From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4480413D897; Wed, 5 Feb 2025 18:58:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738781882; cv=none; b=g7NEtlm2tdFapTEb3YwXts9kDdnFKybrWkvDKGWdb49xKYa1x7goM7TfMu4JAJZWcWR/HQvaULWnhO6RyA/Iz6p25yoZH24myKsJgfAD2R7eRF+VvGgg+O9ktMLs0/9+kRaTiQjV0BEOVRO7tsbgGn9QU2YRlrB18cPn+hehK9U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738781882; c=relaxed/simple; bh=Hceogdek36+SZAqauV6t7bwwMBUi65kxQD75Yha6DtQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Ui2HgQLVR3khdnWoJHShqNq6YSkN/giWlasNFk7dKJIn5PJcrjJRGUvvu/ucODCUmcxZ6ohmp2cvSgM6tB1C7YgpLiXBTYcTx0wrLzCTUcNionultE0zC6qGNdgIpJhE8gmiKN2sE7CTudv54wsIGFQixw4ziQjx2QmzIwRP/Ow= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=L1zHlavC; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="L1zHlavC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C05CC4CED1; Wed, 5 Feb 2025 18:58:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1738781881; bh=Hceogdek36+SZAqauV6t7bwwMBUi65kxQD75Yha6DtQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=L1zHlavCQGfR6rdR554HHeAcWUhIrgDv7T2V7kHUf7Xau0/K+5TirCnSgtq1mjaaN Dp7Cw7uQH1OkgpX0lBRVfeZlTSLRjONjLhBODkU3BaS2El6Kgxl6DAuquV95NA6ZDf T8msNSTuYR/mwUSVzJEOdDkIMoNe8Sgjt8AN/Bfx8tO4MkCHqLEnELAZhC+OD7hvXI YY99F2y01rZZrSJes/UFv0SBt/aFSQy4u/NTmqCn61l7sgLd3ZsMGoG8KGMm7WSPAV IO4+2wQvN69b+RcaueKMProEFfYx8t0HvSBKSWTNWaxFva0bp3lJk6se1TkBzd/fu9 E7Uxdk24UOUZQ== Date: Wed, 5 Feb 2025 10:58:01 -0800 From: "Darrick J. Wong" To: Brian Foster Cc: linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, Christoph Hellwig Subject: Re: [PATCH v5 06/10] iomap: export iomap_iter_advance() and return remaining length Message-ID: <20250205185801.GO21808@frogsfrogsfrogs> References: <20250205135821.178256-1-bfoster@redhat.com> <20250205135821.178256-7-bfoster@redhat.com> Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250205135821.178256-7-bfoster@redhat.com> On Wed, Feb 05, 2025 at 08:58:17AM -0500, Brian Foster wrote: > As a final step for generic iter advance, export the helper and > update it to return the remaining length of the current iteration > after the advance. This will usually be 0 in the iomap_iter() case, > but will be useful for the various operations that iterate on their > own and will be updated to advance as they progress. > > Signed-off-by: Brian Foster > Reviewed-by: Christoph Hellwig > --- > fs/iomap/iter.c | 22 ++++++++-------------- > include/linux/iomap.h | 1 + > 2 files changed, 9 insertions(+), 14 deletions(-) > > diff --git a/fs/iomap/iter.c b/fs/iomap/iter.c > index 8e0746ad80bd..cdba24dbbfd7 100644 > --- a/fs/iomap/iter.c > +++ b/fs/iomap/iter.c > @@ -15,22 +15,16 @@ static inline void iomap_iter_reset_iomap(struct iomap_iter *iter) > } > > /* > - * Advance to the next range we need to map. > - * > - * If the iomap is marked IOMAP_F_STALE, it means the existing map was not fully > - * processed - it was aborted because the extent the iomap spanned may have been > - * changed during the operation. In this case, the iteration behaviour is to > - * remap the unprocessed range of the iter, and that means we may need to remap > - * even when we've made no progress (i.e. count = 0). Hence the "finished > - * iterating" case needs to distinguish between (count = 0) meaning we are done > - * and (count = 0 && stale) meaning we need to remap the entire remaining range. > + * Advance the current iterator position and return the length remaining for the > + * current mapping. This last sentence should state that the remaining length is returned via @count as an outparam and not through the function's return value. Otherwise looks ok to me. --D > */ > -static inline int iomap_iter_advance(struct iomap_iter *iter, s64 count) > +int iomap_iter_advance(struct iomap_iter *iter, u64 *count) > { > - if (WARN_ON_ONCE(count > iomap_length(iter))) > + if (WARN_ON_ONCE(*count > iomap_length(iter))) > return -EIO; > - iter->pos += count; > - iter->len -= count; > + iter->pos += *count; > + iter->len -= *count; > + *count = iomap_length(iter); > return 0; > } > > @@ -93,7 +87,7 @@ int iomap_iter(struct iomap_iter *iter, const struct iomap_ops *ops) > * advanced at all (i.e. no work was done for some reason) unless the > * mapping has been marked stale and needs to be reprocessed. > */ > - ret = iomap_iter_advance(iter, processed); > + ret = iomap_iter_advance(iter, &processed); > if (!ret && iter->len > 0) > ret = 1; > if (ret > 0 && !iter->processed && !stale) > diff --git a/include/linux/iomap.h b/include/linux/iomap.h > index f5ca71ac2fa2..f304c602e5fe 100644 > --- a/include/linux/iomap.h > +++ b/include/linux/iomap.h > @@ -229,6 +229,7 @@ struct iomap_iter { > }; > > int iomap_iter(struct iomap_iter *iter, const struct iomap_ops *ops); > +int iomap_iter_advance(struct iomap_iter *iter, u64 *count); > > /** > * iomap_length_trim - trimmed length of the current iomap iteration > -- > 2.48.1 > >