fs-verity: use kmap_local_page() instead of kmap()

Convert the use of kmap() to its recommended replacement
kmap_local_page().  This avoids the overhead of doing a non-local
mapping, which is unnecessary in this case.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Link: https://lore.kernel.org/r/20220818224010.43778-1-ebiggers@kernel.org

diff --git a/fs/verity/read_metadata.c b/fs/verity/read_metadata.c
index 6ee849dc7bc183c0f55212cb5a5639fe2d134e19..2aefc5565152ad15e3abc46fe8b0cc9045faccaa 100644 (file)
--- a/fs/verity/read_metadata.c
+++ b/fs/verity/read_metadata.c
@@ -53,14 +53,14 @@ static int fsverity_read_merkle_tree(struct inode *inode,
                        break;
                }
 
-               virt = kmap(page);
+               virt = kmap_local_page(page);
                if (copy_to_user(buf, virt + offs_in_page, bytes_to_copy)) {
-                       kunmap(page);
+                       kunmap_local(virt);
                        put_page(page);
                        err = -EFAULT;
                        break;
                }
-               kunmap(page);
+               kunmap_local(virt);
                put_page(page);
 
                retval += bytes_to_copy;