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2021-07-27tty: drop put_tty_driverJiri Slaby
put_tty_driver() is an alias for tty_driver_kref_put(). There is no need for two exported identical functions, therefore switch all users of old put_tty_driver() to new tty_driver_kref_put() and remove the former for good. Cc: Richard Henderson <[email protected]> Cc: Ivan Kokshaysky <[email protected]> Cc: Matt Turner <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Jeff Dike <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Anton Ivanov <[email protected]> Cc: Chris Zankel <[email protected]> Cc: Max Filippov <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Samuel Iglesias Gonsalvez <[email protected]> Cc: Jens Taprogge <[email protected]> Cc: Karsten Keil <[email protected]> Cc: Scott Branden <[email protected]> Cc: Ulf Hansson <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: David Lin <[email protected]> Cc: Johan Hovold <[email protected]> Cc: Alex Elder <[email protected]> Cc: Jiri Slaby <[email protected]> Cc: Laurentiu Tudor <[email protected]> Cc: Jiri Kosina <[email protected]> Cc: David Sterba <[email protected]> Cc: Shawn Guo <[email protected]> Cc: Sascha Hauer <[email protected]> Cc: Pengutronix Kernel Team <[email protected]> Cc: Fabio Estevam <[email protected]> Cc: NXP Linux Team <[email protected]> Cc: Oliver Neukum <[email protected]> Cc: Felipe Balbi <[email protected]> Cc: Mathias Nyman <[email protected]> Cc: Marcel Holtmann <[email protected]> Cc: Johan Hedberg <[email protected]> Cc: Luiz Augusto von Dentz <[email protected]> Acked-by: Alex Elder <[email protected]> Acked-by: Christian Borntraeger <[email protected]> Acked-by: Max Filippov <[email protected]> Acked-by: David Sterba <[email protected]> Acked-by: Samuel Iglesias Gonsálvez <[email protected]> Signed-off-by: Jiri Slaby <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2021-07-27tty: make tty_set_operations an inlineJiri Slaby
Since commit f34d7a5b7010 (tty: The big operations rework) in 2008, tty_set_operations() is a simple one-line assignment. There is no reason for this to be an exported function, hence move it to a header and make an inline from that. Signed-off-by: Jiri Slaby <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2021-07-27tty: drop alloc_tty_driverJiri Slaby
Noone uses this deprecated function now. So we can remove it. Signed-off-by: Jiri Slaby <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2021-07-27tty: include kref.h in tty_driver.hJiri Slaby
We use kref in tty_driver.h, but do not include kref.h. It is currently included by linux/cdev.h -> linux/kobject.h -> linux/kref.h chain, so everything is in order only implicitly. So make this dependency explicit. Signed-off-by: Jiri Slaby <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2021-07-27tty: move tty_driver related prototypes to tty_driver.hJiri Slaby
We already have tty_driver.h, so cleanup tty.h a bit by moving out tty_driver-related function prototypes into tty_driver.h. Note that tty.h already includes tty_driver.h. Signed-off-by: Jiri Slaby <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2021-05-13tty: remove unused tty_throttleJiri Slaby
The last user was removed in commit e91e52e42814 (n_tty: Fix stuck throttled driver) in 2013. So remove exported tty_throttle completely. Signed-off-by: Jiri Slaby <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2021-05-13tty: make tty_operations::chars_in_buffer return uintJiri Slaby
tty_operations::chars_in_buffer is another hook which is expected to return values >= 0. So make it explicit by the return type too -- use unsigned int. Signed-off-by: Jiri Slaby <[email protected]> Acked-By: Anton Ivanov <[email protected]> Acked-by: David Sterba <[email protected]> Cc: Jeff Dike <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Samuel Iglesias Gonsalvez <[email protected]> Cc: Jens Taprogge <[email protected]> Cc: Karsten Keil <[email protected]> Cc: Ulf Hansson <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: David Lin <[email protected]> Cc: Johan Hovold <[email protected]> Cc: Alex Elder <[email protected]> Cc: Jiri Kosina <[email protected]> Cc: Shawn Guo <[email protected]> Cc: Sascha Hauer <[email protected]> Cc: Oliver Neukum <[email protected]> Cc: Felipe Balbi <[email protected]> Cc: Mathias Nyman <[email protected]> Cc: Marcel Holtmann <[email protected]> Cc: Johan Hedberg <[email protected]> Cc: Luiz Augusto von Dentz <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2021-05-13tty: make tty_operations::write_room return uintJiri Slaby
Line disciplines expect a positive value or zero returned from tty->ops->write_room (invoked by tty_write_room). So make this assumption explicit by using unsigned int as a return value. Both of tty->ops->write_room and tty_write_room. Signed-off-by: Jiri Slaby <[email protected]> Acked-by: Laurentiu Tudor <[email protected]> Acked-by: Alex Elder <[email protected]> Acked-by: Max Filippov <[email protected]> # xtensa Acked-by: David Sterba <[email protected]> Acked-By: Anton Ivanov <[email protected]> Acked-by: Geert Uytterhoeven <[email protected]> Cc: Richard Henderson <[email protected]> Cc: Ivan Kokshaysky <[email protected]> Cc: Matt Turner <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Helge Deller <[email protected]> Cc: Jeff Dike <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Chris Zankel <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Samuel Iglesias Gonsalvez <[email protected]> Cc: Jens Taprogge <[email protected]> Cc: Karsten Keil <[email protected]> Cc: Scott Branden <[email protected]> Cc: Ulf Hansson <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: David Lin <[email protected]> Cc: Johan Hovold <[email protected]> Cc: Jiri Kosina <[email protected]> Cc: Shawn Guo <[email protected]> Cc: Sascha Hauer <[email protected]> Cc: Oliver Neukum <[email protected]> Cc: Felipe Balbi <[email protected]> Cc: Mathias Nyman <[email protected]> Cc: Marcel Holtmann <[email protected]> Cc: Johan Hedberg <[email protected]> Cc: Luiz Augusto von Dentz <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2021-05-13tty: cumulate and document tty_struct::flow* membersJiri Slaby
Group the flow flags under a single struct called flow. The new struct contains 'stopped' and 'tco_stopped' bools which used to be bits in a bitfield. The struct also contains the lock protecting them to potentially share the same cache line. Note that commit c545b66c6922b (tty: Serialize tcflow() with other tty flow control changes) added a padding to the original bitfield. It was for the bitfield to occupy a whole 64b word to avoid interferring stores on Alpha (cannot we evaporate this arch with weird implications to C code yet?). But it doesn't work as expected as the padding (tty_struct::unused) is aligned to a 8B boundary too and occupies some bytes from the next word. So make it reliable by: 1) setting __aligned of the struct -- that aligns the start, and 2) making 'unsigned long unused[0]' as the last member of the struct -- pads the end. This is also the perfect time to start the documentation of tty_struct where all this lives. So we start by documenting what these bools actually serve for. And why we do all the alignment dances. Only the few up-to-date information from the Theodore's comment made it into this new Kerneldoc comment. Signed-off-by: Jiri Slaby <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Ulf Hansson <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Shawn Guo <[email protected]> Cc: Sascha Hauer <[email protected]> Cc: Vineet Gupta <[email protected]> Cc: "Maciej W. Rozycki" <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2021-04-10tty: fix return value for unsupported ioctlsJohan Hovold
Drivers should return -ENOTTY ("Inappropriate I/O control operation") when an ioctl isn't supported, while -EINVAL is used for invalid arguments. Fix up the TIOCMGET, TIOCMSET and TIOCGICOUNT helpers which returned -EINVAL when a tty driver did not implement the corresponding operations. Note that the TIOCMGET and TIOCMSET helpers predate git and do not get a corresponding Fixes tag below. Fixes: d281da7ff6f7 ("tty: Make tiocgicount a handler") Signed-off-by: Johan Hovold <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2020-12-04tty: Remove dead termiox codeJann Horn
set_termiox() and the TCGETX handler bail out with -EINVAL immediately if ->termiox is NULL, but there are no code paths that can set ->termiox to a non-NULL pointer; and no such code paths seem to have existed since the termiox mechanism was introduced back in commit 1d65b4a088de ("tty: Add termiox") in v2.6.28. Similarly, no driver actually implements .set_termiox; and it looks like no driver ever has. Delete this dead code; but leave the definition of struct termiox in the UAPI headers intact. Signed-off-by: Jann Horn <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2018-09-14tty_ioctl(): start taking TIOC[SG]SERIAL into separate methodsAl Viro
->set_serial() and ->get_serial() resp., both taking tty and a kernel pointer to serial_struct. Signed-off-by: Al Viro <[email protected]>
2018-05-16tty: replace ->proc_fops with ->proc_showChristoph Hellwig
Just set up the show callback in the tty_operations, and use proc_create_single_data to create the file without additional boilerplace code. Signed-off-by: Christoph Hellwig <[email protected]>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
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 <[email protected]> Reviewed-by: Philippe Ombredanne <[email protected]> Reviewed-by: Thomas Gleixner <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-08-28pty: show associative slave of ptmx in fdinfoMasatake YAMATO
This patch adds "tty-index" field to /proc/PID/fdinfo/N if N specifies /dev/ptmx. The field shows the index of associative slave pts. Though a minor number is given for each pts instance, ptmx is not. It means there is no way in user-space to know the association between file descriptors for pts/n and ptmx. (n = 0, 1, ...) This is different from pipe. About pipe such association can be solved by inode of pipefs. Providing the way to know the association between pts/n and ptmx helps users understand the status of running system. lsof can utilize this field. Signed-off-by: Masatake YAMATO <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-06-30randstruct: Mark various structs for randomizationKees Cook
This marks many critical kernel structures for randomization. These are structures that have been targeted in the past in security exploits, or contain functions pointers, pointers to function pointer tables, lists, workqueues, ref-counters, credentials, permissions, or are otherwise sensitive. This initial list was extracted from Brad Spengler/PaX Team's code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Left out of this list is task_struct, which requires special handling and will be covered in a subsequent patch. Signed-off-by: Kees Cook <[email protected]>
2016-04-26devpts: more pty driver interface cleanupsLinus Torvalds
This is more prep-work for the upcoming pty changes. Still just code cleanup with no actual semantic changes. This removes a bunch pointless complexity by just having the slave pty side remember the dentry associated with the devpts slave rather than the inode. That allows us to remove all the "look up the dentry" code for when we want to remove it again. Together with moving the tty pointer from "inode->i_private" to "dentry->d_fsdata" and getting rid of pointless inode locking, this removes about 30 lines of code. Not only is the end result smaller, it's simpler and easier to understand. The old code, for example, depended on the d_find_alias() to not just find the dentry, but also to check that it is still hashed, which in turn validated the tty pointer in the inode. That is a _very_ roundabout way to say "invalidate the cached tty pointer when the dentry is removed". The new code just does dentry->d_fsdata = NULL; in devpts_pty_kill() instead, invalidating the tty pointer rather more directly and obviously. Don't do something complex and subtle when the obvious straightforward approach will do. The rest of the patch (ie apart from code deletion and the above tty pointer clearing) is just switching the calling convention to pass the dentry or file pointer around instead of the inode. Cc: Eric Biederman <[email protected]> Cc: Peter Anvin <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Al Viro <[email protected]> Cc: Peter Hurley <[email protected]> Cc: Serge Hallyn <[email protected]> Cc: Willy Tarreau <[email protected]> Cc: Aurelien Jarno <[email protected]> Cc: Alan Cox <[email protected]> Cc: Jann Horn <[email protected]> Cc: Greg KH <[email protected]> Cc: Jiri Slaby <[email protected]> Cc: Florian Weimer <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2015-08-03Avoid usb reset crashes by making tty_io cdevs truly dynamicRichard Watts
Avoid usb reset crashes by making tty_io cdevs truly dynamic Signed-off-by: Richard Watts <[email protected]> Reported-by: Duncan Mackintosh <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2014-09-23tty: Serialize tty flow control changes with flow_lockPeter Hurley
Without serialization, the flow control state can become inverted wrt. the actual hardware state. For example, CPU 0 | CPU 1 stop_tty() | lock ctrl_lock | tty->stopped = 1 | unlock ctrl_lock | | start_tty() | lock ctrl_lock | tty->stopped = 0 | unlock ctrl_lock | driver->start() driver->stop() | In this case, the flow control state now indicates the tty has been started, but the actual hardware state has actually been stopped. Introduce tty->flow_lock spinlock to serialize tty flow control changes. Split out unlocked __start_tty()/__stop_tty() flavors for use by ioctl(TCXONC) in follow-on patch. Signed-off-by: Peter Hurley <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2014-07-10tty: Document locking for tty driver methodsPeter Hurley
The tty core calls the tty driver's open, close and hangup methods holding the tty lock. Signed-off-by: Peter Hurley <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2013-02-04tty: Document required behavior of tty driver close()Peter Hurley
If the tty driver open() fails, the tty driver close() is still called during the resultant tty release. Signed-off-by: Peter Hurley <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2012-08-13TTY: move cdev_add to tty_register_deviceJiri Slaby
We need the /dev/ node not to be available before we call tty_register_device. Otherwise we might race with open and tty_struct->port might not be available at that time. This is not an issue now, but would be a problem after "TTY: use tty_port_register_device" is applied. Signed-off-by: Jiri Slaby <[email protected]> Acked-by: Alan Cox <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2012-08-13TTY: add support for unnumbered device nodesJiri Slaby
