aboutsummaryrefslogtreecommitdiff
path: root/drivers/misc/cxl/context.c
diff options
context:
space:
mode:
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/misc/cxl/context.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/misc/cxl/context.c')
-rw-r--r--drivers/misc/cxl/context.c362
1 files changed, 362 insertions, 0 deletions
diff --git a/drivers/misc/cxl/context.c b/drivers/misc/cxl/context.c
new file mode 100644
index 000000000..acaa44809
--- /dev/null
+++ b/drivers/misc/cxl/context.c
@@ -0,0 +1,362 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2014 IBM Corp.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/bitmap.h>
+#include <linux/sched.h>
+#include <linux/pid.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/debugfs.h>
+#include <linux/slab.h>
+#include <linux/idr.h>
+#include <linux/sched/mm.h>
+#include <linux/mmu_context.h>
+#include <asm/cputable.h>
+#include <asm/current.h>
+#include <asm/copro.h>
+
+#include "cxl.h"
+
+/*
+ * Allocates space for a CXL context.
+ */
+struct cxl_context *cxl_context_alloc(void)
+{
+ return kzalloc(sizeof(struct cxl_context), GFP_KERNEL);
+}
+
+/*
+ * Initialises a CXL context.
+ */
+int cxl_context_init(struct cxl_context *ctx, struct cxl_afu *afu, bool master)
+{
+ int i;
+
+ ctx->afu = afu;
+ ctx->master = master;
+ ctx->pid = NULL; /* Set in start work ioctl */
+ mutex_init(&ctx->mapping_lock);
+ ctx->mapping = NULL;
+ ctx->tidr = 0;
+ ctx->assign_tidr = false;
+
+ if (cxl_is_power8()) {
+ spin_lock_init(&ctx->sste_lock);
+
+ /*
+ * Allocate the segment table before we put it in the IDR so that we
+ * can always access it when dereferenced from IDR. For the same
+ * reason, the segment table is only destroyed after the context is
+ * removed from the IDR. Access to this in the IOCTL is protected by
+ * Linux filesystem semantics (can't IOCTL until open is complete).
+ */
+ i = cxl_alloc_sst(ctx);
+ if (i)
+ return i;
+ }
+
+ INIT_WORK(&ctx->fault_work, cxl_handle_fault);
+
+ init_waitqueue_head(&ctx->wq);
+ spin_lock_init(&ctx->lock);
+
+ ctx->irq_bitmap = NULL;
+ ctx->pending_irq = false;
+ ctx->pending_fault = false;
+ ctx->pending_afu_err = false;
+
+ INIT_LIST_HEAD(&ctx->irq_names);
+
+ /*
+ * When we have to destroy all contexts in cxl_context_detach_all() we
+ * end up with afu_release_irqs() called from inside a
+ * idr_for_each_entry(). Hence we need to make sure that anything
+ * dereferenced from this IDR is ok before we allocate the IDR here.
+ * This clears out the IRQ ranges to ensure this.
+ */
+ for (i = 0; i < CXL_IRQ_RANGES; i++)
+ ctx->irqs.range[i] = 0;
+
+ mutex_init(&ctx->status_mutex);
+
+ ctx->status = OPENED;
+
+ /*
+ * Allocating IDR! We better make sure everything's setup that
+ * dereferences from it.
+ */
+ mutex_lock(&afu->contexts_lock);
+ idr_preload(GFP_KERNEL);
+ i = idr_alloc(&ctx->afu->contexts_idr, ctx, 0,
+ ctx->afu->num_procs, GFP_NOWAIT);
+ idr_preload_end();
+ mutex_unlock(&afu->contexts_lock);
+ if (i < 0)
+ return i;
+
+ ctx->pe = i;
+ if (cpu_has_feature(CPU_FTR_HVMODE)) {
+ ctx->elem = &ctx->afu->native->spa[i];
+ ctx->external_pe = ctx->pe;
+ } else {
+ ctx->external_pe = -1; /* assigned when attaching */
+ }
+ ctx->pe_inserted = false;
+
+ /*
+ * take a ref on the afu so that it stays alive at-least till
+ * this context is reclaimed inside reclaim_ctx.
