Use the standard mechanism to print a hex buffer
to eliminate empty printf warning.
A couple % smaller text and data too.
$ size drivers/tty/n_gsm.o*
text data bss dec hex filename
23543 312 6376 30231 7617 drivers/tty/n_gsm.o.new
24051 408 6496 30955 78eb drivers/tty/n_gsm.o.old
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The tty value that should be put is the one that was just gotten by
tty_port_tty_get, not the one that is the argument to the enclosing
function.
The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@exists@
local idexpression struct tty_struct *x;
expression ra,rr;
statement S1,S2;
@@
x = tty_port_tty_get(...)
... when != x = rr
when any
when != tty_kref_put(x,...)
when != if (...) { ... tty_kref_put(x,...) ...}
(
if(<+...x...+>) S1 else S2
|
if(...) { ... when != x = ra
when forall
when != tty_kref_put(x,...)
*return...;
}
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
tty_write_lock and tty_write_unlock contain imbalanced locking. But
this is intentional, so mark them appropriately by
__acquires/__releases.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
msleep* is guaranteed to return with TASK_RUNNING task state. And
since there is no other set_task_state in the paths of
uart_wait_until_sent, we need not to set_task_state to TASK_RUNNING.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
tty->index (named here as line) is set up in initialize_tty_struct.
The value is checked in get_tty_driver for the found driver as:
if (device < base || device >= base + p->num)
continue;
*index = device - base;
So index/line can never be more than driver->num. Hence remove this
test from uart_open.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
moxa_write can be called from atomic context with irqs disabled (from
ppp_async_push). Don't enable interrupts by spin_unlock_bh as this
might cause deadlocks in the ppp layer.
Instead, use irqsave/irqrestore spin_lock functions.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
tty_sem used to protect tty open count. This was removed in 33dd474a
but the lock remained in place.
So remove it completely as it protects nothing now.
Also this solves Mac's problem with inatomic operation called from
atomic context (ppp):
BUG: scheduling while atomic: firefox-bin/1992/0x10000800
Modules linked in: ...
Pid: 1992, comm: firefox-bin Not tainted 2.6.38 #1
Call Trace:
...
[] ? mutex_lock+0xe/0x21
[] ? ntty_write+0x5d/0x192 [nozomi]
[] ? __mod_timer.clone.30+0xbe/0xcc
[] ? check_preempt_curr+0x60/0x6d
[] ? __nf_ct_refresh_acct+0x75/0xbe
[] ? ppp_async_push+0xa9/0x3bd [ppp_async]
[] ? ppp_async_send+0x34/0x40 [ppp_async]
[] ? ppp_push+0x6c/0x4f9 [ppp_generic]
...
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: Mac <kmac@poczta.fm>
Tested-by: Gerald Pfeifer <gerald@pfeifer.com>
Reviewed-by: Jack Stone <jwjstone@fastmail.fm>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Before 33dd474a, these were some kind of protection against race with
HUP. They were protected with port->tty_sem at the same time.
By that commit, the counting was switched to tty_port's one, but the
locking remained the old one. So the count was not protected by
any lock anymore.
The driver should not test whether it raced with HUP or not anyways.
With the new refcounted tty model, it just should proceed as nothing
happened because all needed info is still there. In respect to this,
let's drop the useless and unprotected tests (tty_port->count is
protected by tty_port->lock).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Tested-by: Gerald Pfeifer <gerald@pfeifer.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The allocation was moved to probe function in 9842c38e91. And we can
sleep there. So allocate the 4*8192 bytes as GFP_KERNEL to mitigate
the allocation failure.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Tested-by: Gerald Pfeifer <gerald@pfeifer.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
it makes it simpler to keep track of the amount of
bytes received and simplifies how flush_to_ldisc counts
the remaining bytes. It also fixes a bug of lost bytes
on n_tty when flushing too many bytes via the USB
serial gadget driver.
Tested-by: Stefan Bigler <stefan.bigler@keymile.com>
Tested-by: Toby Gray <toby.gray@realvnc.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Traditional \E[2J sequence erases console display but scroll-back
buffer and underlying device (frame) buffer keep data that can be
accessed by scrolling console back.
This patch introduce new \E[J parameter 3 that allows to scramble
scroll-back buffer explicitly. Session locking programs (screen,
vlock) can use it to prevent attacker to browse locked console
history.
Signed-off-by: Petr Písař <ppisar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Including linux/tty.h 3 times is a little over the top - once will do.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
remove invalid location line in each file header after location
moved from driver/char to driver/tty
Signed-off-by: Jovi Zhang <bookjovi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Now, uart_update_termios is empty, so it's time to remove it. We no
longer need a live tty in .dtr_rts. So this should prune all the bugs
where tty is zeroed in port->tty during tty_port_block_til_ready.
