X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=drivers%2Fchar%2Fhvc_console.c;h=94e7e3c8c05ad3f0720aaae3d6df588eebd2d50b;hb=ae1b41715ee2aae356fbcca032838b71d70b855f;hp=44160d5ebca06dbcd7e300c9835cbeb1763c1a4c;hpb=bed9759b2e6bd938097389f6bd2ac8d622fa3884;p=safe%2Fjmp%2Flinux-2.6 diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c index 44160d5..94e7e3c 100644 --- a/drivers/char/hvc_console.c +++ b/drivers/char/hvc_console.c @@ -27,7 +27,6 @@ #include #include #include -#include #include #include #include @@ -75,23 +74,6 @@ static int hvc_init(void); static int sysrq_pressed; #endif -struct hvc_struct { - spinlock_t lock; - int index; - struct tty_struct *tty; - unsigned int count; - int do_wakeup; - char *outbuf; - int outbuf_size; - int n_outbuf; - uint32_t vtermno; - struct hv_ops *ops; - int irq_requested; - int irq; - struct list_head next; - struct kref kref; /* ref count & hvc_struct lifetime */ -}; - /* dynamic list of hvc_struct instances */ static LIST_HEAD(hvc_structs); @@ -179,7 +161,7 @@ static void hvc_console_print(struct console *co, const char *b, } } else { r = cons_ops[index]->put_chars(vtermnos[index], c, i); - if (r < 0) { + if (r <= 0) { /* throw away chars on error */ i = 0; } else if (r > 0) { @@ -298,27 +280,15 @@ int hvc_instantiate(uint32_t vtermno, int index, struct hv_ops *ops) return 0; } +EXPORT_SYMBOL_GPL(hvc_instantiate); /* Wake the sleeping khvcd */ -static void hvc_kick(void) +void hvc_kick(void) { hvc_kicked = 1; wake_up_process(hvc_task); } - -static int hvc_poll(struct hvc_struct *hp); - -/* - * NOTE: This API isn't used if the console adapter doesn't support interrupts. - * In this case the console is poll driven. - */ -static irqreturn_t hvc_handle_interrupt(int irq, void *dev_instance) -{ - /* if hvc_poll request a repoll, then kick the hvcd thread */ - if (hvc_poll(dev_instance)) - hvc_kick(); - return IRQ_HANDLED; -} +EXPORT_SYMBOL_GPL(hvc_kick); static void hvc_unthrottle(struct tty_struct *tty) { @@ -333,7 +303,6 @@ static int hvc_open(struct tty_struct *tty, struct file * filp) { struct hvc_struct *hp; unsigned long flags; - int irq = 0; int rc = 0; /* Auto increments kref reference if found. */ @@ -349,21 +318,16 @@ static int hvc_open(struct tty_struct *tty, struct file * filp) } /* else count == 0 */ tty->driver_data = hp; - tty->low_latency = 1; /* Makes flushes to ldisc synchronous. */ hp->tty = tty; - /* Save for request_irq outside of spin_lock. */ - irq = hp->irq; - if (irq) - hp->irq_requested = 1; spin_unlock_irqrestore(&hp->lock, flags); - /* check error, fallback to non-irq */ - if (irq) - rc = request_irq(irq, hvc_handle_interrupt, IRQF_DISABLED, "hvc_console", hp); + + if (hp->ops->notifier_add) + rc = hp->ops->notifier_add(hp, hp->data); /* - * If the request_irq() fails and we return an error. The tty layer + * If the notifier fails we return an error. The tty layer * will call hvc_close() after a failed open but we don't want to clean * up there so we'll clean up here and clear out the previously set * tty fields and return the kref reference. @@ -371,7 +335,6 @@ static int hvc_open(struct tty_struct *tty, struct file * filp) if (rc) { spin_lock_irqsave(&hp->lock, flags); hp->tty = NULL; - hp->irq_requested = 0; spin_unlock_irqrestore(&hp->lock, flags); tty->driver_data = NULL; kref_put(&hp->kref, destroy_hvc_struct); @@ -386,7 +349,6 @@ static int hvc_open(struct tty_struct *tty, struct file * filp) static void hvc_close(struct tty_struct *tty, struct file * filp) { struct hvc_struct *hp; - int irq = 0; unsigned long flags; if (tty_hung_up_p(filp)) @@ -404,24 +366,22 @@ static void hvc_close(struct tty_struct *tty, struct file * filp) spin_lock_irqsave(&hp->lock, flags); if (--hp->count == 0) { - if (hp->irq_requested) - irq = hp->irq; - hp->irq_requested = 0; - /* We are done with the tty pointer now. */ hp->tty = NULL; spin_unlock_irqrestore(&hp->lock, flags); + if (hp->ops->notifier_del) + hp->ops->notifier_del(hp, hp->data); + + /* cancel pending tty resize work */ + cancel_work_sync(&hp->tty_resize); + /* * Chain calls chars_in_buffer() and returns immediately if * there is no buffered data otherwise sleeps on a wait queue * waking periodically to check chars_in_buffer(). */ tty_wait_until_sent(tty, HVC_CLOSE_WAIT); - - if (irq) - free_irq(irq, hp); - } else { if (hp->count < 0) printk(KERN_ERR "hvc_close %X: oops, count is %d\n", @@ -436,12 +396,14 @@ static void hvc_hangup(struct tty_struct *tty) { struct hvc_struct *hp = tty->driver_data; unsigned long flags; - int irq = 0; int temp_open_count; if (!hp) return; + /* cancel pending tty resize work */ + cancel_work_sync(&hp->tty_resize); + spin_lock_irqsave(&hp->lock, flags); /* @@ -458,13 +420,12 @@ static void hvc_hangup(struct tty_struct *tty) hp->count = 0; hp->n_outbuf = 0; hp->tty = NULL; - if (hp->irq_requested) - /* Saved for use outside of spin_lock. */ - irq = hp->irq; - hp->irq_requested = 0; + spin_unlock_irqrestore(&hp->lock, flags); - if (irq) - free_irq(irq, hp); + + if (hp->ops->notifier_hangup) + hp->ops->notifier_hangup(hp, hp->data); + while(temp_open_count) { --temp_open_count; kref_put(&hp->kref, destroy_hvc_struct); @@ -475,7 +436,7 @@ static void hvc_hangup(struct tty_struct *tty) * Push buffered characters whether they were just recently buffered or waiting * on a blocked hypervisor. Call this function with hp->lock held. */ -static void hvc_push(struct hvc_struct *hp) +static int hvc_push(struct hvc_struct *hp) { int n; @@ -483,7 +444,7 @@ static void hvc_push(struct hvc_struct *hp) if (n <= 0) { if (n == 0) { hp->do_wakeup = 1; - return; + return 0; } /* throw away output on error; this happens when there is no session connected to the vterm. */ @@ -494,6 +455,8 @@ static void hvc_push(struct hvc_struct *hp) memmove(hp->outbuf, hp->outbuf + n, hp->n_outbuf); else hp->do_wakeup = 1; + + return n; } static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count) @@ -536,6 +499,39 @@ static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count return written; } +/** + * hvc_set_winsz() - Resize the hvc tty terminal window. + * @work: work structure. + * + * The routine shall not be called within an atomic context because it + * might sleep. + * + * Locking: hp->lock + */ +static void hvc_set_winsz(struct work_struct *work) +{ + struct hvc_struct *hp; + unsigned long hvc_flags; + struct tty_struct *tty; + struct winsize ws; + + hp = container_of(work, struct hvc_struct, tty_resize); + if (!hp) + return; + + spin_lock_irqsave(&hp->lock, hvc_flags); + if (!hp->tty) { + spin_unlock_irqrestore(&hp->lock, hvc_flags); + return; + } + ws = hp->ws; + tty = tty_kref_get(hp->tty); + spin_unlock_irqrestore(&hp->lock, hvc_flags); + + tty_do_resize(tty, &ws); + tty_kref_put(tty); +} + /* * This is actually a contract between the driver and the tty layer outlining * how much write room the driver can guarantee will be sent OR BUFFERED. This @@ -575,23 +571,27 @@ static u32 timeout = MIN_TIMEOUT; #define HVC_POLL_READ 0x00000001 #define HVC_POLL_WRITE 0x00000002 -static int hvc_poll(struct hvc_struct *hp) +int hvc_poll(struct hvc_struct *hp) { struct tty_struct *tty; int i, n, poll_mask = 0; char buf[N_INBUF] __ALIGNED__; unsigned long flags; int read_total = 0; + int written_total = 0; spin_lock_irqsave(&hp->lock, flags); /* Push pending writes */ if (hp->n_outbuf > 0) - hvc_push(hp); + written_total = hvc_push(hp); /* Reschedule us if still some write pending */ - if (hp->n_outbuf > 0) + if (hp->n_outbuf > 0) { poll_mask |= HVC_POLL_WRITE; + /* If hvc_push() was not able to write, sleep a few msecs */ + timeout = (written_total) ? 