From: Logan Gunthorpe <logang@deltatee.com>
To: linux-nvme@lists.infradead.org
Cc: Logan Gunthorpe <logang@deltatee.com>,
Christoph Hellwig <hch@lst.de>,
Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>,
Sagi Grimberg <sagi@grimberg.me>
Subject: [PATCH v2 1/2] nvmet-passthru: Limit mdts by BIO_MAX_PAGES
Date: Fri, 16 Oct 2020 16:19:04 -0600 [thread overview]
Message-ID: <20201016221905.4686-1-logang@deltatee.com> (raw)
nvmet_passthru_map_sg() only supports mapping a single BIO, not a chain
so the effective maximum transfer should also be limitted by BIO_MAX_PAGES
(presently this works out to 1MB).
For PCI passthru devices the max_sectors would typically be more limitting
than BIO_MAX_PAGES, but this may not be true for all passthru devices.
Fixes: c1fef73f793b ("nvmet: add passthru code to process commands")
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
---
drivers/nvme/target/passthru.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/nvme/target/passthru.c b/drivers/nvme/target/passthru.c
index dacfa7435d0b..1ab88df3310f 100644
--- a/drivers/nvme/target/passthru.c
+++ b/drivers/nvme/target/passthru.c
@@ -26,7 +26,7 @@ static u16 nvmet_passthru_override_id_ctrl(struct nvmet_req *req)
struct nvme_ctrl *pctrl = ctrl->subsys->passthru_ctrl;
u16 status = NVME_SC_SUCCESS;
struct nvme_id_ctrl *id;
- u32 max_hw_sectors;
+ int max_hw_sectors;
int page_shift;
id = kzalloc(sizeof(*id), GFP_KERNEL);
@@ -48,6 +48,13 @@ static u16 nvmet_passthru_override_id_ctrl(struct nvmet_req *req)
max_hw_sectors = min_not_zero(pctrl->max_segments << (PAGE_SHIFT - 9),
pctrl->max_hw_sectors);
+ /*
+ * nvmet_passthru_map_sg is limitted to using a single bio so limit
+ * the mdts based on BIO_MAX_PAGES as well
+ */
+ max_hw_sectors = min_not_zero(BIO_MAX_PAGES << (PAGE_SHIFT - 9),
+ max_hw_sectors);
+
page_shift = NVME_CAP_MPSMIN(ctrl->cap) + 12;
id->mdts = ilog2(max_hw_sectors) + 9 - page_shift;
base-commit: bbf5c979011a099af5dc76498918ed7df445635b
--
2.20.1
_______________________________________________
Linux-nvme mailing list
Linux-nvme@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-nvme
next reply other threads:[~2020-10-16 22:19 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-16 22:19 Logan Gunthorpe [this message]
2020-10-16 22:19 ` [PATCH v2 2/2] nvmet-passthru: Cleanup nvmet_passthru_map_sg() Logan Gunthorpe
2020-10-19 11:20 ` [PATCH v2 1/2] nvmet-passthru: Limit mdts by BIO_MAX_PAGES Max Gurtovoy
2020-10-19 15:40 ` Logan Gunthorpe
[not found] ` <BYAPR04MB4965B1360F5F6A1D13FF1DD0861F0@BYAPR04MB4965.namprd04.prod.outlook.com>
2020-10-20 2:05 ` Logan Gunthorpe
2020-10-22 13:29 ` Christoph Hellwig
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=20201016221905.4686-1-logang@deltatee.com \
--to=logang@deltatee.com \
--cc=chaitanya.kulkarni@wdc.com \
--cc=hch@lst.de \
--cc=linux-nvme@lists.infradead.org \
--cc=sagi@grimberg.me \
/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).