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path: root/drivers/tty/tty_io.c
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2017-04-18tty: split job control support into a file of its ownNicolas Pitre
This makes it easier for job control to become optional and/or usable independently from tty_io.c, as well as providing a nice purpose separation. No logical changes from this patch. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-18console: move console_init() out of tty_io.cNicolas Pitre
All the console driver handling code lives in printk.c. Move console_init() there as well so console support can still be used when the TTY code is configured out. No logical changes from this patch. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08tty: fix comment typo s/repsonsible/responsible/Thadeu Lima de Souza Cascardo
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@cascardo.eti.br> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-31tty: reset termios state on device registrationJohan Hovold
Free any saved termios data when registering a tty device so that the termios state is reset when reusing a minor number. This is useful for hot-pluggable buses such as USB where it does not make much sense to reuse saved termios data from an unrelated device when a new device is later plugged in. This specifically avoids a situation where the new device does not have the carrier-detect signal wired, but the saved termios state has CLOCAL cleared, effectively preventing the port from being opened in blocking mode as noted by Jan Kundrát <jan.kundrat@cesnet.cz>. Note that clearing the saved data at deregistration would not work as the device could still be open. Also note that the termios data is not reset for drivers with TTY_DRIVER_DYNAMIC_ALLOC set (e.g. legacy pty) as their character device is registered at driver registration and could theoretically already have been opened (and pty termios state is never saved anyway). Reported-by: Jan Kundrát <jan.kundrat@cesnet.cz> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-31tty: drop obsolete termios_locked commentsJohan Hovold
Drop comments about tty-driver termios_locked structures, which have been outdated since commit fe6e29fdb1a7 ("tty: simplify ktermios allocation"). Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-31tty: close race between device register and openJohan Hovold
The tty class device is currently not registered until after the character device has been registered thereby leaving a small window were a racing open could end up with a NULL tty->dev pointer due to the class-device lookup failing in alloc_tty_struct. Close this race by registering the class device before the character device while making sure to defer the user-space uevent notification until after the character device has been registered. Note that some tty drivers expect a valid tty->dev and would misbehave or crash otherwise. Some line disciplines also currently dereference the class device unconditionally despite the fact that not every tty is guaranteed to have one (Unix98 pty), but this is being fixed separately. Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-17drivers/tty: Convert remaining uses of pr_warning to pr_warnJoe Perches
To enable eventual removal of pr_warning This makes pr_warn use consistent for drivers/tty Prior to this patch, there were 2 uses of pr_warning and 23 uses of pr_warn in drivers/tty Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/task.h> We are going to split <linux/sched/task.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/signal.h> We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/signal.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-19tty_port: allow a port to be opened with a tty that has no file handleAlan Cox
Let us create tty objects entirely in kernel space. Untested proposal to show why all the ideas around rewriting half the uart stack are not needed. With this a kernel created non file backed tty object could be used to handle data, and set terminal modes. Not all ldiscs can cope with this as N_TTY in particular has to work back to the fs/tty layer. The tty_port code is however otherwise clean of file handles as far as I can tell as is the low level tty port write path used by the ldisc, the configuration low level interfaces and most of the ldiscs. Currently you don't have any exposure to see tty hangups because those are built around the file layer. However a) it's a fixed port so you probably don't care about that b) if you do we can add a callback and c) you almost certainly don't want the userspace tear down/rebuild behaviour anyway. This should however be sufficient if we wanted for example to enumerate all the bluetooth bound fixed ports via ACPI and make them directly available. It doesn't deal with the case of a user opening a port that's also kernel opened and that would need some locking out (so it returned EBUSY if bound to a kernel device of some kind). That needs resolving along with how you "up" or "down" your new bluetooth device, or enumerate it while providing the existing tty API to avoid regressions (and to debug). Signed-off-by: Alan Cox <alan@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-By: Sebastian Reichel <sre@kernel.org> Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19tty: move the non-file related parts of tty_release to new tty_release_structRob Herring
