linux/arch/powerpc/kvm/book3s_pr_papr.c

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/*
* Copyright (C) 2011. Freescale Inc. All rights reserved.
*
* Authors:
* Alexander Graf <agraf@suse.de>
* Paul Mackerras <paulus@samba.org>
*
* Description:
*
* Hypercall handling for running PAPR guests in PR KVM on Book 3S
* processors.
*
* 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/anon_inodes.h>
#include <linux/uaccess.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>
#define HPTE_SIZE 16 /* bytes per HPT entry */
static unsigned long get_pteg_addr(struct kvm_vcpu *vcpu, long pte_index)
{
struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
unsigned long pteg_addr;
pte_index <<= 4;
pte_index &= ((1 << ((vcpu_book3s->sdr1 & 0x1f) + 11)) - 1) << 7 | 0x70;
pteg_addr = vcpu_book3s->sdr1 & 0xfffffffffffc0000ULL;
pteg_addr |= pte_index;
return pteg_addr;
}
static int kvmppc_h_pr_enter(struct kvm_vcpu *vcpu)
{
long flags = kvmppc_get_gpr(vcpu, 4);
long pte_index = kvmppc_get_gpr(vcpu, 5);
__be64 pteg[2 * 8];
__be64 *hpte;
unsigned long pteg_addr, i;
long int ret;
i = pte_index & 7;
pte_index &= ~7UL;
pteg_addr = get_pteg_addr(vcpu, pte_index);
mutex_lock(&vcpu->kvm->arch.hpt_mutex);
KVM: PPC: Book3S PR: Check copy_to/from_user return values The PR KVM implementation of the PAPR HPT hypercalls (H_ENTER etc.) access an image of the HPT in userspace memory using copy_from_user and copy_to_user. Recently, the declarations of those functions were annotated to indicate that the return value must be checked. Since this code doesn't currently check the return value, this causes compile warnings like the ones shown below, and since on PPC the default is to compile arch/powerpc with -Werror, this causes the build to fail. To fix this, we check the return values, and if non-zero, fail the hypercall being processed with a H_FUNCTION error return value. There is really no good error return value to use since PAPR didn't envisage the possibility that the hypervisor may not be able to access the guest's HPT, and H_FUNCTION (function not supported) seems as good as any. The typical compile warnings look like this: CC arch/powerpc/kvm/book3s_pr_papr.o /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c: In function ‘kvmppc_h_pr_enter’: /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:53:2: error: ignoring return value of ‘copy_from_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg)); ^ /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:74:2: error: ignoring return value of ‘copy_to_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_to_user((void __user *)pteg_addr, hpte, HPTE_SIZE); ^ ... etc. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-05-11 09:33:30 +08:00
ret = H_FUNCTION;
if (copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg)))
goto done;
hpte = pteg;
ret = H_PTEG_FULL;
if (likely((flags & H_EXACT) == 0)) {
for (i = 0; ; ++i) {
if (i == 8)
goto done;
if ((be64_to_cpu(*hpte) & HPTE_V_VALID) == 0)
break;
hpte += 2;
}
} else {
hpte += i * 2;
if (*hpte & HPTE_V_VALID)
goto done;
}
hpte[0] = cpu_to_be64(kvmppc_get_gpr(vcpu, 6));
hpte[1] = cpu_to_be64(kvmppc_get_gpr(vcpu, 7));
pteg_addr += i * HPTE_SIZE;
KVM: PPC: Book3S PR: Check copy_to/from_user return values The PR KVM implementation of the PAPR HPT hypercalls (H_ENTER etc.) access an image of the HPT in userspace memory using copy_from_user and copy_to_user. Recently, the declarations of those functions were annotated to indicate that the return value must be checked. Since this code doesn't currently check the return value, this causes compile warnings like the ones shown below, and since on PPC the default is to compile arch/powerpc with -Werror, this causes the build to fail. To fix this, we check the return values, and if non-zero, fail the hypercall being processed with a H_FUNCTION error return value. There is really no good error return value to use since PAPR didn't envisage the possibility that the hypervisor may not be able to access the guest's HPT, and H_FUNCTION (function not supported) seems as good as any. The typical compile warnings look like this: CC arch/powerpc/kvm/book3s_pr_papr.o /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c: In function ‘kvmppc_h_pr_enter’: /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:53:2: error: ignoring return value of ‘copy_from_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg)); ^ /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:74:2: error: ignoring return value of ‘copy_to_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_to_user((void __user *)pteg_addr, hpte, HPTE_SIZE); ^ ... etc. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-05-11 09:33:30 +08:00
ret = H_FUNCTION;
if (copy_to_user((void __user *)pteg_addr, hpte, HPTE_SIZE))
goto done;
kvmppc_set_gpr(vcpu, 4, pte_index | i);
ret = H_SUCCESS;
done:
mutex_unlock(&vcpu->kvm->arch.hpt_mutex);
kvmppc_set_gpr(vcpu, 3, ret);
return EMULATE_DONE;
}
static int kvmppc_h_pr_remove(struct kvm_vcpu *vcpu)
{
unsigned long flags= kvmppc_get_gpr(vcpu, 4);
unsigned long pte_index = kvmppc_get_gpr(vcpu, 5);
unsigned long avpn = kvmppc_get_gpr(vcpu, 6);
unsigned long v = 0, pteg, rb;
unsigned long pte[2];
long int ret;
pteg = get_pteg_addr(vcpu, pte_index);
mutex_lock(&vcpu->kvm->arch.hpt_mutex);
KVM: PPC: Book3S PR: Check copy_to/from_user return values The PR KVM implementation of the PAPR HPT hypercalls (H_ENTER etc.) access an image of the HPT in userspace memory using copy_from_user and copy_to_user. Recently, the declarations of those functions were annotated to indicate that the return value must be checked. Since this code doesn't currently check the return value, this causes compile warnings like the ones shown below, and since on PPC the default is to compile arch/powerpc with -Werror, this causes the build to fail. To fix this, we check the return values, and if non-zero, fail the hypercall being processed with a H_FUNCTION error return value. There is really no good error return value to use since PAPR didn't envisage the possibility that the hypervisor may not be able to access the guest's HPT, and H_FUNCTION (function not supported) seems as good as any. The typical compile warnings look like this: CC arch/powerpc/kvm/book3s_pr_papr.o /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c: In function ‘kvmppc_h_pr_enter’: /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:53:2: error: ignoring return value of ‘copy_from_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg)); ^ /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:74:2: error: ignoring return value of ‘copy_to_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_to_user((void __user *)pteg_addr, hpte, HPTE_SIZE); ^ ... etc. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-05-11 09:33:30 +08:00
ret = H_FUNCTION;
if (copy_from_user(pte, (void __user *)pteg, sizeof(pte)))
goto done;
pte[0] = be64_to_cpu((__force __be64)pte[0]);
pte[1] = be64_to_cpu((__force __be64)pte[1]);
ret = H_NOT_FOUND;
if ((pte[0] & HPTE_V_VALID) == 0 ||
((flags & H_AVPN) && (pte[0] & ~0x7fUL) != avpn) ||
((flags & H_ANDCOND) && (pte[0] & avpn) != 0))
goto done;
KVM: PPC: Book3S PR: Check copy_to/from_user return values The PR KVM implementation of the PAPR HPT hypercalls (H_ENTER etc.) access an image of the HPT in userspace memory using copy_from_user and copy_to_user. Recently, the declarations of those functions were annotated to indicate that the return value must be checked. Since this code doesn't currently check the return value, this causes compile warnings like the ones shown below, and since on PPC the default is to compile arch/powerpc with -Werror, this causes the build to fail. To fix this, we check the return values, and if non-zero, fail the hypercall being processed with a H_FUNCTION error return value. There is really no good error return value to use since PAPR didn't envisage the possibility that the hypervisor may not be able to access the guest's HPT, and H_FUNCTION (function not supported) seems as good as any. The typical compile warnings look like this: CC arch/powerpc/kvm/book3s_pr_papr.o /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c: In function ‘kvmppc_h_pr_enter’: /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:53:2: error: ignoring return value of ‘copy_from_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg)); ^ /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:74:2: error: ignoring return value of ‘copy_to_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_to_user((void __user *)pteg_addr, hpte, HPTE_SIZE); ^ ... etc. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-05-11 09:33:30 +08:00
ret = H_FUNCTION;
if (copy_to_user((void __user *)pteg, &v, sizeof(v)))
goto done;
rb = compute_tlbie_rb(pte[0], pte[1], pte_index);
vcpu->arch.mmu.tlbie(vcpu, rb, rb & 1 ? true : false);
ret = H_SUCCESS;
kvmppc_set_gpr(vcpu, 4, pte[0]);
kvmppc_set_gpr(vcpu, 5, pte[1]);
done:
mutex_unlock(&vcpu->kvm->arch.hpt_mutex);
kvmppc_set_gpr(vcpu, 3, ret);
return EMULATE_DONE;
}
/* Request defs for kvmppc_h_pr_bulk_remove() */
#define H_BULK_REMOVE_TYPE 0xc000000000000000ULL
#define H_BULK_REMOVE_REQUEST 0x4000000000000000ULL
#define H_BULK_REMOVE_RESPONSE 0x8000000000000000ULL
#define H_BULK_REMOVE_END 0xc000000000000000ULL
#define H_BULK_REMOVE_CODE 0x3000000000000000ULL
#define H_BULK_REMOVE_SUCCESS 0x0000000000000000ULL
#define H_BULK_REMOVE_NOT_FOUND 0x1000000000000000ULL
#define H_BULK_REMOVE_PARM 0x2000000000000000ULL
#define H_BULK_REMOVE_HW 0x3000000000000000ULL
#define H_BULK_REMOVE_RC 0x0c00000000000000ULL
#define H_BULK_REMOVE_FLAGS 0x0300000000000000ULL
#define H_BULK_REMOVE_ABSOLUTE 0x0000000000000000ULL
#define H_BULK_REMOVE_ANDCOND 0x0100000000000000ULL
#define H_BULK_REMOVE_AVPN 0x0200000000000000ULL
#define H_BULK_REMOVE_PTEX 0x00ffffffffffffffULL
#define H_BULK_REMOVE_MAX_BATCH 4
static int kvmppc_h_pr_bulk_remove(struct kvm_vcpu *vcpu)
{
int i;
int paramnr = 4;
int ret = H_SUCCESS;
mutex_lock(&vcpu->kvm->arch.hpt_mutex);
for (i = 0; i < H_BULK_REMOVE_MAX_BATCH; i++) {
unsigned long tsh = kvmppc_get_gpr(vcpu, paramnr+(2*i));
unsigned long tsl = kvmppc_get_gpr(vcpu, paramnr+(2*i)+1);
unsigned long pteg, rb, flags;
unsigned long pte[2];
unsigned long v = 0;
if ((tsh & H_BULK_REMOVE_TYPE) == H_BULK_REMOVE_END) {
break; /* Exit success */
} else if ((tsh & H_BULK_REMOVE_TYPE) !=
H_BULK_REMOVE_REQUEST) {
ret = H_PARAMETER;
break; /* Exit fail */
}
tsh &= H_BULK_REMOVE_PTEX | H_BULK_REMOVE_FLAGS;
tsh |= H_BULK_REMOVE_RESPONSE;
if ((tsh & H_BULK_REMOVE_ANDCOND) &&
(tsh & H_BULK_REMOVE_AVPN)) {
tsh |= H_BULK_REMOVE_PARM;
kvmppc_set_gpr(vcpu, paramnr+(2*i), tsh);
ret = H_PARAMETER;
break; /* Exit fail */
}
pteg = get_pteg_addr(vcpu, tsh & H_BULK_REMOVE_PTEX);
