X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=drivers%2Fchar%2Fhvc_console.c;h=94e7e3c8c05ad3f0720aaae3d6df588eebd2d50b;hb=413d63d7106b914a4a004ac08698f10c618e4616;hp=d59c642f9654c5a189ce62634f1368c859e2702c;hpb=d5ee257c3342185ba8ab642d125d192eb99ea8f2;p=safe%2Fjmp%2Flinux-2.6 diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c index d59c642..94e7e3c 100644 --- a/drivers/char/hvc_console.c +++ b/drivers/char/hvc_console.c @@ -22,13 +22,11 @@ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ -#include #include #include #include #include #include -#include #include #include #include @@ -39,15 +37,15 @@ #include #include #include +#include + #include -#include -#include + +#include "hvc_console.h" #define HVC_MAJOR 229 #define HVC_MINOR 0 -#define TIMEOUT (10) - /* * Wait this long per iteration while trying to push buffered data to the * hypervisor before allowing the tty to complete a close operation. @@ -55,17 +53,14 @@ #define HVC_CLOSE_WAIT (HZ/100) /* 1/10 of a second */ /* - * The Linux TTY code does not support dynamic addition of tty derived devices - * so we need to know how many tty devices we might need when space is allocated - * for the tty device. Since this driver supports hotplug of vty adapters we - * need to make sure we have enough allocated. + * These sizes are most efficient for vio, because they are the + * native transfer size. We could make them selectable in the + * future to better deal with backends that want other buffer sizes. */ -#define HVC_ALLOC_TTY_ADAPTERS 8 - #define N_OUTBUF 16 #define N_INBUF 16 -#define __ALIGNED__ __attribute__((__aligned__(8))) +#define __ALIGNED__ __attribute__((__aligned__(sizeof(long)))) static struct tty_driver *hvc_driver; static struct task_struct *hvc_task; @@ -73,28 +68,14 @@ static struct task_struct *hvc_task; /* Picks up late kicks after list walk but before schedule() */ static int hvc_kicked; +static int hvc_init(void); + #ifdef CONFIG_MAGIC_SYSRQ 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[N_OUTBUF] __ALIGNED__; - int n_outbuf; - uint32_t vtermno; - int irq_requested; - int irq; - struct list_head next; - struct kobject kobj; /* ref count & hvc_struct lifetime */ - struct vio_dev *vdev; -}; - /* dynamic list of hvc_struct instances */ -static struct list_head hvc_structs = LIST_HEAD_INIT(hvc_structs); +static LIST_HEAD(hvc_structs); /* * Protect the list of hvc_struct instances from inserts and removals during @@ -105,16 +86,16 @@ static DEFINE_SPINLOCK(hvc_structs_lock); /* * This value is used to assign a tty->index value to a hvc_struct based * upon order of exposure via hvc_probe(), when we can not match it to - * a console canidate registered with hvc_instantiate(). + * a console candidate registered with hvc_instantiate(). */ static int last_hvc = -1; /* - * Do not call this function with either the hvc_strucst_lock or the hvc_struct - * lock held. If successful, this function increments the kobject reference + * Do not call this function with either the hvc_structs_lock or the hvc_struct + * lock held. If successful, this function increments the kref reference * count against the target hvc_struct so it should be released when finished. */ -struct hvc_struct *hvc_get_by_index(int index) +static struct hvc_struct *hvc_get_by_index(int index) { struct hvc_struct *hp; unsigned long flags; @@ -124,7 +105,7 @@ struct hvc_struct *hvc_get_by_index(int index) list_for_each_entry(hp, &hvc_structs, next) { spin_lock_irqsave(&hp->lock, flags); if (hp->index == index) { - kobject_get(&hp->kobj); + kref_get(&hp->kref); spin_unlock_irqrestore(&hp->lock, flags); spin_unlock(&hvc_structs_lock); return hp; @@ -144,6 +125,7 @@ struct hvc_struct *hvc_get_by_index(int index) * console interfaces but can still be used as a tty device. This has to be * static because kmalloc will not work during