1. 11 Dec, 2009 1 commit
  2. 11 Oct, 2009 1 commit
  3. 21 Sep, 2009 1 commit
  4. 12 Jul, 2009 1 commit
  5. 11 Jun, 2009 3 commits
    • Alan Cox's avatar
      tty: rewrite the ldisc locking · c65c9bc3
      Alan Cox authored
      
      
      There are several pretty much unfixable races in the old ldisc code, especially
      with respect to pty behaviour and also to hangup. It's easier to rewrite the
      code than simply try and patch it up.
      
      This patch
      - splits the ldisc from the tty (so we will be able to refcount it more cleanly
        later)
      - introduces a mutex lock for ldisc changing on an active device
      - fixes the complete mess that hangup caused
      - implements hopefully correct setldisc/close/hangup locking
      
      There are still some problems around pty pairs that have always been there but
      at least it is now possible to understand the code and fix further problems.
      
      This fixes the following known bugs
      - hang up can leak ldisc references
      - hang up may not call open/close on ldisc in a matched way
      - pty/tty pairs can deadlock during an ldisc change
      - reading the ldisc proc files can cause every ldisc to be loaded
      
      and probably a few other of the mysterious ldisc race reports.
      
      I'm sure it also adds the odd new one.
      Signed-off-by: default avatarAlan Cox <alan@linux.intel.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c65c9bc3
    • Jiri Slaby's avatar
      epca: fix test_bit parameters · c3301a5c
      Jiri Slaby authored
      
      
      Switch from ASYNC_* to ASYNCB_*, because test_bit expects
      bit number, not mask.
      Signed-off-by: default avatarJiri Slaby <jirislaby@gmail.com>
      Signed-off-by: default avatarAlan Cox <alan@linux.intel.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c3301a5c
    • Alan Cox's avatar
      tty: Add carrier processing on close to the tty_port core · fcc8ac18
      Alan Cox authored
      
      
      Some drivers implement this internally, others miss it out. Push the
      behaviour into the core code as that way everyone will do it consistently.
      
      Update the dtr rts method to raise or lower depending upon flags. Having a
      single method in this style fits most of the implementations more cleanly than
      two funtions.
      
      We need this in place before we tackle the USB side
      Signed-off-by: default avatarAlan Cox <alan@lxorguk.ukuu.org.uk>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      fcc8ac18
  6. 06 Jan, 2009 1 commit
  7. 02 Jan, 2009 5 commits
  8. 20 Oct, 2008 1 commit
  9. 13 Oct, 2008 1 commit
  10. 22 Jul, 2008 3 commits
  11. 21 Jul, 2008 2 commits
  12. 30 Apr, 2008 4 commits
  13. 03 Feb, 2008 1 commit
  14. 17 Oct, 2007 1 commit
  15. 08 May, 2007 1 commit
  16. 05 Mar, 2007 1 commit
  17. 11 Feb, 2007 1 commit
  18. 08 Dec, 2006 1 commit
    • Alan Cox's avatar
      [PATCH] tty: switch to ktermios · 606d099c
      Alan Cox authored
      
      
      This is the grungy swap all the occurrences in the right places patch that
      goes with the updates.  At this point we have the same functionality as
      before (except that sgttyb() returns speeds not zero) and are ready to
      begin turning new stuff on providing nobody reports lots of bugs
      
      If you are a tty driver author converting an out of tree driver the only
      impact should be termios->ktermios name changes for the speed/property
      setting functions from your upper layers.
      
      If you are implementing your own TCGETS function before then your driver
      was broken already and its about to get a whole lot more painful for you so
      please fix it 8)
      
      Also fill in c_ispeed/ospeed on init for most devices, although the current
      code will do this for you anyway but I'd like eventually to lose that extra
      paranoia
      
      [akpm@osdl.org: bluetooth fix]
      [mp3@de.ibm.com: sclp fix]
      [mp3@de.ibm.com: warning fix for tty3270]
      [hugh@veritas.com: fix tty_ioctl powerpc build]
      [jdike@addtoit.com: uml: fix ->set_termios declaration]
      Signed-off-by: default avatarAlan Cox <alan@redhat.com>
      Signed-off-by: default avatarMartin Peschke <mp3@de.ibm.com>
      Acked-by: default avatarPeter Oberparleiter <oberpar@de.ibm.com>
      Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
      Signed-off-by: default avatarHugh Dickins <hugh@veritas.com>
      Signed-off-by: default avatarJeff Dike <jdike@addtoit.com>
      Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      606d099c
  19. 22 Nov, 2006 1 commit
  20. 17 Oct, 2006 1 commit
  21. 04 Oct, 2006 1 commit
  22. 02 Oct, 2006 1 commit
    • Jeff Dike's avatar
      [PATCH] const struct tty_operations · b68e31d0
      Jeff Dike authored
      
      
      As part of an SMP cleanliness pass over UML, I consted a bunch of
      structures in order to not have to document their locking.  One of these
      structures was a struct tty_operations.  In order to const it in UML
      without introducing compiler complaints, the declaration of
      tty_set_operations needs to be changed, and then all of its callers need to
      be fixed.
      
      This patch declares all struct tty_operations in the tree as const.  In all
      cases, they are static and used only as input to tty_set_operations.  As an
      extra check, I ran an i386 allyesconfig build which produced no extra
      warnings.
      
