Commit Graph

96 Commits

Author SHA1 Message Date
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Jiri Slaby a2a5f1a2d2 net: ircomm, cleanup TIOCGSERIAL
In ircomm_tty_get_serial_info, struct serial_struct is memset to 0 and
then some members set to 0 explicitly.

Remove the latter as it is obviously superfluous.

And remove the retinfo check against NULL. copy_to_user will take care
of that.

Part of hub6 cleanup series.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25 08:56:30 -07:00
Peter Hurley d41861ca19 tty: Replace ASYNC_INITIALIZED bit and update atomically
Replace ASYNC_INITIALIZED bit in the tty_port::flags field with
TTY_PORT_INITIALIZED bit in the tty_port::iflags field. Introduce helpers
tty_port_set_initialized() and tty_port_initialized() to abstract
atomic bit ops.

Note: the transforms for test_and_set_bit() and test_and_clear_bit()
are unnecessary as the state transitions are already mutually exclusive;
the tty lock prevents concurrent open/close/hangup.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Peter Hurley 2d68655d15 tty: Replace ASYNC_CHECK_CD and update atomically
Replace ASYNC_CHECK_CD bit in the tty_port::flags field with
TTY_PORT_CHECK_CD bit in the tty_port::iflags field. Introduce helpers
tty_port_set_check_carrier() and tty_port_check_carrier() to abstract
the atomic bit ops.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Peter Hurley 807c8d81f4 tty: Replace ASYNC_NORMAL_ACTIVE bit and update atomically
Replace ASYNC_NORMAL_ACTIVE bit in the tty_port::flags field with
TTY_PORT_ACTIVE bit in the tty_port::iflags field. Introduce helpers
tty_port_set_active() and tty_port_active() to abstract atomic bit ops.

Extract state changes from port lock sections, as this usage is
broken and confused; the state transitions are protected by the
tty lock (which mutually excludes parallel open/close/hangup),
and no user tests the active state while holding the port lock.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Peter Hurley 5604a98e2f tty: Replace ASYNC_CTS_FLOW bit and update atomically
Replace ASYNC_CTS_FLOW bit in the tty_port::flags field with
TTY_PORT_CTS_FLOW bit in the tty_port::iflags field. Add
tty_port_set_cts_flow() helper to abstract the atomic bit ops.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Peter Hurley 97ef38b821 tty: Replace TTY_THROTTLED bit tests with tty_throttled()
Abstract TTY_THROTTLED bit tests with tty_throttled().

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Peter Hurley 18900ca65a tty: Replace TTY_IO_ERROR bit tests with tty_io_error()
Abstract TTY_IO_ERROR status test treewide with tty_io_error().
NB: tty->flags uses atomic bit ops; replace non-atomic bit test
with test_bit().

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Greg Kroah-Hartman 249f3c4fe4 Merge 4.5-rc4 into tty-next
We want the fixes in here, and this resolves a merge error in tty_io.c

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-14 14:36:04 -08:00
WANG Cong 3d45296ab9 irda: fix a potential use-after-free in ircomm_param_request
self->ctrl_skb is protected by self->spinlock, we should not
access it out of the lock. Move the debugging printk inside.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-29 22:56:46 -08:00
Peter Hurley afc5ab0965 tty: Remove ASYNC_CLOSING
The tty core no longer provides nor uses ASYNC_CLOSING; remove from
tty_port_close_start() and tty_port_close_end() as well as tty drivers
which open-code these state changes. Unfortunately, even though the
bit is masked from userspace, its inclusion in a uapi header precludes
removing the macro.

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: linux-cris-kernel@axis.com
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-28 14:19:12 -08:00
Peter Hurley 9db276f8f0 tty: Use termios c_*flag macros
Expressions of the form "tty->termios.c_*flag & FLAG"
are more clearly expressed with the termios flags macros,
I_FLAG(), C_FLAG(), O_FLAG(), and L_FLAG().

Convert treewide.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-28 14:13:44 -08:00
Peter Hurley fef062cbf2 tty: Remove ASYNC_CLOSING checks in open()/hangup() methods
Since at least before 2.6.30, tty drivers that do not drop the tty lock
while closing cannot observe ASYNC_CLOSING set while holding the
tty lock; this includes the tty driver's open() and hangup() methods,
since the tty core calls these methods holding the tty lock.

