@@ -584,7 +584,7 @@ struct kvm_vcpu_arch {
pgd_t *pgdir;
u8 io_gpr; /* GPR used as IO source/target */
- u8 mmio_is_bigendian;
+ u8 mmio_host_swabbed;
u8 mmio_sign_extend;
u8 osi_needed;
u8 osi_enabled;
@@ -721,7 +721,7 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu,
return;
}
- if (vcpu->arch.mmio_is_bigendian) {
+ if (!vcpu->arch.mmio_host_swabbed) {
switch (run->mmio.len) {
case 8: gpr = *(u64 *)run->mmio.data; break;
case 4: gpr = *(u32 *)run->mmio.data; break;
@@ -729,10 +729,10 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu,
case 1: gpr = *(u8 *)run->mmio.data; break;
}
} else {
- /* Convert BE data from userland back to LE. */
switch (run->mmio.len) {
- case 4: gpr = ld_le32((u32 *)run->mmio.data); break;
- case 2: gpr = ld_le16((u16 *)run->mmio.data); break;
+ case 8: gpr = swab64(*(u64 *)run->mmio.data); break;
+ case 4: gpr = swab32(*(u32 *)run->mmio.data); break;
+ case 2: gpr = swab16(*(u16 *)run->mmio.data); break;
case 1: gpr = *(u8 *)run->mmio.data; break;
}
}
@@ -781,14 +781,13 @@ int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
int is_default_endian)
{
int idx, ret;
- int is_bigendian;
+ bool host_swabbed;
+ /* Pity C doesn't have a logical XOR operator */
if (kvmppc_need_byteswap(vcpu)) {
- /* Default endianness is "little endian". */
- is_bigendian = !is_default_endian;
+ host_swabbed = is_default_endian;
} else {
- /* Default endianness is "big endian". */
- is_bigendian = is_default_endian;
+ host_swabbed = !is_default_endian;
}
if (bytes > sizeof(run->mmio.data)) {
@@ -801,7 +800,7 @@ int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
run->mmio.is_write = 0;
vcpu->arch.io_gpr = rt;
- vcpu->arch.mmio_is_bigendian = is_bigendian;
+ vcpu->arch.mmio_host_swabbed = host_swabbed;
vcpu->mmio_needed = 1;
vcpu->mmio_is_write = 0;
vcpu->arch.mmio_sign_extend = 0;
@@ -841,14 +840,13 @@ int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
{
void *data = run->mmio.data;
int idx, ret;
- int is_bigendian;
+ bool host_swabbed;
+ /* Pity C doesn't have a logical XOR operator */
if (kvmppc_need_byteswap(vcpu)) {
- /* Default endianness is "little endian". */
- is_bigendian = !is_default_endian;
+ host_swabbed = is_default_endian;
} else {
- /* Default endianness is "big endian". */
- is_bigendian = is_default_endian;
+ host_swabbed = !is_default_endian;
}
if (bytes > sizeof(run->mmio.data)) {
@@ -863,7 +861,7 @@ int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
vcpu->mmio_is_write = 1;
/* Store the value at the lowest bytes in 'data'. */
- if (is_bigendian) {
+ if (!host_swabbed) {
switch (bytes) {
case 8: *(u64 *)data = val; break;
case 4: *(u32 *)data = val; break;
@@ -871,11 +869,11 @@ int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
case 1: *(u8 *)data = val; break;
}
} else {
- /* Store LE value into 'data'. */
switch (bytes) {
- case 4: st_le32(data, val); break;
- case 2: st_le16(data, val); break;
- case 1: *(u8 *)data = val; break;
+ case 8: *(u64 *)data = swab64(val); break;
+ case 4: *(u32 *)data = swab32(val); break;
+ case 2: *(u16 *)data = swab16(val); break;
+ case 1: *(u8 *)data = val; break;
}
}
Sometimes the KVM code on powerpc needs to emulate load or store instructions from the guest, which can include both normal and byte reversed forms. We currently (AFAICT) handle this correctly, but some variable names are very misleading. In particular we use "is_bigendian" in several places to actually mean "is the IO the same endian as the host", but we now support little-endian powerpc hosts. This also ties into the misleadingly named ld_le*() and st_le*() functions, which in fact always byteswap, even on an LE host. This patch cleans this up by renaming to more accurate "host_swabbed", and uses the generic swab*() functions instead of the powerpc specific and misleadingly named ld_le*() and st_le*() functions. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> --- arch/powerpc/include/asm/kvm_host.h | 2 +- arch/powerpc/kvm/powerpc.c | 38 ++++++++++++++++++------------------- 2 files changed, 19 insertions(+), 21 deletions(-)