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-rw-r--r--drivers/char/cyclades.c3
-rw-r--r--drivers/char/epca.c4
-rw-r--r--drivers/char/ip2/i2lib.c4
-rw-r--r--drivers/char/ip2/ip2main.c7
-rw-r--r--drivers/char/n_hdlc.c6
-rw-r--r--drivers/char/n_r3964.c2
-rw-r--r--drivers/char/n_tty.c2
-rw-r--r--drivers/char/pcmcia/synclink_cs.c4
-rw-r--r--drivers/char/pty.c10
-rw-r--r--drivers/char/selection.c3
-rw-r--r--drivers/char/synclink.c4
-rw-r--r--drivers/char/synclink_gt.c4
-rw-r--r--drivers/char/synclinkmp.c4
-rw-r--r--drivers/char/tty_io.c336
-rw-r--r--drivers/char/tty_ioctl.c16
15 files changed, 251 insertions, 158 deletions
diff --git a/drivers/char/cyclades.c b/drivers/char/cyclades.c
index 6bff9d87dc57..a957dbcc5a46 100644
--- a/drivers/char/cyclades.c
+++ b/drivers/char/cyclades.c
@@ -5246,7 +5246,8 @@ cyclades_get_proc_info(char *buf, char **start, off_t offset, int length,
HZ, info->idle_stats.recv_bytes,
(cur_jifs - info->idle_stats.recv_idle)/
HZ, info->idle_stats.overruns,
- (long)info->tty->ldisc.num);
+ /* FIXME: double check locking */
+ (long)info->tty->ldisc.ops->num);
else
size = sprintf(buf + len, "%3d %8lu %10lu %8lu "
"%10lu %8lu %9lu %6ld\n",
diff --git a/drivers/char/epca.c b/drivers/char/epca.c
index 60a4df7dac12..aa8e19f44b45 100644
--- a/drivers/char/epca.c
+++ b/drivers/char/epca.c
@@ -2262,8 +2262,8 @@ static int pc_ioctl(struct tty_struct *tty, struct file *file,
tty_wait_until_sent(tty, 0);
} else {
/* ldisc lock already held in ioctl */
- if (tty->ldisc.flush_buffer)
- tty->ldisc.flush_buffer(tty);
+ if (tty->ldisc.ops->flush_buffer)
+ tty->ldisc.ops->flush_buffer(tty);
}
unlock_kernel();
/* Fall Thru */
diff --git a/drivers/char/ip2/i2lib.c b/drivers/char/ip2/i2lib.c
index 938879cc7bcc..0061e18aff60 100644
--- a/drivers/char/ip2/i2lib.c
+++ b/drivers/char/ip2/i2lib.c
@@ -868,11 +868,11 @@ i2Input(i2ChanStrPtr pCh)
amountToMove = count;
}
// Move the first block
- pCh->pTTY->ldisc.receive_buf( pCh->pTTY,
+ pCh->pTTY->ldisc.ops->receive_buf( pCh->pTTY,
&(pCh->Ibuf[stripIndex]), NULL, amountToMove );
// If we needed to wrap, do the second data move
if (count > amountToMove) {
- pCh->pTTY->ldisc.receive_buf( pCh->pTTY,
+ pCh->pTTY->ldisc.ops->receive_buf( pCh->pTTY,
pCh->Ibuf, NULL, count - amountToMove );
}
// Bump and wrap the stripIndex all at once by the amount of data read. This
diff --git a/drivers/char/ip2/ip2main.c b/drivers/char/ip2/ip2main.c
index 9a2394cda943..5dc74404058f 100644
--- a/drivers/char/ip2/ip2main.c
+++ b/drivers/char/ip2/ip2main.c
@@ -1289,11 +1289,12 @@ static void do_input(struct work_struct *work)
// code duplicated from n_tty (ldisc)
static inline void isig(int sig, struct tty_struct *tty, int flush)
{
+ /* FIXME: This is completely bogus */
if (tty->pgrp)
kill_pgrp(tty->pgrp, sig, 1);
if (flush || !L_NOFLSH(tty)) {
- if ( tty->ldisc.flush_buffer )
- tty->ldisc.flush_buffer(tty);
+ if ( tty->ldisc.ops->flush_buffer )
+ tty->ldisc.ops->flush_buffer(tty);
i2InputFlush( tty->driver_data );
}
}
@@ -1342,7 +1343,7 @@ static void do_status(struct work_struct *work)
}
tmp = pCh->pTTY->real_raw;
pCh->pTTY->real_raw = 0;
- pCh->pTTY->ldisc.receive_buf( pCh->pTTY, &brkc, &brkf, 1 );
+ pCh->pTTY->ldisc->ops.receive_buf( pCh->pTTY, &brkc, &brkf, 1 );
pCh->pTTY->real_raw = tmp;
}
#endif /* NEVER_HAPPENS_AS_SETUP_XXX */
diff --git a/drivers/char/n_hdlc.c b/drivers/char/n_hdlc.c
index a35bfd7ee80e..ed4e03333ab4 100644
--- a/drivers/char/n_hdlc.c
+++ b/drivers/char/n_hdlc.c
@@ -199,7 +199,7 @@ static void n_hdlc_tty_wakeup(struct tty_struct *tty);