early console init. */ +static struct hv_ops *cons_ops[MAX_NR_HVC_CONSOLES]; static uint32_t vtermnos[MAX_NR_HVC_CONSOLES] = {[0 ... MAX_NR_HVC_CONSOLES - 1] = -1}; @@ -152,18 +134,19 @@ static uint32_t vtermnos[MAX_NR_HVC_CONSOLES] = * hvc_console_setup() finds adapters. */ -void hvc_console_print(struct console *co, const char *b, unsigned count) +static void hvc_console_print(struct console *co, const char *b, + unsigned count) { - char c[16] __ALIGNED__; + char c[N_OUTBUF] __ALIGNED__; unsigned i = 0, n = 0; - int r, donecr = 0; + int r, donecr = 0, index = co->index; /* Console access attempt outside of acceptable console range. */ - if (co->index >= MAX_NR_HVC_CONSOLES) + if (index >= MAX_NR_HVC_CONSOLES) return; - /* This console adapter was removed so it is not useable. */ - if (vtermnos[co->index] < 0) + /* This console adapter was removed so it is not usable. */ + if (vtermnos[index] < 0) return; while (count > 0 || i > 0) { @@ -177,8 +160,8 @@ void hvc_console_print(struct console *co, const char *b, unsigned count) --count; } } else { - r = hvc_put_chars(vtermnos[co->index], c, i); - if (r < 0) { + r = cons_ops[index]->put_chars(vtermnos[index], c, i); + if (r <= 0) { /* throw away chars on error */ i = 0; } else if (r > 0) { @@ -210,7 +193,7 @@ static int __init hvc_console_setup(struct console *co, char *options) return 0; } -struct console hvc_con_driver = { +static struct console hvc_con_driver = { .name = "hvc", .write = hvc_console_print, .device = hvc_console_device, @@ -220,7 +203,7 @@ struct console hvc_con_driver = { }; /* - * Early console initialization. Preceeds driver initialization. + * Early console initialization. Precedes driver initialization. * * (1) we are first, and the user specified another driver * -- index will remain -1 @@ -241,13 +224,30 @@ static int __init hvc_console_init(void) } console_initcall(hvc_console_init); +/* callback when the kboject ref count reaches zero. */ +static void destroy_hvc_struct(struct kref *kref) +{ + struct hvc_struct *hp = container_of(kref, struct hvc_struct, kref); + unsigned long flags; + + spin_lock(&hvc_structs_lock); + + spin_lock_irqsave(&hp->lock, flags); + list_del(&(hp->next)); + spin_unlock_irqrestore(&hp->lock, flags); + + spin_unlock(&hvc_structs_lock); + + kfree(hp); +} + /* * hvc_instantiate() is an early console discovery method which locates * consoles * prior to the vio subsystem discovering them. Hotplugged * vty adapters do NOT get an hvc_instantiate() callback since they * appear after early console init. */ -int hvc_instantiate(uint32_t vtermno, int index) +int hvc_instantiate(uint32_t vtermno, int index, struct hv_ops *ops) { struct hvc_struct *hp; @@ -257,16 +257,17 @@ int hvc_instantiate(uint32_t vtermno, int index) if (vtermnos[index] != -1) return -1; - /* make sure no no tty has been registerd in this index */ + /* make sure no no tty has been registered in this index */ hp = hvc_get_by_index(index); if (hp) { - kobject_put(&hp->kobj); + kref_put(&hp->kref, destroy_hvc_struct); return -1; } vtermnos[index] = vtermno; + cons_ops[index] = ops; - /* reserve all indices upto and including this index */ + /* reserve all indices up to and including this index */ if (last_hvc < index) last_hvc = index; @@ -279,27 +280,15 @@ int hvc_instantiate(uint32_t vtermno, int index) 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, struct pt_regs *regs) -{ - /* 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) { @@ -314,15 +303,11 @@ static int hvc_open(struct tty_struct *tty, struct file * filp) { struct hvc_struct *hp; unsigned long flags; - int irq = NO_IRQ; int rc = 0; - struct kobject *kobjp; - /* Auto increments kobject reference if found. */ - if (!(hp = hvc_get_by_index(tty->index))) { - printk(KERN_WARNING "hvc_console: tty open failed, no vty associated with tty.