From c0c763598960153e10622ff0a802012a073174a0 Mon Sep 17 00:00:00 2001 From: Jean-Philippe Brucker Date: Wed, 1 Dec 2021 17:33:24 +0000 Subject: [PATCH] iommu/virtio: Pass end address to viommu_add_mapping() To support identity mappings, the virtio-iommu driver must be able to represent full 64-bit ranges internally. Pass (start, end) instead of (start, size) to viommu_add/del_mapping(). Clean comments. The one about the returned size was never true: when sweeping the whole address space the returned size will most certainly be smaller than 2^64. Reviewed-by: Eric Auger Reviewed-by: Kevin Tian Signed-off-by: Jean-Philippe Brucker Link: https://lore.kernel.org/r/20211201173323.1045819-5-jean-philippe@linaro.org Signed-off-by: Joerg Roedel --- drivers/iommu/virtio-iommu.c | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c index 1b3c1f2..2fa370c 100644 --- a/drivers/iommu/virtio-iommu.c +++ b/drivers/iommu/virtio-iommu.c @@ -311,8 +311,8 @@ out_unlock: * * On success, return the new mapping. Otherwise return NULL. */ -static int viommu_add_mapping(struct viommu_domain *vdomain, unsigned long iova, - phys_addr_t paddr, size_t size, u32 flags) +static int viommu_add_mapping(struct viommu_domain *vdomain, u64 iova, u64 end, + phys_addr_t paddr, u32 flags) { unsigned long irqflags; struct viommu_mapping *mapping; @@ -323,7 +323,7 @@ static int viommu_add_mapping(struct viommu_domain *vdomain, unsigned long iova, mapping->paddr = paddr; mapping->iova.start = iova; - mapping->iova.last = iova + size - 1; + mapping->iova.last = end; mapping->flags = flags; spin_lock_irqsave(&vdomain->mappings_lock, irqflags); @@ -338,26 +338,24 @@ static int viommu_add_mapping(struct viommu_domain *vdomain, unsigned long iova, * * @vdomain: the domain * @iova: start of the range - * @size: size of the range. A size of 0 corresponds to the entire address - * space. + * @end: end of the range * - * On success, returns the number of unmapped bytes (>= size) + * On success, returns the number of unmapped bytes */ static size_t viommu_del_mappings(struct viommu_domain *vdomain, - unsigned long iova, size_t size) + u64 iova, u64 end) { size_t unmapped = 0; unsigned long flags; - unsigned long last = iova + size - 1; struct viommu_mapping *mapping = NULL; struct interval_tree_node *node, *next; spin_lock_irqsave(&vdomain->mappings_lock, flags); - next = interval_tree_iter_first(&vdomain->mappings, iova, last); + next = interval_tree_iter_first(&vdomain->mappings, iova, end); while (next) { node = next; mapping = container_of(node, struct viommu_mapping, iova); - next = interval_tree_iter_next(node, iova, last); + next = interval_tree_iter_next(node, iova, end); /* Trying to split a mapping? */ if (mapping->iova.start < iova) @@ -656,8 +654,8 @@ static void viommu_domain_free(struct iommu_domain *domain) { struct viommu_domain *vdomain = to_viommu_domain(domain); - /* Free all remaining mappings (size 2^64) */ - viommu_del_mappings(vdomain, 0, 0); + /* Free all remaining mappings */ + viommu_del_mappings(vdomain, 0, ULLONG_MAX); if (vdomain->viommu) ida_free(&vdomain->viommu->domain_ids, vdomain->id); @@ -742,6 +740,7 @@ static int viommu_map(struct iommu_domain *domain, unsigned long iova, { int ret; u32 flags; + u64 end = iova + size - 1; struct virtio_iommu_req_map map; struct viommu_domain *vdomain = to_viommu_domain(domain); @@ -752,7 +751,7 @@ static int viommu_map(struct iommu_domain *domain, unsigned long iova, if (flags & ~vdomain->map_flags) return -EINVAL; - ret = viommu_add_mapping(vdomain, iova, paddr, size, flags); + ret = viommu_add_mapping(vdomain, iova, end, paddr, flags); if (ret) return ret; @@ -761,7 +760,7 @@ static int viommu_map(struct iommu_domain *domain, unsigned long iova, .domain = cpu_to_le32(vdomain->id), .virt_start = cpu_to_le64(iova), .phys_start = cpu_to_le64(paddr), - .virt_end = cpu_to_le64(iova + size - 1), + .virt_end = cpu_to_le64(end), .flags = cpu_to_le32(flags), }; @@ -770,7 +769,7 @@ static int viommu_map(struct iommu_domain *domain, unsigned long iova, ret = viommu_send_req_sync(vdomain->viommu, &map, sizeof(map)); if (ret) - viommu_del_mappings(vdomain, iova, size); + viommu_del_mappings(vdomain, iova, end); return ret; } @@ -783,7 +782,7 @@ static size_t viommu_unmap(struct iommu_domain *domain, unsigned long iova, struct virtio_iommu_req_unmap unmap; struct viommu_domain *vdomain = to_viommu_domain(domain); - unmapped = viommu_del_mappings(vdomain, iova, size); + unmapped = viommu_del_mappings(vdomain, iova, iova + size - 1); if (unmapped < size) return 0; -- 2.7.4