_sample(event, handle, data);
+	}
+
+	return 0;
+
+fail:
+	local_inc(&rb->lost);
+	atomic64_inc(&event->lost_samples);
+	perf_output_put_handle(handle);
+out:
+	rcu_read_unlock();
+
+	return -ENOSPC;
+}
+
+int perf_output_begin_forward(struct perf_output_handle *handle,
+			      struct perf_sample_data *data,
+			      struct perf_event *event, unsigned int size)
+{
+	return __perf_output_begin(handle, data, event, size, false);
+}
+
+int perf_output_begin_backward(struct perf_output_handle *handle,
+			       struct perf_sample_data *data,
+			       struct perf_event *event, unsigned int size)
+{
+	return __perf_output_begin(handle, data, event, size, true);
+}
+
+int perf_output_begin(struct perf_output_handle *handle,
+		      struct perf_sample_data *data,
+		      struct perf_event *event, unsigned int size)
+{
+
+	return __perf_output_begin(handle, data, event, size,
+				   unlikely(is_write_backward(event)));
+}
+
+unsigned int perf_output_copy(struct perf_output_handle *handle,
+		      const void *buf, unsigned int len)
+{
+	return __output_copy(handle, buf, len);
+}
+
+unsigned int perf_output_skip(struct perf_output_handle *handle,
+			      unsigned int len)
+{
+	return __output_skip(handle, NULL, len);
+}
+
+void perf_output_end(struct perf_output_handle *handle)
+{
+	perf_output_put_handle(handle);
+	rcu_read_unlock();
+}
+
+static void
+ring_buffer_init(struct perf_buffer *rb, long watermark, int flags)
+{
+	long max_size = perf_data_size(rb);
+
+	if (watermark)
+		rb->watermark = min(max_size, watermark);
+
+	if (!rb->watermark)
+		rb->watermark = max_size / 2;
+
+	if (flags & RING_BUFFER_WRITABLE)
+		rb->overwrite = 0;
+	else
+		rb->overwrite = 1;
+
+	refcount_set(&rb->refcount, 1);
+
+	INIT_LIST_HEAD(&rb->event_list);
+	spin_lock_init(&rb->event_lock);
+
+	/*
+	 * perf_output_begin() only checks rb->paused, therefore
+	 * rb->paused must be true if we have no pages for output.
+	 */
+	if (!rb->nr_pages)
+		rb->paused = 1;
+}
+
+void perf_aux_output_flag(struct perf_output_handle *handle, u64 flags)
+{
+	/*
+	 * OVERWRITE is determined by perf_aux_output_end() and can't
+	 * be passed in directly.
+	 */
+	if (WARN_ON_ONCE(flags & PERF_AUX_FLAG_OVERWRITE))
+		return;
+
+	handle->aux_flags |= flags;
+}
+EXPORT_SYMBOL_GPL(perf_aux_output_flag);
+
+/*
+ * This is called before hardware starts writing to the AUX area to
+ * obtain an output handle and make sure there's room in the buffer.
+ * When the capture completes, call perf_aux_output_end() to commit
+ * the recorded data to the buffer.
+ *
+ * The ordering is similar to that of perf_output_{begin,end}, with
+ * the exception of (B), which should be taken care of by the pmu
+ * driver, since ordering rules will differ depending on hardware.
+ *
+ * Call this from pmu::start(); see the comment in perf_aux_output_end()
+ * about its use in pmu callbacks. Both can also be called from the PMI
+ * handler if needed.
+ */
+void *perf_aux_output_begin(struct perf_output_handle *handle,
+			    struct perf_event *event)
+{
+	struct perf_event *output_event = event;
+	unsigned long aux_head, aux_tail;
+	struct perf_buffer *rb;
+	unsigned int nest;
+
+	if (output_event->parent)
+		output_event = output_event->parent;
+
+	/*
+	 * Since this will typically be open across pmu::add/pmu::del, we
+	 * grab ring_buffer's refcount instead of holding rcu read lock
+	 * to make sure it doesn't disappear under us.
+	 */
+	rb = ring_buffer_get(output_event);
+	if (!rb)
+		return NULL;
+
+	if (!rb_has_aux(rb))
+		goto err;
+
+	/*
+	 * If aux_mmap_count is zero, the aux buffer is in perf_mmap_close(),
+	 * about to get freed, so we leave immediately.
+	 *
+	 * Checking rb::aux_mmap_count and rb::refcount has to be done in
+	 * the same order, see perf_mmap_close. Otherwise we end up freeing
+	 * aux pages in this path, which is a bug, because in_atomic().
