lkml.org 
[lkml]   [2023]   [Mar]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2] scsi: ufs: mcq: Limit the amount of inflight requests
Date
in UFS, each request is designated via the triplet <iid, lun, task tag>.

In UFS4.0 the Initiator ID field is 8 bits wide, comprised of the
EXT_IID and IID fields. Together with the task tag (single byte), they
limit the driver's hw queues capacity.

---
v1 -> v2:
Attend Johannes's and Bart's comments

Signed-off-by: Avri Altman <avri.altman@wdc.com>
---
drivers/ufs/core/ufshcd.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 35a3bd95c5e4..cac7c9918c5b 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -8468,6 +8468,11 @@ static int ufshcd_alloc_mcq(struct ufs_hba *hba)
if (ret)
goto err;

+ if (hba->nutrs * hba->nr_hw_queues > SZ_64K - 1) {
+ dev_info(hba->dev, "there can be at most 64K inflight requests\n");
+ goto err;
+ }
+
/*
* Previously allocated memory for nutrs may not be enough in MCQ mode.
* Number of supported tags in MCQ mode may be larger than SDB mode.
--
2.17.1
\
 
 \ /
  Last update: 2023-03-31 09:51    [W:0.105 / U:1.836 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site