diff options
Diffstat (limited to 'drivers/md/raid5.c')
-rw-r--r-- | drivers/md/raid5.c | 64 |
1 files changed, 41 insertions, 23 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 825fa629db33..c14cf2410365 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5899,6 +5899,39 @@ out: return ret; } +enum reshape_loc { + LOC_NO_RESHAPE, + LOC_AHEAD_OF_RESHAPE, + LOC_INSIDE_RESHAPE, + LOC_BEHIND_RESHAPE, +}; + +static enum reshape_loc get_reshape_loc(struct mddev *mddev, + struct r5conf *conf, sector_t logical_sector) +{ + sector_t reshape_progress, reshape_safe; + /* + * Spinlock is needed as reshape_progress may be + * 64bit on a 32bit platform, and so it might be + * possible to see a half-updated value + * Of course reshape_progress could change after + * the lock is dropped, so once we get a reference + * to the stripe that we think it is, we will have + * to check again. + */ + spin_lock_irq(&conf->device_lock); + reshape_progress = conf->reshape_progress; + reshape_safe = conf->reshape_safe; + spin_unlock_irq(&conf->device_lock); + if (reshape_progress == MaxSector) + return LOC_NO_RESHAPE; + if (ahead_of_reshape(mddev, logical_sector, reshape_progress)) + return LOC_AHEAD_OF_RESHAPE; + if (ahead_of_reshape(mddev, logical_sector, reshape_safe)) + return LOC_INSIDE_RESHAPE; + return LOC_BEHIND_RESHAPE; +} + static enum stripe_result make_stripe_request(struct mddev *mddev, struct r5conf *conf, struct stripe_request_ctx *ctx, sector_t logical_sector, struct bio *bi) @@ -5913,28 +5946,14 @@ static enum stripe_result make_stripe_request(struct mddev *mddev, seq = read_seqcount_begin(&conf->gen_lock); if (unlikely(conf->reshape_progress != MaxSector)) { - /* - * Spinlock is needed as reshape_progress may be - * 64bit on a 32bit platform, and so it might be - * possible to see a half-updated value - * Of course reshape_progress could change after - * the lock is dropped, so once we get a reference - * to the stripe that we think it is, we will have - * to check again. - */ - spin_lock_irq(&conf->device_lock); - if (ahead_of_reshape(mddev, logical_sector, - conf->reshape_progress)) { - previous = 1; - } else { - if (ahead_of_reshape(mddev, logical_sector, - conf->reshape_safe)) { - spin_unlock_irq(&conf->device_lock); - ret = STRIPE_SCHEDULE_AND_RETRY; - goto out; - } + enum reshape_loc loc = get_reshape_loc(mddev, conf, + logical_sector); + if (loc == LOC_INSIDE_RESHAPE) { + ret = STRIPE_SCHEDULE_AND_RETRY; + goto out; } - spin_unlock_irq(&conf->device_lock); + if (loc == LOC_AHEAD_OF_RESHAPE) + previous = 1; } new_sector = raid5_compute_sector(conf, logical_sector, previous, @@ -6112,8 +6131,7 @@ static bool raid5_make_request(struct mddev *mddev, struct bio * bi) /* Bail out if conflicts with reshape and REQ_NOWAIT is set */ if ((bi->bi_opf & REQ_NOWAIT) && (conf->reshape_progress != MaxSector) && - !ahead_of_reshape(mddev, logical_sector, conf->reshape_progress) && - ahead_of_reshape(mddev, logical_sector, conf->reshape_safe)) { + get_reshape_loc(mddev, conf, logical_sector) == LOC_INSIDE_RESHAPE) { bio_wouldblock_error(bi); if (rw == WRITE) md_write_end(mddev); |