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, 672 insertions, 0 deletions

diff --git a/drivers/media/usb/pvrusb2/pvrusb2-io.c b/drivers/media/usb/pvrusb2/pvrusb2-io.c
new file mode 100644
index 000000000..675dc7153
--- /dev/null
+++ b/drivers/media/usb/pvrusb2/pvrusb2-io.c
@@ -0,0 +1,672 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ *  Copyright (C) 2005 Mike Isely <isely@pobox.com>
+ */
+
+#include "pvrusb2-io.h"
+#include "pvrusb2-debug.h"
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+
+static const char *pvr2_buffer_state_decode(enum pvr2_buffer_state);
+
+#define BUFFER_SIG 0x47653271
+
+// #define SANITY_CHECK_BUFFERS
+
+
+#ifdef SANITY_CHECK_BUFFERS
+#define BUFFER_CHECK(bp) do { \
+	if ((bp)->signature != BUFFER_SIG) { \
+		pvr2_trace(PVR2_TRACE_ERROR_LEGS, \
+		"Buffer %p is bad at %s:%d", \
+		(bp), __FILE__, __LINE__); \
+		pvr2_buffer_describe(bp, "BadSig"); \
+		BUG(); \
+	} \
+} while (0)
+#else
+#define BUFFER_CHECK(bp) do {} while (0)
+#endif
+
+struct pvr2_stream {
+	/* Buffers queued for reading */
+	struct list_head queued_list;
+	unsigned int q_count;
+	unsigned int q_bcount;
+	/* Buffers with retrieved data */
+	struct list_head ready_list;
+	unsigned int r_count;
+	unsigned int r_bcount;
+	/* Buffers available for use */
+	struct list_head idle_list;
+	unsigned int i_count;
+	unsigned int i_bcount;
+	/* Pointers to all buffers */
+	struct pvr2_buffer **buffers;
+	/* Array size of buffers */
+	unsigned int buffer_slot_count;
+	/* Total buffers actually in circulation */
+	unsigned int buffer_total_count;
+	/* Designed number of buffers to be in circulation */
+	unsigned int buffer_target_count;
+	/* Executed when ready list become non-empty */
+	pvr2_stream_callback callback_func;
+	void *callback_data;
+	/* Context for transfer endpoint */
+	struct usb_device *dev;
+	int endpoint;
+	/* Overhead for mutex enforcement */
+	spinlock_t list_lock;
+	struct mutex mutex;
+	/* Tracking state for tolerating errors */
+	unsigned int fail_count;
+	unsigned int fail_tolerance;
+
+	unsigned int buffers_processed;
+	unsigned int buffers_failed;
+	unsigned int bytes_processed;
+};
+
+struct pvr2_buffer {
+	int id;
+	int signature;
+	enum pvr2_buffer_state state;
+	void *ptr;               /* Pointer to storage area */
+	unsigned int max_count;  /* Size of storage area */
+	unsigned int used_count; /* Amount of valid data in storage area */
+	int status;              /* Transfer result status */
+	struct pvr2_stream *stream;
+	struct list_head list_overhead;
+	struct urb *purb;
+};
+
