Unverified Commit d9dc477f authored by Brian Foster's avatar Brian Foster Committed by Christian Brauner
Browse files

iomap: advance the iter directly on buffered read 



iomap buffered read advances the iter via iter.processed. To
continue separating iter advance from return status, update
iomap_readpage_iter() to advance the iter instead of returning the
number of bytes processed. In turn, drop the offset parameter and
sample the updated iter->pos at the start of the function. Update
the callers to loop based on remaining length in the current
iteration instead of number of bytes processed.

Signed-off-by: default avatarBrian Foster <bfoster@redhat.com>
Link: https://lore.kernel.org/r/20250224144757.237706-2-bfoster@redhat.com


Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatar"Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 30f53009

fs/iomap/buffered-io.c

+20 −25
Original line number Diff line number Diff line
@@ -362,15 +362,14 @@ static inline bool iomap_block_needs_zeroing(const struct iomap_iter *iter, 
		pos >= i_size_read(iter->inode);

}



static loff_t iomap_readpage_iter(const struct iomap_iter *iter,

		struct iomap_readpage_ctx *ctx, loff_t offset)

static loff_t iomap_readpage_iter(struct iomap_iter *iter,

		struct iomap_readpage_ctx *ctx)

{

	const struct iomap *iomap = &iter->iomap;

	loff_t pos = iter->pos + offset;

	loff_t length = iomap_length(iter) - offset;

	loff_t pos = iter->pos;

	loff_t length = iomap_length(iter);

	struct folio *folio = ctx->cur_folio;

	struct iomap_folio_state *ifs;

	loff_t orig_pos = pos;

	size_t poff, plen;

	sector_t sector;
@@ -434,25 +433,22 @@ static loff_t iomap_readpage_iter(const struct iomap_iter *iter, 
	 * we can skip trailing ones as they will be handled in the next

	 * iteration.

	 */

	return pos - orig_pos + plen;

	length = pos - iter->pos + plen;

	return iomap_iter_advance(iter, &length);

}



static loff_t iomap_read_folio_iter(const struct iomap_iter *iter,

static loff_t iomap_read_folio_iter(struct iomap_iter *iter,

		struct iomap_readpage_ctx *ctx)

{

	struct folio *folio = ctx->cur_folio;

	size_t offset = offset_in_folio(folio, iter->pos);

	loff_t length = min_t(loff_t, folio_size(folio) - offset,

			      iomap_length(iter));

	loff_t done, ret;



	for (done = 0; done < length; done += ret) {

		ret = iomap_readpage_iter(iter, ctx, done);

		if (ret <= 0)

	loff_t ret;



	while (iomap_length(iter)) {

		ret = iomap_readpage_iter(iter, ctx);

		if (ret)

			return ret;

	}



	return done;

	return 0;

}



int iomap_read_folio(struct folio *folio, const struct iomap_ops *ops)
@@ -489,15 +485,14 @@ int iomap_read_folio(struct folio *folio, const struct iomap_ops *ops) 
}

EXPORT_SYMBOL_GPL(iomap_read_folio);



static loff_t iomap_readahead_iter(const struct iomap_iter *iter,

static loff_t iomap_readahead_iter(struct iomap_iter *iter,

		struct iomap_readpage_ctx *ctx)

{

	loff_t length = iomap_length(iter);

	loff_t done, ret;

	loff_t ret;



	for (done = 0; done < length; done += ret) {

	while (iomap_length(iter)) {

		if (ctx->cur_folio &&

		    offset_in_folio(ctx->cur_folio, iter->pos + done) == 0) {

		    offset_in_folio(ctx->cur_folio, iter->pos) == 0) {

			if (!ctx->cur_folio_in_bio)

				folio_unlock(ctx->cur_folio);

			ctx->cur_folio = NULL;
@@ -506,12 +501,12 @@ static loff_t iomap_readahead_iter(const struct iomap_iter *iter, 
			ctx->cur_folio = readahead_folio(ctx->rac);

			ctx->cur_folio_in_bio = false;

		}

		ret = iomap_readpage_iter(iter, ctx, done);

		if (ret <= 0)

		ret = iomap_readpage_iter(iter, ctx);

		if (ret)

			return ret;

	}



	return done;

	return 0;

}



/**