+	 */
+	if (!atomic_read(&rb->aux_mmap_count))
+		goto err;
+
+	if (!refcount_inc_not_zero(&rb->aux_refcount))
+		goto err;
+
+	nest = READ_ONCE(rb->aux_nest);
+	/*
+	 * Nesting is not supported for AUX area, make sure nested
+	 * writers are caught early
+	 */
+	if (WARN_ON_ONCE(nest))
+		goto err_put;
+
+	WRITE_ONCE(rb->aux_nest, nest + 1);
+
+	aux_head = rb->aux_head;
+
+	handle->rb = rb;
+	handle->event = event;
+	handle->head = aux_head;
+	handle->size = 0;
+	handle->aux_flags = 0;
+
+	/*
+	 * In overwrite mode, AUX data stores do not depend on aux_tail,
+	 * therefore (A) control dependency barrier does not exist. The
+	 * (B) <-> (C) ordering is still observed by the pmu driver.
+	 */
+	if (!rb->aux_overwrite) {
+		aux_tail = READ_ONCE(rb->user_page->aux_tail);
+		handle->wakeup = rb->aux_wakeup + rb->aux_watermark;
+		if (aux_head - aux_tail < perf_aux_size(rb))
+			handle->size = CIRC_SPACE(aux_head, aux_tail, perf_aux_size(rb));
+
+		/*
+		 * handle->size computation depends on aux_tail load; this forms a
+		 * control dependency barrier separating aux_tail load from aux data
+		 * store that will be enabled on successful return
+		 */
+		if (!handle->size) { /* A, matches D */
+			event->pending_disable = smp_processor_id();
+			perf_output_wakeup(handle);
+			WRITE_ONCE(rb->aux_nest, 0);
+			goto err_put;
+		}
+	}
+
+	return handle->rb->aux_priv;
+
+err_put:
+	/* can't be last */
+	rb_free_aux(rb);
+
+err:
+	ring_buffer_put(rb);
+	handle->event = NULL;
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(perf_aux_output_begin);
+
+static __always_inline bool rb_need_aux_wakeup(struct perf_buffer *rb)
+{
+	if (rb->aux_overwrite)
+		return false;
+
+	if (rb->aux_head - rb->aux_wakeup >= rb->aux_watermark) {
+		rb->aux_wakeup = rounddown(rb->aux_head, rb->aux_watermark);
+		return true;
+	}
+
+	return false;
+}
+
+/*
+ * Commit the data written by hardware into the ring buffer by adjusting
+ * aux_head and posting a PERF_RECORD_AUX into the perf buffer. It is the
+ * pmu driver's responsibility to observe ordering rules of the hardware,
+ * so that all the data is externally visible before this is called.
+ *
+ * Note: this has to be called from pmu::stop() callback, as the assumption
+ * of the AUX buffer management code is that after pmu::stop(), the AUX
+ * transaction must be stopped and therefore drop the AUX reference count.
+ */
+void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size)
+{
+	bool wakeup = !!(handle->aux_flags & PERF_AUX_FLAG_TRUNCATED);
+	struct perf_buffer *rb = handle->rb;
+	unsigned long aux_head;
+
+	/* in overwrite mode, driver provides aux_head via handle */
+	if (rb->aux_overwrite) {
+		handle->aux_flags |= PERF_AUX_FLAG_OVERWRITE;
+
+		aux_head = handle->head;
+		rb->aux_head = aux_head;
+	} else {
+		handle->aux_flags &= ~PERF_AUX_FLAG_OVERWRITE;
+
+		aux_head = rb->aux_head;
+		rb->aux_head += size;
+	}
+
+	/*
+	 * Only send RECORD_AUX if we have something useful to communicate
+	 *
+	 * Note: the OVERWRITE records by themselves are not considered
+	 * useful, as they don't communicate any *new* information,
+	 * aside from the short-lived offset, that becomes history at
+	 * the next event sched-in and therefore isn't useful.
+	 * The userspace that needs to copy out AUX data in overwrite
+	 * mode should know to use user_page::aux_head for the actual
+	 * offset. So, from now on we don't output AUX records that
+	 * have *only* OVERWRITE flag set.