KVM: PPC: Book3S PR: Check copy_to/from_user return values The PR KVM implementation of the PAPR HPT hypercalls (H_ENTER etc.) access an image of the HPT in userspace memory using copy_from_user and copy_to_user. Recently, the declarations of those functions were annotated to indicate that the return value must be checked. Since this code doesn't currently check the return value, this causes compile warnings like the ones shown below, and since on PPC the default is to compile arch/powerpc with -Werror, this causes the build to fail. To fix this, we check the return values, and if non-zero, fail the hypercall being processed with a H_FUNCTION error return value. There is really no good error return value to use since PAPR didn't envisage the possibility that the hypervisor may not be able to access the guest's HPT, and H_FUNCTION (function not supported) seems as good as any. The typical compile warnings look like this: CC arch/powerpc/kvm/book3s_pr_papr.o /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c: In function ‘kvmppc_h_pr_enter’: /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:53:2: error: ignoring return value of ‘copy_from_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg)); ^ /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:74:2: error: ignoring return value of ‘copy_to_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_to_user((void __user *)pteg_addr, hpte, HPTE_SIZE); ^ ... etc. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-05-11 09:33:30 +08:00
if (copy_from_user(pte, (void __user *)pteg, sizeof(pte))) {
ret = H_FUNCTION;
break;
}
pte[0] = be64_to_cpu((__force __be64)pte[0]);
pte[1] = be64_to_cpu((__force __be64)pte[1]);
/* tsl = AVPN */
flags = (tsh & H_BULK_REMOVE_FLAGS) >> 26;
if ((pte[0] & HPTE_V_VALID) == 0 ||
((flags & H_AVPN) && (pte[0] & ~0x7fUL) != tsl) ||
((flags & H_ANDCOND) && (pte[0] & tsl) != 0)) {
tsh |= H_BULK_REMOVE_NOT_FOUND;
} else {
/* Splat the pteg in (userland) hpt */
KVM: PPC: Book3S PR: Check copy_to/from_user return values The PR KVM implementation of the PAPR HPT hypercalls (H_ENTER etc.) access an image of the HPT in userspace memory using copy_from_user and copy_to_user. Recently, the declarations of those functions were annotated to indicate that the return value must be checked. Since this code doesn't currently check the return value, this causes compile warnings like the ones shown below, and since on PPC the default is to compile arch/powerpc with -Werror, this causes the build to fail. To fix this, we check the return values, and if non-zero, fail the hypercall being processed with a H_FUNCTION error return value. There is really no good error return value to use since PAPR didn't envisage the possibility that the hypervisor may not be able to access the guest's HPT, and H_FUNCTION (function not supported) seems as good as any. The typical compile warnings look like this: CC arch/powerpc/kvm/book3s_pr_papr.o /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c: In function ‘kvmppc_h_pr_enter’: /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:53:2: error: ignoring return value of ‘copy_from_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg)); ^ /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:74:2: error: ignoring return value of ‘copy_to_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_to_user((void __user *)pteg_addr, hpte, HPTE_SIZE); ^ ... etc. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-05-11 09:33:30 +08:00
if (copy_to_user((void __user *)pteg, &v, sizeof(v))) {
ret = H_FUNCTION;
break;
}
rb = compute_tlbie_rb(pte[0], pte[1],
tsh & H_BULK_REMOVE_PTEX);
vcpu->arch.mmu.tlbie(vcpu, rb, rb & 1 ? true : false);
tsh |= H_BULK_REMOVE_SUCCESS;
tsh |= (pte[1] & (HPTE_R_C | HPTE_R_R)) << 43;
}
kvmppc_set_gpr(vcpu, paramnr+(2*i), tsh);
}
mutex_unlock(&vcpu->kvm->arch.hpt_mutex);
kvmppc_set_gpr(vcpu, 3, ret);
return EMULATE_DONE;
}
static int kvmppc_h_pr_protect(struct kvm_vcpu *vcpu)
{
unsigned long flags = kvmppc_get_gpr(vcpu, 4);
unsigned long pte_index = kvmppc_get_gpr(vcpu, 5);
unsigned long avpn = kvmppc_get_gpr(vcpu, 6);
unsigned long rb, pteg, r, v;
unsigned long pte[2];
long int ret;
pteg = get_pteg_addr(vcpu, pte_index);
mutex_lock(&vcpu->kvm->arch.hpt_mutex);
KVM: PPC: Book3S PR: Check copy_to/from_user return values The PR KVM implementation of the PAPR HPT hypercalls (H_ENTER etc.) access an image of the HPT in userspace memory using copy_from_user and copy_to_user. Recently, the declarations of those functions were annotated to indicate that the return value must be checked. Since this code doesn't currently check the return value, this causes compile warnings like the ones shown below, and since on PPC the default is to compile arch/powerpc with -Werror, this causes the build to fail. To fix this, we check the return values, and if non-zero, fail the hypercall being processed with a H_FUNCTION error return value. There is really no good error return value to use since PAPR didn't envisage the possibility that the hypervisor may not be able to access the guest's HPT, and H_FUNCTION (function not supported) seems as good as any. The typical compile warnings look like this: CC arch/powerpc/kvm/book3s_pr_papr.o /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c: In function ‘kvmppc_h_pr_enter’: /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:53:2: error: ignoring return value of ‘copy_from_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg)); ^ /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:74:2: error: ignoring return value of ‘copy_to_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_to_user((void __user *)pteg_addr, hpte, HPTE_SIZE); ^ ... etc. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-05-11 09:33:30 +08:00
ret = H_FUNCTION;
