lkml.org 
[lkml]   [2005]   [Jun]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 1/2] Introduce tty_unregister_ldisc()
    Date
    It's a bit strange to see tty_register_ldisc call in modules' exit functions.

    Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
    ---

    Documentation/tty.txt | 2 +-
    drivers/char/tty_io.c | 35 ++++++++++++++++++++++++-----------
    include/linux/tty.h | 1 +
    3 files changed, 26 insertions(+), 12 deletions(-)

    diff -uprN linux-tty_register_ldisc_000/Documentation/tty.txt linux-tty_register_ldisc_001/Documentation/tty.txt
    --- linux-tty_register_ldisc_000/Documentation/tty.txt 2005-05-31 20:12:47.000000000 +0400
    +++ linux-tty_register_ldisc_001/Documentation/tty.txt 2005-05-31 23:19:32.000000000 +0400
    @@ -22,7 +22,7 @@ copy of the structure. You must not re-r
    discipline even with the same data or your computer again will be eaten by
    demons.

    -In order to remove a line discipline call tty_register_ldisc passing NULL.
    +In order to remove a line discipline call tty_unregister_ldisc().
    In ancient times this always worked. In modern times the function will
    return -EBUSY if the ldisc is currently in use. Since the ldisc referencing
    code manages the module counts this should not usually be a concern.
    diff -uprN linux-tty_register_ldisc_000/drivers/char/tty_io.c linux-tty_register_ldisc_001/drivers/char/tty_io.c
    --- linux-tty_register_ldisc_000/drivers/char/tty_io.c 2005-05-31 20:13:34.000000000 +0400
    +++ linux-tty_register_ldisc_001/drivers/char/tty_io.c 2005-05-31 23:17:40.000000000 +0400
    @@ -262,17 +262,10 @@ int tty_register_ldisc(int disc, struct
    return -EINVAL;

    spin_lock_irqsave(&tty_ldisc_lock, flags);
    - if (new_ldisc) {
    - tty_ldiscs[disc] = *new_ldisc;
    - tty_ldiscs[disc].num = disc;
    - tty_ldiscs[disc].flags |= LDISC_FLAG_DEFINED;
    - tty_ldiscs[disc].refcount = 0;
    - } else {
    - if(tty_ldiscs[disc].refcount)
    - ret = -EBUSY;
    - else
    - tty_ldiscs[disc].flags &= ~LDISC_FLAG_DEFINED;
    - }
    + tty_ldiscs[disc] = *new_ldisc;
    + tty_ldiscs[disc].num = disc;
    + tty_ldiscs[disc].flags |= LDISC_FLAG_DEFINED;
    + tty_ldiscs[disc].refcount = 0;
    spin_unlock_irqrestore(&tty_ldisc_lock, flags);

    return ret;
    @@ -280,6 +273,26 @@ int tty_register_ldisc(int disc, struct

    EXPORT_SYMBOL(tty_register_ldisc);

    +int tty_unregister_ldisc(int disc)
    +{
    + unsigned long flags;
    + int ret = 0;
    +
    + if (disc < N_TTY || disc >= NR_LDISCS)
    + return -EINVAL;
    +
    + spin_lock_irqsave(&tty_ldisc_lock, flags);
    + if (tty_ldiscs[disc].refcount)
    + ret = -EBUSY;
    + else
    + tty_ldiscs[disc].flags &= ~LDISC_FLAG_DEFINED;
    + spin_unlock_irqrestore(&tty_ldisc_lock, flags);
    +
    + return ret;
    +}
    +
    +EXPORT_SYMBOL(tty_unregister_ldisc);
    +
    struct tty_ldisc *tty_ldisc_get(int disc)
    {
    unsigned long flags;
    diff -uprN linux-tty_register_ldisc_000/include/linux/tty.h linux-tty_register_ldisc_001/include/linux/tty.h
    --- linux-tty_register_ldisc_000/include/linux/tty.h 2005-05-31 20:15:51.000000000 +0400
    +++ linux-tty_register_ldisc_001/include/linux/tty.h 2005-05-31 23:18:23.000000000 +0400
    @@ -345,6 +345,7 @@ extern int tty_check_change(struct tty_s
    extern void stop_tty(struct tty_struct * tty);
    extern void start_tty(struct tty_struct * tty);
    extern int tty_register_ldisc(int disc, struct tty_ldisc *new_ldisc);
    +extern int tty_unregister_ldisc(int disc);
    extern int tty_register_driver(struct tty_driver *driver);
    extern int tty_unregister_driver(struct tty_driver *driver);
    extern void tty_register_device(struct tty_driver *driver, unsigned index, struct device *dev);
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/
    \
     
     \ /
      Last update: 2005-06-15 23:50    [W:0.064 / U:0.152 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site