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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 /virt/kvm/dirty_ring.c
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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 'virt/kvm/dirty_ring.c')
-rw-r--r--virt/kvm/dirty_ring.c222
1 files changed, 222 insertions, 0 deletions
diff --git a/virt/kvm/dirty_ring.c b/virt/kvm/dirty_ring.c
new file mode 100644
index 000000000..c1cd7dfe4
--- /dev/null
+++ b/virt/kvm/dirty_ring.c
@@ -0,0 +1,222 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * KVM dirty ring implementation
+ *
+ * Copyright 2019 Red Hat, Inc.
+ */
+#include <linux/kvm_host.h>
+#include <linux/kvm.h>
+#include <linux/vmalloc.h>
+#include <linux/kvm_dirty_ring.h>
+#include <trace/events/kvm.h>
+#include "kvm_mm.h"
+
+int __weak kvm_cpu_dirty_log_size(void)
+{
+ return 0;
+}
+
+u32 kvm_dirty_ring_get_rsvd_entries(void)
+{
+ return KVM_DIRTY_RING_RSVD_ENTRIES + kvm_cpu_dirty_log_size();
+}
+
+bool kvm_use_dirty_bitmap(struct kvm *kvm)
+{
+ lockdep_assert_held(&kvm->slots_lock);
+
+ return !kvm->dirty_ring_size || kvm->dirty_ring_with_bitmap;
+}
+
+#ifndef CONFIG_NEED_KVM_DIRTY_RING_WITH_BITMAP
+bool kvm_arch_allow_write_without_running_vcpu(struct kvm *kvm)
+{
+ return false;
+}
+#endif
+
+static u32 kvm_dirty_ring_used(struct kvm_dirty_ring *ring)
+{
+ return READ_ONCE(ring->dirty_index) - READ_ONCE(ring->reset_index);
+}
+
+static bool kvm_dirty_ring_soft_full(struct kvm_dirty_ring *ring)
+{
+ return kvm_dirty_ring_used(ring) >= ring->soft_limit;
+}
+
+static bool kvm_dirty_ring_full(struct kvm_dirty_ring *ring)
+{
+ return kvm_dirty_ring_used(ring) >= ring->size;
+}
+
+static void kvm_reset_dirty_gfn(struct kvm *kvm, u32 slot, u64 offset, u64 mask)
+{
+ struct kvm_memory_slot *memslot;
+ int as_id, id;
+
+ as_id = slot >> 16;
+ id = (u16)slot;
+
+ if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
+ return;
+
+ memslot = id_to_memslot(__kvm_memslots(kvm, as_id), id);
+
+ if (!memslot || (offset + __fls(mask)) >= memslot->npages)
+ return;
+
+ KVM_MMU_LOCK(kvm);
+ kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot, offset, mask);
+ KVM_MMU_UNLOCK(kvm);
+}
+
+int kvm_dirty_ring_alloc(struct kvm_dirty_ring *ring, int index, u32 size)
+{
+ ring->dirty_gfns = vzalloc(size);
+ if (!ring->dirty_gfns)
+ return -ENOMEM;
+
+ ring->size = size / sizeof(struct kvm_dirty_gfn);
+ ring->soft_limit = ring->size - kvm_dirty_ring_get_rsvd_entries();
+ ring->dirty_index = 0;
+ ring->reset_index = 0;
+ ring->index = index;
+
+ return 0;
+}
+
+static inline void kvm_dirty_gfn_set_invalid(struct kvm_dirty_gfn *gfn)
+{
+ smp_store_release(&gfn->flags, 0);
+}
+
+static inline void kvm_dirty_gfn_set_dirtied(struct kvm_dirty_gfn *gfn)
+{
+ gfn->flags = KVM_DIRTY_GFN_F_DIRTY;
+}
+
+static inline bool kvm_dirty_gfn_harvested(struct kvm_dirty_gfn *gfn)
+{
+ return smp_load_acquire(&gfn->flags) & KVM_DIRTY_GFN_F_RESET;
+}
+
+int kvm_dirty_ring_reset(struct kvm *kvm, struct kvm_dirty_ring *ring)
+{
+ u32 cur_slot, next_slot;
+ u64 cur_offset, next_offset;
+ unsigned long mask;
+ int count = 0;
+ struct kvm_dirty_gfn *entry;
+ bool first_round = true;
+
+ /* This is only needed to make compilers happy */
+ cur_slot = cur_offset = mask = 0;
+
+ while (true) {
+ entry = &ring->dirty_gfns[ring->reset_index & (ring->size - 1)];
+
+ if (!kvm_dirty_gfn_harvested(entry))
+ break;
+
+ next_slot = READ_ONCE(entry->slot);
+ next_offset = READ_ONCE(entry->offset);
+
+ /* Update the flags to reflect that this GFN is reset */
+ kvm_dirty_gfn_set_invalid(entry);
+
+ ring->reset_index++;
+ count++;
+ /*
+ * Try to coalesce the reset operations when the guest is
+ * scanning pages in the same slot.
