From: Will Deacon <[email protected]>
Extend iommu_pgsize() to populate an optional 'count' parameter so that
we can direct unmapping operation to the ->unmap_pages callback if it
has been provided by the driver.
Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Isaac J. Manjarres <[email protected]>
Signed-off-by: Georgi Djakov <[email protected]>
---
drivers/iommu/iommu.c | 59 +++++++++++++++++++++++++++++++++++++++++++--------
1 file changed, 50 insertions(+), 9 deletions(-)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 80e14c139d40..725622c7e603 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -2376,11 +2376,11 @@ phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
EXPORT_SYMBOL_GPL(iommu_iova_to_phys);
static size_t iommu_pgsize(struct iommu_domain *domain, unsigned long iova,
- phys_addr_t paddr, size_t size)
+ phys_addr_t paddr, size_t size, size_t *count)
{
- unsigned int pgsize_idx;
+ unsigned int pgsize_idx, pgsize_idx_next;
unsigned long pgsizes;
- size_t pgsize;
+ size_t offset, pgsize, pgsize_next;
unsigned long addr_merge = paddr | iova;
/* Page sizes supported by the hardware and small enough for @size */
@@ -2396,7 +2396,36 @@ static size_t iommu_pgsize(struct iommu_domain *domain, unsigned long iova,
/* Pick the biggest page size remaining */
pgsize_idx = __fls(pgsizes);
pgsize = BIT(pgsize_idx);
+ if (!count)
+ return pgsize;
+ /* Find the next biggest support page size, if it exists */
+ pgsizes = domain->pgsize_bitmap & ~GENMASK(pgsize_idx, 0);
+ if (!pgsizes)
+ goto out_set_count;
+
+ pgsize_idx_next = __ffs(pgsizes);
+ pgsize_next = BIT(pgsize_idx_next);
+
+ /*
+ * There's no point trying a bigger page size unless the virtual
+ * and physical addresses are similarly offset within the larger page.
+ */
+ if ((iova ^ paddr) & (pgsize_next - 1))
+ goto out_set_count;
+
+ /* Calculate the offset to the next page size alignment boundary */
+ offset = pgsize_next - (addr_merge & (pgsize_next - 1));
+
+ /*
+ * If size is big enough to accommodate the larger page, reduce
+ * the number of smaller pages.
+ */
+ if (offset + pgsize_next <= size)
+ size = offset;
+
+out_set_count:
+ *count = size >> pgsize_idx;
return pgsize;
}
@@ -2434,7 +2463,7 @@ static int __iommu_map(struct iommu_domain *domain, unsigned long iova,
pr_debug("map: iova 0x%lx pa %pa size 0x%zx\n", iova, &paddr, size);
while (size) {
- size_t pgsize = iommu_pgsize(domain, iova, paddr, size);
+ size_t pgsize = iommu_pgsize(domain, iova, paddr, size, NULL);
pr_debug("mapping: iova 0x%lx pa %pa pgsize 0x%zx\n",
iova, &paddr, pgsize);
@@ -2485,6 +2514,19 @@ int iommu_map_atomic(struct iommu_domain *domain, unsigned long iova,
}
EXPORT_SYMBOL_GPL(iommu_map_atomic);
+static size_t __iommu_unmap_pages(struct iommu_domain *domain,
+ unsigned long iova, size_t size,
+ struct iommu_iotlb_gather *iotlb_gather)
+{
+ const struct iommu_ops *ops = domain->ops;
+ size_t pgsize, count;
+
+ pgsize = iommu_pgsize(domain, iova, iova, size, &count);
+ return ops->unmap_pages ?
+ ops->unmap_pages(domain, iova, pgsize, count, iotlb_gather) :
+ ops->unmap(domain, iova, pgsize, iotlb_gather);
+}
+
static size_t __iommu_unmap(struct iommu_domain *domain,
unsigned long iova, size_t size,
struct iommu_iotlb_gather *iotlb_gather)
@@ -2494,7 +2536,7 @@ static size_t __iommu_unmap(struct iommu_domain *domain,
unsigned long orig_iova = iova;
unsigned int min_pagesz;
- if (unlikely(ops->unmap == NULL ||
+ if (unlikely(!(ops->unmap || ops->unmap_pages) ||
domain->pgsize_bitmap == 0UL))
return 0;
@@ -2522,10 +2564,9 @@ static size_t __iommu_unmap(struct iommu_domain *domain,
* or we hit an area that isn't mapped.
*/
while (unmapped < size) {
- size_t pgsize;
-
- pgsize = iommu_pgsize(domain, iova, iova, size - unmapped);
- unmapped_page = ops->unmap(domain, iova, pgsize, iotlb_gather);
+ unmapped_page = __iommu_unmap_pages(domain, iova,
+ size - unmapped,
+ iotlb_gather);
if (!unmapped_page)
break;