diff options
author | Marc Zyngier <maz@kernel.org> | 2019-12-13 16:25:25 +0300 |
---|---|---|
committer | Marc Zyngier <maz@kernel.org> | 2020-01-23 13:38:14 +0300 |
commit | 0e20f5e25556c00ee813469d373b00abcf298708 (patch) | |
tree | 3503fff95c58e755c203374e037fc445f1c678cf /virt/kvm | |
parent | 31a9b0b11b1c5264433a4fa1e1e1e8aa03954b1c (diff) | |
download | linux-0e20f5e25556c00ee813469d373b00abcf298708.tar.xz |
KVM: arm/arm64: Cleanup MMIO handling
Our MMIO handling is a bit odd, in the sense that it uses an
intermediate per-vcpu structure to store the various decoded
information that describe the access.
But the same information is readily available in the HSR/ESR_EL2
field, and we actually use this field to populate the structure.
Let's simplify the whole thing by getting rid of the superfluous
structure and save a (tiny) bit of space in the vcpu structure.
[32bit fix courtesy of Olof Johansson <olof@lixom.net>]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'virt/kvm')
-rw-r--r-- | virt/kvm/arm/mmio.c | 70 | ||||
-rw-r--r-- | virt/kvm/arm/mmu.c | 1 |
2 files changed, 22 insertions, 49 deletions
diff --git a/virt/kvm/arm/mmio.c b/virt/kvm/arm/mmio.c index 1bb71acd53f2..aedfcff99ac5 100644 --- a/virt/kvm/arm/mmio.c +++ b/virt/kvm/arm/mmio.c @@ -5,7 +5,6 @@ */ #include <linux/kvm_host.h> -#include <asm/kvm_mmio.h> #include <asm/kvm_emulate.h> #include <trace/events/kvm.h> @@ -92,26 +91,23 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run) vcpu->mmio_needed = 0; - if (!run->mmio.is_write) { - len = run->mmio.len; - if (len > sizeof(unsigned long)) - return -EINVAL; - + if (!kvm_vcpu_dabt_iswrite(vcpu)) { + len = kvm_vcpu_dabt_get_as(vcpu); data = kvm_mmio_read_buf(run->mmio.data, len); - if (vcpu->arch.mmio_decode.sign_extend && + if (kvm_vcpu_dabt_issext(vcpu) && len < sizeof(unsigned long)) { mask = 1U << ((len * 8) - 1); data = (data ^ mask) - mask; } - if (!vcpu->arch.mmio_decode.sixty_four) + if (!kvm_vcpu_dabt_issf(vcpu)) data = data & 0xffffffff; trace_kvm_mmio(KVM_TRACE_MMIO_READ, len, run->mmio.phys_addr, &data); data = vcpu_data_host_to_guest(vcpu, data, len); - vcpu_set_reg(vcpu, vcpu->arch.mmio_decode.rt, data); + vcpu_set_reg(vcpu, kvm_vcpu_dabt_get_rd(vcpu), data); } /* @@ -123,36 +119,6 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run) return 0; } -static int decode_hsr(struct kvm_vcpu *vcpu, bool *is_write, int *len) -{ - unsigned long rt; - int access_size; - bool sign_extend; - bool sixty_four; - - if (kvm_vcpu_dabt_iss1tw(vcpu)) { - /* page table accesses IO mem: tell guest to fix its TTBR */ - kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu)); - return 1; - } - - access_size = kvm_vcpu_dabt_get_as(vcpu); - if (unlikely(access_size < 0)) - return access_size; - - *is_write = kvm_vcpu_dabt_iswrite(vcpu); - sign_extend = kvm_vcpu_dabt_issext(vcpu); - sixty_four = kvm_vcpu_dabt_issf(vcpu); - rt = kvm_vcpu_dabt_get_rd(vcpu); - - *len = access_size; - vcpu->arch.mmio_decode.sign_extend = sign_extend; - vcpu->arch.mmio_decode.rt = rt; - vcpu->arch.mmio_decode.sixty_four = sixty_four; - - return 0; -} - int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run, phys_addr_t fault_ipa) { @@ -164,15 +130,10 @@ int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run, u8 data_buf[8]; /* - * Prepare MMIO operation. First decode the syndrome data we get - * from the CPU. Then try if some in-kernel emulation feels - * responsible, otherwise let user space do its magic. + * No valid syndrome? Ask userspace for help if it has + * voluntered to do so, and bail out otherwise. */ - if (kvm_vcpu_dabt_isvalid(vcpu)) { - ret = decode_hsr(vcpu, &is_write, &len); - if (ret) - return ret; - } else { + if (!kvm_vcpu_dabt_isvalid(vcpu)) { if (vcpu->kvm->arch.return_nisv_io_abort_to_user) { run->exit_reason = KVM_EXIT_ARM_NISV; run->arm_nisv.esr_iss = kvm_vcpu_dabt_iss_nisv_sanitized(vcpu); @@ -184,7 +145,20 @@ int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run, return -ENOSYS; } - rt = vcpu->arch.mmio_decode.rt; + /* Page table accesses IO mem: tell guest to fix its TTBR */ + if (kvm_vcpu_dabt_iss1tw(vcpu)) { + kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu)); + return 1; + } + + /* + * Prepare MMIO operation. First decode the syndrome data we get + * from the CPU. Then try if some in-kernel emulation feels + * responsible, otherwise let user space do its magic. + */ + is_write = kvm_vcpu_dabt_iswrite(vcpu); + len = kvm_vcpu_dabt_get_as(vcpu); + rt = kvm_vcpu_dabt_get_rd(vcpu); if (is_write) { data = vcpu_data_guest_to_host(vcpu, vcpu_get_reg(vcpu, rt), diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index e3ad95013192..a4fa81d75e84 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -14,7 +14,6 @@ #include <asm/cacheflush.h> #include <asm/kvm_arm.h> #include <asm/kvm_mmu.h> -#include <asm/kvm_mmio.h> #include <asm/kvm_ras.h> #include <asm/kvm_asm.h> #include <asm/kvm_emulate.h> |