+static const char *pvr2_buffer_state_decode(enum pvr2_buffer_state st)
+{
+	switch (st) {
+	case pvr2_buffer_state_none: return "none";
+	case pvr2_buffer_state_idle: return "idle";
+	case pvr2_buffer_state_queued: return "queued";
+	case pvr2_buffer_state_ready: return "ready";
+	}
+	return "unknown";
+}
+
+#ifdef SANITY_CHECK_BUFFERS
+static void pvr2_buffer_describe(struct pvr2_buffer *bp, const char *msg)
+{
+	pvr2_trace(PVR2_TRACE_INFO,
+		   "buffer%s%s %p state=%s id=%d status=%d stream=%p purb=%p sig=0x%x",
+		   (msg ? " " : ""),
+		   (msg ? msg : ""),
+		   bp,
+		   (bp ? pvr2_buffer_state_decode(bp->state) : "(invalid)"),
+		   (bp ? bp->id : 0),
+		   (bp ? bp->status : 0),
+		   (bp ? bp->stream : NULL),
+		   (bp ? bp->purb : NULL),
+		   (bp ? bp->signature : 0));
+}
+#endif  /*  SANITY_CHECK_BUFFERS  */
+
+static void pvr2_buffer_remove(struct pvr2_buffer *bp)
+{
+	unsigned int *cnt;
+	unsigned int *bcnt;
+	unsigned int ccnt;
+	struct pvr2_stream *sp = bp->stream;
+	switch (bp->state) {
+	case pvr2_buffer_state_idle:
+		cnt = &sp->i_count;
+		bcnt = &sp->i_bcount;
+		ccnt = bp->max_count;
+		break;
+	case pvr2_buffer_state_queued:
+		cnt = &sp->q_count;
+		bcnt = &sp->q_bcount;
+		ccnt = bp->max_count;
+		break;
+	case pvr2_buffer_state_ready:
+		cnt = &sp->r_count;
+		bcnt = &sp->r_bcount;
+		ccnt = bp->used_count;
+		break;
+	default:
+		return;
+	}
+	list_del_init(&bp->list_overhead);
+	(*cnt)--;
+	(*bcnt) -= ccnt;
+	pvr2_trace(PVR2_TRACE_BUF_FLOW,
+		   "/*---TRACE_FLOW---*/ bufferPool	%8s dec cap=%07d cnt=%02d",
+		   pvr2_buffer_state_decode(bp->state), *bcnt, *cnt);
+	bp->state = pvr2_buffer_state_none;
+}
+
+static void pvr2_buffer_set_none(struct pvr2_buffer *bp)
+{
+	unsigned long irq_flags;
+	struct pvr2_stream *sp;
+	BUFFER_CHECK(bp);
+	sp = bp->stream;
+	pvr2_trace(PVR2_TRACE_BUF_FLOW,
+		   "/*---TRACE_FLOW---*/ bufferState    %p %6s --> %6s",
+		   bp,
+		   pvr2_buffer_state_decode(bp->state),
+		   pvr2_buffer_state_decode(pvr2_buffer_state_none));
+	spin_lock_irqsave(&sp->list_lock, irq_flags);
+	pvr2_buffer_remove(bp);
+	spin_unlock_irqrestore(&sp->list_lock, irq_flags);
+}
+
+static int pvr2_buffer_set_ready(struct pvr2_buffer *bp)
+{
+	int fl;
+	unsigned long irq_flags;
+	struct pvr2_stream *sp;
+	BUFFER_CHECK(bp);
+	sp = bp->stream;
+	pvr2_trace(PVR2_TRACE_BUF_FLOW,
+		   "/*---TRACE_FLOW---*/ bufferState    %p %6s --> %6s",
+		   bp,
+		   pvr2_buffer_state_decode(bp->state),
+		   pvr2_buffer_state_decode(pvr2_buffer_state_ready));
+	spin_lock_irqsave(&sp->list_lock, irq_flags);
+	fl = (sp->r_count == 0);
+	pvr2_buffer_remove(bp);
