From: Anatoly Burakov <anatoly.burakov@intel.com>
To: dev@dpdk.org, Robin Jarry <rjarry@redhat.com>
Subject: [PATCH v1 1/1] usertools/devbind: allow changing UID/GID for VFIO
Date: Mon, 2 Sep 2024 14:57:32 +0100 [thread overview]
Message-ID: <4cd0282dabfa59e715028ecf255468529655b487.1725285449.git.anatoly.burakov@intel.com> (raw)
Currently, when binding a device to VFIO, the UID/GID for the device will
always stay as system default (`root`). Yet, when running DPDK as non-root
user, one has to change the UID/GID of the device to match the user's
UID/GID to use the device.
This patch adds an option to `dpdk-devbind.py` to change the UID/GID of
the device when binding it to VFIO.
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
usertools/dpdk-devbind.py | 41 +++++++++++++++++++++++++++++++++++++--
1 file changed, 39 insertions(+), 2 deletions(-)
diff --git a/usertools/dpdk-devbind.py b/usertools/dpdk-devbind.py
index 078e8c387b..37e2b9972d 100755
--- a/usertools/dpdk-devbind.py
+++ b/usertools/dpdk-devbind.py
@@ -8,6 +8,8 @@
import subprocess
import argparse
import platform
+import grp
+import pwd
from glob import glob
from os.path import exists, basename
@@ -107,6 +109,8 @@
b_flag = None
status_flag = False
force_flag = False
+vfio_uid = ""
+vfio_gid = ""
args = []
@@ -462,6 +466,22 @@ def bind_one(dev_id, driver, force):
% (dev_id, filename, err))
+def own_one(dev_id, uid, gid):
+ """Set the IOMMU group ownership for a device"""
+ # find IOMMU group for a particular device
+ iommu_grp_base_path = os.path.join("/sys/bus/pci/devices", dev_id, "iommu_group")
+ try:
+ iommu_grp = os.path.basename(os.readlink(iommu_grp_base_path))
+ # we found IOMMU group, now find the device
+ dev_path = os.path.join("/dev/vfio", iommu_grp)
+ # set the ownership
+ _uid = pwd.getpwnam(uid).pw_uid if uid else -1
+ _gid = grp.getgrnam(gid).gr_gid if gid else -1
+ os.chown(dev_path, _uid, _gid)
+ except OSError as err:
+ sys.exit(f"Error: failed to read IOMMU group for {dev_id}: {err}")
+
+
def unbind_all(dev_list, force=False):
"""Unbind method, takes a list of device locations"""
@@ -482,7 +502,7 @@ def unbind_all(dev_list, force=False):
unbind_one(d, force)
-def bind_all(dev_list, driver, force=False):
+def bind_all(dev_list, driver, uid, gid, force=False):
"""Bind method, takes a list of device locations"""
global devices
@@ -510,6 +530,9 @@ def bind_all(dev_list, driver, force=False):
for d in dev_list:
bind_one(d, driver, force)
+ # if we're binding to vfio-pci, set the IOMMU user/group ownership if one was specified
+ if driver == "vfio-pci" and (uid or gid):
+ own_one(d, uid, gid)
# For kernels < 3.15 when binding devices to a generic driver
# (i.e. one that doesn't have a PCI ID table) using new_id, some devices
@@ -662,6 +685,8 @@ def parse_args():
global status_dev
global force_flag
global args
+ global vfio_uid
+ global vfio_gid
parser = argparse.ArgumentParser(
description='Utility to bind and unbind devices from Linux kernel',
@@ -707,6 +732,12 @@ def parse_args():
'--unbind',
action='store_true',
help="Unbind a device (equivalent to \"-b none\")")
+ parser.add_argument(
+ "-U", "--uid", help="For VFIO, specify the UID to set IOMMU group ownership"
+ )
+ parser.add_argument(
+ "-G", "--gid", help="For VFIO, specify the GID to set IOMMU group ownership"
+ )
parser.add_argument(
'--force',
action='store_true',
@@ -737,6 +768,10 @@ def parse_args():
b_flag = opt.bind
elif opt.unbind:
b_flag = "none"
+ if opt.uid:
+ vfio_uid = opt.uid
+ if opt.gid:
+ vfio_gid = opt.gid
args = opt.devices
if not b_flag and not status_flag:
@@ -764,11 +799,13 @@ def do_arg_actions():
global status_flag
global force_flag
global args
+ global vfio_uid
+ global vfio_gid
if b_flag in ["none", "None"]:
unbind_all(args, force_flag)
elif b_flag is not None:
- bind_all(args, b_flag, force_flag)
+ bind_all(args, b_flag, vfio_uid, vfio_gid, force_flag)
if status_flag:
if b_flag is not None:
clear_data()
--
2.43.5
next reply other threads:[~2024-09-02 13:57 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-09-02 13:57 Anatoly Burakov [this message]
2024-09-03 9:11 ` Burakov, Anatoly
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=4cd0282dabfa59e715028ecf255468529655b487.1725285449.git.anatoly.burakov@intel.com \
--to=anatoly.burakov@intel.com \
--cc=dev@dpdk.org \
--cc=rjarry@redhat.com \
/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).