| Message ID | 20220614090934.570632-3-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/6] block: factor out a chunk_size_left helper | expand |
On Tue, Jun 14 2022 at 5:09P -0400, Christoph Hellwig <hch@lst.de> wrote: > max_io_len always passes an explicitly non-zero chunk_sectors into > blk_max_size_offset. That means much of blk_max_size_offset is not > needed and can be open coded to simplify the code. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > drivers/md/dm.c | 17 ++++++----------- > 1 file changed, 6 insertions(+), 11 deletions(-) > > diff --git a/drivers/md/dm.c b/drivers/md/dm.c > index d8f16183bf27c..0514358a1f8e5 100644 > --- a/drivers/md/dm.c > +++ b/drivers/md/dm.c > @@ -1079,23 +1079,18 @@ static sector_t max_io_len(struct dm_target *ti, sector_t sector) > { > sector_t target_offset = dm_target_offset(ti, sector); > sector_t len = max_io_len_target_boundary(ti, target_offset); > - sector_t max_len; > > /* > * Does the target need to split IO even further? > * - varied (per target) IO splitting is a tenet of DM; this > * explains why stacked chunk_sectors based splitting via > - * blk_max_size_offset() isn't possible here. So pass in > - * ti->max_io_len to override stacked chunk_sectors. > + * blk_queue_split() isn't possible here. > */ > - if (ti->max_io_len) { > - max_len = blk_max_size_offset(ti->table->md->queue, > - target_offset, ti->max_io_len); > - if (len > max_len) > - len = max_len; > - } > - > - return len; > + if (!ti->max_io_len) > + return len; > + return min_t(sector_t, len, > + min(queue_max_sectors(ti->table->md->queue), > + blk_chunk_sectors_left(target_offset, ti->max_io_len))); > } > > int dm_set_target_max_io_len(struct dm_target *ti, sector_t len) > -- > 2.30.2 > Not in love with the nested min() but don't have a better suggestion. Reviewed-by: Mike Snitzer <snitzer@kernel.org>
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index d8f16183bf27c..0514358a1f8e5 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1079,23 +1079,18 @@ static sector_t max_io_len(struct dm_target *ti, sector_t sector) { sector_t target_offset = dm_target_offset(ti, sector); sector_t len = max_io_len_target_boundary(ti, target_offset); - sector_t max_len; /* * Does the target need to split IO even further? * - varied (per target) IO splitting is a tenet of DM; this * explains why stacked chunk_sectors based splitting via - * blk_max_size_offset() isn't possible here. So pass in - * ti->max_io_len to override stacked chunk_sectors. + * blk_queue_split() isn't possible here. */ - if (ti->max_io_len) { - max_len = blk_max_size_offset(ti->table->md->queue, - target_offset, ti->max_io_len); - if (len > max_len) - len = max_len; - } - - return len; + if (!ti->max_io_len) + return len; + return min_t(sector_t, len, + min(queue_max_sectors(ti->table->md->queue), + blk_chunk_sectors_left(target_offset, ti->max_io_len))); } int dm_set_target_max_io_len(struct dm_target *ti, sector_t len)
max_io_len always passes an explicitly non-zero chunk_sectors into blk_max_size_offset. That means much of blk_max_size_offset is not needed and can be open coded to simplify the code. Signed-off-by: Christoph Hellwig <hch@lst.de> --- drivers/md/dm.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-)