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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/iommu/io-pgfault.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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(). ...
Diffstat (limited to 'drivers/iommu/io-pgfault.c')
-rw-r--r--drivers/iommu/io-pgfault.c418
1 files changed, 418 insertions, 0 deletions
diff --git a/drivers/iommu/io-pgfault.c b/drivers/iommu/io-pgfault.c
new file mode 100644
index 000000000..e5b8b9110
--- /dev/null
+++ b/drivers/iommu/io-pgfault.c
@@ -0,0 +1,418 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Handle device page faults
+ *
+ * Copyright (C) 2020 ARM Ltd.
+ */
+
+#include <linux/iommu.h>
+#include <linux/list.h>
+#include <linux/sched/mm.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+
+#include "iommu-sva.h"
+
+/**
+ * struct iopf_queue - IO Page Fault queue
+ * @wq: the fault workqueue
+ * @devices: devices attached to this queue
+ * @lock: protects the device list
+ */
+struct iopf_queue {
+ struct workqueue_struct *wq;
+ struct list_head devices;
+ struct mutex lock;
+};
+
+/**
+ * struct iopf_device_param - IO Page Fault data attached to a device
+ * @dev: the device that owns this param
+ * @queue: IOPF queue
+ * @queue_list: index into queue->devices
+ * @partial: faults that are part of a Page Request Group for which the last
+ * request hasn't been submitted yet.
+ */
+struct iopf_device_param {
+ struct device *dev;
+ struct iopf_queue *queue;
+ struct list_head queue_list;
+ struct list_head partial;
+};
+
+struct iopf_fault {
+ struct iommu_fault fault;
+ struct list_head list;
+};
+
+struct iopf_group {
+ struct iopf_fault last_fault;
+ struct list_head faults;
+ struct work_struct work;
+ struct device *dev;
+};
+
+static int iopf_complete_group(struct device *dev, struct iopf_fault *iopf,
+ enum iommu_page_response_code status)
+{
+ struct iommu_page_response resp = {
+ .version = IOMMU_PAGE_RESP_VERSION_1,
+ .pasid = iopf->fault.prm.pasid,
+ .grpid = iopf->fault.prm.grpid,
+ .code = status,
+ };
+
+ if ((iopf->fault.prm.flags & IOMMU_FAULT_PAGE_REQUEST_PASID_VALID) &&
+ (iopf->fault.prm.flags & IOMMU_FAULT_PAGE_RESPONSE_NEEDS_PASID))
+ resp.flags = IOMMU_PAGE_RESP_PASID_VALID;
+
+ return iommu_page_response(dev, &resp);
+}
+
+static void iopf_handler(struct work_struct *work)
+{
+ struct iopf_group *group;
+ struct iommu_domain *domain;
+ struct iopf_fault *iopf, *next;
+ enum iommu_page_response_code status = IOMMU_PAGE_RESP_SUCCESS;
+
+ group = container_of(work, struct iopf_group, work);
+ domain = iommu_get_domain_for_dev_pasid(group->dev,
+ group->last_fault.fault.prm.pasid, 0);
+ if (!domain || !domain->iopf_handler)
+ status = IOMMU_PAGE_RESP_INVALID;
+
+ list_for_each_entry_safe(iopf, next, &group->faults, list) {
+ /*
+ * For the moment, errors are sticky: don't handle subsequent
+ * faults in the group if there is an error.
+ */
+ if (status == IOMMU_PAGE_RESP_SUCCESS)
+ status = domain->iopf_handler(&iopf->fault,
+ domain->fault_data);
+
+ if (!(iopf->fault.prm.flags &
+ IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE))
+ kfree(iopf);
+ }
+
+ iopf_complete_group(group->dev, &group->last_fault, status);
+ kfree(group);
+}
+
+/**
+ * iommu_queue_iopf - IO Page Fault handler
+ * @fault: fault event
+ * @cookie: struct device, passed to iommu_register_device_fault_handler.
+ *
+ * Add a fault to the device workqueue, to be handled by mm.
+ *
+ * This module doesn't handle PCI PASID Stop Marker; IOMMU drivers must discard
+ * them before reporting faults. A PASID Stop Marker (LRW = 0b100) doesn't
+ * expect a response. It may be generated when disabling a PASID (issuing a
+ * PASID stop request) by some PCI devices.
+ *
+ * The PASID stop request is issued by the device driver before unbind(). Once
+ * it completes, no page request is generated for this PASID anymore and
+ * outstanding ones have been pushed to the IOMMU (as per PCIe 4.0r1.0 - 6.20.1
+ * and 10.4.1.2 - Managing PASID TLP Prefix Usage). Some PCI devices will wait
+ * for all outstanding page requests to come back with a response before
+ * completing the PASID stop request. Others do not wait for page responses, and
+ * instead issue this Stop Marker that tells us when the PASID can be
+ * reallocated.
