Commit Graph

10 Commits

Author SHA1 Message Date
Oliver Hartkopp 174c95d252 slcan: ldisc generated skbs are received in softirq context
As this discussion pointed out

http://marc.info/?l=linux-netdev&m=131257225602375

netdevices that are based on serial line disciplines should use netif_rx_ni()
when pushing received socketbuffers into the netdev rx queue.

Following commit 614851601c ("slip: fix NOHZ
local_softirq_pending 08 warning") this patch updates the slcan driver
accordingly.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
CC: Matvejchikov Ilya <matvejchikov@gmail.com>
CC: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-11 05:52:57 -07:00
Matvejchikov Ilya 7ad711b49e slcan: remove unused 'leased', 'line' and 'pid' fields from the 'slcan' structure
Signed-off-by: Matvejchikov Ilya <matvejchikov@gmail.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 16:55:42 -07:00
Andy Shevchenko 81fc70d865 net: can: remove custom hex_to_bin()
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-18 11:31:43 -07:00
Oliver Hartkopp 2af4ba8591 slcan: remove obsolete code in slcan initialisation
This patch removes obsolete code in the initialisation/creation of
slcan devices.

It follows the suggested cleanups from Ilya Matvejchikov in
drivers/net/slip.c that where recently applied to net-next-2.6:

- slip: remove dead code within the slip initialization
- slip: remove redundant check slip_devs for NULL

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-15 08:08:26 -07:00
Linus Torvalds 55db4c64ed Revert "tty: make receive_buf() return the amout of bytes received"
This reverts commit b1c43f82c5.

It was broken in so many ways, and results in random odd pty issues.

It re-introduced the buggy schedule_work() in flush_to_ldisc() that can
cause endless work-loops (see commit a5660b41af6a: "tty: fix endless
work loop when the buffer fills up").

It also used an "unsigned int" return value fo the ->receive_buf()
function, but then made multiple functions return a negative error code,
and didn't actually check for the error in the caller.

And it didn't actually work at all.  BenH bisected down odd tty behavior
to it:
  "It looks like the patch is causing some major malfunctions of the X
   server for me, possibly related to PTYs.  For example, cat'ing a
   large file in a gnome terminal hangs the kernel for -minutes- in a
   loop of what looks like flush_to_ldisc/workqueue code, (some ftrace
   data in the quoted bits further down).

   ...

   Some more data: It -looks- like what happens is that the
   flush_to_ldisc work queue entry constantly re-queues itself (because
   the PTY is full ?) and the workqueue thread will basically loop
   forver calling it without ever scheduling, thus starving the consumer
   process that could have emptied the PTY."

which is pretty much exactly the problem we fixed in a5660b41af.

Milton Miller pointed out the 'unsigned int' issue.

Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reported-by: Milton Miller <miltonm@bga.com>
Cc: Stefan Bigler <stefan.bigler@keymile.com>
Cc: Toby Gray <toby.gray@realvnc.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-04 06:33:24 +09:00
Linus Torvalds 99dff58562 Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6
* 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (48 commits)
  serial: 8250_pci: add support for Cronyx Omega PCI multiserial board.
  tty/serial: Fix break handling for PORT_TEGRA
  tty/serial: Add explicit PORT_TEGRA type
  n_tracerouter and n_tracesink ldisc additions.
  Intel PTI implementaiton of MIPI 1149.7.
  Kernel documentation for the PTI feature.
  export kernel call get_task_comm().
  tty: Remove to support serial for S5P6442
  pch_phub: Support new device ML7223
  8250_pci: Add support for the Digi/IBM PCIe 2-port Adapter
  ASoC: Update cx20442 for TTY API change
  pch_uart: Support new device ML7223 IOH
  parport: Use request_muxed_region for IT87 probe and lock
  tty/serial: add support for Xilinx PS UART
  n_gsm: Use print_hex_dump_bytes
  drivers/tty/moxa.c: Put correct tty value
  TTY: tty_io, annotate locking functions
  TTY: serial_core, remove superfluous set_task_state
  TTY: serial_core, remove invalid test
  Char: moxa, fix locking in moxa_write
  ...

Fix up trivial conflicts in drivers/bluetooth/hci_ldisc.c and
drivers/tty/serial/Makefile.

I did the hci_ldisc thing as an evil merge, cleaning things up.
2011-05-23 12:23:20 -07:00
Oliver Hartkopp 0d4420a90b slcan: fix ldisc->open retval
TTY layer expects 0 if the ldisc->open operation succeeded.

Reported-by: Matvejchikov Ilya <matvejchikov@gmail.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-10 15:04:07 -07:00
Felipe Balbi b1c43f82c5 tty: make receive_buf() return the amout of bytes received
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>
2011-04-22 17:31:53 -07:00
David S. Miller 84b3cdc38c can: slcan: Add missing linux/sched.h include.
drivers/net/can/slcan.c: In function 'slcan_open':
drivers/net/can/slcan.c:568: error: dereferencing pointer to incomplete type

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-08 18:41:03 -08:00
Oliver Hartkopp a1044e36e4 can: add slcan driver for serial/USB-serial CAN adapters
This patch adds support for serial/USB-serial CAN adapters implementing the
LAWICEL ASCII protocol for CAN frame transport over serial lines.

The driver implements the SLCAN line discipline and is heavily based on the
slip.c driver. Therefore the code style remains similar to slip.c to be able
to apply changes of the SLIP driver to the SLCAN driver easily.

For more details see the slcan Kconfig entry.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-08 09:03:32 -08:00