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, 774 insertions, 0 deletions

diff --git a/sound/core/seq/seq_queue.c b/sound/core/seq/seq_queue.c
new file mode 100644
index 000000000..bc933104c
--- /dev/null
+++ b/sound/core/seq/seq_queue.c
@@ -0,0 +1,774 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   ALSA sequencer Timing queue handling
+ *   Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
+ *
+ * MAJOR CHANGES
+ *   Nov. 13, 1999	Takashi Iwai <iwai@ww.uni-erlangen.de>
+ *     - Queues are allocated dynamically via ioctl.
+ *     - When owner client is deleted, all owned queues are deleted, too.
+ *     - Owner of unlocked queue is kept unmodified even if it is
+ *	 manipulated by other clients.
+ *     - Owner field in SET_QUEUE_OWNER ioctl must be identical with the
+ *       caller client.  i.e. Changing owner to a third client is not
+ *       allowed.
+ *
+ *  Aug. 30, 2000	Takashi Iwai
+ *     - Queues are managed in static array again, but with better way.
+ *       The API itself is identical.
+ *     - The queue is locked when struct snd_seq_queue pointer is returned via
+ *       queueptr().  This pointer *MUST* be released afterward by
+ *       queuefree(ptr).
+ *     - Addition of experimental sync support.
+ */
+
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <sound/core.h>
+
+#include "seq_memory.h"
+#include "seq_queue.h"
+#include "seq_clientmgr.h"
+#include "seq_fifo.h"
+#include "seq_timer.h"
+#include "seq_info.h"
+
+/* list of allocated queues */
+static struct snd_seq_queue *queue_list[SNDRV_SEQ_MAX_QUEUES];
+static DEFINE_SPINLOCK(queue_list_lock);
+/* number of queues allocated */
+static int num_queues;
+
+int snd_seq_queue_get_cur_queues(void)
+{
+	return num_queues;
+}
+
+/*----------------------------------------------------------------*/
+
+/* assign queue id and insert to list */
+static int queue_list_add(struct snd_seq_queue *q)
+{
+	int i;
+	unsigned long flags;
+
+	spin_lock_irqsave(&queue_list_lock, flags);
+	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
+		if (! queue_list[i]) {
+			queue_list[i] = q;
+			q->queue = i;
+			num_queues++;
+			spin_unlock_irqrestore(&queue_list_lock, flags);
+			return i;
+		}
+	}
+	spin_unlock_irqrestore(&queue_list_lock, flags);
+	return -1;
+}
+
+static struct snd_seq_queue *queue_list_remove(int id, int client)
+{
+	struct snd_seq_queue *q;
+	unsigned long flags;
+
+	spin_lock_irqsave(&queue_list_lock, flags);
+	q = queue_list[id];
+	if (q) {
+		spin_lock(&q->owner_lock);
+		if (q->owner == client) {
+			/* found */
+			q->klocked = 1;
+			spin_unlock(&q->owner_lock);
+			queue_list[id] = NULL;
+			num_queues--;
+			spin_unlock_irqrestore(&queue_list_lock, flags);
+			return q;
+		}
+		spin_unlock(&q->owner_lock);
+	}
+	spin_unlock_irqrestore(&queue_list_lock, flags);
+	return NULL;
+}
+
+/*----------------------------------------------------------------*/
+
+/* create new queue (constructor) */
+static struct snd_seq_queue *queue_new(int owner, int locked)
+{
+	struct snd_seq_queue *q;
+
+	q = kzalloc(sizeof(*q), GFP_KERNEL);
+	if (!q)
+		return NULL;
+
+	spin_lock_init(&q->owner_lock);
+	spin_lock_init(&q->check_lock);
