kernel/linux.git/net/wireless/debugfs.c, branch v6.19.11

wifi: cfg80211: Add parameters to radio-specific debugfs directories

2025-10-27T08:18:41+00:00

In multi-radio wiphy architecture, where a single wiphy can have multiple radios tied to it, radio specific configuration parameters and global wiphy parameters are maintained for the entire physical device and common to all radios. But, each radio in a wiphy can have different values for each radio configuration parameter like RTS threshold. With the current debugfs directory structure, the values of global wiphy configuration parameters can be viewed, but, values of individual radio configuration parameters cannot be viewed. To address this requirement, maintain separate entries of each radio configuration parameter i.e., RTS threshold in corresponding radio- specific debugfs directory. This way, radio-specific configuration parameters can be maintained along with global wiphy configuration parameters. Whenever the values are changed for one radio, the values for rest of the radios in the wiphy and the global wiphy parameter value will remain intact. Sample output: /# iw phy#0 set rts 100 radio 1 /# iw phy#0 set rts 468 radio 0 /# cat /sys/kernel/debug/ieee80211/phy0/rts_threshold -1 /# cat /sys/kernel/debug/ieee80211/phy0/radio0/radio_rts_threshold 468 /# cat /sys/kernel/debug/ieee80211/phy0/radio1/radio_rts_threshold 100 /# iw phy#0 set rts 500 /# cat /sys/kernel/debug/ieee80211/phy0/rts_threshold 500 /# cat /sys/kernel/debug/ieee80211/phy0/radio0/radio_rts_threshold 500 /# cat /sys/kernel/debug/ieee80211/phy0/radio1/radio_rts_threshold 500 Signed-off-by: Roopni Devanathan Link: https://patch.msgid.link/20251024044649.483557-3-quic_rdevanat@quicinc.com Signed-off-by: Johannes Berg

wifi: cfg80211: add locked debugfs wrappers

2023-11-27T10:24:58+00:00

Add wrappers for debugfs files that should be called with the wiphy mutex held, while the file is also to be removed under the wiphy mutex. This could otherwise deadlock when a file is trying to acquire the wiphy mutex while the code removing it holds the mutex but waits for the removal. This actually works by pushing the execution of the read or write handler to a wiphy work that can be cancelled using the debugfs cancellation API. Signed-off-by: Johannes Berg

wifi: cfg80211: debugfs: fix return type in ht40allow_map_read()

2022-08-25T08:04:46+00:00

The return type is supposed to be ssize_t, which is signed long, but "r" was declared as unsigned int. This means that on 64 bit systems we return positive values instead of negative error codes. Fixes: 80a3511d70e8 ("cfg80211: add debugfs HT40 allow map") Signed-off-by: Dan Carpenter Link: https://lore.kernel.org/r/YutvOQeJm0UjLhwU@kili Signed-off-by: Johannes Berg

cfg80211: avoid holding the RTNL when calling the driver

2021-01-26T10:55:50+00:00

Currently, _everything_ in cfg80211 holds the RTNL, and if you have a slow USB device (or a few) you can get some bad lock contention on that. Fix that by re-adding a mutex to each wiphy/rdev as we had at some point, so we have locking for the wireless_dev lists and all the other things in there, and also so that drivers still don't have to worry too much about it (they still won't get parallel calls for a single device). Then, we can restrict the RTNL to a few cases where we add or remove interfaces and really need the added protection. Some of the global list management still also uses the RTNL, since we need to have it anyway for netdev management, but we only hold the RTNL for very short periods of time here. Link: https://lore.kernel.org/r/20210122161942.81df9f5e047a.I4a8e1a60b18863ea8c5e6d3a0faeafb2d45b2f40@changeid Tested-by: Marek Szyprowski [marvell driver issues] Signed-off-by: Johannes Berg

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55+00:00

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

cfg80211 debugfs: Cleanup some checkpatch issues

2017-02-08T08:15:59+00:00

This fixes the checkpatch.pl warnings: * Macros should not use a trailing semicolon. * Spaces required around that '='. * Symbolic permissions 'S_IRUGO' are not preferred. Signed-off-by: Dmitriy Pichugin Signed-off-by: Johannes Berg

cfg80211: remove enum ieee80211_band

2016-04-12T13:56:15+00:00

This enum is already perfectly aliased to enum nl80211_band, and the only reason for it is that we get IEEE80211_NUM_BANDS out of it. There's no really good reason to not declare the number of bands in nl80211 though, so do that and remove the cfg80211 one. Signed-off-by: Johannes Berg

mac80211: fix some snprintf misuses

2013-10-01T10:16:51+00:00

In some debugfs related functions snprintf was used while scnprintf should have been used instead. (blindly adding the return value of snprintf and supplying it to the next snprintf might result in buffer overflow when the input is too big) Signed-off-by: Eliad Peller Signed-off-by: Johannes Berg

cfg80211: vastly simplify locking

2013-05-24T22:02:15+00:00

Virtually all code paths in cfg80211 already (need to) hold the RTNL. As such, there's little point in having another four mutexes for various parts of the code, they just cause lock ordering issues (and much of the time, the RTNL and a few of the others need thus be held.) Simplify all this by getting rid of the extra four mutexes and just use the RTNL throughout. Only a few code changes were needed to do this and we can get rid of a work struct for bonus points. Signed-off-by: Johannes Berg

simple_open: automatically convert to simple_open()

2012-04-05T22:25:50+00:00

Many users of debugfs copy the implementation of default_open() when they want to support a custom read/write function op. This leads to a proliferation of the default_open() implementation across the entire tree. Now that the common implementation has been consolidated into libfs we can replace all the users of this function with simple_open(). This replacement was done with the following semantic patch: @ open @ identifier open_f != simple_open; identifier i, f; @@ -int open_f(struct inode *i, struct file *f) -{ ( -if (i->i_private) -f->private_data = i->i_private; | -f->private_data = i->i_private; ) -return 0; -} @ has_open depends on open @ identifier fops; identifier open.open_f; @@ struct file_operations fops = { ... -.open = open_f, +.open = simple_open, ... }; [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Stephen Boyd Cc: Greg Kroah-Hartman Cc: Al Viro Cc: Julia Lawall Acked-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds