Commit 5ea11f2b authored by Suravee Suthikulpanit's avatar Suravee Suthikulpanit Committed by Paolo Bonzini

svm: Introduces AVIC per-VM ID

Introduces per-VM AVIC ID and helper functions to manage the IDs.
Currently, the ID will be used to implement 32-bit AVIC IOMMU GA tag.

The ID is 24-bit one-based indexing value, and is managed via helper
functions to get the next ID, or to free an ID once a VM is destroyed.
There should be no ID conflict for any active VMs.
Reviewed-by: default avatarRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: default avatarSuravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 9ac7e3e8
......@@ -781,6 +781,7 @@ struct kvm_arch {
bool disabled_lapic_found;
/* Struct members for AVIC */
u32 avic_vm_id;
u32 ldr_mode;
struct page *avic_logical_id_table_page;
struct page *avic_physical_id_table_page;
......
......@@ -96,6 +96,19 @@ MODULE_DEVICE_TABLE(x86cpu, svm_cpu_id);
#define AVIC_UNACCEL_ACCESS_OFFSET_MASK 0xFF0
#define AVIC_UNACCEL_ACCESS_VECTOR_MASK 0xFFFFFFFF
/* AVIC GATAG is encoded using VM and VCPU IDs */
#define AVIC_VCPU_ID_BITS 8
#define AVIC_VCPU_ID_MASK ((1 << AVIC_VCPU_ID_BITS) - 1)
#define AVIC_VM_ID_BITS 24
#define AVIC_VM_ID_NR (1 << AVIC_VM_ID_BITS)
#define AVIC_VM_ID_MASK ((1 << AVIC_VM_ID_BITS) - 1)
#define AVIC_GATAG(x, y) (((x & AVIC_VM_ID_MASK) << AVIC_VCPU_ID_BITS) | \
(y & AVIC_VCPU_ID_MASK))
#define AVIC_GATAG_TO_VMID(x) ((x >> AVIC_VCPU_ID_BITS) & AVIC_VM_ID_MASK)
#define AVIC_GATAG_TO_VCPUID(x) (x & AVIC_VCPU_ID_MASK)
static bool erratum_383_found __read_mostly;
static const u32 host_save_user_msrs[] = {
......@@ -242,6 +255,10 @@ static int avic;
module_param(avic, int, S_IRUGO);
#endif
/* AVIC VM ID bit masks and lock */
static DECLARE_BITMAP(avic_vm_id_bitmap, AVIC_VM_ID_NR);
static DEFINE_SPINLOCK(avic_vm_id_lock);
static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0);
static void svm_flush_tlb(struct kvm_vcpu *vcpu);
static void svm_complete_interrupts(struct vcpu_svm *svm);
......@@ -1280,10 +1297,40 @@ static int avic_init_backing_page(struct kvm_vcpu *vcpu)
return 0;
}
static inline int avic_get_next_vm_id(void)
{
int id;
spin_lock(&avic_vm_id_lock);
/* AVIC VM ID is one-based. */
id = find_next_zero_bit(avic_vm_id_bitmap, AVIC_VM_ID_NR, 1);
if (id <= AVIC_VM_ID_MASK)
__set_bit(id, avic_vm_id_bitmap);
else
id = -EAGAIN;
spin_unlock(&avic_vm_id_lock);
return id;
}
static inline int avic_free_vm_id(int id)
{
if (id <= 0 || id > AVIC_VM_ID_MASK)
return -EINVAL;
spin_lock(&avic_vm_id_lock);
__clear_bit(id, avic_vm_id_bitmap);
spin_unlock(&avic_vm_id_lock);
return 0;
}
static void avic_vm_destroy(struct kvm *kvm)
{
struct kvm_arch *vm_data = &kvm->arch;
avic_free_vm_id(vm_data->avic_vm_id);
if (vm_data->avic_logical_id_table_page)
__free_page(vm_data->avic_logical_id_table_page);
if (vm_data->avic_physical_id_table_page)
......@@ -1300,6 +1347,10 @@ static int avic_vm_init(struct kvm *kvm)
if (!avic)
return 0;
vm_data->avic_vm_id = avic_get_next_vm_id();
if (vm_data->avic_vm_id < 0)
return vm_data->avic_vm_id;
/* Allocating physical APIC ID table (4KB) */
p_page = alloc_page(GFP_KERNEL);
if (!p_page)
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment