[PATCH 03/13] vfio/type1: Use sychronized interface of the IOMMU-API

From: Joerg Roedel
Date: Thu Aug 17 2017 - 09:01:57 EST


From: Joerg Roedel <jroedel@xxxxxxx>

The map and unmap functions of the IOMMU-API changed their
semantics: They do no longer guarantee that the hardware
TLBs are synchronized with the page-table updates they made.

To make conversion easier, new synchronized functions have
been introduced which give these guarantees again until the
code is converted to use the new TLB-flush interface of the
IOMMU-API, which allows certain optimizations.

But for now, just convert this code to use the synchronized
functions so that it will behave as before.

Cc: Alex Williamson <alex.williamson@xxxxxxxxxx>
Cc: kvm@xxxxxxxxxxxxxxx
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
---
drivers/vfio/vfio_iommu_type1.c | 38 ++++++++++++++++++++------------------
1 file changed, 20 insertions(+), 18 deletions(-)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 8549cb1..4ad83d4 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -672,7 +672,7 @@ static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
struct vfio_domain, next);

list_for_each_entry_continue(d, &iommu->domain_list, next) {
- iommu_unmap(d->domain, dma->iova, dma->size);
+ iommu_unmap_sync(d->domain, dma->iova, dma->size);
cond_resched();
}

@@ -687,9 +687,9 @@ static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
}

/*
- * To optimize for fewer iommu_unmap() calls, each of which
- * may require hardware cache flushing, try to find the
- * largest contiguous physical memory chunk to unmap.
+ * To optimize for fewer iommu_unmap_sync() calls, each of which
+ * may require hardware cache flushing, try to find the largest
+ * contiguous physical memory chunk to unmap.
*/
for (len = PAGE_SIZE;
!domain->fgsp && iova + len < end; len += PAGE_SIZE) {
@@ -698,7 +698,7 @@ static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
break;
}

- unmapped = iommu_unmap(domain->domain, iova, len);
+ unmapped = iommu_unmap_sync(domain->domain, iova, len);
if (WARN_ON(!unmapped))
break;

@@ -877,15 +877,15 @@ static int map_try_harder(struct vfio_domain *domain, dma_addr_t iova,
int ret = 0;

for (i = 0; i < npage; i++, pfn++, iova += PAGE_SIZE) {
- ret = iommu_map(domain->domain, iova,
- (phys_addr_t)pfn << PAGE_SHIFT,
- PAGE_SIZE, prot | domain->prot);
+ ret = iommu_map_sync(domain->domain, iova,
+ (phys_addr_t)pfn << PAGE_SHIFT,
+ PAGE_SIZE, prot | domain->prot);
if (ret)
break;
}

for (; i < npage && i > 0; i--, iova -= PAGE_SIZE)
- iommu_unmap(domain->domain, iova, PAGE_SIZE);
+ iommu_unmap_sync(domain->domain, iova, PAGE_SIZE);

return ret;
}
@@ -897,8 +897,9 @@ static int vfio_iommu_map(struct vfio_iommu *iommu, dma_addr_t iova,
int ret;

list_for_each_entry(d, &iommu->domain_list, next) {
- ret = iommu_map(d->domain, iova, (phys_addr_t)pfn << PAGE_SHIFT,
- npage << PAGE_SHIFT, prot | d->prot);
+ ret = iommu_map_sync(d->domain, iova,
+ (phys_addr_t)pfn << PAGE_SHIFT,
+ npage << PAGE_SHIFT, prot | d->prot);
if (ret) {
if (ret != -EBUSY ||
map_try_harder(d, iova, pfn, npage, prot))
@@ -912,7 +913,7 @@ static int vfio_iommu_map(struct vfio_iommu *iommu, dma_addr_t iova,

unwind:
list_for_each_entry_continue_reverse(d, &iommu->domain_list, next)
- iommu_unmap(d->domain, iova, npage << PAGE_SHIFT);
+ iommu_unmap_sync(d->domain, iova, npage << PAGE_SHIFT);

return ret;
}
@@ -1102,8 +1103,8 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
size = npage << PAGE_SHIFT;
}

- ret = iommu_map(domain->domain, iova, phys,
- size, dma->prot | domain->prot);
+ ret = iommu_map_sync(domain->domain, iova, phys,
+ size, dma->prot | domain->prot);
if (ret)
return ret;

@@ -1133,13 +1134,14 @@ static void vfio_test_domain_fgsp(struct vfio_domain *domain)
if (!pages)
return;

- ret = iommu_map(domain->domain, 0, page_to_phys(pages), PAGE_SIZE * 2,
- IOMMU_READ | IOMMU_WRITE | domain->prot);
+ ret = iommu_map_sync(domain->domain, 0, page_to_phys(pages),
+ PAGE_SIZE * 2,
+ IOMMU_READ | IOMMU_WRITE | domain->prot);
if (!ret) {
- size_t unmapped = iommu_unmap(domain->domain, 0, PAGE_SIZE);
+ size_t unmapped = iommu_unmap_sync(domain->domain, 0, PAGE_SIZE);

if (unmapped == PAGE_SIZE)
- iommu_unmap(domain->domain, PAGE_SIZE, PAGE_SIZE);
+ iommu_unmap_sync(domain->domain, PAGE_SIZE, PAGE_SIZE);
else
domain->fgsp = true;
}
--
2.7.4