From: Christian Borntraeger <borntraeger@de.ibm.com>
To: Christian Borntraeger <borntraeger@de.ibm.com>,
Janosch Frank <frankja@linux.vnet.ibm.com>
Cc: KVM <kvm@vger.kernel.org>, Cornelia Huck <cohuck@redhat.com>,
David Hildenbrand <david@redhat.com>,
Thomas Huth <thuth@redhat.com>,
Ulrich Weigand <Ulrich.Weigand@de.ibm.com>,
Claudio Imbrenda <imbrenda@linux.ibm.com>,
Andrea Arcangeli <aarcange@redhat.com>
Subject: [RFCv2 21/37] KVM: S390: protvirt: Introduce instruction data area bounce buffer
Date: Mon, 3 Feb 2020 08:19:41 -0500 [thread overview]
Message-ID: <20200203131957.383915-22-borntraeger@de.ibm.com> (raw)
In-Reply-To: <20200203131957.383915-1-borntraeger@de.ibm.com>
From: Janosch Frank <frankja@linux.ibm.com>
Now that we can't access guest memory anymore, we have a dedicated
sattelite block that's a bounce buffer for instruction data.
We re-use the memop interface to copy the instruction data to / from
userspace. This lets us re-use a lot of QEMU code which used that
interface to make logical guest memory accesses which are not possible
anymore in protected mode anyway.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
arch/s390/include/asm/kvm_host.h | 11 ++++++-
arch/s390/kvm/kvm-s390.c | 49 ++++++++++++++++++++++++++++++++
arch/s390/kvm/pv.c | 9 ++++++
include/uapi/linux/kvm.h | 11 +++++--
4 files changed, 77 insertions(+), 3 deletions(-)
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 125511ec6eb0..48f382680755 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -127,6 +127,12 @@ struct mcck_volatile_info {
#define CR14_INITIAL_MASK (CR14_UNUSED_32 | CR14_UNUSED_33 | \
CR14_EXTERNAL_DAMAGE_SUBMASK)
+#define SIDAD_SIZE_MASK 0xff
+#define sida_origin(sie_block) \
+ (sie_block->sidad & PAGE_MASK)
+#define sida_size(sie_block) \
+ (((sie_block->sidad & SIDAD_SIZE_MASK) + 1) * PAGE_SIZE)
+
#define CPUSTAT_STOPPED 0x80000000
#define CPUSTAT_WAIT 0x10000000
#define CPUSTAT_ECALL_PEND 0x08000000
@@ -315,7 +321,10 @@ struct kvm_s390_sie_block {
#define CRYCB_FORMAT2 0x00000003
__u32 crycbd; /* 0x00fc */
__u64 gcr[16]; /* 0x0100 */
- __u64 gbea; /* 0x0180 */
+ union {
+ __u64 gbea; /* 0x0180 */
+ __u64 sidad;
+ };
__u8 reserved188[8]; /* 0x0188 */
__u64 sdnxo; /* 0x0190 */
__u8 reserved198[8]; /* 0x0198 */
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 1945180b857a..76303b0f1226 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -4441,6 +4441,8 @@ static long kvm_s390_guest_mem_op(struct kvm_vcpu *vcpu,
const u64 supported_flags = KVM_S390_MEMOP_F_INJECT_EXCEPTION
| KVM_S390_MEMOP_F_CHECK_ONLY;
+
+ BUILD_BUG_ON(sizeof(*mop) != 64);
if (mop->flags & ~supported_flags || mop->ar >= NUM_ACRS || !mop->size)
return -EINVAL;
@@ -4522,6 +4524,39 @@ long kvm_arch_vcpu_async_ioctl(struct file *filp,
}
#ifdef CONFIG_KVM_S390_PROTECTED_VIRTUALIZATION_HOST
+static long kvm_s390_guest_sida_op(struct kvm_vcpu *vcpu,
+ struct kvm_s390_mem_op *mop)
+{
+ int r = 0;
+ void __user *uaddr = (void __user *)mop->buf;
+
+ if (mop->flags || !mop->size)
+ return -EINVAL;
+
+ if (mop->size > sida_size(vcpu->arch.sie_block))
+ return -E2BIG;
+
+ if (mop->size + mop->offset > sida_size(vcpu->arch.sie_block))
+ return -E2BIG;
+
+ switch (mop->op) {
+ case KVM_S390_MEMOP_SIDA_READ:
+ r = 0;
+ if (copy_to_user(uaddr, (void *)sida_origin(vcpu->arch.sie_block) +
+ mop->offset, mop->size))
+ r = -EFAULT;
+
+ break;
