X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fchar%2Fhvcs.c;h=15b1d8cbc77d0b308a9f517a55011ef4f5fea1b2;hb=c7b5ebbddf7bcd3651947760f423e3783bbe6573;hp=96ca634caaa78d0e720116d6751bf5c3c3e4cfee;hpb=a2c21200f1c81b08cb55e417b68150bba439b646;p=linux-2.6.git diff --git a/drivers/char/hvcs.c b/drivers/char/hvcs.c index 96ca634ca..15b1d8cbc 100644 --- a/drivers/char/hvcs.c +++ b/drivers/char/hvcs.c @@ -88,37 +88,59 @@ #include /* - * 1.0.0 -> 1.1.0 Added kernel_thread scheduling methodology to driver to - * replace wait_task constructs. + * 1.3.0 -> 1.3.1 In hvcs_open memset(..,0x00,..) instead of memset(..,0x3F,00). + * Removed braces around single statements following conditionals. Removed '= + * 0' after static int declarations since these default to zero. Removed + * list_for_each_safe() and replaced with list_for_each_entry() in + * hvcs_get_by_index(). The 'safe' version is un-needed now that the driver is + * using spinlocks. Changed spin_lock_irqsave() to spin_lock() when locking + * hvcs_structs_lock and hvcs_pi_lock since these are not touched in an int + * handler. Initialized hvcs_structs_lock and hvcs_pi_lock to + * SPIN_LOCK_UNLOCKED at declaration time rather than in hvcs_module_init(). + * Added spin_lock around list_del() in destroy_hvcs_struct() to protect the + * list traversals from a deletion. Removed '= NULL' from pointer declaration + * statements since they are initialized NULL by default. Removed wmb() + * instances from hvcs_try_write(). They probably aren't needed with locking in + * place. Added check and cleanup for hvcs_pi_buff = kmalloc() in + * hvcs_module_init(). Exposed hvcs_struct.index via a sysfs attribute so that + * the coupling between /dev/hvcs* and a vty-server can be automatically + * determined. Moved kobject_put() in hvcs_open outside of the + * spin_unlock_irqrestore(). * - * 1.1.0 -> 1.2.0 Moved pi_buff initialization out of arch code into driver code - * and added locking to share this buffer between hvcs_struct instances. This - * is because the page_size kmalloc can't be done with a spin_lock held. + * 1.3.1 -> 1.3.2 Changed method for determining hvcs_struct->index and had it + * align with how the tty layer always assigns the lowest index available. This + * change resulted in a list of ints that denotes which indexes are available. + * Device additions and removals use the new hvcs_get_index() and + * hvcs_return_index() helper functions. The list is created with + * hvsc_alloc_index_list() and it is destroyed with hvcs_free_index_list(). + * Without these fixes hotplug vty-server adapter support goes crazy with this + * driver if the user removes a vty-server adapter. Moved free_irq() outside of + * the hvcs_final_close() function in order to get it out of the spinlock. + * Rearranged hvcs_close(). Cleaned up some printks and did some housekeeping + * on the changelog. Removed local CLC_LENGTH and used HVCS_CLC_LENGTH from + * arch/ppc64/hvcserver.h. * - * Also added sysfs attribute to manually disconnect the vty-server from the vty - * due to stupid firmware behavior when opening the connection then sending data - * then then quickly closing the connection would cause data loss on the - * receiving side. This required some reordering of the termination code. - * - * Fixed the hangup scenario and fixed memory leaks on module_exit. - * - * 1.2.0 -> 1.3.0 Moved from manual kernel thread creation & execution to - * kthread construct which replaced in-kernel IPC for thread termination with - * kthread_stop and kthread_should_stop. Explicit wait_queue handling was - * removed because kthread handles this. Minor bug fix to postpone partner_info - * clearing on hvcs_close until adapter removal to preserve context data for - * printk on partner connection free. Added lock