+	 */
+	if (size || (handle->aux_flags & ~(u64)PERF_AUX_FLAG_OVERWRITE))
+		perf_event_aux_event(handle->event, aux_head, size,
+				     handle->aux_flags);
+
+	WRITE_ONCE(rb->user_page->aux_head, rb->aux_head);
+	if (rb_need_aux_wakeup(rb))
+		wakeup = true;
+
+	if (wakeup) {
+		if (handle->aux_flags & PERF_AUX_FLAG_TRUNCATED)
+			handle->event->pending_disable = smp_processor_id();
+		perf_output_wakeup(handle);
+	}
+
+	handle->event = NULL;
+
+	WRITE_ONCE(rb->aux_nest, 0);
+	/* can't be last */
+	rb_free_aux(rb);
+	ring_buffer_put(rb);
+}
+EXPORT_SYMBOL_GPL(perf_aux_output_end);
+
+/*
+ * Skip over a given number of bytes in the AUX buffer, due to, for example,
+ * hardware's alignment constraints.
+ */
+int perf_aux_output_skip(struct perf_output_handle *handle, unsigned long size)
+{
+	struct perf_buffer *rb = handle->rb;
+
+	if (size > handle->size)
+		return -ENOSPC;
+
+	rb->aux_head += size;
+
+	WRITE_ONCE(rb->user_page->aux_head, rb->aux_head);
+	if (rb_need_aux_wakeup(rb)) {
+		perf_output_wakeup(handle);
+		handle->wakeup = rb->aux_wakeup + rb->aux_watermark;
+	}
+
+	handle->head = rb->aux_head;
+	handle->size -= size;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(perf_aux_output_skip);
+
+void *perf_get_aux(struct perf_output_handle *handle)
+{
+	/* this is only valid between perf_aux_output_begin and *_end */
+	if (!handle->event)
+		return NULL;
+
+	return handle->rb->aux_priv;
+}
+EXPORT_SYMBOL_GPL(perf_get_aux);
+
+/*
+ * Copy out AUX data from an AUX handle.
+ */
+long perf_output_copy_aux(struct perf_output_handle *aux_handle,
+			  struct perf_output_handle *handle,
+			  unsigned long from, unsigned long to)
+{
+	struct perf_buffer *rb = aux_handle->rb;
+	unsigned long tocopy, remainder, len = 0;
+	void *addr;
+
+	from &= (rb->aux_nr_pages << PAGE_SHIFT) - 1;
+	to &= (rb->aux_nr_pages << PAGE_SHIFT) - 1;
+
+	do {
+		tocopy = PAGE_SIZE - offset_in_page(from);
+		if (to > from)
+			tocopy = min(tocopy, to - from);
+		if (!tocopy)
+			break;
+
+		addr = rb->aux_pages[from >> PAGE_SHIFT];
+		addr += offset_in_page(from);
+
+		remainder = perf_output_copy(handle, addr, tocopy);
+		if (remainder)
+			return -EFAULT;
+
+		len += tocopy;
+		from += tocopy;
+		from &= (rb->aux_nr_pages << PAGE_SHIFT) - 1;
+	} while (to != from);
+
+	return len;
+}
+
+#define PERF_AUX_GFP	(GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY)
+
+static struct page *rb_alloc_aux_page(int node, int order)
+{
+	struct page *page;
+
+	if (order > MAX_ORDER)
+		order = MAX_ORDER;
+
+	do {
+		page = alloc_pages_node(node, PERF_AUX_GFP, order);
+	} while (!page && order--);
+
+	if (page && order) {
+		/*
+		 * Communicate the allocation size to the driver:
+		 * if we managed to secure a high-order allocation,
+		 * set its first page's private to this order;
+		 * !PagePrivate(page) means it's just a normal page.
+		 */
+		split_page(page, order);
+		SetPagePrivate(page);
+		set_page_private(page, order);
+	}
+
+	return page;
+}
+
+static void rb_free_aux_page(struct perf_buffer *rb, int idx)
+{
+	struct page *page = virt_to_page(rb->aux_pages[idx]);
+
+	ClearPagePrivate(page);
+	page->mapping = NULL;
+	__free_page(page);
+}
+
+static void __rb_free_aux(struct perf_buffer *rb)
+{
+	int pg;
+
+	/*
+	 * Should never happen, the last reference should be dropped from
+	 * perf_mmap_close() path, which first stops aux transactions (which
+	 * in turn are the atomic holders of aux_refcount) and then does the
+	 * last rb_free_aux().
