[PATCH v10 19/69] xen: use vma_lookup() in privcmd_ioctl_mmap()

From: Liam Howlett
Date: Tue Jun 21 2022 - 16:48:08 EST


From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>

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@xxxxxxxxxx
Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Cc: SeongJae Park <sj@xxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
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