28 Sep, 2009
1 commit
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The following commit made console open fails while booting:
commit b50989dc444599c8b21edc23536fc305f4e9b7d5
Author: Alan Cox
Date: Sat Sep 19 13:13:22 2009 -0700tty: 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=14229The 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 destructiontty->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 asynchronouslyThe 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 unfindableasync
clean it upSigned-off-by: Dave Young
[ rjw: Rebased on top of 2.6.31-git, reworked the changelog. ]
Signed-off-by: "Rafael J. Wysocki"
[ Changed serial naming to match new rules, dropped tty_shutdown as per
comments from Alan Stern - Linus ]
Signed-off-by: Linus Torvalds
11 Jun, 2009
1 commit
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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 methodThis 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
Signed-off-by: Linus Torvalds
07 Apr, 2009
1 commit
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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
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds
01 Apr, 2009
2 commits
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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
Cc: Alan Cox
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
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
Cc: Alan Cox
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
03 Jan, 2009
1 commit
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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
Signed-off-by: Linus Torvalds
14 Oct, 2008
6 commits
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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
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
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
Signed-off-by: Linus Torvalds -
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
Fix up the naming, style and extract some bits of code into the driver
specific codeSigned-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
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
Signed-off-by: Linus Torvalds -
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
Signed-off-by: Linus Torvalds
16 Aug, 2008
1 commit
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This moves it to being a tty operation. That removes special cases and now
also means that resize can be picked up by um and other non vt consoles
which may have a resize operation.Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds
23 Jul, 2008
1 commit
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Some hardware needs to do break handling itself and may have partial
support only. Make break_ctl return an error code. Add a tty driver flag
so you can indicate driver hardware side break support.Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds
24 Jun, 2008
1 commit
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Some of the requirement rules are now more relaxed. Also correct a
contradiction in the previous updateSigned-off-by: Alan Cox
Signed-off-by: Linus Torvalds
30 Apr, 2008
2 commits
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Something Arjan suggested which allows us to clean up the code nicely
Signed-off-by: Alan Cox
Cc: Arjan van de Ven
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
- Operations are now a shared const function block as with most other Linux
objects- Introduce wrappers for some optional functions to get consistent behaviour
- Wrap put_char which used to be patched by the tty layer
- Document which functions are needed/optional
- Make put_char report success/fail
- Cache the driver->ops pointer in the tty as tty->ops
- Remove various surplus lock calls we no longer need
- Remove proc_write method as noted by Alexey Dobriyan
- Introduce some missing sanity checks where certain driver/ldisc
combinations would oops as they didn't check needed methods were present[akpm@linux-foundation.org: fix fs/compat_ioctl.c build]
[akpm@linux-foundation.org: fix isicom]
[akpm@linux-foundation.org: fix arch/ia64/hp/sim/simserial.c build]
[akpm@linux-foundation.org: fix kgdb]
Signed-off-by: Alan Cox
Acked-by: Greg Kroah-Hartman
Cc: Jason Wessel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
18 Apr, 2008
1 commit
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polled console handling support, to access a console in an irq-less
way while in debug or irq context.absolutely zero impact as long as CONFIG_CONSOLE_POLL is disabled.
(which is the default)[ jan.kiszka@siemens.com: lots of cleanups ]
[ mingo@elte.hu: redesign, splitups, cleanups. ]Signed-off-by: Jason Wessel
Signed-off-by: Ingo Molnar
Signed-off-by: Jan Kiszka
Reviewed-by: Thomas Gleixner
11 May, 2007
1 commit
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Add compat_ioctl method for tty code to allow processing of 32 bit ioctl
calls on 64 bit systems by tty core, tty drivers, and line disciplines.Based on patch by Arnd Bergmann:
http://www.uwsg.iu.edu/hypermail/linux/kernel/0511.0/1732.html[akpm@linux-foundation.org: make things static]
Signed-off-by: Paul Fulghum
Acked-by: Arnd Bergmann
Cc: Alan Cox
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
09 Dec, 2006
1 commit
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This is the core of the switch to the new framework. I've split it from the
driver patches which are mostly search/replace and would encourage people to
give this one a good hard stare.The references to BOTHER and ISHIFT are the termios values that must be
defined by a platform once it wants to turn on "new style" ioctl support. The
code patches here ensure that providing1. The termios overlays the ktermios in memory
2. The only new kernel only fields are c_ispeed/c_ospeed (or none)the existing behaviour is retained. This is true for the patches at this
point in time.Future patches will define BOTHER, ISHIFT and enable newer termios structures
for each architecture, and once they are all done some of the ifdefs also
vanish.[akpm@osdl.org: warning fix]
[akpm@osdl.org: IRDA fix]
Signed-off-by: Alan Cox
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
02 Oct, 2006
1 commit
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As part of an SMP cleanliness pass over UML, I consted a bunch of
structures in order to not have to document their locking. One of these
structures was a struct tty_operations. In order to const it in UML
without introducing compiler complaints, the declaration of
tty_set_operations needs to be changed, and then all of its callers need to
be fixed.This patch declares all struct tty_operations in the tree as const. In all
cases, they are static and used only as input to tty_set_operations. As an
extra check, I ran an i386 allyesconfig build which produced no extra
warnings.53 drivers are affected. I checked the history of a bunch of them, and in
most cases, there have been only a handful of maintenance changes in the
last six months. serial_core.c was the busiest one that I looked at.Signed-off-by: Jeff Dike
Acked-by: Alan Cox
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
27 Jun, 2006
2 commits
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I've always found this flag confusing. Now that devfs is no longer around, it
has been renamed, and the documentation for when this flag should be used has
been updated.Also fixes all drivers that use this flag.
Signed-off-by: Greg Kroah-Hartman
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Also fixes all drivers that set this field.
Signed-off-by: Greg Kroah-Hartman
17 Apr, 2005
1 commit
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Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.Let it rip!
