[dpdk-dev] [PATCH v4] usertools/dpdk-devbind: add support for PCI wildcards

[Bruce Richardson <bruce.richardson@intel.com>]

When binding or unbinding a range of devices, it can be useful to use
wildcards to specify the devices rather than repeating the same prefix
multiple times. We can use the python "glob" module to give us this
functionality - at least for PCI devices - by checking /sys for matching
files.

Examples of use from my system:

    ./dpdk-devbind.py -b vfio-pci 80:04.*
    ./dpdk-devbind.py -u 80:04.[2-7]

The first example binds eight devices, 80:04.0..80:04.7, to vfio-pci. The
second then unbinds six of those devices, 80:04.2..80:04.7, from any
driver.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>

---
V4: change path manipulation to use os.path.join and basename
    separated pci_glob out into separate function with doc string
    [dropped Ferruh's test-by due to scope of changes]
V3: fix typo in help text additions
V2: added help text additions
---
 usertools/dpdk-devbind.py | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/usertools/dpdk-devbind.py b/usertools/dpdk-devbind.py
index 86b6b53c40..6c23d243fa 100755
--- a/usertools/dpdk-devbind.py
+++ b/usertools/dpdk-devbind.py
@@ -8,7 +8,9 @@
 import os
 import getopt
 import subprocess
+from glob import glob
 from os.path import exists, abspath, dirname, basename
+from os.path import join as path_join
 
 if sys.version_info.major < 3:
     print("WARNING: Python 2 is deprecated for use in DPDK, and will not work in future releases.", file=sys.stderr)
@@ -89,6 +91,8 @@ def usage():
 where DEVICE1, DEVICE2 etc, are specified via PCI "domain:bus:slot.func" syntax
 or "bus:slot.func" syntax. For devices bound to Linux kernel drivers, they may
 also be referred to by Linux interface name e.g. eth0, eth1, em0, em1, etc.
+If devices are specified using PCI <domain:>bus:device:func format, then
+shell wildcards and ranges may be used, e.g. 80:04.*, 80:04.[0-3]
 
 Options:
     --help, --usage:
@@ -145,6 +149,9 @@ def usage():
 To bind 0000:02:00.0 and 0000:02:00.1 to the ixgbe kernel driver
         %(argv0)s -b ixgbe 02:00.0 02:00.1
 
+To bind all functions on device 0000:02:00 to ixgbe kernel driver
+        %(argv0)s -b ixgbe 02:00.*
+
     """ % locals())  # replace items from local variables
 
 
@@ -648,6 +655,19 @@ def show_status():
     if status_dev == "misc" or status_dev == "all":
         show_device_status(misc_devices, "Misc (rawdev)")
 
+
+def pci_glob(arg):
+    '''Returns a list containing either:
+    * List of PCI B:D:F matching arg, using shell wildcards e.g. 80:04.*
+    * Only the passed arg if matching list is empty'''
+    sysfs_path = "/sys/bus/pci/devices"
+    for _glob in [arg, '0000:' + arg]:
+        paths = [basename(path) for path in glob(path_join(sysfs_path, _glob))]
+        if paths:
+            return paths
+    return [arg]
+
+
 def parse_args():
     '''Parses the command-line arguments given by the user and takes the
     appropriate action for each'''
@@ -689,6 +709,11 @@ def parse_args():
             else:
                 b_flag = arg
 
+    # resolve any PCI globs in the args
+    new_args = []
+    for arg in args:
+        new_args.extend(pci_glob(arg))
+    args = new_args
 
 def do_arg_actions():
     '''do the actual action requested by the user'''
-- 
2.25.1