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Diffstat (limited to 'arch/x86/kernel/apic/apic.c')
-rw-r--r--arch/x86/kernel/apic/apic.c73
1 files changed, 66 insertions, 7 deletions
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index b3eef1d5c903..6bd20c0de8bc 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -94,6 +94,11 @@ static unsigned int disabled_cpu_apicid __ro_after_init = BAD_APICID;
static int apic_extnmi __ro_after_init = APIC_EXTNMI_BSP;
/*
+ * Hypervisor supports 15 bits of APIC ID in MSI Extended Destination ID
+ */
+static bool virt_ext_dest_id __ro_after_init;
+
+/*
* Map cpu index to physical APIC ID
*/
DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid, BAD_APICID);
@@ -1591,7 +1596,7 @@ static void setup_local_APIC(void)
apic->init_apic_ldr();
#ifdef CONFIG_X86_32
- if (apic->dest_logical) {
+ if (apic->dest_mode_logical) {
int logical_apicid, ldr_apicid;
/*
@@ -1841,20 +1846,34 @@ static __init void try_to_enable_x2apic(int remap_mode)
return;
if (remap_mode != IRQ_REMAP_X2APIC_MODE) {
- /* IR is required if there is APIC ID > 255 even when running
- * under KVM
+ u32 apic_limit = 255;
+
+ /*
+ * Using X2APIC without IR is not architecturally supported
+ * on bare metal but may be supported in guests.
*/
- if (max_physical_apicid > 255 ||
- !x86_init.hyper.x2apic_available()) {
+ if (!x86_init.hyper.x2apic_available()) {
pr_info("x2apic: IRQ remapping doesn't support X2APIC mode\n");
x2apic_disable();
return;
}
/*
- * without IR all CPUs can be addressed by IOAPIC/MSI
- * only in physical mode
+ * If the hypervisor supports extended destination ID in
+ * MSI, that increases the maximum APIC ID that can be
+ * used for non-remapped IRQ domains.
*/
+ if (x86_init.hyper.msi_ext_dest_id()) {
+ virt_ext_dest_id = 1;
+ apic_limit = 32767;
+ }
+
+ /*
+ * Without IR, all CPUs can be addressed by IOAPIC/MSI only
+ * in physical mode, and CPUs with an APIC ID that cannnot
+ * be addressed must not be brought online.
+ */
+ x2apic_set_max_apicid(apic_limit);
x2apic_phys = 1;
}
x2apic_enable();
@@ -2478,6 +2497,46 @@ int hard_smp_processor_id(void)
return read_apic_id();
}
+void __irq_msi_compose_msg(struct irq_cfg *cfg, struct msi_msg *msg,
+ bool dmar)
+{
+ memset(msg, 0, sizeof(*msg));
+
+ msg->arch_addr_lo.base_address = X86_MSI_BASE_ADDRESS_LOW;
+ msg->arch_addr_lo.dest_mode_logical = apic->dest_mode_logical;
+ msg->arch_addr_lo.destid_0_7 = cfg->dest_apicid & 0xFF;
+
+ msg->arch_data.delivery_mode = APIC_DELIVERY_MODE_FIXED;
+ msg->arch_data.vector = cfg->vector;
+
+ msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH;
+ /*
+ * Only the IOMMU itself can use the trick of putting destination
+ * APIC ID into the high bits of the address. Anything else would
+ * just be writing to memory if it tried that, and needs IR to
+ * address APICs which can't be addressed in the normal 32-bit
+ * address range at 0xFFExxxxx. That is typically just 8 bits, but
+ * some hypervisors allow the extended destination ID field in bits
+ * 5-11 to be used, giving support for 15 bits of APIC IDs in total.
+ */
+ if (dmar)
+ msg->arch_addr_hi.destid_8_31 = cfg->dest_apicid >> 8;
+ else if (virt_ext_dest_id && cfg->dest_apicid < 0x8000)
+ msg->arch_addr_lo.virt_destid_8_14 = cfg->dest_apicid >> 8;
+ else
+ WARN_ON_ONCE(cfg->dest_apicid > 0xFF);
+}
+
+u32 x86_msi_msg_get_destid(struct msi_msg *msg, bool extid)
+{
+ u32 dest = msg->arch_addr_lo.destid_0_7;
+
+ if (extid)
+ dest |= msg->arch_addr_hi.destid_8_31 << 8;
+ return dest;
+}
+EXPORT_SYMBOL_GPL(x86_msi_msg_get_destid);
+
/*
* Override the generic EOI implementation with an optimized version.
* Only called during early boot when only one CPU is active and with