to protect hvcs_structs so - * that hvcs_struct instances aren't added or removed during list traversal. - * Cleaned up comment style, added spaces after commas, and broke function - * declaration lines to be under 80 columns. + * 1.3.2 -> 1.3.3 Replaced yield() in hvcs_close() with tty_wait_until_sent() to + * prevent possible lockup with realtime scheduling as similarily pointed out by + * akpm in hvc_console. Changed resulted in the removal of hvcs_final_close() + * to reorder cleanup operations and prevent discarding of pending data during + * an hvcs_close(). Removed spinlock protection of hvcs_struct data members in + * hvcs_write_room() and hvcs_chars_in_buffer() because they aren't needed. */ -#define HVCS_DRIVER_VERSION "1.3.0" + +#define HVCS_DRIVER_VERSION "1.3.3" MODULE_AUTHOR("Ryan S. Arnold "); MODULE_DESCRIPTION("IBM hvcs (Hypervisor Virtual Console Server) Driver"); MODULE_LICENSE("GPL"); MODULE_VERSION(HVCS_DRIVER_VERSION); +/* + * Wait this long per iteration while trying to push buffered data to the + * hypervisor before allowing the tty to complete a close operation. + */ +#define HVCS_CLOSE_WAIT (HZ/100) /* 1/10 of a second */ + /* * Since the Linux TTY code does not currently (2-04-2004) support dynamic * addition of tty derived devices and we shouldn't allocate thousands of @@ -138,9 +160,9 @@ MODULE_VERSION(HVCS_DRIVER_VERSION); /* * We let Linux assign us a major number and we start the minors at zero. There - * is no intuitive mapping between minor number and the target partition. The - * mapping of minor number is related to the order the vty-servers are exposed - * to this driver via the hvcs_probe function. + * is no intuitive mapping between minor number and the target vty-server + * adapter except that each new vty-server adapter is always assigned to the + * smallest minor number available. */ #define HVCS_MINOR_START 0 @@ -152,9 +174,6 @@ MODULE_VERSION(HVCS_DRIVER_VERSION); */ #define __ALIGNED__ __attribute__((__aligned__(8))) -/* Converged location code string length + 1 null terminator */ -#define CLC_LENGTH 80 - /* * How much data can firmware send with each hvc_put_chars()? Maybe this * should be moved into an architecture specific area. @@ -194,27 +213,41 @@ char hvcs_driver_string[] = "IBM hvcs (Hypervisor Virtual Console Server) Driver"; /* Status of partner info rescan triggered via sysfs. */ -static int hvcs_rescan_status = 0; +static int hvcs_rescan_status; static struct tty_driver *hvcs_tty_driver; /* - * This is used to associate a vty-server, as it is exposed to this driver, with - * a preallocated tty_struct.index. The dev node and hvcs index numbers are not - * re-used after device removal otherwise removing and adding a new one would - * link a /dev/hvcs* entry to a different vty-server than it did before the - * removal. Incidentally, a newly exposed vty-server will always map to an - * incrementally higher /dev/hvcs* entry than the last exposed vty-server. + * In order to be somewhat sane this driver always associates the hvcs_struct + * index element with the numerically equal tty->index. This means that a + * hotplugged vty-server adapter will always map to the lowest index valued + * device node. If vty-servers were hotplug removed from the system and then + * new ones added the new vty-server may have the largest slot number of all + * the vty-server adapters in the partition but it may have the lowest dev node + * index of all the adapters due to the hole left by the hotplug removed + * adapter. There are a set of functions provided to get the lowest index for + * a new device as well as return the index to the list. This list is allocated + * with a number of elements equal to the number of device nodes requested when + * the module was inserted. + */ +static int *hvcs_index_list; + +/* + * How large is the list? This is kept for traversal since the list is + * dynamically created. */ -static int hvcs_struct_count = -1; +static int hvcs_index_count; /* * Used by the khvcsd to pick up I/O operations when the kernel_thread is * already awake but potentially shifted to TASK_INTERRUPTIBLE state. */ -static int hvcs_kicked = 0; +static int hvcs_kicked; -/* Used the the kthread construct for task operations */ +/* + * Use by the kthread construct for task operations like waking the sleeping + * thread and stopping the kthread. + */ static struct task_struct *hvcs_task; /* @@ -223,7 +256,8 @@ static struct task_struct *hvcs_task; */ static unsigned long *hvcs_pi_buff; -static spinlock_t hvcs_pi_lock; +/* Only allow one hvcs_struct to use the hvcs_pi_buff at a time. */ +static spinlock_t hvcs_pi_lock = SPIN_LOCK_UNLOCKED; /* One vty-server per hvcs_struct */ struct hvcs_struct { @@ -263,9 +297,9 @@ struct hvcs_struct { */ struct kobject kobj; /* ref count & hvcs_struct lifetime */ int connected; /* is the vty-server currently connected to a vty? */ - unsigned int p_unit_address; /* partner unit address */ - unsigned int p_partition_ID; /* partner partition ID */ - char p_location_code[CLC_LENGTH]; + uint32_t p_unit_address; /* partner unit address */ + uint32_t p_partition_ID; /* partner partition ID */ + char p_location_code[HVCS_CLC_LENGTH + 1]; /* CLC + Null Term */ struct list_head next; /* list management */ struct vio_dev *vdev; }; @@ -274,7 +308,7 @@ struct hvcs_struct { #define from_kobj(kobj) container_of(kobj, struct hvcs_struct, kobj) static struct list_head hvcs_structs = LIST_HEAD_INIT(hvcs_structs); -static spinlock_t hvcs_structs_lock; +static spinlock_t hvcs_structs_lock = SPIN_LOCK_UNLOCKED; static void hvcs_unthrottle(struct tty_struct *tty); static void hvcs_throttle(struct tty_struct *tty); @@ -297,7 +331,6 @@ static void hvcs_partner_free(struct hvcs_struct *hvcsd); static int hvcs_enable_device(struct hvcs_struct *hvcsd, uint32_t unit_address, unsigned int irq, struct vio_dev *dev); -static void hvcs_final_close(struct hvcs_struct *hvcsd); static void destroy_hvcs_struct(struct kobject *kobj); static int hvcs_open(struct tty_struct *tty, struct file *filp); @@ -357,12 +390,11 @@ static irqreturn_t hvcs_handle_interrupt(int irq, void *dev_instance, struct pt_regs *regs) { struct hvcs_struct *hvcsd = dev_instance; - unsigned long flags; - spin_lock_irqsave(&hvcsd->lock, flags); + spin_lock(&hvcsd->lock); vio_disable_interrupts(hvcsd->vdev); hvcsd->todo_mask |= HVCS_SCHED_READ; - spin_unlock_irqrestore(&hvcsd->lock, flags); + spin_unlock(&hvcsd->lock); hvcs_kick(); return IRQ_HANDLED; @@ -371,7 +403,7 @@ static irqreturn_t hvcs_handle_interrupt(int irq, void *dev_instance, /* This function must be called with the hvcsd->lock held */ static void hvcs_try_write(struct hvcs_struct *hvcsd) { - unsigned int unit_address = hvcsd->vdev->unit_address; + uint32_t unit_address = hvcsd->vdev->unit_address; struct tty_struct *tty = hvcsd->tty; int sent; @@ -382,9 +414,9 @@ static void hvcs_try_write(struct hvcs_struct *hvcsd) hvcsd->chars_in_buffer ); if (sent > 0) { hvcsd->chars_in_buffer = 0; - wmb(); + /* wmb(); */ hvcsd->todo_mask &= ~(HVCS_TRY_WRITE); - wmb(); + /* wmb(); */ /* * We are still obligated to deliver the data to the @@ -393,10 +425,7 @@ static void hvcs_try_write(struct hvcs_struct *hvcsd) * a non-existent tty. */ if (tty) { - if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) - && tty->ldisc.write_wakeup) - (tty->ldisc.write_wakeup) (tty); - wake_up_interruptible(&tty->write_wait); + tty_wakeup(tty); } } } @@ -404,11 +433,11 @@ static void hvcs_try_write(struct hvcs_struct *hvcsd) static int hvcs_io(struct hvcs_struct *hvcsd) { - unsigned int