For these drivers, waiting for ASYNC_CLOSING to clear while opening
is not required, since this condition cannot occur. Similarly, even
when the open() method drops and reacquires the tty lock after
blocking, ASYNC_CLOSING cannot be set (again, for drivers that
do not drop the tty lock while closing).

Now that tty port drivers no longer drop the tty lock while closing
(since 'tty: Remove tty_wait_until_sent_from_close()'), the same
conditions apply: waiting for ASYNC_CLOSING to clear while opening
is not required, nor is re-checking ASYNC_CLOSING after dropping and
reacquiring the tty lock while blocking (eg., in *_block_til_ready()).

Note: The ASYNC_CLOSING flag state is still maintained since several
bitrotting drivers use it for (dubious) other purposes.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:11:29 -07:00
Linus Torvalds bbbce516bb TTY/Serial fixes for 4.0-rc3
Here are some tty and serial driver fixes for 4.0-rc3.
 
 Along with the atime fix that you know about, here are some other serial
 driver bugfixes as well.  Most notable is a wait_until_sent bugfix that
 was traced back to being around since before 2.6.12 that Johan has fixed
 up.
 
 All have been in linux-next successfully.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are some tty and serial driver fixes for 4.0-rc3.

  Along with the atime fix that you know about, here are some other
  serial driver bugfixes as well.  Most notable is a wait_until_sent
  bugfix that was traced back to being around since before 2.6.12 that
  Johan has fixed up.

  All have been in linux-next successfully"

* tag 'tty-4.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  TTY: fix tty_wait_until_sent maximum timeout
  TTY: fix tty_wait_until_sent on 64-bit machines
  USB: serial: fix infinite wait_until_sent timeout
  TTY: bfin_jtag_comm: remove incorrect wait_until_sent operation
  net: irda: fix wait_until_sent poll timeout
  serial: uapi: Declare all userspace-visible io types
  serial: core: Fix iotype userspace breakage
  serial: sprd: Fix missing spin_unlock in sprd_handle_irq()
  console: Fix console name size mismatch
  tty: fix up atime/mtime mess, take four
  serial: 8250_dw: Fix get_mctrl behaviour
  serial:8250:8250_pci: delete unneeded quirk entries
  serial:8250:8250_pci: fix redundant entry report for WCH_CH352_2S
  Change email address for 8250_pci
  serial: 8250: Revert "tty: serial: 8250_core: read only RX if there is something in the FIFO"
  Revert "tty/serial: of_serial: add DT alias ID handling"
2015-03-08 12:25:40 -07:00
Johan Hovold 2c3fbe3cf2 net: irda: fix wait_until_sent poll timeout
In case an infinite timeout (0) is requested, the irda wait_until_sent
implementation would use a zero poll timeout rather than the default
200ms.

Note that wait_until_sent is currently never called with a 0-timeout
argument due to a bug in tty_wait_until_sent.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>	# v2.6.12
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-07 03:44:14 +01:00
Fabian Frederick a948f8ce77 irda: replace current->state by set_current_state()
Use helper functions to access current->state.
Direct assignments are prone to races and therefore buggy.

current->state = TASK_RUNNING can be replaced by __set_current_state()

Thanks to Peter Zijlstra for the exact definition of the problem.

Suggested-By: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-23 17:21:11 -05:00
Joe Perches 785c20a08b irda: Convert function pointer arrays and uses to const
Making things const is a good thing.

(x86-64 defconfig with all irda)
$ size net/irda/built-in.o*
   text	   data	    bss	    dec	    hex	filename
 109276	   1868	    244	 111388	  1b31c	net/irda/built-in.o.new
 108828	   2316	    244	 111388	  1b31c	net/irda/built-in.o.old

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-10 15:33:16 -05:00
Joe Perches a768851f94 irda: Fix build failures after IRDA_DEBUG->pr_debug
Fix the build failures that result from the use of pr_debug
without the referenced char * arrays being defined.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-12 22:01:14 -05:00
Joe Perches 955a9d202f irda: Convert IRDA_DEBUG to pr_debug
Use the normal kernel debugging mechanism which also
enables dynamic_debug at the same time.

Other miscellanea:

o Remove sysctl for irda_debug
o Remove function tracing like uses (use ftrace instead)
o Coalesce formats
o Realign arguments
o Remove unnecessary OOM messages

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-12 13:56:41 -05:00
Joe Perches 6c91023dc3 irda: Remove IRDA_<TYPE> logging macros
And use the more common mechanisms directly.

