pvfs_bufmap_copy_from_iovec(): don't rely upon size being equal to iov_iter_count...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

diff --git a/fs/orangefs/pvfs2-bufmap.c b/fs/orangefs/pvfs2-bufmap.c
index 8438830..dacf42b 100644 (file)
--- a/fs/orangefs/pvfs2-bufmap.c
+++ b/fs/orangefs/pvfs2-bufmap.c
@@ -512,26 +512,25 @@ int pvfs_bufmap_copy_from_iovec(struct pvfs2_bufmap *bufmap,
                                int buffer_index,
                                size_t size)
 {
-       struct pvfs_bufmap_desc *to;
-       struct page *page;
-       size_t copied;
+       struct pvfs_bufmap_desc *to = &bufmap->desc_array[buffer_index];
        int i;
 
        gossip_debug(GOSSIP_BUFMAP_DEBUG,
-                    "%s: buffer_index:%d: size:%lu:\n",
+                    "%s: buffer_index:%d: size:%zu:\n",
                     __func__, buffer_index, size);
 
-       to = &bufmap->desc_array[buffer_index];
 
        for (i = 0; size; i++) {
-               page = to->page_array[i];
-               copied = copy_page_from_iter(page, 0, PAGE_SIZE, iter);
-               size -= copied;
-               if ((copied == 0) && (size))
-                       break;
+               struct page *page = to->page_array[i];
+               size_t n = size;
+               if (n > PAGE_SIZE)
+                       n = PAGE_SIZE;
+               n = copy_page_from_iter(page, 0, n, iter);
+               if (!n)
+                       return -EFAULT;
+               size -= n;
        }
-
-       return size ? -EFAULT : 0;
+       return 0;
 
 }