For pseries machine emulation, in order to move the interrupt controller code to the kernel, we need to intercept some RTAS calls in the kernel itself
Signed-off-by: Michael Ellerman <[email protected]> Signed-off-by: Benjamin Herrenschmidt <[email protected]> --- arch/powerpc/include/asm/hvcall.h | 3 + arch/powerpc/include/asm/kvm.h | 6 ++ arch/powerpc/include/asm/kvm_host.h | 1 + arch/powerpc/include/asm/kvm_ppc.h | 4 + arch/powerpc/kvm/Makefile | 1 + arch/powerpc/kvm/book3s_hv.c | 17 ++++ arch/powerpc/kvm/book3s_pr_papr.c | 8 ++ arch/powerpc/kvm/book3s_rtas.c | 182 +++++++++++++++++++++++++++++++++++ arch/powerpc/kvm/powerpc.c | 9 +- include/linux/kvm.h | 3 + 10 files changed, 232 insertions(+), 2 deletions(-) create mode 100644 arch/powerpc/kvm/book3s_rtas.c diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h index 423cf9e..f46c0a0 100644 --- a/arch/powerpc/include/asm/hvcall.h +++ b/arch/powerpc/include/asm/hvcall.h @@ -274,6 +274,9 @@ #define H_GET_MPP_X 0x314 #define MAX_HCALL_OPCODE H_GET_MPP_X +/* Platform specific hcalls, used by KVM */ +#define H_RTAS 0xf000 + #ifndef __ASSEMBLY__ /** diff --git a/arch/powerpc/include/asm/kvm.h b/arch/powerpc/include/asm/kvm.h index 1bea4d8..3dc91df 100644 --- a/arch/powerpc/include/asm/kvm.h +++ b/arch/powerpc/include/asm/kvm.h @@ -290,6 +290,12 @@ struct kvm_allocate_rma { __u64 rma_size; }; +/* for KVM_CAP_PPC_RTAS */ +struct kvm_rtas_token_args { + char name[120]; + __u64 token; /* Use a token of 0 to undefine a mapping */ +}; + struct kvm_book3e_206_tlb_entry { __u32 mas8; __u32 mas1; diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 50ea12f..d9c3f63 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -250,6 +250,7 @@ struct kvm_arch { #endif /* CONFIG_KVM_BOOK3S_64_HV */ #ifdef CONFIG_PPC_BOOK3S_64 struct list_head spapr_tce_tables; + struct list_head rtas_tokens; #endif }; diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index a288bec..e23bfc6 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -149,6 +149,10 @@ extern int kvm_vm_ioctl_get_smmu_info(struct kvm *kvm, extern int kvmppc_bookehv_init(void); extern void kvmppc_bookehv_exit(void); +extern int kvm_vm_ioctl_rtas_define_token(struct kvm *kvm, void __user *argp); +extern int kvmppc_rtas_hcall(struct kvm_vcpu *vcpu); +extern void kvmppc_rtas_tokens_free(struct kvm *kvm); + /* * Cuts out inst bits with ordering according to spec. * That means the leftmost bit is zero. All given bits are included. diff --git a/arch/powerpc/kvm/Makefile b/arch/powerpc/kvm/Makefile index c2a0863..536f65f 100644 --- a/arch/powerpc/kvm/Makefile +++ b/arch/powerpc/kvm/Makefile @@ -80,6 +80,7 @@ kvm-book3s_64-module-objs := \ emulate.o \ book3s.o \ book3s_64_vio.o \ + book3s_rtas.o \ $(kvm-book3s_64-objs-y) kvm-objs-$(CONFIG_KVM_BOOK3S_64) := $(kvm-book3s_64-module-objs) diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 257e05b..6199063 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -418,6 +418,7 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu) unsigned long req = kvmppc_get_gpr(vcpu, 3); unsigned long target, ret = H_SUCCESS; struct kvm_vcpu *tvcpu; + int rc; switch (req) { case H_ENTER: @@ -451,6 +452,19 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu) kvmppc_get_gpr(vcpu, 5), kvmppc_get_gpr(vcpu, 6)); break; + case H_RTAS: + if (list_empty(&vcpu->kvm->arch.rtas_tokens)) + return RESUME_HOST; + + rc = kvmppc_rtas_hcall(vcpu); + + if (rc == -ENOENT) + return RESUME_HOST; + else if (rc == 0) + break; + + /* Send