+ case KVM_S390_MEMOP_SIDA_WRITE:
+ r = 0;
+ if (copy_from_user((void *)vcpu->arch.sie_block->sidad +
+ mop->offset, uaddr, mop->size))
+ r = -EFAULT;
+ break;
+ }
+ return r;
+}
+
static int kvm_s390_handle_pv_vcpu(struct kvm_vcpu *vcpu,
struct kvm_pv_cmd *cmd)
{
@@ -4708,6 +4743,20 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
r = kvm_s390_handle_pv_vcpu(vcpu, &args);
break;
}
+ case KVM_S390_SIDA_OP: {
+ struct kvm_s390_mem_op mem_op;
+
+ if (!kvm_s390_pv_is_protected(vcpu->kvm)) {
+ r = -EINVAL;
+ break;
+ }
+
+ if (copy_from_user(&mem_op, argp, sizeof(mem_op)) == 0)
+ r = kvm_s390_guest_sida_op(vcpu, &mem_op);
+ else
+ r = -EFAULT;
+ break;
+ }
#endif
default:
r = -ENOTTY;
diff --git a/arch/s390/kvm/pv.c b/arch/s390/kvm/pv.c
index 24d802072ac7..50e1dc68d972 100644
--- a/arch/s390/kvm/pv.c
+++ b/arch/s390/kvm/pv.c
@@ -93,6 +93,7 @@ int kvm_s390_pv_destroy_cpu(struct kvm_vcpu *vcpu)
free_pages(vcpu->arch.pv.stor_base,
get_order(uv_info.guest_cpu_stor_len));
+ free_page(sida_origin(vcpu->arch.sie_block));
/* Clear cpu and vm handle */
memset(&vcpu->arch.sie_block->reserved10, 0,
sizeof(vcpu->arch.sie_block->reserved10));
@@ -124,6 +125,14 @@ int kvm_s390_pv_create_cpu(struct kvm_vcpu *vcpu)
uvcb.state_origin = (u64)vcpu->arch.sie_block;
uvcb.stor_origin = (u64)vcpu->arch.pv.stor_base;
+ /* Alloc Secure Instruction Data Area Designation */
+ vcpu->arch.sie_block->sidad = __get_free_page(GFP_KERNEL | __GFP_ZERO);
+ if (!vcpu->arch.sie_block->sidad) {
+ free_pages(vcpu->arch.pv.stor_base,
+ get_order(uv_info.guest_cpu_stor_len));
+ return -ENOMEM;
+ }
+
rc = uv_call(0, (u64)&uvcb);
VCPU_EVENT(vcpu, 3, "PROTVIRT CREATE VCPU: cpu %d handle %llx rc %x rrc %x",
vcpu->vcpu_id, uvcb.cpu_handle, uvcb.header.rc,
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index eab741bc12c3..20969ce12096 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -466,7 +466,7 @@ struct kvm_translation {
__u8 pad[5];
};
-/* for KVM_S390_MEM_OP */
+/* for KVM_S390_MEM_OP and KVM_S390_SIDA_OP */
struct kvm_s390_mem_op {
/* in */
__u64 gaddr; /* the guest address */
@@ -475,11 +475,17 @@ struct kvm_s390_mem_op {
__u32 op; /* type of operation */
__u64 buf; /* buffer in userspace */
__u8 ar; /* the access register number */
- __u8 reserved[31]; /* should be set to 0 */
+ __u8 reserved21[3]; /* should be set to 0 */
+ __u32 offset; /* offset into the sida */
+ __u8 reserved28[24]; /* should be set to 0 */
};
+
+
/* types for kvm_s390_mem_op->op */
#define KVM_S390_MEMOP_LOGICAL_READ 0
#define KVM_S390_MEMOP_LOGICAL_WRITE 1
+#define KVM_S390_MEMOP_SIDA_READ 2
+#define KVM_S390_MEMOP_SIDA_WRITE 3
/* flags for kvm_s390_mem_op->flags */
#define KVM_S390_MEMOP_F_CHECK_ONLY (1ULL << 0)
#define KVM_S390_MEMOP_F_INJECT_EXCEPTION (1ULL << 1)
@@ -1510,6 +1516,7 @@ struct kvm_pv_cmd {
/* Available with KVM_CAP_S390_PROTECTED */
#define KVM_S390_PV_COMMAND _IOW(KVMIO, 0xc5, struct kvm_pv_cmd)
#define KVM_S390_PV_COMMAND_VCPU _IOW(KVMIO, 0xc6, struct kvm_pv_cmd)
+#define KVM_S390_SIDA_OP _IOW(KVMIO, 0xc7, struct kvm_s390_mem_op)
/* Secure Encrypted Virtualization command */
enum sev_cmd_id {
--
2.24.0
next prev parent reply other threads:[~2020-02-03 13:20 UTC|newest]
Thread overview: 200+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-03 13:19 [RFCv2 00/37] KVM: s390: Add support for protected VMs Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 01/37] DOCUMENTATION: protvirt: Protected virtual machine introduction Christian Borntraeger