if (copy_from_user(pte, (void __user *)pteg, sizeof(pte)))
goto done;
pte[0] = be64_to_cpu((__force __be64)pte[0]);
pte[1] = be64_to_cpu((__force __be64)pte[1]);
ret = H_NOT_FOUND;
if ((pte[0] & HPTE_V_VALID) == 0 ||
((flags & H_AVPN) && (pte[0] & ~0x7fUL) != avpn))
goto done;
v = pte[0];
r = pte[1];
r &= ~(HPTE_R_PP0 | HPTE_R_PP | HPTE_R_N | HPTE_R_KEY_HI |
HPTE_R_KEY_LO);
r |= (flags << 55) & HPTE_R_PP0;
r |= (flags << 48) & HPTE_R_KEY_HI;
r |= flags & (HPTE_R_PP | HPTE_R_N | HPTE_R_KEY_LO);
pte[1] = r;
rb = compute_tlbie_rb(v, r, pte_index);
vcpu->arch.mmu.tlbie(vcpu, rb, rb & 1 ? true : false);
pte[0] = (__force u64)cpu_to_be64(pte[0]);
pte[1] = (__force u64)cpu_to_be64(pte[1]);
KVM: PPC: Book3S PR: Check copy_to/from_user return values The PR KVM implementation of the PAPR HPT hypercalls (H_ENTER etc.) access an image of the HPT in userspace memory using copy_from_user and copy_to_user. Recently, the declarations of those functions were annotated to indicate that the return value must be checked. Since this code doesn't currently check the return value, this causes compile warnings like the ones shown below, and since on PPC the default is to compile arch/powerpc with -Werror, this causes the build to fail. To fix this, we check the return values, and if non-zero, fail the hypercall being processed with a H_FUNCTION error return value. There is really no good error return value to use since PAPR didn't envisage the possibility that the hypervisor may not be able to access the guest's HPT, and H_FUNCTION (function not supported) seems as good as any. The typical compile warnings look like this: CC arch/powerpc/kvm/book3s_pr_papr.o /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c: In function ‘kvmppc_h_pr_enter’: /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:53:2: error: ignoring return value of ‘copy_from_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg)); ^ /home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_pr_papr.c:74:2: error: ignoring return value of ‘copy_to_user’, declared with attribute warn_unused_result [-Werror=unused-result] copy_to_user((void __user *)pteg_addr, hpte, HPTE_SIZE); ^ ... etc. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-05-11 09:33:30 +08:00
ret = H_FUNCTION;
if (copy_to_user((void __user *)pteg, pte, sizeof(pte)))
goto done;
ret = H_SUCCESS;
done:
mutex_unlock(&vcpu->kvm->arch.hpt_mutex);
kvmppc_set_gpr(vcpu, 3, ret);
return EMULATE_DONE;
}
static int kvmppc_h_pr_logical_ci_load(struct kvm_vcpu *vcpu)
{
long rc;
rc = kvmppc_h_logical_ci_load(vcpu);
if (rc == H_TOO_HARD)
return EMULATE_FAIL;
kvmppc_set_gpr(vcpu, 3, rc);
return EMULATE_DONE;
}
static int kvmppc_h_pr_logical_ci_store(struct kvm_vcpu *vcpu)
kvmppc: Implement H_LOGICAL_CI_{LOAD,STORE} in KVM On POWER, storage caching is usually configured via the MMU - attributes such as cache-inhibited are stored in the TLB and the hashed page table. This makes correctly performing cache inhibited IO accesses awkward when the MMU is turned off (real mode). Some CPU models provide special registers to control the cache attributes of real mode load and stores but this is not at all consistent. This is a problem in particular for SLOF, the firmware used on KVM guests, which runs entirely in real mode, but which needs to do IO to load the kernel. To simplify this qemu implements two special hypercalls, H_LOGICAL_CI_LOAD and H_LOGICAL_CI_STORE which simulate a cache-inhibited load or store to a logical address (aka guest physical address). SLOF uses these for IO. However, because these are implemented within qemu, not the host kernel, these bypass any IO devices emulated within KVM itself. The simplest way to see this problem is to attempt to boot a KVM guest from a virtio-blk device with iothread / dataplane enabled. The iothread code relies on an in kernel implementation of the virtio queue notification, which is not triggered by the IO hcalls, and so the guest will stall in SLOF unable to load the guest OS. This patch addresses this by providing in-kernel implementations of the 2 hypercalls, which correctly scan the KVM IO bus. Any access to an address not handled by the KVM IO bus will cause a VM exit, hitting the qemu implementation as before. Note that a userspace change is also required, in order to enable these new hcall implementations with KVM_CAP_PPC_ENABLE_HCALL. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> [agraf: fix compilation] Signed-off-by: Alexander Graf <agraf@suse.de>
2015-02-05 08:53:25 +08:00
{
long rc;
rc = kvmppc_h_logical_ci_store(vcpu);
kvmppc: Implement H_LOGICAL_CI_{LOAD,STORE} in KVM On POWER, storage caching is usually configured via the MMU - attributes such as cache-inhibited are stored in the TLB and the hashed page table. This makes correctly performing cache inhibited IO accesses awkward when the MMU is turned off (real mode). Some CPU models provide special registers to control the cache attributes of real mode load and stores but this is not at all consistent. This is a problem in particular for SLOF, the firmware used on KVM guests, which runs entirely in real mode, but which needs to do IO to load the kernel. To simplify this qemu implements two special hypercalls, H_LOGICAL_CI_LOAD and H_LOGICAL_CI_STORE which simulate a cache-inhibited load or store to a logical address (aka guest physical address). SLOF uses these for IO. However, because these are implemented within qemu, not the host kernel, these bypass any IO devices emulated within KVM itself. The simplest way to see this problem is to attempt to boot a KVM guest from a virtio-blk device with iothread / dataplane enabled. The iothread code relies on an in kernel implementation of the virtio queue notification, which is not triggered by the IO hcalls, and so the guest will stall in SLOF unable to load the guest OS. This patch addresses this by providing in-kernel implementations of the 2 hypercalls, which correctly scan the KVM IO bus. Any access to an address not handled by the KVM IO bus will cause a VM exit, hitting the qemu implementation as before. Note that a userspace change is also required, in order to enable these new hcall implementations with KVM_CAP_PPC_ENABLE_HCALL. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> [agraf: fix compilation] Signed-off-by: Alexander Graf <agraf@suse.de>
