Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

[cascardo/linux.git] / fs / fuse / file.c

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 118bcb1..abc66a6 100644 (file)
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -2326,49 +2326,6 @@ static loff_t fuse_file_llseek(struct file *file, loff_t offset, int whence)
        return retval;
 }
 
-static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov,
-                       unsigned int nr_segs, size_t bytes, bool to_user)
-{
-       struct iov_iter ii;
-       int page_idx = 0;
-
-       if (!bytes)
-               return 0;
-
-       iov_iter_init(&ii, to_user ? READ : WRITE, iov, nr_segs, bytes);
-
-       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;
-
-               kaddr = kmap(page);
-
-               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);
-       }
-
-       return 0;
-}
-
 /*
  * CUSE servers compiled on 32bit broke on 64bit kernels because the
  * ABI was defined to be 'struct iovec' which is different on 32bit
@@ -2520,8 +2477,9 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
        struct iovec *iov_page = NULL;
        struct iovec *in_iov = NULL, *out_iov = NULL;
        unsigned int in_iovs = 0, out_iovs = 0, num_pages = 0, max_pages;
-       size_t in_size, out_size, transferred;
-       int err;
+       size_t in_size, out_size, transferred, c;
+       int err, i;
+       struct iov_iter ii;
 
 #if BITS_PER_LONG == 32
        inarg.flags |= FUSE_IOCTL_32BIT;
@@ -2603,10 +2561,13 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
                req->in.args[1].size = in_size;
                req->in.argpages = 1;
 
-               err = fuse_ioctl_copy_user(pages, in_iov, in_iovs, in_size,
-                                          false);
-               if (err)
-                       goto out;
+               err = -EFAULT;
+               iov_iter_init(&ii, WRITE, in_iov, in_iovs, in_size);
+               for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= num_pages); i++) {
+                       c = copy_page_from_iter(pages[i], 0, PAGE_SIZE, &ii);
+                       if (c != PAGE_SIZE && iov_iter_count(&ii))
+                               goto out;
+               }
        }
 
        req->out.numargs = 2;
@@ -2672,7 +2633,14 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
        if (transferred > inarg.out_size)
                goto out;
 
-       err = fuse_ioctl_copy_user(pages, out_iov, out_iovs, transferred, true);
+       err = -EFAULT;
+       iov_iter_init(&ii, READ, out_iov, out_iovs, transferred);
+       for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= num_pages); i++) {
+               c = copy_page_to_iter(pages[i], 0, PAGE_SIZE, &ii);
+               if (c != PAGE_SIZE && iov_iter_count(&ii))
+                       goto out;
+       }
+       err = 0;
  out:
        if (req)
                fuse_put_request(fc, req);