From 803c98050569850be5fd51a2025c67622de887d9 Mon Sep 17 00:00:00 2001 From: Stefan Roesch Date: Fri, 18 Nov 2022 16:52:07 -0800 Subject: [PATCH] mm: add bdi_set_min_bytes() function This introduces the bdi_set_min_bytes() function. The min_bytes function does not store the min_bytes value. Instead it converts the min_bytes value into the corresponding ratio value. Link: https://lkml.kernel.org/r/20221119005215.3052436-13-shr@devkernel.io Signed-off-by: Stefan Roesch Cc: Chris Mason Cc: Jens Axboe Signed-off-by: Andrew Morton --- include/linux/backing-dev.h | 1 + mm/page-writeback.c | 14 ++++++++++++++ 2 files changed, 15 insertions(+) diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 8e04567..5726697 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -109,6 +109,7 @@ u64 bdi_get_min_bytes(struct backing_dev_info *bdi); u64 bdi_get_max_bytes(struct backing_dev_info *bdi); 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_min_bytes(struct backing_dev_info *bdi, u64 min_bytes); int bdi_set_max_bytes(struct backing_dev_info *bdi, u64 max_bytes); int bdi_set_strict_limit(struct backing_dev_info *bdi, unsigned int strict_limit); diff --git a/mm/page-writeback.c b/mm/page-writeback.c index cefee72..3d151e7 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -750,6 +750,20 @@ u64 bdi_get_min_bytes(struct backing_dev_info *bdi) return bdi_get_bytes(bdi->min_ratio); } +int bdi_set_min_bytes(struct backing_dev_info *bdi, u64 min_bytes) +{ + int ret; + unsigned long pages = min_bytes >> PAGE_SHIFT; + unsigned long min_ratio; + + ret = bdi_check_pages_limit(pages); + if (ret) + return ret; + + min_ratio = bdi_ratio_from_pages(pages); + return __bdi_set_min_ratio(bdi, min_ratio); +} + u64 bdi_get_max_bytes(struct backing_dev_info *bdi) { return bdi_get_bytes(bdi->max_ratio); -- 2.7.4