2015-02-05 08:53:25 +08:00
if (rc == H_TOO_HARD)
return EMULATE_FAIL;
kvmppc_set_gpr(vcpu, 3, rc);
return EMULATE_DONE;
}
#ifdef CONFIG_SPAPR_TCE_IOMMU
static int kvmppc_h_pr_put_tce(struct kvm_vcpu *vcpu)
kvmppc: Implement H_LOGICAL_CI_{LOAD,STORE} in KVM On POWER, storage caching is usually configured via the MMU - attributes such as cache-inhibited are stored in the TLB and the hashed page table. This makes correctly performing cache inhibited IO accesses awkward when the MMU is turned off (real mode). Some CPU models provide special registers to control the cache attributes of real mode load and stores but this is not at all consistent. This is a problem in particular for SLOF, the firmware used on KVM guests, which runs entirely in real mode, but which needs to do IO to load the kernel. To simplify this qemu implements two special hypercalls, H_LOGICAL_CI_LOAD and H_LOGICAL_CI_STORE which simulate a cache-inhibited load or store to a logical address (aka guest physical address). SLOF uses these for IO. However, because these are implemented within qemu, not the host kernel, these bypass any IO devices emulated within KVM itself. The simplest way to see this problem is to attempt to boot a KVM guest from a virtio-blk device with iothread / dataplane enabled. The iothread code relies on an in kernel implementation of the virtio queue notification, which is not triggered by the IO hcalls, and so the guest will stall in SLOF unable to load the guest OS. This patch addresses this by providing in-kernel implementations of the 2 hypercalls, which correctly scan the KVM IO bus. Any access to an address not handled by the KVM IO bus will cause a VM exit, hitting the qemu implementation as before. Note that a userspace change is also required, in order to enable these new hcall implementations with KVM_CAP_PPC_ENABLE_HCALL. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> [agraf: fix compilation] Signed-off-by: Alexander Graf <agraf@suse.de>
2015-02-05 08:53:25 +08:00
{
unsigned long liobn = kvmppc_get_gpr(vcpu, 4);
unsigned long ioba = kvmppc_get_gpr(vcpu, 5);
unsigned long tce = kvmppc_get_gpr(vcpu, 6);
kvmppc: Implement H_LOGICAL_CI_{LOAD,STORE} in KVM On POWER, storage caching is usually configured via the MMU - attributes such as cache-inhibited are stored in the TLB and the hashed page table. This makes correctly performing cache inhibited IO accesses awkward when the MMU is turned off (real mode). Some CPU models provide special registers to control the cache attributes of real mode load and stores but this is not at all consistent. This is a problem in particular for SLOF, the firmware used on KVM guests, which runs entirely in real mode, but which needs to do IO to load the kernel. To simplify this qemu implements two special hypercalls, H_LOGICAL_CI_LOAD and H_LOGICAL_CI_STORE which simulate a cache-inhibited load or store to a logical address (aka guest physical address). SLOF uses these for IO. However, because these are implemented within qemu, not the host kernel, these bypass any IO devices emulated within KVM itself. The simplest way to see this problem is to attempt to boot a KVM guest from a virtio-blk device with iothread / dataplane enabled. The iothread code relies on an in kernel implementation of the virtio queue notification, which is not triggered by the IO hcalls, and so the guest will stall in SLOF unable to load the guest OS. This patch addresses this by providing in-kernel implementations of the 2 hypercalls, which correctly scan the KVM IO bus. Any access to an address not handled by the KVM IO bus will cause a VM exit, hitting the qemu implementation as before. Note that a userspace change is also required, in order to enable these new hcall implementations with KVM_CAP_PPC_ENABLE_HCALL. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> [agraf: fix compilation] Signed-off-by: Alexander Graf <agraf@suse.de>
2015-02-05 08:53:25 +08:00
long rc;
rc = kvmppc_h_put_tce(vcpu, liobn, ioba, tce);