+	mutex_init(&q->timer_mutex);
+	snd_use_lock_init(&q->use_lock);
+	q->queue = -1;
+
+	q->tickq = snd_seq_prioq_new();
+	q->timeq = snd_seq_prioq_new();
+	q->timer = snd_seq_timer_new();
+	if (q->tickq == NULL || q->timeq == NULL || q->timer == NULL) {
+		snd_seq_prioq_delete(&q->tickq);
+		snd_seq_prioq_delete(&q->timeq);
+		snd_seq_timer_delete(&q->timer);
+		kfree(q);
+		return NULL;
+	}
+
+	q->owner = owner;
+	q->locked = locked;
+	q->klocked = 0;
+
+	return q;
+}
+
+/* delete queue (destructor) */
+static void queue_delete(struct snd_seq_queue *q)
+{
+	/* stop and release the timer */
+	mutex_lock(&q->timer_mutex);
+	snd_seq_timer_stop(q->timer);
+	snd_seq_timer_close(q);
+	mutex_unlock(&q->timer_mutex);
+	/* wait until access free */
+	snd_use_lock_sync(&q->use_lock);
+	/* release resources... */
+	snd_seq_prioq_delete(&q->tickq);
+	snd_seq_prioq_delete(&q->timeq);
+	snd_seq_timer_delete(&q->timer);
+
+	kfree(q);
+}
+
+
+/*----------------------------------------------------------------*/
+
+/* delete all existing queues */
+void snd_seq_queues_delete(void)
+{
+	int i;
+
+	/* clear list */
+	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
+		if (queue_list[i])
+			queue_delete(queue_list[i]);
+	}
+}
+
+static void queue_use(struct snd_seq_queue *queue, int client, int use);
+
+/* allocate a new queue -
+ * return pointer to new queue or ERR_PTR(-errno) for error
+ * The new queue's use_lock is set to 1. It is the caller's responsibility to
+ * call snd_use_lock_free(&q->use_lock).
+ */
+struct snd_seq_queue *snd_seq_queue_alloc(int client, int locked, unsigned int info_flags)
+{
+	struct snd_seq_queue *q;
+
+	q = queue_new(client, locked);
+	if (q == NULL)
+		return ERR_PTR(-ENOMEM);
+	q->info_flags = info_flags;
+	queue_use(q, client, 1);
+	snd_use_lock_use(&q->use_lock);
+	if (queue_list_add(q) < 0) {
+		snd_use_lock_free(&q->use_lock);
+		queue_delete(q);
+		return ERR_PTR(-ENOMEM);
+	}
+	return q;
+}
+
+/* delete a queue - queue must be owned by the client */
+int snd_seq_queue_delete(int client, int queueid)
+{
+	struct snd_seq_queue *q;
+
+	if (queueid < 0 || queueid >= SNDRV_SEQ_MAX_QUEUES)
+		return -EINVAL;
+	q = queue_list_remove(queueid, client);
+	if (q == NULL)
+		return -EINVAL;
+	queue_delete(q);
+
+	return 0;
+}
+
+
+/* return pointer to queue structure for specified id */
+struct snd_seq_queue *queueptr(int queueid)
+{
+	struct snd_seq_queue *q;
+	unsigned long flags;
+
+	if (queueid < 0 || queueid >= SNDRV_SEQ_MAX_QUEUES)
+		return NULL;
+	spin_lock_irqsave(&queue_list_lock, flags);
+	q = queue_list[queueid];
+	if (q)
+		snd_use_lock_use(&q->use_lock);
+	spin_unlock_irqrestore(&queue_list_lock, flags);
+	return q;
+}
+
+/* return the (first) queue matching with the specified name */
+struct snd_seq_queue *snd_seq_queue_find_name(char *name)
+{
+	int i;
+	struct snd_seq_queue *q;
+
+	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
+		q = queueptr(i);
+		if (q) {
+			if (strncmp(q->name, name, sizeof(q->name)) == 0)
+				return q;
+			queuefree(q);
+		}
+	}
+	return NULL;
+}
+
+
+/* -------------------------------------------------------- */
+
+#define MAX_CELL_PROCESSES_IN_QUEUE	1000
+
+void snd_seq_check_queue(struct snd_seq_queue *q, int atomic, int hop)
