Mailing List Archive

[PATCH v3 09/13] viridian: add ExProcessorMasks variant of the IPI hypercall
From: Paul Durrant <pdurrant@amazon.com>

A previous patch introduced variants of the flush hypercalls that take a
'Virtual Processor Set' as an argument rather than a simple 64-bit mask.
This patch introduces a similar variant of the HVCALL_SEND_IPI hypercall
(HVCALL_SEND_IPI_EX).

NOTE: As with HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE/LIST_EX, a guest should
not yet issue the HVCALL_SEND_IPI_EX hypercall as support for
'ExProcessorMasks' is not yet advertised via CPUID.

Signed-off-by: Paul Durrant <pdurrant@amazon.com>
---
Cc: Wei Liu <wl@xen.org>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>

v3:
- Adjust prototype of new function

v2:
- Sanity check size before hvm_copy_from_guest_phys()
---
xen/arch/x86/hvm/viridian/viridian.c | 74 ++++++++++++++++++++++++++++
1 file changed, 74 insertions(+)

diff --git a/xen/arch/x86/hvm/viridian/viridian.c b/xen/arch/x86/hvm/viridian/viridian.c
index 5d0b49012360..93865be5797a 100644
--- a/xen/arch/x86/hvm/viridian/viridian.c
+++ b/xen/arch/x86/hvm/viridian/viridian.c
@@ -860,6 +860,75 @@ static int hvcall_ipi(const union hypercall_input *input,
return 0;
}

+static int hvcall_ipi_ex(const union hypercall_input *input,
+ union hypercall_output *output,
+ paddr_t input_params_gpa,
+ paddr_t output_params_gpa)
+{
+ struct hypercall_vpmask *vpmask = &this_cpu(hypercall_vpmask);
+ struct {
+ uint32_t vector;
+ uint8_t target_vtl;
+ uint8_t reserved_zero[3];
+ struct hv_vpset set;
+ } input_params;
+ union hypercall_vpset *vpset = &this_cpu(hypercall_vpset);
+ struct hv_vpset *set = &vpset->set;
+ size_t size;
+ int rc;
+
+ /* These hypercalls should never use the fast-call convention. */
+ if ( input->fast )
+ return -EINVAL;
+
+ /* Get input parameters. */
+ if ( hvm_copy_from_guest_phys(&input_params, input_params_gpa,
+ sizeof(input_params)) != HVMTRANS_okay )
+ return -EINVAL;
+
+ if ( input_params.target_vtl ||
+ input_params.reserved_zero[0] ||
+ input_params.reserved_zero[1] ||
+ input_params.reserved_zero[2] )
+ return HV_STATUS_INVALID_PARAMETER;
+
+ if ( input_params.vector < 0x10 || input_params.vector > 0xff )
+ return HV_STATUS_INVALID_PARAMETER;
+
+ *set = input_params.set;
+ if ( set->format == HV_GENERIC_SET_SPARSE_4K )
+ {
+ unsigned long offset = offsetof(typeof(input_params),
+ set.bank_contents);
+
+ size = sizeof(*set->bank_contents) * hv_vpset_nr_banks(set);
+
+ if ( offsetof(typeof(*vpset), set.bank_contents[0]) + size >
+ sizeof(*vpset) )
+ {
+ ASSERT_UNREACHABLE();
+ return -EINVAL;
+ }
+
+ if ( hvm_copy_from_guest_phys(&set->bank_contents,
+ input_params_gpa + offset,
+ size) != HVMTRANS_okay)
+ return -EINVAL;
+
+ size += sizeof(*set);
+ }
+ else
+ size = sizeof(*set);
+
+ rc = hv_vpset_to_vpmask(set, vpmask);
+ if ( rc )
+ return rc;
+
+ send_ipi(vpmask, input_params.vector);
+
+ return 0;
+}
+
int viridian_hypercall(struct cpu_user_regs *regs)
{
struct vcpu *curr = current;
@@ -916,6 +985,11 @@ int viridian_hypercall(struct cpu_user_regs *regs)
output_params_gpa);
break;

+ case HVCALL_SEND_IPI_EX:
+ rc = hvcall_ipi_ex(&input, &output, input_params_gpa,
+ output_params_gpa);
+ break;
+
default:
gprintk(XENLOG_WARNING, "unimplemented hypercall %04x\n",
input.call_code);
--
2.20.1