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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 /arch/powerpc/kvm/tm.S
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 'arch/powerpc/kvm/tm.S')
-rw-r--r--arch/powerpc/kvm/tm.S398
1 files changed, 398 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/tm.S b/arch/powerpc/kvm/tm.S
new file mode 100644
index 000000000..2158f61e3
--- /dev/null
+++ b/arch/powerpc/kvm/tm.S
@@ -0,0 +1,398 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ *
+ * Derived from book3s_hv_rmhandlers.S, which is:
+ *
+ * Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
+ */
+
+#include <asm/reg.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/export.h>
+#include <asm/tm.h>
+#include <asm/cputable.h>
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+#define VCPU_GPRS_TM(reg) (((reg) * ULONG_SIZE) + VCPU_GPR_TM)
+
+/*
+ * Save transactional state and TM-related registers.
+ * Called with:
+ * - r3 pointing to the vcpu struct
+ * - r4 containing the MSR with current TS bits:
+ * (For HV KVM, it is VCPU_MSR ; For PR KVM, it is host MSR).
+ * - r5 containing a flag indicating that non-volatile registers
+ * must be preserved.
+ * If r5 == 0, this can modify all checkpointed registers, but
+ * restores r1, r2 before exit. If r5 != 0, this restores the
+ * MSR TM/FP/VEC/VSX bits to their state on entry.
+ */
+_GLOBAL(__kvmppc_save_tm)
+ mflr r0
+ std r0, PPC_LR_STKOFF(r1)
+ stdu r1, -SWITCH_FRAME_SIZE(r1)
+
+ mr r9, r3
+ cmpdi cr7, r5, 0
+
+ /* Turn on TM. */
+ mfmsr r8
+ mr r10, r8
+ li r0, 1
+ rldimi r8, r0, MSR_TM_LG, 63-MSR_TM_LG
+ ori r8, r8, MSR_FP
+ oris r8, r8, (MSR_VEC | MSR_VSX)@h
+ mtmsrd r8
+
+ rldicl. r4, r4, 64 - MSR_TS_S_LG, 62
+ beq 1f /* TM not active in guest. */
+
+ std r1, HSTATE_SCRATCH2(r13)
+ std r3, HSTATE_SCRATCH1(r13)
+
+ /* Save CR on the stack - even if r5 == 0 we need to get cr7 back. */
+ mfcr r6
+ SAVE_GPR(6, r1)
+
+ /* Save DSCR so we can restore it to avoid running with user value */
+ mfspr r7, SPRN_DSCR
+ SAVE_GPR(7, r1)
+
+ /*
+ * We are going to do treclaim., which will modify all checkpointed
+ * registers. Save the non-volatile registers on the stack if
+ * preservation of non-volatile state has been requested.
+ */
+ beq cr7, 3f
+ SAVE_NVGPRS(r1)
+
+ /* MSR[TS] will be 0 (non-transactional) once we do treclaim. */
+ li r0, 0
+ rldimi r10, r0, MSR_TS_S_LG, 63 - MSR_TS_T_LG
+ SAVE_GPR(10, r1) /* final MSR value */
+3:
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+BEGIN_FTR_SECTION
+ /* Emulation of the treclaim instruction needs TEXASR before treclaim */
+ mfspr r6, SPRN_TEXASR
+ std r6, VCPU_ORIG_TEXASR(r3)
+END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_HV_ASSIST)
+#endif
+
+ /* Clear the MSR RI since r1, r13 are all going to be foobar. */
+ li r5, 0
+ mtmsrd r5, 1
+
+ li r3, TM_CAUSE_KVM_RESCHED
+
+ /* All GPRs are volatile at this point. */
+ TRECLAIM(R3)
+
+ /* Temporarily store r13 and r9 so we have some regs to play with */
+ SET_SCRATCH0(r13)
+ GET_PACA(r13)
+ std r9, PACATMSCRATCH(r13)
+ ld r9, HSTATE_SCRATCH1(r13)
+
+ /* Save away PPR soon so we don't run with user value. */
+ std r0, VCPU_GPRS_TM(0)(r9)
+ mfspr r0, SPRN_PPR
+ HMT_MEDIUM
+
+ /* Reload stack pointer. */
+ std r1, VCPU_GPRS_TM(1)(r9)
+ ld r1, HSTATE_SCRATCH2(r13)
+
+ /* Set MSR RI now we have r1 and r13 back. */
+ std r2, VCPU_GPRS_TM(2)(r9)
+ li r2, MSR_RI
+ mtmsrd r2, 1
+
+ /* Reload TOC pointer. */
+ LOAD_PACA_TOC()
+
+ /* Save all but r0-r2, r9 & r13 */
+ reg = 3
