From: Xiang Chen <chenxiang66@hisilicon.com>
Date: Mon, 5 Aug 2019 21:48:05 +0800
Subject: [PATCH] scsi: hisi_sas: Make slot buf minimum allocation of PAGE_SIZE
References: bsc#1156419,jsc#SLE-8281
Git-commit: 599aefc81effaaf78c02d44461f7157f22ee3b1d
Patch-mainline: v5.4-rc1
For a system with PAGE_SIZE of 16K or 64K, the size every time we want to
alloc may be small like 4K, but for function dmam_alloc_coherent(), the
least size it allocates is PAGE_SIZE, so it will waste much memory for the
situation.
To solve the issue, limit the minimum allocation size of slot buf to
PAGE_SIZE.
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/hisi_sas/hisi_sas_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 7efa8dfa0cc1..39ae69e42d26 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -2389,7 +2389,7 @@ int hisi_sas_alloc(struct hisi_hba *hisi_hba)
else
sz_slot_buf_ru = sizeof(struct hisi_sas_slot_buf_table);
sz_slot_buf_ru = roundup(sz_slot_buf_ru, 64);
- s = lcm(max_command_entries_ru, sz_slot_buf_ru);
+ s = max(lcm(max_command_entries_ru, sz_slot_buf_ru), PAGE_SIZE);
blk_cnt = (max_command_entries_ru * sz_slot_buf_ru) / s;
slots_per_blk = s / sz_slot_buf_ru;
--
2.16.4