kvmppc: Implement H_LOGICAL_CI_{LOAD,STORE} in KVM On POWER, storage caching is usually configured via the MMU - attributes such as cache-inhibited are stored in the TLB and the hashed page table. This makes correctly performing cache inhibited IO accesses awkward when the MMU is turned off (real mode). Some CPU models provide special registers to control the cache attributes of real mode load and stores but this is not at all consistent. This is a problem in particular for SLOF, the firmware used on KVM guests, which runs entirely in real mode, but which needs to do IO to load the kernel. To simplify this qemu implements two special hypercalls, H_LOGICAL_CI_LOAD and H_LOGICAL_CI_STORE which simulate a cache-inhibited load or store to a logical address (aka guest physical address). SLOF uses these for IO. However, because these are implemented within qemu, not the host kernel, these bypass any IO devices emulated within KVM itself. The simplest way to see this problem is to attempt to boot a KVM guest from a virtio-blk device with iothread / dataplane enabled. The iothread code relies on an in kernel implementation of the virtio queue notification, which is not triggered by the IO hcalls, and so the guest will stall in SLOF unable to load the guest OS. This patch addresses this by providing in-kernel implementations of the 2 hypercalls, which correctly scan the KVM IO bus. Any access to an address not handled by the KVM IO bus will cause a VM exit, hitting the qemu implementation as before. Note that a userspace change is also required, in order to enable these new hcall implementations with KVM_CAP_PPC_ENABLE_HCALL. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> [agraf: fix compilation] Signed-off-by: Alexander Graf <agraf@suse.de>
2015-02-05 08:53:25 +08:00
if (rc == H_TOO_HARD)
return EMULATE_FAIL;
kvmppc_set_gpr(vcpu, 3, rc);
return EMULATE_DONE;
}
static int kvmppc_h_pr_put_tce_indirect(struct kvm_vcpu *vcpu)
{
unsigned long liobn = kvmppc_get_gpr(vcpu, 4);
unsigned long ioba = kvmppc_get_gpr(vcpu, 5);
unsigned long tce = kvmppc_get_gpr(vcpu, 6);
unsigned long npages = kvmppc_get_gpr(vcpu, 7);
long rc;
rc = kvmppc_h_put_tce_indirect(vcpu, liobn, ioba,
tce, npages);
if (rc == H_TOO_HARD)
return EMULATE_FAIL;
kvmppc_set_gpr(vcpu, 3, rc);
return EMULATE_DONE;
}
static int kvmppc_h_pr_stuff_tce(struct kvm_vcpu *vcpu)
{
unsigned long liobn = kvmppc_get_gpr(vcpu, 4);
unsigned long ioba = kvmppc_get_gpr(vcpu, 5);
unsigned long tce_value = kvmppc_get_gpr(vcpu, 6);
unsigned long npages = kvmppc_get_gpr(vcpu, 7);
long rc;
rc = kvmppc_h_stuff_tce(vcpu, liobn, ioba, tce_value, npages);
if (rc == H_TOO_HARD)
return EMULATE_FAIL;
kvmppc_set_gpr(vcpu, 3, rc);
return EMULATE_DONE;
}
#else /* CONFIG_SPAPR_TCE_IOMMU */
static int kvmppc_h_pr_put_tce(struct kvm_vcpu *vcpu)
{
return EMULATE_FAIL;
}
static int kvmppc_h_pr_put_tce_indirect(struct kvm_vcpu *vcpu)
{
return EMULATE_FAIL;
}
static int kvmppc_h_pr_stuff_tce(struct kvm_vcpu *vcpu)
{
return EMULATE_FAIL;
}
#endif /* CONFIG_SPAPR_TCE_IOMMU */
static int kvmppc_h_pr_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd)
{
long rc = kvmppc_xics_hcall(vcpu, cmd);
kvmppc_set_gpr(vcpu, 3, rc);
return EMULATE_DONE;
}
int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd)
{
int rc, idx;
KVM: PPC: Book3S: Controls for in-kernel sPAPR hypercall handling This provides a way for userspace controls which sPAPR hcalls get handled in the kernel. Each hcall can be individually enabled or disabled for in-kernel handling, except for H_RTAS. The exception for H_RTAS is because userspace can already control whether individual RTAS functions are handled in-kernel or not via the KVM_PPC_RTAS_DEFINE_TOKEN ioctl, and because the numeric value for H_RTAS is out of the normal sequence of hcall numbers. Hcalls are enabled or disabled using the KVM_ENABLE_CAP ioctl for the KVM_CAP_PPC_ENABLE_HCALL capability on the file descriptor for the VM. The args field of the struct kvm_enable_cap specifies the hcall number in args[0] and the enable/disable flag in args[1]; 0 means disable in-kernel handling (so that the hcall will always cause an exit to userspace) and 1 means enable. Enabling or disabling in-kernel handling of an hcall is effective across the whole VM. The ability for KVM_ENABLE_CAP to be used on a VM file descriptor on PowerPC is new, added by this commit. The KVM_CAP_ENABLE_CAP_VM capability advertises that this ability exists. When a VM is created, an initial set of hcalls are enabled for in-kernel handling. The set that is enabled is the set that have an in-kernel implementation at this point. Any new hcall implementations from this point onwards should not be added to the default set without a good reason. No distinction is made between real-mode and virtual-mode hcall implementations; the one setting controls them both. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-06-02 09:02:59 +08:00
if (cmd <= MAX_HCALL_OPCODE &&
!test_bit(cmd/4, vcpu->kvm->arch.enabled_hcalls))
return EMULATE_FAIL;
switch (cmd) {
case H_ENTER:
return kvmppc_h_pr_enter(vcpu);
case H_REMOVE:
return kvmppc_h_pr_remove(vcpu);
case H_PROTECT:
return kvmppc_h_pr_protect(vcpu);
case H_BULK_REMOVE:
return kvmppc_h_pr_bulk_remove(vcpu);
case H_PUT_TCE:
return kvmppc_h_pr_put_tce(vcpu);
case H_PUT_TCE_INDIRECT:
return kvmppc_h_pr_put_tce_indirect(vcpu);
case H_STUFF_TCE:
return kvmppc_h_pr_stuff_tce(vcpu);
case H_CEDE:
kvmppc_set_msr_fast(vcpu, kvmppc_get_msr(vcpu) | MSR_EE);
kvm_vcpu_block(vcpu);
kvm_clear_request(KVM_REQ_UNHALT, vcpu);
vcpu->stat.halt_wakeup++;
return EMULATE_DONE;