+ *
+ * It is safe to discard the Stop Marker because it is an optimization.
+ * a. Page requests, which are posted requests, have been flushed to the IOMMU
+ * when the stop request completes.
+ * b. The IOMMU driver flushes all fault queues on unbind() before freeing the
+ * PASID.
+ *
+ * So even though the Stop Marker might be issued by the device *after* the stop
+ * request completes, outstanding faults will have been dealt with by the time
+ * the PASID is freed.
+ *
+ * Any valid page fault will be eventually routed to an iommu domain and the
+ * page fault handler installed there will get called. The users of this
+ * handling framework should guarantee that the iommu domain could only be
+ * freed after the device has stopped generating page faults (or the iommu
+ * hardware has been set to block the page faults) and the pending page faults
+ * have been flushed.
+ *
+ * Return: 0 on success and <0 on error.
+ */
+int iommu_queue_iopf(struct iommu_fault *fault, void *cookie)
+{
+ int ret;
+ struct iopf_group *group;
+ struct iopf_fault *iopf, *next;
+ struct iopf_device_param *iopf_param;
+
+ struct device *dev = cookie;
+ struct dev_iommu *param = dev->iommu;
+
+ lockdep_assert_held(&param->lock);
+
+ if (fault->type != IOMMU_FAULT_PAGE_REQ)
+ /* Not a recoverable page fault */
+ return -EOPNOTSUPP;
+
+ /*
+ * As long as we're holding param->lock, the queue can't be unlinked
+ * from the device and therefore cannot disappear.
+ */
+ iopf_param = param->iopf_param;
+ if (!iopf_param)
+ return -ENODEV;
+
+ if (!(fault->prm.flags & IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE)) {
+ iopf = kzalloc(sizeof(*iopf), GFP_KERNEL);
+ if (!iopf)
+ return -ENOMEM;
+
+ iopf->fault = *fault;
+
+ /* Non-last request of a group. Postpone until the last one */
+ list_add(&iopf->list, &iopf_param->partial);
+
+ return 0;
+ }
+
+ group = kzalloc(sizeof(*group), GFP_KERNEL);
+ if (!group) {
+ /*
+ * The caller will send a response to the hardware. But we do
+ * need to clean up before leaving, otherwise partial faults
+ * will be stuck.
+ */
+ ret = -ENOMEM;
+ goto cleanup_partial;
+ }
+
+ group->dev = dev;
+ group->last_fault.fault = *fault;
+ INIT_LIST_HEAD(&group->faults);
+ list_add(&group->last_fault.list, &group->faults);
+ INIT_WORK(&group->work, iopf_handler);
+
+ /* See if we have partial faults for this group */
+ list_for_each_entry_safe(iopf, next, &iopf_param->partial, list) {
+ if (iopf->fault.prm.grpid == fault->prm.grpid)
+ /* Insert *before* the last fault */
+ list_move(&iopf->list, &group->faults);
+ }
+
+ queue_work(iopf_param->queue->wq, &group->work);
+ return 0;
+
+cleanup_partial:
+ list_for_each_entry_safe(iopf, next, &iopf_param->partial, list) {
+ if (iopf->fault.prm.grpid == fault->prm.grpid) {
+ list_del(&iopf->list);
+ kfree(iopf);
+ }
+ }
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_queue_iopf);
+
+/**
+ * iopf_queue_flush_dev - Ensure that all queued faults have been processed
+ * @dev: the endpoint whose faults need to be flushed.
+ *
+ * The IOMMU driver calls this before releasing a PASID, to ensure that all
+ * pending faults for this PASID have been handled, and won't hit the address
+ * space of the next process that uses this PASID. The driver must make sure
+ * that no new fault is added to the queue. In particular it must flush its
+ * low-level queue before calling this function.
+ *
+ * Return: 0 on success and <0 on error.
+ */
+int iopf_queue_flush_dev(struct device *dev)
+{
+ int ret = 0;
+ struct iopf_device_param *iopf_param;
+ struct dev_iommu *param = dev->iommu;
+
+ if (!param)
+ return -ENODEV;
+
+ mutex_lock(&param->lock);
+ iopf_param = param->iopf_param;
+ if (iopf_param)
+ flush_workqueue(iopf_param->queue->wq);
+ else
+ ret = -ENODEV;
+ mutex_unlock(&param->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iopf_queue_flush_dev);
+
+/**
+ * iopf_queue_discard_partial - Remove all pending partial fault
+ * @queue: the queue whose partial faults need to be discarded
+ *
+ * When the hardware queue overflows, last page faults in a group may have been
+ * lost and the IOMMU driver calls this to discard all partial faults. The
+ * driver shouldn't be adding new faults to this queue concurrently.
+ *
+ * Return: 0 on success and <0 on error.