#define tty2n_hdlc(tty) ((struct n_hdlc *) ((tty)->disc_data))
#define n_hdlc2tty(n_hdlc) ((n_hdlc)->tty)
-static struct tty_ldisc n_hdlc_ldisc = {
+static struct tty_ldisc_ops n_hdlc_ldisc = {
.owner = THIS_MODULE,
.magic = TTY_LDISC_MAGIC,
.name = "hdlc",
@@ -342,8 +342,8 @@ static int n_hdlc_tty_open (struct tty_struct *tty)
#endif
/* Flush any pending characters in the driver and discipline. */
- if (tty->ldisc.flush_buffer)
- tty->ldisc.flush_buffer(tty);
+ if (tty->ldisc.ops->flush_buffer)
+ tty->ldisc.ops->flush_buffer(tty);
tty_driver_flush_buffer(tty);
diff --git a/drivers/char/n_r3964.c b/drivers/char/n_r3964.c
index 902169062332..ae377aa473ba 100644
--- a/drivers/char/n_r3964.c
+++ b/drivers/char/n_r3964.c
@@ -143,7 +143,7 @@ static unsigned int r3964_poll(struct tty_struct *tty, struct file *file,
static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp,
char *fp, int count);
-static struct tty_ldisc tty_ldisc_N_R3964 = {
+static struct tty_ldisc_ops tty_ldisc_N_R3964 = {
.owner = THIS_MODULE,
.magic = TTY_LDISC_MAGIC,
.name = "R3964",
diff --git a/drivers/char/n_tty.c b/drivers/char/n_tty.c
index 8096389b0dc2..708c2b1dbe51 100644
--- a/drivers/char/n_tty.c
+++ b/drivers/char/n_tty.c
@@ -1573,7 +1573,7 @@ static unsigned int normal_poll(struct tty_struct *tty, struct file *file,
return mask;
}
-struct tty_ldisc tty_ldisc_N_TTY = {
+struct tty_ldisc_ops tty_ldisc_N_TTY = {
.magic = TTY_LDISC_MAGIC,
.name = "n_tty",
.open = n_tty_open,
diff --git a/drivers/char/pcmcia/synclink_cs.c b/drivers/char/pcmcia/synclink_cs.c
index 1dd0e992c83d..95743e2682fe 100644
--- a/drivers/char/pcmcia/synclink_cs.c
+++ b/drivers/char/pcmcia/synclink_cs.c
@@ -514,8 +514,8 @@ static void ldisc_receive_buf(struct tty_struct *tty,
return;
ld = tty_ldisc_ref(tty);
if (ld) {
- if (ld->receive_buf)
- ld->receive_buf(tty, data, flags, count);
+ if (ld->ops->receive_buf)
+ ld->ops->receive_buf(tty, data, flags, count);
tty_ldisc_deref(ld);
}
}
diff --git a/drivers/char/pty.c b/drivers/char/pty.c
index 0a05c038ae6f..76b27932d229 100644
--- a/drivers/char/pty.c
+++ b/drivers/char/pty.c
@@ -111,7 +111,7 @@ static int pty_write(struct tty_struct * tty, const unsigned char *buf, int coun
c = to->receive_room;
if (c > count)
c = count;
- to->ldisc.receive_buf(to, buf, NULL, c);
+ to->ldisc.ops->receive_buf(to, buf, NULL, c);
return c;
}
@@ -149,11 +149,11 @@ static int pty_chars_in_buffer(struct tty_struct *tty)
int count;
/* We should get the line discipline lock for "tty->link" */
- if (!to || !to->ldisc.chars_in_buffer)
+ if (!to || !to->ldisc.ops->chars_in_buffer)
return 0;
/* The ldisc must report 0 if no characters available to be read */
- count = to->ldisc.chars_in_buffer(to);
+ count = to->ldisc.ops->chars_in_buffer(to);
if (tty->driver->subtype == PTY_TYPE_SLAVE) return count;
@@ -186,8 +186,8 @@ static void pty_flush_buffer(struct tty_struct *tty)
if (!to)
return;
- if (to->ldisc.flush_buffer)
- to->ldisc.flush_buffer(to);
+ if (to->ldisc.ops->flush_buffer)
+ to->ldisc.ops->flush_buffer(to);
if (to->packet) {
spin_lock_irqsave(&tty->ctrl_lock, flags);
diff --git a/drivers/char/selection.c b/drivers/char/selection.c
index d63f5ccc29e6..2978a49a172b 100644
--- a/drivers/char/selection.c
+++ b/drivers/char/selection.c
@@ -327,7 +327,8 @@ int paste_selection(struct tty_struct *tty)
}
count = sel_buffer_lth - pasted;
count = min(count, tty->receive_room);
- tty->ldisc.receive_buf(tty, sel_buffer + pasted, NULL, count);
+ tty->ldisc.ops->receive_buf(tty, sel_buffer + pasted,
+ NULL, count);
pasted += count;
}
