On 02/03/2021 11:50 PM, Christoph Hellwig wrote:
On Wed, Feb 03, 2021 at 09:45:30PM +0800, Xiao Ni wrote:
+static struct bio *raid10_split_bio(struct r10conf *conf,
+ struct bio *bio, sector_t sectors, bool want_first)
+{
+ struct bio *split;
+
+ split = bio_split(bio, sectors, GFP_NOIO, &conf->bio_split);
+ bio_chain(split, bio);
+ allow_barrier(conf);
+ if (want_first) {
+ submit_bio_noacct(bio);
+ bio = split;
+ } else
+ submit_bio_noacct(split);
+ wait_barrier(conf);
+
+ return bio;
I'm not sure this helper makes much sense given that the two different
cases could just be open coded into the two callers.
It makes sense. At first I want to make the codes look like simpler. But
as you said, they are two
different cases. We can code openly into the two callers.
+ /* raid10_remove_disk uses smp_mb to make sure rdev is set to
+ * replacement before setting replacement to NULL. It can read
+ * rdev first without barrier protect even replacment is NULL
+ */
Not the normal kernel comment style.
+/* There are some limitations to handle discard bio
+ * 1st, the discard size is bigger than stripe_size*2.
+ * 2st, if the discard bio spans reshape progress, we use the old way to
+ * handle discard bio
+ */
Same here.
+static int raid10_handle_discard(struct mddev *mddev, struct bio *bio)
+{
+ struct r10conf *conf = mddev->private;
+ struct geom *geo = &conf->geo;
+ struct r10bio *r10_bio;
+
+ int disk;
+ sector_t chunk;
+ unsigned int stripe_size;
+ unsigned int stripe_data_disks;
+ sector_t split_size;
+
+ sector_t bio_start, bio_end;
Empty lines between variabe declarations also are kinda strange.
+ stripe_data_disks = geo->near_copies ?
+ geo->raid_disks / geo->near_copies +
+ geo->raid_disks % geo->near_copies :
+ geo->raid_disks;
Normal style would be an if/else here.
+
+ bio_start = bio->bi_iter.bi_sector;
+ bio_end = bio_end_sector(bio);
+
+ /* Maybe one discard bio is smaller than strip size or across one stripe
+ * and discard region is larger than one stripe size. For far offset layout,
While there are occasional exceptions to the 80 char line rule, a block
comment should never qualify.
+ * if the discard region is not aligned with stripe size, there is hole
+ * when we submit discard bio to member disk. For simplicity, we only
+ * handle discard bio which discard region is bigger than stripe_size*2
+ */
+ if (bio_sectors(bio) < stripe_size*2)
missing whitespaces around the *.
I'll fix these style problems.
Thanks
Xiao
