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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/pci/msi/api.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
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/pci/msi/api.c')
-rw-r--r--drivers/pci/msi/api.c458
1 files changed, 458 insertions, 0 deletions
diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
new file mode 100644
index 000000000..b8009aa11
--- /dev/null
+++ b/drivers/pci/msi/api.c
@@ -0,0 +1,458 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCI MSI/MSI-X — Exported APIs for device drivers
+ *
+ * Copyright (C) 2003-2004 Intel
+ * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
+ * Copyright (C) 2016 Christoph Hellwig.
+ * Copyright (C) 2022 Linutronix GmbH
+ */
+
+#include <linux/export.h>
+#include <linux/irq.h>
+
+#include "msi.h"
+
+/**
+ * pci_enable_msi() - Enable MSI interrupt mode on device
+ * @dev: the PCI device to operate on
+ *
+ * Legacy device driver API to enable MSI interrupts mode on device and
+ * allocate a single interrupt vector. On success, the allocated vector
+ * Linux IRQ will be saved at @dev->irq. The driver must invoke
+ * pci_disable_msi() on cleanup.
+ *
+ * NOTE: The newer pci_alloc_irq_vectors() / pci_free_irq_vectors() API
+ * pair should, in general, be used instead.
+ *
+ * Return: 0 on success, errno otherwise
+ */
+int pci_enable_msi(struct pci_dev *dev)
+{
+ int rc = __pci_enable_msi_range(dev, 1, 1, NULL);
+ if (rc < 0)
+ return rc;
+ return 0;
+}
+EXPORT_SYMBOL(pci_enable_msi);
+
+/**
+ * pci_disable_msi() - Disable MSI interrupt mode on device
+ * @dev: the PCI device to operate on
+ *
+ * Legacy device driver API to disable MSI interrupt mode on device,
+ * free earlier allocated interrupt vectors, and restore INTx emulation.
+ * The PCI device Linux IRQ (@dev->irq) is restored to its default
+ * pin-assertion IRQ. This is the cleanup pair of pci_enable_msi().
+ *
+ * NOTE: The newer pci_alloc_irq_vectors() / pci_free_irq_vectors() API
+ * pair should, in general, be used instead.
+ */
+void pci_disable_msi(struct pci_dev *dev)
+{
+ if (!pci_msi_enabled() || !dev || !dev->msi_enabled)
+ return;
+
+ msi_lock_descs(&dev->dev);
+ pci_msi_shutdown(dev);
+ pci_free_msi_irqs(dev);
+ msi_unlock_descs(&dev->dev);
+}
+EXPORT_SYMBOL(pci_disable_msi);
+
+/**
+ * pci_msix_vec_count() - Get number of MSI-X interrupt vectors on device
+ * @dev: the PCI device to operate on
+ *
+ * Return: number of MSI-X interrupt vectors available on this device
+ * (i.e., the device's MSI-X capability structure "table size"), -EINVAL
+ * if the device is not MSI-X capable, other errnos otherwise.
+ */
+int pci_msix_vec_count(struct pci_dev *dev)
+{
+ u16 control;
+
+ if (!dev->msix_cap)
+ return -EINVAL;
+
+ pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
+ return msix_table_size(control);
+}
+EXPORT_SYMBOL(pci_msix_vec_count);
+
+/**
+ * pci_enable_msix_range() - Enable MSI-X interrupt mode on device
+ * @dev: the PCI device to operate on
+ * @entries: input/output parameter, array of MSI-X configuration entries
+ * @minvec: minimum required number of MSI-X vectors
+ * @maxvec: maximum desired number of MSI-X vectors
+ *
+ * Legacy device driver API to enable MSI-X interrupt mode on device and
+ * configure its MSI-X capability structure as appropriate. The passed
+ * @entries array must have each of its members "entry" field set to a
+ * desired (valid) MSI-X vector number, where the range of valid MSI-X
+ * vector numbers can be queried through pci_msix_vec_count(). If
+ * successful, the driver must invoke pci_disable_msix() on cleanup.
+ *
+ * NOTE: The newer pci_alloc_irq_vectors() / pci_free_irq_vectors() API
+ * pair should, in general, be used instead.
+ *
+ * Return: number of MSI-X vectors allocated (which might be smaller
+ * than @maxvecs), where Linux IRQ numbers for such allocated vectors
+ * are saved back in the @entries array elements' "vector" field. Return
+ * -ENOSPC if less than @minvecs interrupt vectors are available.
+ * Return -EINVAL if one of the passed @entries members "entry" field
+ * was invalid or a duplicate, or if plain MSI interrupts mode was
+ * earlier enabled on device. Return other errnos otherwise.
