From: Jan Kiszka <jan.kiszka@web.de>
To: David Miller <davem@davemloft.net>, Karsten Keil <isdn@linux-pingi.de>
Cc: linux-kernel@vger.kernel.org,
i4ldeveloper@listserv.isdn4linux.de,
isdn4linux@listserv.isdn4linux.de, netdev@vger.kernel.org
Subject: [PATCH 21/31] CAPI: Remove useless checks for tty->driver_data or hung up state
Date: Fri, 8 Jan 2010 12:00:23 +0100 [thread overview]
Message-ID: <c9ce6c91b2b475a59d338a4e97620d704ccf6fb6.1264201407.git.jan.kiszka@web.de> (raw)
In-Reply-To: <cover.1264201406.git.jan.kiszka@web.de>
Remove more desperate attempts to fix races in the original code: As
long as the TTY is open, its driver_data cannot become NULL. And we
already call tty_hangup to signal the end of a connection, no need to
check for mp->nccip in addition.
Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
---
drivers/isdn/capi/capi.c | 80 ++++++++++++----------------------------------
1 files changed, 21 insertions(+), 59 deletions(-)
diff --git a/drivers/isdn/capi/capi.c b/drivers/isdn/capi/capi.c
index 7710a66..77faa4e 100644
--- a/drivers/isdn/capi/capi.c
+++ b/drivers/isdn/capi/capi.c
@@ -1017,7 +1017,7 @@ static void capinc_tty_close(struct tty_struct * tty, struct file * file)
static int capinc_tty_write(struct tty_struct * tty,
const unsigned char *buf, int count)
{
- struct capiminor *mp = (struct capiminor *)tty->driver_data;
+ struct capiminor *mp = tty->driver_data;
struct sk_buff *skb;
unsigned long flags;
@@ -1025,13 +1025,6 @@ static int capinc_tty_write(struct tty_struct * tty,
printk(KERN_DEBUG "capinc_tty_write(count=%d)n", count);
#endif
- if (!mp || !mp->nccip) {
-#ifdef _DEBUG_TTYFUNCS
- printk(KERN_DEBUG "capinc_tty_write: mp or mp->ncci NULLn");
-#endif
- return 0;
- }
-
spin_lock_irqsave(&workaround_lock, flags);
skb = mp->ttyskb;
if (skb) {
@@ -1060,7 +1053,7 @@ static int capinc_tty_write(struct tty_struct * tty,
static int capinc_tty_put_char(struct tty_struct *tty, unsigned char ch)
{
- struct capiminor *mp = (struct capiminor *)tty->driver_data;
+ struct capiminor *mp = tty->driver_data;
struct sk_buff *skb;
unsigned long flags;
int ret = 1;
@@ -1069,13 +1062,6 @@ static int capinc_tty_put_char(struct tty_struct *tty, unsigned char ch)
printk(KERN_DEBUG "capinc_put_char(%u)n", ch);
#endif
- if (!mp || !mp->nccip) {
-#ifdef _DEBUG_TTYFUNCS
- printk(KERN_DEBUG "capinc_tty_put_char: mp or mp->ncci NULLn");
-#endif
- return 0;
- }
-
spin_lock_irqsave(&workaround_lock, flags);
skb = mp->ttyskb;
if (skb) {
@@ -1104,7 +1090,7 @@ static int capinc_tty_put_char(struct tty_struct *tty, unsigned char ch)
static void capinc_tty_flush_chars(struct tty_struct *tty)
{
- struct capiminor *mp = (struct capiminor *)tty->driver_data;
+ struct capiminor *mp = tty->driver_data;
struct sk_buff *skb;
unsigned long flags;
@@ -1112,13 +1098,6 @@ static void capinc_tty_flush_chars(struct tty_struct *tty)
printk(KERN_DEBUG "capinc_tty_flush_charsn");
#endif
- if (!mp || !mp->nccip) {
-#ifdef _DEBUG_TTYFUNCS
- printk(KERN_DEBUG "capinc_tty_flush_chars: mp or mp->ncci NULLn");
-#endif
- return;
- }
-
spin_lock_irqsave(&workaround_lock, flags);
skb = mp->ttyskb;
if (skb) {
@@ -1133,14 +1112,9 @@ static void capinc_tty_flush_chars(struct tty_struct *tty)
