linux-toradex.git/include/linux/tty.h, branch v2.6.33.9

tty: Take a 256 byte padding into account when buffering below sub-page units

2010-04-01T23:01:35+00:00

commit 352fa6ad16b89f8ffd1a93b4419b1a8f2259feab upstream.

The TTY layer takes some care to ensure that only sub-page allocations
are made with interrupts disabled. It does this by setting a goal of
"TTY_BUFFER_PAGE" to allocate. Unfortunately, while TTY_BUFFER_PAGE takes the
size of tty_buffer into account, it fails to account that tty_buffer_find()
rounds the buffer size out to the next 256 byte boundary before adding on
the size of the tty_buffer.

This patch adjusts the TTY_BUFFER_PAGE calculation to take into account the
size of the tty_buffer and the padding. Once applied, tty_buffer_alloc()
should not require high-order allocations.

Signed-off-by: Mel Gorman 
Signed-off-by: Greg Kroah-Hartman

tty: Keep the default buffering to sub-page units

2010-04-01T23:01:35+00:00

commit d9661adfb8e53a7647360140af3b92284cbe52d4 upstream.

We allocate during interrupts so while our buffering is normally diced up
small anyway on some hardware at speed we can pressure the VM excessively
for page pairs. We don't really need big buffers to be linear so don't try
so hard.

In order to make this work well we will tidy up excess callers to request_room,
which cannot itself enforce this break up.

Signed-off-by: Alan Cox 
Signed-off-by: Greg Kroah-Hartman

tty.h: make tty_port_get() static inline

2010-01-16T20:15:38+00:00

I get a few dozen of these warnings when using
  gcc (GCC) 4.4.1 20090725 (Red Hat 4.4.1-2):

In file included from mmotm-2010-0113-1217/init/do_mounts.c:5:
mmotm-2010-0113-1217/include/linux/tty.h: In function 'tty_port_get':
mmotm-2010-0113-1217/include/linux/tty.h:469: warning: '______f' is static but declared in inline function 'tty_port_get' which is not static

so make the function static inline.

[akpm@linux-foundation.org: may as well convert tty_port_users() also]
Signed-off-by: Randy Dunlap 
Cc: Alan Cox 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

vt: introduce and use vt_kmsg_redirect() function

2009-12-15T16:53:28+00:00

The kernel offers with TIOCL_GETKMSGREDIRECT ioctl() the possibility to
redirect the kernel messages to a specific console.

However, since it's not possible to switch to the kernel message console
after a panic(), it would be nice if the kernel would print the panic
message on the current console.

This patch series adds a new interface to access the global kmsg_redirect
variable by a function to be able to use it in code where
CONFIG_VT_CONSOLE is not set (kernel/panic.c).

This patch:

Instead of using and exporting a global value kmsg_redirect, introduce a
function vt_kmsg_redirect() that both can set and return the console where
messages are printed.

Change all users of kmsg_redirect (the VT code itself and kernel/power.c)
to the new interface.

The main advantage is that vt_kmsg_redirect() can also be used when
CONFIG_VT_CONSOLE is not set.

Signed-off-by: Bernhard Walle 
Cc: Alan Cox 
Cc: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

tty: push the BKL down into the handlers a bit

2009-12-11T23:18:08+00:00

Start trying to untangle the remaining BKL mess

Updated to fix missing unlock_kernel noted by Dan Carpenter

Signed-off-by: Alan "I must be out of my tree" Cox 
Signed-off-by: Greg Kroah-Hartman

tty: tty_port: Add a kref object to the tty port

2009-12-11T23:18:07+00:00

Users of tty port need a way to refcount ports when hotplugging is
involved.

Signed-off-by: Alan Cox 
Signed-off-by: Greg Kroah-Hartman

tty: tty_port: Change the buffer allocator locking

2009-12-11T23:18:06+00:00

We want to be able to do this without regard for the activate/own open
method being used which causes a problem using port->mutex. Add another
mutex for now. Once everything uses port_open to do buffer allocs we can
kill it back off

Signed-off-by: Alan Cox 
Signed-off-by: Greg Kroah-Hartman

tty_port: add "tty_port_open" helper

2009-12-11T23:18:04+00:00

For the moment this just moves the USB logic over and fixes the 'what if
we open and hangup at the same time' race noticed by Oliver Neukum.

Signed-off-by: Alan Cox 
Cc: Alan Stern 
Cc: Oliver Neukum 
Signed-off-by: Greg Kroah-Hartman

tty: handle VT specific compat ioctls in vt driver

2009-09-19T20:13:35+00:00

The VT specific compat_ioctl handlers are the only ones
in common code that require the BKL. Moving them into
the vt driver lets us remove the BKL from the other handlers
and cleans up the code.

Signed-off-by: Arnd Bergmann 
Signed-off-by: Greg Kroah-Hartman

serial: move port users helper

2009-09-19T20:13:32+00:00

This little helper is now tty_port specific and useful generally so move it

Signed-off-by: Alan Cox 
Signed-off-by: Greg Kroah-Hartman