If spin_lock_irqsave is called twice in a row with the same second
argument, the interrupt state at the point of the second call overwrites
the value saved by the first call. Indeed, the second call does not
need to save the interrupt state, so it is changed to a simple
spin_lock.
The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@@
expression lock1,lock2;
expression flags;
@@
*spin_lock_irqsave(lock1,flags)
... when != flags
*spin_lock_irqsave(lock2,flags)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT
This will make hardirq.h inclusion cheaper for every PREEMPT=n config
(which includes allmodconfig/allyesconfig, BTW)
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The specialix module is missing the char-major-75-* alias that would
cause it to be auto-loaded when a device of that type is opened. This
patch adds the alias.
Signed-off-by: Scott James Remnant <scott@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Create Documentation/blockdev/ sub-directory and populate it.
Populate the Documentation/serial/ sub-directory.
Move MSI-HOWTO.txt to Documentation/PCI/.
Move ioctl-number.txt to Documentation/ioctl/.
Update all relevant 00-INDEX files.
Update all relevant Kconfig files and source files.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Use the hardware break support on the specialix driver
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Go through the inlines and other oddments that are iffy. Remove various bits
of dead code and bogus debug. Turn the crtsdts compile time option into a
runtime switch.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Preparation for doing some real work on the driver. Do this first so we can
easily identify if the cleanups accidentally broke something
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Stop drivers calling their own flush method indirectly, it obfuscates code
and it will change soon anyway
- A few more lock_kernel paths temporarily needed in some driver internal
waiting code
- Remove private put_char method that does a write call for one char - we
have that anyway
- Most but not yet all of the termios copy under lock fixing (some has other
dependencies to follow)
- Note a few locking bugs in drivers found in the process
- Kill remaining [ab]users of TIOCG/SSOFTCAR in the driver, these must go to
fix the termios locking
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lock the ioctl handlers and remove bogus softcar handling.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- tqueue is used only for tty_wakeup, call it directly from the code
- tqueue_hangup for tty_hangup, it schedules its own work, use it directly
too
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
use msleep instead, because not in atomic
Cc: Roger Wolff <R.E.Wolff@BitWizard.nl>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Use timer macros to set function and data members and to modify
expiration time.
- Use DEFINE_TIMER for global timers and do not init them at run-time in
these cases.
- del_timer_sync is common in most cases -- we want to wait for timer
function if it's still running.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Paul Fulghum <paulkf@microgate.com>
Cc: Kylene Jo Hall <kjhall@us.ibm.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Acked-by: Dmitry Torokhov <dtor@mail.ru> (Input bits)
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
specialix, isr have 2 params
pt_regs are no longer the third parameter of isr, call sx_interrupt without
it.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the grungy swap all the occurrences in the right places patch that
goes with the updates. At this point we have the same functionality as
before (except that sgttyb() returns speeds not zero) and are ready to
begin turning new stuff on providing nobody reports lots of bugs
If you are a tty driver author converting an out of tree driver the only
impact should be termios->ktermios name changes for the speed/property
setting functions from your upper layers.
If you are implementing your own TCGETS function before then your driver
was broken already and its about to get a whole lot more painful for you so
please fix it 8)
Also fill in c_ispeed/ospeed on init for most devices, although the current
code will do this for you anyway but I'd like eventually to lose that extra
paranoia
[akpm@osdl.org: bluetooth fix]
[mp3@de.ibm.com: sclp fix]
[mp3@de.ibm.com: warning fix for tty3270]
[hugh@veritas.com: fix tty_ioctl powerpc build]
[jdike@addtoit.com: uml: fix ->set_termios declaration]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Correct the following bugs introduced by commit
67cc0161ecc9ebee6eba4af6cbfdba028090b1b9:
- remove one remaining and now incorrect baud_table[] usage
- "baud +=" is no longer correct
The former bug was spotted by the Coverity checker.
Rolf Eike Beer spotted a bug in the initial version of my patch.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Eliminate casts to/from void*
- Eliminate checks for conditions that never occur. These typically
fall into two classes:
1) Checking for 'dev_id == NULL', then it is never called with
NULL as an argument.
2) Checking for invalid irq number, when the only caller (the
system) guarantees the irq handler is called with the proper
'irq' number argument.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
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 <jdike@addtoit.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The driver is allocating a page but doesn't actually use it for anything.
(History from the old ->write method before Linus cleaned it up)
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
locking init cleanups:
- convert " = SPIN_LOCK_UNLOCKED" to spin_lock_init() or DEFINE_SPINLOCK()
- convert rwlocks in a similar manner
this patch was generated automatically.
Motivation:
- cleanliness
- lockdep needs control of lock initialization, which the open-coded
variants do not give
- it's also useful for -rt and for lock debugging in general
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Another bunch of checks in the char drivers .put_char() and .write()
routines, where tty can never be NULL. This patch removes these checks to
save some code. Coverity choked at those with the following bug ids:
isicom.c 767, 766
specialix.c 773, 774
synclink_cs.c 779, 781
synclink_gt.c 784, 785
synclinkmp.c 784, 785
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
tmp_buf_sem sems to be a common name for something completely unused...
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> ("usb portion")
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The API and code have been through various bits of initial review by
serial driver people but they definitely need to live somewhere for a
while so the unconverted drivers can get knocked into shape, existing
drivers that have been updated can be better tuned and bugs whacked out.
