[PATCH 07/11] x86/amd-iommu: Make iommu_map_page and alloc_pte aware of page sizes

Joerg Roedel
2010-01-28T11:37:58Z

This patch changes the old map_size parameter of alloc_pte
to a page_size parameter which can be used more easily to
alloc a pte for intermediate page sizes.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
arch/x86/include/asm/amd_iommu_types.h | 28 +++++++++++++++++
arch/x86/kernel/amd_iommu.c | 53 ++++++++++++++++++++------------
2 files changed, 61 insertions(+), 20 deletions(-)

diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h
index ba19ad4..5e8da56 100644
--- a/arch/x86/include/asm/amd_iommu_types.h
+++ b/arch/x86/include/asm/amd_iommu_types.h
@@ -172,6 +172,34 @@
(~((1ULL << (12 + ((lvl) * 9))) - 1)))
#define PM_ALIGNED(lvl, addr) ((PM_MAP_MASK(lvl) & (addr)) == (addr))

+/*
+ * Returns the page table level to use for a given page size
+ * Pagesize is expected to be a power-of-two
+ */
+#define PAGE_SIZE_LEVEL(pagesize) \
+ ((__ffs(pagesize) - 12) / 9)
+/*
+ * Returns the number of ptes to use for a given page size
+ * Pagesize is expected to be a power-of-two
+ */
+#define PAGE_SIZE_PTE_COUNT(pagesize) \
+ (1ULL << ((__ffs(pagesize) - 12) % 9))
+
+/*
+ * Aligns a given io-virtual address to a given page size
+ * Pagesize is expected to be a power-of-two
+ */
+#define PAGE_SIZE_ALIGN(address, pagesize) \
+ ((address) & ~((pagesize) - 1))
+/*
+ * Creates an IOMMU PTE for an address an a given pagesize
+ * The PTE has no permission bits set
+ * Pagesize is expected to be a power-of-two larger than 4096
+ */
+#define PAGE_SIZE_PTE(address, pagesize) \
+ (((address) | ((pagesize) - 1)) & \
+ (~(pagesize >> 1)) & PM_ADDR_MASK)
+
#define IOMMU_PTE_P (1ULL << 0)
#define IOMMU_PTE_TV (1ULL << 1)
#define IOMMU_PTE_U (1ULL << 59)
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 59cae7c..4170031 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -730,18 +730,22 @@ static bool increase_address_space(struct protection_domain *domain,

static u64 *alloc_pte(struct protection_domain *domain,
unsigned long address,
- int end_lvl,
+ unsigned long page_size,
u64 **pte_page,
gfp_t gfp)
{
+ int level, end_lvl;
u64 *pte, *page;
- int level;
+
+ BUG_ON(!is_power_of_2(page_size));

while (address > PM_LEVEL_SIZE(domain->mode))
increase_address_space(domain, gfp);

- level = domain->mode - 1;
- pte = &domain->pt_root[PM_LEVEL_INDEX(level, address)];
+ level = domain->mode - 1;
+ pte = &domain->pt_root[PM_LEVEL_INDEX(level, address)];
+ address = PAGE_SIZE_ALIGN(address, page_size);
+ end_lvl = PAGE_SIZE_LEVEL(page_size);

while (level > end_lvl) {
if (!IOMMU_PTE_PRESENT(*pte)) {
@@ -751,6 +755,10 @@ static u64 *alloc_pte(struct protection_domain *domain,
*pte = PM_LEVEL_PDE(level, virt_to_phys(page));
}

+ /* No level skipping support yet */
+ if (PM_PTE_LEVEL(*pte) != level)
+ return NULL;
+
level -= 1;

pte = IOMMU_PTE_PAGE(*pte);
@@ -806,31 +814,36 @@ static int iommu_map_page(struct protection_domain *dom,
unsigned long bus_addr,
unsigned long phys_addr,
int prot,
- int map_size)
+ unsigned long page_size)
{
u64 __pte, *pte;
-
- bus_addr = PAGE_ALIGN(bus_addr);
- phys_addr = PAGE_ALIGN(phys_addr);
-
- BUG_ON(!PM_ALIGNED(map_size, bus_addr));
- BUG_ON(!PM_ALIGNED(map_size, phys_addr));
+ int i, count;

if (!(prot & IOMMU_PROT_MASK))
return -EINVAL;

- pte = alloc_pte(dom, bus_addr, map_size, NULL, GFP_KERNEL);
+ bus_addr = PAGE_ALIGN(bus_addr);
+ phys_addr = PAGE_ALIGN(phys_addr);
+ count = PAGE_SIZE_PTE_COUNT(page_size);
+ pte = alloc_pte(dom, bus_addr, page_size, NULL, GFP_KERNEL);
+
+ for (i = 0; i < count; ++i)
+ if (IOMMU_PTE_PRESENT(pte[i]))
+ return -EBUSY;

- if (IOMMU_PTE_PRESENT(*pte))
- return -EBUSY;
+ if (page_size > PAGE_SIZE) {
+ __pte = PAGE_SIZE_PTE(phys_addr, page_size);
+ __pte |= PM_LEVEL_ENC(7) | IOMMU_PTE_P | IOMMU_PTE_FC;
+ } else
+ __pte = phys_addr | IOMMU_PTE_P | IOMMU_PTE_FC;

- __pte = phys_addr | IOMMU_PTE_P;
if (prot & IOMMU_PROT_IR)
__pte |= IOMMU_PTE_IR;
if (prot & IOMMU_PROT_IW)
__pte |= IOMMU_PTE_IW;

- *pte = __pte;
+ for (i = 0; i < count; ++i)
+ pte[i] = __pte;

update_domain(dom);

@@ -877,7 +890,7 @@ static int dma_ops_unity_map(struct dma_ops_domain *dma_dom,
for (addr = e->address_start; addr < e->address_end;
addr += PAGE_SIZE) {
ret = iommu_map_page(&dma_dom->domain, addr, addr, e->prot,
- PM_MAP_4k);
+ PAGE_SIZE);
if (ret)
return ret;
/*
@@ -1005,7 +1018,7 @@ static int alloc_new_range(struct dma_ops_domain *dma_dom,
u64 *pte, *pte_page;

for (i = 0; i < num_ptes; ++i) {
- pte = alloc_pte(&dma_dom->domain, address, PM_MAP_4k,
+ pte = alloc_pte(&dma_dom->domain, address, PAGE_SIZE,
&pte_page, gfp);
if (!pte)
goto out_free;
@@ -1711,7 +1724,7 @@ static u64* dma_ops_get_pte(struct dma_ops_domain *dom,

pte = aperture->pte_pages[APERTURE_PAGE_INDEX(address)];
if (!pte) {
- pte = alloc_pte(&dom->domain, address, PM_MAP_4k, &pte_page,
+ pte = alloc_pte(&dom->domain, address, PAGE_SIZE, &pte_page,
GFP_ATOMIC);
aperture->pte_pages[APERTURE_PAGE_INDEX(address)] = pte_page;
} else
@@ -2457,7 +2470,7 @@ static int amd_iommu_map_range(struct iommu_domain *dom,
paddr &= PAGE_MASK;

for (i = 0; i < npages; ++i) {
- ret = iommu_map_page(domain, iova, paddr, prot, PM_MAP_4k);
+ ret = iommu_map_page(domain, iova, paddr, prot, PAGE_SIZE);
if (ret)
return ret;

--
1.6.6