+{
+	unsigned long flags;
+	struct snd_seq_event_cell *cell;
+	snd_seq_tick_time_t cur_tick;
+	snd_seq_real_time_t cur_time;
+	int processed = 0;
+
+	if (q == NULL)
+		return;
+
+	/* make this function non-reentrant */
+	spin_lock_irqsave(&q->check_lock, flags);
+	if (q->check_blocked) {
+		q->check_again = 1;
+		spin_unlock_irqrestore(&q->check_lock, flags);
+		return;		/* other thread is already checking queues */
+	}
+	q->check_blocked = 1;
+	spin_unlock_irqrestore(&q->check_lock, flags);
+
+      __again:
+	/* Process tick queue... */
+	cur_tick = snd_seq_timer_get_cur_tick(q->timer);
+	for (;;) {
+		cell = snd_seq_prioq_cell_out(q->tickq, &cur_tick);
+		if (!cell)
+			break;
+		snd_seq_dispatch_event(cell, atomic, hop);
+		if (++processed >= MAX_CELL_PROCESSES_IN_QUEUE)
+			goto out; /* the rest processed at the next batch */
+	}
+
+	/* Process time queue... */
+	cur_time = snd_seq_timer_get_cur_time(q->timer, false);
+	for (;;) {
+		cell = snd_seq_prioq_cell_out(q->timeq, &cur_time);
+		if (!cell)
+			break;
+		snd_seq_dispatch_event(cell, atomic, hop);
+		if (++processed >= MAX_CELL_PROCESSES_IN_QUEUE)
+			goto out; /* the rest processed at the next batch */
+	}
+
+ out:
+	/* free lock */
+	spin_lock_irqsave(&q->check_lock, flags);
+	if (q->check_again) {
+		q->check_again = 0;
+		if (processed < MAX_CELL_PROCESSES_IN_QUEUE) {
+			spin_unlock_irqrestore(&q->check_lock, flags);
+			goto __again;
+		}
+	}
+	q->check_blocked = 0;
+	spin_unlock_irqrestore(&q->check_lock, flags);
+}
+
+
+/* enqueue a event to singe queue */
+int snd_seq_enqueue_event(struct snd_seq_event_cell *cell, int atomic, int hop)
+{
+	int dest, err;
+	struct snd_seq_queue *q;
+
+	if (snd_BUG_ON(!cell))
+		return -EINVAL;
+	dest = cell->event.queue;	/* destination queue */
+	q = queueptr(dest);
+	if (q == NULL)
+		return -EINVAL;
+	/* handle relative time stamps, convert them into absolute */
+	if ((cell->event.flags & SNDRV_SEQ_TIME_MODE_MASK) == SNDRV_SEQ_TIME_MODE_REL) {
+		switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
+		case SNDRV_SEQ_TIME_STAMP_TICK:
+			cell->event.time.tick += q->timer->tick.cur_tick;
+			break;
+
+		case SNDRV_SEQ_TIME_STAMP_REAL:
+			snd_seq_inc_real_time(&cell->event.time.time,
+					      &q->timer->cur_time);
+			break;
+		}
+		cell->event.flags &= ~SNDRV_SEQ_TIME_MODE_MASK;
+		cell->event.flags |= SNDRV_SEQ_TIME_MODE_ABS;
+	}
+	/* enqueue event in the real-time or midi queue */
+	switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
+	case SNDRV_SEQ_TIME_STAMP_TICK:
+		err = snd_seq_prioq_cell_in(q->tickq, cell);
+		break;
+
+	case SNDRV_SEQ_TIME_STAMP_REAL:
+	default:
+		err = snd_seq_prioq_cell_in(q->timeq, cell);
+		break;
+	}
+
+	if (err < 0) {
+		queuefree(q); /* unlock */
+		return err;
+	}
+
+	/* trigger dispatching */
+	snd_seq_check_queue(q, atomic, hop);
+
+	queuefree(q); /* unlock */
+
+	return 0;
+}
+
+
+/*----------------------------------------------------------------*/
+
+static inline int check_access(struct snd_seq_queue *q, int client)
+{
+	return (q->owner == client) || (!q->locked && !q->klocked);
+}
+
+/* check if the client has permission to modify queue parameters.
