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  1. 27 3月, 2013 1 次提交
  3. 23 2月, 2013 1 次提交
  5. 09 3月, 2012 1 次提交
  7. 01 11月, 2011 1 次提交
  9. 20 4月, 2011 1 次提交
  11. 02 3月, 2011 1 次提交
  13. 18 2月, 2011 2 次提交
    • J
      tty,vcs removing con_buf/conf_buf_mtx · fcdba07e
      由 Jiri Olsa 提交于 
      seems there's no longer need for using con_buf/conf_buf_mtx
as vcs_read/vcs_write buffer for user's data.

The do_con_write function, that was the other user of this,
is currently using its own kmalloc-ed buffer.

Not sure when this got changed, as I was able to find this code
in 2.6.9, but it's already gone as far as current git history
goes - 2.6.12-rc2.

AFAICS there's a behaviour change with the current change.
The lseek is not completely mutually exclusive with the
vcs_read/vcs_write - the file->f_pos might get updated
via lseek callback during the vcs_read/vcs_write processing.

I tried to find out if the prefered behaviour is to keep
this in sync within read/write/lseek functions, but I did
not find any pattern on different places.

I guess if user end up calling write/lseek from different
threads she should know what she's doing. If needed we
could use dedicated fd mutex/buffer.
Signed-off-by: NJiri Olsa <jolsa@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      fcdba07e
    • J
      tty,vcs: lseek/VC-release race fix · dc1892c4
      由 Jiri Olsa 提交于 
      there's a race between vcs's lseek handler and VC release.

The lseek handler does not hold console_lock and touches
VC's size info. If during this the VC got released, there's
an access violation.

Following program triggers the issue for me:

[SNIP]
#define _BSD_SOURCE
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/vt.h>
#include <unistd.h>
#include <errno.h>

static int run_seek(void)
{
        while(1) {
                int fd;
                fd = open("./vcs30", O_RDWR);
                while(lseek(fd, 0, 0) != -1);
                close(fd);
        }
}

static int open_ioctl_tty(void)
{
        return open("/dev/tty1", O_RDWR);
}

static int do_ioctl(int fd, int req, int i)
{
        return ioctl(fd, req, i);
}

#define INIT(i) do_ioctl(ioctl_fd, VT_ACTIVATE, i)
#define SHUT(i) do_ioctl(ioctl_fd, VT_DISALLOCATE, i)

int main(int argc, char **argv)
{
        int ioctl_fd = open_ioctl_tty();

        if (ioctl < 0) {
                perror("open tty1 failed\n");
                return -1;
        }

        if ((-1 == mknod("vcs30", S_IFCHR|0666, makedev(7, 30))) &&
            (errno != EEXIST)) {
                printf("errno %d\n", errno);
                perror("failed to create vcs30");
                return -1;
        }

        do_ioctl(ioctl_fd, VT_LOCKSWITCH, 0);

        if (!fork())
                run_seek();

        while(1) {
                INIT(30);
                SHUT(30);
        }

        return 0;
}
[SNIP]
Signed-off-by: NJiri Olsa <jolsa@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      dc1892c4
  15. 26 1月, 2011 1 次提交
    • T
      console: rename acquire/release_console_sem() to console_lock/unlock() · ac751efa
      由 Torben Hohn 提交于 
      The -rt patches change the console_semaphore to console_mutex.  As a
result, a quite large chunk of the patches changes all
acquire/release_console_sem() to acquire/release_console_mutex()

This commit makes things use more neutral function names which dont make
implications about the underlying lock.

The only real change is the return value of console_trylock which is
inverted from try_acquire_console_sem()

This patch also paves the way to switching console_sem from a semaphore to
a mutex.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: make console_trylock return 1 on success, per Geert]
Signed-off-by: NTorben Hohn <torbenh@gmx.de>
Cc: Thomas Gleixner <tglx@tglx.de>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      ac751efa
  17. 12 11月, 2010 1 次提交
  19. 05 11月, 2010 1 次提交
  21. 23 10月, 2010 2 次提交
    • N
      vcs: invoke the vt update callback when /dev/vcs* is written to · 432c9ed2
      由 Nicolas Pitre 提交于 
      A notifier chain is called whenever the vt code modifies a terminal
content, except for one case which is when the modification comes
through writes to /dev/vcs* devices.  Let's add the missing notifier
invocation at the end of vcs_write() for that case too.
Signed-off-by: NNicolas Pitre <nicolas.pitre@canonical.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      432c9ed2
    • N
      vcs: add poll/fasync support · 47725ac7
      由 Nicolas Pitre 提交于 
      The /dev/vcs* devices are used, amongst other things, by accessibility
applications such as BRLTTY to display the screen content onto refreshable
braille displays.  Currently this is performed by constantly reading from
/dev/vcsa0 whether or not the screen content has changed.  Given the
default braille refresh rate of 25 times per second, this easily qualifies
as the biggest source of wake-up events preventing laptops from entering
deeper power saving states.

To avoid this periodic polling, let's add support for select()/poll() and
SIGIO with the /dev/vcs* devices.  The implemented semantic is to report
data availability whenever the corresponding vt has seen some update after
the last read() operation.  The application still has to lseek() back
as usual in order to read() the new data.

Not to create unwanted overhead, the needed data structure is allocated
and the vt notification callback is registered only when the poll or
fasync method is invoked for the first time per file instance.
Signed-off-by: NNicolas Pitre <nicolas.pitre@canonical.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      47725ac7
  23. 11 8月, 2010 1 次提交
  25. 21 7月, 2009 1 次提交
  27. 25 3月, 2009 1 次提交
    • K
      vcs: hook sysfs devices into object lifetime instead of "binding" · 4995f8ef
      由 Kay Sievers 提交于 
      During bootup performance tracing I noticed many occurrences of
vca* device creation and removal, leading to the usual userspace
uevent processing, which are, in this case, rather pointless.

A simple test showing the kernel timing (not including all the
work userspace has to do), gives us these numbers:
  $ time for i in `seq 1000`; do echo a > /dev/tty2; done
  real    0m1.142s
  user    0m0.015s
  sys     0m0.540s

If we move the hook for the vcs* driver core devices from the
tty "binding" to the vc allocation/deallocation, which is what
the vcs* devices represent, we get the following numbers:
  $ time for i in `seq 1000`; do echo a > /dev/tty2; done
  real    0m0.152s
  user    0m0.030s
  sys     0m0.072s

Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      4995f8ef
  29. 17 10月, 2008 1 次提交
  31. 22 7月, 2008 1 次提交
  33. 21 6月, 2008 1 次提交
  35. 09 5月, 2007 2 次提交
  37. 15 2月, 2007 1 次提交
    • T
      [PATCH] remove many unneeded #includes of sched.h · cd354f1a
      由 Tim Schmielau 提交于 
      After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there.  Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.

To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.

Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm.  I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).
Signed-off-by: NTim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      cd354f1a
  39. 09 12月, 2006 1 次提交
  41. 02 12月, 2006 1 次提交
  43. 30 9月, 2006 1 次提交
  45. 04 7月, 2006 1 次提交
  47. 01 7月, 2006 1 次提交
  49. 27 6月, 2006 3 次提交
  51. 30 12月, 2005 1 次提交
    • D
      [PATCH] fix ia64 compile failure with gcc4.1 · ee025949
      由 Dave Jones 提交于 
      __get_unaligned creates a typeof the var its passed, and writes to it,
which on gcc4.1, spits out the following error:

drivers/char/vc_screen.c: In function 'vcs_write':
drivers/char/vc_screen.c:422: error: assignment of read-only variable 'val'
Signed-off-by: NDave Jones <davej@redhat.com>
[ The "right" fix would be to try to fix <asm-generic/unaligned.h>
  but that's hard to do with the tools gcc gives us. So this
  simpler patch is preferable -- Linus ]
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      ee025949
  53. 29 10月, 2005 1 次提交
  55. 21 6月, 2005 1 次提交
  57. 17 4月, 2005 1 次提交
    • L
      Linux-2.6.12-rc2 · 1da177e4
      由 Linus Torvalds 提交于 
      Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
      1da177e4