[PATCH 1/5] iova: Move fast alloc size roundup into alloc_iova_fast()

John Garry
2021-09-24T10:07:15Z

It really is a property of the IOVA rcache code that we need to alloc a
power-of-2 size, so relocate the functionality to resize into
alloc_iova_fast(), rather than the callsites.

Signed-off-by: John Garry <john.garry@huawei.com>
---
drivers/iommu/dma-iommu.c | 8 --------
drivers/iommu/iova.c | 9 +++++++++
drivers/vdpa/vdpa_user/iova_domain.c | 8 --------
3 files changed, 9 insertions(+), 16 deletions(-)

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 896bea04c347..a99b3445fef8 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -444,14 +444,6 @@ static dma_addr_t iommu_dma_alloc_iova(struct iommu_domain *domain,

shift = iova_shift(iovad);
iova_len = size >> shift;
- /*
- * Freeing non-power-of-two-sized allocations back into the IOVA caches
- * will come back to bite us badly, so we have to waste a bit of space
- * rounding up anything cacheable to make sure that can't happen. The
- * order of the unadjusted size will still match upon freeing.
- */
- if (iova_len < (1 << (IOVA_RANGE_CACHE_MAX_SIZE - 1)))
- iova_len = roundup_pow_of_two(iova_len);

dma_limit = min_not_zero(dma_limit, dev->bus_dma_limit);

diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index 9e8bc802ac05..ff567cbc42f7 100644
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -497,6 +497,15 @@ alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
unsigned long iova_pfn;
struct iova *new_iova;

+ /*
+ * Freeing non-power-of-two-sized allocations back into the IOVA caches
+ * will come back to bite us badly, so we have to waste a bit of space
+ * rounding up anything cacheable to make sure that can't happen. The
+ * order of the unadjusted size will still match upon freeing.
+ */
+ if (size < (1 << (IOVA_RANGE_CACHE_MAX_SIZE - 1)))
+ size = roundup_pow_of_two(size);
+
iova_pfn = iova_rcache_get(iovad, size, limit_pfn + 1);
if (iova_pfn)
return iova_pfn;
diff --git a/drivers/vdpa/vdpa_user/iova_domain.c b/drivers/vdpa/vdpa_user/iova_domain.c
index 1daae2608860..2b1143f11d8f 100644
--- a/drivers/vdpa/vdpa_user/iova_domain.c
+++ b/drivers/vdpa/vdpa_user/iova_domain.c
@@ -292,14 +292,6 @@ vduse_domain_alloc_iova(struct iova_domain *iovad,
unsigned long iova_len = iova_align(iovad, size) >> shift;
unsigned long iova_pfn;

- /*
- * Freeing non-power-of-two-sized allocations back into the IOVA caches
- * will come back to bite us badly, so we have to waste a bit of space
- * rounding up anything cacheable to make sure that can't happen. The
- * order of the unadjusted size will still match upon freeing.
- */
- if (iova_len < (1 << (IOVA_RANGE_CACHE_MAX_SIZE - 1)))
- iova_len = roundup_pow_of_two(iova_len);
iova_pfn = alloc_iova_fast(iovad, iova_len, limit >> shift, true);

return iova_pfn << shift;
--
2.26.2