25 Jun, 2016

2 commits


01 May, 2016

3 commits

  • 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
    Signed-off-by: Greg Kroah-Hartman

    Peter Hurley
     
  • 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
    Signed-off-by: Greg Kroah-Hartman

    Peter Hurley
     
  • 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
    Signed-off-by: Greg Kroah-Hartman

    Peter Hurley
     

29 Jan, 2016

1 commit

  • 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
    Acked-by: Johan Hovold
    Signed-off-by: Greg Kroah-Hartman

    Peter Hurley
     

28 Jan, 2016

1 commit

  • The chars_in_buffer() line discipline method serves no functional
    purpose, other than as a (dubious) debugging aid for mostly bit-rotting
    drivers. Despite being documented as an optional method, every caller
    is unconditionally executed (although conditionally compiled).
    Furthermore, direct tty->ldisc access without an ldisc ref is unsafe.
    Lastly, N_TTY's chars_in_buffer() has warned of removal since 3.12.

    Signed-off-by: Peter Hurley
    Signed-off-by: Greg Kroah-Hartman

    Peter Hurley
     

14 Dec, 2015

4 commits


18 Oct, 2015

1 commit

  • 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
    Signed-off-by: Greg Kroah-Hartman

    Peter Hurley
     

07 May, 2015

1 commit

  • tty_name no longer uses the buf parameter, so remove it along with all
    the 64 byte stack buffers that used to be passed in.

    Mostly generated by the coccinelle script

    @depends on patch@
    identifier buf;
    constant C;
    expression tty;
    @@
    - char buf[C];

    allmodconfig compiles, so I'm fairly confident the stack buffers
    weren't used for other purposes as well.

    Signed-off-by: Rasmus Villemoes
    Reviewed-by: Peter Hurley
    Acked-by: Jesper Nilsson
    Acked-by: Dmitry Torokhov
    Signed-off-by: Greg Kroah-Hartman

    Rasmus Villemoes
     

11 Jul, 2014

1 commit

  • 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
    CC: Samuel Ortiz
    CC: "David S. Miller"
    Signed-off-by: Peter Hurley
    Acked-by: Jesper Nilsson
    Signed-off-by: Greg Kroah-Hartman

    Peter Hurley
     

21 Dec, 2013

1 commit

  • there is an overflow in the code :
    cyz_polling_cycle = (arg * HZ) / 1000,
    the multiplicator arg comes from user, so it may be an overflow if
    arg is a big number. And the value of cyc_polling_cycle will be
    wrong when it is used next time.

    Reported-by: Qixue Xiao
    Suggested-by: Yongjian Xu
    Suggested-by: Yu Chen
    Signed-off-by: Qixue Xiao
    Signed-off-by: Greg Kroah-Hartman

    Qixue Xiao
     

19 Mar, 2013

1 commit

  • 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
    Signed-off-by: Greg Kroah-Hartman

    Jiri Slaby
     

16 Jan, 2013

5 commits

  • Now, the tty is not needed at all places in the ISR. So we can just
    request in on demand when really needed.

    This cleans TX and RX paths a bit as the indentation level can be
    dropped by two now when we also invert the char_count if condition.

    Signed-off-by: Jiri Slaby
    Signed-off-by: Greg Kroah-Hartman

    Jiri Slaby
     
  • 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.

    This is the last one: tty_schedule_flip

    Signed-off-by: Jiri Slaby
    Signed-off-by: Greg Kroah-Hartman

    Jiri Slaby
     
  • 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_char is the next one to proceed. This one is used all
    over the code, so the patch is huge.

    Signed-off-by: Jiri Slaby
    Signed-off-by: Greg Kroah-Hartman

    Jiri Slaby
     
  • Now, we start converting tty buffer functions to actually use
    tty_port. This will allow us to get rid of the need of tty pointer in
    many call sites. Only tty_port will be needed and hence no more
    tty_port_tty_get calls in those paths.

    Now 4 string flipping ones are on turn:
    * tty_insert_flip_string_flags
    * tty_insert_flip_string_fixed_flag
    * tty_prepare_flip_string
    * tty_prepare_flip_string_flags

    Signed-off-by: Jiri Slaby
    Signed-off-by: Greg Kroah-Hartman

    Jiri Slaby
     
  • Now, we start converting tty buffer functions to actually use
    tty_port. This will allow us to get rid of the need of tty pointer in
    many call sites. Only tty_port will be needed and hence no more
    tty_port_tty_get calls in those paths.