There is one thing to note. We don't set ASYNC_NORMAL_ACTIVE now. It's
because this is done already in tty_port_block_til_ready.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In .dtr_rts we do:
uart_set_mctrl(uport, TIOCM_DTR | TIOCM_RTS)
and call uart_update_termios. It does:
uart_set_mctrl(port, TIOCM_DTR | TIOCM_RTS)
once again. As the only callsite of uart_update_termios is .dtr_rts,
remove the uart_set_mctrl from uart_update_termios to not set it twice.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We should not fiddle with speed and cflags in .dtr_rts hook. Actually
we might not have tty at that moment already.
So move the console cflag copy and speed setup into uart_startup.
Actually the speed setup is already there, but we need to call it
unconditionally (uart_startup is called from uart_open with hw_init =
0).
This means we move uart_change_speed before dtr/rts setup in .dtr_rts.
But this should not matter as the setup should be called after
uart_change_speed anyway.
Before: After:
dtr/rts setup (dtr_rts) uart_change_speed (startup)
uart_change_speed (update_termios) dtr/rts setup (dtr_rts)
dtr/rts setup (update_termios) dtr/rts setup (update_termios)
The second setup will dismiss with the next patch.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The bit is set in tty_port_block_til_ready (via moxa_open) and unset
in tty_port_close (via moxa_close). No need to pin it in the driver.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Devices extracted from device tree all seem to have pdev->id set to -1.
Up until now we mapped all devices with id -1 to the first device. This
behaviour could lead to problems when using more than one Altera UART in
a system.
This patch changes the behaviour of the driver to scan for the next free
id in case the id is -1.
Because we cannot refer back to the assigned id in altera_uart_remove,
the port instance needs to be stored in device drvdata.
Reported-by: David Smoot <davidsmoot@gmail.com>
Cc: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When tty_add_file fails we omit to clean up. Fix that by calling
tty_release appropriatelly.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Introduce deinitialize_tty_struct which should be called after
initialize_tty_struct and before successfull tty_ldisc_setup.
It calls tty_ldisc_deinit which is opposite of tty_ldisc_init. It only
puts a reference to ldisc and assigns NULL to tty->ldisc.
It will be used to shut down ldisc when tty_release cannot be called
yet.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Change it so that we call the deinit functions at one place at the end
of the function (by gotos). And while at it use some sane label names.
This is a preparation for the deinitialization of tty in the next
patch.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Change it so that we call the deinit functions at one place at the end
of the function (by gotos). And while at it use some sane label names.
This is a preparation for the deinitialization of tty in the next
patch.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Change it so that we call the deinit functions at one place at the end
of the function (by gotos). And while at it use some sane label names.
This is a preparation for the deinitialization of tty in the next
patch.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/tty/rocket.c:1393:2: warning: Value stored to 'cp' is never read
cp = &info->channel;
^ ~~~~~~~~~~~~~~
drivers/tty/rocket.c:1412:2: warning: Value stored to 'cp' is never read
cp = &info->channel;
^ ~~~~~~~~~~~~~~
drivers/tty/rocket.c:1730:2: warning: Value stored to 'cp' is never read
cp = &info->channel;
^ ~~~~~~~~~~~~~~
drivers/tty/rocket.c:1825:3: warning: Value stored to 'str' is never read
str = "8";
^ ~~~
[many 'str' warnings stripped]
drivers/tty/rocket.c:2037:3: warning: Value stored to 'board_type' is never read
board_type = "RocketModem";
^ ~~~~~~~~~~~~~
[some 'board_type' warnings stripped]
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/tty/moxa.c:1287:2: warning: Value stored to 'port' is never read
port = tty->index;
^ ~~~~~~~~~~
drivers/tty/moxa.c:1763:2: warning: Value stored to 'cflag' is never read
cflag = termio->c_cflag; /* termio->c_cflag */
^ ~~~~~~~~~~~~~~~
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/tty/vt/vt.c:892:2: warning: Value stored to 'old_screen_size' is never read
old_screen_size = vc->vc_screenbuf_size;
^ ~~~~~~~~~~~~~~~~~~~~~
drivers/tty/vt/vt.c:890:2: warning: Value stored to 'old_cols' is never read
old_cols = vc->vc_cols;
^ ~~~~~~~~~~~
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/tty/cyclades.c:1454:2: warning: Value stored to 'channel' is never read
channel = info->line - card->first_line;
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Fix it by moving it to the appropriate debug section where it is used.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
After adding support for K_OFF in KDSKBMODE, it was forgotten to
add support for returning it in KDGKBMODE.