For in-kernel tty users, we need to be able to create and destroy 'struct tty' that are not associated with a file. The creation side is fine, but tty_release() needs to be split into the file handle portion and the struct tty portion. Introduce a new function, tty_release_struct, to handle just the destroying of a struct tty. Signed-off-by: Rob Herring <robh@kernel.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-By: Sebastian Reichel <sre@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-09Merge 4.6-rc7 into tty-nextGreg Kroah-Hartman
We want the pty fixes in here as well so that patches can build on it. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30tty: Remove stale parameter commentPeter Hurley
noctty was removed as a parameter by commit 11e1d4aa4da ("tty: Consolidate noctty check in tty_open()"). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30tty: Remove unused TTY_NUMBER() macroPeter Hurley
TTY_NUMBER() has been unused since v2.5.71; removed by "[PATCH] callout removal: callout is gone". Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30tty: Replace TTY_IO_ERROR bit tests with tty_io_error()Peter Hurley
Abstract TTY_IO_ERROR status test treewide with tty_io_error(). NB: tty->flags uses atomic bit ops; replace non-atomic bit test with test_bit(). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-31tty: Fix merge of "tty: Refactor tty_open()"Peter Hurley
Commit e9036d066236 ("tty: Drop krefs for interrupted tty lock") fixed a tty reference counting problem introduced in commit 0bfd464d3fdd ("tty: Wait interruptibly for tty lock on reopen"), so v4.5.0 is correct. However, commit d6203d0c7b73 ("tty: Refactor tty_open()") moved the relevant code for 4.6-rc1; correct the merge. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-31tty: Fix UML console breakagePeter Hurley
User-Mode Linux supplies an alternate TTY_MAJOR driver for stdio console, so the noctty check in tty_open() must apply only to VT driver tty0 devnode and not the UML console driver tty0 devnode. Fixes: 11e1d4aa4da1 ("tty: Consolidate noctty checks in tty_open()") Reported-by: Richard Weinberger <richard.weinberger@gmail.com> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-28tty: Fix ioctl(FIOASYNC) on hungup filePeter Hurley
A small race window exists which allows signal-driven async i/o to be enabled for the tty when the file ptr has already been hungup and signal-driven i/o has been disabled: CPU 0 CPU 1 ----- ------ ioctl_fioasync(on) filp->f_op->fasync(on) __tty_hangup() tty_fasync(on) tty_lock() tty_lock() ... . filp->f_op = &hung_up_tty_fops; (waiting) __tty_fasync(off) . tty_unlock() /* gets tty lock */ /* enables FASYNC */ Check the tty has not been hungup while holding tty_lock. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-28tty: Add fasync() hung up file operationPeter Hurley
VFS uses a two-stage check-and-call method for invoking file_operations methods, without explicitly snapshotting either the file_operations ptr or the function ptr. Since the tty core is one of the few VFS users that changes the f_op file_operations ptr of the file descriptor (when the tty has been hung up), and since the likelihood of the compiler generating a reload of either f_op or the function ptr is basically nil, just define a hung up fasync() file operation that returns an error. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-28tty, n_tty: Remove fasync() ldisc notificationPeter Hurley
Only the N_TTY line discipline implements the signal-driven i/o notification enabled/disabled by fcntl(F_SETFL, O_ASYNC). The ldisc fasync() notification is sent to the ldisc when the enable state has changed (the tty core is notified via the fasync() VFS file operation). The N_TTY line discipline used the enable state to change the wakeup condition (minimum_to_wake = 1) for notifying the signal handler i/o is available. However, just the presence of data is sufficient and necessary to signal i/o is available, so changing minimum_to_wake is unnecessary (and creates a race condition with read() and poll() which may be concurrently updating minimum_to_wake). Furthermore, since the kill_fasync() VFS helper performs no action if the fasync list is empty, calling unconditionally is preferred; if signal driven i/o just has been disabled, no signal will be sent by kill_fasync() anyway so notification of the change via the ldisc fasync() method is superfluous. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Make tty_files_lock per-ttyPeter Hurley
Access to tty->tty_files list is always per-tty, never for all ttys simultaneously. Replace global tty_files_lock spinlock with per-tty ->files_lock. Initialize when the ->tty_files list is inited, in alloc_tty_struct(). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Move tty_check_change() helperPeter Hurley
Move is_ignored() to drivers/tty/tty_io.c and re-declare in file scope. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Eliminate global symbol tty_ldisc_N_TTYPeter Hurley
Reduce global tty symbols; move and rename tty_ldisc_begin() as n_tty_init() and redefine the N_TTY ldisc ops as file scope. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Unexport system-wide tty_mutexPeter Hurley
