On Tue, Aug 16, 2022 at 10:52:42AM -0700, Vishal Moola (Oracle) wrote:
> Converted function 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.
>
> Also this function does not care about the pages being contiguous so we
> can just use filemap_get_folios() to be more efficient.
>
> Signed-off-by: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
With minor comments
Acked-by: David Sterba <dsterba@xxxxxxxx>
> --- a/fs/btrfs/compression.c
> +++ b/fs/btrfs/compression.c
> @@ -8,6 +8,7 @@
> #include <linux/file.h>
> #include <linux/fs.h>
> #include <linux/pagemap.h>
> +#include <linux/pagevec.h>
> #include <linux/highmem.h>
> #include <linux/kthread.h>
> #include <linux/time.h>
> @@ -339,8 +340,7 @@ static noinline void end_compressed_writeback(struct inode *inode,
> struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
> unsigned long index = cb->start >> PAGE_SHIFT;
> unsigned long end_index = (cb->start + cb->len - 1) >> PAGE_SHIFT;
> - struct page *pages[16];
> - unsigned long nr_pages = end_index - index + 1;
> + struct folio_batch fbatch;
> const int errno = blk_status_to_errno(cb->status);
> int i;
> int ret;
> @@ -348,24 +348,22 @@ static noinline void end_compressed_writeback(struct inode *inode,
> if (errno)
> mapping_set_error(inode->i_mapping, errno);
>
> - while (nr_pages > 0) {
> - ret = find_get_pages_contig(inode->i_mapping, index,
> - min_t(unsigned long,
> - nr_pages, ARRAY_SIZE(pages)), pages);
> + folio_batch_init(&fbatch);
> + while (index <= end_index) {
> + ret = filemap_get_folios(inode->i_mapping, &index, end_index,
> + &fbatch);
> +
> if (ret == 0) {
> - nr_pages -= 1;
> - index += 1;
> - continue;
> + return;
> }
Please drop { } around single statement
> for (i = 0; i < ret; i++) {
> + struct folio *folio = fbatch.folios[i];
And add a newline after declaration.
> if (errno)
> - SetPageError(pages[i]);
> - btrfs_page_clamp_clear_writeback(fs_info, pages[i],
> + folio_set_error(folio);
> + btrfs_page_clamp_clear_writeback(fs_info, &folio->page,
> cb->start, cb->len);
> - put_page(pages[i]);
> }
> - nr_pages -= ret;
> - index += ret;
> + folio_batch_release(&fbatch);
> }
> /* the inode may be gone now */
> }
> --
> 2.36.1
