/**
* intel_vgpu_emulate_mmio_write - emulate MMIO write
* @vgpu: a vGPU
* @pa: guest physical address
* @p_data: write data buffer
* @bytes: access data length
*
* Returns:
* Zero on success, negative error code if failed
*/
int intel_vgpu_emulate_mmio_write(struct intel_vgpu *vgpu, u64 pa,
void *p_data, unsigned int bytes)
{
struct intel_gvt *gvt = vgpu->gvt;
unsigned int offset = 0;
int ret = -EINVAL;
if (vgpu->failsafe) {
failsafe_emulate_mmio_rw(vgpu, pa, p_data, bytes, false);
return 0;
}
mutex_lock(&vgpu->vgpu_lock);
offset = intel_vgpu_gpa_to_mmio_offset(vgpu, pa);
if (WARN_ON(bytes > 8))
goto err;
if (reg_is_gtt(gvt, offset)) {
if (WARN_ON(!IS_ALIGNED(offset, 4) && !IS_ALIGNED(offset, 8)))
goto err;
if (WARN_ON(bytes != 4 && bytes != 8))
goto err;
if (WARN_ON(!reg_is_gtt(gvt, offset + bytes - 1)))
goto err;
ret = intel_vgpu_emulate_ggtt_mmio_write(vgpu, offset,
p_data, bytes);
if (ret)
goto err;
goto out;
}
if (WARN_ON_ONCE(!reg_is_mmio(gvt, offset))) {
ret = intel_gvt_hypervisor_write_gpa(vgpu, pa, p_data, bytes);
goto out;
}
ret = intel_vgpu_mmio_reg_rw(vgpu, offset, p_data, bytes, false);
if (ret < 0)
goto err;
intel_gvt_mmio_set_accessed(gvt, offset);
ret = 0;
goto out;
err:
gvt_vgpu_err("fail to emulate MMIO write %08x len %d\n", offset,
bytes);
out:
mutex_unlock(&vgpu->vgpu_lock);
return ret;
}
/**
* intel_vgpu_emulate_mmio_read - emulate MMIO read
* @vgpu: a vGPU
* @pa: guest physical address
* @p_data: data return buffer
* @bytes: access data length
*
* Returns:
* Zero on success, negative error code if failed
*/
int intel_vgpu_emulate_mmio_read(struct intel_vgpu *vgpu, uint64_t pa,
void *p_data, unsigned int bytes)
{
struct intel_gvt *gvt = vgpu->gvt;
struct intel_gvt_mmio_info *mmio;
unsigned int offset = 0;
int ret = -EINVAL;
mutex_lock(&gvt->lock);
if (atomic_read(&vgpu->gtt.n_write_protected_guest_page)) {
struct intel_vgpu_guest_page *gp;
gp = intel_vgpu_find_guest_page(vgpu, pa >> PAGE_SHIFT);
if (gp) {
ret = intel_gvt_hypervisor_read_gpa(vgpu, pa,
p_data, bytes);
if (ret) {
gvt_err("vgpu%d: guest page read error %d, "
"gfn 0x%lx, pa 0x%llx, var 0x%x, len %d\n",
vgpu->id, ret,
gp->gfn, pa, *(u32 *)p_data, bytes);
}
mutex_unlock(&gvt->lock);
return ret;
}
}
offset = intel_vgpu_gpa_to_mmio_offset(vgpu, pa);
if (WARN_ON(bytes > 8))
goto err;
if (reg_is_gtt(gvt, offset)) {
if (WARN_ON(!IS_ALIGNED(offset, 4) && !IS_ALIGNED(offset, 8)))
goto err;
if (WARN_ON(bytes != 4 && bytes != 8))
goto err;
if (WARN_ON(!reg_is_gtt(gvt, offset + bytes - 1)))
goto err;
ret = intel_vgpu_emulate_gtt_mmio_read(vgpu, offset,
p_data, bytes);
if (ret)
goto err;
mutex_unlock(&gvt->lock);
return ret;
}
if (WARN_ON_ONCE(!reg_is_mmio(gvt, offset))) {
ret = intel_gvt_hypervisor_read_gpa(vgpu, pa, p_data, bytes);
mutex_unlock(&gvt->lock);
return ret;
}
if (WARN_ON(!reg_is_mmio(gvt, offset + bytes - 1)))
goto err;
mmio = intel_gvt_find_mmio_info(gvt, rounddown(offset, 4));
if (!mmio && !vgpu->mmio.disable_warn_untrack) {
gvt_err("vgpu%d: read untracked MMIO %x len %d val %x\n",
vgpu->id, offset, bytes, *(u32 *)p_data);
if (offset == 0x206c) {
gvt_err("------------------------------------------\n");
gvt_err("vgpu%d: likely triggers a gfx reset\n",
vgpu->id);
gvt_err("------------------------------------------\n");
vgpu->mmio.disable_warn_untrack = true;
}
}
if (!intel_gvt_mmio_is_unalign(gvt, offset)) {
if (WARN_ON(!IS_ALIGNED(offset, bytes)))
goto err;
}
if (mmio) {
if (!intel_gvt_mmio_is_unalign(gvt, mmio->offset)) {
if (WARN_ON(offset + bytes > mmio->offset + mmio->size))
goto err;
if (WARN_ON(mmio->offset != offset))
goto err;
}
ret = mmio->read(vgpu, offset, p_data, bytes);
} else
ret = intel_vgpu_default_mmio_read(vgpu, offset, p_data, bytes);
if (ret)
goto err;
intel_gvt_mmio_set_accessed(gvt, offset);
mutex_unlock(&gvt->lock);
return 0;
err:
gvt_err("vgpu%d: fail to emulate MMIO read %08x len %d\n",
vgpu->id, offset, bytes);
mutex_unlock(&gvt->lock);
return ret;
}