+ .rept 29
+ .if (reg != 9) && (reg != 13)
+ std reg, VCPU_GPRS_TM(reg)(r9)
+ .endif
+ reg = reg + 1
+ .endr
+ /* ... now save r13 */
+ GET_SCRATCH0(r4)
+ std r4, VCPU_GPRS_TM(13)(r9)
+ /* ... and save r9 */
+ ld r4, PACATMSCRATCH(r13)
+ std r4, VCPU_GPRS_TM(9)(r9)
+
+ /* Restore host DSCR and CR values, after saving guest values */
+ mfcr r6
+ mfspr r7, SPRN_DSCR
+ stw r6, VCPU_CR_TM(r9)
+ std r7, VCPU_DSCR_TM(r9)
+ REST_GPR(6, r1)
+ REST_GPR(7, r1)
+ mtcr r6
+ mtspr SPRN_DSCR, r7
+
+ /* Save away checkpointed SPRs. */
+ std r0, VCPU_PPR_TM(r9)
+ mflr r5
+ mfctr r7
+ mfspr r8, SPRN_AMR
+ mfspr r10, SPRN_TAR
+ mfxer r11
+ std r5, VCPU_LR_TM(r9)
+ std r7, VCPU_CTR_TM(r9)
+ std r8, VCPU_AMR_TM(r9)
+ std r10, VCPU_TAR_TM(r9)
+ std r11, VCPU_XER_TM(r9)
+
+ /* Save FP/VSX. */
+ addi r3, r9, VCPU_FPRS_TM
+ bl store_fp_state
+ addi r3, r9, VCPU_VRS_TM
+ bl store_vr_state
+ mfspr r6, SPRN_VRSAVE
+ stw r6, VCPU_VRSAVE_TM(r9)
+
+ /* Restore non-volatile registers if requested to */
+ beq cr7, 1f
+ REST_NVGPRS(r1)
+ REST_GPR(10, r1)
+1:
+ /*
+ * We need to save these SPRs after the treclaim so that the software
+ * error code is recorded correctly in the TEXASR. Also the user may
+ * change these outside of a transaction, so they must always be
+ * context switched.
+ */
+ mfspr r7, SPRN_TEXASR
+ std r7, VCPU_TEXASR(r9)
+ mfspr r5, SPRN_TFHAR
+ mfspr r6, SPRN_TFIAR
+ std r5, VCPU_TFHAR(r9)
+ std r6, VCPU_TFIAR(r9)
+
+ /* Restore MSR state if requested */
+ beq cr7, 2f
+ mtmsrd r10, 0
+2:
+ addi r1, r1, SWITCH_FRAME_SIZE
+ ld r0, PPC_LR_STKOFF(r1)
+ mtlr r0
+ blr
+
+/*
+ * _kvmppc_save_tm_pr() is a wrapper around __kvmppc_save_tm(), so that it can
+ * be invoked from C function by PR KVM only.
+ */
+_GLOBAL(_kvmppc_save_tm_pr)
+ mflr r0
+ std r0, PPC_LR_STKOFF(r1)
+ stdu r1, -PPC_MIN_STKFRM(r1)
+
+ mfspr r8, SPRN_TAR
+ std r8, PPC_MIN_STKFRM-8(r1)
+
+ li r5, 1 /* preserve non-volatile registers */
+ bl __kvmppc_save_tm
+
+ ld r8, PPC_MIN_STKFRM-8(r1)
+ mtspr SPRN_TAR, r8
+
+ addi r1, r1, PPC_MIN_STKFRM
+ ld r0, PPC_LR_STKOFF(r1)
+ mtlr r0
+ blr
+
+EXPORT_SYMBOL_GPL(_kvmppc_save_tm_pr);
+
+/*
+ * Restore transactional state and TM-related registers.
+ * Called with:
+ * - r3 pointing to the vcpu struct.
+ * - r4 is the guest MSR with desired TS bits:
+ * For HV KVM, it is VCPU_MSR
+ * For PR KVM, it is provided by caller
+ * - r5 containing a flag indicating that non-volatile registers
+ * must be preserved.
+ * If r5 == 0, this potentially modifies all checkpointed registers, but
+ * restores r1, r2 from the PACA before exit.
+ * If r5 != 0, this restores the MSR TM/FP/VEC/VSX bits to their state on entry.
+ */
+_GLOBAL(__kvmppc_restore_tm)
+ mflr r0
+ std r0, PPC_LR_STKOFF(r1)
+
+ cmpdi cr7, r5, 0
+
+ /* Turn on TM/FP/VSX/VMX so we can restore them. */
+ mfmsr r5
+ mr r10, r5
+ li r6, MSR_TM >> 32
+ sldi r6, r6, 32
+ or r5, r5, r6
+ ori r5, r5, MSR_FP
+ oris r5, r5, (MSR_VEC | MSR_VSX)@h
+ mtmsrd r5
+
+ /*
+ * The user may change these outside of a transaction, so they must
+ * always be context switched.
+ */
+ ld r5, VCPU_TFHAR(r3)
+ ld r6, VCPU_TFIAR(r3)
+ ld r7, VCPU_TEXASR(r3)
+ mtspr SPRN_TFHAR, r5
+ mtspr SPRN_TFIAR, r6
+ mtspr SPRN_TEXASR, r7
+
+ mr r5, r4
+ rldicl. r5, r5, 64 - MSR_TS_S_LG, 62
+ beq 9f /* TM not active in guest */
+
+ /* Make sure the failure summary is set, otherwise we'll program check
+ * when we trechkpt. It's possible that this might have been not set
+ * on a kvmppc_set_one_reg() call but we shouldn't let this crash the
+ * host.