+ * if it does, lock the queue
+ */
+static int queue_access_lock(struct snd_seq_queue *q, int client)
+{
+	unsigned long flags;
+	int access_ok;
+	
+	spin_lock_irqsave(&q->owner_lock, flags);
+	access_ok = check_access(q, client);
+	if (access_ok)
+		q->klocked = 1;
+	spin_unlock_irqrestore(&q->owner_lock, flags);
+	return access_ok;
+}
+
+/* unlock the queue */
+static inline void queue_access_unlock(struct snd_seq_queue *q)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&q->owner_lock, flags);
+	q->klocked = 0;
+	spin_unlock_irqrestore(&q->owner_lock, flags);
+}
+
+/* exported - only checking permission */
+int snd_seq_queue_check_access(int queueid, int client)
+{
+	struct snd_seq_queue *q = queueptr(queueid);
+	int access_ok;
+	unsigned long flags;
+
+	if (! q)
+		return 0;
+	spin_lock_irqsave(&q->owner_lock, flags);
+	access_ok = check_access(q, client);
+	spin_unlock_irqrestore(&q->owner_lock, flags);
+	queuefree(q);
+	return access_ok;
+}
+
+/*----------------------------------------------------------------*/
+
+/*
+ * change queue's owner and permission
+ */
+int snd_seq_queue_set_owner(int queueid, int client, int locked)
+{
+	struct snd_seq_queue *q = queueptr(queueid);
+	unsigned long flags;
+
+	if (q == NULL)
+		return -EINVAL;
+
+	if (! queue_access_lock(q, client)) {
+		queuefree(q);
+		return -EPERM;
+	}
+
+	spin_lock_irqsave(&q->owner_lock, flags);
+	q->locked = locked ? 1 : 0;
+	q->owner = client;
+	spin_unlock_irqrestore(&q->owner_lock, flags);
+	queue_access_unlock(q);
+	queuefree(q);
+
+	return 0;
+}
+
+
+/*----------------------------------------------------------------*/
+
+/* open timer -
+ * q->use mutex should be down before calling this function to avoid
+ * confliction with snd_seq_queue_use()
+ */
+int snd_seq_queue_timer_open(int queueid)
+{
+	int result = 0;
+	struct snd_seq_queue *queue;
+	struct snd_seq_timer *tmr;
+
+	queue = queueptr(queueid);
+	if (queue == NULL)
+		return -EINVAL;
+	tmr = queue->timer;
+	result = snd_seq_timer_open(queue);
+	if (result < 0) {
+		snd_seq_timer_defaults(tmr);
+		result = snd_seq_timer_open(queue);
+	}
+	queuefree(queue);
+	return result;
+}
+
+/* close timer -
+ * q->use mutex should be down before calling this function
+ */
+int snd_seq_queue_timer_close(int queueid)
+{
+	struct snd_seq_queue *queue;
+	int result = 0;
+
+	queue = queueptr(queueid);
+	if (queue == NULL)
+		return -EINVAL;
+	snd_seq_timer_close(queue);
+	queuefree(queue);
+	return result;
+}
+
+/* change queue tempo and ppq */
+int snd_seq_queue_timer_set_tempo(int queueid, int client,
+				  struct snd_seq_queue_tempo *info)
+{
+	struct snd_seq_queue *q = queueptr(queueid);
+	int result;
+
+	if (q == NULL)
+		return -EINVAL;
+	if (! queue_access_lock(q, client)) {
+		queuefree(q);
+		return -EPERM;
+	}
+
+	result = snd_seq_timer_set_tempo_ppq(q->timer, info->tempo, info->ppq);
+	if (result >= 0 && info->skew_base > 0)
+		result = snd_seq_timer_set_skew(q->timer, info->skew_value,
+						info->skew_base);
+	queue_access_unlock(q);
+	queuefree(q);
+	return result;
+}
+
+/* use or unuse this queue */
+static void queue_use(struct snd_seq_queue *queue, int client, int use)
+{
+	if (use) {
+		if (!test_and_set_bit(client, queue->clients_bitmap))
+			queue->clients++;
+	} else {
+		if (test_and_clear_bit(client, queue->clients_bitmap))
+			queue->clients--;
+	}
+	if (queue->clients) {
+		if (use && queue->clients == 1)
+			snd_seq_timer_defaults(queue->timer);
+		snd_seq_timer_open(queue);
+	} else {
+		snd_seq_timer_close(queue);
+	}
+}
+
+/* use or unuse this queue -
+ * if it is the first client, starts the timer.
+ * if it is not longer used by any clients, stop the timer.
+ */
+int snd_seq_queue_use(int queueid, int client, int use)
+{
+	struct snd_seq_queue *queue;
+
+	queue = queueptr(queueid);
+	if (queue == NULL)
+		return -EINVAL;
+	mutex_lock(&queue->timer_mutex);
+	queue_use(queue, client, use);
+	mutex_unlock(&queue->timer_mutex);
+	queuefree(queue);
+	return 0;
+}
+
+/*
+ * check if queue is used by the client
+ * return negative value if the queue is invalid.