+	list_add_tail(&bp->list_overhead, &sp->ready_list);
+	bp->state = pvr2_buffer_state_ready;
+	(sp->r_count)++;
+	sp->r_bcount += bp->used_count;
+	pvr2_trace(PVR2_TRACE_BUF_FLOW,
+		   "/*---TRACE_FLOW---*/ bufferPool	%8s inc cap=%07d cnt=%02d",
+		   pvr2_buffer_state_decode(bp->state),
+		   sp->r_bcount, sp->r_count);
+	spin_unlock_irqrestore(&sp->list_lock, irq_flags);
+	return fl;
+}
+
+static void pvr2_buffer_set_idle(struct pvr2_buffer *bp)
+{
+	unsigned long irq_flags;
+	struct pvr2_stream *sp;
+	BUFFER_CHECK(bp);
+	sp = bp->stream;
+	pvr2_trace(PVR2_TRACE_BUF_FLOW,
+		   "/*---TRACE_FLOW---*/ bufferState    %p %6s --> %6s",
+		   bp,
+		   pvr2_buffer_state_decode(bp->state),
+		   pvr2_buffer_state_decode(pvr2_buffer_state_idle));
+	spin_lock_irqsave(&sp->list_lock, irq_flags);
+	pvr2_buffer_remove(bp);
+	list_add_tail(&bp->list_overhead, &sp->idle_list);
+	bp->state = pvr2_buffer_state_idle;
+	(sp->i_count)++;
+	sp->i_bcount += bp->max_count;
+	pvr2_trace(PVR2_TRACE_BUF_FLOW,
+		   "/*---TRACE_FLOW---*/ bufferPool	%8s inc cap=%07d cnt=%02d",
+		   pvr2_buffer_state_decode(bp->state),
+		   sp->i_bcount, sp->i_count);
+	spin_unlock_irqrestore(&sp->list_lock, irq_flags);
+}
+
+static void pvr2_buffer_set_queued(struct pvr2_buffer *bp)
+{
+	unsigned long irq_flags;
+	struct pvr2_stream *sp;
+	BUFFER_CHECK(bp);
+	sp = bp->stream;
+	pvr2_trace(PVR2_TRACE_BUF_FLOW,
+		   "/*---TRACE_FLOW---*/ bufferState    %p %6s --> %6s",
+		   bp,
+		   pvr2_buffer_state_decode(bp->state),
+		   pvr2_buffer_state_decode(pvr2_buffer_state_queued));
+	spin_lock_irqsave(&sp->list_lock, irq_flags);
+	pvr2_buffer_remove(bp);
+	list_add_tail(&bp->list_overhead, &sp->queued_list);
+	bp->state = pvr2_buffer_state_queued;
+	(sp->q_count)++;
+	sp->q_bcount += bp->max_count;
+	pvr2_trace(PVR2_TRACE_BUF_FLOW,
+		   "/*---TRACE_FLOW---*/ bufferPool	%8s inc cap=%07d cnt=%02d",
+		   pvr2_buffer_state_decode(bp->state),
+		   sp->q_bcount, sp->q_count);
+	spin_unlock_irqrestore(&sp->list_lock, irq_flags);
+}
+
+static void pvr2_buffer_wipe(struct pvr2_buffer *bp)
+{
+	if (bp->state == pvr2_buffer_state_queued) {
+		usb_kill_urb(bp->purb);
+	}
+}
+
+static int pvr2_buffer_init(struct pvr2_buffer *bp,
+			    struct pvr2_stream *sp,
+			    unsigned int id)
+{
+	memset(bp, 0, sizeof(*bp));
+	bp->signature = BUFFER_SIG;
+	bp->id = id;
+	pvr2_trace(PVR2_TRACE_BUF_POOL,
+		   "/*---TRACE_FLOW---*/ bufferInit     %p stream=%p", bp, sp);
+	bp->stream = sp;
+	bp->state = pvr2_buffer_state_none;
+	INIT_LIST_HEAD(&bp->list_overhead);
+	bp->purb = usb_alloc_urb(0, GFP_KERNEL);