remove_wait_queue(&vc->paste_wait, &wait);
diff --git a/drivers/char/synclink.c b/drivers/char/synclink.c
index ac5080df2565..5e4b2e638d0c 100644
--- a/drivers/char/synclink.c
+++ b/drivers/char/synclink.c
@@ -975,8 +975,8 @@ static void ldisc_receive_buf(struct tty_struct *tty,
return;
ld = tty_ldisc_ref(tty);
if (ld) {
- if (ld->receive_buf)
- ld->receive_buf(tty, data, flags, count);
+ if (ld->ops->receive_buf)
+ ld->ops->receive_buf(tty, data, flags, count);
tty_ldisc_deref(ld);
}
}
diff --git a/drivers/char/synclink_gt.c b/drivers/char/synclink_gt.c
index 55c1653be00c..e473778cd6fa 100644
--- a/drivers/char/synclink_gt.c
+++ b/drivers/char/synclink_gt.c
@@ -641,8 +641,8 @@ static void ldisc_receive_buf(struct tty_struct *tty,
return;
ld = tty_ldisc_ref(tty);
if (ld) {
- if (ld->receive_buf)
- ld->receive_buf(tty, data, flags, count);
+ if (ld->ops->receive_buf)
+ ld->ops->receive_buf(tty, data, flags, count);
tty_ldisc_deref(ld);
}
}
diff --git a/drivers/char/synclinkmp.c b/drivers/char/synclinkmp.c
index bec54866e0bb..5341b5aaf8bc 100644
--- a/drivers/char/synclinkmp.c
+++ b/drivers/char/synclinkmp.c
@@ -712,8 +712,8 @@ static void ldisc_receive_buf(struct tty_struct *tty,
return;
ld = tty_ldisc_ref(tty);
if (ld) {
- if (ld->receive_buf)
- ld->receive_buf(tty, data, flags, count);
+ if (ld->ops->receive_buf)
+ ld->ops->receive_buf(tty, data, flags, count);
tty_ldisc_deref(ld);
}
}
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 047a17339f83..54c4ada460ee 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -95,8 +95,9 @@
#include <linux/wait.h>
#include <linux/bitops.h>
#include <linux/delay.h>
+#include <linux/seq_file.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
#include <asm/system.h>
#include <linux/kbd_kern.h>
@@ -682,7 +683,7 @@ static void tty_set_termios_ldisc(struct tty_struct *tty, int num)
static DEFINE_SPINLOCK(tty_ldisc_lock);
static DECLARE_WAIT_QUEUE_HEAD(tty_ldisc_wait);
/* Line disc dispatch table */
-static struct tty_ldisc tty_ldiscs[NR_LDISCS];
+static struct tty_ldisc_ops *tty_ldiscs[NR_LDISCS];
/**
* tty_register_ldisc - install a line discipline
@@ -697,7 +698,7 @@ static struct tty_ldisc tty_ldiscs[NR_LDISCS];
* takes tty_ldisc_lock to guard against ldisc races
*/
-int tty_register_ldisc(int disc, struct tty_ldisc *new_ldisc)
+int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc)
{
unsigned long flags;
int ret = 0;
@@ -706,10 +707,9 @@ int tty_register_ldisc(int disc, struct tty_ldisc *new_ldisc)
return -EINVAL;
spin_lock_irqsave(&tty_ldisc_lock, flags);
- tty_ldiscs[disc] = *new_ldisc;
- tty_ldiscs[disc].num = disc;
- tty_ldiscs[disc].flags |= LDISC_FLAG_DEFINED;
- tty_ldiscs[disc].refcount = 0;
+ tty_ldiscs[disc] = new_ldisc;
+ new_ldisc->num = disc;
+ new_ldisc->refcount = 0;
spin_unlock_irqrestore(&tty_ldisc_lock, flags);
return ret;
@@ -737,19 +737,56 @@ int tty_unregister_ldisc(int disc)
return -EINVAL;
spin_lock_irqsave(&tty_ldisc_lock, flags);
- if (tty_ldiscs[disc].refcount)
+ if (tty_ldiscs[disc]->refcount)
ret = -EBUSY;
else
- tty_ldiscs[disc].flags &= ~LDISC_FLAG_DEFINED;
+ tty_ldiscs[disc] = NULL;
spin_unlock_irqrestore(&tty_ldisc_lock, flags);
return ret;
}
EXPORT_SYMBOL(tty_unregister_ldisc);
+
+/**
+ * tty_ldisc_try_get - try and reference an ldisc
+ * @disc: ldisc number
+ * @ld: tty ldisc structure to complete
+ *
+ * Attempt to open and lock a line discipline into place. Return
+ * the line discipline refcounted and assigned in ld. On an error
+ * report the error code back
+ */
+
+static int tty_ldisc_try_get(int disc, struct tty_ldisc *ld)
