There are several pretty much unfixable races in the old ldisc code, especially
with respect to pty behaviour and also to hangup. It's easier to rewrite the
code than simply try and patch it up.
This patch
- splits the ldisc from the tty (so we will be able to refcount it more cleanly
later)
- introduces a mutex lock for ldisc changing on an active device
- fixes the complete mess that hangup caused
- implements hopefully correct setldisc/close/hangup locking
There are still some problems around pty pairs that have always been there but
at least it is now possible to understand the code and fix further problems.
This fixes the following known bugs
- hang up can leak ldisc references
- hang up may not call open/close on ldisc in a matched way
- pty/tty pairs can deadlock during an ldisc change
- reading the ldisc proc files can cause every ldisc to be loaded
and probably a few other of the mysterious ldisc race reports.
I'm sure it also adds the odd new one.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Set up ports right after FW load so that we won't allocate maximal
(64) ports when we use few.
Also remove reading of nports in irq context, since we know it from
initialisation now.
This also fixes a tty ports unregistration on some fail paths and for
Ze which registered 64 and unregistered real port count.
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>
Remove ugly all-over-the-code casts of ctl_addr to 9060 space.
Add an union to the cyclades_card structure, which contains
a pointer to both 9050 and 9060 spaces.
The 9050 space layout is unknown, so let it still as a void
__iomem pointer.
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>
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 <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move the line disciplines towards a conventional ->ops arrangement. For
the moment the actual 'tty_ldisc' struct in the tty is kept as part of
the tty struct but this can then be changed if it turns out that when it
all settles down we want to refcount ldiscs separately to the tty.
Pull the ldisc code out of /proc and put it with our ldisc code.
Signed-off-by: Alan Cox <alan@redhat.com>
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>
Nested min() macros.
drivers/char/cyclades.c:2750:7: warning: symbol '_x' shadows an earlier one
drivers/char/cyclades.c:2750:7: originally declared here
drivers/char/cyclades.c:2750:7: warning: symbol '_x' shadows an earlier one
drivers/char/cyclades.c:2750:7: originally declared here
drivers/char/cyclades.c:2750:7: warning: symbol '_y' shadows an earlier one
drivers/char/cyclades.c:2750:7: originally declared here
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>
ztxdone is jumped to even if tty is NULL and tty_wakeup placed after
this label doesn't expect NULLed parameter, so this will cause an oops
in some situations (why they scheduled a wakeup there before remove
bottom half processing patch?).
wakeup only in the case when we have non-null tty struct.
Spotted by Adrian Bunk.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Convert files to UTF-8.
* Also correct some people's names
(one example is Eißfeldt, which was found in a source file.
Given that the author used an ß at all in a source file
indicates that the real name has in fact a 'ß' and not an 'ss',
which is commonly used as a substitute for 'ß' when limited to
7bit.)
* Correct town names (Goettingen -> Göttingen)
* Update Eberhard Mönkeberg's address (http://lkml.org/lkml/2007/1/8/313)
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Lock whole processing in isr, avoid error-prone locking/unlocking in rx/tx
esp. On fail paths (there was a bug in the past yet).
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>
Due to large indent the code was wrapped and unreadable. Create 3 function
instead of one and reorder the code, so it is readable now.
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>
Mark variables in drivers/* with uninitialized_var() if such a warning
appears, and analysis proves that the var is initialized properly on all
paths it is used.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
- 0 is not NULL
- use unlikely to hit the icache in isr more likely
- remove or comment empty if/else paths
[akpm@linux-foundation.org: build fix]
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>