+	if (! bp->purb) return -ENOMEM;
+#ifdef SANITY_CHECK_BUFFERS
+	pvr2_buffer_describe(bp, "create");
+#endif
+	return 0;
+}
+
+static void pvr2_buffer_done(struct pvr2_buffer *bp)
+{
+#ifdef SANITY_CHECK_BUFFERS
+	pvr2_buffer_describe(bp, "delete");
+#endif
+	pvr2_buffer_wipe(bp);
+	pvr2_buffer_set_none(bp);
+	bp->signature = 0;
+	bp->stream = NULL;
+	usb_free_urb(bp->purb);
+	pvr2_trace(PVR2_TRACE_BUF_POOL, "/*---TRACE_FLOW---*/ bufferDone     %p",
+		   bp);
+}
+
+static int pvr2_stream_buffer_count(struct pvr2_stream *sp, unsigned int cnt)
+{
+	int ret;
+	unsigned int scnt;
+
+	/* Allocate buffers pointer array in multiples of 32 entries */
+	if (cnt == sp->buffer_total_count) return 0;
+
+	pvr2_trace(PVR2_TRACE_BUF_POOL,
+		   "/*---TRACE_FLOW---*/ poolResize	stream=%p cur=%d adj=%+d",
+		   sp,
+		   sp->buffer_total_count,
+		   cnt-sp->buffer_total_count);
+
+	scnt = cnt & ~0x1f;
+	if (cnt > scnt) scnt += 0x20;
+
+	if (cnt > sp->buffer_total_count) {
+		if (scnt > sp->buffer_slot_count) {
+			struct pvr2_buffer **nb;
+
+			nb = kmalloc_array(scnt, sizeof(*nb), GFP_KERNEL);
+			if (!nb) return -ENOMEM;
+			if (sp->buffer_slot_count) {
+				memcpy(nb, sp->buffers,
+				       sp->buffer_slot_count * sizeof(*nb));
+				kfree(sp->buffers);
+			}
+			sp->buffers = nb;
+			sp->buffer_slot_count = scnt;
+		}
+		while (sp->buffer_total_count < cnt) {
+			struct pvr2_buffer *bp;
+			bp = kmalloc(sizeof(*bp), GFP_KERNEL);
+			if (!bp) return -ENOMEM;
+			ret = pvr2_buffer_init(bp, sp, sp->buffer_total_count);
+			if (ret) {
+				kfree(bp);
+				return -ENOMEM;
+			}
+			sp->buffers[sp->buffer_total_count] = bp;
+			(sp->buffer_total_count)++;
+			pvr2_buffer_set_idle(bp);
+		}
+	} else {
+		while (sp->buffer_total_count > cnt) {
+			struct pvr2_buffer *bp;
+			bp = sp->buffers[sp->buffer_total_count - 1];
+			/* Paranoia */
+			sp->buffers[sp->buffer_total_count - 1] = NULL;
+			(sp->buffer_total_count)--;
+			pvr2_buffer_done(bp);
+			kfree(bp);
+		}
+		if (scnt < sp->buffer_slot_count) {
+			struct pvr2_buffer **nb = NULL;
+			if (scnt) {
+				nb = kmemdup(sp->buffers, scnt * sizeof(*nb),
+					     GFP_KERNEL);
+				if (!nb) return -ENOMEM;
+			}
+			kfree(sp->buffers);
+			sp->buffers = nb;
+			sp->buffer_slot_count = scnt;
+		}
+	}
+	return 0;
+}
+
+static int pvr2_stream_achieve_buffer_count(struct pvr2_stream *sp)
+{
+	struct pvr2_buffer *bp;
+	unsigned int cnt;
+
+	if (sp->buffer_total_count == sp->buffer_target_count) return 0;
+
+	pvr2_trace(PVR2_TRACE_BUF_POOL,
+		   "/*---TRACE_FLOW---*/ poolCheck	stream=%p cur=%d tgt=%d",