+ */
+ cxl_afu_get(afu);
+ return 0;
+}
+
+void cxl_context_set_mapping(struct cxl_context *ctx,
+ struct address_space *mapping)
+{
+ mutex_lock(&ctx->mapping_lock);
+ ctx->mapping = mapping;
+ mutex_unlock(&ctx->mapping_lock);
+}
+
+static vm_fault_t cxl_mmap_fault(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct cxl_context *ctx = vma->vm_file->private_data;
+ u64 area, offset;
+ vm_fault_t ret;
+
+ offset = vmf->pgoff << PAGE_SHIFT;
+
+ pr_devel("%s: pe: %i address: 0x%lx offset: 0x%llx\n",
+ __func__, ctx->pe, vmf->address, offset);
+
+ if (ctx->afu->current_mode == CXL_MODE_DEDICATED) {
+ area = ctx->afu->psn_phys;
+ if (offset >= ctx->afu->adapter->ps_size)
+ return VM_FAULT_SIGBUS;
+ } else {
+ area = ctx->psn_phys;
+ if (offset >= ctx->psn_size)
+ return VM_FAULT_SIGBUS;
+ }
+
+ mutex_lock(&ctx->status_mutex);
+
+ if (ctx->status != STARTED) {
+ mutex_unlock(&ctx->status_mutex);
+ pr_devel("%s: Context not started, failing problem state access\n", __func__);
+ if (ctx->mmio_err_ff) {
+ if (!ctx->ff_page) {
+ ctx->ff_page = alloc_page(GFP_USER);
+ if (!ctx->ff_page)
+ return VM_FAULT_OOM;
+ memset(page_address(ctx->ff_page), 0xff, PAGE_SIZE);
+ }
+ get_page(ctx->ff_page);
+ vmf->page = ctx->ff_page;
+ vma->vm_page_prot = pgprot_cached(vma->vm_page_prot);
+ return 0;
+ }
+ return VM_FAULT_SIGBUS;
+ }
+
+ ret = vmf_insert_pfn(vma, vmf->address, (area + offset) >> PAGE_SHIFT);
+
+ mutex_unlock(&ctx->status_mutex);
+
+ return ret;
+}
+
+static const struct vm_operations_struct cxl_mmap_vmops = {
+ .fault = cxl_mmap_fault,
+};
+
+/*
+ * Map a per-context mmio space into the given vma.
+ */
+int cxl_context_iomap(struct cxl_context *ctx, struct vm_area_struct *vma)
+{
+ u64 start = vma->vm_pgoff << PAGE_SHIFT;
+ u64 len = vma->vm_end - vma->vm_start;
+
+ if (ctx->afu->current_mode == CXL_MODE_DEDICATED) {
+ if (start + len > ctx->afu->adapter->ps_size)
+ return -EINVAL;
+
+ if (cxl_is_power9()) {
+ /*
+ * Make sure there is a valid problem state
+ * area space for this AFU.
+ */
+ if (ctx->master && !ctx->afu->psa) {
+ pr_devel("AFU doesn't support mmio space\n");
+ return -EINVAL;
+ }
+
+ /* Can't mmap until the AFU is enabled */
+ if (!ctx->afu->enabled)
+ return -EBUSY;
+ }
+ } else {
+ if (start + len > ctx->psn_size)
+ return -EINVAL;
+
+ /* Make sure there is a valid per process space for this AFU */
+ if ((ctx->master && !ctx->afu->psa) || (!ctx->afu->pp_psa)) {
+ pr_devel("AFU doesn't support mmio space\n");
+ return -EINVAL;
+ }
+
+ /* Can't mmap until the AFU is enabled */
+ if (!ctx->afu->enabled)
+ return -EBUSY;
+ }
+
+ pr_devel("%s: mmio physical: %llx pe: %i master:%i\n", __func__,
+ ctx->psn_phys, ctx->pe , ctx->master);
+
+ vma->vm_flags |= VM_IO | VM_PFNMAP;
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+ vma->vm_ops = &cxl_mmap_vmops;
+ return 0;
+}
+
+/*
+ * Detach a context from the hardware. This disables interrupts and doesn't
+ * return until all outstanding interrupts for this context have completed. The
+ * hardware should no longer access *ctx after this has returned.
