@@ -3002,3 +3002,22 @@ Parameters: args[0] is the XICS device fd
args[1] is the XICS CPU number (server ID) for this vcpu
This capability connects the vcpu to an in-kernel XICS device.
+
+6.8 KVM_CAP_PPC_ENABLE_HCALL
+
+Architectures: ppc (VM capability)
+Parameters: args[0] is the PAPR hcall number
+ args[1] is 0 to disable, 1 to enable in-kernel handling
+
+This capability controls whether individual PAPR hypercalls (hcalls)
+get handled by the kernel or not. Enabling or disabling in-kernel
+handling of an hcall is effective across the VM. On creation, an
+initial set of hcalls are enabled for in-kernel handling, which
+consists of those hcalls for which in-kernel handlers were implemented
+before this capability was implemented. If disabled, the kernel will
+not to attempt to handle the hcall, but will always exit to userspace
+to handle it. Note that it may not make sense to enable some and
+disable others of a group of related hcalls, but KVM does not prevent
+userspace from doing that.
+
+This capability is a VM-level capability, not a VCPU capability.
@@ -189,6 +189,7 @@ extern void kvmppc_hv_entry_trampoline(void);
extern u32 kvmppc_alignment_dsisr(struct kvm_vcpu *vcpu, unsigned int inst);
extern ulong kvmppc_alignment_dar(struct kvm_vcpu *vcpu, unsigned int inst);
extern int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd);
+extern void kvmppc_pr_init_default_hcalls(struct kvm *kvm);
extern void kvmppc_copy_to_svcpu(struct kvmppc_book3s_shadow_vcpu *svcpu,
struct kvm_vcpu *vcpu);
extern void kvmppc_copy_from_svcpu(struct kvm_vcpu *vcpu,
@@ -34,6 +34,7 @@
#include <asm/processor.h>
#include <asm/page.h>
#include <asm/cacheflush.h>
+#include <asm/hvcall.h>
#define KVM_MAX_VCPUS NR_CPUS
#define KVM_MAX_VCORES NR_CPUS
@@ -263,6 +264,7 @@ struct kvm_arch {
#ifdef CONFIG_PPC_BOOK3S_64
struct list_head spapr_tce_tables;
struct list_head rtas_tokens;
+ DECLARE_BITMAP(enabled_hcalls, MAX_HCALL_OPCODE/4 + 1);
#endif
#ifdef CONFIG_KVM_MPIC
struct openpic *mpic;
@@ -492,6 +492,7 @@ int main(void)
DEFINE(KVM_HOST_SDR1, offsetof(struct kvm, arch.host_sdr1));
DEFINE(KVM_TLBIE_LOCK, offsetof(struct kvm, arch.tlbie_lock));
DEFINE(KVM_NEED_FLUSH, offsetof(struct kvm, arch.need_tlb_flush.bits));
+ DEFINE(KVM_ENABLED_HCALLS, offsetof(struct kvm, arch.enabled_hcalls));
DEFINE(KVM_LPCR, offsetof(struct kvm, arch.lpcr));
DEFINE(KVM_RMOR, offsetof(struct kvm, arch.rmor));
DEFINE(KVM_VRMA_SLB_V, offsetof(struct kvm, arch.vrma_slb_v));
@@ -67,6 +67,8 @@
/* Used as a "null" value for timebase values */
#define TB_NIL (~(u64)0)
+static DECLARE_BITMAP(default_enabled_hcalls, MAX_HCALL_OPCODE/4 + 1);
+
static void kvmppc_end_cede(struct kvm_vcpu *vcpu);
static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu);