\n"); + /* Auto increments kref reference if found. */ + if (!(hp = hvc_get_by_index(tty->index))) return -ENODEV; - } spin_lock_irqsave(&hp->lock, flags); /* Check and then increment for fast path open. */ @@ -333,32 +318,26 @@ static int hvc_open(struct tty_struct *tty, struct file * filp) } /* else count == 0 */ tty->driver_data = hp; - hp->tty = tty; - /* Save for request_irq outside of spin_lock. */ - irq = hp->irq; - if (irq != NO_IRQ) - hp->irq_requested = 1; - kobjp = &hp->kobj; + hp->tty = tty; spin_unlock_irqrestore(&hp->lock, flags); - /* check error, fallback to non-irq */ - if (irq != NO_IRQ) - rc = request_irq(irq, hvc_handle_interrupt, SA_INTERRUPT, "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 kobject reference. + * tty fields and return the kref reference. */ 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; - kobject_put(kobjp); + kref_put(&hp->kref, destroy_hvc_struct); printk(KERN_ERR "hvc_open: request_irq failed with rc %d.\n", rc); } /* Force wakeup of the polling thread */ @@ -370,8 +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; - struct kobject *kobjp; - int irq = NO_IRQ; unsigned long flags; if (tty_hung_up_p(filp)) @@ -380,7 +357,7 @@ static void hvc_close(struct tty_struct *tty, struct file * filp) /* * No driver_data means that this close was issued after a failed * hvc_open by the tty layer's release_dev() function and we can just - * exit cleanly because the kobject reference wasn't made. + * exit cleanly because the kref reference wasn't made. */ if (!tty->driver_data) return; @@ -388,26 +365,23 @@ static void hvc_close(struct tty_struct *tty, struct file * filp) hp = tty->driver_data; spin_lock_irqsave(&hp->lock, flags); - kobjp = &hp->kobj; 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 != NO_IRQ) - free_irq(irq, hp); - } else { if (hp->count < 0) printk(KERN_ERR "hvc_close %X: oops, count is %d\n", @@ -415,20 +389,21 @@ static void hvc_close(struct tty_struct *tty, struct file * filp) spin_unlock_irqrestore(&hp->lock, flags); } - kobject_put(kobjp); + kref_put(&hp->kref, destroy_hvc_struct); } static void hvc_hangup(struct tty_struct *tty) { struct hvc_struct *hp = tty->driver_data; unsigned long flags; - int irq = NO_IRQ; int temp_open_count; - struct kobject *kobjp; if (!hp) return; + /* cancel pending tty resize work */ + cancel_work_sync(&hp->tty_resize); + spin_lock_irqsave(&hp->lock, flags); /* @@ -441,21 +416,19 @@ static void hvc_hangup(struct tty_struct *tty) return; } - kobjp = &hp->kobj; temp_open_count = hp->count; 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 != NO_IRQ) - free_irq(irq, hp); + + if (hp->ops->notifier_hangup) + hp->ops->notifier_hangup(hp, hp->data); + while(temp_open_count) { --temp_open_count; - kobject_put(kobjp); + kref_put(&hp->kref, destroy_hvc_struct); } } @@ -463,14 +436,16 @@ 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; - n = hvc_put_chars(hp->vtermno, hp->outbuf, hp->n_outbuf); + n = hp->ops->put_chars(hp->vtermno, hp->outbuf, hp->n_outbuf); if (n <= 0) { - if (n == 0) - return; + if (n == 0) { + hp->do_wakeup = 1; + return 0; + } /* throw away output on error; this happens when there is no session connected to the vterm. */ hp->n_outbuf = 0; @@ -480,21 +455,30 @@ 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 inline int __hvc_write_kernel(struct hvc_struct *hp, - const unsigned char *buf, int count) +static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count) { + struct hvc_struct *hp = tty->driver_data; unsigned long flags; int rsize, written = 0; + /* This write was probably executed during a tty close. */ + if (!hp) + return -EPIPE; + + if (hp->count <= 0) + return -EIO; + spin_lock_irqsave(&hp->lock, flags); /* Push pending writes */ if (hp->n_outbuf > 0) hvc_push(hp); - while (count > 0 && (rsize = N_OUTBUF - hp->n_outbuf) > 0) { + while (count > 0 && (rsize = hp->outbuf_size - hp->n_outbuf) > 0) { if (rsize > count) rsize = count; memcpy(hp->outbuf + hp->n_outbuf, buf, rsize); @@ -506,26 +490,8 @@ static inline int __hvc_write_kernel(struct hvc_struct *hp, } spin_unlock_irqrestore(&hp->lock, flags); - return written; -} -static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count) -{ - struct hvc_struct *hp = tty->driver_data; - int written; - - /* This write was probably executed during a tty close. */ - if (!hp) - return -EPIPE; - - if (hp->count <= 0) - return -EIO; - - written = __hvc_write_kernel(hp, buf, count); - /* * Racy, but harmless, kick thread if there is still pending data. - * There really is nothing wrong with kicking the thread, even if there - * is no buffered data. */ if (hp->n_outbuf) hvc_kick(); @@ -533,9 +499,42 @@ 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 guarentee will be sent OR BUFFERED. This + * how much write room the driver can guarantee will be sent OR BUFFERED. This * driver MUST honor the return value. */ static int hvc_write_room(struct tty_struct *tty) @@ -545,7 +544,7 @@ static int hvc_write_room(struct tty_struct *tty) if (!hp) return -1; - return N_OUTBUF - hp->n_outbuf; + return hp->outbuf_size - hp->n_outbuf; } static int hvc_chars_in_buffer(struct tty_struct *tty) @@ -557,26 +556,42 @@ static int hvc_chars_in_buffer(struct tty_struct *tty) return hp->n_outbuf; } +/* + * timeout will vary between the MIN and MAX values defined here. By default + * and during console activity we will use a default MIN_TIMEOUT of 10. When + * the console is idle, we increase the timeout value on each pass through + * msleep until we reach the max. This may be noticeable as a brief (average + * one second) delay on the console before the console responds to input when + * there has been no input for some time. + */ +#define MIN_TIMEOUT (10) +#define MAX_TIMEOUT (2000) +static u32 timeout = MIN_TIMEOUT; + #define HVC_POLL_READ 0x00000001 #define HVC_POLL_WRITE 0x00000002 -#define HVC_POLL_QUICK 0x00000004 -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; @@ -587,17 +602,15 @@ 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 == NO_IRQ) + if (!hp->irq_requested) poll_mask |= HVC_POLL_READ; /* Read data if any */ for (;;) { - int count = N_INBUF; - if (count > (TTY_FLIPBUF_SIZE - tty->flip.count)) - count = TTY_FLIPBUF_SIZE - tty->flip.count; + int count = tty_buffer_request_room(tty, N_INBUF); /* If flip is full, just reschedule a later read */ if (count == 0) { @@ -605,13 +618,20 @@ static int hvc_poll(struct hvc_struct *hp) break; } - n = hvc_get_chars(hp->vtermno, buf, count); + n = hp->ops->get_chars(hp->vtermno, buf, count); if (n <= 0) { /* Hangup the tty when disconnected from host */ if (n == -EPIPE) { spin_unlock_irqrestore(&hp->lock, flags); tty_hangup(tty); spin_lock_irqsave(&hp->lock, flags); + } else if ( n == -EAGAIN ) { + /* + * Some back-ends can only ensure a certain min + * num of bytes read, which may be > 'count'. + * Let the tty clear the flip buff to make room. + */ + poll_mask |= HVC_POLL_READ; } break; } @@ -621,10 +641,13 @@ 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], NULL, tty); + handle_sysrq(buf[i], tty); sysrq_pressed = 0; continue; } @@ -633,19 +656,7 @@ static int hvc_poll(struct hvc_struct *hp) tty_insert_flip_char(tty, buf[i], 0); } - if (tty->flip.count) - tty_schedule_flip(tty); - - /* - * Account for the total amount read in one loop, and if above - * 64 bytes, we do a quick schedule loop to let the tty grok - * the data and eventually throttle us. - */ read_total += n; - if (read_total >= 64) { - poll_mask |= HVC_POLL_QUICK; - break; - } } throttled: /* Wakeup write queue if necessary */ @@ -656,31 +667,53 @@ static int hvc_poll(struct hvc_struct *hp) bail: spin_unlock_irqrestore(&hp->lock, flags); + if (read_total) { + /* Activity