+ */
+int __detach_context(struct cxl_context *ctx)
+{
+ enum cxl_context_status status;
+
+ mutex_lock(&ctx->status_mutex);
+ status = ctx->status;
+ ctx->status = CLOSED;
+ mutex_unlock(&ctx->status_mutex);
+ if (status != STARTED)
+ return -EBUSY;
+
+ /* Only warn if we detached while the link was OK.
+ * If detach fails when hw is down, we don't care.
+ */
+ WARN_ON(cxl_ops->detach_process(ctx) &&
+ cxl_ops->link_ok(ctx->afu->adapter, ctx->afu));
+ flush_work(&ctx->fault_work); /* Only needed for dedicated process */
+
+ /*
+ * Wait until no further interrupts are presented by the PSL
+ * for this context.
+ */
+ if (cxl_ops->irq_wait)
+ cxl_ops->irq_wait(ctx);
+
+ /* release the reference to the group leader and mm handling pid */
+ put_pid(ctx->pid);
+
+ cxl_ctx_put();
+
+ /* Decrease the attached context count on the adapter */
+ cxl_adapter_context_put(ctx->afu->adapter);
+
+ /* Decrease the mm count on the context */
+ cxl_context_mm_count_put(ctx);
+ if (ctx->mm)
+ mm_context_remove_copro(ctx->mm);
+ ctx->mm = NULL;
+
+ return 0;
+}
+
+/*
+ * Detach the given context from the AFU. This doesn't actually
+ * free the context but it should stop the context running in hardware
+ * (ie. prevent this context from generating any further interrupts
+ * so that it can be freed).
+ */
+void cxl_context_detach(struct cxl_context *ctx)
+{
+ int rc;
+
+ rc = __detach_context(ctx);
+ if (rc)
+ return;
+
+ afu_release_irqs(ctx, ctx);
+ wake_up_all(&ctx->wq);
+}
+
+/*
+ * Detach all contexts on the given AFU.
+ */
+void cxl_context_detach_all(struct cxl_afu *afu)
+{
+ struct cxl_context *ctx;
+ int tmp;
+
+ mutex_lock(&afu->contexts_lock);
+ idr_for_each_entry(&afu->contexts_idr, ctx, tmp) {
+ /*
+ * Anything done in here needs to be setup before the IDR is
+ * created and torn down after the IDR removed
+ */
+ cxl_context_detach(ctx);
+
+ /*
+ * We are force detaching - remove any active PSA mappings so
+ * userspace cannot interfere with the card if it comes back.
+ * Easiest way to exercise this is to unbind and rebind the
+ * driver via sysfs while it is in use.
+ */
+ mutex_lock(&ctx->mapping_lock);
+ if (ctx->mapping)
+ unmap_mapping_range(ctx->mapping, 0, 0, 1);
+ mutex_unlock(&ctx->mapping_lock);
+ }
+ mutex_unlock(&afu->contexts_lock);
+}
+
+static void reclaim_ctx(struct rcu_head *rcu)
+{
+ struct cxl_context *ctx = container_of(rcu, struct cxl_context, rcu);
+
+ if (cxl_is_power8())
+ free_page((u64)ctx->sstp);
+ if (ctx->ff_page)
+ __free_page(ctx->ff_page);
+ ctx->sstp = NULL;
+
+ bitmap_free(ctx->irq_bitmap);
+
+ /* Drop ref to the afu device taken during cxl_context_init */
+ cxl_afu_put(ctx->afu);
+
+ kfree(ctx);
+}
+
+void cxl_context_free(struct cxl_context *ctx)
+{
+ if (ctx->kernelapi && ctx->mapping)
+ cxl_release_mapping(ctx);
+ mutex_lock(&ctx->afu->contexts_lock);
+ idr_remove(&ctx->afu->contexts_idr, ctx->pe);
+ mutex_unlock(&ctx->afu->contexts_lock);
+ call_rcu(&ctx->rcu, reclaim_ctx);
+}
+
+void cxl_context_mm_count_get(struct cxl_context *ctx)
+{
+ if (ctx->mm)
+ mmgrab(ctx->mm);
+}
+
+void cxl_context_mm_count_put(struct cxl_context *ctx)
+{
+ if (ctx->mm)
+ mmdrop(ctx->mm);
+}