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| author | Niklas Schnelle <schnelle@linux.ibm.com> | 2023-08-25 13:02:38 +0200 |
|---|---|---|
| committer | Niklas Schnelle <schnelle@linux.ibm.com> | 2023-11-20 15:50:31 +0100 |
| commit | dd6c652029bbf586fb7dba080d35e8fd8f6ed612 (patch) | |
| tree | 62e499717a9319a40f215a030768ca053c3f0143 | |
| parent | 03ca797a392cf8eaede525feb8983d8eaf1bc517 (diff) | |
| download | linux-b4/viommu-deferred-flush.tar.gz | |
iommu/virtio: Add ops->flush_iotlb_all and enable deferred flushb4/viommu-deferred-flush
Add ops->flush_iotlb_all operation to enable virtio-iommu for the
dma-iommu deferred flush scheme. This results in a significant increase
in performance in exchange for a window in which devices can still
access previously IOMMU mapped memory when running with
CONFIG_IOMMU_DEFAULT_DMA_LAZY. The previous strict behavior can be
achieved with iommu.strict=1 on the kernel command line or
CONFIG_IOMMU_DEFAULT_DMA_STRICT.
Link: https://lore.kernel.org/lkml/20230802123612.GA6142@myrica/
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
| -rw-r--r-- | drivers/iommu/virtio-iommu.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c index 3f18f69d70d896..ef6a8744510594 100644 --- a/drivers/iommu/virtio-iommu.c +++ b/drivers/iommu/virtio-iommu.c @@ -926,6 +926,19 @@ static int viommu_iotlb_sync_map(struct iommu_domain *domain, return viommu_sync_req(vdomain->viommu); } +static void viommu_flush_iotlb_all(struct iommu_domain *domain) +{ + struct viommu_domain *vdomain = to_viommu_domain(domain); + + /* + * May be called before the viommu is initialized including + * while creating direct mapping + */ + if (!vdomain->nr_endpoints) + return; + viommu_sync_req(vdomain->viommu); +} + static void viommu_get_resv_regions(struct device *dev, struct list_head *head) { struct iommu_resv_region *entry, *new_entry, *msi = NULL; @@ -1051,6 +1064,8 @@ static bool viommu_capable(struct device *dev, enum iommu_cap cap) switch (cap) { case IOMMU_CAP_CACHE_COHERENCY: return true; + case IOMMU_CAP_DEFERRED_FLUSH: + return true; default: return false; } @@ -1071,6 +1086,7 @@ static struct iommu_ops viommu_ops = { .map_pages = viommu_map_pages, .unmap_pages = viommu_unmap_pages, .iova_to_phys = viommu_iova_to_phys, + .flush_iotlb_all = viommu_flush_iotlb_all, .iotlb_sync = viommu_iotlb_sync, .iotlb_sync_map = viommu_iotlb_sync_map, .free = viommu_domain_free, |