eax, ebx, ecx, edx: the values returned by the cpuid instruction for
this function/index combination
+4.89 KVM_S390_MEM_OP
+
+Capability: KVM_CAP_S390_MEM_OP
+Architectures: s390
+Type: vcpu ioctl
+Parameters: struct kvm_s390_mem_op (in)
+Returns: = 0 on success,
+ < 0 on generic error (e.g. -EFAULT or -ENOMEM),
+ > 0 if an exception occurred while walking the page tables
+
+Read or write data from/to the logical (virtual) memory of a VPCU.
+
+Parameters are specified via the following structure:
+
+struct kvm_s390_mem_op {
+ __u64 gaddr; /* the guest address */
+ __u64 flags; /* flags */
+ __u32 size; /* amount of bytes */
+ __u32 op; /* type of operation */
+ __u64 buf; /* buffer in userspace */
+ __u8 ar; /* the access register number */
+ __u8 reserved[31]; /* should be set to 0 */
+};
+
+The type of operation is specified in the "op" field. It is either
+KVM_S390_MEMOP_LOGICAL_READ for reading from logical memory space or
+KVM_S390_MEMOP_LOGICAL_WRITE for writing to logical memory space. The
+KVM_S390_MEMOP_F_CHECK_ONLY flag can be set in the "flags" field to check
+whether the corresponding memory access would create an access exception
+(without touching the data in the memory at the destination). In case an
+access exception occurred while walking the MMU tables of the guest, the
+ioctl returns a positive error number to indicate the type of exception.
+This exception is also raised directly at the corresponding VCPU if the
+flag KVM_S390_MEMOP_F_INJECT_EXCEPTION is set in the "flags" field.
+
+The start address of the memory region has to be specified in the "gaddr"
+field, and the length of the region in the "size" field. "buf" is the buffer
+supplied by the userspace application where the read data should be written
+to for KVM_S390_MEMOP_LOGICAL_READ, or where the data that should be written
+is stored for a KVM_S390_MEMOP_LOGICAL_WRITE. "buf" is unused and can be NULL
+when KVM_S390_MEMOP_F_CHECK_ONLY is specified. "ar" designates the access
+register number to be used.
+
+The "reserved" field is meant for future extensions. It is not used by
+KVM with the currently defined set of flags.
+
5. The kvm_run structure
------------------------
return rc;
}
+/**
+ * check_gva_range - test a range of guest virtual addresses for accessibility
+ */
+int check_gva_range(struct kvm_vcpu *vcpu, unsigned long gva, ar_t ar,
+ unsigned long length, int is_write)
+{
+ unsigned long gpa;
+ unsigned long currlen;
+ int rc = 0;
+
+ ipte_lock(vcpu);
+ while (length > 0 && !rc) {
+ currlen = min(length, PAGE_SIZE - (gva % PAGE_SIZE));
+ rc = guest_translate_address(vcpu, gva, ar, &gpa, is_write);
+ gva += currlen;
+ length -= currlen;
+ }
+ ipte_unlock(vcpu);
+
+ return rc;
+}
+
/**
* kvm_s390_check_low_addr_prot_real - check for low-address protection
* @gra: Guest real address
int guest_translate_address(struct kvm_vcpu *vcpu, unsigned long gva,
ar_t ar, unsigned long *gpa, int write);
+int check_gva_range(struct kvm_vcpu *vcpu, unsigned long gva, ar_t ar,
+ unsigned long length, int is_write);
int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, ar_t ar, void *data,
unsigned long len, int write);
#include <linux/random.h>
#include <linux/slab.h>
#include <linux/timer.h>
+#include <linux/vmalloc.h>
#include <asm/asm-offsets.h>
#include <asm/lowcore.h>
#include <asm/pgtable.h>
#include "trace.h"
