[PATCH 19/34] fsl_hypervisor: convert put_page() to put_user_page*()

From: john . hubbard
Date: Thu Aug 01 2019 - 22:24:33 EST

From: John Hubbard <jhubbard@xxxxxxxxxx>

For pages that were retained via get_user_pages*(), release those pages
via the new put_user_page*() routines, instead of via put_page() or

This is part a tree-wide conversion, as described in commit fc1d8e7cca2d
("mm: introduce put_user_page*(), placeholder versions").

This changes the release code slightly, because each page slot in the
page_list[] array is no longer checked for NULL. However, that check
was wrong anyway, because the get_user_pages() pattern of usage here
never allowed for NULL entries within a range of pinned pages.

Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
drivers/virt/fsl_hypervisor.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/virt/fsl_hypervisor.c b/drivers/virt/fsl_hypervisor.c
index 93d5bebf9572..a8f78d572c45 100644
--- a/drivers/virt/fsl_hypervisor.c
+++ b/drivers/virt/fsl_hypervisor.c
@@ -292,11 +292,8 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy __user *p)
virt_to_phys(sg_list), num_pages);

- if (pages) {
- for (i = 0; i < num_pages; i++)
- if (pages[i])
- put_page(pages[i]);
- }
+ if (pages)
+ put_user_pages(pages, num_pages);