    Here we start with tty_buffer_request_room.

    Signed-off-by: Jiri Slaby
    Signed-off-by: Greg Kroah-Hartman

    Jiri Slaby
     

22 Nov, 2012

3 commits

  • CONFIG_HOTPLUG is going away as an option so __devexit is no
    longer needed.

    Signed-off-by: Bill Pemberton
    Cc: Jiri Slaby
    Cc: Alan Cox
    Acked-by: Tobias Klauser
    Cc: Lucas Tavares
    Cc: Daniel Walker
    Cc: Bryan Huntsman
    Cc: "David S. Miller"
    Cc: Peter Korsgaard
    Cc: Tony Prisk
    Acked-by: David Brown
    Signed-off-by: Greg Kroah-Hartman

    Bill Pemberton
     
  • CONFIG_HOTPLUG is going away as an option so __devinit is no longer
    needed.

    Signed-off-by: Bill Pemberton
    Cc: Jiri Slaby
    Cc: Alan Cox
    Cc: Lucas Tavares
    Cc: "David S. Miller"
    Cc: Peter Korsgaard
    Cc: Tony Prisk
    Acked-by: Tobias Klauser
    Acked-by: Nicolas Ferre
    Signed-off-by: Greg Kroah-Hartman

    Bill Pemberton
     
  • CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
    needed.

    Signed-off-by: Bill Pemberton
    Cc: Jiri Slaby
    Signed-off-by: Greg Kroah-Hartman

    Bill Pemberton
     

16 Nov, 2012

1 commit

  • 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
    Signed-off-by: Greg Kroah-Hartman

    Jiri Slaby
     

06 Sep, 2012

1 commit

  • 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
    Signed-off-by: Greg Kroah-Hartman

    Huang Shijie
     

14 Aug, 2012

1 commit

  • Currently we have no way to assign tty->port while performing tty
    installation. There are two ways to provide the link tty_struct =>
    tty_port. Either by calling tty_port_install from tty->ops->install or
    tty_port_register_device called instead of tty_register_device when
    the device is being set up after connected.

    In this patch we modify most of the drivers to do the latter. When the
    drivers use tty_register_device and we have tty_port already, we
    switch to tty_port_register_device. So we have the tty_struct =>
    tty_port link for free for those.

    Signed-off-by: Jiri Slaby
    Acked-by: Alan Cox
    Signed-off-by: Greg Kroah-Hartman

    Jiri Slaby
     

11 Aug, 2012

1 commit

  • The termios and other changes mean the other protections needed on the driver
    tty arrays should be adequate. Turn it all back on.

    This contains pieces folded in from the fixes made to the original patches

    | From: Geert Uytterhoeven (fix m68k)
    | From: Paul Gortmaker (fix cris)
    | From: Jiri Kosina (lockdep)
    | From: Eric Dumazet (lockdep)

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

    Alan Cox
     

17 Jul, 2012

2 commits

  • 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
    Signed-off-by: Greg Kroah-Hartman

    Alan Cox
     
  • I sent GregKH this after the pre-requisites. He dropped the pre-requesites
    for good reason and unfortunately then applied this patch. Without this
    reverted you get random kernel memory corruption which will make bisecting
    anything between it and the properly applied patches a complete sod.

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

    Alan Cox
     

07 Jul, 2012

1 commit

  • The termios and other changes mean the other protections needed on the driver
    tty arrays should be adequate. Turn it all back on.

    This contains pieces folded in from the fixes made to the original patches

    | From: Geert Uytterhoeven (fix m68k)
    | From: Paul Gortmaker (fix cris)
    | From: Jiri Kosina (lockdep)
    | From: Eric Dumazet (lockdep)

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

    Alan Cox
     

13 Jun, 2012

1 commit

  • cy_pci_probe and cy_detect_isa reference cy_card[card_no] many times.
    It makes the code hard to read. Let us add a local variable holding a
    pointer to the card indexed by card_no and use that.

    Signed-off-by: Jiri Slaby
    Signed-off-by: Greg Kroah-Hartman

    Jiri Slaby
     

03 Jun, 2012

1 commit

  • This reverts the tty layer change to use per-tty locking, because it's
    not correct yet, and fixing it will require some more deep surgery.