2020-02-03 15:42 ` Cornelia Huck
2020-02-03 21:41 ` Christian Borntraeger
2020-02-04 9:19 ` Cornelia Huck
2020-02-04 9:32 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 02/37] s390/protvirt: introduce host side setup Christian Borntraeger
2020-02-03 17:12 ` Cornelia Huck
2020-02-03 22:03 ` Christian Borntraeger
2020-02-04 9:28 ` Cornelia Huck
2020-02-04 9:38 ` Christian Borntraeger
2020-02-04 9:49 ` Cornelia Huck
2020-02-04 8:40 ` Thomas Huth
2020-02-04 9:12 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 03/37] s390/protvirt: add ultravisor initialization Christian Borntraeger
2020-02-04 10:03 ` Thomas Huth
2020-02-04 10:23 ` Cornelia Huck
2020-02-04 11:22 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 04/37] mm:gup/writeback: add callbacks for inaccessible pages Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 05/37] s390/mm: provide memory management functions for protected KVM guests Christian Borntraeger
2020-02-04 10:57 ` Cornelia Huck
2020-02-04 11:48 ` Claudio Imbrenda
2020-02-04 11:56 ` Christian Borntraeger
2020-02-04 12:15 ` Cornelia Huck
2020-02-05 9:52 ` Janosch Frank
2020-02-03 13:19 ` [RFCv2 06/37] s390: add (non)secure page access exceptions handlers Christian Borntraeger
2020-02-04 10:37 ` Thomas Huth
2020-02-04 11:41 ` Claudio Imbrenda
2020-02-04 12:48 ` Thomas Huth
2020-02-04 13:08 ` Claudio Imbrenda
2020-02-04 13:22 ` Thomas Huth
2020-02-04 12:03 ` Christian Borntraeger
2020-02-04 11:18 ` Cornelia Huck
2020-02-04 12:04 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 07/37] KVM: s390: add new variants of UV CALL Christian Borntraeger
2020-02-04 12:11 ` Cornelia Huck
2020-02-04 12:30 ` Claudio Imbrenda
2020-02-04 12:34 ` Cornelia Huck
2020-02-04 13:33 ` Christian Borntraeger
2020-02-04 13:27 ` Thomas Huth
2020-02-04 13:55 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 08/37] KVM: s390: protvirt: Add initial lifecycle handling Christian Borntraeger
2020-02-04 12:13 ` David Hildenbrand
2020-02-04 12:34 ` Christian Borntraeger
2020-02-05 10:01 ` Janosch Frank
2020-02-04 16:27 ` Cornelia Huck
2020-02-04 21:13 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 09/37] KVM: s390: protvirt: Add KVM api documentation Christian Borntraeger
2020-02-04 20:19 ` Thomas Huth
2020-02-04 21:40 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 10/37] KVM: s390: protvirt: Secure memory is not mergeable Christian Borntraeger
2020-02-04 12:15 ` David Hildenbrand
2020-02-04 12:53 ` Christian Borntraeger
2020-02-04 12:54 ` David Hildenbrand
2020-02-04 13:04 ` [PATCH v2 " Christian Borntraeger
2020-02-04 13:05 ` David Hildenbrand
2020-02-03 13:19 ` [RFCv2 11/37] KVM: s390/mm: Make pages accessible before destroying the guest Christian Borntraeger
2020-02-04 20:52 ` Thomas Huth
2020-02-05 9:03 ` Christian Borntraeger
2020-02-05 10:35 ` Cornelia Huck
2020-02-05 18:29 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 12/37] KVM: s390: protvirt: Handle SE notification interceptions Christian Borntraeger
2020-02-04 12:16 ` David Hildenbrand
2020-02-04 12:23 ` Christian Borntraeger
2020-02-04 21:16 ` Thomas Huth
2020-02-04 21:46 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 13/37] KVM: s390: protvirt: Instruction emulation Christian Borntraeger