+ */
+ oris r7, r7, (TEXASR_FS)@h
+ mtspr SPRN_TEXASR, r7
+
+ /*
+ * Make a stack frame and save non-volatile registers if requested.
+ */
+ stdu r1, -SWITCH_FRAME_SIZE(r1)
+ std r1, HSTATE_SCRATCH2(r13)
+
+ mfcr r6
+ mfspr r7, SPRN_DSCR
+ SAVE_GPR(2, r1)
+ SAVE_GPR(6, r1)
+ SAVE_GPR(7, r1)
+
+ beq cr7, 4f
+ SAVE_NVGPRS(r1)
+
+ /* MSR[TS] will be 1 (suspended) once we do trechkpt */
+ li r0, 1
+ rldimi r10, r0, MSR_TS_S_LG, 63 - MSR_TS_T_LG
+ SAVE_GPR(10, r1) /* final MSR value */
+4:
+ /*
+ * We need to load up the checkpointed state for the guest.
+ * We need to do this early as it will blow away any GPRs, VSRs and
+ * some SPRs.
+ */
+
+ mr r31, r3
+ addi r3, r31, VCPU_FPRS_TM
+ bl load_fp_state
+ addi r3, r31, VCPU_VRS_TM
+ bl load_vr_state
+ mr r3, r31
+ lwz r7, VCPU_VRSAVE_TM(r3)
+ mtspr SPRN_VRSAVE, r7
+
+ ld r5, VCPU_LR_TM(r3)
+ lwz r6, VCPU_CR_TM(r3)
+ ld r7, VCPU_CTR_TM(r3)
+ ld r8, VCPU_AMR_TM(r3)
+ ld r9, VCPU_TAR_TM(r3)
+ ld r10, VCPU_XER_TM(r3)
+ mtlr r5
+ mtcr r6
+ mtctr r7
+ mtspr SPRN_AMR, r8
+ mtspr SPRN_TAR, r9
+ mtxer r10
+
+ /*
+ * Load up PPR and DSCR values but don't put them in the actual SPRs
+ * till the last moment to avoid running with userspace PPR and DSCR for
+ * too long.
+ */
+ ld r29, VCPU_DSCR_TM(r3)
+ ld r30, VCPU_PPR_TM(r3)
+
+ /* Clear the MSR RI since r1, r13 are all going to be foobar. */
+ li r5, 0
+ mtmsrd r5, 1
+
+ /* Load GPRs r0-r28 */
+ reg = 0
+ .rept 29
+ ld reg, VCPU_GPRS_TM(reg)(r31)
+ reg = reg + 1
+ .endr
+
+ mtspr SPRN_DSCR, r29
+ mtspr SPRN_PPR, r30
+
+ /* Load final GPRs */
+ ld 29, VCPU_GPRS_TM(29)(r31)
+ ld 30, VCPU_GPRS_TM(30)(r31)
+ ld 31, VCPU_GPRS_TM(31)(r31)
+
+ /* TM checkpointed state is now setup. All GPRs are now volatile. */
+ TRECHKPT
+
+ /* Now let's get back the state we need. */
+ HMT_MEDIUM
+ GET_PACA(r13)
+ ld r1, HSTATE_SCRATCH2(r13)
+ REST_GPR(7, r1)
+ mtspr SPRN_DSCR, r7
+
+ /* Set the MSR RI since we have our registers back. */
+ li r5, MSR_RI
+ mtmsrd r5, 1
+
+ /* Restore TOC pointer and CR */
+ REST_GPR(2, r1)
+ REST_GPR(6, r1)
+ mtcr r6
+
+ /* Restore non-volatile registers if requested to. */
+ beq cr7, 5f
+ REST_GPR(10, r1)
+ REST_NVGPRS(r1)
+
+5: addi r1, r1, SWITCH_FRAME_SIZE
+ ld r0, PPC_LR_STKOFF(r1)
+ mtlr r0
+
+9: /* Restore MSR bits if requested */
+ beqlr cr7
+ mtmsrd r10, 0
+ blr
+
+/*
+ * _kvmppc_restore_tm_pr() is a wrapper around __kvmppc_restore_tm(), so that it
+ * can be invoked from C function by PR KVM only.
+ */
+_GLOBAL(_kvmppc_restore_tm_pr)
+ mflr r0
+ std r0, PPC_LR_STKOFF(r1)
+ stdu r1, -PPC_MIN_STKFRM(r1)
+
+ /* save TAR so that it can be recovered later */
+ mfspr r8, SPRN_TAR
+ std r8, PPC_MIN_STKFRM-8(r1)
+
+ li r5, 1
+ bl __kvmppc_restore_tm
+
+ ld r8, PPC_MIN_STKFRM-8(r1)
+ mtspr SPRN_TAR, r8
+
+ addi r1, r1, PPC_MIN_STKFRM
+ ld r0, PPC_LR_STKOFF(r1)
+ mtlr r0
+ blr
+
+EXPORT_SYMBOL_GPL(_kvmppc_restore_tm_pr);
+#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */