Commit Graph

21 Commits

Author SHA1 Message Date
Alan Cox eeec32a731 nozomi: quick fix for the close/close bug
Nozomi goes wrong if you get the sequence

	open
	open
	close

	[stuff]
	close

which turns out to occur on some ppp type setups.

This is a quick patch up for the problem. It's not really fixing Nozomi
which completely fails to implement tty open/close semantics and all the
other needed stuff. Doing it right is a rather more invasive patch set and
not one that will backport.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-20 15:03:27 -08:00
Stefani Seibold 9842c38e91 kfifo: fix warn_unused_result
Fix the "ignoring return value of '...', declared with attribute
warn_unused_result" compiler warning in several users of the new kfifo
API.

It removes the __must_check attribute from kfifo_in() and
kfifo_in_locked() which must not necessary performed.

Fix the allocation bug in the nozomi driver file, by moving out the
kfifo_alloc from the interrupt handler into the probe function.

Fix the kfifo_out() and kfifo_out_locked() users to handle a unexpected
end of fifo.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-22 14:17:56 -08:00
Stefani Seibold 7acd72eb85 kfifo: rename kfifo_put... into kfifo_in... and kfifo_get... into kfifo_out...
rename kfifo_put...  into kfifo_in...  to prevent miss use of old non in
kernel-tree drivers

ditto for kfifo_get...  -> kfifo_out...

Improve the prototypes of kfifo_in and kfifo_out to make the kerneldoc
annotations more readable.

Add mini "howto porting to the new API" in kfifo.h

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-22 14:17:56 -08:00
Stefani Seibold e64c026dd0 kfifo: cleanup namespace
change name of __kfifo_* functions to kfifo_*, because the prefix __kfifo
should be reserved for internal functions only.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-22 14:17:56 -08:00
Stefani Seibold c1e13f2567 kfifo: move out spinlock
Move the pointer to the spinlock out of struct kfifo.  Most users in
tree do not actually use a spinlock, so the few exceptions now have to
call kfifo_{get,put}_locked, which takes an extra argument to a
spinlock.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-22 14:17:56 -08:00
Stefani Seibold 4546548789 kfifo: move struct kfifo in place
This is a new generic kernel FIFO implementation.

The current kernel fifo API is not very widely used, because it has to
many constrains.  Only 17 files in the current 2.6.31-rc5 used it.
FIFO's are like list's a very basic thing and a kfifo API which handles
the most use case would save a lot of development time and memory
resources.

I think this are the reasons why kfifo is not in use:

 - The API is to simple, important functions are missing
 - A fifo can be only allocated dynamically
 - There is a requirement of a spinlock whether you need it or not
 - There is no support for data records inside a fifo

So I decided to extend the kfifo in a more generic way without blowing up
the API to much.  The new API has the following benefits:

 - Generic usage: For kernel internal use and/or device driver.
 - Provide an API for the most use case.
 - Slim API: The whole API provides 25 functions.
 - Linux style habit.
 - DECLARE_KFIFO, DEFINE_KFIFO and INIT_KFIFO Macros
 - Direct copy_to_user from the fifo and copy_from_user into the fifo.
 - The kfifo itself is an in place member of the using data structure, this save an
   indirection access and does not waste the kernel allocator.
 - Lockless access: if only one reader and one writer is active on the fifo,
   which is the common use case, no additional locking is necessary.
 - Remove spinlock - give the user the freedom of choice what kind of locking to use if
   one is required.
 - Ability to handle records. Three type of records are supported:
   - Variable length records between 0-255 bytes, with a record size
     field of 1 bytes.
   - Variable length records between 0-65535 bytes, with a record size
     field of 2 bytes.
   - Fixed size records, which no record size field.
 - Preserve memory resource.
 - Performance!
 - Easy to use!

This patch:

Since most users want to have the kfifo as part of another object,
reorganize the code to allow including struct kfifo in another data
structure.  This requires changing the kfifo_alloc and kfifo_init
prototypes so that we pass an existing kfifo pointer into them.  This
patch changes the implementation and all existing users.