+ */
+int iopf_queue_discard_partial(struct iopf_queue *queue)
+{
+ struct iopf_fault *iopf, *next;
+ struct iopf_device_param *iopf_param;
+
+ if (!queue)
+ return -EINVAL;
+
+ mutex_lock(&queue->lock);
+ list_for_each_entry(iopf_param, &queue->devices, queue_list) {
+ list_for_each_entry_safe(iopf, next, &iopf_param->partial,
+ list) {
+ list_del(&iopf->list);
+ kfree(iopf);
+ }
+ }
+ mutex_unlock(&queue->lock);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iopf_queue_discard_partial);
+
+/**
+ * iopf_queue_add_device - Add producer to the fault queue
+ * @queue: IOPF queue
+ * @dev: device to add
+ *
+ * Return: 0 on success and <0 on error.
+ */
+int iopf_queue_add_device(struct iopf_queue *queue, struct device *dev)
+{
+ int ret = -EBUSY;
+ struct iopf_device_param *iopf_param;
+ struct dev_iommu *param = dev->iommu;
+
+ if (!param)
+ return -ENODEV;
+
+ iopf_param = kzalloc(sizeof(*iopf_param), GFP_KERNEL);
+ if (!iopf_param)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&iopf_param->partial);
+ iopf_param->queue = queue;
+ iopf_param->dev = dev;
+
+ mutex_lock(&queue->lock);
+ mutex_lock(&param->lock);
+ if (!param->iopf_param) {
+ list_add(&iopf_param->queue_list, &queue->devices);
+ param->iopf_param = iopf_param;
+ ret = 0;
+ }
+ mutex_unlock(&param->lock);
+ mutex_unlock(&queue->lock);
+
+ if (ret)
+ kfree(iopf_param);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iopf_queue_add_device);
+
+/**
+ * iopf_queue_remove_device - Remove producer from fault queue
+ * @queue: IOPF queue
+ * @dev: device to remove
+ *
+ * Caller makes sure that no more faults are reported for this device.
+ *
+ * Return: 0 on success and <0 on error.
+ */
+int iopf_queue_remove_device(struct iopf_queue *queue, struct device *dev)
+{
+ int ret = -EINVAL;
+ struct iopf_fault *iopf, *next;
+ struct iopf_device_param *iopf_param;
+ struct dev_iommu *param = dev->iommu;
+
+ if (!param || !queue)
+ return -EINVAL;
+
+ mutex_lock(&queue->lock);
+ mutex_lock(&param->lock);
+ iopf_param = param->iopf_param;
+ if (iopf_param && iopf_param->queue == queue) {
+ list_del(&iopf_param->queue_list);
+ param->iopf_param = NULL;
+ ret = 0;
+ }
+ mutex_unlock(&param->lock);
+ mutex_unlock(&queue->lock);
+ if (ret)
+ return ret;
+
+ /* Just in case some faults are still stuck */
+ list_for_each_entry_safe(iopf, next, &iopf_param->partial, list)
+ kfree(iopf);
+
+ kfree(iopf_param);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iopf_queue_remove_device);
+
+/**
+ * iopf_queue_alloc - Allocate and initialize a fault queue
+ * @name: a unique string identifying the queue (for workqueue)
+ *
+ * Return: the queue on success and NULL on error.
+ */
+struct iopf_queue *iopf_queue_alloc(const char *name)
+{
+ struct iopf_queue *queue;
+
+ queue = kzalloc(sizeof(*queue), GFP_KERNEL);
+ if (!queue)
+ return NULL;
+
+ /*
+ * The WQ is unordered because the low-level handler enqueues faults by
+ * group. PRI requests within a group have to be ordered, but once
+ * that's dealt with, the high-level function can handle groups out of
+ * order.
+ */
+ queue->wq = alloc_workqueue("iopf_queue/%s", WQ_UNBOUND, 0, name);
+ if (!queue->wq) {
+ kfree(queue);
+ return NULL;
+ }
+
+ INIT_LIST_HEAD(&queue->devices);
+ mutex_init(&queue->lock);
+
+ return queue;
+}
+EXPORT_SYMBOL_GPL(iopf_queue_alloc);
+
+/**
+ * iopf_queue_free - Free IOPF queue
+ * @queue: queue to free
+ *
+ * Counterpart to iopf_queue_alloc(). The driver must not be queuing faults or
+ * adding/removing devices on this queue anymore.
+ */
+void iopf_queue_free(struct iopf_queue *queue)
+{
+ struct iopf_device_param *iopf_param, *next;
+
+ if (!queue)
+ return;
+
+ list_for_each_entry_safe(iopf_param, next, &queue->devices, queue_list)
+ iopf_queue_remove_device(queue, iopf_param->dev);
+
+ destroy_workqueue(queue->wq);
+ kfree(queue);
+}
+EXPORT_SYMBOL_GPL(iopf_queue_free);