diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 439815cc1ab965c3937d500c55480af4d625c842..9c984ffc8a0aa926ffb975956682d46267a8ff9b 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -104,6 +104,7 @@ static inline unsigned long wb_stat_error(void) int bdi_set_min_ratio(struct backing_dev_info *bdi, unsigned int min_ratio); int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio); +int bdi_set_strict_limit(struct backing_dev_info *bdi, unsigned int strict_limit); /* * Flags in backing_dev_info::capability diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 7e9d8d857eccae53047699fe39549877cbec7b0e..3745b886722f8c50feffb30b556f7a2aff123d15 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -698,6 +698,21 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned max_ratio) } EXPORT_SYMBOL(bdi_set_max_ratio); +int bdi_set_strict_limit(struct backing_dev_info *bdi, unsigned int strict_limit) +{ + if (strict_limit > 1) + return -EINVAL; + + spin_lock_bh(&bdi_lock); + if (strict_limit) + bdi->capabilities |= BDI_CAP_STRICTLIMIT; + else + bdi->capabilities &= ~BDI_CAP_STRICTLIMIT; + spin_unlock_bh(&bdi_lock); + + return 0; +} + static unsigned long dirty_freerun_ceiling(unsigned long thresh, unsigned long bg_thresh) {