iommu/dma: Handle MSI mappings separately

MSI pages must always be mapped into a device's *current* domain, which
*might* be the default DMA domain, but might instead be a VFIO domain
with its own MSI cookie. This subtlety got accidentally lost in the
streamlining of __iommu_dma_map(), but rather than reintroduce more
complexity and/or special-casing, it turns out neater to just split this
path out entirely.

Since iommu_dma_get_msi_page() already duplicates much of what
__iommu_dma_map() does, it can easily just make the allocation and
mapping calls directly as well. That way we can further streamline the
helper back to exclusively operating on DMA domains.

Fixes: b61d271e59 ("iommu/dma: Move domain lookup into __iommu_dma_{map,unmap}")
Reported-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reported-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Robin Murphy 2019-07-29 16:32:38 +01:00 committed by Joerg Roedel
parent e21a712a96
commit 8af23fad62
1 changed files with 10 additions and 7 deletions

View File

@ -459,13 +459,11 @@ static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys,
{
struct iommu_domain *domain = iommu_get_dma_domain(dev);
struct iommu_dma_cookie *cookie = domain->iova_cookie;
size_t iova_off = 0;
struct iova_domain *iovad = &cookie->iovad;
size_t iova_off = iova_offset(iovad, phys);
dma_addr_t iova;
if (cookie->type == IOMMU_DMA_IOVA_COOKIE) {
iova_off = iova_offset(&cookie->iovad, phys);
size = iova_align(&cookie->iovad, size + iova_off);
}
size = iova_align(iovad, size + iova_off);
iova = iommu_dma_alloc_iova(domain, size, dma_get_mask(dev), dev);
if (!iova)
@ -1147,16 +1145,21 @@ static struct iommu_dma_msi_page *iommu_dma_get_msi_page(struct device *dev,
if (!msi_page)
return NULL;
iova = __iommu_dma_map(dev, msi_addr, size, prot);
if (iova == DMA_MAPPING_ERROR)
iova = iommu_dma_alloc_iova(domain, size, dma_get_mask(dev), dev);
if (!iova)
goto out_free_page;
if (iommu_map(domain, iova, msi_addr, size, prot))
goto out_free_iova;
INIT_LIST_HEAD(&msi_page->list);
msi_page->phys = msi_addr;
msi_page->iova = iova;
list_add(&msi_page->list, &cookie->msi_page_list);
return msi_page;
out_free_iova:
iommu_dma_free_iova(cookie, iova, size);
out_free_page:
kfree(msi_page);
return NULL;