+ * return 0 if not used, 1 if used.
+ */
+int snd_seq_queue_is_used(int queueid, int client)
+{
+	struct snd_seq_queue *q;
+	int result;
+
+	q = queueptr(queueid);
+	if (q == NULL)
+		return -EINVAL; /* invalid queue */
+	result = test_bit(client, q->clients_bitmap) ? 1 : 0;
+	queuefree(q);
+	return result;
+}
+
+
+/*----------------------------------------------------------------*/
+
+/* final stage notification -
+ * remove cells for no longer exist client (for non-owned queue)
+ * or delete this queue (for owned queue)
+ */
+void snd_seq_queue_client_leave(int client)
+{
+	int i;
+	struct snd_seq_queue *q;
+
+	/* delete own queues from queue list */
+	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
+		q = queue_list_remove(i, client);
+		if (q)
+			queue_delete(q);
+	}
+
+	/* remove cells from existing queues -
+	 * they are not owned by this client
+	 */
+	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
+		q = queueptr(i);
+		if (!q)
+			continue;
+		if (test_bit(client, q->clients_bitmap)) {
+			snd_seq_prioq_leave(q->tickq, client, 0);
+			snd_seq_prioq_leave(q->timeq, client, 0);
+			snd_seq_queue_use(q->queue, client, 0);
+		}
+		queuefree(q);
+	}
+}
+
+
+
+/*----------------------------------------------------------------*/
+
+/* remove cells from all queues */
+void snd_seq_queue_client_leave_cells(int client)
+{
+	int i;
+	struct snd_seq_queue *q;
+
+	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
+		q = queueptr(i);
+		if (!q)
+			continue;
+		snd_seq_prioq_leave(q->tickq, client, 0);
+		snd_seq_prioq_leave(q->timeq, client, 0);
+		queuefree(q);
+	}
+}
+
+/* remove cells based on flush criteria */
+void snd_seq_queue_remove_cells(int client, struct snd_seq_remove_events *info)
+{
+	int i;
+	struct snd_seq_queue *q;
+
+	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
+		q = queueptr(i);
+		if (!q)
+			continue;
+		if (test_bit(client, q->clients_bitmap) &&
+		    (! (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) ||
+		     q->queue == info->queue)) {
+			snd_seq_prioq_remove_events(q->tickq, client, info);
+			snd_seq_prioq_remove_events(q->timeq, client, info);
+		}
+		queuefree(q);
+	}
+}
+
+/*----------------------------------------------------------------*/
+
+/*
+ * send events to all subscribed ports
+ */
+static void queue_broadcast_event(struct snd_seq_queue *q, struct snd_seq_event *ev,
+				  int atomic, int hop)
+{
+	struct snd_seq_event sev;
+
+	sev = *ev;
+	
+	sev.flags = SNDRV_SEQ_TIME_STAMP_TICK|SNDRV_SEQ_TIME_MODE_ABS;
+	sev.time.tick = q->timer->tick.cur_tick;
+	sev.queue = q->queue;
+	sev.data.queue.queue = q->queue;
+
+	/* broadcast events from Timer port */
+	sev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
+	sev.source.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;
+	sev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
+	snd_seq_kernel_client_dispatch(SNDRV_SEQ_CLIENT_SYSTEM, &sev, atomic, hop);
+}
+
+/*
+ * process a received queue-control event.
+ * this function is exported for seq_sync.c.