Other miscellanea:

o Coalesce formats
o Add missing newlines
o Realign arguments
o Remove unnecessary OOM message logging as
  there's a generic stack dump already on OOM.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-11 18:11:00 -05:00
Peter Hurley e359a4e38d tty: Remove tty_hung_up_p() tests from tty drivers' open()
Since at least before 2.6.30, it has not been possible to observe
a hung up file pointer in a tty driver's open() method unless/until
the driver open() releases the tty_lock() (eg., before blocking).

This is because tty_open() adds the file pointer while holding
the tty_lock() _and_ doesn't release the lock until after calling
the tty driver's open() method. [ Before tty_lock(), this was
lock_kernel(). ]

Since __tty_hangup() first waits on the tty_lock() before
enumerating and hanging up the open file pointers, either
__tty_hangup() will wait for the tty_lock() or tty_open() will
not yet have added the file pointer. For example,

CPU 0                          |  CPU 1
                               |
tty_open                       |  __tty_hangup
  ..                           |    ..
  tty_lock                     |    ..
  tty_reopen                   |    tty_lock  / blocks
  ..                           |
  tty_add_file(tty, filp)      |
  ..                           |
  tty->ops->open(tty, filp)    |
    tty_port_open              |
      tty_port_block_til_ready |
        ..                     |
        while (1)              |
          ..                   |
          tty_unlock           |    / unblocks
          schedule             |    for each filp on tty->tty_files
                               |      f_ops = tty_hung_up_fops;
                               |    ..
                               |    tty_unlock
          tty_lock             |
  ..                           |
  tty_unlock                   |

Note that since tty_port_block_til_ready() and similar drop
the tty_lock while blocking, when woken, the file pointer
must then be tested for having been hung up.

Also, fix bit-rotted drivers that used extra_count to track the
port->count bump.

CC: Mikael Starvik <starvik@axis.com>
CC: Samuel Ortiz <samuel@sortiz.org>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-10 16:06:49 -07:00
Jeff Kirsher d37705092f net/irda: Fix FSF address in file headers
Several files refer to an old address for the Free Software Foundation
in the file header comment.  Resolve by replacing the address with
the URL <http://www.gnu.org/licenses/> so that we do not have to keep
updating the header comments anytime the address changes.

CC: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06 12:37:57 -05:00
Linus Torvalds 73287a43cc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights (1721 non-merge commits, this has to be a record of some
  sort):

   1) Add 'random' mode to team driver, from Jiri Pirko and Eric
      Dumazet.

   2) Make it so that any driver that supports configuration of multiple
      MAC addresses can provide the forwarding database add and del
      calls by providing a default implementation and hooking that up if
      the driver doesn't have an explicit set of handlers.  From Vlad
      Yasevich.

   3) Support GSO segmentation over tunnels and other encapsulating
      devices such as VXLAN, from Pravin B Shelar.

   4) Support L2 GRE tunnels in the flow dissector, from Michael Dalton.

   5) Implement Tail Loss Probe (TLP) detection in TCP, from Nandita
      Dukkipati.

   6) In the PHY layer, allow supporting wake-on-lan in situations where
      the PHY registers have to be written for it to be configured.

      Use it to support wake-on-lan in mv643xx_eth.

      From Michael Stapelberg.

   7) Significantly improve firewire IPV6 support, from YOSHIFUJI
      Hideaki.

   8) Allow multiple packets to be sent in a single transmission using
      network coding in batman-adv, from Martin Hundebøll.

   9) Add support for T5 cxgb4 chips, from Santosh Rastapur.

  10) Generalize the VXLAN forwarding tables so that there is more
      flexibility in configurating various aspects of the endpoints.
      From David Stevens.

  11) Support RSS and TSO in hardware over GRE tunnels in bxn2x driver,
      from Dmitry Kravkov.

  12) Zero copy support in nfnelink_queue, from Eric Dumazet and Pablo
      Neira Ayuso.

  13) Start adding networking selftests.

  14) In situations of overload on the same AF_PACKET fanout socket, or
      per-cpu packet receive queue, minimize drop by distributing the
      load to other cpus/fanouts.  From Willem de Bruijn and Eric
      Dumazet.