This replaces the tty flip buffers with kmalloc objects in rings. In the
normal situation for an IRQ driven serial port at typical speeds the
behaviour is pretty much the same, two buffers end up allocated and the
kernel cycles between them as before.
When there are delays or at high speed we now behave far better as the
buffer pool can grow a bit rather than lose characters. This also means
that we can operate at higher speeds reliably.
For drivers that receive characters in blocks (DMA based, USB and
especially virtualisation) the layer allows a lot of driver specific
code that works around the tty layer with private secondary queues to be
removed. The IBM folks need this sort of layer, the smart serial port
people do, the virtualisers do (because a virtualised tty typically
operates at infinite speed rather than emulating 9600 baud).
Finally many drivers had invalid and unsafe attempts to avoid buffer
overflows by directly invoking tty methods extracted out of the innards
of work queue structs. These are no longer needed and all go away. That
fixes various random hangs with serial ports on overflow.
The other change in here is to optimise the receive_room path that is
used by some callers. It turns out that only one ldisc uses receive room
except asa constant and it updates it far far less than the value is
read. We thus make it a variable not a function call.
I expect the code to contain bugs due to the size alone but I'll be
watching and squashing them and feeding out new patches as it goes.
Because the buffers now dynamically expand you should only run out of
buffering when the kernel runs out of memory for real. That means a lot of
the horrible hacks high performance drivers used to do just aren't needed any
more.
Description:
tty_insert_flip_char is an old API and continues to work as before, as does
tty_flip_buffer_push() [this is why many drivers dont need modification]. It
does now also return the number of chars inserted
There are also
tty_buffer_request_room(tty, len)
which asks for a buffer block of the length requested and returns the space
found. This improves efficiency with hardware that knows how much to
transfer.
and tty_insert_flip_string_flags(tty, str, flags, len)
to insert a string of characters and flags
For a smart interface the usual code is
len = tty_request_buffer_room(tty, amount_hardware_says);
tty_insert_flip_string(tty, buffer_from_card, len);
More description!
At the moment tty buffers are attached directly to the tty. This is causing a
lot of the problems related to tty layer locking, also problems at high speed
and also with bursty data (such as occurs in virtualised environments)
I'm working on ripping out the flip buffers and replacing them with a pool of
dynamically allocated buffers. This allows both for old style "byte I/O"
devices and also helps virtualisation and smart devices where large blocks of
data suddenely materialise and need storing.
So far so good. Lots of drivers reference tty->flip.*. Several of them also
call directly and unsafely into function pointers it provides. This will all
break. Most drivers can use tty_insert_flip_char which can be kept as an API
but others need more.
At the moment I've added the following interfaces, if people think more will
be needed now is a good time to say
int tty_buffer_request_room(tty, size)
Try and ensure at least size bytes are available, returns actual room (may be
zero). At the moment it just uses the flipbuf space but that will change.
Repeated calls without characters being added are not cumulative. (ie if you
call it with 1, 1, 1, and then 4 you'll have four characters of space. The
other functions will also try and grow buffers in future but this will be a
more efficient way when you know block sizes.
int tty_insert_flip_char(tty, ch, flag)
As before insert a character if there is room. Now returns 1 for success, 0
for failure.
int tty_insert_flip_string(tty, str, len)
Insert a block of non error characters. Returns the number inserted.
int tty_prepare_flip_string(tty, strptr, len)
Adjust the buffer to allow len characters to be added. Returns a buffer
pointer in strptr and the length available. This allows for hardware that
needs to use functions like insl or mencpy_fromio.
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes almost all inclusions of linux/version.h. The 3
#defines are unused in most of the touched files.
A few drivers use the simple KERNEL_VERSION(a,b,c) macro, which is
unfortunatly in linux/version.h.
There are also lots of #ifdef for long obsolete kernels, this was not
touched. In a few places, the linux/version.h include was move to where
the LINUX_VERSION_CODE was used.
quilt vi `find * -type f -name "*.[ch]"|xargs grep -El '(UTS_RELEASE|LINUX_VERSION_CODE|KERNEL_VERSION|linux/version.h)'|grep -Ev '(/(boot|coda|drm)/|~$)'`
search pattern:
/UTS_RELEASE\|LINUX_VERSION_CODE\|KERNEL_VERSION\|linux\/\(utsname\|version\).h
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Removed some more references to check_region().
I checked these changes into the 'checkreg' branch of
rsync://rsync.kernel.org/pub/scm/linux/kernel/git/jgarzik/misc-2.6.git
The only valid references remaining are in:
drivers/scsi/advansys.c
drivers/scsi/BusLogic.c
drivers/cdrom/sbpcd.c
sound/oss/pss.c
Remove last vestiges of ide_check_region()
drivers/char/specialix: trim trailing whitespace
drivers/char/specialix: eliminate use of check_region()
Remove outdated and unused references to check_region()
[sound oss] remove check_region() usage from cs4232, wavfront
[netdrvr eepro] trim trailing whitespace
[netdrvr eepro] remove check_region() usage
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There were still a few comments left refering to verify_area, and two
functions, verify_area_skas & verify_area_tt that just wrap corresponding
access_ok_skas & access_ok_tt functions, just like verify_area does for
access_ok - deprecate those.
There was also a few places that still used verify_area in commented-out
code, fix those up to use access_ok.
After applying this one there should not be anything left but finally
removing verify_area completely, which will happen after a kernel release
or two.
Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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!
Alan Cox