+{
+ unsigned long flags;
+ struct tty_ldisc_ops *ldops;
+ int err = -EINVAL;
+
+ spin_lock_irqsave(&tty_ldisc_lock, flags);
+ ld->ops = NULL;
+ ldops = tty_ldiscs[disc];
+ /* Check the entry is defined */
+ if (ldops) {
+ /* If the module is being unloaded we can't use it */
+ if (!try_module_get(ldops->owner))
+ err = -EAGAIN;
+ else {
+ /* lock it */
+ ldops->refcount++;
+ ld->ops = ldops;
+ err = 0;
+ }
+ }
+ spin_unlock_irqrestore(&tty_ldisc_lock, flags);
+ return err;
+}
+
/**
* tty_ldisc_get - take a reference to an ldisc
* @disc: ldisc number
+ * @ld: tty line discipline structure to use
*
* Takes a reference to a line discipline. Deals with refcounts and
* module locking counts. Returns NULL if the discipline is not available.
@@ -760,32 +797,20 @@ EXPORT_SYMBOL(tty_unregister_ldisc);
* takes tty_ldisc_lock to guard against ldisc races
*/
-struct tty_ldisc *tty_ldisc_get(int disc)
+static int tty_ldisc_get(int disc, struct tty_ldisc *ld)
{
- unsigned long flags;
- struct tty_ldisc *ld;
+ int err;
if (disc < N_TTY || disc >= NR_LDISCS)
- return NULL;
-
- spin_lock_irqsave(&tty_ldisc_lock, flags);
-
- ld = &tty_ldiscs[disc];
- /* Check the entry is defined */
- if (ld->flags & LDISC_FLAG_DEFINED) {
- /* If the module is being unloaded we can't use it */
- if (!try_module_get(ld->owner))
- ld = NULL;
- else /* lock it */
- ld->refcount++;
- } else
- ld = NULL;
- spin_unlock_irqrestore(&tty_ldisc_lock, flags);
- return ld;
+ return -EINVAL;
+ err = tty_ldisc_try_get(disc, ld);
+ if (err == -EAGAIN) {
+ request_module("tty-ldisc-%d", disc);
+ err = tty_ldisc_try_get(disc, ld);
+ }
+ return err;
}
-EXPORT_SYMBOL_GPL(tty_ldisc_get);
-
/**
* tty_ldisc_put - drop ldisc reference
* @disc: ldisc number
@@ -797,22 +822,67 @@ EXPORT_SYMBOL_GPL(tty_ldisc_get);
* takes tty_ldisc_lock to guard against ldisc races
*/
-void tty_ldisc_put(int disc)
+static void tty_ldisc_put(struct tty_ldisc_ops *ld)
{
- struct tty_ldisc *ld;
unsigned long flags;
+ int disc = ld->num;
BUG_ON(disc < N_TTY || disc >= NR_LDISCS);
spin_lock_irqsave(&tty_ldisc_lock, flags);
- ld = &tty_ldiscs[disc];
+ ld = tty_ldiscs[disc];
BUG_ON(ld->refcount == 0);
ld->refcount--;
module_put(ld->owner);
spin_unlock_irqrestore(&tty_ldisc_lock, flags);
}
-EXPORT_SYMBOL_GPL(tty_ldisc_put);
+static void * tty_ldiscs_seq_start(struct seq_file *m, loff_t *pos)
+{
+ return (*pos < NR_LDISCS) ? pos : NULL;
+}
+
+static void * tty_ldiscs_seq_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ (*pos)++;
+ return (*pos < NR_LDISCS) ? pos : NULL;
+}
+
+static void tty_ldiscs_seq_stop(struct seq_file *m, void *v)
+{
+}
+
+static int tty_ldiscs_seq_show(struct seq_file *m, void *v)
+{
+ int i = *(loff_t *)v;
+ struct tty_ldisc ld;
+
+ if (tty_ldisc_get(i, &ld) < 0)
+ return 0;
+ seq_printf(m, "%-10s %2d\n", ld.ops->name ? ld.ops->name : "???", i);
+ tty_ldisc_put(ld.ops);
+ return 0;
+}
+
+static const struct seq_operations tty_ldiscs_seq_ops = {
+ .start = tty_ldiscs_seq_start,
+ .next = tty_ldiscs_seq_next,
+ .stop = tty_ldiscs_seq_stop,
+ .show = tty_ldiscs_seq_show,
+};
+
+static int proc_tty_ldiscs_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &tty_ldiscs_seq_ops);
+}
+
+const struct file_operations tty_ldiscs_proc_fops = {
+ .owner = THIS_MODULE,
+ .open = proc_tty_ldiscs_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
/**
* tty_ldisc_assign - set ldisc on a tty
@@ -829,8 +899,8 @@ EXPORT_SYMBOL_GPL(tty_ldisc_put);
static void tty_ldisc_assign(struct tty_struct *tty, struct tty_ldisc *ld)
{
+ ld->refcount = 0;
tty->ldisc = *ld;