0 : MIN_TIMEOUT; + } /* No tty attached, just skip */ tty = hp->tty; @@ -602,10 +602,10 @@ static int hvc_poll(struct hvc_struct *hp) if (test_bit(TTY_THROTTLED, &tty->flags)) goto throttled; - /* If we aren't interrupt driven and aren't throttled, we always + /* If we aren't notifier driven and aren't throttled, we always * request a reschedule */ - if (hp->irq == 0) + if (!hp->irq_requested) poll_mask |= HVC_POLL_READ; /* Read data if any */ @@ -641,8 +641,11 @@ static int hvc_poll(struct hvc_struct *hp) /* Handle the SysRq Hack */ /* XXX should support a sequence */ if (buf[i] == '\x0f') { /* ^O */ - sysrq_pressed = 1; - continue; + /* if ^O is pressed again, reset + * sysrq_pressed and flip ^O char */ + sysrq_pressed = !sysrq_pressed; + if (sysrq_pressed) + continue; } else if (sysrq_pressed) { handle_sysrq(buf[i], tty); sysrq_pressed = 0; @@ -674,12 +677,24 @@ static int hvc_poll(struct hvc_struct *hp) return poll_mask; } +EXPORT_SYMBOL_GPL(hvc_poll); -#if defined(CONFIG_XMON) && defined(CONFIG_SMP) -extern cpumask_t cpus_in_xmon; -#else -static const cpumask_t cpus_in_xmon = CPU_MASK_NONE; -#endif +/** + * hvc_resize() - Update terminal window size information. + * @hp: HVC console pointer + * @ws: Terminal window size structure + * + * Stores the specified window size information in the hvc structure of @hp. + * The function schedule the tty resize update. + * + * Locking: Locking free; the function MUST be called holding hp->lock + */ +void hvc_resize(struct hvc_struct *hp, struct winsize ws) +{ + hp->ws = ws; + schedule_work(&hp->tty_resize); +} +EXPORT_SYMBOL_GPL(hvc_resize); /* * This kthread is either polling or interrupt driven. This is determined by @@ -698,7 +713,7 @@ static int khvcd(void *unused) hvc_kicked = 0; try_to_freeze(); wmb(); - if (cpus_empty(cpus_in_xmon)) { + if (!cpus_are_in_xmon()) { spin_lock(&hvc_structs_lock); list_for_each_entry(hp, &hvc_structs, next) { poll_mask |= hvc_poll(hp); @@ -708,10 +723,6 @@ static int khvcd(void *unused) poll_mask |= HVC_POLL_READ; if (hvc_kicked) continue; - if (poll_mask & HVC_POLL_WRITE) { - yield(); - continue; - } set_current_state(TASK_INTERRUPTIBLE); if (!hvc_kicked) { if (poll_mask == 0) @@ -739,7 +750,7 @@ static const struct tty_operations hvc_ops = { .chars_in_buffer = hvc_chars_in_buffer, }; -struct hvc_struct __devinit *hvc_alloc(uint32_t vtermno, int irq, +struct hvc_struct __devinit *hvc_alloc(uint32_t vtermno, int data, struct hv_ops *ops, int outbuf_size) { struct hvc_struct *hp; @@ -752,21 +763,20 @@ struct hvc_struct __devinit *hvc_alloc(uint32_t vtermno, int irq, return ERR_PTR(err); } - hp = kmalloc(ALIGN(sizeof(*hp), sizeof(long)) + outbuf_size, + hp = kzalloc(ALIGN(sizeof(*hp), sizeof(long)) + outbuf_size, GFP_KERNEL); if (!hp) return ERR_PTR(-ENOMEM); - memset(hp, 0x00, sizeof(*hp)); - hp->vtermno = vtermno; - hp->irq = irq; + hp->data = data; hp->ops = ops; hp->outbuf_size = outbuf_size; hp->outbuf = &((char *)hp)[ALIGN(sizeof(*hp), sizeof(long))]; kref_init(&hp->kref); + INIT_WORK(&hp->tty_resize, hvc_set_winsz); spin_lock_init(&hp->lock); spin_lock(&hvc_structs_lock); @@ -790,8 +800,9 @@ struct hvc_struct __devinit *hvc_alloc(uint32_t vtermno, int irq, return hp; } +EXPORT_SYMBOL_GPL(hvc_alloc); -int __devexit hvc_remove(struct hvc_struct *hp) +int hvc_remove(struct hvc_struct *hp) { unsigned long flags; struct tty_struct *tty; @@ -844,7 +855,7 @@ static int hvc_init(void) drv->minor_start = HVC_MINOR; drv->type = TTY_DRIVER_TYPE_SYSTEM; drv->init_termios = tty_std_termios; - drv->flags = TTY_DRIVER_REAL_RAW; + drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS; tty_set_operations(drv, &hvc_ops); /* Always start the kthread because there can be hotplug vty adapters @@ -862,16 +873,19 @@ static int hvc_init(void) goto stop_thread; } - /* FIXME: This mb() seems completely random. Remove it. */ - mb(); + /* + * Make sure tty is fully registered before allowing it to be + * found by hvc_console_device. + */ + smp_mb(); hvc_driver = drv; return 0; -put_tty: - put_tty_driver(hvc_driver); stop_thread: kthread_stop(hvc_task); hvc_task = NULL; +put_tty: + put_tty_driver(drv); out: return err; }