tty_mutex is a core, system-wide lock; there is no reason for any code outside the tty core to have direct access. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Document c_line == N_TTY initial conditionPeter Hurley
The line discipline id is stored in the tty's termios; document the implicit initial value of N_TTY. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Destroy ldisc instance on hangupPeter Hurley
Currently, when the tty is hungup, the ldisc is re-instanced; ie., the current instance is destroyed and a new instance is created. The purpose of this design was to guarantee a valid, open ldisc for the lifetime of the tty. However, now that tty buffers are owned by and have lifetime equivalent to the tty_port (since v3.10), any data received immediately after the ldisc is re-instanced may cause continued driver i/o operations concurrently with the driver's hangup() operation. For drivers that shutdown h/w on hangup, this is unexpected and usually bad. For example, the serial core may free the xmit buffer page concurrently with an in-progress write() operation (triggered by echo). With the existing stable and robust ldisc reference handling, the cleaned-up tty_reopen(), the straggling unsafe ldisc use cleaned up, and the preparation to properly handle a NULL tty->ldisc, the ldisc instance can be destroyed and only re-instanced when the tty is re-opened. If the tty was opened as /dev/console or /dev/tty0, the original behavior of re-instancing the ldisc is retained (the 'reinit' parameter to tty_ldisc_hangup() is true). This is required since those file descriptors are never hungup. This patch has neglible impact on userspace; the tty file_operations ptr is changed to point to the hungup file operations _before_ the ldisc instance is destroyed, so only racing file operations might now retrieve a NULL ldisc reference (which is simply handled as if the hungup file operation had been called instead -- see "tty: Prepare for destroying line discipline on hangup"). This resolves a long-standing FIXME and several crash reports. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Use 'disc' for line discipline index namePeter Hurley
tty->ldisc is a ptr to struct tty_ldisc, but unfortunately 'ldisc' is also used as a parameter or local name to refer to the line discipline index value (ie, N_TTY, N_GSM, etc.); instead prefer the name used by the line discipline registration/ref counting functions. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Prepare for destroying line discipline on hangupPeter Hurley
tty file_operations (read/write/ioctl) wait for the ldisc reference indefinitely (until ldisc lifetime events, such as hangup or TIOCSETD, finish). Since hangup now destroys the ldisc and does not instance another copy, file_operations must now be prepared to receive a NULL ldisc reference from tty_ldisc_ref_wait(): CPU 0 CPU 1 ----- ----- (*f_op->read)() => tty_read() __tty_hangup() ... f_op = &hung_up_tty_fops; ... tty_ldisc_hangup() tty_ldisc_lock() tty_ldisc_kill() tty->ldisc = NULL tty_ldisc_unlock() ld = tty_ldisc_ref_wait() /* ld == NULL */ Instead, the action taken now is to return the same value as if the tty had been hungup a moment earlier: CPU 0 CPU 1 ----- ----- __tty_hangup() ... f_op = &hung_up_tty_fops; (*f_op->read)() => hung_up_tty_read() return 0; ... tty_ldisc_hangup() tty_ldisc_lock() tty_ldisc_kill() tty->ldisc = NULL tty_ldisc_unlock() Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Reset c_line from driver's init_termiosPeter Hurley
After the ldisc is released, but before the tty is destroyed, the termios is saved (in tty_free_termios()); this termios is restored if a new tty is created on next open(). However, the line discipline is always reset, which is not obvious in the current method. Instead, reset as part of the restore. Restore the original line discipline, which may not have been N_TTY. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Refactor tty_open()Peter Hurley
Extract the driver lookup and reopen-or-initialize logic into helper function tty_open_by_driver(). No functional change. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Consolidate noctty checks in tty_open()Peter Hurley
Evaluate the conditions which prevent this tty being the controlling terminal in one place, just before setting the controlling terminal. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Re-declare tty_driver_remove_tty() file scopePeter Hurley
tty_driver_remove_tty() is only local-scope; declare as static. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Fix tty_init_termios() declarationPeter Hurley
tty_init_termios() never returns an error; re-declare as void. Remove unnecessary error handling from callers. Remove extern declarations of tty_free_termios() and free_tty_struct() and re-declare in file scope. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Acked-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Remove !tty check from free_tty_struct()Peter Hurley
free_tty_struct() is never called with NULL tty; the two call sites would already have faulted on earlier access. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-27tty: Fix ldisc leak in failed tty_init_dev()Peter Hurley
