From: marc.zyngier@arm•com (Marc Zyngier)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH v5 04/19] arm/arm64: KVM: wrap 64 bit MMIO accesses with two 32 bit ones
Date: Thu, 18 Dec 2014 09:09:05 +0000 [thread overview]
Message-ID: <86tx0t1g0e.fsf@arm.com> (raw)
In-Reply-To: <1418042274-3246-5-git-send-email-andre.przywara@arm.com> (Andre Przywara's message of "Mon, 8 Dec 2014 12:37:39 +0000")
On Mon, Dec 08 2014 at 12:37:39 PM, Andre Przywara <andre.przywara@arm•com> wrote:
> Some GICv3 registers can and will be accessed as 64 bit registers.
> Currently the register handling code can only deal with 32 bit
> accesses, so we do two consecutive calls to cover this.
>
> Signed-off-by: Andre Przywara <andre.przywara@arm•com>
> Reviewed-by: Christoffer Dall <christoffer.dall@linaro•org>
Acked-by: Marc Zyngier <marc.zyngier@arm•com>
> ---
> Changelog v4...v5:
> (add Reviewed-by:)
>
> Changelog v3...v4:
> - add comment explaining little endian handling
>
> virt/kvm/arm/vgic.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++---
> 1 file changed, 50 insertions(+), 3 deletions(-)
>
> diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
> index 9822735..bc2546e 100644
> --- a/virt/kvm/arm/vgic.c
> +++ b/virt/kvm/arm/vgic.c
> @@ -1032,6 +1032,53 @@ static bool vgic_validate_access(const struct vgic_dist *dist,
> return true;
> }
>
> +/*
> + * Call the respective handler function for the given range.
> + * We split up any 64 bit accesses into two consecutive 32 bit
> + * handler calls and merge the result afterwards.
> + * We do this in a little endian fashion regardless of the host's
> + * or guest's endianness, because the GIC is always LE and the rest of
> + * the code (vgic_reg_access) also puts it in a LE fashion already.
> + * At this point we have already identified the handle function, so
> + * range points to that one entry and offset is relative to this.
> + */
> +static bool call_range_handler(struct kvm_vcpu *vcpu,
> + struct kvm_exit_mmio *mmio,
> + unsigned long offset,
> + const struct mmio_range *range)
> +{
> + u32 *data32 = (void *)mmio->data;
> + struct kvm_exit_mmio mmio32;
> + bool ret;
> +
> + if (likely(mmio->len <= 4))
> + return range->handle_mmio(vcpu, mmio, offset);
> +
> + /*
> + * Any access bigger than 4 bytes (that we currently handle in KVM)
> + * is actually 8 bytes long, caused by a 64-bit access
> + */
> +
> + mmio32.len = 4;
> + mmio32.is_write = mmio->is_write;
> +
> + mmio32.phys_addr = mmio->phys_addr + 4;
> + if (mmio->is_write)
> + *(u32 *)mmio32.data = data32[1];
> + ret = range->handle_mmio(vcpu, &mmio32, offset + 4);
> + if (!mmio->is_write)
> + data32[1] = *(u32 *)mmio32.data;
> +
> + mmio32.phys_addr = mmio->phys_addr;
> + if (mmio->is_write)
> + *(u32 *)mmio32.data = data32[0];
> + ret |= range->handle_mmio(vcpu, &mmio32, offset);
> + if (!mmio->is_write)
> + data32[0] = *(u32 *)mmio32.data;
> +
> + return ret;
> +}
> +
> /**
> * vgic_handle_mmio_range - handle an in-kernel MMIO access
> * @vcpu: pointer to the vcpu performing the access
> @@ -1063,10 +1110,10 @@ static bool vgic_handle_mmio_range(struct kvm_vcpu *vcpu, struct kvm_run *run,
> spin_lock(&vcpu->kvm->arch.vgic.lock);
> offset -= range->base;
> if (vgic_validate_access(dist, range, offset)) {
> - updated_state = range->handle_mmio(vcpu, mmio, offset);
> + updated_state = call_range_handler(vcpu, mmio, offset, range);
> } else {
> - vgic_reg_access(mmio, NULL, offset,
> - ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED);
> + if (!mmio->is_write)
> + memset(mmio->data, 0, mmio->len);
> updated_state = false;
> }
> spin_unlock(&vcpu->kvm->arch.vgic.lock);
--
Jazz is not dead. It just smells funny.
