From: Daniel Jordan daniel.m.jordan@oracle.com
[ Upstream commit be16c1fd99f41abebc0bf965d5d29cd18c9d271e ]
vaddr_get_pfn() simply returns 0 on success. Have it report the number of pfns successfully gotten instead, whether from page pinning or follow_fault_pfn(), which will be used later when batching pinning.
Change the last check in vfio_pin_pages_remote() for consistency with the other two.
Signed-off-by: Daniel Jordan daniel.m.jordan@oracle.com Signed-off-by: Alex Williamson alex.williamson@redhat.com Stable-dep-of: 873aefb376bb ("vfio/type1: Unpin zero pages") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/vfio/vfio_iommu_type1.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index fbd438e9b9b0..2d26244f9c32 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -464,6 +464,10 @@ static int follow_fault_pfn(struct vm_area_struct *vma, struct mm_struct *mm, return ret; }
+/* + * Returns the positive number of pfns successfully obtained or a negative + * error code. + */ static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr, int prot, unsigned long *pfn) { @@ -480,7 +484,6 @@ static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr, page, NULL, NULL); if (ret == 1) { *pfn = page_to_pfn(page[0]); - ret = 0; goto done; }
@@ -494,8 +497,12 @@ static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr, if (ret == -EAGAIN) goto retry;
- if (!ret && !is_invalid_reserved_pfn(*pfn)) - ret = -EFAULT; + if (!ret) { + if (is_invalid_reserved_pfn(*pfn)) + ret = 1; + else + ret = -EFAULT; + } } done: mmap_read_unlock(mm); @@ -521,7 +528,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr, return -ENODEV;
ret = vaddr_get_pfn(current->mm, vaddr, dma->prot, pfn_base); - if (ret) + if (ret < 0) return ret;
pinned++; @@ -548,7 +555,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr, for (vaddr += PAGE_SIZE, iova += PAGE_SIZE; pinned < npage; pinned++, vaddr += PAGE_SIZE, iova += PAGE_SIZE) { ret = vaddr_get_pfn(current->mm, vaddr, dma->prot, &pfn); - if (ret) + if (ret < 0) break;
if (pfn != *pfn_base + pinned || @@ -574,7 +581,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr, ret = vfio_lock_acct(dma, lock_acct, false);
unpin_out: - if (ret) { + if (ret < 0) { if (!rsvd) { for (pfn = *pfn_base ; pinned ; pfn++, pinned--) put_pfn(pfn, dma->prot); @@ -618,7 +625,7 @@ static int vfio_pin_page_external(struct vfio_dma *dma, unsigned long vaddr, return -ENODEV;
ret = vaddr_get_pfn(mm, vaddr, dma->prot, pfn_base); - if (!ret && do_accounting && !is_invalid_reserved_pfn(*pfn_base)) { + if (ret == 1 && do_accounting && !is_invalid_reserved_pfn(*pfn_base)) { ret = vfio_lock_acct(dma, 1, true); if (ret) { put_pfn(*pfn_base, dma->prot);