tmpfs: add support for read_iter and write_iter

[karo-tx-linux.git] / mm / filemap.c

diff --git a/mm/filemap.c b/mm/filemap.c
index 1ac1ceeb4d9a064464e3872f87cc2de786b537f1..9b0b85223d5c2b261399be95b9a38e0370bd4428 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1315,44 +1315,6 @@ out:
        file_accessed(filp);
 }
 
-int file_read_actor(read_descriptor_t *desc, struct page *page,
-                       unsigned long offset, unsigned long size)
-{
-       char *kaddr;
-       unsigned long left, count = desc->count;
-
-       if (size > count)
-               size = count;
-
-       /*
-        * Faults on the destination of a read are common, so do it before
-        * taking the kmap.
-        */
-       if (!fault_in_pages_writeable(desc->arg.buf, size)) {
-               kaddr = kmap_atomic(page);
-               left = __copy_to_user_inatomic(desc->arg.buf,
-                                               kaddr + offset, size);
-               kunmap_atomic(kaddr);
-               if (left == 0)
-                       goto success;
-       }
-
-       /* Do it the slow way */
-       kaddr = kmap(page);
-       left = __copy_to_user(desc->arg.buf, kaddr + offset, size);
-       kunmap(page);
-
-       if (left) {
-               size -= left;
-               desc->error = -EFAULT;
-       }
-success:
-       desc->count = count - size;
-       desc->written += size;
-       desc->arg.buf += size;
-       return size;
-}
-
 /*
  * Performs necessary checks before doing a write
  * @iov:       io vector request
@@ -1392,8 +1354,8 @@ int generic_segment_checks(const struct iovec *iov,
 }
 EXPORT_SYMBOL(generic_segment_checks);
 
-static int file_read_iter_actor(read_descriptor_t *desc, struct page *page,
-                               unsigned long offset, unsigned long size)
+int file_read_iter_actor(read_descriptor_t *desc, struct page *page,
+                        unsigned long offset, unsigned long size)
 {
        struct iov_iter *iter = desc->arg.data;
        unsigned long copied = 0;