From 3daa9c51651f2631be373840db0f82a8efb1c63d Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 21 Sep 2016 18:37:42 -0400 Subject: [PATCH] fuse_ioctl_copy_user(): don't open-code copy_page_{to,from}_iter() Signed-off-by: Al Viro Signed-off-by: Miklos Szeredi --- fs/fuse/file.c | 30 +++++++----------------------- 1 file changed, 7 insertions(+), 23 deletions(-) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 3988b43c2f5a..4c1db6ce7c48 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -2339,31 +2339,15 @@ static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov, while (iov_iter_count(&ii)) { struct page *page = pages[page_idx++]; - size_t todo = min_t(size_t, PAGE_SIZE, iov_iter_count(&ii)); - void *kaddr; + size_t copied; - kaddr = kmap(page); + if (!to_user) + copied = copy_page_from_iter(page, 0, PAGE_SIZE, &ii); + else + copied = copy_page_to_iter(page, 0, PAGE_SIZE, &ii); - while (todo) { - char __user *uaddr = ii.iov->iov_base + ii.iov_offset; - size_t iov_len = ii.iov->iov_len - ii.iov_offset; - size_t copy = min(todo, iov_len); - size_t left; - - if (!to_user) - left = copy_from_user(kaddr, uaddr, copy); - else - left = copy_to_user(uaddr, kaddr, copy); - - if (unlikely(left)) - return -EFAULT; - - iov_iter_advance(&ii, copy); - todo -= copy; - kaddr += copy; - } - - kunmap(page); + if (unlikely(copied != PAGE_SIZE && iov_iter_count(&ii))) + return -EFAULT; } return 0;