On Tue, Aug 16, 2022 at 10:53 AM Vishal Moola (Oracle)
<vishal.moola@xxxxxxxxx> wrote:
>
> Convert to use folios throughout. This is in preparation for the removal of
> find_get_pages_contig(). Now also supports large folios.
>
> Since we may receive more than nr_pages pages, nr_pages may underflow.
> Since nr_pages > 0 is equivalent to index <= end_index, we replaced it
> with this check instead.
>
> Signed-off-by: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
> ---
> fs/btrfs/extent_io.c | 33 +++++++++++++++------------------
> 1 file changed, 15 insertions(+), 18 deletions(-)
>
> diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
> index 8f6b544ae616..f16929bc531b 100644
> --- a/fs/btrfs/extent_io.c
> +++ b/fs/btrfs/extent_io.c
> @@ -1882,9 +1882,8 @@ static int __process_pages_contig(struct address_space *mapping,
> pgoff_t start_index = start >> PAGE_SHIFT;
> pgoff_t end_index = end >> PAGE_SHIFT;
> pgoff_t index = start_index;
> - unsigned long nr_pages = end_index - start_index + 1;
> unsigned long pages_processed = 0;
> - struct page *pages[16];
> + struct folio_batch fbatch;
> int err = 0;
> int i;
>
> @@ -1893,16 +1892,17 @@ static int __process_pages_contig(struct address_space *mapping,
> ASSERT(processed_end && *processed_end == start);
> }
>
> - if ((page_ops & PAGE_SET_ERROR) && nr_pages > 0)
> + if ((page_ops & PAGE_SET_ERROR) && start_index <= end_index)
> mapping_set_error(mapping, -EIO);
>
> - while (nr_pages > 0) {
> - int found_pages;
> + folio_batch_init(&fbatch);
> + while (index <= end_index) {
> + int found_folios;
> +
> + found_folios = filemap_get_folios_contig(mapping, &index,
> + end_index, &fbatch);
>
> - found_pages = find_get_pages_contig(mapping, index,
> - min_t(unsigned long,
> - nr_pages, ARRAY_SIZE(pages)), pages);
> - if (found_pages == 0) {
> + if (found_folios == 0) {
> /*
> * Only if we're going to lock these pages, we can find
> * nothing at @index.
> @@ -1912,23 +1912,20 @@ static int __process_pages_contig(struct address_space *mapping,
> goto out;
> }
>
> - for (i = 0; i < found_pages; i++) {
> + for (i = 0; i < found_folios; i++) {
> int process_ret;
> -
> + struct folio *folio = fbatch.folios[i];
> process_ret = process_one_page(fs_info, mapping,
> - pages[i], locked_page, page_ops,
> + &folio->page, locked_page, page_ops,
> start, end);
> if (process_ret < 0) {
> - for (; i < found_pages; i++)
> - put_page(pages[i]);
> err = -EAGAIN;
> + folio_batch_release(&fbatch);
> goto out;
> }
> - put_page(pages[i]);
> - pages_processed++;
> + pages_processed += folio_nr_pages(folio);
> }
> - nr_pages -= found_pages;
> - index += found_pages;
> + folio_batch_release(&fbatch);
> cond_resched();
> }
> out:
> --
> 2.36.1
>
Just following up on these btrfs patches (2/7, 3/7, 4/7). Does anyone have
time to review them this week? Feedback would be appreciated.