    The main revert is d29f3ef39be4 ("tty_lock: Localise the lock"), but
    there are several smaller commits that built upon it, they also get
    reverted here. The list of reverted commits is:

    fde86d310886 - tty: add lockdep annotations
    8f6576ad476b - tty: fix ldisc lock inversion trace
    d3ca8b64b97e - pty: Fix lock inversion
    b1d679afd766 - tty: drop the pty lock during hangup
    abcefe5fc357 - tty/amiserial: Add missing argument for tty_unlock()
    fd11b42e3598 - cris: fix missing tty arg in wait_event_interruptible_tty call
    d29f3ef39be4 - tty_lock: Localise the lock

    The revert had a trivial conflict in the 68360serial.c staging driver
    that got removed in the meantime.

    Signed-off-by: Linus Torvalds

    Linus Torvalds
     

05 May, 2012

1 commit

  • In each remaining case the tty_lock is associated with a specific tty. This
    means we can now lock on a per tty basis. We do need tty_lock_pair() for
    the pty case. Uglier but still a step in the right direction.

    [fixed up calls in 3 missing drivers - gregkh]

    Signed-off-by: Alan Cox
    Acked-by: Arnd Bergmann
    Signed-off-by: Greg Kroah-Hartman

    Alan Cox
     

09 Mar, 2012

3 commits

  • Checking if tty->index is in bounds is not needed. The tty has the
    index set in the initial open. This is done in get_tty_driver. And it
    can be only in interval num).

    So remove the tests which check exactly this interval. Some are
    left untouched as they check against the current backing device count.
    (Leaving apart that the check is racy in most of the cases.)

    Signed-off-by: Jiri Slaby
    Signed-off-by: Greg Kroah-Hartman

    Jiri Slaby
     
  • All num, magic and owner are set by alloc_tty_driver. No need to
    re-set them on each allocation site.

    pti driver sets something different to what it passes to
    alloc_tty_driver. It is not a bug, since we don't use the lines
    parameter in any way. Anyway this is fixed, and now we do the right
    thing.

    Signed-off-by: Jiri Slaby
    Acked-by: Tilman Schmidt
    Signed-off-by: Greg Kroah-Hartman

    Jiri Slaby
     
  • TIOCSERGETLSR should be saved in a uint so the cast here to unsigned
    long is a bug.

    Reported-by: Jiri Slaby
    Signed-off-by: Dan Carpenter
    Acked-by: Jiri Slaby
    Signed-off-by: Greg Kroah-Hartman

    Dan Carpenter
     

23 Sep, 2011

1 commit

  • Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled],
    We run all interrupt handlers with interrupts disabled
    and we even check and yell when an interrupt handler
    returns with interrupts enabled (see commit [b738a50a:
    genirq: Warn when handler enables interrupts]).

    So now this flag is a NOOP and can be removed.

    Signed-off-by: Yong Zhang
    Acked-by: Tobias Klauser
    Signed-off-by: Greg Kroah-Hartman

    Yong Zhang
     

24 Aug, 2011

1 commit

  • It makes the code really ugly. And since it can be enabled only before
    building and only in the source files, it can be barely used by users.
    That said, I've not seen anybody to use it in the past few years.

    This crap is copied to some more drivers over the tty tree. Since I'm
    not their maintainer, I'm not sure if I should remove them too?

    Signed-off-by: Jiri Slaby
    Signed-off-by: Greg Kroah-Hartman

    Jiri Slaby
     

27 May, 2011

1 commit

  • * 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
    gfs2: Drop __TIME__ usage
    isdn/diva: Drop __TIME__ usage
    atm: Drop __TIME__ usage
    dlm: Drop __TIME__ usage
    wan/pc300: Drop __TIME__ usage
    parport: Drop __TIME__ usage
    hdlcdrv: Drop __TIME__ usage
    baycom: Drop __TIME__ usage
    pmcraid: Drop __DATE__ usage
    edac: Drop __DATE__ usage
    rio: Drop __DATE__ usage
    scsi/wd33c93: Drop __TIME__ usage
    scsi/in2000: Drop __TIME__ usage
    aacraid: Drop __TIME__ usage
    media/cx231xx: Drop __TIME__ usage
    media/radio-maxiradio: Drop __TIME__ usage
    nozomi: Drop __TIME__ usage
    cyclades: Drop __TIME__ usage

    Linus Torvalds