+		   sp, sp->buffer_total_count, sp->buffer_target_count);
+
+	if (sp->buffer_total_count < sp->buffer_target_count) {
+		return pvr2_stream_buffer_count(sp, sp->buffer_target_count);
+	}
+
+	cnt = 0;
+	while ((sp->buffer_total_count - cnt) > sp->buffer_target_count) {
+		bp = sp->buffers[sp->buffer_total_count - (cnt + 1)];
+		if (bp->state != pvr2_buffer_state_idle) break;
+		cnt++;
+	}
+	if (cnt) {
+		pvr2_stream_buffer_count(sp, sp->buffer_total_count - cnt);
+	}
+
+	return 0;
+}
+
+static void pvr2_stream_internal_flush(struct pvr2_stream *sp)
+{
+	struct list_head *lp;
+	struct pvr2_buffer *bp1;
+	while ((lp = sp->queued_list.next) != &sp->queued_list) {
+		bp1 = list_entry(lp, struct pvr2_buffer, list_overhead);
+		pvr2_buffer_wipe(bp1);
+		/* At this point, we should be guaranteed that no
+		   completion callback may happen on this buffer.  But it's
+		   possible that it might have completed after we noticed
+		   it but before we wiped it.  So double check its status
+		   here first. */
+		if (bp1->state != pvr2_buffer_state_queued) continue;
+		pvr2_buffer_set_idle(bp1);
+	}
+	if (sp->buffer_total_count != sp->buffer_target_count) {
+		pvr2_stream_achieve_buffer_count(sp);
+	}
+}
+
+static void pvr2_stream_init(struct pvr2_stream *sp)
+{
+	spin_lock_init(&sp->list_lock);
+	mutex_init(&sp->mutex);
+	INIT_LIST_HEAD(&sp->queued_list);
+	INIT_LIST_HEAD(&sp->ready_list);
+	INIT_LIST_HEAD(&sp->idle_list);
+}
+
+static void pvr2_stream_done(struct pvr2_stream *sp)
+{
+	mutex_lock(&sp->mutex); do {
+		pvr2_stream_internal_flush(sp);
+		pvr2_stream_buffer_count(sp, 0);
+	} while (0); mutex_unlock(&sp->mutex);
+}
+
+static void buffer_complete(struct urb *urb)
+{
+	struct pvr2_buffer *bp = urb->context;
+	struct pvr2_stream *sp;
+	unsigned long irq_flags;
+	BUFFER_CHECK(bp);
+	sp = bp->stream;
+	bp->used_count = 0;
+	bp->status = 0;
+	pvr2_trace(PVR2_TRACE_BUF_FLOW,
+		   "/*---TRACE_FLOW---*/ bufferComplete %p stat=%d cnt=%d",
+		   bp, urb->status, urb->actual_length);
+	spin_lock_irqsave(&sp->list_lock, irq_flags);
+	if ((!(urb->status)) ||
+	    (urb->status == -ENOENT) ||
+	    (urb->status == -ECONNRESET) ||
+	    (urb->status == -ESHUTDOWN)) {
+		(sp->buffers_processed)++;
+		sp->bytes_processed += urb->actual_length;
+		bp->used_count = urb->actual_length;
+		if (sp->fail_count) {
+			pvr2_trace(PVR2_TRACE_TOLERANCE,
+				   "stream %p transfer ok - fail count reset",
+				   sp);
+			sp->fail_count = 0;
+		}
+	} else if (sp->fail_count < sp->fail_tolerance) {
+		// We can tolerate this error, because we're below the
+		// threshold...