- tty->ldisc.refcount = 0;
}
/**
@@ -954,6 +1024,41 @@ static void tty_ldisc_enable(struct tty_struct *tty)
}
/**
+ * tty_ldisc_restore - helper for tty ldisc change
+ * @tty: tty to recover
+ * @old: previous ldisc
+ *
+ * Restore the previous line discipline or N_TTY when a line discipline
+ * change fails due to an open error
+ */
+
+static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old)
+{
+ char buf[64];
+ struct tty_ldisc new_ldisc;
+
+ /* There is an outstanding reference here so this is safe */
+ tty_ldisc_get(old->ops->num, old);
+ tty_ldisc_assign(tty, old);
+ tty_set_termios_ldisc(tty, old->ops->num);
+ if (old->ops->open && (old->ops->open(tty) < 0)) {
+ tty_ldisc_put(old->ops);
+ /* This driver is always present */
+ if (tty_ldisc_get(N_TTY, &new_ldisc) < 0)
+ panic("n_tty: get");
+ tty_ldisc_assign(tty, &new_ldisc);
+ tty_set_termios_ldisc(tty, N_TTY);
+ if (new_ldisc.ops->open) {
+ int r = new_ldisc.ops->open(tty);
+ if (r < 0)
+ panic("Couldn't open N_TTY ldisc for "
+ "%s --- error %d.",
+ tty_name(tty, buf), r);
+ }
+ }
+}
+
+/**
* tty_set_ldisc - set line discipline
* @tty: the terminal to set
* @ldisc: the line discipline
@@ -967,28 +1072,18 @@ static void tty_ldisc_enable(struct tty_struct *tty)
static int tty_set_ldisc(struct tty_struct *tty, int ldisc)
{
- int retval = 0;
- struct tty_ldisc o_ldisc;
- char buf[64];
+ int retval;
+ struct tty_ldisc o_ldisc, new_ldisc;
int work;
unsigned long flags;
- struct tty_ldisc *ld;
struct tty_struct *o_tty;
- if ((ldisc < N_TTY) || (ldisc >= NR_LDISCS))
- return -EINVAL;
-
restart:
-
- ld = tty_ldisc_get(ldisc);
- /* Eduardo Blanco <ejbs@cs.cs.com.uy> */
- /* Cyrus Durgin <cider@speakeasy.org> */
- if (ld == NULL) {
- request_module("tty-ldisc-%d", ldisc);
- ld = tty_ldisc_get(ldisc);
- }
- if (ld == NULL)
- return -EINVAL;
+ /* This is a bit ugly for now but means we can break the 'ldisc
+ is part of the tty struct' assumption later */
+ retval = tty_ldisc_get(ldisc, &new_ldisc);
+ if (retval)
+ return retval;
/*
* Problem: What do we do if this blocks ?
@@ -996,8 +1091,8 @@ restart:
tty_wait_until_sent(tty, 0);
- if (tty->ldisc.num == ldisc) {
- tty_ldisc_put(ldisc);
+ if (tty->ldisc.ops->num == ldisc) {
+ tty_ldisc_put(new_ldisc.ops);
return 0;
}
@@ -1024,7 +1119,7 @@ restart:
/* Free the new ldisc we grabbed. Must drop the lock
first. */
spin_unlock_irqrestore(&tty_ldisc_lock, flags);
- tty_ldisc_put(ldisc);
+ tty_ldisc_put(o_ldisc.ops);
/*
* There are several reasons we may be busy, including
* random momentary I/O traffic. We must therefore
@@ -1038,7 +1133,7 @@ restart:
}
if (o_tty && o_tty->ldisc.refcount) {
spin_unlock_irqrestore(&tty_ldisc_lock, flags);
- tty_ldisc_put(ldisc);
+ tty_ldisc_put(o_tty->ldisc.ops);
if (wait_event_interruptible(tty_ldisc_wait, o_tty->ldisc.refcount == 0) < 0)
return -ERESTARTSYS;
goto restart;
@@ -1049,8 +1144,9 @@ restart:
* another ldisc change
*/
if (!test_bit(TTY_LDISC, &tty->flags)) {
+ struct tty_ldisc *ld;
spin_unlock_irqrestore(&tty_ldisc_lock, flags);
- tty_ldisc_put(ldisc);
+ tty_ldisc_put(new_ldisc.ops);
ld = tty_ldisc_ref_wait(tty);
tty_ldisc_deref(ld);
goto restart;
@@ -1060,7 +1156,7 @@ restart:
if (o_tty)
clear_bit(TTY_LDISC, &o_tty->flags);
spin_unlock_irqrestore(&tty_ldisc_lock, flags);
-
+
/*
* From this point on we know nobody has an ldisc
* usage reference, nor can they obtain one until
@@ -1070,45 +1166,30 @@ restart:
work = cancel_delayed_work(&tty->buf.work);
/*
* Wait for ->hangup_work and ->buf.work handlers to terminate
+ * MUST NOT hold locks here.