kvmppc: Implement H_LOGICAL_CI_{LOAD,STORE} in KVM On POWER, storage caching is usually configured via the MMU - attributes such as cache-inhibited are stored in the TLB and the hashed page table. This makes correctly performing cache inhibited IO accesses awkward when the MMU is turned off (real mode). Some CPU models provide special registers to control the cache attributes of real mode load and stores but this is not at all consistent. This is a problem in particular for SLOF, the firmware used on KVM guests, which runs entirely in real mode, but which needs to do IO to load the kernel. To simplify this qemu implements two special hypercalls, H_LOGICAL_CI_LOAD and H_LOGICAL_CI_STORE which simulate a cache-inhibited load or store to a logical address (aka guest physical address). SLOF uses these for IO. However, because these are implemented within qemu, not the host kernel, these bypass any IO devices emulated within KVM itself. The simplest way to see this problem is to attempt to boot a KVM guest from a virtio-blk device with iothread / dataplane enabled. The iothread code relies on an in kernel implementation of the virtio queue notification, which is not triggered by the IO hcalls, and so the guest will stall in SLOF unable to load the guest OS. This patch addresses this by providing in-kernel implementations of the 2 hypercalls, which correctly scan the KVM IO bus. Any access to an address not handled by the KVM IO bus will cause a VM exit, hitting the qemu implementation as before. Note that a userspace change is also required, in order to enable these new hcall implementations with KVM_CAP_PPC_ENABLE_HCALL. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> [agraf: fix compilation] Signed-off-by: Alexander Graf <agraf@suse.de>
2015-02-05 08:53:25 +08:00
case H_LOGICAL_CI_LOAD:
return kvmppc_h_pr_logical_ci_load(vcpu);
case H_LOGICAL_CI_STORE:
return kvmppc_h_pr_logical_ci_store(vcpu);
case H_XIRR:
case H_CPPR:
case H_EOI:
case H_IPI:
case H_IPOLL:
case H_XIRR_X:
if (kvmppc_xics_enabled(vcpu))
return kvmppc_h_pr_xics_hcall(vcpu, cmd);
break;
case H_RTAS:
if (list_empty(&vcpu->kvm->arch.rtas_tokens))
break;
idx = srcu_read_lock(&vcpu->kvm->srcu);
rc = kvmppc_rtas_hcall(vcpu);
srcu_read_unlock(&vcpu->kvm->srcu, idx);
if (rc)
break;
kvmppc_set_gpr(vcpu, 3, 0);
return EMULATE_DONE;
}
return EMULATE_FAIL;
}
KVM: PPC: Book3S: Controls for in-kernel sPAPR hypercall handling This provides a way for userspace controls which sPAPR hcalls get handled in the kernel. Each hcall can be individually enabled or disabled for in-kernel handling, except for H_RTAS. The exception for H_RTAS is because userspace can already control whether individual RTAS functions are handled in-kernel or not via the KVM_PPC_RTAS_DEFINE_TOKEN ioctl, and because the numeric value for H_RTAS is out of the normal sequence of hcall numbers. Hcalls are enabled or disabled using the KVM_ENABLE_CAP ioctl for the KVM_CAP_PPC_ENABLE_HCALL capability on the file descriptor for the VM. The args field of the struct kvm_enable_cap specifies the hcall number in args[0] and the enable/disable flag in args[1]; 0 means disable in-kernel handling (so that the hcall will always cause an exit to userspace) and 1 means enable. Enabling or disabling in-kernel handling of an hcall is effective across the whole VM. The ability for KVM_ENABLE_CAP to be used on a VM file descriptor on PowerPC is new, added by this commit. The KVM_CAP_ENABLE_CAP_VM capability advertises that this ability exists. When a VM is created, an initial set of hcalls are enabled for in-kernel handling. The set that is enabled is the set that have an in-kernel implementation at this point. Any new hcall implementations from this point onwards should not be added to the default set without a good reason. No distinction is made between real-mode and virtual-mode hcall implementations; the one setting controls them both. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-06-02 09:02:59 +08:00
int kvmppc_hcall_impl_pr(unsigned long cmd)
{
switch (cmd) {
case H_ENTER:
case H_REMOVE:
case H_PROTECT:
case H_BULK_REMOVE:
case H_PUT_TCE:
case H_PUT_TCE_INDIRECT:
case H_STUFF_TCE:
case H_CEDE:
kvmppc: Implement H_LOGICAL_CI_{LOAD,STORE} in KVM On POWER, storage caching is usually configured via the MMU - attributes such as cache-inhibited are stored in the TLB and the hashed page table. This makes correctly performing cache inhibited IO accesses awkward when the MMU is turned off (real mode). Some CPU models provide special registers to control the cache attributes of real mode load and stores but this is not at all consistent. This is a problem in particular for SLOF, the firmware used on KVM guests, which runs entirely in real mode, but which needs to do IO to load the kernel. To simplify this qemu implements two special hypercalls, H_LOGICAL_CI_LOAD and H_LOGICAL_CI_STORE which simulate a cache-inhibited load or store to a logical address (aka guest physical address). SLOF uses these for IO. However, because these are implemented within qemu, not the host kernel, these bypass any IO devices emulated within KVM itself. The simplest way to see this problem is to attempt to boot a KVM guest from a virtio-blk device with iothread / dataplane enabled. The iothread code relies on an in kernel implementation of the virtio queue notification, which is not triggered by the IO hcalls, and so the guest will stall in SLOF unable to load the guest OS. This patch addresses this by providing in-kernel implementations of the 2 hypercalls, which correctly scan the KVM IO bus. Any access to an address not handled by the KVM IO bus will cause a VM exit, hitting the qemu implementation as before. Note that a userspace change is also required, in order to enable these new hcall implementations with KVM_CAP_PPC_ENABLE_HCALL. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> [agraf: fix compilation] Signed-off-by: Alexander Graf <agraf@suse.de>
2015-02-05 08:53:25 +08:00
case H_LOGICAL_CI_LOAD:
case H_LOGICAL_CI_STORE:
#ifdef CONFIG_KVM_XICS
case H_XIRR:
case H_CPPR:
case H_EOI:
case H_IPI:
case H_IPOLL:
case H_XIRR_X:
#endif
return 1;
}
return 0;
}
