> diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
> index bcc6e0e5334e..626c3c8399cc 100644
> --- a/fs/iomap/buffered-io.c
> +++ b/fs/iomap/buffered-io.c
> @@ -20,6 +20,8 @@ struct iomap_folio_state {
> spinlock_t state_lock;
> unsigned int read_bytes_pending;
> atomic_t write_bytes_pending;
> + /* number of pages being currently written back */
> + unsigned nr_pages_writeback;
This adds more sizse to the folio state. Shouldn't this be the same
as
DIV_ROUND_UP(write_bytes_pending, PAGE_SIZE)
anyway?
> + unsigned end_blk = min((unsigned)(i_size_read(inode) >> inode->i_blkbits),
> + i_blocks_per_folio(inode, folio));
Overly long line. Also not sure why the cast is needed to start with?
> + unsigned nblks = 0;
> +
> + while (start_blk < end_blk) {
> + if (ifs_block_is_dirty(folio, ifs, start_blk))
> + nblks++;
> + start_blk++;
> + }
We have this pattern open coded in a few places. Maybe factor it into a
helper first? And then maybe someone smart can actually make it use
find_first_bit/find_next_bit.
> +static bool iomap_granular_dirty_pages(struct folio *folio)
> +{
> + struct iomap_folio_state *ifs = folio->private;
> + struct inode *inode;
> + unsigned block_size;
> +
> + if (!ifs)
> + return false;
> +
> + inode = folio->mapping->host;
> + block_size = 1 << inode->i_blkbits;
> +
> + if (block_size >= PAGE_SIZE) {
> + WARN_ON(block_size & (PAGE_SIZE - 1));
> + return true;
> + }
> + return false;
Do we need the WARN_ON? Both the block and page size must be powers
of two, so I can't see how it would trigger. Also this can use the
i_blocksize helper.
I.e. just turn this into:
return i_blocksize(folio->mapping->host) >= PAGE_SIZE;
> +static bool iomap_dirty_folio_range(struct address_space *mapping, struct folio *folio,
Overly long line.
> + wpc->wbc->no_stats_accounting = true;
Who does the writeback accounting now? Maybe throw in a comment if
iomap is now doing something different than all the other writeback
code.