#include "trace-s390.h"
+#define MEM_OP_MAX_SIZE 65536 /* Maximum transfer size for KVM_S390_MEM_OP */
+
#define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU
struct kvm_stats_debugfs_item debugfs_entries[] = {
case KVM_CAP_S390_USER_SIGP:
r = 1;
break;
+ case KVM_CAP_S390_MEM_OP:
+ r = MEM_OP_MAX_SIZE;
+ break;
case KVM_CAP_NR_VCPUS:
case KVM_CAP_MAX_VCPUS:
r = KVM_MAX_VCPUS;
return r;
}
+static long kvm_s390_guest_mem_op(struct kvm_vcpu *vcpu,
+ struct kvm_s390_mem_op *mop)
+{
+ void __user *uaddr = (void __user *)mop->buf;
+ void *tmpbuf = NULL;
+ int r, srcu_idx;
+ const u64 supported_flags = KVM_S390_MEMOP_F_INJECT_EXCEPTION
+ | KVM_S390_MEMOP_F_CHECK_ONLY;
+
+ if (mop->flags & ~supported_flags)
+ return -EINVAL;
+
+ if (mop->size > MEM_OP_MAX_SIZE)
+ return -E2BIG;
+
+ if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) {
+ tmpbuf = vmalloc(mop->size);
+ if (!tmpbuf)
+ return -ENOMEM;
+ }
+
+ srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
+
+ switch (mop->op) {
+ case KVM_S390_MEMOP_LOGICAL_READ:
+ if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) {
+ r = check_gva_range(vcpu, mop->gaddr, mop->ar, mop->size, false);
+ break;
+ }
+ r = read_guest(vcpu, mop->gaddr, mop->ar, tmpbuf, mop->size);
+ if (r == 0) {
+ if (copy_to_user(uaddr, tmpbuf, mop->size))
+ r = -EFAULT;
+ }
+ break;
+ case KVM_S390_MEMOP_LOGICAL_WRITE:
+ if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) {
+ r = check_gva_range(vcpu, mop->gaddr, mop->ar, mop->size, true);
+ break;
+ }
+ if (copy_from_user(tmpbuf, uaddr, mop->size)) {
+ r = -EFAULT;
+ break;
+ }
+ r = write_guest(vcpu, mop->gaddr, mop->ar, tmpbuf, mop->size);
+ break;
+ default:
+ r = -EINVAL;
+ }
+
+ srcu_read_unlock(&vcpu->kvm->srcu, srcu_idx);
+
+ if (r > 0 && (mop->flags & KVM_S390_MEMOP_F_INJECT_EXCEPTION) != 0)
+ kvm_s390_inject_prog_irq(vcpu, &vcpu->arch.pgm);
+
+ vfree(tmpbuf);
+ return r;
+}
+
long kvm_arch_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
break;
}
+ case KVM_S390_MEM_OP: {
+ struct kvm_s390_mem_op mem_op;
+
+ if (copy_from_user(&mem_op, argp, sizeof(mem_op)) == 0)
+ r = kvm_s390_guest_mem_op(vcpu, &mem_op);
+ else
+ r = -EFAULT;
+ break;
+ }
default:
r = -ENOTTY;
}
__u8 pad[5];
};
+/* for KVM_S390_MEM_OP */
+struct kvm_s390_mem_op {
+ /* in */
+ __u64 gaddr; /* the guest address */
+ __u64 flags; /* flags */
+ __u32 size; /* amount of bytes */
+ __u32 op; /* type of operation */
+ __u64 buf; /* buffer in userspace */
+ __u8 ar; /* the access register number */
+ __u8 reserved[31]; /* 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
+/* 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)
+
/* for KVM_INTERRUPT */
struct kvm_interrupt {
/* in */
#define KVM_CAP_CHECK_EXTENSION_VM 105
#define KVM_CAP_S390_USER_SIGP 106
#define KVM_CAP_S390_VECTOR_REGISTERS 107
+#define KVM_CAP_S390_MEM_OP 108
#ifdef KVM_CAP_IRQ_ROUTING
#define KVM_ARM_VCPU_INIT _IOW(KVMIO, 0xae, struct kvm_vcpu_init)
#define KVM_ARM_PREFERRED_TARGET _IOR(KVMIO, 0xaf, struct kvm_vcpu_init)
#define KVM_GET_REG_LIST _IOWR(KVMIO, 0xb0, struct kvm_reg_list)
+/* Available with KVM_CAP_S390_MEM_OP */
+#define KVM_S390_MEM_OP _IOW(KVMIO, 0xb1, struct kvm_s390_mem_op)
#define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0)
#define KVM_DEV_ASSIGN_PCI_2_3 (1 << 1)
projects / users / jedix / linux-maple.git / commitdiff