      53 drivers are affected.  I checked the history of a bunch of them, and in
      most cases, there have been only a handful of maintenance changes in the
      last six months.  serial_core.c was the busiest one that I looked at.
      Signed-off-by: default avatarJeff Dike <jdike@addtoit.com>
      Acked-by: default avatarAlan Cox <alan@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      b68e31d0
  23. 30 Jun, 2006 1 commit
  24. 28 Jun, 2006 1 commit
  25. 26 Jun, 2006 1 commit
  26. 26 Mar, 2006 1 commit
  27. 10 Jan, 2006 1 commit
    • Alan Cox's avatar
      [PATCH] TTY layer buffering revamp · 33f0f88f
      Alan Cox authored
      
      
      The API and code have been through various bits of initial review by
      serial driver people but they definitely need to live somewhere for a
      while so the unconverted drivers can get knocked into shape, existing
      drivers that have been updated can be better tuned and bugs whacked out.
      
      This replaces the tty flip buffers with kmalloc objects in rings. In the
      normal situation for an IRQ driven serial port at typical speeds the
      behaviour is pretty much the same, two buffers end up allocated and the
      kernel cycles between them as before.
      
      When there are delays or at high speed we now behave far better as the
      buffer pool can grow a bit rather than lose characters. This also means
      that we can operate at higher speeds reliably.
      
      For drivers that receive characters in blocks (DMA based, USB and
      especially virtualisation) the layer allows a lot of driver specific
      code that works around the tty layer with private secondary queues to be
      removed. The IBM folks need this sort of layer, the smart serial port
      people do, the virtualisers do (because a virtualised tty typically
      operates at infinite speed rather than emulating 9600 baud).
      
      Finally many drivers had invalid and unsafe attempts to avoid buffer
      overflows by directly invoking tty methods extracted out of the innards
      of work queue structs. These are no longer needed and all go away. That
      fixes various random hangs with serial ports on overflow.
      
      The other change in here is to optimise the receive_room path that is
      used by some callers. It turns out that only one ldisc uses receive room
      except asa constant and it updates it far far less than the value is
      read. We thus make it a variable not a function call.
      
      I expect the code to contain bugs due to the size alone but I'll be
      watching and squashing them and feeding out new patches as it goes.
      
      Because the buffers now dynamically expand you should only run out of
      buffering when the kernel runs out of memory for real.  That means a lot of
      the horrible hacks high performance drivers used to do just aren't needed any
      more.
      
      Description:
      
      tty_insert_flip_char is an old API and continues to work as before, as does
      tty_flip_buffer_push() [this is why many drivers dont need modification].  It
      does now also return the number of chars inserted
      
      There are also
      
      tty_buffer_request_room(tty, len)
      
      which asks for a buffer block of the length requested and returns the space
      found.  This improves efficiency with hardware that knows how much to
      transfer.
      
      and tty_insert_flip_string_flags(tty, str, flags, len)
      
      to insert a string of characters and flags
      
      For a smart interface the usual code is
      
          len = tty_request_buffer_room(tty, amount_hardware_says);
          tty_insert_flip_string(tty, buffer_from_card, len);
      
      More description!
      
      At the moment tty buffers are attached directly to the tty.  This is causing a
      lot of the problems related to tty layer locking, also problems at high speed
      and also with bursty data (such as occurs in virtualised environments)
      
      I'm working on ripping out the flip buffers and replacing them with a pool of
      dynamically allocated buffers.  This allows both for old style "byte I/O"
      devices and also helps virtualisation and smart devices where large blocks of
      data suddenely materialise and need storing.
      
      So far so good.  Lots of drivers reference tty->flip.*.  Several of them also
      call directly and unsafely into function pointers it provides.  This will all
      break.  Most drivers can use tty_insert_flip_char which can be kept as an API
      but others need more.
      
      At the moment I've added the following interfaces, if people think more will
      be needed now is a good time to say
      
       int tty_buffer_request_room(tty, size)
      
      Try and ensure at least size bytes are available, returns actual room (may be
      zero).  At the moment it just uses the flipbuf space but that will change.
      Repeated calls without characters being added are not cumulative.  (ie if you
      call it with 1, 1, 1, and then 4 you'll have four characters of space.  The
      other functions will also try and grow buffers in future but this will be a
      more efficient way when you know block sizes.
      
       int tty_insert_flip_char(tty, ch, flag)
      
      As before insert a character if there is room.  Now returns 1 for success, 0
      for failure.
      
       int tty_insert_flip_string(tty, str, len)
      
      Insert a block of non error characters.  Returns the number inserted.
      
       int tty_prepare_flip_string(tty, strptr, len)
      
      Adjust the buffer to allow len characters to be added.  Returns a buffer
      pointer in strptr and the length available.  This allows for hardware that
      needs to use functions like insl or mencpy_fromio.
      Signed-off-by: default avatarAlan Cox <alan@redhat.com>
      Cc: Paul Fulghum <paulkf@microgate.com>
      Signed-off-by: default avatarHirokazu Takata <takata@linux-m32r.org>
      Signed-off-by: default avatarSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: default avatarJeff Dike <jdike@addtoit.com>
      Signed-off-by: default avatarJohn Hawkes <hawkes@sgi.com>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      Signed-off-by: default avatarAdrian Bunk <bunk@stusta.de>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      33f0f88f
  28. 11 Nov, 2005 1 commit