*/
flush_scheduled_work();
/* Shutdown the current discipline. */
- if (tty->ldisc.close)
- (tty->ldisc.close)(tty);
+ if (o_ldisc.ops->close)
+ (o_ldisc.ops->close)(tty);
/* Now set up the new line discipline. */
- tty_ldisc_assign(tty, ld);
+ tty_ldisc_assign(tty, &new_ldisc);
tty_set_termios_ldisc(tty, ldisc);
- if (tty->ldisc.open)
- retval = (tty->ldisc.open)(tty);
+ if (new_ldisc.ops->open)
+ retval = (new_ldisc.ops->open)(tty);
if (retval < 0) {
- tty_ldisc_put(ldisc);
- /* There is an outstanding reference here so this is safe */
- tty_ldisc_assign(tty, tty_ldisc_get(o_ldisc.num));
- tty_set_termios_ldisc(tty, tty->ldisc.num);
- if (tty->ldisc.open && (tty->ldisc.open(tty) < 0)) {
- tty_ldisc_put(o_ldisc.num);
- /* This driver is always present */
- tty_ldisc_assign(tty, tty_ldisc_get(N_TTY));
- tty_set_termios_ldisc(tty, N_TTY);
- if (tty->ldisc.open) {
- int r = tty->ldisc.open(tty);
-
- if (r < 0)
- panic("Couldn't open N_TTY ldisc for "
- "%s --- error %d.",
- tty_name(tty, buf), r);
- }
- }
+ tty_ldisc_put(new_ldisc.ops);
+ tty_ldisc_restore(tty, &o_ldisc);
}
/* At this point we hold a reference to the new ldisc and a
a reference to the old ldisc. If we ended up flipping back
to the existing ldisc we have two references to it */
- if (tty->ldisc.num != o_ldisc.num && tty->ops->set_ldisc)
+ if (tty->ldisc.ops->num != o_ldisc.ops->num && tty->ops->set_ldisc)
tty->ops->set_ldisc(tty);
- tty_ldisc_put(o_ldisc.num);
+ tty_ldisc_put(o_ldisc.ops);
/*
* Allow ldisc referencing to occur as soon as the driver
@@ -1335,8 +1416,8 @@ void tty_wakeup(struct tty_struct *tty)
if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) {
ld = tty_ldisc_ref(tty);
if (ld) {
- if (ld->write_wakeup)
- ld->write_wakeup(tty);
+ if (ld->ops->write_wakeup)
+ ld->ops->write_wakeup(tty);
tty_ldisc_deref(ld);
}
}
@@ -1357,8 +1438,8 @@ void tty_ldisc_flush(struct tty_struct *tty)
{
struct tty_ldisc *ld = tty_ldisc_ref(tty);
if (ld) {
- if (ld->flush_buffer)
- ld->flush_buffer(tty);
+ if (ld->ops->flush_buffer)
+ ld->ops->flush_buffer(tty);
tty_ldisc_deref(ld);
}
tty_buffer_flush(tty);
@@ -1386,7 +1467,7 @@ static void tty_reset_termios(struct tty_struct *tty)
* do_tty_hangup - actual handler for hangup events
* @work: tty device
*
- * This can be called by the "eventd" kernel thread. That is process
+k * This can be called by the "eventd" kernel thread. That is process
* synchronous but doesn't hold any locks, so we need to make sure we
* have the appropriate locks for what we're doing.