release_tty() leaks the ldisc instance when called directly (rather than when releasing the file descriptor from tty_release()). Since tty_ldisc_release() clears tty->ldisc, releasing the ldisc instance at tty teardown if tty->ldisc is non-null is not in danger of double-releasing the ldisc. Remove deinitialize_tty_struct() now that free_tty_struct() always performs the tty_ldisc_deinit(). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-26tty: Fix unsafe ldisc reference via ioctl(TIOCGETD)Peter Hurley
ioctl(TIOCGETD) retrieves the line discipline id directly from the ldisc because the line discipline id (c_line) in termios is untrustworthy; userspace may have set termios via ioctl(TCSETS*) without actually changing the line discipline via ioctl(TIOCSETD). However, directly accessing the current ldisc via tty->ldisc is unsafe; the ldisc ptr dereferenced may be stale if the line discipline is changing via ioctl(TIOCSETD) or hangup. Wait for the line discipline reference (just like read() or write()) to retrieve the "current" line discipline id. Cc: <stable@vger.kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-26tty: Retry failed reopen if tty teardown in-progressPeter Hurley
A small window exists where a tty reopen will observe the tty just prior to imminent teardown (tty->count == 0); in this case, open() returns EIO to userspace. Instead, retry the open after checking for signals and yielding; this interruptible retry loop allows teardown to commence and initialize a new tty on retry. Never retry the BSD master pty reopen; there is no guarantee the pty pair teardown is imminent since the slave file descriptors may remain open indefinitely. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Cc: stable <stable@vger.kernel.org> # 4.4 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-26tty: Wait interruptibly for tty lock on reopenPeter Hurley
Allow a signal to interrupt the wait for a tty reopen; eg., if the tty has starting final close and is waiting for the device to drain. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Cc: stable <stable@vger.kernel.org> # 4.4 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13tty: Only allow slave pty as controlling ttyPeter Hurley
A master pty should never be a controlling tty in Linux; if the master pty is specified to ioctl(TIOCSCTTY), silently substitute the slave pty as the controlling tty. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13tty: core: Prefer dev_dbg() over pr_debug()Peter Hurley
Where possible, use dev_dbg() instead of pr_debug() Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13tty: Remove __func__ from tty_debug() macroPeter Hurley
Now that tty_debug() macro uses pr_debug(), the function name can be printed when using dynamic debug; printing the function name within the format string is redundant. Remove the __func__ parameter and print specifier from the format string. Add context to messages for when the function name is not printed by dynamic debug, or when dynamic debug is not enabled. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13tty: core: Prefer pr_* to printk(*)Peter Hurley
Convert remaining printk() use to pr_*() when tty is unknown or unsafe to use. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13tty: core: Add driver name to invalid device registration messagePeter Hurley
Include the driver name in the tty_register_device_attr() error message for invalid index. Note that tty_err() cannot be used here because there is no tty; use pr_err(). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13tty: Convert SAK messages to tty_notice()Peter Hurley
Use tty_notice() for unified message format from the tty core. Fix each message to accurately reflect the cause of each termination. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13tty: Define tty_*() printk macrosPeter Hurley
Since not all ttys are devices (eg., SysV ptys), dev_*() printk macros cannot be used. Define tty_*() printk macros that output in similar format to dev_*() macros (ie., <driver> <tty>: .....). Transform the most-trivial printk( LEVEL ...) usage to tty_*() usage. NB: The function name has been eliminated from messages with unique context, or prefixed to the format when given. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13tty: core: Add helper fn to deref tty driver namePeter Hurley
Similar to tty_name(), add tty_driver_name() helper to safely dereference tty->driver->name (otherwise return empty string). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13tty: core: Remove redundant oom messagePeter Hurley
kmalloc() already emits a diagnostic for failed allocations; remove tty-specific message. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13tty: Make tty_paranoia_check() file scopePeter Hurley
tty_paranoia_check() is only used within drivers/tty/tty_io.c; remove extern declaration in header and limit symbol to file scope. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-20tty: Fix tty_send_xchar() lock order inversionPeter Hurley
The correct lock order is atomic_write_lock => termios_rwsem, as established by tty_write() => n_tty_write(). Fixes: c274f6ef1c666 ("tty: Hold termios_rwsem for tcflow(TCIxxx)") Reported-and-Tested-by: Dmitry Vyukov <dvyukov@google.com> Cc: <stable@vger.kernel.org> # v3.18+ Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>