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Diffstat (limited to 'drivers/iommu/iommu.c')
-rw-r--r--drivers/iommu/iommu.c119
1 files changed, 107 insertions, 12 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 5b5fa5cdaa31..14d6f908196b 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -16,6 +16,8 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/bug.h>
@@ -157,32 +159,125 @@ int iommu_domain_has_cap(struct iommu_domain *domain,
EXPORT_SYMBOL_GPL(iommu_domain_has_cap);
int iommu_map(struct iommu_domain *domain, unsigned long iova,
- phys_addr_t paddr, int gfp_order, int prot)
+ phys_addr_t paddr, size_t size, int prot)
{
- size_t size;
+ unsigned long orig_iova = iova;
+ unsigned int min_pagesz;
+ size_t orig_size = size;
+ int ret = 0;
if (unlikely(domain->ops->map == NULL))
return -ENODEV;
- size = PAGE_SIZE << gfp_order;
+ /* find out the minimum page size supported */
+ min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap);
+
+ /*
+ * both the virtual address and the physical one, as well as
+ * the size of the mapping, must be aligned (at least) to the
+ * size of the smallest page supported by the hardware
+ */
+ if (!IS_ALIGNED(iova | paddr | size, min_pagesz)) {
+ pr_err("unaligned: iova 0x%lx pa 0x%lx size 0x%lx min_pagesz "
+ "0x%x\n", iova, (unsigned long)paddr,
+ (unsigned long)size, min_pagesz);
+ return -EINVAL;
+ }
+
+ pr_debug("map: iova 0x%lx pa 0x%lx size 0x%lx\n", iova,
+ (unsigned long)paddr, (unsigned long)size);
+
+ while (size) {
+ unsigned long pgsize, addr_merge = iova | paddr;
+ unsigned int pgsize_idx;
+
+ /* Max page size that still fits into 'size' */
+ pgsize_idx = __fls(size);
+
+ /* need to consider alignment requirements ? */
+ if (likely(addr_merge)) {
+ /* Max page size allowed by both iova and paddr */
+ unsigned int align_pgsize_idx = __ffs(addr_merge);
+
+ pgsize_idx = min(pgsize_idx, align_pgsize_idx);
+ }
+
+ /* build a mask of acceptable page sizes */
+ pgsize = (1UL << (pgsize_idx + 1)) - 1;
+
+ /* throw away page sizes not supported by the hardware */
+ pgsize &= domain->ops->pgsize_bitmap;
- BUG_ON(!IS_ALIGNED(iova | paddr, size));
+ /* make sure we're still sane */
+ BUG_ON(!pgsize);
- return domain->ops->map(domain, iova, paddr, gfp_order, prot);
+ /* pick the biggest page */
+ pgsize_idx = __fls(pgsize);
+ pgsize = 1UL << pgsize_idx;
+
+ pr_debug("mapping: iova 0x%lx pa 0x%lx pgsize %lu\n", iova,
+ (unsigned long)paddr, pgsize);
+
+ ret = domain->ops->map(domain, iova, paddr, pgsize, prot);
+ if (ret)
+ break;
+
+ iova += pgsize;
+ paddr += pgsize;
+ size -= pgsize;
+ }
+
+ /* unroll mapping in case something went wrong */
+ if (ret)
+ iommu_unmap(domain, orig_iova, orig_size - size);
+
+ return ret;
}
EXPORT_SYMBOL_GPL(iommu_map);
-int iommu_unmap(struct iommu_domain *domain, unsigned long iova, int gfp_order)
+size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size)
{
- size_t size;
+ size_t unmapped_page, unmapped = 0;
+ unsigned int min_pagesz;
if (unlikely(domain->ops->unmap == NULL))
return -ENODEV;
- size = PAGE_SIZE << gfp_order;
-
- BUG_ON(!IS_ALIGNED(iova, size));
-
- return domain->ops->unmap(domain, iova, gfp_order);
+ /* find out the minimum page size supported */
+ min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap);
+
+ /*
+ * The virtual address, as well as the size of the mapping, must be
+ * aligned (at least) to the size of the smallest page supported
+ * by the hardware
+ */
+ if (!IS_ALIGNED(iova | size, min_pagesz)) {
+ pr_err("unaligned: iova 0x%lx size 0x%lx min_pagesz 0x%x\n",
+ iova, (unsigned long)size, min_pagesz);
+ return -EINVAL;
+ }
+
+ pr_debug("unmap this: iova 0x%lx size 0x%lx\n", iova,
+ (unsigned long)size);
+
+ /*
+ * Keep iterating until we either unmap 'size' bytes (or more)
+ * or we hit an area that isn't mapped.
+ */
+ while (unmapped < size) {
+ size_t left = size - unmapped;
+
+ unmapped_page = domain->ops->unmap(domain, iova, left);
+ if (!unmapped_page)
+ break;
+
+ pr_debug("unmapped: iova 0x%lx size %lx\n", iova,
+ (unsigned long)unmapped_page);
+
+ iova += unmapped_page;
+ unmapped += unmapped_page;
+ }
+
+ return unmapped;
}
EXPORT_SYMBOL_GPL(iommu_unmap);