This allows drivers like ttyprintk to avoid hacks to create an unnumbered node in /dev. It used to set TTY_DRIVER_DYNAMIC_DEV in flags and call device_create on its own. That is incorrect, because TTY_DRIVER_DYNAMIC_DEV may be set only if tty_register_device is called explicitly. Signed-off-by: Jiri Slaby <[email protected]> Acked-by: Alan Cox <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2012-08-13TTY: pty, switch to tty_alloc_driverJiri Slaby
Switch to the new driver allocation interface, as this is one of the special call-sites. Here, we need TTY_DRIVER_DYNAMIC_ALLOC to not allocate tty_driver->ports, cdevs and potentially other structures because we reserve too many lines in pty. Instead, it provides the tty_port<->tty_struct link in tty->ops->install already. Signed-off-by: Jiri Slaby <[email protected]> Acked-by: Alan Cox <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2012-08-10TTY: pass flags to alloc_tty_driverJiri Slaby
We need to allow drivers that use neither tty_port_install nor tty_port_register_device to link a tty_port to a tty somehow. To avoid a race with open, this has to be performed before tty_register_device. But currently tty_driver->ports is allocated even in tty_register_device because we do not know whether this is the PTY driver. The PTY driver is special here due to an excessive count of lines it declares to handle. We cannot handle tty_ports there this way. To circumvent this, we start passing tty_driver flags to alloc_tty_driver already and we create tty_alloc_driver for this purpose. There we can allocate tty_driver->ports and do all the magic between tty_alloc_driver and tty_register_device. Later we will introduce tty_port_link_device function for that purpose. All drivers should eventually switch to this new tty driver allocation interface. Signed-off-by: Jiri Slaby <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2012-07-17tty: Move the handling of the tty release logicAlan Cox
Now that we don't have tty->termios tied to drivers->tty we can untangle the logic here. In addition we can push the removal logic out of the destructor path. At that point we can think about sorting out tty_port and console and all the other ugly hangovers. Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2012-06-13TTY: add ports array to tty_driverJiri Slaby
It will hold tty_port structures for all drivers which do not want to define tty->ops->install hook. We ignore PTY here because it wants 1 million lines and it installs tty_port in ->install anyway. Signed-off-by: Jiri Slaby <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2012-03-08TTY: tty_driver, document tty->ops->shutdown limitationJiri Slaby
Note that tty->ops->shutdown is called from whatever context the user drops the last tty reference from. E.g. if one takes a reference in an ISR, tty close happens on other CPU and the final tty put is from the ISR, tty->ops->shutdown will be called from that hard irq context. We would have a problem in vt if we start using tty refcounting from other contexts than user there. It is because vt's shutdown uses mutexes. This is yet to be fixed. Signed-off-by: Jiri Slaby <[email protected]> Reported-by: Al Viro <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2012-03-08TTY: remove minor_num from tty_driverJiri Slaby
It was added back in 2004 and never used for anything real. Remove the only assignment in the tree as well. Signed-off-by: Jiri Slaby <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2012-03-08TTY: let alloc_tty_driver deduce the owner automaticallyJiri Slaby
Like the rest of the kernel, make a stub from alloc_tty_driver which calls __alloc_tty_driver with proper owner. This will save us one more assignment on the driver side. Also this fixes some drivers which didn't set the owner. This allowed user to remove the module from the system even though a tty from the driver is still open. Signed-off-by: Jiri Slaby <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2012-01-17tty: remove unused tty_driver->termios_lockedKonstantin Khlebnikov
This field is unused since 2.6.28 (commit fe6e29fdb1a7: "tty: simplify ktermios allocation", to be exact) Signed-off-by: Konstantin Khlebnikov <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2011-08-23TTY: pty, fix pty countingJiri Slaby
tty_operations->remove is normally called like: queue_release_one_tty ->tty_shutdown ->tty_driver_remove_tty ->tty_operations->remove However tty_shutdown() is called from queue_release_one_tty() only if tty_operations->shutdown is NULL. But for pty, it is not. pty_unix98_shutdown() is used there as ->shutdown. So tty_operations->remove of pty (i.e. pty_unix98_remove()) is never called. This results in invalid pty_count. I.e. what can be seen in /proc/sys/kernel/pty/nr. I see this was already reported at: https://lkml.org/lkml/2009/11/5/370 But it was not fixed since then. This patch is kind of a hackish way. The problem lies in ->install. We allocate there another tty (so-called tty->link). So ->install is called once, but ->remove twice, for both tty and tty->link. The fix here is to count both tty and tty->link and divide the count by 2 for user. And to have ->remove called, let's make tty_driver_remove_tty() global and call that from pty_unix98_shutdown() (tty_operations->shutdown). While at it, let's document that when ->shutdown is defined, tty_shutdown() is not called. Signed-off-by: Jiri Slaby <[email protected]> Cc: Alan Cox <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: stable <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2011-02-17tty: now phase out the ioctl file pointer for goodAlan Cox
Only oddities here are a couple of drivers that bogusly called the ldisc helpers instead of returning -ENOIOCTLCMD. Fix the bug and the rest goes away. Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2011-02-17tiocmset: kill the file pointer argumentAlan Cox
Doing tiocmget was such fun we should do tiocmset as well for the same reasons Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2011-02-17tiocmget: kill off the passing of the struct fileAlan Cox
We don't actually need this and it causes problems for internal use of this functionality. Currently there is a single use of the FILE * pointer. That is the serial core which uses it to check tty_hung_up_p. However if that is true then IO_ERROR is also already set so the check may be removed. Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2010-12-16tty: fix typos/errors in tty_driver.h commentsTimur Tabi
Fix various typos and other errors in comments of tty_driver.h. The most significant is the wrong name of a function for the description of TTY_DRIVER_DYNAMIC_DEV. Signed-off-by: Timur Tabi <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2010-11-16TTY: include termios.h in tty_driver.hJiri Slaby
We reference termios and termiox in tty_driver.h, but we do not include linux/termios.h where these are defined. Add the #include properly. Otherwise when we include tty_driver.h, we get compile errors. Signed-off-by: Jiri Slaby <[email protected]> Cc: Alan Cox <[email protected]> Cc: Greg KH <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2010-10-22tty: Make tiocgicount a handlerAlan Cox
Dan Rosenberg noted that various drivers return the struct with uncleared fields. Instead of spending forever trying to stomp all the drivers that get it wrong (and every new driver) do the job in one place. This first patch adds the needed operations and hooks them up, including the needed USB midlayer and serial core plumbing. Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2009-09-27tty: Fix regressions caused by commit b50989dcDave Young
The following commit made console open fails while booting: commit b50989dc444599c8b21edc23536fc305f4e9b7d5 Author: Alan Cox <[email protected]> Date: Sat Sep 19 13:13:22 2009 -0700 tty: make the kref destructor occur asynchronously Due to tty release routines run in a workqueue now, error like the following will be reported while booting: INIT open /dev/console Input/output error It also causes hibernation regression to appear as reported at http://bugzilla.kernel.org/show_bug.cgi?id=14229 The reason is that now there's latency issue with closing, but when we open a "closing not finished" tty, -EIO will be returned. Fix it as per the following Alan's suggestion: Fun but it's actually not a bug and the fix is wrong in itself as the port may be closing but not yet being destructed, in which case it seems to do the wrong thing. Opening a tty that is closing (and could be closing for long periods) is supposed to return -EIO. I suspect a better way to deal with this and keep the old console timing is to split tty->shutdown into two functions. tty->shutdown() - called synchronously just before we dump the tty onto the waitqueue for destruction tty->cleanup() - called when the destructor runs. We would then do the shutdown part which can occur in IRQ context fine, before queueing the rest of the release (from tty->magic = 0 ... the end) to occur asynchronously The USB update in -next would then need a call like if (tty->cleanup) tty->cleanup(tty); at the top of the async function and the USB shutdown to be split between shutdown and cleanup as the USB resource cleanup and final tidy cannot occur synchronously as it needs to sleep. In other words the logic becomes final kref put make object unfindable async clean it up Signed-off-by: Dave Young <[email protected]> [ rjw: Rebased on top of 2.6.31-git, reworked the changelog. ] Signed-off-by: "Rafael J. Wysocki" <[email protected]> [ Changed serial naming to match new rules, dropped tty_shutdown as per comments from Alan Stern - Linus ] Signed-off-by: Linus Torvalds <[email protected]>