is occurring, so reset the polling backoff value to + a minimum for performance. */ + timeout = MIN_TIMEOUT; + + tty_flip_buffer_push(tty); + } + 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 * calling hvc_poll() who determines whether a console adapter support * interrupts. */ -int khvcd(void *unused) +static int khvcd(void *unused) { int poll_mask; struct hvc_struct *hp; + set_freezable(); __set_current_state(TASK_RUNNING); do { poll_mask = 0; 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); @@ -690,16 +723,16 @@ int khvcd(void *unused) poll_mask |= HVC_POLL_READ; if (hvc_kicked) continue; - if (poll_mask & HVC_POLL_QUICK) { - yield(); - continue; - } set_current_state(TASK_INTERRUPTIBLE); if (!hvc_kicked) { if (poll_mask == 0) schedule(); - else - msleep_interruptible(TIMEOUT); + else { + if (timeout < MAX_TIMEOUT) + timeout += (timeout >> 6) + 1; + + msleep_interruptible(timeout); + } } __set_current_state(TASK_RUNNING); } while (!kthread_should_stop()); @@ -707,7 +740,7 @@ int khvcd(void *unused) return 0; } -static struct tty_operations hvc_ops = { +static const struct tty_operations hvc_ops = { .open = hvc_open, .close = hvc_close, .write = hvc_write, @@ -717,51 +750,33 @@ static struct tty_operations hvc_ops = { .chars_in_buffer = hvc_chars_in_buffer, }; -/* callback when the kboject ref count reaches zero. */ -static void destroy_hvc_struct(struct kobject *kobj) -{ - struct hvc_struct *hp = container_of(kobj, struct hvc_struct, kobj); - unsigned long flags; - - spin_lock(&hvc_structs_lock); - - spin_lock_irqsave(&hp->lock, flags); - list_del(&(hp->next)); - spin_unlock_irqrestore(&hp->lock, flags); - - spin_unlock(&hvc_structs_lock); - - kfree(hp); -} - -static struct kobj_type hvc_kobj_type = { - .release = destroy_hvc_struct, -}; - -static int __devinit hvc_probe( - struct vio_dev *dev, - const struct vio_device_id *id) +struct hvc_struct __devinit *hvc_alloc(uint32_t vtermno, int data, + struct hv_ops *ops, int outbuf_size) { struct hvc_struct *hp; int i; - /* probed with invalid parameters. */ - if (!dev || !id) - return -EPERM; + /* We wait until a driver actually comes along */ + if (!hvc_driver) { + int err = hvc_init(); + if (err) + return ERR_PTR(err); + } - hp = kmalloc(sizeof(*hp), GFP_KERNEL); + hp = kzalloc(ALIGN(sizeof(*hp), sizeof(long)) + outbuf_size, + GFP_KERNEL); if (!hp) - return -ENOMEM; + return ERR_PTR(-ENOMEM); - memset(hp, 0x00, sizeof(*hp)); - hp->vtermno = dev->unit_address; - hp->vdev = dev; - hp->vdev->dev.driver_data = hp; - hp->irq = dev->irq; + hp->vtermno = vtermno; + hp->data = data; + hp->ops = ops; + hp->outbuf_size = outbuf_size; + hp->outbuf = &((char *)hp)[ALIGN(sizeof(*hp), sizeof(long))]; - kobject_init(&hp->kobj); - hp->kobj.ktype = &hvc_kobj_type; + kref_init(&hp->kref); + INIT_WORK(&hp->tty_resize, hvc_set_winsz); spin_lock_init(&hp->lock); spin_lock(&hvc_structs_lock); @@ -770,7 +785,8 @@ static int __devinit hvc_probe( * see if this vterm id matches one registered for console. */ for (i=0; i < MAX_NR_HVC_CONSOLES; i++) - if (vtermnos[i] == hp->vtermno) + if (vtermnos[i] == hp->vtermno && + cons_ops[i] == hp->ops) break; /* no matching slot, just use a counter */ @@ -782,19 +798,17 @@ static int __devinit hvc_probe( list_add_tail(&(hp->next), &hvc_structs); spin_unlock(&hvc_structs_lock); - return 0; + return hp; } +EXPORT_SYMBOL_GPL(hvc_alloc); -static int __devexit hvc_remove(struct vio_dev *dev) +int hvc_remove(struct hvc_struct *hp) { - struct hvc_struct *hp = dev->dev.driver_data; unsigned long flags; - struct kobject *kobjp; struct tty_struct *tty; spin_lock_irqsave(&hp->lock, flags); tty = hp->tty; - kobjp = &hp->kobj; if (hp->index < MAX_NR_HVC_CONSOLES) vtermnos[hp->index] = -1; @@ -804,12 +818,12 @@ static int __devexit hvc_remove(struct vio_dev *dev) spin_unlock_irqrestore(&hp->lock, flags); /* - * We 