*
@@ -1449,14 +1530,14 @@ static void do_tty_hangup(struct work_struct *work)
ld = tty_ldisc_ref(tty);
if (ld != NULL) {
/* We may have no line discipline at this point */
- if (ld->flush_buffer)
- ld->flush_buffer(tty);
+ if (ld->ops->flush_buffer)
+ ld->ops->flush_buffer(tty);
tty_driver_flush_buffer(tty);
if ((test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) &&
- ld->write_wakeup)
- ld->write_wakeup(tty);
- if (ld->hangup)
- ld->hangup(tty);
+ ld->ops->write_wakeup)
+ ld->ops->write_wakeup(tty);
+ if (ld->ops->hangup)
+ ld->ops->hangup(tty);
}
/*
* FIXME: Once we trust the LDISC code better we can wait here for
@@ -1825,8 +1906,8 @@ static ssize_t tty_read(struct file *file, char __user *buf, size_t count,
/* We want to wait for the line discipline to sort out in this
situation */
ld = tty_ldisc_ref_wait(tty);
- if (ld->read)
- i = (ld->read)(tty, file, buf, count);
+ if (ld->ops->read)
+ i = (ld->ops->read)(tty, file, buf, count);
else
i = -EIO;
tty_ldisc_deref(ld);
@@ -1978,10 +2059,10 @@ static ssize_t tty_write(struct file *file, const char __user *buf,
printk(KERN_ERR "tty driver %s lacks a write_room method.\n",
tty->driver->name);
ld = tty_ldisc_ref_wait(tty);
- if (!ld->write)
+ if (!ld->ops->write)
ret = -EIO;
else
- ret = do_tty_write(ld->write, tty, file, buf, count);
+ ret = do_tty_write(ld->ops->write, tty, file, buf, count);
tty_ldisc_deref(ld);
return ret;
}
@@ -2076,6 +2157,7 @@ static int init_dev(struct tty_driver *driver, int idx,
struct ktermios *tp, **tp_loc, *o_tp, **o_tp_loc;
struct ktermios *ltp, **ltp_loc, *o_ltp, **o_ltp_loc;
int retval = 0;
+ struct tty_ldisc *ld;
/* check whether we're reopening an existing tty */
if (driver->flags & TTY_DRIVER_DEVPTS_MEM) {
@@ -2224,17 +2306,19 @@ static int init_dev(struct tty_driver *driver, int idx,
* If we fail here just call release_tty to clean up. No need
* to decrement the use counts, as release_tty doesn't care.
*/
+
+ ld = &tty->ldisc;
- if (tty->ldisc.open) {
- retval = (tty->ldisc.open)(tty);
+ if (ld->ops->open) {
+ retval = (ld->ops->open)(tty);
if (retval)
goto release_mem_out;
}
- if (o_tty && o_tty->ldisc.open) {
- retval = (o_tty->ldisc.open)(o_tty);
+ if (o_tty && o_tty->ldisc.ops->open) {
+ retval = (o_tty->ldisc.ops->open)(o_tty);
if (retval) {
- if (tty->ldisc.close)
- (tty->ldisc.close)(tty);
+ if (ld->ops->close)
+ (ld->ops->close)(tty);
goto release_mem_out;
}
tty_ldisc_enable(o_tty);
@@ -2378,6 +2462,7 @@ static void release_tty(struct tty_struct *tty, int idx)
static void release_dev(struct file *filp)
{
struct tty_struct *tty, *o_tty;
+ struct tty_ldisc ld;
int pty_master, tty_closing, o_tty_closing, do_sleep;
int devpts;
int idx;
@@ -2611,26 +2696,27 @@ static void release_dev(struct file *filp)
spin_unlock_irqrestore(&tty_ldisc_lock, flags);
/*
* Shutdown the current line discipline, and reset it to N_TTY.
- * N.B. why reset ldisc when we're releasing the memory??
*
* FIXME: this MUST get fixed for the new reflocking
*/
- if (tty->ldisc.close)
- (tty->ldisc.close)(tty);
- tty_ldisc_put(tty->ldisc.num);
+ if (tty->ldisc.ops->close)
+ (tty->ldisc.ops->close)(tty);
+ tty_ldisc_put(tty->ldisc.ops);
/*
* Switch the line discipline back
*/
- tty_ldisc_assign(tty, tty_ldisc_get(N_TTY));
+ WARN_ON(tty_ldisc_get(N_TTY, &ld));
+ tty_ldisc_assign(tty, &ld);
tty_set_termios_ldisc(tty, N_TTY);
if (o_tty) {
/* FIXME: could o_tty be in setldisc here ? */
clear_bit(TTY_LDISC, &o_tty->flags);
- if (o_tty->ldisc.close)
- (o_tty->ldisc.close)(o_tty);
- tty_ldisc_put(o_tty->ldisc.num);
- tty_ldisc_assign(o_tty, tty_ldisc_get(N_TTY));
+ if (o_tty->ldisc.ops->close)
+ (o_tty->ldisc.ops->close)(o_tty);
+ tty_ldisc_put(o_tty->ldisc.ops);
