> * Bulk filling of pages can take multiple calls. Not filling the entire
> @@ -426,7 +484,7 @@ _xfs_buf_map_folios(
> {
> ASSERT(bp->b_flags & _XBF_FOLIOS);
> if (bp->b_folio_count == 1) {
> - /* A single page buffer is always mappable */
> + /* A single folio buffer is always mappable */
> bp->b_addr = folio_address(bp->b_folios[0]);
> } else if (flags & XBF_UNMAPPED) {
> bp->b_addr = NULL;
> @@ -1525,20 +1583,28 @@ xfs_buf_ioapply_map(
> int *count,
> blk_opf_t op)
> {
> - int page_index;
> - unsigned int total_nr_pages = bp->b_folio_count;
> - int nr_pages;
> + int folio_index;
> + unsigned int total_nr_folios = bp->b_folio_count;
> + int nr_folios;
> struct bio *bio;
> sector_t sector = bp->b_maps[map].bm_bn;
> int size;
> int offset;
>
> - /* skip the pages in the buffer before the start offset */
> - page_index = 0;
> + /*
> + * If the start offset if larger than a single page, we need to be
> + * careful. We might have a high order folio, in which case the indexing
> + * is from the start of the buffer. However, if we have more than one
> + * folio single page folio in the buffer, we need to skip the folios in
s/folio single page folio/single page folio/
> + * the buffer before the start offset.
> + */
> + folio_index = 0;
> offset = *buf_offset;
> - while (offset >= PAGE_SIZE) {
> - page_index++;
> - offset -= PAGE_SIZE;
> + if (bp->b_folio_count > 1) {
> + while (offset >= PAGE_SIZE) {
> + folio_index++;
> + offset -= PAGE_SIZE;
Can this be:
folio_index = offset >> PAGE_SHIFT;
offset = offset_in_page(offset);
instead of a loop?
> + }
> }
>
> /*
--
Pankaj