+ */
+int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
+ int minvec, int maxvec)
+{
+ return __pci_enable_msix_range(dev, entries, minvec, maxvec, NULL, 0);
+}
+EXPORT_SYMBOL(pci_enable_msix_range);
+
+/**
+ * pci_msix_can_alloc_dyn - Query whether dynamic allocation after enabling
+ * MSI-X is supported
+ *
+ * @dev: PCI device to operate on
+ *
+ * Return: True if supported, false otherwise
+ */
+bool pci_msix_can_alloc_dyn(struct pci_dev *dev)
+{
+ if (!dev->msix_cap)
+ return false;
+
+ return pci_msi_domain_supports(dev, MSI_FLAG_PCI_MSIX_ALLOC_DYN, DENY_LEGACY);
+}
+EXPORT_SYMBOL_GPL(pci_msix_can_alloc_dyn);
+
+/**
+ * pci_msix_alloc_irq_at - Allocate an MSI-X interrupt after enabling MSI-X
+ * at a given MSI-X vector index or any free vector index
+ *
+ * @dev: PCI device to operate on
+ * @index: Index to allocate. If @index == MSI_ANY_INDEX this allocates
+ * the next free index in the MSI-X table
+ * @affdesc: Optional pointer to an affinity descriptor structure. NULL otherwise
+ *
+ * Return: A struct msi_map
+ *
+ * On success msi_map::index contains the allocated index (>= 0) and
+ * msi_map::virq contains the allocated Linux interrupt number (> 0).
+ *
+ * On fail msi_map::index contains the error code and msi_map::virq
+ * is set to 0.
+ */
+struct msi_map pci_msix_alloc_irq_at(struct pci_dev *dev, unsigned int index,
+ const struct irq_affinity_desc *affdesc)
+{
+ struct msi_map map = { .index = -ENOTSUPP };
+
+ if (!dev->msix_enabled)
+ return map;
+
+ if (!pci_msix_can_alloc_dyn(dev))
+ return map;
+
+ return msi_domain_alloc_irq_at(&dev->dev, MSI_DEFAULT_DOMAIN, index, affdesc, NULL);
+}
+EXPORT_SYMBOL_GPL(pci_msix_alloc_irq_at);
+
+/**
+ * pci_msix_free_irq - Free an interrupt on a PCI/MSIX interrupt domain
+ * which was allocated via pci_msix_alloc_irq_at()
+ *
+ * @dev: The PCI device to operate on
+ * @map: A struct msi_map describing the interrupt to free
+ * as returned from the allocation function.
+ */
+void pci_msix_free_irq(struct pci_dev *dev, struct msi_map map)
+{
+ if (WARN_ON_ONCE(map.index < 0 || map.virq <= 0))
+ return;
+ if (WARN_ON_ONCE(!pci_msix_can_alloc_dyn(dev)))
+ return;
+ msi_domain_free_irqs_range(&dev->dev, MSI_DEFAULT_DOMAIN, map.index, map.index);
+}
+EXPORT_SYMBOL_GPL(pci_msix_free_irq);
+
+/**
+ * pci_disable_msix() - Disable MSI-X interrupt mode on device
+ * @dev: the PCI device to operate on
+ *
+ * Legacy device driver API to disable MSI-X interrupt mode on device,
+ * free earlier-allocated interrupt vectors, and restore INTx.
+ * The PCI device Linux IRQ (@dev->irq) is restored to its default pin
+ * assertion IRQ. This is the cleanup pair of pci_enable_msix_range().
+ *
+ * NOTE: The newer pci_alloc_irq_vectors() / pci_free_irq_vectors() API
+ * pair should, in general, be used instead.
+ */
+void pci_disable_msix(struct pci_dev *dev)
+{
+ if (!pci_msi_enabled() || !dev || !dev->msix_enabled)
+ return;
+
+ msi_lock_descs(&dev->dev);
+ pci_msix_shutdown(dev);
+ pci_free_msi_irqs(dev);
+ msi_unlock_descs(&dev->dev);
+}
+EXPORT_SYMBOL(pci_disable_msix);
+
+/**
+ * pci_alloc_irq_vectors() - Allocate multiple device interrupt vectors
+ * @dev: the PCI device to operate on
+ * @min_vecs: minimum required number of vectors (must be >= 1)
+ * @max_vecs: maximum desired number of vectors
+ * @flags: One or more of:
+ *
+ * * %PCI_IRQ_MSIX Allow trying MSI-X vector allocations
+ * * %PCI_IRQ_MSI Allow trying MSI vector allocations
+ *
+ * * %PCI_IRQ_LEGACY Allow trying legacy INTx interrupts, if
+ * and only if @min_vecs == 1
+ *
+ * * %PCI_IRQ_AFFINITY Auto-manage IRQs affinity by spreading
+ * the vectors around available CPUs
+ *
+ * Allocate up to @max_vecs interrupt vectors on device. MSI-X irq
+ * vector allocation has a higher precedence over plain MSI, which has a
+ * higher precedence over legacy INTx emulation.