2009-06-11tty: throttling race fixAlan Cox
The tty throttling code can race due to the lock drops. It takes very high loads but this has been observed and verified by Rob Duncan. The basic problem is that on an SMP box we can go CPU #1 CPU #2 need to throttle ? suppose we should buffer space cleared are we throttled yes ? - unthrottle call throttle method This changeet take the termios lock to protect against this. The termios lock isn't the initial obvious candidate but many implementations of throttle methods already need to poke around their own termios structures (and nobody really locks them against a racing change of flow control). This does mean that anyone who is setting tty->low_latency = 1 and then calling tty_flip_buffer_push from their unthrottle method is going to end up collapsing in a pile of locks. However we've removed all the known bogus users of low_latency = 1 and such use isn't safe anyway for other reasons so catching it would be an improvement. Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2009-04-07tty: Correct inline types for tty_driver_kref_get()Adrian Bunk
tty_driver_kref_get() should be static inline and not extern inline (the latter even changed it's semantics in gcc >= 4.3). Signed-off-by: Adrian Bunk <[email protected]> Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2009-04-01proc tty: remove struct tty_operations::read_procAlexey Dobriyan
struct tty_operations::proc_fops took it's place and there is one less create_proc_read_entry() user now! Signed-off-by: Alexey Dobriyan <[email protected]> Cc: Alan Cox <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2009-04-01proc tty: add struct tty_operations::proc_fopsAlexey Dobriyan
Used for gradual switch of TTY drivers from using ->read_proc which helps with gradual switch from ->read_proc for the whole tree. As side effect, fix possible race condition when ->data initialized after PDE is hooked into proc tree. ->proc_fops takes precedence over ->read_proc. Signed-off-by: Alexey Dobriyan <[email protected]> Cc: Alan Cox <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2009-01-02pty: simplify resizeAlan Cox
We have special case logic for resizing pty/tty pairs. We also have a per driver resize method so for the pty case we should use it. Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2008-10-13Add an instance parameter devpts interfacesSukadev Bhattiprolu
Pass-in 'inode' or 'tty' parameter to devpts interfaces. With multiple devpts instances, these parameters will be used in subsequent patches to identify the instance of devpts mounted. The parameters also help simplify devpts implementation. Changelog[v3]: - minor changes due to merge with ttydev updates - rename parameters to emphasize they are ptmx or pts inodes - pass-in tty_struct * to devpts_pty_kill() (this will help cleanup the get_node() call in a subsequent patch) Signed-off-by: Sukadev Bhattiprolu <[email protected]> Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2008-10-13tty: More driver operationsAlan Cox
We have the lookup operation abstracted which is nice for pty cleanup but we really want to abstract the add/remove entries as well so that we can pull the pty code out of the tty core and create a clear defined interface for the tty driver table. Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2008-10-13tty: kref the tty driver objectAlan Cox
Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2008-10-13tty: Clean up the tty_init_dev changes furtherAlan Cox
Fix up the naming, style and extract some bits of code into the driver specific code Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2008-10-13tty: shutdown methodAlan Cox
Right now there are various drivers that try to use tty->count to know when they get the final close. Aristeau Rozanski showed while debugging the vt sysfs race that this isn't entirely safe. Instead of driver side tricks to work around this introduce a shutdown which is called when the tty is being destructed. This also means that the shutdown method is tied into the refcounting. Use this to rework the console close/sysfs logic. Remove lots of special case code from the tty core code. The pty code can now have a shutdown() method that replaces the special case hackery in the tree free up paths. Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2008-10-13tty: Add termioxAlan Cox
We need a way to describe the various additional modes and flow control features that random weird hardware shows up and software such as wine wants to emulate as Windows supports them. TCGETX/TCSETX and the termiox ioctl are a SYS5 extension that we might as well adopt. This patches adds the structures and the basic ioctl interfaces when the TCGETX etc defines are added for an architecture. Drivers wishing to use this stuff need to add new methods. Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>