Commit f41389ae authored by Eric Auger's avatar Eric Auger Committed by Paolo Bonzini
Browse files

KVM_CAP_IRQFD and KVM_CAP_IRQFD_RESAMPLE checks 



Compute kvm_irqfds_allowed by checking the KVM_CAP_IRQFD extension.
Remove direct settings in architecture specific files.

Add a new kvm_resamplefds_allowed variable, initialized by
checking the KVM_CAP_IRQFD_RESAMPLE extension. Add a corresponding
kvm_resamplefds_enabled() function.

A special notice for s390 where KVM_CAP_IRQFD was not immediatly
advirtised when irqfd capability was introduced in the kernel.
KVM_CAP_IRQ_ROUTING was advertised instead.

This was fixed in "KVM: s390: announce irqfd capability",
ebc3226202d5956a5963185222982d435378b899 whereas irqfd support
was brought in 84223598778ba08041f4297fda485df83414d57e,
"KVM: s390: irq routing for adapter interrupts".  Both commits
first appear in 3.15 so there should not be any kernel
version impacted by this QEMU modification.

Signed-off-by: default avatarEric Auger <eric.auger@linaro.org>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 9551ea69

hw/intc/openpic_kvm.c

+0 −1
Original line number Diff line number Diff line
@@ -248,7 +248,6 @@ static void kvm_openpic_realize(DeviceState *dev, Error **errp) 
        kvm_irqchip_add_irq_route(kvm_state, i, 0, i);

    }



    kvm_irqfds_allowed = true;

    kvm_msi_via_irqfd_allowed = true;

    kvm_gsi_routing_allowed = true;

hw/intc/xics_kvm.c

+0 −1
Original line number Diff line number Diff line
@@ -448,7 +448,6 @@ static void xics_kvm_realize(DeviceState *dev, Error **errp) 
    }



    kvm_kernel_irqchip = true;

    kvm_irqfds_allowed = true;

    kvm_msi_via_irqfd_allowed = true;

    kvm_gsi_direct_mapping = true;

include/sysemu/kvm.h

+10 −0
Original line number Diff line number Diff line
@@ -45,6 +45,7 @@ extern bool kvm_async_interrupts_allowed; 
extern bool kvm_halt_in_kernel_allowed;

extern bool kvm_eventfds_allowed;

extern bool kvm_irqfds_allowed;

extern bool kvm_resamplefds_allowed;

extern bool kvm_msi_via_irqfd_allowed;

extern bool kvm_gsi_routing_allowed;

extern bool kvm_gsi_direct_mapping;
@@ -101,6 +102,15 @@ extern bool kvm_readonly_mem_allowed; 
 */

#define kvm_irqfds_enabled() (kvm_irqfds_allowed)



/**

 * kvm_resamplefds_enabled:

 *

 * Returns: true if we can use resamplefds to inject interrupts into

 * a KVM CPU (ie the kernel supports resamplefds and we are running

 * with a configuration where it is meaningful to use them).

 */

#define kvm_resamplefds_enabled() (kvm_resamplefds_allowed)



/**

 * kvm_msi_via_irqfd_enabled:

 *

kvm-all.c

+7 −0
Original line number Diff line number Diff line
@@ -120,6 +120,7 @@ bool kvm_async_interrupts_allowed; 
bool kvm_halt_in_kernel_allowed;

bool kvm_eventfds_allowed;

bool kvm_irqfds_allowed;

bool kvm_resamplefds_allowed;

bool kvm_msi_via_irqfd_allowed;

bool kvm_gsi_routing_allowed;

bool kvm_gsi_direct_mapping;
@@ -1584,6 +1585,12 @@ static int kvm_init(MachineState *ms) 
    kvm_eventfds_allowed =

        (kvm_check_extension(s, KVM_CAP_IOEVENTFD) > 0);



    kvm_irqfds_allowed =

        (kvm_check_extension(s, KVM_CAP_IRQFD) > 0);



    kvm_resamplefds_allowed =

        (kvm_check_extension(s, KVM_CAP_IRQFD_RESAMPLE) > 0);



    ret = kvm_arch_init(s);

    if (ret < 0) {

        goto err;

target-i386/kvm.c

+0 −1
Original line number Diff line number Diff line
@@ -2563,7 +2563,6 @@ void kvm_arch_init_irq_routing(KVMState *s) 
     * irqchip, so we can use irqfds, and on x86 we know

     * we can use msi via irqfd and GSI routing.

     */

    kvm_irqfds_allowed = true;

    kvm_msi_via_irqfd_allowed = true;

    kvm_gsi_routing_allowed = true;

}