'put' the instance that was grabbed when the kobject instance - * was intialized using kobject_init(). Let the last holder of this - * kobject cause it to be removed, which will probably be the tty_hangup + * We 'put' the instance that was grabbed when the kref instance + * was initialized using kref_init(). Let the last holder of this + * kref cause it to be removed, which will probably be the tty_hangup * below. */ - kobject_put(kobjp); + kref_put(&hp->kref, destroy_hvc_struct); /* * This function call will auto chain call hvc_hangup. The tty should @@ -821,73 +835,73 @@ static int __devexit hvc_remove(struct vio_dev *dev) return 0; } -char hvc_driver_name[] = "hvc_console"; - -static struct vio_device_id hvc_driver_table[] __devinitdata= { - {"serial", "hvterm1"}, - { NULL, } -}; -MODULE_DEVICE_TABLE(vio, hvc_driver_table); - -static struct vio_driver hvc_vio_driver = { - .name = hvc_driver_name, - .id_table = hvc_driver_table, - .probe = hvc_probe, - .remove = hvc_remove, -}; - -/* Driver initialization. Follow console initialization. This is where the TTY - * interfaces start to become available. */ -int __init hvc_init(void) +/* Driver initialization: called as soon as someone uses hvc_alloc(). */ +static int hvc_init(void) { - int rc; + struct tty_driver *drv; + int err; /* We need more than hvc_count adapters due to hotplug additions. */ - hvc_driver = alloc_tty_driver(HVC_ALLOC_TTY_ADAPTERS); - if (!hvc_driver) - return -ENOMEM; - - hvc_driver->owner = THIS_MODULE; - hvc_driver->devfs_name = "hvc/"; - hvc_driver->driver_name = "hvc"; - hvc_driver->name = "hvc"; - hvc_driver->major = HVC_MAJOR; - hvc_driver->minor_start = HVC_MINOR; - hvc_driver->type = TTY_DRIVER_TYPE_SYSTEM; - hvc_driver->init_termios = tty_std_termios; - hvc_driver->flags = TTY_DRIVER_REAL_RAW; - tty_set_operations(hvc_driver, &hvc_ops); - - if (tty_register_driver(hvc_driver)) - panic("Couldn't register hvc console driver\n"); + drv = alloc_tty_driver(HVC_ALLOC_TTY_ADAPTERS); + if (!drv) { + err = -ENOMEM; + goto out; + } + + drv->owner = THIS_MODULE; + drv->driver_name = "hvc"; + drv->name = "hvc"; + drv->major = HVC_MAJOR; + drv->minor_start = HVC_MINOR; + drv->type = TTY_DRIVER_TYPE_SYSTEM; + drv->init_termios = tty_std_termios; + 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 * added later. */ hvc_task = kthread_run(khvcd, NULL, "khvcd"); if (IS_ERR(hvc_task)) { - panic("Couldn't create kthread for console.\n"); - put_tty_driver(hvc_driver); - return -EIO; + printk(KERN_ERR "Couldn't create kthread for console.\n"); + err = PTR_ERR(hvc_task); + goto put_tty; + } + + err = tty_register_driver(drv); + if (err) { + printk(KERN_ERR "Couldn't register hvc console driver\n"); + goto stop_thread; } - /* Register as a vio device to receive callbacks */ - rc = vio_register_driver(&hvc_vio_driver); + /* + * Make sure tty is fully registered before allowing it to be + * found by hvc_console_device. + */ + smp_mb(); + hvc_driver = drv; + return 0; - return rc; +stop_thread: + kthread_stop(hvc_task); + hvc_task = NULL; +put_tty: + put_tty_driver(drv); +out: + return err; } -module_init(hvc_init); -/* This isn't particularily necessary due to this being a console driver +/* This isn't particularly necessary due to this being a console driver * but it is nice to be thorough. */ static void __exit hvc_exit(void) { - kthread_stop(hvc_task); + if (hvc_driver) { + kthread_stop(hvc_task); - vio_unregister_driver(&hvc_vio_driver); - tty_unregister_driver(hvc_driver); - /* return tty_struct instances allocated in hvc_init(). */ - put_tty_driver(hvc_driver); - unregister_console(&hvc_con_driver); + tty_unregister_driver(hvc_driver); + /* return tty_struct instances allocated in hvc_init(). */ + put_tty_driver(hvc_driver); + unregister_console(&hvc_con_driver); + } } module_exit(hvc_exit);