+		(sp->fail_count)++;
+		(sp->buffers_failed)++;
+		pvr2_trace(PVR2_TRACE_TOLERANCE,
+			   "stream %p ignoring error %d - fail count increased to %u",
+			   sp, urb->status, sp->fail_count);
+	} else {
+		(sp->buffers_failed)++;
+		bp->status = urb->status;
+	}
+	spin_unlock_irqrestore(&sp->list_lock, irq_flags);
+	pvr2_buffer_set_ready(bp);
+	if (sp->callback_func) {
+		sp->callback_func(sp->callback_data);
+	}
+}
+
+struct pvr2_stream *pvr2_stream_create(void)
+{
+	struct pvr2_stream *sp;
+	sp = kzalloc(sizeof(*sp), GFP_KERNEL);
+	if (!sp) return sp;
+	pvr2_trace(PVR2_TRACE_INIT, "pvr2_stream_create: sp=%p", sp);
+	pvr2_stream_init(sp);
+	return sp;
+}
+
+void pvr2_stream_destroy(struct pvr2_stream *sp)
+{
+	if (!sp) return;
+	pvr2_trace(PVR2_TRACE_INIT, "pvr2_stream_destroy: sp=%p", sp);
+	pvr2_stream_done(sp);
+	kfree(sp);
+}
+
+void pvr2_stream_setup(struct pvr2_stream *sp,
+		       struct usb_device *dev,
+		       int endpoint,
+		       unsigned int tolerance)
+{
+	mutex_lock(&sp->mutex); do {
+		pvr2_stream_internal_flush(sp);
+		sp->dev = dev;
+		sp->endpoint = endpoint;
+		sp->fail_tolerance = tolerance;
+	} while (0); mutex_unlock(&sp->mutex);
+}
+
+void pvr2_stream_set_callback(struct pvr2_stream *sp,
+			      pvr2_stream_callback func,
+			      void *data)
+{
+	unsigned long irq_flags;
+	mutex_lock(&sp->mutex);
+	do {
+		spin_lock_irqsave(&sp->list_lock, irq_flags);
+		sp->callback_data = data;
+		sp->callback_func = func;
+		spin_unlock_irqrestore(&sp->list_lock, irq_flags);
+	} while (0);
+	mutex_unlock(&sp->mutex);
+}
+
+void pvr2_stream_get_stats(struct pvr2_stream *sp,
+			   struct pvr2_stream_stats *stats,
+			   int zero_counts)
+{
+	unsigned long irq_flags;
+	spin_lock_irqsave(&sp->list_lock, irq_flags);
+	if (stats) {
+		stats->buffers_in_queue = sp->q_count;
+		stats->buffers_in_idle = sp->i_count;
+		stats->buffers_in_ready = sp->r_count;
+		stats->buffers_processed = sp->buffers_processed;
+		stats->buffers_failed = sp->buffers_failed;
+		stats->bytes_processed = sp->bytes_processed;
+	}
+	if (zero_counts) {
+		sp->buffers_processed = 0;
+		sp->buffers_failed = 0;
+		sp->bytes_processed = 0;
+	}
+	spin_unlock_irqrestore(&sp->list_lock, irq_flags);
+}
+
+/* Query / set the nominal buffer count */
+int pvr2_stream_get_buffer_count(struct pvr2_stream *sp)
+{
+	return sp->buffer_target_count;
+}
+
+int pvr2_stream_set_buffer_count(struct pvr2_stream *sp, unsigned int cnt)
+{
+	int ret;
+	if (sp->buffer_target_count == cnt) return 0;
+	mutex_lock(&sp->mutex);
+	do {
+		sp->buffer_target_count = cnt;
+		ret = pvr2_stream_achieve_buffer_count(sp);
+	} while (0);
+	mutex_unlock(&sp->mutex);
+	return ret;
+}
+
+struct pvr2_buffer *pvr2_stream_get_idle_buffer(struct pvr2_stream *sp)
+{
+	struct list_head *lp = sp->idle_list.next;
+	if (lp == &sp->idle_list) return NULL;
+	return list_entry(lp, struct pvr2_buffer, list_overhead);
+}
+
