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path: root/drivers/vfio
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Diffstat (limited to 'drivers/vfio')
-rw-r--r--drivers/vfio/vfio_iommu_type1.c32
1 files changed, 24 insertions, 8 deletions
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 34d17e51dc97..52af5fc01d91 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -230,20 +230,36 @@ static int put_pfn(unsigned long pfn, int prot)
return 0;
}
-static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
+static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr,
+ int prot, unsigned long *pfn)
{
struct page *page[1];
struct vm_area_struct *vma;
- int ret = -EFAULT;
+ int ret;
+
+ if (mm == current->mm) {
+ ret = get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE),
+ page);
+ } else {
+ unsigned int flags = 0;
+
+ if (prot & IOMMU_WRITE)
+ flags |= FOLL_WRITE;
+
+ down_read(&mm->mmap_sem);
+ ret = get_user_pages_remote(NULL, mm, vaddr, 1, flags, page,
+ NULL);
+ up_read(&mm->mmap_sem);
+ }
- if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
+ if (ret == 1) {
*pfn = page_to_pfn(page[0]);
return 0;
}
- down_read(&current->mm->mmap_sem);
+ down_read(&mm->mmap_sem);
- vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);
+ vma = find_vma_intersection(mm, vaddr, vaddr + 1);
if (vma && vma->vm_flags & VM_PFNMAP) {
*pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
@@ -251,7 +267,7 @@ static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
ret = 0;
}
- up_read(&current->mm->mmap_sem);
+ up_read(&mm->mmap_sem);
return ret;
}
@@ -272,7 +288,7 @@ static long vfio_pin_pages_remote(unsigned long vaddr, long npage,
if (!current->mm)
return -ENODEV;
- ret = vaddr_get_pfn(vaddr, prot, pfn_base);
+ ret = vaddr_get_pfn(current->mm, vaddr, prot, pfn_base);
if (ret)
return ret;
@@ -295,7 +311,7 @@ static long vfio_pin_pages_remote(unsigned long vaddr, long npage,
for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) {
unsigned long pfn = 0;
- ret = vaddr_get_pfn(vaddr, prot, &pfn);
+ ret = vaddr_get_pfn(current->mm, vaddr, prot, &pfn);
if (ret)
break;