amd-iommu: move page table allocation code to seperate function
This patch makes page table allocation usable for dma_ops code.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 62acd09..ded79f7 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -55,7 +55,9 @@
static int dma_ops_unity_map(struct dma_ops_domain *dma_dom,
struct unity_map_entry *e);
static struct dma_ops_domain *find_protection_domain(u16 devid);
-
+static u64* alloc_pte(struct protection_domain *dom,
+ unsigned long address, u64
+ **pte_page, gfp_t gfp);
#ifdef CONFIG_AMD_IOMMU_STATS
@@ -468,7 +470,7 @@
unsigned long phys_addr,
int prot)
{
- u64 __pte, *pte, *page;
+ u64 __pte, *pte;
bus_addr = PAGE_ALIGN(bus_addr);
phys_addr = PAGE_ALIGN(phys_addr);
@@ -477,27 +479,7 @@
if (bus_addr > IOMMU_MAP_SIZE_L3 || !(prot & IOMMU_PROT_MASK))
return -EINVAL;
- pte = &dom->pt_root[IOMMU_PTE_L2_INDEX(bus_addr)];
-
- if (!IOMMU_PTE_PRESENT(*pte)) {
- page = (u64 *)get_zeroed_page(GFP_KERNEL);
- if (!page)
- return -ENOMEM;
- *pte = IOMMU_L2_PDE(virt_to_phys(page));
- }
-
- pte = IOMMU_PTE_PAGE(*pte);
- pte = &pte[IOMMU_PTE_L1_INDEX(bus_addr)];
-
- if (!IOMMU_PTE_PRESENT(*pte)) {
- page = (u64 *)get_zeroed_page(GFP_KERNEL);
- if (!page)
- return -ENOMEM;
- *pte = IOMMU_L1_PDE(virt_to_phys(page));
- }
-
- pte = IOMMU_PTE_PAGE(*pte);
- pte = &pte[IOMMU_PTE_L0_INDEX(bus_addr)];
+ pte = alloc_pte(dom, bus_addr, NULL, GFP_KERNEL);
if (IOMMU_PTE_PRESENT(*pte))
return -EBUSY;
@@ -1140,6 +1122,61 @@
}
/*
+ * If the pte_page is not yet allocated this function is called
+ */
+static u64* alloc_pte(struct protection_domain *dom,
+ unsigned long address, u64 **pte_page, gfp_t gfp)
+{
+ u64 *pte, *page;
+
+ pte = &dom->pt_root[IOMMU_PTE_L2_INDEX(address)];
+
+ if (!IOMMU_PTE_PRESENT(*pte)) {
+ page = (u64 *)get_zeroed_page(gfp);
+ if (!page)
+ return NULL;
+ *pte = IOMMU_L2_PDE(virt_to_phys(page));
+ }
+
+ pte = IOMMU_PTE_PAGE(*pte);
+ pte = &pte[IOMMU_PTE_L1_INDEX(address)];
+
+ if (!IOMMU_PTE_PRESENT(*pte)) {
+ page = (u64 *)get_zeroed_page(gfp);
+ if (!page)
+ return NULL;
+ *pte = IOMMU_L1_PDE(virt_to_phys(page));
+ }
+
+ pte = IOMMU_PTE_PAGE(*pte);
+
+ if (pte_page)
+ *pte_page = pte;
+
+ pte = &pte[IOMMU_PTE_L0_INDEX(address)];
+
+ return pte;
+}
+
+/*
+ * This function fetches the PTE for a given address in the aperture
+ */
+static u64* dma_ops_get_pte(struct dma_ops_domain *dom,
+ unsigned long address)
+{
+ struct aperture_range *aperture = &dom->aperture;
+ u64 *pte, *pte_page;
+
+ pte = aperture->pte_pages[IOMMU_PTE_L1_INDEX(address)];
+ if (!pte) {
+ pte = alloc_pte(&dom->domain, address, &pte_page, GFP_ATOMIC);
+ aperture->pte_pages[IOMMU_PTE_L1_INDEX(address)] = pte_page;
+ }
+
+ return pte;
+}
+
+/*
* This is the generic map function. It maps one 4kb page at paddr to
* the given address in the DMA address space for the domain.
*/
@@ -1155,8 +1192,7 @@
paddr &= PAGE_MASK;
- pte = dom->aperture.pte_pages[IOMMU_PTE_L1_INDEX(address)];
- pte += IOMMU_PTE_L0_INDEX(address);
+ pte = dma_ops_get_pte(dom, address);
__pte = paddr | IOMMU_PTE_P | IOMMU_PTE_FC;