+ */
+ if (!first_round && next_slot == cur_slot) {
+ s64 delta = next_offset - cur_offset;
+
+ if (delta >= 0 && delta < BITS_PER_LONG) {
+ mask |= 1ull << delta;
+ continue;
+ }
+
+ /* Backwards visit, careful about overflows! */
+ if (delta > -BITS_PER_LONG && delta < 0 &&
+ (mask << -delta >> -delta) == mask) {
+ cur_offset = next_offset;
+ mask = (mask << -delta) | 1;
+ continue;
+ }
+ }
+ kvm_reset_dirty_gfn(kvm, cur_slot, cur_offset, mask);
+ cur_slot = next_slot;
+ cur_offset = next_offset;
+ mask = 1;
+ first_round = false;
+ }
+
+ kvm_reset_dirty_gfn(kvm, cur_slot, cur_offset, mask);
+
+ /*
+ * The request KVM_REQ_DIRTY_RING_SOFT_FULL will be cleared
+ * by the VCPU thread next time when it enters the guest.
+ */
+
+ trace_kvm_dirty_ring_reset(ring);
+
+ return count;
+}
+
+void kvm_dirty_ring_push(struct kvm_vcpu *vcpu, u32 slot, u64 offset)
+{
+ struct kvm_dirty_ring *ring = &vcpu->dirty_ring;
+ struct kvm_dirty_gfn *entry;
+
+ /* It should never get full */
+ WARN_ON_ONCE(kvm_dirty_ring_full(ring));
+
+ entry = &ring->dirty_gfns[ring->dirty_index & (ring->size - 1)];
+
+ entry->slot = slot;
+ entry->offset = offset;
+ /*
+ * Make sure the data is filled in before we publish this to
+ * the userspace program. There's no paired kernel-side reader.
+ */
+ smp_wmb();
+ kvm_dirty_gfn_set_dirtied(entry);
+ ring->dirty_index++;
+ trace_kvm_dirty_ring_push(ring, slot, offset);
+
+ if (kvm_dirty_ring_soft_full(ring))
+ kvm_make_request(KVM_REQ_DIRTY_RING_SOFT_FULL, vcpu);
+}
+
+bool kvm_dirty_ring_check_request(struct kvm_vcpu *vcpu)
+{
+ /*
+ * The VCPU isn't runnable when the dirty ring becomes soft full.
+ * The KVM_REQ_DIRTY_RING_SOFT_FULL event is always set to prevent
+ * the VCPU from running until the dirty pages are harvested and
+ * the dirty ring is reset by userspace.
+ */
+ if (kvm_check_request(KVM_REQ_DIRTY_RING_SOFT_FULL, vcpu) &&
+ kvm_dirty_ring_soft_full(&vcpu->dirty_ring)) {
+ kvm_make_request(KVM_REQ_DIRTY_RING_SOFT_FULL, vcpu);
+ vcpu->run->exit_reason = KVM_EXIT_DIRTY_RING_FULL;
+ trace_kvm_dirty_ring_exit(vcpu);
+ return true;
+ }
+
+ return false;
+}
+
+struct page *kvm_dirty_ring_get_page(struct kvm_dirty_ring *ring, u32 offset)
+{
+ return vmalloc_to_page((void *)ring->dirty_gfns + offset * PAGE_SIZE);
+}
+
+void kvm_dirty_ring_free(struct kvm_dirty_ring *ring)
+{
+ vfree(ring->dirty_gfns);
+ ring->dirty_gfns = NULL;
+}