zircon/kernel/dev/iommu/intel/iommu_page.cc

// Copyright 2018 The Fuchsia Authors
//
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file or at
// https://opensource.org/licenses/MIT

#include "iommu_page.h"

#include <vm/pmm.h>
#include <vm/vm_aspace.h>

namespace intel_iommu {

IommuPage::IommuPage(vm_page_t* page, uintptr_t virt) : page_(page), virt_(virt) {}

IommuPage::~IommuPage() {
  if (page_) {
    VmAspace::kernel_aspace()->FreeRegion(reinterpret_cast<vaddr_t>(virt_));
    pmm_free_page(page_);
  }
}

zx_status_t IommuPage::AllocatePage(IommuPage* out) {
  vm_page_t* page;
  zx_status_t status = pmm_alloc_page(0, &page);
  if (status != ZX_OK) {
    return status;
  }
  page->set_state(vm_page_state::IOMMU);

  void* vaddr;
  auto kernel_aspace = VmAspace::kernel_aspace();
  status = kernel_aspace->AllocPhysical("iommu_ctx_tbl", PAGE_SIZE, &vaddr, PAGE_SIZE_SHIFT,
                                        page->paddr(), 0,
                                        ARCH_MMU_FLAG_PERM_READ | ARCH_MMU_FLAG_PERM_WRITE);
  if (status != ZX_OK) {
    pmm_free_page(page);
    return status;
  }

  arch_zero_page(vaddr);

  *out = IommuPage(page, reinterpret_cast<uintptr_t>(vaddr));
  return ZX_OK;
}

}  // namespace intel_iommu