static int capinc_tty_write_room(struct tty_struct *tty)
{
- struct capiminor *mp = (struct capiminor *)tty->driver_data;
+ struct capiminor *mp = tty->driver_data;
int room;
- if (!mp || !mp->nccip) {
-#ifdef _DEBUG_TTYFUNCS
- printk(KERN_DEBUG "capinc_tty_write_room: mp or mp->ncci NULLn");
-#endif
- return 0;
- }
+
room = CAPINC_MAX_SENDQUEUE-skb_queue_len(&mp->outqueue);
room *= CAPI_MAX_BLKSIZE;
#ifdef _DEBUG_TTYFUNCS
@@ -1151,13 +1125,8 @@ static int capinc_tty_write_room(struct tty_struct *tty)
static int capinc_tty_chars_in_buffer(struct tty_struct *tty)
{
- struct capiminor *mp = (struct capiminor *)tty->driver_data;
- if (!mp || !mp->nccip) {
-#ifdef _DEBUG_TTYFUNCS
- printk(KERN_DEBUG "capinc_tty_chars_in_buffer: mp or mp->ncci NULLn");
-#endif
- return 0;
- }
+ struct capiminor *mp = tty->driver_data;
+
#ifdef _DEBUG_TTYFUNCS
printk(KERN_DEBUG "capinc_tty_chars_in_buffer = %d nack=%d sq=%d rq=%dn",
mp->outbytes, mp->nack,
@@ -1188,53 +1157,46 @@ static void capinc_tty_set_termios(struct tty_struct *tty, struct ktermios * old
static void capinc_tty_throttle(struct tty_struct * tty)
{
- struct capiminor *mp = (struct capiminor *)tty->driver_data;
+ struct capiminor *mp = tty->driver_data;
#ifdef _DEBUG_TTYFUNCS
printk(KERN_DEBUG "capinc_tty_throttlen");
#endif
- if (mp)
- mp->ttyinstop = 1;
+ mp->ttyinstop = 1;
}
static void capinc_tty_unthrottle(struct tty_struct * tty)
{
- struct capiminor *mp = (struct capiminor *)tty->driver_data;
+ struct capiminor *mp = tty->driver_data;
unsigned long flags;
#ifdef _DEBUG_TTYFUNCS
printk(KERN_DEBUG "capinc_tty_unthrottlen");
#endif
- if (mp) {
- spin_lock_irqsave(&workaround_lock, flags);
- mp->ttyinstop = 0;
- handle_minor_recv(mp);
- spin_unlock_irqrestore(&workaround_lock, flags);
- }
+ spin_lock_irqsave(&workaround_lock, flags);
+ mp->ttyinstop = 0;
+ handle_minor_recv(mp);
+ spin_unlock_irqrestore(&workaround_lock, flags);
}
static void capinc_tty_stop(struct tty_struct *tty)
{
- struct capiminor *mp = (struct capiminor *)tty->driver_data;
+ struct capiminor *mp = tty->driver_data;
#ifdef _DEBUG_TTYFUNCS
printk(KERN_DEBUG "capinc_tty_stopn");
#endif
- if (mp) {
- mp->ttyoutstop = 1;
- }
+ mp->ttyoutstop = 1;
}
static void capinc_tty_start(struct tty_struct *tty)
{
- struct capiminor *mp = (struct capiminor *)tty->driver_data;
+ struct capiminor *mp = tty->driver_data;
unsigned long flags;
#ifdef _DEBUG_TTYFUNCS
printk(KERN_DEBUG "capinc_tty_startn");
#endif
- if (mp) {
- spin_lock_irqsave(&workaround_lock, flags);
- mp->ttyoutstop = 0;
- (void)handle_minor_send(mp);
- spin_unlock_irqrestore(&workaround_lock, flags);
- }
+ spin_lock_irqsave(&workaround_lock, flags);
+ mp->ttyoutstop = 0;
+ (void)handle_minor_send(mp);
+ spin_unlock_irqrestore(&workaround_lock, flags);
}
static void capinc_tty_hangup(struct tty_struct *tty)
--
1.6.0.2
next prev parent reply other threads:[~2010-01-22 23:29 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-22 23:03 [PATCH 00/31] CAPI: Major rework, tons of bug fixes Jan Kiszka
2010-01-06 10:43 ` [PATCH 01/31] CAPI: Fix leaks in capifs_new_ncci Jan Kiszka
2010-01-06 10:47 ` [PATCH 05/31] CAPI: Reduce chattiness during module loading/removal Jan Kiszka
