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tty/serial: lay the foundations for the next set of reworks

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- Stop drivers calling their own flush method indirectly, it obfuscates code
  and it will change soon anyway

- A few more lock_kernel paths temporarily needed in some driver internal
  waiting code

- Remove private put_char method that does a write call for one char - we
  have that anyway

- Most but not yet all of the termios copy under lock fixing (some has other
  dependencies to follow)

- Note a few locking bugs in drivers found in the process

- Kill remaining [ab]users of TIOCG/SSOFTCAR in the driver, these must go to
  fix the termios locking

Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Alan Cox
2008-04-30 00:53:59 -07:00
committed by Linus Torvalds
parent ac0e4b7d31
commit 978e595f88
26 changed files with 189 additions and 234 deletions
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76
drivers/char/cyclades.c
View File

@@ -2522,6 +2522,7 @@ static void cy_wait_until_sent(struct tty_struct *tty, int timeout)
return; /* Just in case.... */
orig_jiffies = jiffies;
lock_kernel();
/*
* Set the check interval to be 1/5 of the estimated time to
* send a single character, and make it at least 1. The check
@@ -2573,11 +2574,47 @@ static void cy_wait_until_sent(struct tty_struct *tty, int timeout)
}
/* Run one more char cycle */
msleep_interruptible(jiffies_to_msecs(char_time * 5));
unlock_kernel();
#ifdef CY_DEBUG_WAIT_UNTIL_SENT
printk(KERN_DEBUG "Clean (jiff=%lu)...done\n", jiffies);
#endif
}
static void cy_flush_buffer(struct tty_struct *tty)
{
struct cyclades_port *info = tty->driver_data;
struct cyclades_card *card;
int channel, retval;
unsigned long flags;
#ifdef CY_DEBUG_IO
printk(KERN_DEBUG "cyc:cy_flush_buffer ttyC%d\n", info->line);
#endif
if (serial_paranoia_check(info, tty->name, "cy_flush_buffer"))
return;
card = info->card;
channel = info->line - card->first_line;
spin_lock_irqsave(&card->card_lock, flags);
info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
spin_unlock_irqrestore(&card->card_lock, flags);
if (IS_CYC_Z(*card)) { /* If it is a Z card, flush the on-board
buffers as well */
spin_lock_irqsave(&card->card_lock, flags);
retval = cyz_issue_cmd(card, channel, C_CM_FLUSH_TX, 0L);
if (retval != 0) {
printk(KERN_ERR "cyc: flush_buffer retval on ttyC%d "
"was %x\n", info->line, retval);
}
spin_unlock_irqrestore(&card->card_lock, flags);
}
tty_wakeup(tty);
} /* cy_flush_buffer */
/*
* This routine is called when a particular tty device is closed.
*/
@@ -2689,8 +2726,7 @@ static void cy_close(struct tty_struct *tty, struct file *filp)
spin_unlock_irqrestore(&card->card_lock, flags);
shutdown(info);
if (tty->driver->flush_buffer)
tty->driver->flush_buffer(tty);
cy_flush_buffer(tty);
tty_ldisc_flush(tty);
spin_lock_irqsave(&card->card_lock, flags);
@@ -2881,6 +2917,7 @@ static int cy_chars_in_buffer(struct tty_struct *tty)
int char_count;
__u32 tx_put, tx_get, tx_bufsize;
lock_kernel();
firm_id = card->base_addr + ID_ADDRESS;
zfw_ctrl = card->base_addr +
(readl(&firm_id->zfwctrl_addr) & 0xfffff);
@@ -2898,6 +2935,7 @@ static int cy_chars_in_buffer(struct tty_struct *tty)
printk(KERN_DEBUG "cyc:cy_chars_in_buffer ttyC%d %d\n",
info->line, info->xmit_cnt + char_count);
#endif
unlock_kernel();
return info->xmit_cnt + char_count;
}
#endif /* Z_EXT_CHARS_IN_BUFFER */
@@ -4271,40 +4309,6 @@ static void cy_start(struct tty_struct *tty)
}
} /* cy_start */
static void cy_flush_buffer(struct tty_struct *tty)
{
struct cyclades_port *info = tty->driver_data;
struct cyclades_card *card;
int channel, retval;
unsigned long flags;
#ifdef CY_DEBUG_IO
printk(KERN_DEBUG "cyc:cy_flush_buffer ttyC%d\n", info->line);
#endif
if (serial_paranoia_check(info, tty->name, "cy_flush_buffer"))
return;
card = info->card;
channel = info->line - card->first_line;
spin_lock_irqsave(&card->card_lock, flags);
info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
spin_unlock_irqrestore(&card->card_lock, flags);
if (IS_CYC_Z(*card)) { /* If it is a Z card, flush the on-board
buffers as well */
spin_lock_irqsave(&card->card_lock, flags);
retval = cyz_issue_cmd(card, channel, C_CM_FLUSH_TX, 0L);
if (retval != 0) {
printk(KERN_ERR "cyc: flush_buffer retval on ttyC%d "
"was %x\n", info->line, retval);
}
spin_unlock_irqrestore(&card->card_lock, flags);
}
tty_wakeup(tty);
} /* cy_flush_buffer */
/*
* cy_hangup() --- called by tty_hangup() when a hangup is signaled.
*/