+ *
+ * Upon a successful allocation, the caller should use pci_irq_vector()
+ * to get the Linux IRQ number to be passed to request_threaded_irq().
+ * The driver must call pci_free_irq_vectors() on cleanup.
+ *
+ * Return: number of allocated vectors (which might be smaller than
+ * @max_vecs), -ENOSPC if less than @min_vecs interrupt vectors are
+ * available, other errnos otherwise.
+ */
+int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
+ unsigned int max_vecs, unsigned int flags)
+{
+ return pci_alloc_irq_vectors_affinity(dev, min_vecs, max_vecs,
+ flags, NULL);
+}
+EXPORT_SYMBOL(pci_alloc_irq_vectors);
+
+/**
+ * pci_alloc_irq_vectors_affinity() - Allocate multiple device interrupt
+ * vectors with affinity requirements
+ * @dev: the PCI device to operate on
+ * @min_vecs: minimum required number of vectors (must be >= 1)
+ * @max_vecs: maximum desired number of vectors
+ * @flags: allocation flags, as in pci_alloc_irq_vectors()
+ * @affd: affinity requirements (can be %NULL).
+ *
+ * Same as pci_alloc_irq_vectors(), but with the extra @affd parameter.
+ * Check that function docs, and &struct irq_affinity, for more details.
+ */
+int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
+ unsigned int max_vecs, unsigned int flags,
+ struct irq_affinity *affd)
+{
+ struct irq_affinity msi_default_affd = {0};
+ int nvecs = -ENOSPC;
+
+ if (flags & PCI_IRQ_AFFINITY) {
+ if (!affd)
+ affd = &msi_default_affd;
+ } else {
+ if (WARN_ON(affd))
+ affd = NULL;
+ }
+
+ if (flags & PCI_IRQ_MSIX) {
+ nvecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs,
+ affd, flags);
+ if (nvecs > 0)
+ return nvecs;
+ }
+
+ if (flags & PCI_IRQ_MSI) {
+ nvecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd);
+ if (nvecs > 0)
+ return nvecs;
+ }
+
+ /* use legacy IRQ if allowed */
+ if (flags & PCI_IRQ_LEGACY) {
+ if (min_vecs == 1 && dev->irq) {
+ /*
+ * Invoke the affinity spreading logic to ensure that
+ * the device driver can adjust queue configuration
+ * for the single interrupt case.
+ */
+ if (affd)
+ irq_create_affinity_masks(1, affd);
+ pci_intx(dev, 1);
+ return 1;
+ }
+ }
+
+ return nvecs;
+}
+EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity);
+
+/**
+ * pci_irq_vector() - Get Linux IRQ number of a device interrupt vector
+ * @dev: the PCI device to operate on
+ * @nr: device-relative interrupt vector index (0-based); has different
+ * meanings, depending on interrupt mode:
+ *
+ * * MSI-X the index in the MSI-X vector table
+ * * MSI the index of the enabled MSI vectors
+ * * INTx must be 0
+ *
+ * Return: the Linux IRQ number, or -EINVAL if @nr is out of range
+ */
+int pci_irq_vector(struct pci_dev *dev, unsigned int nr)
+{
+ unsigned int irq;
+
+ if (!dev->msi_enabled && !dev->msix_enabled)
+ return !nr ? dev->irq : -EINVAL;
+
+ irq = msi_get_virq(&dev->dev, nr);
+ return irq ? irq : -EINVAL;
+}
+EXPORT_SYMBOL(pci_irq_vector);
+
+/**
+ * pci_irq_get_affinity() - Get a device interrupt vector affinity
+ * @dev: the PCI device to operate on
+ * @nr: device-relative interrupt vector index (0-based); has different
+ * meanings, depending on interrupt mode:
+ *
+ * * MSI-X the index in the MSI-X vector table
+ * * MSI the index of the enabled MSI vectors
+ * * INTx must be 0
+ *
+ * Return: MSI/MSI-X vector affinity, NULL if @nr is out of range or if
+ * the MSI(-X) vector was allocated without explicit affinity
+ * requirements (e.g., by pci_enable_msi(), pci_enable_msix_range(), or
+ * pci_alloc_irq_vectors() without the %PCI_IRQ_AFFINITY flag). Return a
+ * generic set of CPU IDs representing all possible CPUs available
+ * during system boot if the device is in legacy INTx mode.