+ WARN_ON(tty_ldisc_get(N_TTY, &ld));
+ tty_ldisc_assign(o_tty, &ld);
tty_set_termios_ldisc(o_tty, N_TTY);
}
/*
@@ -2899,8 +2985,8 @@ static unsigned int tty_poll(struct file *filp, poll_table *wait)
return 0;
ld = tty_ldisc_ref_wait(tty);
- if (ld->poll)
- ret = (ld->poll)(tty, filp, wait);
+ if (ld->ops->poll)
+ ret = (ld->ops->poll)(tty, filp, wait);
tty_ldisc_deref(ld);
return ret;
}
@@ -2974,7 +3060,7 @@ static int tiocsti(struct tty_struct *tty, char __user *p)
if (get_user(ch, p))
return -EFAULT;
ld = tty_ldisc_ref_wait(tty);
- ld->receive_buf(tty, &ch, &mbz, 1);
+ ld->ops->receive_buf(tty, &ch, &mbz, 1);
tty_ldisc_deref(ld);
return 0;
}
@@ -3528,7 +3614,7 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
case TIOCGSID:
return tiocgsid(tty, real_tty, p);
case TIOCGETD:
- return put_user(tty->ldisc.num, (int __user *)p);
+ return put_user(tty->ldisc.ops->num, (int __user *)p);
case TIOCSETD:
return tiocsetd(tty, p);
#ifdef CONFIG_VT
@@ -3581,8 +3667,8 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
}
ld = tty_ldisc_ref_wait(tty);
retval = -EINVAL;
- if (ld->ioctl) {
- retval = ld->ioctl(tty, file, cmd, arg);
+ if (ld->ops->ioctl) {
+ retval = ld->ops->ioctl(tty, file, cmd, arg);
if (retval == -ENOIOCTLCMD)
retval = -EINVAL;
}
@@ -3609,8 +3695,8 @@ static long tty_compat_ioctl(struct file *file, unsigned int cmd,
}
ld = tty_ldisc_ref_wait(tty);
- if (ld->compat_ioctl)
- retval = ld->compat_ioctl(tty, file, cmd, arg);
+ if (ld->ops->compat_ioctl)
+ retval = ld->ops->compat_ioctl(tty, file, cmd, arg);
tty_ldisc_deref(ld);
return retval;
@@ -3782,7 +3868,8 @@ static void flush_to_ldisc(struct work_struct *work)
flag_buf = head->flag_buf_ptr + head->read;
head->read += count;
spin_unlock_irqrestore(&tty->buf.lock, flags);
- disc->receive_buf(tty, char_buf, flag_buf, count);
+ disc->ops->receive_buf(tty, char_buf,
+ flag_buf, count);
spin_lock_irqsave(&tty->buf.lock, flags);
}
/* Restore the queue head */
@@ -3843,9 +3930,12 @@ EXPORT_SYMBOL(tty_flip_buffer_push);
static void initialize_tty_struct(struct tty_struct *tty)
{
+ struct tty_ldisc ld;
memset(tty, 0, sizeof(struct tty_struct));
tty->magic = TTY_MAGIC;
- tty_ldisc_assign(tty, tty_ldisc_get(N_TTY));
+ if (tty_ldisc_get(N_TTY, &ld) < 0)
+ panic("n_tty: init_tty");
+ tty_ldisc_assign(tty, &ld);
tty->session = NULL;
tty->pgrp = NULL;
tty->overrun_time = jiffies;
diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c
index 8f81139d6194..ea9fc5d03b99 100644
--- a/drivers/char/tty_ioctl.c
+++ b/drivers/char/tty_ioctl.c
@@ -491,8 +491,8 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios)
ld = tty_ldisc_ref(tty);
if (ld != NULL) {
- if (ld->set_termios)
- (ld->set_termios)(tty, &old_termios);
+ if (ld->ops->set_termios)
+ (ld->ops->set_termios)(tty, &old_termios);
tty_ldisc_deref(ld);
}
mutex_unlock(&tty->termios_mutex);
@@ -552,8 +552,8 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
ld = tty_ldisc_ref(tty);
if (ld != NULL) {
- if ((opt & TERMIOS_FLUSH) && ld->flush_buffer)
- ld->flush_buffer(tty);
+ if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
+ ld->ops->flush_buffer(tty);
tty_ldisc_deref(ld);
}
@@ -959,12 +959,12 @@ int tty_perform_flush(struct tty_struct *tty, unsigned long arg)
ld = tty_ldisc_ref(tty);
switch (arg) {
case TCIFLUSH:
- if (ld && ld->flush_buffer)
- ld->flush_buffer(tty);
+ if (ld && ld->ops->flush_buffer)
+ ld->ops->flush_buffer(tty);
break;
case TCIOFLUSH:
- if (ld && ld->flush_buffer)
- ld->flush_buffer(tty);
+ if (ld && ld->ops->flush_buffer)
+ ld->ops->flush_buffer(tty);
/* fall through */
case TCOFLUSH:
tty_driver_flush_buffer(tty);
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-17 16:11:53 +0000