  15) Add support for new payload offset BPF instruction, from Daniel
      Borkmann.

  16) Convert several drivers over to mdoule_platform_driver(), from
      Sachin Kamat.

  17) Provide a minimal BPF JIT image disassembler userspace tool, from
      Daniel Borkmann.

  18) Rewrite F-RTO implementation in TCP to match the final
      specification of it in RFC4138 and RFC5682.  From Yuchung Cheng.

  19) Provide netlink socket diag of netlink sockets ("Yo dawg, I hear
      you like netlink, so I implemented netlink dumping of netlink
      sockets.") From Andrey Vagin.

  20) Remove ugly passing of rtnetlink attributes into rtnl_doit
      functions, from Thomas Graf.

  21) Allow userspace to be able to see if a configuration change occurs
      in the middle of an address or device list dump, from Nicolas
      Dichtel.

  22) Support RFC3168 ECN protection for ipv6 fragments, from Hannes
      Frederic Sowa.

  23) Increase accuracy of packet length used by packet scheduler, from
      Jason Wang.

  24) Beginning set of changes to make ipv4/ipv6 fragment handling more
      scalable and less susceptible to overload and locking contention,
      from Jesper Dangaard Brouer.

  25) Get rid of using non-type-safe NLMSG_* macros and use nlmsg_*()
      instead.  From Hong Zhiguo.

  26) Optimize route usage in IPVS by avoiding reference counting where
      possible, from Julian Anastasov.

  27) Convert IPVS schedulers to RCU, also from Julian Anastasov.

  28) Support cpu fanouts in xt_NFQUEUE netfilter target, from Holger
      Eitzenberger.

  29) Network namespace support for nf_log, ebt_log, xt_LOG, ipt_ULOG,
      nfnetlink_log, and nfnetlink_queue.  From Gao feng.

  30) Implement RFC3168 ECN protection, from Hannes Frederic Sowa.

  31) Support several new r8169 chips, from Hayes Wang.

  32) Support tokenized interface identifiers in ipv6, from Daniel
      Borkmann.

  33) Use usbnet_link_change() helper in USB net driver, from Ming Lei.

  34) Add 802.1ad vlan offload support, from Patrick McHardy.

  35) Support mmap() based netlink communication, also from Patrick
      McHardy.

  36) Support HW timestamping in mlx4 driver, from Amir Vadai.

  37) Rationalize AF_PACKET packet timestamping when transmitting, from
      Willem de Bruijn and Daniel Borkmann.

  38) Bring parity to what's provided by /proc/net/packet socket dumping
      and the info provided by netlink socket dumping of AF_PACKET
      sockets.  From Nicolas Dichtel.

  39) Fix peeking beyond zero sized SKBs in AF_UNIX, from Benjamin
      Poirier"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1722 commits)
  filter: fix va_list build error
  af_unix: fix a fatal race with bit fields
  bnx2x: Prevent memory leak when cnic is absent
  bnx2x: correct reading of speed capabilities
  net: sctp: attribute printl with __printf for gcc fmt checks
  netlink: kconfig: move mmap i/o into netlink kconfig
  netpoll: convert mutex into a semaphore
  netlink: Fix skb ref counting.
  net_sched: act_ipt forward compat with xtables
  mlx4_en: fix a build error on 32bit arches
  Revert "bnx2x: allow nvram test to run when device is down"
  bridge: avoid OOPS if root port not found
  drivers: net: cpsw: fix kernel warn on cpsw irq enable
  sh_eth: use random MAC address if no valid one supplied
  3c509.c: call SET_NETDEV_DEV for all device types (ISA/ISAPnP/EISA)
  tg3: fix to append hardware time stamping flags
  unix/stream: fix peeking with an offset larger than data in queue
  unix/dgram: fix peeking with an offset larger than data in queue
  unix/dgram: peek beyond 0-sized skbs
  openvswitch: Remove unneeded ovs_netdev_get_ifindex()
  ...
2013-05-01 14:08:52 -07:00
Johan Hovold e1c969f781 TTY: ircomm: fix DTR being raised on hang up
Make sure to check ASYNC_INITIALISED before raising DTR when waking up
from blocked open in ircomm_tty_block_til_ready.