next prev parent reply other threads:[~2014-12-18 9:09 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-12-08 12:37 [PATCH v5 00/19] KVM GICv3 emulation Andre Przywara
2014-12-08 12:37 ` [PATCH v5 01/19] arm/arm64: KVM: rework MPIDR assignment and add accessors Andre Przywara
2014-12-08 15:06 ` Mark Rutland
2014-12-08 15:26 ` Andre Przywara
2014-12-18 9:00 ` Marc Zyngier
2014-12-08 12:37 ` [PATCH v5 02/19] arm/arm64: KVM: pass down user space provided GIC type into vGIC code Andre Przywara
2014-12-18 9:03 ` Marc Zyngier
2014-12-08 12:37 ` [PATCH v5 03/19] arm/arm64: KVM: refactor vgic_handle_mmio() function Andre Przywara
2014-12-18 9:06 ` Marc Zyngier
2014-12-08 12:37 ` [PATCH v5 04/19] arm/arm64: KVM: wrap 64 bit MMIO accesses with two 32 bit ones Andre Przywara
2014-12-18 9:09 ` Marc Zyngier [this message]
2014-12-08 12:37 ` [PATCH v5 05/19] arm/arm64: KVM: introduce per-VM ops Andre Przywara
2014-12-13 13:29 ` Christoffer Dall
2014-12-23 11:43 ` Marc Zyngier
2014-12-08 12:37 ` [PATCH v5 06/19] arm/arm64: KVM: move kvm_register_device_ops() into vGIC probing Andre Przywara
2014-12-23 11:57 ` Marc Zyngier
2014-12-08 12:37 ` [PATCH v5 07/19] arm/arm64: KVM: dont rely on a valid GICH base address Andre Przywara
2014-12-23 11:58 ` Marc Zyngier
2014-12-08 12:37 ` [PATCH v5 08/19] arm/arm64: KVM: make the maximum number of vCPUs a per-VM value Andre Przywara
2014-12-13 13:31 ` Christoffer Dall
2014-12-23 12:07 ` Marc Zyngier
2015-01-05 17:34 ` Andre Przywara
2015-01-06 13:29 ` Christoffer Dall
2015-01-06 14:03 ` Andre Przywara
2015-01-06 13:58 ` Peter Maydell
2014-12-08 12:37 ` [PATCH v5 09/19] arm/arm64: KVM: make the value of ICC_SRE_EL1 a per-VM variable Andre Przywara
2014-12-23 12:14 ` Marc Zyngier
2014-12-08 12:37 ` [PATCH v5 10/19] arm/arm64: KVM: refactor MMIO accessors Andre Przywara
2014-12-08 12:37 ` [PATCH v5 11/19] arm/arm64: KVM: refactor/wrap vgic_set/get_attr() Andre Przywara
2014-12-08 12:37 ` [PATCH v5 12/19] arm/arm64: KVM: add vgic.h header file Andre Przywara
2014-12-08 12:37 ` [PATCH v5 13/19] arm/arm64: KVM: split GICv2 specific emulation code from vgic.c Andre Przywara
2014-12-08 12:37 ` [PATCH v5 14/19] arm/arm64: KVM: add opaque private pointer to MMIO data Andre Przywara
2014-12-08 12:37 ` [PATCH v5 15/19] arm/arm64: KVM: add virtual GICv3 distributor emulation Andre Przywara
2014-12-13 13:37 ` Christoffer Dall
2014-12-15 11:32 ` Andre Przywara
2014-12-08 12:37 ` [PATCH v5 16/19] arm64: GICv3: introduce symbolic names for GICv3 ICC_SGI1R_EL1 fields Andre Przywara
2014-12-08 12:37 ` [PATCH v5 17/19] arm64: KVM: add SGI generation register emulation Andre Przywara
2014-12-08 12:37 ` [PATCH v5 18/19] arm/arm64: KVM: enable kernel side of GICv3 emulation Andre Przywara
2014-12-13 13:42 ` Christoffer Dall
2015-01-05 17:58 ` Andre Przywara
2014-12-08 12:37 ` [PATCH v5 19/19] arm/arm64: KVM: allow userland to request a virtual GICv3 Andre Przywara
2014-12-13 13:45 ` Christoffer Dall
2014-12-15 11:50 ` Andre Przywara
2014-12-15 13:02 ` Christoffer Dall
2014-12-13 13:53 ` [PATCH v5 00/19] KVM GICv3 emulation Christoffer Dall
2014-12-15 14:57 ` Andre Przywara
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