Signed-off-by: Arthur Taylor <art@ified.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The current check is uneeded, since !retval will always returns true,
as retval returned from tty_add_file is checked earlier and tty_open
exits if it's not zero.
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Commit f23eb2b2b2 ('tty: stop using "delayed_work" in the tty layer')
ended up causing hung machines on UP with no preemption, because the
work routine to flip the buffer data to the ldisc would endlessly re-arm
itself if the destination buffer had filled up.
With the delayed work, that only caused a timer-driving polling of the
tty state every timer tick, but without the delay we just ended up with
basically a busy loop instead.
Stop the insane polling, and instead make the code that opens up the
receive room re-schedule the buffer flip work. That's what we should
have been doing anyway.
This same "poll for tty room" issue is almost certainly also the cause
of excessive kworker activity when idle reported by Dave Jones, who also
reported "flush_to_ldisc executing 2500 times a second" back in Nov 2010:
http://lkml.org/lkml/2010/11/30/592
which is that silly flushing done every timer tick. Wasting both power
and CPU for no good reason.
Reported-and-tested-by: Alexander Beregalov <a.beregalov@gmail.com>
Reported-and-tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The driver is initialized in a state with an unknown value by
serial_console_setup. And initialization fails.
This is caused by the initialization by sci_console_init.
This function does not seem to be necessary for the present sh-sci driver.
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Commit 906b17dc08 introduced a condition
where the kernel will crash unless a earlyprintk parameter is specified.
Without this parameter, sci_console_init is called during early console
setup without any port being initialized, and the kernel crashes a
little bit later when uart_set_options attemps to invoke set_termios on a
port with an ops member equal to NULL.
This patch just checks in sci_console_init that the port is properly
initialized, and aborts the early console setup if it is not.
Signed-off-by: Alexandre Courbot <gnurou@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
It absolutely needs to be able to get at pdev_archdata members
which are sparc specific.
Signed-off-by: David S. Miller <davem@davemloft.net>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
The UARTs may be located on different APB buses, thus have
different UART clock frequency. The system frequency is not
the same (but often) as the UART frequency, rather the APB bus
frequency that the APBUART is located at has the same
frequency, so this looks at the "freq" property instead.
Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
See Commit id 1636f8ac2b (sparc/of:
Move of_device fields into struct pdev_archdata), this patch
is similar to 19e4875fb2 (of/sparc:
fix build regression from of_device changes)
Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
kdb: add usage string of 'per_cpu' command
kgdb,x86_64: fix compile warning found with sparse
kdb: code cleanup to use macro instead of value
kgdboc,kgdbts: strlen() doesn't count the terminator
This is an off by one because strlen() doesn't count the null
terminator. We strcpy() these strings into an array of size
MAX_CONFIG_LEN.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Commit ddd588b5dd ("oom: suppress nodes that are not allowed from
meminfo on oom kill") moved lib/show_mem.o out of lib/lib.a, which
resulted in build warnings on all architectures that implement their own
versions of show_mem():
lib/lib.a(show_mem.o): In function `show_mem':
show_mem.c:(.text+0x1f4): multiple definition of `show_mem'
arch/sparc/mm/built-in.o:(.text+0xd70): first defined here
The fix is to remove __show_mem() and add its argument to show_mem() in
all implementations to prevent this breakage.
Architectures that implement their own show_mem() actually don't do
anything with the argument yet, but they could be made to filter nodes
that aren't allowed in the current context in the future just like the
generic implementation.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: James Bottomley <James.Bottomley@hansenpartnership.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
put_tty_driver calls tty_driver_kref_put on its argument, and then
tty_driver_kref_put calls kref_put on the address of a field of this
argument. kref_put checks for NULL, but in this case the field is likely
to have some offset and so the result of taking its address will not be
NULL. Labels are added to be able to skip over the call to put_tty_driver
when the argument will be NULL.
The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression *x;
@@
*if (x == NULL)
{ ...
* put_tty_driver(x);
...
return ...;
}
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Torben Hohn <torbenh@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Using delayed-work for tty flip buffers ends up causing us to wait for
the next tick to complete some actions. That's usually not all that
noticeable, but for certain latency-critical workloads it ends up being
totally unacceptable.
As an extreme case of this, passing a token back-and-forth over a pty
will take two ticks per iteration, so even just a thousand iterations
will take 8 seconds assuming a common 250Hz configuration.
Avoiding the whole delayed work issue brings that ping-pong test-case
down to 0.009s on my machine.
In more practical terms, this latency has been a performance problem for
things like dive computer simulators (simulating the serial interface
using the ptys) and for other environments (Alan mentions a CP/M emulator).
Reported-by: Jef Driesen <jefdriesen@telenet.be>
Acked-by: Greg KH <gregkh@suse.de>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