Currently DTR could get raised at hang up as a blocked process would
raise DTR unconditionally before checking for hang up and returning.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-12 14:08:18 -07:00
Mathias Krause c17277f7d7 TTY: ircomm, use GFP_KERNEL in ircomm_open()
Hi Greg,

I'm unsure if you or Dave should take that one as it's for one a TTY
patch but also living under net/. So I'm uncertain and let you decide!

Thanks,
Mathias

-- >8 --
Subject: [PATCH] TTY: ircomm, use GFP_KERNEL in ircomm_open()

We're clearly running in non-atomic context as our only call site is
able to call wait_event_interruptible(). So we're safe to use GFP_KERNEL
here instead of GFP_ATOMIC.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-08 12:09:18 -04:00
Greg Kroah-Hartman 23a376f98c Merge 3.9-rc3 into tty-next 2013-03-21 16:07:34 -07:00
Jiri Slaby aa27a094e2 TTY: add tty_port_tty_hangup helper
It allows for cleaning up on a considerable amount of places. They did
port_get, hangup, kref_put. Now the only thing needed is to call
tty_port_tty_hangup which does exactly that. And they can also decide
whether to consider CLOCAL or completely ignore that.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-18 16:24:29 -07:00
Peter Hurley f74861ca87 net/irda: Raise dtr in non-blocking open
DTR/RTS need to be raised, regardless of the open() mode, but not
if the port has already shutdown.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-06 02:47:05 -05:00
Peter Hurley 0b176ce3a7 net/irda: Use barrier to set task state
Without a memory and compiler barrier, the task state change
can migrate relative to the condition testing in a blocking loop.
However, the task state change must be visible across all cpus
prior to testing those conditions. Failing to do this can result
in the familiar 'lost wakeup' and this task will hang until killed.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-06 02:47:04 -05:00
Peter Hurley 2f7c069b96 net/irda: Hold port lock while bumping blocked_open
Although tty_lock() already protects concurrent update to
blocked_open, that fails to meet the separation-of-concerns between
tty_port and tty.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-06 02:47:04 -05:00
Peter Hurley a4ed2e737c net/irda: Fix port open counts
Saving the port count bump is unsafe. If the tty is hung up while
this open was blocking, the port count is zeroed.

Explicitly check if the tty was hung up while blocking, and correct
the port count if not.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-06 02:47:04 -05:00
Joe Millenbach 4f73bc4dd3 tty: Added a CONFIG_TTY option to allow removal of TTY
The option allows you to remove TTY and compile without errors. This
saves space on systems that won't support TTY interfaces anyway.
bloat-o-meter output is below.

The bulk of this patch consists of Kconfig changes adding "depends on
TTY" to various serial devices and similar drivers that require the TTY
layer.  Ideally, these dependencies would occur on a common intermediate
symbol such as SERIO, but most drivers "select SERIO" rather than
"depends on SERIO", and "select" does not respect dependencies.

bloat-o-meter output comparing our previous minimal to new minimal by
removing TTY.  The list is filtered to not show removed entries with awk
'$3 != "-"' as the list was very long.

add/remove: 0/226 grow/shrink: 2/14 up/down: 6/-35356 (-35350)
function                                     old     new   delta
chr_dev_init                                 166     170      +4
allow_signal                                  80      82      +2
static.__warned                              143     142      -1
disallow_signal                               63      62      -1
__set_special_pids                            95      94      -1
unregister_console                           126     121      -5
start_kernel                                 546     541      -5
register_console                             593     588      -5
copy_from_user                                45      40      -5
sys_setsid                                   128     120      -8
sys_vhangup                                   32      19     -13
do_exit                                     1543    1526     -17
bitmap_zero                                   60      40     -20
arch_local_irq_save                          137     117     -20
release_task                                 674     652     -22
static.spin_unlock_irqrestore                308     260     -48

Signed-off-by: Joe Millenbach <jmillenbach@gmail.com>
Reviewed-by: Jamey Sharp <jamey@minilop.net>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-18 16:15:27 -08:00
Jiri Slaby 2e124b4a39 TTY: switch tty_flip_buffer_push
Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

Now, the one where most of tty_port_tty_get gets removed:
tty_flip_buffer_push.

IOW we also closed all the races in drivers not using tty_port_tty_get
at all yet.