KVM: PPC: Book3S: Controls for in-kernel sPAPR hypercall handling This provides a way for userspace controls which sPAPR hcalls get handled in the kernel. Each hcall can be individually enabled or disabled for in-kernel handling, except for H_RTAS. The exception for H_RTAS is because userspace can already control whether individual RTAS functions are handled in-kernel or not via the KVM_PPC_RTAS_DEFINE_TOKEN ioctl, and because the numeric value for H_RTAS is out of the normal sequence of hcall numbers. Hcalls are enabled or disabled using the KVM_ENABLE_CAP ioctl for the KVM_CAP_PPC_ENABLE_HCALL capability on the file descriptor for the VM. The args field of the struct kvm_enable_cap specifies the hcall number in args[0] and the enable/disable flag in args[1]; 0 means disable in-kernel handling (so that the hcall will always cause an exit to userspace) and 1 means enable. Enabling or disabling in-kernel handling of an hcall is effective across the whole VM. The ability for KVM_ENABLE_CAP to be used on a VM file descriptor on PowerPC is new, added by this commit. The KVM_CAP_ENABLE_CAP_VM capability advertises that this ability exists. When a VM is created, an initial set of hcalls are enabled for in-kernel handling. The set that is enabled is the set that have an in-kernel implementation at this point. Any new hcall implementations from this point onwards should not be added to the default set without a good reason. No distinction is made between real-mode and virtual-mode hcall implementations; the one setting controls them both. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-06-02 09:02:59 +08:00
/*
* List of hcall numbers to enable by default.
* For compatibility with old userspace, we enable by default
* all hcalls that were implemented before the hcall-enabling
* facility was added. Note this list should not include H_RTAS.
*/
static unsigned int default_hcall_list[] = {
H_ENTER,
H_REMOVE,
H_PROTECT,
H_BULK_REMOVE,
H_PUT_TCE,
H_CEDE,
#ifdef CONFIG_KVM_XICS
H_XIRR,
H_CPPR,
H_EOI,
H_IPI,
H_IPOLL,
H_XIRR_X,
#endif
0
};
void kvmppc_pr_init_default_hcalls(struct kvm *kvm)
{
int i;
unsigned int hcall;
KVM: PPC: Book3S: Controls for in-kernel sPAPR hypercall handling This provides a way for userspace controls which sPAPR hcalls get handled in the kernel. Each hcall can be individually enabled or disabled for in-kernel handling, except for H_RTAS. The exception for H_RTAS is because userspace can already control whether individual RTAS functions are handled in-kernel or not via the KVM_PPC_RTAS_DEFINE_TOKEN ioctl, and because the numeric value for H_RTAS is out of the normal sequence of hcall numbers. Hcalls are enabled or disabled using the KVM_ENABLE_CAP ioctl for the KVM_CAP_PPC_ENABLE_HCALL capability on the file descriptor for the VM. The args field of the struct kvm_enable_cap specifies the hcall number in args[0] and the enable/disable flag in args[1]; 0 means disable in-kernel handling (so that the hcall will always cause an exit to userspace) and 1 means enable. Enabling or disabling in-kernel handling of an hcall is effective across the whole VM. The ability for KVM_ENABLE_CAP to be used on a VM file descriptor on PowerPC is new, added by this commit. The KVM_CAP_ENABLE_CAP_VM capability advertises that this ability exists. When a VM is created, an initial set of hcalls are enabled for in-kernel handling. The set that is enabled is the set that have an in-kernel implementation at this point. Any new hcall implementations from this point onwards should not be added to the default set without a good reason. No distinction is made between real-mode and virtual-mode hcall implementations; the one setting controls them both. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-06-02 09:02:59 +08:00
for (i = 0; default_hcall_list[i]; ++i) {
hcall = default_hcall_list[i];
WARN_ON(!kvmppc_hcall_impl_pr(hcall));
__set_bit(hcall / 4, kvm->arch.enabled_hcalls);
}
KVM: PPC: Book3S: Controls for in-kernel sPAPR hypercall handling This provides a way for userspace controls which sPAPR hcalls get handled in the kernel. Each hcall can be individually enabled or disabled for in-kernel handling, except for H_RTAS. The exception for H_RTAS is because userspace can already control whether individual RTAS functions are handled in-kernel or not via the KVM_PPC_RTAS_DEFINE_TOKEN ioctl, and because the numeric value for H_RTAS is out of the normal sequence of hcall numbers. Hcalls are enabled or disabled using the KVM_ENABLE_CAP ioctl for the KVM_CAP_PPC_ENABLE_HCALL capability on the file descriptor for the VM. The args field of the struct kvm_enable_cap specifies the hcall number in args[0] and the enable/disable flag in args[1]; 0 means disable in-kernel handling (so that the hcall will always cause an exit to userspace) and 1 means enable. Enabling or disabling in-kernel handling of an hcall is effective across the whole VM. The ability for KVM_ENABLE_CAP to be used on a VM file descriptor on PowerPC is new, added by this commit. The KVM_CAP_ENABLE_CAP_VM capability advertises that this ability exists. When a VM is created, an initial set of hcalls are enabled for in-kernel handling. The set that is enabled is the set that have an in-kernel implementation at this point. Any new hcall implementations from this point onwards should not be added to the default set without a good reason. No distinction is made between real-mode and virtual-mode hcall implementations; the one setting controls them both. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-06-02 09:02:59 +08:00
}