+	 */
+	WARN_ON_ONCE(in_atomic());
+
+	if (rb->aux_priv) {
+		rb->free_aux(rb->aux_priv);
+		rb->free_aux = NULL;
+		rb->aux_priv = NULL;
+	}
+
+	if (rb->aux_nr_pages) {
+		for (pg = 0; pg < rb->aux_nr_pages; pg++)
+			rb_free_aux_page(rb, pg);
+
+		kfree(rb->aux_pages);
+		rb->aux_nr_pages = 0;
+	}
+}
+
+int rb_alloc_aux(struct perf_buffer *rb, struct perf_event *event,
+		 pgoff_t pgoff, int nr_pages, long watermark, int flags)
+{
+	bool overwrite = !(flags & RING_BUFFER_WRITABLE);
+	int node = (event->cpu == -1) ? -1 : cpu_to_node(event->cpu);
+	int ret = -ENOMEM, max_order;
+
+	if (!has_aux(event))
+		return -EOPNOTSUPP;
+
+	if (!overwrite) {
+		/*
+		 * Watermark defaults to half the buffer, and so does the
+		 * max_order, to aid PMU drivers in double buffering.
+		 */
+		if (!watermark)
+			watermark = nr_pages << (PAGE_SHIFT - 1);
+
+		/*
+		 * Use aux_watermark as the basis for chunking to
+		 * help PMU drivers honor the watermark.
+		 */
+		max_order = get_order(watermark);
+	} else {
+		/*
+		 * We need to start with the max_order that fits in nr_pages,
+		 * not the other way around, hence ilog2() and not get_order.
+		 */
+		max_order = ilog2(nr_pages);
+		watermark = 0;
+	}
+
+	rb->aux_pages = kcalloc_node(nr_pages, sizeof(void *), GFP_KERNEL,
+				     node);
+	if (!rb->aux_pages)
+		return -ENOMEM;
+
+	rb->free_aux = event->pmu->free_aux;
+	for (rb->aux_nr_pages = 0; rb->aux_nr_pages < nr_pages;) {
+		struct page *page;
+		int last, order;
+
+		order = min(max_order, ilog2(nr_pages - rb->aux_nr_pages));
+		page = rb_alloc_aux_page(node, order);
+		if (!page)
+			goto out;
+
+		for (last = rb->aux_nr_pages + (1 << page_private(page));
+		     last > rb->aux_nr_pages; rb->aux_nr_pages++)
+			rb->aux_pages[rb->aux_nr_pages] = page_address(page++);
+	}
+
+	/*
+	 * In overwrite mode, PMUs that don't support SG may not handle more
+	 * than one contiguous allocation, since they rely on PMI to do double
+	 * buffering. In this case, the entire buffer has to be one contiguous
+	 * chunk.
+	 */
+	if ((event->pmu->capabilities & PERF_PMU_CAP_AUX_NO_SG) &&
+	    overwrite) {
+		struct page *page = virt_to_page(rb->aux_pages[0]);
+
+		if (page_private(page) != max_order)
+			goto out;
+	}
+
+	rb->aux_priv = event->pmu->setup_aux(event, rb->aux_pages, nr_pages,
+					     overwrite);
+	if (!rb->aux_priv)
+		goto out;
+
+	ret = 0;
+
+	/*
+	 * aux_pages (and pmu driver's private data, aux_priv) will be
+	 * referenced in both producer's and consumer's contexts, thus
+	 * we keep a refcount here to make sure either of the two can
+	 * reference them safely.
+	 */
+	refcount_set(&rb->aux_refcount, 1);
+
+	rb->aux_overwrite = overwrite;
+	rb->aux_watermark = watermark;
+
+out:
+	if (!ret)
+		rb->aux_pgoff = pgoff;
+	else
+		__rb_free_aux(rb);
+
+	return ret;
+}
+
+void rb_free_aux(struct perf_buffer *rb)
+{
+	if (refcount_dec_and_test(&rb->aux_refcount))
+		__rb_free_aux(rb);
+}
+
+#ifndef CONFIG_PERF_USE_VMALLOC
+
+/*
+ * Back perf_mmap() with regular GFP_KERNEL-0 pages.