the error out to userspace via KVM_RUN */ + return rc; default: return RESUME_HOST; } @@ -1543,6 +1557,7 @@ int kvmppc_core_init_vm(struct kvm *kvm) kvm->arch.lpid = lpid; INIT_LIST_HEAD(&kvm->arch.spapr_tce_tables); + INIT_LIST_HEAD(&kvm->arch.rtas_tokens); kvm->arch.rma = NULL; @@ -1585,6 +1600,8 @@ void kvmppc_core_destroy_vm(struct kvm *kvm) kvm->arch.rma = NULL; } + kvmppc_rtas_tokens_free(kvm); + kvmppc_free_hpt(kvm); WARN_ON(!list_empty(&kvm->arch.spapr_tce_tables)); } diff --git a/arch/powerpc/kvm/book3s_pr_papr.c b/arch/powerpc/kvm/book3s_pr_papr.c index ee02b30..175404a 100644 --- a/arch/powerpc/kvm/book3s_pr_papr.c +++ b/arch/powerpc/kvm/book3s_pr_papr.c @@ -246,6 +246,14 @@ int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd) clear_bit(KVM_REQ_UNHALT, &vcpu->requests); vcpu->stat.halt_wakeup++; return EMULATE_DONE; + case H_RTAS: + if (list_empty(&vcpu->kvm->arch.rtas_tokens)) + return RESUME_HOST; + rc = kvmppc_rtas_hcall(vcpu); + if (rc != 0) + break; + kvmppc_set_gpr(vcpu, 3, 0); + return EMULATE_DONE; } return EMULATE_FAIL; diff --git a/arch/powerpc/kvm/book3s_rtas.c b/arch/powerpc/kvm/book3s_rtas.c new file mode 100644 index 0000000..8a324e8 --- /dev/null +++ b/arch/powerpc/kvm/book3s_rtas.c @@ -0,0 +1,182 @@ +/* + * Copyright 2012 Michael Ellerman, IBM Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/kvm_host.h> +#include <linux/kvm.h> +#include <linux/err.h> + +#include <asm/uaccess.h> +#include <asm/kvm_book3s.h> +#include <asm/kvm_ppc.h> +#include <asm/hvcall.h> +#include <asm/rtas.h> + + +struct rtas_handler { + void (*handler)(struct kvm_vcpu *vcpu, struct rtas_args *args); + char *name; +}; + +static struct rtas_handler rtas_handlers[] = { }; + +struct rtas_token_definition { + struct list_head list; + struct rtas_handler *handler; + u64 token; +}; + +static int rtas_name_matches(char *s1, char *s2) +{ + struct kvm_rtas_token_args args; + return !strncmp(s1, s2, sizeof(args.name)); +} + +static int rtas_token_undefine(struct kvm *kvm, char *name) +{ + struct rtas_token_definition *d, *tmp; + + lockdep_assert_held(&kvm->lock); + + list_for_each_entry_safe(d, tmp, &kvm->arch.rtas_tokens, list) { + if (rtas_name_matches(d->handler->name, name)) { + list_del(&d->list); + kfree(d); + return 0; + } + } + + /* It's not an error to undefine an undefined token */ + return 0; +} + +static int rtas_token_define(struct kvm *kvm, char *name, u64 token) +{ + struct rtas_token_definition *d; + struct rtas_handler *h; + bool found; + int i; + + lockdep_assert_held(&kvm->lock); + + list_for_each_entry(d, &kvm->arch.rtas_tokens, list) { + if (d->token == token) + return -EEXIST; + } + + found = false; + for (i = 0; i < ARRAY_SIZE(rtas_handlers); i++) { + h = &rtas_handlers[i]; + if (rtas_name_matches(h->name, name)) { + found = true; + break; + } + } + + if (!found) + return -ENOENT; + + d = kzalloc(sizeof(*d), GFP_KERNEL); + if (!d) + return -ENOMEM; + + d->handler = h; + d->token = token; + + list_add_tail(&d->list, &kvm->arch.rtas_tokens); + + return 0; +} + +int kvm_vm_ioctl_rtas_define_token(struct kvm *kvm, void __user *argp) +{ + struct kvm_rtas_token_args args; + int rc; + + if (copy_from_user(&args, argp, sizeof(args))) + return -EFAULT; + + mutex_lock(&kvm->lock); + + if (args.token) + rc = rtas_token_define(kvm, args.name, args.token); + else + rc = rtas_token_undefine(kvm, args.name); + + mutex_unlock(&kvm->lock); + + return rc; +} + +int kvmppc_rtas_hcall(struct kvm_vcpu *vcpu) +{ + struct rtas_token_definition *d; + struct rtas_args args; + rtas_arg_t *orig_rets; + gpa_t args_phys; + int rc; + + /* r4 contains the guest physical address of the RTAS args */ + args_phys = kvmppc_get_gpr(vcpu, 4); + + rc = kvm_read_guest(vcpu->kvm, args_phys, &args, sizeof(args)); + if (rc) + goto fail; + + /* + * args->rets is a pointer into args->args. Now that we've + * copied args we need to fix it up to point into our copy, + * not the guest args. We also need to save the original + * value so we can restore it on the way out. + */ + orig_rets = args.rets; + args.rets = &args.args[args.nargs]; + + mutex_lock(&vcpu->kvm->lock); + + rc = -ENOENT; + list_for_each_entry(d, &vcpu->kvm->arch.rtas_tokens, list) { + if (d->token == args.token) { + d->handler->handler(vcpu, &args); + rc = 0; + break; + } + } + + mutex_unlock(&vcpu->kvm->lock); + + if (rc == 0) { + args.rets = orig_rets; + rc = kvm_write_guest(vcpu->kvm, args_phys, &args, sizeof(args)); + if (rc) + goto fail; + } + + return rc; + +fail: + /* + * We only get here if the guest has called RTAS with a bogus + * args pointer. That means we can't get to the args, and so we + * can't fail the RTAS call. So fail right out to userspace, + * which should kill the guest. + */ + return rc; +} + +void kvmppc_rtas_tokens_free(struct kvm *kvm) +{ + struct rtas_token_definition *d, *tmp; + + lockdep_assert_held(&kvm->lock); + + list_for_each_entry_safe(d, tmp, &kvm->arch.rtas_tokens, list) { + list_del(&d->list); + kfree(d); + } +} diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index b54aaa8..4b7522f 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -247,6 +247,7 @@ int kvm_dev_ioctl_check_extension(long ext) #ifdef CONFIG_PPC_BOOK3S_64 case KVM_CAP_SPAPR_TCE: case KVM_CAP_PPC_ALLOC_HTAB: + case KVM_CAP_PPC_RTAS: r = 1; break; #endif /* CONFIG_PPC_BOOK3S_64 */ @@ -787,6 +788,7 @@ long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { void __user *argp = (void __user *)arg; + struct kvm *kvm = filp->private_data; long r; switch (ioctl) { @@ -804,7 +806,6 @@ long kvm_arch_vm_ioctl(struct file *filp, #ifdef CONFIG_PPC_BOOK3S_64 case KVM_CREATE_SPAPR_TCE: { struct kvm_create_spapr_tce create_tce; - struct kvm *kvm = filp->private_data; r = -EFAULT; if (copy_from_user(&create_tce, argp, sizeof(create_tce))) @@ -816,7 +817,6 @@ long kvm_arch_vm_ioctl(struct file *filp, #ifdef CONFIG_KVM_BOOK3S_64_HV case KVM_ALLOCATE_RMA: { - struct kvm *kvm = filp->private_data; struct kvm_allocate_rma rma; r = kvm_vm_ioctl_allocate_rma(kvm, &rma); @@ -841,6 +841,11 @@ long kvm_arch_vm_ioctl(struct file *filp, r = 0; break; } + + case KVM_PPC_RTAS_DEFINE_TOKEN: + r = kvm_vm_ioctl_rtas_define_token(kvm, argp); + break; + #endif /* CONFIG_KVM_BOOK3S_64_HV */ #ifdef CONFIG_PPC_BOOK3S_64 diff --git a/include/linux/kvm.h b/include/linux/kvm.h index 2917f0e..35c063a 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -619,6 +619,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_S390_COW 79 #define KVM_CAP_PPC_ALLOC_HTAB 80 #define KVM_CAP_PPC_VPA 81 +#define KVM_CAP_PPC_RTAS 82 #ifdef KVM_CAP_IRQ_ROUTING @@ -832,6 +833,8 @@ struct kvm_s390_ucas_mapping { #define KVM_PPC_GET_SMMU_INFO _IOR(KVMIO, 0xa6, struct kvm_ppc_smmu_info) /* Available with KVM_CAP_PPC_ALLOC_HTAB */ #define KVM_PPC_ALLOCATE_HTAB _IOWR(KVMIO, 0xa7, __u32) +/* Available with KVM_CAP_PPC_RTAS */ +#define KVM_PPC_RTAS_DEFINE_TOKEN _IOW(KVMIO, 0xa8, struct kvm_rtas_token_args) /* * ioctls for vcpu fds -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