@@ -562,6 +564,10 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
struct kvm_vcpu *tvcpu;
int idx, rc;
+ if (req <= MAX_HCALL_OPCODE &&
+ !test_bit(req/4, vcpu->kvm->arch.enabled_hcalls))
+ return RESUME_HOST;
+
switch (req) {
case H_ENTER:
idx = srcu_read_lock(&vcpu->kvm->srcu);
@@ -2275,6 +2281,10 @@ static int kvmppc_core_init_vm_hv(struct kvm *kvm)
*/
cpumask_setall(&kvm->arch.need_tlb_flush);
+ /* Start out with the default set of hcalls enabled */
+ memcpy(kvm->arch.enabled_hcalls, default_enabled_hcalls,
+ sizeof(kvm->arch.enabled_hcalls));
+
kvm->arch.rma = NULL;
kvm->arch.host_sdr1 = mfspr(SPRN_SDR1);
@@ -2413,6 +2423,45 @@ static long kvm_arch_vm_ioctl_hv(struct file *filp,
return r;
}
+/*
+ * 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_REMOVE,
+ H_ENTER,
+ H_READ,
+ H_PROTECT,
+ H_BULK_REMOVE,
+ H_GET_TCE,
+ H_PUT_TCE,
+ H_SET_DABR,
+ H_SET_XDABR,
+ H_CEDE,
+ H_PROD,
+ H_CONFER,
+ H_REGISTER_VPA,
+#ifdef CONFIG_KVM_XICS
+ H_EOI,
+ H_CPPR,
+ H_IPI,
+ H_IPOLL,
+ H_XIRR,
+ H_XIRR_X,
+#endif
+ 0
+};
+
+static void init_default_hcalls(void)
+{
+ int i;
+
+ for (i = 0; default_hcall_list[i]; ++i)
+ __set_bit(default_hcall_list[i] / 4, default_enabled_hcalls);
+}
+
static struct kvmppc_ops kvm_ops_hv = {
.get_sregs = kvm_arch_vcpu_ioctl_get_sregs_hv,
.set_sregs = kvm_arch_vcpu_ioctl_set_sregs_hv,
@@ -2460,6 +2509,8 @@ static int kvmppc_book3s_init_hv(void)
kvm_ops_hv.owner = THIS_MODULE;
kvmppc_hv_ops = &kvm_ops_hv;
+ init_default_hcalls();
+
r = kvmppc_mmu_hv_init();
return r;
}
@@ -1795,6 +1795,17 @@ hcall_try_real_mode:
clrrdi r3,r3,2
cmpldi r3,hcall_real_table_end - hcall_real_table
bge guest_exit_cont
+ /* See if this hcall is enabled for in-kernel handling */
+ ld r4, VCPU_KVM(r9)
+ srdi r0, r3, 8 /* r0 = (r3 / 4) >> 6 */
+ sldi r0, r0, 3 /* index into kvm->arch.enabled_hcalls[] */
+ add r4, r4, r0
+ ld r0, KVM_ENABLED_HCALLS(r4)
+ rlwinm r4, r3, 32-2, 0x3f /* r4 = (r3 / 4) & 0x3f */
+ srd r0, r0, r4
+ andi. r0, r0, 1
+ beq guest_exit_cont
+ /* Get pointer to handler, if any, and call it */
LOAD_REG_ADDR(r4, hcall_real_table)
lwax r3,r3,r4
cmpwi r3,0
@@ -1568,6 +1568,11 @@ static int kvmppc_core_init_vm_pr(struct kvm *kvm)
{
mutex_init(&kvm->arch.hpt_mutex);
+#ifdef CONFIG_PPC_BOOK3S_64
+ /* Start out with the default set of hcalls enabled */
+ kvmppc_pr_init_default_hcalls(kvm);
+#endif
+
if (firmware_has_feature(FW_FEATURE_SET_MODE)) {
spin_lock(&kvm_global_user_count_lock);
if (++kvm_global_user_count == 1)
@@ -266,6 +266,10 @@ static int kvmppc_h_pr_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd)
int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd)
{
+ 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);
