diff mbox series

[6/7] bcache: Use 64-bit arithmetic instead of 32-bit

Message ID 20210411134316.80274-7-colyli@suse.de (mailing list archive)
State New, archived
Headers show
Series bcache patches for Linux 5.13 -- 1st wave | expand

Commit Message

Coly Li April 11, 2021, 1:43 p.m. UTC 
From: "Gustavo A. R. Silva" <gustavoars@kernel.org>

Cast multiple variables to (int64_t) in order to give the compiler
complete information about the proper arithmetic to use. Notice that
these variables are being used in contexts that expect expressions of
type int64_t  (64 bit, signed). And currently, such expressions are
being evaluated using 32-bit arithmetic.

Fixes: d0cf9503e908 ("octeontx2-pf: ethtool fec mode support")
Addresses-Coverity-ID: 1501724 ("Unintentional integer overflow")
Addresses-Coverity-ID: 1501725 ("Unintentional integer overflow")
Addresses-Coverity-ID: 1501726 ("Unintentional integer overflow")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Coly Li <colyli@suse.de>
---
 drivers/md/bcache/writeback.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index bcd550a2b0da..8120da278161 100644
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -110,13 +110,13 @@  static void __update_writeback_rate(struct cached_dev *dc)
 		int64_t fps;
 
 		if (c->gc_stats.in_use <= BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID) {
-			fp_term = dc->writeback_rate_fp_term_low *
+			fp_term = (int64_t)dc->writeback_rate_fp_term_low *
 			(c->gc_stats.in_use - BCH_WRITEBACK_FRAGMENT_THRESHOLD_LOW);
 		} else if (c->gc_stats.in_use <= BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH) {
-			fp_term = dc->writeback_rate_fp_term_mid *
+			fp_term = (int64_t)dc->writeback_rate_fp_term_mid *
 			(c->gc_stats.in_use - BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID);
 		} else {
-			fp_term = dc->writeback_rate_fp_term_high *
+			fp_term = (int64_t)dc->writeback_rate_fp_term_high *
 			(c->gc_stats.in_use - BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH);
 		}
 		fps = div_s64(dirty, dirty_buckets) * fp_term;