2010-01-06 13:38 ` [PATCH 02/31] CAPI: Sanitize capifs API Jan Kiszka
2010-01-06 13:49 ` [PATCH 03/31] CAPI: Eliminate capifs_root variable Jan Kiszka
2010-01-06 14:03 ` [PATCH 04/31] CAPI: Pin capifs instead of mounting it Jan Kiszka
2010-01-06 18:02 ` [PATCH 07/31] CAPI: Convert capi drivers rwlock into mutex Jan Kiszka
2010-01-06 18:55 ` [PATCH 06/31] CAPI: Call a controller 'controller', not 'card' Jan Kiszka
2010-01-07 10:53 ` [PATCH 08/31] CAPI: Rework capi_ctr_ready/down Jan Kiszka
2010-01-07 11:04 ` [PATCH 10/31] CAPI: Rework locking of controller data structures Jan Kiszka
2010-01-07 12:36 ` [PATCH 11/31] CAPI: Rework application locking Jan Kiszka
2010-01-07 17:42 ` [PATCH 12/31] CAPI: Reduce #ifdef mess around CONFIG_ISDN_CAPI_MIDDLEWARE Jan Kiszka
2010-01-07 18:16 ` [PATCH 13/31] CAPI: Convert capidev_list_lock into a mutex Jan Kiszka
2010-01-07 18:24 ` [PATCH 14/31] CAPI: Clean up capi_open/release Jan Kiszka
2010-01-07 19:12 ` [PATCH 15/31] CAPI: Rework locking of capidev members Jan Kiszka
2010-01-07 19:21 ` [PATCH 16/31] CAPI: Use non-atomic allocation during NCCI setup Jan Kiszka
2010-01-07 19:38 ` [PATCH 17/31] CAPI: Fix racy capi_read Jan Kiszka
2010-01-07 20:52 ` [PATCH 18/31] CAPI: Switch NCCI list to standard doubly linked list Jan Kiszka
2010-01-08 9:45 ` [PATCH 19/31] CAPI: Fix locking around glueing capiminor and capidev Jan Kiszka
2010-01-08 10:38 ` [PATCH 20/31] CAPI: Drop atomic ttyopencount Jan Kiszka
2010-01-08 11:00 ` Jan Kiszka [this message]
2010-01-08 11:39 ` [PATCH 23/31] CAPI: Rename datahandle_queue -> ackqueue_entry Jan Kiszka
2010-01-08 11:46 ` [PATCH 24/31] CAPI: Use atomics for capiminor's datahandle and msgid Jan Kiszka
2010-01-08 11:57 ` [PATCH 25/31] CAPI: Drop capiminor's unused inbytes counter Jan Kiszka
2010-01-08 12:43 ` [PATCH 26/31] CAPI: Fix locking around capiminor's output queue Jan Kiszka
2010-01-08 12:49 ` [PATCH 27/31] CAPI: Clean up capiminor_*_ack Jan Kiszka
2010-01-08 13:38 ` [PATCH 22/31] CAPI: Rework tty locking in RX and TX path of capiminor Jan Kiszka
2010-01-08 14:11 ` [PATCH 28/31] CAPI: Drop handle_minor_send return value Jan Kiszka
2010-01-10 10:24 ` [PATCH 09/31] CAPI: Rework controller state notifier Jan Kiszka
2010-01-10 13:07 ` [PATCH 29/31] CAPI: Drop special controller lookup from capi20_put_message Jan Kiszka
2010-01-10 13:12 ` [PATCH 30/31] CAPI: Remove experimental tag from middleware feature Jan Kiszka
2010-01-23 12:23 ` Alan Cox
2010-01-23 13:13 ` Jan Kiszka
2010-01-23 13:56 ` Alan Cox
2010-01-10 13:21 ` [PATCH 31/31] CAPI: Officially claim char major 191 Jan Kiszka
2010-01-23 12:24 ` Alan Cox
2010-01-23 12:48 ` Marcel Holtmann
2010-01-23 13:13 ` Jan Kiszka
2010-01-23 14:25 ` Marcel Holtmann
2010-01-23 13:32 ` Karsten Keil
2010-01-23 14:28 ` Marcel Holtmann
2010-01-23 14:49 ` Jan Kiszka
2010-01-23 9:18 ` [PATCH 00/31] CAPI: Major rework, tons of bug fixes David Miller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=c9ce6c91b2b475a59d338a4e97620d704ccf6fb6.1264201407.git.jan.kiszka@web.de \
--to=jan.kiszka@web.de \
--cc=davem@davemloft.net \
--cc=i4ldeveloper@listserv.isdn4linux.de \
--cc=isdn4linux@listserv.isdn4linux.de \
--cc=isdn@linux-pingi.de \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®