Also we move tty_flip_buffer_push declaration from include/linux/tty.h
to include/linux/tty_flip.h to all others while we are changing it
anyway.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 22:30:15 -08:00
Jiri Slaby d6c53c0e9b TTY: move low_latency to tty_port
One point is to have less places where we actually need tty pointer.
The other is that low_latency is bound to buffer processing and
buffers are now in tty_port. So it makes sense to move low_latency to
tty_port too.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 22:23:16 -08:00
Jiri Slaby 05c7cd3990 TTY: switch tty_insert_flip_string
Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

tty_insert_flip_string this time.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 22:22:35 -08:00
Jiri Slaby 191c5f1027 TTY: call tty_port_destroy in the rest of drivers
After commit "TTY: move tty buffers to tty_port", the tty buffers are
not freed in some drivers. This is because tty_port_destructor is not
called whenever a tty_port is freed. This was an assumption I counted
with but was unfortunately untrue. So fix the drivers to fulfil this
assumption.

To be sure, the TTY buffers (and later some stuff) are gone along with
the tty_port, we have to call tty_port_destroy at tear-down places.
This is mostly where the structure containing a tty_port is freed.
This patch does exactly that -- put tty_port_destroy at those places.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 17:20:58 -08:00
Sasha Levin 6f5601251d net, TTY: initialize tty->driver_data before usage
Commit 9c650ffc ("TTY: ircomm_tty, add tty install") split _open() to
_install() and _open(). It also moved the initialization of driver_data
out of open(), but never added it to install() - causing a NULL ptr
deref whenever the driver was used.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-05 09:26:01 -07:00
Huang Shijie f21ec3d2d4 serial: add a new helper function
In most of the time, the driver needs to check if the cts flow control
is enabled. But now, the driver checks the ASYNC_CTS_FLOW flag manually,
which is not a grace way. So add a new wraper function to make the code
tidy and clean.

Signed-off-by: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-05 13:28:35 -07:00
Jiri Slaby 9c650ffc27 TTY: ircomm_tty, add tty install
This has two outcomes:
* we give the TTY layer a tty_port
* we do not find the info structure every time open is called on that
  tty

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-13 16:53:14 -07:00
Alan Cox adc8d746ca tty: move the termios object into the tty
This will let us sort out a whole pile of tty related races. The
alternative would be to keep points and refcount the termios objects.
However
1. They are tiny anyway
2. Many devices don't use the stored copies
3. We can remove a pty special case

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16 13:00:41 -07:00
Jiri Slaby c0e7865003 TTY: ircomm, use tty_port_close_start helper
Again, the code is identical, so leverage the helper code.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-12 15:50:24 -07:00
Jiri Slaby a1e844036a TTY: ircomm, use tty_port_close_end helper
Again, the code is identical, so leverage the helper code.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-12 15:50:24 -07:00
Jiri Slaby 0ba9ff846b TTY: ircomm, define carrier routines
These will be used by the tty_port wait_til_ready later. (Now they are
used by our code.)

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-12 15:50:24 -07:00
Jiri Slaby 38c58032f0 TTY: ircomm, define local tty_port
In some functions we use tty_port heavily. So let us have a local
pointer to that variable instead of having self->port all over the
code.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-12 15:50:24 -07:00
Jiri Slaby 62f228acb8 TTY: ircomm, use tty from tty_port
This also includes a switch to tty refcounting. It makes sure, the
code no longer can access a freed TTY struct.

Sometimes the only thing needed is to pass tty down to the callies.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-12 15:50:24 -07:00
Jiri Slaby e673927d8a TTY: ircomm, revamp locking
Use self->spinlock only for ctrl_skb and tx_skb. TTY stuff is now
protected by tty_port->lock. This is needed for further cleanup (and
conversion to tty_port helpers).

This also closes the race in the end of close.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-12 15:50:23 -07:00
Jiri Slaby 849d5a997f TTY: ircomm, use flags from tty_port
Switch to tty_port->flags. And while at it, remove redefined flags for
them.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-12 15:50:23 -07:00
Jiri Slaby 580d27b449 TTY: ircomm, use open counts from tty_port
Switch to tty_port->count and blocked_open.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-12 15:50:23 -07:00
Jiri Slaby 2a0213cb1e TTY: ircomm, use close times from tty_port
Switch to tty_port->close_delay and closing_wait.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-12 15:50:23 -07:00
Jiri Slaby a3cc9fcff8 TTY: ircomm, add tty_port
And use close/open_wait from there.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-12 15:50:23 -07:00