+struct pvr2_buffer *pvr2_stream_get_ready_buffer(struct pvr2_stream *sp)
+{
+	struct list_head *lp = sp->ready_list.next;
+	if (lp == &sp->ready_list) return NULL;
+	return list_entry(lp, struct pvr2_buffer, list_overhead);
+}
+
+struct pvr2_buffer *pvr2_stream_get_buffer(struct pvr2_stream *sp, int id)
+{
+	if (id < 0) return NULL;
+	if (id >= sp->buffer_total_count) return NULL;
+	return sp->buffers[id];
+}
+
+int pvr2_stream_get_ready_count(struct pvr2_stream *sp)
+{
+	return sp->r_count;
+}
+
+void pvr2_stream_kill(struct pvr2_stream *sp)
+{
+	struct pvr2_buffer *bp;
+	mutex_lock(&sp->mutex);
+	do {
+		pvr2_stream_internal_flush(sp);
+		while ((bp = pvr2_stream_get_ready_buffer(sp)) != NULL) {
+			pvr2_buffer_set_idle(bp);
+		}
+		if (sp->buffer_total_count != sp->buffer_target_count) {
+			pvr2_stream_achieve_buffer_count(sp);
+		}
+	} while (0);
+	mutex_unlock(&sp->mutex);
+}
+
+int pvr2_buffer_queue(struct pvr2_buffer *bp)
+{
+#undef SEED_BUFFER
+#ifdef SEED_BUFFER
+	unsigned int idx;
+	unsigned int val;
+#endif
+	int ret = 0;
+	struct pvr2_stream *sp;
+	if (!bp) return -EINVAL;
+	sp = bp->stream;
+	mutex_lock(&sp->mutex);
+	do {
+		pvr2_buffer_wipe(bp);
+		if (!sp->dev) {
+			ret = -EIO;
+			break;
+		}
+		pvr2_buffer_set_queued(bp);
+#ifdef SEED_BUFFER
+		for (idx = 0; idx < (bp->max_count) / 4; idx++) {
+			val = bp->id << 24;
+			val |= idx;
+			((unsigned int *)(bp->ptr))[idx] = val;
+		}
+#endif
+		bp->status = -EINPROGRESS;
+		usb_fill_bulk_urb(bp->purb,      // struct urb *urb
+				  sp->dev,       // struct usb_device *dev
+				  // endpoint (below)
+				  usb_rcvbulkpipe(sp->dev, sp->endpoint),
+				  bp->ptr,       // void *transfer_buffer
+				  bp->max_count, // int buffer_length
+				  buffer_complete,
+				  bp);
+		usb_submit_urb(bp->purb, GFP_KERNEL);
+	} while (0);
+	mutex_unlock(&sp->mutex);
+	return ret;
+}
+
+int pvr2_buffer_set_buffer(struct pvr2_buffer *bp, void *ptr, unsigned int cnt)
+{
+	int ret = 0;
+	unsigned long irq_flags;
+	struct pvr2_stream *sp;
+	if (!bp) return -EINVAL;
+	sp = bp->stream;
+	mutex_lock(&sp->mutex);
+	do {
+		spin_lock_irqsave(&sp->list_lock, irq_flags);
+		if (bp->state != pvr2_buffer_state_idle) {
+			ret = -EPERM;
+		} else {
+			bp->ptr = ptr;
+			bp->stream->i_bcount -= bp->max_count;
+			bp->max_count = cnt;
+			bp->stream->i_bcount += bp->max_count;
+			pvr2_trace(PVR2_TRACE_BUF_FLOW,
+				   "/*---TRACE_FLOW---*/ bufferPool	%8s cap cap=%07d cnt=%02d",
+				   pvr2_buffer_state_decode(
+					   pvr2_buffer_state_idle),
+				   bp->stream->i_bcount, bp->stream->i_count);
+		}
+		spin_unlock_irqrestore(&sp->list_lock, irq_flags);
+	} while (0);
+	mutex_unlock(&sp->mutex);
+	return ret;
+}
+
+unsigned int pvr2_buffer_get_count(struct pvr2_buffer *bp)
+{
+	return bp->used_count;
+}
+
+int pvr2_buffer_get_status(struct pvr2_buffer *bp)
+{
+	return bp->status;
+}
+
+int pvr2_buffer_get_id(struct pvr2_buffer *bp)
+{
+	return bp->id;
+}