diff options
| author | Jiri Olsa <jolsa@redhat.com> | 2011-02-07 19:31:25 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-02-17 11:13:19 -0800 |
| commit | fcdba07ee390d9d9c15de8b2a17baef689284fcc (patch) | |
| tree | 607e8d1ca60006fd97c11e5c07740273d5b91895 /drivers/tty/vt/vt.c | |
| parent | dc1892c4bc6960121ca4c8023a07c815cfd689be (diff) | |
tty,vcs removing con_buf/conf_buf_mtx
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: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/tty/vt/vt.c')
| -rw-r--r-- | drivers/tty/vt/vt.c | 12 |
1 files changed, 0 insertions, 12 deletions
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index d5669ff72df4..798df6f89110 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -2068,18 +2068,6 @@ static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c) } } -/* This is a temporary buffer used to prepare a tty console write - * so that we can easily avoid touching user space while holding the - * console spinlock. It is allocated in con_init and is shared by - * this code and the vc_screen read/write tty calls. - * - * We have to allocate this statically in the kernel data section - * since console_init (and thus con_init) are called before any - * kernel memory allocation is available. - */ -char con_buf[CON_BUF_SIZE]; -DEFINE_MUTEX(con_buf_mtx); - /* is_double_width() is based on the wcwidth() implementation by * Markus Kuhn -- 2007-05-26 (Unicode 5.0) * Latest version: http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c |