@@ -303,3 +307,36 @@ int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd)
return EMULATE_FAIL;
}
+
+
+/*
+ * 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;
+
+ for (i = 0; default_hcall_list[i]; ++i)
+ __set_bit(default_hcall_list[i] / 4, kvm->arch.enabled_hcalls);
+}
@@ -387,6 +387,7 @@ int kvm_dev_ioctl_check_extension(long ext)
case KVM_CAP_PPC_UNSET_IRQ:
case KVM_CAP_PPC_IRQ_LEVEL:
case KVM_CAP_ENABLE_CAP:
+ case KVM_CAP_ENABLE_CAP_VM:
case KVM_CAP_ONE_REG:
case KVM_CAP_IOEVENTFD:
case KVM_CAP_DEVICE_CTRL:
@@ -417,6 +418,7 @@ int kvm_dev_ioctl_check_extension(long ext)
case KVM_CAP_PPC_ALLOC_HTAB:
case KVM_CAP_PPC_RTAS:
case KVM_CAP_PPC_FIXUP_HCALL:
+ case KVM_CAP_PPC_ENABLE_HCALL:
#ifdef CONFIG_KVM_XICS
case KVM_CAP_IRQ_XICS:
#endif
@@ -1099,6 +1101,40 @@ int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_event,
return 0;
}
+
+static int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
+ struct kvm_enable_cap *cap)
+{
+ int r;
+
+ if (cap->flags)
+ return -EINVAL;
+
+ switch (cap->cap) {
+#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
+ case KVM_CAP_PPC_ENABLE_HCALL: {
+ unsigned long hcall = cap->args[0];
+
+ r = -EINVAL;
+ if (hcall > MAX_HCALL_OPCODE || (hcall & 3) ||
+ cap->args[1] > 1)
+ break;
+ if (cap->args[1])
+ set_bit(hcall / 4, kvm->arch.enabled_hcalls);
+ else
+ clear_bit(hcall / 4, kvm->arch.enabled_hcalls);
+ r = 0;
+ break;
+ }
+#endif
+ default:
+ r = -EINVAL;
+ break;
+ }
+
+ return r;
+}
+
long kvm_arch_vm_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
@@ -1118,6 +1154,15 @@ long kvm_arch_vm_ioctl(struct file *filp,
break;
}
+ case KVM_ENABLE_CAP:
+ {
+ struct kvm_enable_cap cap;
+ r = -EFAULT;
+ if (copy_from_user(&cap, argp, sizeof(cap)))
+ goto out;
+ r = kvm_vm_ioctl_enable_cap(kvm, &cap);
+ break;
+ }
#ifdef CONFIG_PPC_BOOK3S_64
case KVM_CREATE_SPAPR_TCE: {
struct kvm_create_spapr_tce create_tce;
@@ -758,6 +758,7 @@ struct kvm_ppc_smmu_info {
#define KVM_CAP_VM_ATTRIBUTES 101
#define KVM_CAP_ARM_PSCI_0_2 102
#define KVM_CAP_PPC_FIXUP_HCALL 103
+#define KVM_CAP_PPC_ENABLE_HCALL 104
#ifdef KVM_CAP_IRQ_ROUTING
This provides a way for userspace controls which PAPR 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> --- Documentation/virtual/kvm/api.txt | 19 ++++++++++++ arch/powerpc/include/asm/kvm_book3s.h | 1 + arch/powerpc/include/asm/kvm_host.h | 2 ++ arch/powerpc/kernel/asm-offsets.c | 1 + arch/powerpc/kvm/book3s_hv.c | 51 +++++++++++++++++++++++++++++++++ arch/powerpc/kvm/book3s_hv_rmhandlers.S | 11 +++++++ arch/powerpc/kvm/book3s_pr.c | 5 ++++ arch/powerpc/kvm/book3s_pr_papr.c | 37 ++++++++++++++++++++++++ arch/powerpc/kvm/powerpc.c | 45 +++++++++++++++++++++++++++++ include/uapi/linux/kvm.h | 1 + 10 files changed, 173 insertions(+)