2020-02-04 12:20 ` David Hildenbrand
2020-02-04 12:29 ` Christian Borntraeger
2020-02-04 17:07 ` Cornelia Huck
2020-02-04 21:21 ` Thomas Huth
2020-02-03 13:19 ` [RFCv2 14/37] KVM: s390: protvirt: Add interruption injection controls Christian Borntraeger
2020-02-05 6:59 ` Thomas Huth
2020-02-05 8:46 ` Christian Borntraeger
2020-02-05 8:56 ` Michael Mueller
2020-02-05 8:54 ` Michael Mueller
2020-02-05 10:45 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 15/37] KVM: s390: protvirt: Implement interruption injection Christian Borntraeger
2020-02-05 9:51 ` Thomas Huth
2020-02-05 10:48 ` Christian Borntraeger
2020-02-05 11:25 ` Cornelia Huck
2020-02-05 17:49 ` Christian Borntraeger
2020-02-06 8:21 ` Cornelia Huck
2020-02-05 17:56 ` Christian Borntraeger
2020-02-05 11:31 ` Cornelia Huck
2020-02-05 11:46 ` Michael Mueller
2020-02-05 12:11 ` Cornelia Huck
2020-02-05 12:26 ` Michael Mueller
2020-02-05 18:00 ` Christian Borntraeger
2020-02-06 8:23 ` Cornelia Huck
2020-02-05 15:30 ` Michael Mueller
2020-02-03 13:19 ` [RFCv2 16/37] KVM: s390: protvirt: Add SCLP interrupt handling Christian Borntraeger
2020-02-05 12:22 ` Cornelia Huck
2020-02-05 18:14 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 17/37] KVM: s390: protvirt: Add machine-check interruption injection controls Christian Borntraeger
2020-02-05 7:06 ` Thomas Huth
2020-02-03 13:19 ` [RFCv2 18/37] KVM: s390: protvirt: Implement machine-check interruption injection Christian Borntraeger
2020-02-05 7:10 ` Thomas Huth
2020-02-05 13:47 ` Cornelia Huck
2020-02-05 18:18 ` Christian Borntraeger
2020-02-06 8:25 ` Cornelia Huck
2020-02-06 9:01 ` Christian Borntraeger
2020-02-06 9:11 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 19/37] KVM: s390: protvirt: Handle spec exception loops Christian Borntraeger
2020-02-05 13:50 ` Cornelia Huck
2020-02-05 18:21 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 20/37] KVM: s390: protvirt: Add new gprs location handling Christian Borntraeger
2020-02-05 11:18 ` Thomas Huth
2020-02-05 18:45 ` Christian Borntraeger
2020-02-05 13:52 ` Cornelia Huck
2020-02-03 13:19 ` Christian Borntraeger [this message]
2020-02-05 11:43 ` [RFCv2 21/37] KVM: S390: protvirt: Introduce instruction data area bounce buffer David Hildenbrand
2020-02-06 8:43 ` Christian Borntraeger
2020-02-05 12:02 ` Thomas Huth
2020-02-05 12:16 ` Janosch Frank
2020-02-05 17:00 ` Thomas Huth
2020-02-06 9:07 ` Christian Borntraeger
2020-02-06 9:18 ` Thomas Huth
2020-02-06 9:21 ` Christian Borntraeger
2020-02-06 9:20 ` Christian Borntraeger
2020-02-06 9:32 ` Janosch Frank
2020-02-06 9:29 ` David Hildenbrand
2020-02-06 9:39 ` [RFCv2.1] " Christian Borntraeger
2020-02-06 9:54 ` David Hildenbrand
2020-02-06 10:02 ` Christian Borntraeger
2020-02-06 10:08 ` David Hildenbrand
2020-02-06 10:10 ` Christian Borntraeger
2020-02-06 12:46 ` Christian Borntraeger
2020-02-06 10:32 ` Thomas Huth
2020-02-06 11:07 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 22/37] KVM: s390: protvirt: handle secure guest prefix pages Christian Borntraeger
2020-02-05 11:51 ` David Hildenbrand
2020-02-05 19:38 ` Christian Borntraeger
2020-02-05 11:52 ` David Hildenbrand
2020-02-05 19:39 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 23/37] KVM: s390/mm: handle guest unpin events Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 24/37] KVM: s390: protvirt: Write sthyi data to instruction data area Christian Borntraeger
