kernel/linux.git/drivers/thunderbolt/ctl.c, branch v4.14.286

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

thunderbolt: Fix reset response_type

2017-08-28T14:21:32+00:00

There is a mistake here where we accidentally use sizeof(TB_CFG_PKG_RESET) instead of just TB_CFG_PKG_RESET. The size of an int is 4 so it's the same as TB_CFG_PKG_NOTIFY_ACK. Fixes: d7f781bfdbf4 ("thunderbolt: Rework control channel to be more reliable") Reported-by: Colin King Signed-off-by: Dan Carpenter Acked-by: Mika Westerberg Cc: stable # 4.13 Signed-off-by: Greg Kroah-Hartman

thunderbolt: Add support for Internal Connection Manager (ICM)

2017-06-09T09:42:43+00:00

Starting from Intel Falcon Ridge the internal connection manager running on the Thunderbolt host controller has been supporting 4 security levels. One reason for this is to prevent DMA attacks and only allow connecting devices the user trusts. The internal connection manager (ICM) is the preferred way of connecting Thunderbolt devices over software only implementation typically used on Macs. The driver communicates with ICM using special Thunderbolt ring 0 (control channel) messages. In order to handle these messages we add support for the ICM messages to the control channel. The security levels are as follows: none - No security, all tunnels are created automatically user - User needs to approve the device before tunnels are created secure - User need to approve the device before tunnels are created. The device is sent a challenge on future connects to be able to verify it is actually the approved device. dponly - Only Display Port and USB tunnels can be created and those are created automatically. The security levels are typically configurable from the system BIOS and by default it is set to "user" on many systems. In this patch each Thunderbolt device will have either one or two new sysfs attributes: authorized and key. The latter appears for devices that support secure connect. In order to identify the device the user can read identication information, including UUID and name of the device from sysfs and based on that make a decision to authorize the device. The device is authorized by simply writing 1 to the "authorized" sysfs attribute. This is following the USB bus device authorization mechanism. The secure connect requires an additional challenge step (writing 2 to the "authorized" attribute) in future connects when the key has already been stored to the NVM of the device. Non-ICM systems (before Alpine Ridge) continue to use the existing functionality and the security level is set to none. For systems with Alpine Ridge, even on Apple hardware, we will use ICM. This code is based on the work done by Amir Levy and Michael Jamet. Signed-off-by: Michael Jamet Signed-off-by: Mika Westerberg Reviewed-by: Yehezkel Bernat Reviewed-by: Andy Shevchenko Signed-off-by: Andreas Noever Signed-off-by: Greg Kroah-Hartman

thunderbolt: Rework control channel to be more reliable

2017-06-09T09:42:43+00:00

If a request times out the response might arrive right after the request is failed. This response is pushed to the kfifo and next request will read it instead. Since it most likely will not pass our validation checks in parse_header() the next request will fail as well, and response to that request will be pushed to the kfifo, ad infinitum. We end up in a situation where all requests fail and no devices can be added anymore until the driver is unloaded and reloaded again. To overcome this, rework the control channel so that we will have a queue of outstanding requests. Each request will be handled in turn and the response is validated against what is expected. Unexpected packets (for example responses for requests that have been timed out) are dropped. This model is copied from Greybus implementation with small changes here and there to get it cope with Thunderbolt control packets. In addition the configuration packets support sequence number which the switch is supposed to copy from the request to response. We use this to drop responses that are already timed out. Taking advantage of the sequence number, we automatically retry configuration read/write 4 times before giving up. Also timeout is not a programming error so there is no need to trigger a scary backtrace (WARN), instead we just log a warning. After all Thunderbolt devices are hot-pluggable by definition which means user can unplug a device any time and that is totally acceptable. With this change there is no need to take the global domain lock when sending configuration packets anymore. This is useful when we add support for cross-domain (XDomain) communication later on. Signed-off-by: Mika Westerberg Reviewed-by: Yehezkel Bernat Reviewed-by: Michael Jamet Reviewed-by: Andy Shevchenko Signed-off-by: Andreas Noever Signed-off-by: Greg Kroah-Hartman

thunderbolt: Let the connection manager handle all notifications

2017-06-09T09:42:42+00:00

Currently the control channel (ctl.c) handles the one supported notification (PLUG_EVENT) and sends back ACK accordingly. However, we are going to add support for the internal connection manager (ICM) that needs to handle a different notifications. So instead of dealing everything in the control channel, we change the callback to take an arbitrary thunderbolt packet and convert the native connection manager to handle the event itself. In addition we only push replies we know of to the response FIFO. Everything else is treated as notification (or request) and is expected to be dealt by the connection manager implementation. Signed-off-by: Mika Westerberg Reviewed-by: Yehezkel Bernat Reviewed-by: Michael Jamet Reviewed-by: Andy Shevchenko Signed-off-by: Andreas Noever Signed-off-by: Greg Kroah-Hartman

thunderbolt: Expose make_header() to other files

2017-06-09T09:42:42+00:00

We will be using this function in files introduced in subsequent patches. While there the function is renamed to tb_cfg_make_header() following tb_cfg_get_route(). Signed-off-by: Mika Westerberg Reviewed-by: Yehezkel Bernat Reviewed-by: Michael Jamet Reviewed-by: Andy Shevchenko Signed-off-by: Andreas Noever Signed-off-by: Greg Kroah-Hartman

thunderbolt: Expose get_route() to other files

2017-06-09T09:42:42+00:00

We are going to use it when we change the connection manager to handle events itself. Also rename it to follow naming convention used in functions exposed in ctl.h. Signed-off-by: Mika Westerberg Reviewed-by: Yehezkel Bernat Reviewed-by: Michael Jamet Reviewed-by: Andy Shevchenko Signed-off-by: Andreas Noever Signed-off-by: Greg Kroah-Hartman

thunderbolt: Move control channel messages to tb_msgs.h

2017-06-09T09:42:42+00:00

We will be forwarding notifications received from the control channel to the connection manager implementations. This way they can decide what to do if anything when a notification is received. To be able to use control channel messages from other files, move them to tb_msgs.h. No functional changes intended. Signed-off-by: Mika Westerberg Reviewed-by: Yehezkel Bernat Reviewed-by: Michael Jamet Reviewed-by: Andy Shevchenko Signed-off-by: Andreas Noever Signed-off-by: Greg Kroah-Hartman

thunderbolt: Allow passing NULL to tb_ctl_free()

2017-06-09T09:42:41+00:00

Following the usual pattern used in many places, we allow passing NULL pointer to tb_ctl_free(). Then the user can call the function regardless if it has allocated control channel or not making the code bit simpler. Suggested-by: Andy Shevchenko Signed-off-by: Mika Westerberg Signed-off-by: Andreas Noever Signed-off-by: Greg Kroah-Hartman

thunderbolt: Add MSI-X support

2017-06-09T09:42:41+00:00

Intel Thunderbolt controllers support up to 16 MSI-X vectors. Using MSI-X is preferred over MSI or legacy interrupt and may bring additional performance because there is no need to check the status registers which interrupt was triggered. While there we convert comments in structs tb_ring and tb_nhi to follow kernel-doc format more closely. This code is based on the work done by Amir Levy and Michael Jamet. Signed-off-by: Michael Jamet Signed-off-by: Mika Westerberg Reviewed-by: Yehezkel Bernat Reviewed-by: Andy Shevchenko Signed-off-by: Andreas Noever Signed-off-by: Greg Kroah-Hartman