-/*
- * llseek SEEK_DATA or SEEK_HOLE through the page cache.
- */
-static pgoff_t shmem_seek_hole_data(struct address_space *mapping,
- pgoff_t index, pgoff_t end, int whence)
-{
- struct page *page;
- struct pagevec pvec;
- pgoff_t indices[PAGEVEC_SIZE];
- bool done = false;
- int i;
-
- pagevec_init(&pvec);
- pvec.nr = 1; /* start small: we may be there already */
- while (!done) {
- pvec.nr = find_get_entries(mapping, index,
- pvec.nr, pvec.pages, indices);
- if (!pvec.nr) {
- if (whence == SEEK_DATA)
- index = end;
- break;
- }
- for (i = 0; i < pvec.nr; i++, index++) {
- if (index < indices[i]) {
- if (whence == SEEK_HOLE) {
- done = true;
- break;
- }
- index = indices[i];
- }
- page = pvec.pages[i];
- if (page && !xa_is_value(page)) {
- if (!PageUptodate(page))
- page = NULL;
- }
- if (index >= end ||
- (page && whence == SEEK_DATA) ||
- (!page && whence == SEEK_HOLE)) {
- done = true;
- break;
- }
- }
- pagevec_remove_exceptionals(&pvec);
- pagevec_release(&pvec);
- pvec.nr = PAGEVEC_SIZE;
- cond_resched();
- }
- return index;
-}
-