[akpm@linux-foundation.org: fix warning]
Signed-off-by: Stefani Seibold <stefani@seibold.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-22 14:17:55 -08:00
Alexey Dobriyan d43c36dc6b headers: remove sched.h from interrupt.h
After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-10-11 11:20:58 -07:00
Alan Cox 23198fda71 tty: fix chars_in_buffers
This function does not have an error return and returning an error is
instead interpreted as having a lot of pending bytes.

Reported by Jeff Harris who provided a list of some of the remaining
offenders.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-20 16:38:43 -07:00
Jiri Slaby 9237a81a14 tty: nozomi, fix tty refcounting bug
Don't forget to drop a tty refererence on fail paths in
receive_data().

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-16 09:19:16 -07:00
Chuck Ebbert 4d8d4d251d Remove low_latency flag setting from nozomi and mxser drivers
The kernel oopses if this flag is set.

[and neither driver should set it as they call tty_flip_buffer_push from IRQ
 paths so have always been buggy]

Signed-off-by: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-24 09:55:50 -07:00
Alan Cox 33dd474ae7 tty: kref nozomi
Update the nozomi driver to use krefs

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:40 -08:00
Alan Cox 716da631ae nozomi: Fix close on error
Nozomi assumes the close method isn't called if open errors. The tty layer
is different to other drives in this respect however. Pointed out by Denis J
Barrow.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 09:51:39 -07:00
Harvey Harrison bf9d892952 drivers/char: replace remaining __FUNCTION__ occurrences
__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>
2008-04-30 08:29:54 -07:00
Alan Cox 24cb233520 char serial: switch drivers to ioremap_nocache
Simple search/replace except for synclink.c where I noticed a real bug and
fixed it too.  It was doing NULL + offset, then checking for NULL if the remap
failed.

Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Acked-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:48 -07:00
Alan Cox 978e595f88 tty/serial: lay the foundations for the next set of reworks
- 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>
2008-04-30 08:29:45 -07:00
Al Viro 782a6de47b fix iomem misannotations in nozomi
aka if you see a force-cast, be very suspicious...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-and-tested-by: Frank Seidel <fseidel@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-30 14:20:23 -07:00
Frank Seidel 661b4e89da nozomi: fix initialization and early flow control access
Due to some flaws in the initialization and flow control
code kernel oopses could be triggered e.g. when accessing
the card too early after insertion.
See e.g. kernel.org bug #10077.
The main part of the fix is a trivial state management
making sure the card is realy ready to use before allowing
any access.

Signed-off-by: Frank Seidel <fseidel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-03-10 16:33:32 -07:00
Frank Seidel 18bbe0c26c nozomi: finish constification
Even some more constifications

Signed-off-by: Frank Seidel <fseidel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-02 15:14:48 -08:00
Jan Engelhardt 71e1b4abdc nozomi: constify driver
nozomi: constify structures and annotate vars

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Frank Seidel <fseidel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-02 15:14:48 -08:00
Frank Seidel e9ed537a3a nozomi driver update
Minor cleanups and removal of in-file changelog:

- Correction of misspellings and wrong encoded Name
- changed 'unsigned' to 'unsigned int' for better readability
- use of generic devicefile access macro
- fixed/added explanatory comment to ntty_put_char

Signed-off-by: Frank Seidel <fseidel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-02 15:14:48 -08:00
Frank Seidel 20fd1e3bea nozomi driver
This is a driver to control the cardbus wireless data card that works on
3g networks.

Greg Kroah-Hartman <gregkh@suse.de> did the initial driver cleanup.
Thanks to Arnaud Patard <apatard@mandriva.com> for help with bugfixing.
Thanks to Alan Cox for a lot of tty fixes.
Thanks to Satyam Sharma <satyam@infradead.org> for fixing buildbreakage.
Thanks to Frank Seidel <fseidel@suse.de> for a lot of bugfixes and
rewriting to make it a sane Linux driver
Thanks to Jiri Slaby <jirislaby@gmail.com> for a lot bugfixes, cleanups
and rewrites that make it much more readable.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Frank Seidel <fseidel@suse.de>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
2008-01-24 20:40:04 -08:00