+ */
+const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr)
+{
+ int idx, irq = pci_irq_vector(dev, nr);
+ struct msi_desc *desc;
+
+ if (WARN_ON_ONCE(irq <= 0))
+ return NULL;
+
+ desc = irq_get_msi_desc(irq);
+ /* Non-MSI does not have the information handy */
+ if (!desc)
+ return cpu_possible_mask;
+
+ /* MSI[X] interrupts can be allocated without affinity descriptor */
+ if (!desc->affinity)
+ return NULL;
+
+ /*
+ * MSI has a mask array in the descriptor.
+ * MSI-X has a single mask.
+ */
+ idx = dev->msi_enabled ? nr : 0;
+ return &desc->affinity[idx].mask;
+}
+EXPORT_SYMBOL(pci_irq_get_affinity);
+
+/**
+ * pci_ims_alloc_irq - Allocate an interrupt on a PCI/IMS interrupt domain
+ * @dev: The PCI device to operate on
+ * @icookie: Pointer to an IMS implementation specific cookie for this
+ * IMS instance (PASID, queue ID, pointer...).
+ * The cookie content is copied into the MSI descriptor for the
+ * interrupt chip callbacks or domain specific setup functions.
+ * @affdesc: Optional pointer to an interrupt affinity descriptor
+ *
+ * There is no index for IMS allocations as IMS is an implementation
+ * specific storage and does not have any direct associations between
+ * index, which might be a pure software construct, and device
+ * functionality. This association is established by the driver either via
+ * the index - if there is a hardware table - or in case of purely software
+ * managed IMS implementation the association happens via the
+ * irq_write_msi_msg() callback of the implementation specific interrupt
+ * chip, which utilizes the provided @icookie to store the MSI message in
+ * the appropriate place.
+ *
+ * Return: A struct msi_map
+ *
+ * On success msi_map::index contains the allocated index (>= 0) and
+ * msi_map::virq the allocated Linux interrupt number (> 0).
+ *
+ * On fail msi_map::index contains the error code and msi_map::virq
+ * is set to 0.
+ */
+struct msi_map pci_ims_alloc_irq(struct pci_dev *dev, union msi_instance_cookie *icookie,
+ const struct irq_affinity_desc *affdesc)
+{
+ return msi_domain_alloc_irq_at(&dev->dev, MSI_SECONDARY_DOMAIN, MSI_ANY_INDEX,
+ affdesc, icookie);
+}
+EXPORT_SYMBOL_GPL(pci_ims_alloc_irq);
+
+/**
+ * pci_ims_free_irq - Allocate an interrupt on a PCI/IMS interrupt domain
+ * which was allocated via pci_ims_alloc_irq()
+ * @dev: The PCI device to operate on
+ * @map: A struct msi_map describing the interrupt to free as
+ * returned from pci_ims_alloc_irq()
+ */
+void pci_ims_free_irq(struct pci_dev *dev, struct msi_map map)
+{
+ if (WARN_ON_ONCE(map.index < 0 || map.virq <= 0))
+ return;
+ msi_domain_free_irqs_range(&dev->dev, MSI_SECONDARY_DOMAIN, map.index, map.index);
+}
+EXPORT_SYMBOL_GPL(pci_ims_free_irq);
+
+/**
+ * pci_free_irq_vectors() - Free previously allocated IRQs for a device
+ * @dev: the PCI device to operate on
+ *
+ * Undo the interrupt vector allocations and possible device MSI/MSI-X
+ * enablement earlier done through pci_alloc_irq_vectors_affinity() or
+ * pci_alloc_irq_vectors().
+ */
+void pci_free_irq_vectors(struct pci_dev *dev)
+{
+ pci_disable_msix(dev);
+ pci_disable_msi(dev);
+}
+EXPORT_SYMBOL(pci_free_irq_vectors);
+
+/**
+ * pci_restore_msi_state() - Restore cached MSI(-X) state on device
+ * @dev: the PCI device to operate on
+ *
+ * Write the Linux-cached MSI(-X) state back on device. This is
+ * typically useful upon system resume, or after an error-recovery PCI
+ * adapter reset.
+ */
+void pci_restore_msi_state(struct pci_dev *dev)
+{
+ __pci_restore_msi_state(dev);
+ __pci_restore_msix_state(dev);
+}
+EXPORT_SYMBOL_GPL(pci_restore_msi_state);
+
+/**
+ * pci_msi_enabled() - Are MSI(-X) interrupts enabled system-wide?
+ *
+ * Return: true if MSI has not been globally disabled through ACPI FADT,
+ * PCI bridge quirks, or the "pci=nomsi" kernel command-line option.
+ */
+int pci_msi_enabled(void)
+{
+ return pci_msi_enable;
+}
+EXPORT_SYMBOL(pci_msi_enabled);