From: Peter Chen <peter.chen@nxp.com>
To: balbi@kernel.org
Cc: linux-usb@vger.kernel.org, linux-imx@nxp.com,
Peter Chen <peter.chen@nxp.com>, Jun Li <jun.li@nxp.com>,
stable <stable@vger.kernel.org>
Subject: [PATCH 1/1] usb: gadget: f_fs: set req->num_sgs as 0 for sync io mode
Date: Thu, 12 Dec 2019 11:59:20 +0800 [thread overview]
Message-ID: <1576123160-28931-1-git-send-email-peter.chen@nxp.com> (raw)
The UDC core uses req->num_sgs to judge if scatter buffer list is used.
Eg: usb_gadget_map_request_by_dev. For f_fs sync io mode, the request
is re-used for each request, so if the 1st request->length > PAGE_SIZE,
and the 2nd request->length is < PAGE_SIZE, the f_fs uses the 1st
req->num_sgs for the 2nd request, it causes the UDC core get the wrong
req->num_sgs value (The 2nd request doesn't use sg).
We set req->num_sgs as 0 for each request at non-sg transfer case to
fix it.
Cc: Jun Li <jun.li@nxp.com>
Cc: stable <stable@vger.kernel.org>
Fixes: 772a7a724f69 ("usb: gadget: f_fs: Allow scatter-gather buffers")
Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
drivers/usb/gadget/function/f_fs.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index eedd926cc578..b5a1bfc2fc7e 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -1106,7 +1106,6 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
req->num_sgs = io_data->sgt.nents;
} else {
req->buf = data;
- req->num_sgs = 0;
}
req->length = data_len;
--
2.17.1
next reply other threads:[~2019-12-12 4:01 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-12 3:59 Peter Chen [this message]
2019-12-12 6:43 ` [PATCH 1/1] usb: gadget: f_fs: set req->num_sgs as 0 for sync io mode Felipe Balbi
2019-12-12 8:09 ` Peter Chen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1576123160-28931-1-git-send-email-peter.chen@nxp.com \
--to=peter.chen@nxp.com \
--cc=balbi@kernel.org \
--cc=jun.li@nxp.com \
--cc=linux-imx@nxp.com \
--cc=linux-usb@vger.kernel.org \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).