diff options
Diffstat (limited to 'drivers/iommu/iova.c')
| -rw-r--r-- | drivers/iommu/iova.c | 9 |
1 files changed, 9 insertions, 0 deletions
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; |