2020-02-05 12:09 ` Thomas Huth
2020-02-05 18:52 ` Christian Borntraeger
2020-02-05 14:27 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 25/37] KVM: s390: protvirt: STSI handling Christian Borntraeger
2020-02-05 12:13 ` Thomas Huth
2020-02-05 19:22 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 26/37] KVM: s390: protvirt: disallow one_reg Christian Borntraeger
2020-02-05 12:16 ` Thomas Huth
2020-02-05 19:25 ` Christian Borntraeger
2020-02-05 14:42 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 27/37] KVM: s390: protvirt: Only sync fmt4 registers Christian Borntraeger
2020-02-04 17:15 ` Cornelia Huck
2020-02-04 22:08 ` Christian Borntraeger
2020-02-05 16:29 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 28/37] KVM: s390: protvirt: Add program exception injection Christian Borntraeger
2020-02-05 16:38 ` Cornelia Huck
2020-02-05 19:31 ` Christian Borntraeger
2020-02-05 17:59 ` Thomas Huth
2020-02-05 19:32 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 29/37] DOCUMENTATION: protvirt: Diag 308 IPL Christian Borntraeger
2020-02-03 16:13 ` Cornelia Huck
2020-02-04 8:13 ` Christian Borntraeger
2020-02-04 9:35 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 30/37] KVM: s390: protvirt: Add diag 308 subcode 8 - 10 handling Christian Borntraeger
2020-02-04 18:51 ` Cornelia Huck
2020-02-04 22:19 ` Christian Borntraeger
2020-02-05 18:21 ` Thomas Huth
2020-02-06 10:59 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 31/37] KVM: s390: protvirt: UV calls diag308 0, 1 Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 32/37] KVM: s390: protvirt: Report CPU state to Ultravisor Christian Borntraeger
2020-02-06 11:12 ` Thomas Huth
2020-02-06 11:17 ` Christian Borntraeger
2020-02-06 14:29 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 33/37] KVM: s390: protvirt: Support cmd 5 operation state Christian Borntraeger
2020-02-06 11:21 ` Thomas Huth
2020-02-06 15:17 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 34/37] KVM: s390: protvirt: Add UV debug trace Christian Borntraeger
2020-02-06 9:41 ` Cornelia Huck
2020-02-07 8:05 ` Christian Borntraeger
2020-02-07 8:27 ` Cornelia Huck
2020-02-14 8:32 ` Christian Borntraeger
2020-02-14 8:53 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 35/37] KVM: s390: protvirt: Mask PSW interrupt bits for interception 104 and 112 Christian Borntraeger
2020-02-06 10:10 ` Cornelia Huck
2020-02-06 11:11 ` Christian Borntraeger
2020-02-06 12:03 ` Thomas Huth
2020-02-03 13:19 ` [RFCv2 36/37] KVM: s390: protvirt: do not inject interrupts after start Christian Borntraeger
2020-02-06 10:13 ` Cornelia Huck
2020-02-06 14:24 ` Christian Borntraeger
2020-02-06 12:03 ` Thomas Huth
2020-02-03 13:19 ` [RFCv2 37/37] KVM: s390: protvirt: Add UV cpu reset calls Christian Borntraeger
2020-02-05 18:27 ` Thomas Huth
2020-02-05 20:24 ` Christian Borntraeger
2020-02-06 10:45 ` Cornelia Huck
2020-02-06 14:27 ` Christian Borntraeger
2020-02-06 14:39 ` David Hildenbrand
2020-02-06 15:07 ` Thomas Huth
2020-02-03 13:23 ` [RFCv2 00/37] KVM: s390: Add support for protected VMs Cornelia Huck
2020-02-03 13:32 ` Christian Borntraeger
2020-02-03 14:42 ` Cornelia Huck
2020-02-05 11:34 ` David Hildenbrand
2020-02-05 11:38 ` Christian Borntraeger
2020-02-05 11:40 ` Cornelia Huck
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