+ */
+static void snd_seq_queue_process_event(struct snd_seq_queue *q,
+					struct snd_seq_event *ev,
+					int atomic, int hop)
+{
+	switch (ev->type) {
+	case SNDRV_SEQ_EVENT_START:
+		snd_seq_prioq_leave(q->tickq, ev->source.client, 1);
+		snd_seq_prioq_leave(q->timeq, ev->source.client, 1);
+		if (! snd_seq_timer_start(q->timer))
+			queue_broadcast_event(q, ev, atomic, hop);
+		break;
+
+	case SNDRV_SEQ_EVENT_CONTINUE:
+		if (! snd_seq_timer_continue(q->timer))
+			queue_broadcast_event(q, ev, atomic, hop);
+		break;
+
+	case SNDRV_SEQ_EVENT_STOP:
+		snd_seq_timer_stop(q->timer);
+		queue_broadcast_event(q, ev, atomic, hop);
+		break;
+
+	case SNDRV_SEQ_EVENT_TEMPO:
+		snd_seq_timer_set_tempo(q->timer, ev->data.queue.param.value);
+		queue_broadcast_event(q, ev, atomic, hop);
+		break;
+
+	case SNDRV_SEQ_EVENT_SETPOS_TICK:
+		if (snd_seq_timer_set_position_tick(q->timer, ev->data.queue.param.time.tick) == 0) {
+			queue_broadcast_event(q, ev, atomic, hop);
+		}
+		break;
+
+	case SNDRV_SEQ_EVENT_SETPOS_TIME:
+		if (snd_seq_timer_set_position_time(q->timer, ev->data.queue.param.time.time) == 0) {
+			queue_broadcast_event(q, ev, atomic, hop);
+		}
+		break;
+	case SNDRV_SEQ_EVENT_QUEUE_SKEW:
+		if (snd_seq_timer_set_skew(q->timer,
+					   ev->data.queue.param.skew.value,
+					   ev->data.queue.param.skew.base) == 0) {
+			queue_broadcast_event(q, ev, atomic, hop);
+		}
+		break;
+	}
+}
+
+
+/*
+ * Queue control via timer control port:
+ * this function is exported as a callback of timer port.
+ */
+int snd_seq_control_queue(struct snd_seq_event *ev, int atomic, int hop)
+{
+	struct snd_seq_queue *q;
+
+	if (snd_BUG_ON(!ev))
+		return -EINVAL;
+	q = queueptr(ev->data.queue.queue);
+
+	if (q == NULL)
+		return -EINVAL;
+
+	if (! queue_access_lock(q, ev->source.client)) {
+		queuefree(q);
+		return -EPERM;
+	}
+
+	snd_seq_queue_process_event(q, ev, atomic, hop);
+
+	queue_access_unlock(q);
+	queuefree(q);
+	return 0;
+}
+
+
+/*----------------------------------------------------------------*/
+
+#ifdef CONFIG_SND_PROC_FS
+/* exported to seq_info.c */
+void snd_seq_info_queues_read(struct snd_info_entry *entry, 
+			      struct snd_info_buffer *buffer)
+{
+	int i, bpm;
+	struct snd_seq_queue *q;
+	struct snd_seq_timer *tmr;
+	bool locked;
+	int owner;
+
+	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
+		q = queueptr(i);
+		if (!q)
+			continue;
+
+		tmr = q->timer;
+		if (tmr->tempo)
+			bpm = 60000000 / tmr->tempo;
+		else
+			bpm = 0;
+
+		spin_lock_irq(&q->owner_lock);
+		locked = q->locked;
+		owner = q->owner;
+		spin_unlock_irq(&q->owner_lock);
+
+		snd_iprintf(buffer, "queue %d: [%s]\n", q->queue, q->name);
+		snd_iprintf(buffer, "owned by client    : %d\n", owner);
+		snd_iprintf(buffer, "lock status        : %s\n", locked ? "Locked" : "Free");
+		snd_iprintf(buffer, "queued time events : %d\n", snd_seq_prioq_avail(q->timeq));
+		snd_iprintf(buffer, "queued tick events : %d\n", snd_seq_prioq_avail(q->tickq));
+		snd_iprintf(buffer, "timer state        : %s\n", tmr->running ? "Running" : "Stopped");
+		snd_iprintf(buffer, "timer PPQ          : %d\n", tmr->ppq);
+		snd_iprintf(buffer, "current tempo      : %d\n", tmr->tempo);
+		snd_iprintf(buffer, "current BPM        : %d\n", bpm);
+		snd_iprintf(buffer, "current time       : %d.%09d s\n", tmr->cur_time.tv_sec, tmr->cur_time.tv_nsec);
+		snd_iprintf(buffer, "current tick       : %d\n", tmr->tick.cur_tick);
+		snd_iprintf(buffer, "\n");
+		queuefree(q);
+	}
+}
+#endif /* CONFIG_SND_PROC_FS */
+