@@ -327,9 +327,8 @@ static int put_pfn(unsigned long pfn, int prot)
{
if (!is_invalid_reserved_pfn(pfn)) {
struct page *page = pfn_to_page(pfn);
- if (prot & IOMMU_WRITE)
- SetPageDirty(page);
- put_page(page);
+
+ put_user_pages_dirty_lock(&page, 1, prot & IOMMU_WRITE);
return 1;
}
return 0;
@@ -347,8 +346,8 @@ static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr,
flags |= FOLL_WRITE;
down_read(&mm->mmap_sem);
- ret = get_user_pages_remote(NULL, mm, vaddr, 1, flags | FOLL_LONGTERM,
- page, NULL, NULL);
+ ret = pin_longterm_pages_remote(NULL, mm, vaddr, 1, flags, page, NULL,
+ NULL);
if (ret == 1) {
*pfn = page_to_pfn(page[0]);
return 0;
1. Change vfio from get_user_pages(FOLL_LONGTERM), to pin_longterm_pages(), which sets both FOLL_LONGTERM and FOLL_PIN. 2. Because all FOLL_PIN-acquired pages must be released via put_user_page(), also convert the put_page() call over to put_user_pages(). Note that this effectively changes the code's behavior in vfio_iommu_type1.c: put_pfn(): it now ultimately calls set_page_dirty_lock(), instead of set_page_dirty(). This is probably more accurate. As Christoph Hellwig put it, "set_page_dirty() is only safe if we are dealing with a file backed page where we have reference on the inode it hangs off." [1] [1] https://lore.kernel.org/r/20190723153640.GB720@lst.de Cc: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> --- drivers/vfio/vfio_iommu_type1.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)