[PATCH v12 19/69] xen: use vma_lookup() in privcmd_ioctl_mmap()

Liam Howlett
2022-07-20T02:19:12Z

vma_lookup() walks the VMA tree for a specific value, find_vma() will
search the tree after walking to a specific value. It is more efficient
to only walk to the requested value since privcmd_ioctl_mmap() will exit
the loop if vm_start != msg->va.

Link: https://lkml.kernel.org/r/20220504011345.662299-4-Liam.Howlett@oracle.com
Link: https://lkml.kernel.org/r/20220621204632.3370049-20-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: SeongJae Park <sj@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
drivers/xen/privcmd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index 3369734108af..ad17166b0ef6 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -282,7 +282,7 @@ static long privcmd_ioctl_mmap(struct file *file, void __user *udata)
struct page, lru);
struct privcmd_mmap_entry *msg = page_address(page);

- vma = find_vma(mm, msg->va);
+ vma = vma_lookup(mm, msg->va);
rc = -EINVAL;

if (!vma || (msg->va != vma->vm_start) || vma->vm_private_data)
--
2.35.1