+ */
+
+static struct page *
+__perf_mmap_to_page(struct perf_buffer *rb, unsigned long pgoff)
+{
+	if (pgoff > rb->nr_pages)
+		return NULL;
+
+	if (pgoff == 0)
+		return virt_to_page(rb->user_page);
+
+	return virt_to_page(rb->data_pages[pgoff - 1]);
+}
+
+static void *perf_mmap_alloc_page(int cpu)
+{
+	struct page *page;
+	int node;
+
+	node = (cpu == -1) ? cpu : cpu_to_node(cpu);
+	page = alloc_pages_node(node, GFP_KERNEL | __GFP_ZERO, 0);
+	if (!page)
+		return NULL;
+
+	return page_address(page);
+}
+
+static void perf_mmap_free_page(void *addr)
+{
+	struct page *page = virt_to_page(addr);
+
+	page->mapping = NULL;
+	__free_page(page);
+}
+
+struct perf_buffer *rb_alloc(int nr_pages, long watermark, int cpu, int flags)
+{
+	struct perf_buffer *rb;
+	unsigned long size;
+	int i, node;
+
+	size = sizeof(struct perf_buffer);
+	size += nr_pages * sizeof(void *);
+
+	if (order_base_2(size) >= PAGE_SHIFT+MAX_ORDER)
+		goto fail;
+
+	node = (cpu == -1) ? cpu : cpu_to_node(cpu);
+	rb = kzalloc_node(size, GFP_KERNEL, node);
+	if (!rb)
+		goto fail;
+
+	rb->user_page = perf_mmap_alloc_page(cpu);
+	if (!rb->user_page)
+		goto fail_user_page;
+
+	for (i = 0; i < nr_pages; i++) {
+		rb->data_pages[i] = perf_mmap_alloc_page(cpu);
+		if (!rb->data_pages[i])
+			goto fail_data_pages;
+	}
+
+	rb->nr_pages = nr_pages;
+
+	ring_buffer_init(rb, watermark, flags);
+
+	return rb;
+
+fail_data_pages:
+	for (i--; i >= 0; i--)
+		perf_mmap_free_page(rb->data_pages[i]);
+
+	perf_mmap_free_page(rb->user_page);
+
+fail_user_page:
+	kfree(rb);
+
+fail:
+	return NULL;
+}
+
+void rb_free(struct perf_buffer *rb)
+{
+	int i;
+
+	perf_mmap_free_page(rb->user_page);
+	for (i = 0; i < rb->nr_pages; i++)
+		perf_mmap_free_page(rb->data_pages[i]);
+	kfree(rb);
+}
+
+#else
+static struct page *
+__perf_mmap_to_page(struct perf_buffer *rb, unsigned long pgoff)
+{
+	/* The '>' counts in the user page. */
+	if (pgoff > data_page_nr(rb))
+		return NULL;
+
+	return vmalloc_to_page((void *)rb->user_page + pgoff * PAGE_SIZE);
+}
+
+static void perf_mmap_unmark_page(void *addr)
+{
+	struct page *page = vmalloc_to_page(addr);
+
+	page->mapping = NULL;
+}
+
+static void rb_free_work(struct work_struct *work)
+{
+	struct perf_buffer *rb;
+	void *base;
+	int i, nr;
+
+	rb = container_of(work, struct perf_buffer, work);
+	nr = data_page_nr(rb);
+
+	base = rb->user_page;
+	/* The '<=' counts in the user page. */
+	for (i = 0; i <= nr; i++)
+		perf_mmap_unmark_page(base + (i * PAGE_SIZE));
+
+	vfree(base);
+	kfree(rb);
+}
+
+void rb_free(struct perf_buffer *rb)
+{
+	schedule_work(&rb->work);
+}
+
+struct perf_buffer *rb_alloc(int nr_pages, long watermark, int cpu, int flags)
+{
+	struct perf_buffer *rb;
+	unsigned long size;
+	void *all_buf;
+	int node;
+
+	size = sizeof(struct perf_buffer);
+	size += sizeof(void *);
+
+	node = (cpu == -1) ? cpu : cpu_to_node(cpu);
+	rb = kzalloc_node(size, GFP_KERNEL, node);
+	if (!rb)
+		goto fail;
+
+	INIT_WORK(&rb->work, rb_free_work);
+
+	all_buf = vmalloc_user((nr_pages + 1) * PAGE_SIZE);
+	if (!all_buf)
+		goto fail_all_buf;
+
+	rb->user_page = all_buf;
+	rb->data_pages[0] = all_buf + PAGE_SIZE;
+	if (nr_pages) {
+		rb->nr_pages = 1;
+		rb->page_order = ilog2(nr_pages);
+	}
+
+	ring_buffer_init(rb, watermark, flags);
+
+	return rb;
+
+fail_all_buf:
+	kfree(rb);
+
+fail:
+	return NULL;
+}
+
+#endif
+
+struct page *
+perf_mmap_to_page(struct perf_buffer *rb, unsigned long pgoff)
+{
+	if (rb->aux_nr_pages) {
+		/* above AUX space */
+		if (pgoff > rb->aux_pgoff + rb->aux_nr_pages)
+			return NULL;
+
+		/* AUX space */
+		if (pgoff >= rb->aux_pgoff) {
+			int aux_pgoff = array_index_nospec(pgoff - rb->aux_pgoff, rb->aux_nr_pages);
+			return virt_to_page(rb->aux_pages[aux_pgoff]);
+		}
+	}
+
+	return __perf_mmap_to_page(rb, pgoff);
+}