unit_address; + uint32_t unit_address; struct tty_struct *tty; char buf[HVCS_BUFF_LEN] __ALIGNED__; unsigned long flags; - int got; + int got = 0; int i; spin_lock_irqsave(&hvcsd->lock, flags); @@ -461,11 +490,8 @@ static int hvcs_io(struct hvcs_struct *hvcsd) static int khvcsd(void *unused) { - struct hvcs_struct *hvcsd = NULL; - struct list_head *element; - struct list_head *safe_temp; + struct hvcs_struct *hvcsd; int hvcs_todo_mask; - unsigned long structs_flags; __set_current_state(TASK_RUNNING); @@ -474,12 +500,11 @@ static int khvcsd(void *unused) hvcs_kicked = 0; wmb(); - spin_lock_irqsave(&hvcs_structs_lock, structs_flags); - list_for_each_safe(element, safe_temp, &hvcs_structs) { - hvcsd = list_entry(element, struct hvcs_struct, next); - hvcs_todo_mask |= hvcs_io(hvcsd); + spin_lock(&hvcs_structs_lock); + list_for_each_entry(hvcsd, &hvcs_structs, next) { + hvcs_todo_mask |= hvcs_io(hvcsd); } - spin_unlock_irqrestore(&hvcs_structs_lock, structs_flags); + spin_unlock(&hvcs_structs_lock); /* * If any of the hvcs adapters want to try a write or quick read @@ -506,6 +531,19 @@ static struct vio_device_id hvcs_driver_table[] __devinitdata= { }; MODULE_DEVICE_TABLE(vio, hvcs_driver_table); +static void hvcs_return_index(int index) +{ + /* Paranoia check */ + if (!hvcs_index_list) + return; + if (index < 0 || index >= hvcs_index_count) + return; + if (hvcs_index_list[index] == -1) + return; + else + hvcs_index_list[index] = -1; +} + /* callback when the kboject ref count reaches zero */ static void destroy_hvcs_struct(struct kobject *kobj) { @@ -513,6 +551,7 @@ static void destroy_hvcs_struct(struct kobject *kobj) struct vio_dev *vdev; unsigned long flags; + spin_lock(&hvcs_structs_lock); spin_lock_irqsave(&hvcsd->lock, flags); /* the list_del poisons the pointers */ @@ -524,7 +563,7 @@ static void destroy_hvcs_struct(struct kobject *kobj) " partner vty@%X:%d connection.\n", hvcsd->vdev->unit_address, hvcsd->p_unit_address, - (unsigned int)hvcsd->p_partition_ID); + (uint32_t)hvcsd->p_partition_ID); } printk(KERN_INFO "HVCS: Destroyed hvcs_struct for vty-server@%X.\n", hvcsd->vdev->unit_address); @@ -534,55 +573,60 @@ static void destroy_hvcs_struct(struct kobject *kobj) hvcsd->p_unit_address = 0; hvcsd->p_partition_ID = 0; - memset(&hvcsd->p_location_code[0], 0x00, CLC_LENGTH); + hvcs_return_index(hvcsd->index); + memset(&hvcsd->p_location_code[0], 0x00, HVCS_CLC_LENGTH + 1); spin_unlock_irqrestore(&hvcsd->lock, flags); + spin_unlock(&hvcs_structs_lock); hvcs_remove_device_attrs(vdev); kfree(hvcsd); } -/* This function must be called with hvcsd->lock held. */ -static void hvcs_final_close(struct hvcs_struct *hvcsd) -{ - vio_disable_interrupts(hvcsd->vdev); - free_irq(hvcsd->vdev->irq, hvcsd); - - hvcsd->todo_mask = 0; - - /* These two may be redundant if the operation was a close. */ - if (hvcsd->tty) { - hvcsd->tty->driver_data = NULL; - hvcsd->tty = NULL; - } - - hvcsd->open_count = 0; - - memset(&hvcsd->buffer[0], 0x00, HVCS_BUFF_LEN); - hvcsd->chars_in_buffer = 0; -} - static struct kobj_type hvcs_kobj_type = { .release = destroy_hvcs_struct, }; +static int hvcs_get_index(void) +{ + int i; + /* Paranoia check */ + if (!hvcs_index_list) { + printk(KERN_ERR "HVCS: hvcs_index_list NOT valid!.\n"); + return -EFAULT; + } + /* Find the numerically lowest first free index. */ + for(i = 0; i < hvcs_index_count; i++) { + if (hvcs_index_list[i] == -1) { + hvcs_index_list[i] = 0; + return i; + } + } + return -1; +} + static int __devinit hvcs_probe( struct vio_dev *dev, const struct vio_device_id *id) { struct hvcs_struct *hvcsd; - unsigned long structs_flags; + int index; if (!dev || !id) { printk(KERN_ERR "HVCS: probed with invalid parameter.\n"); return -EPERM; } + /* early to avoid cleanup on failure */ + index = hvcs_get_index(); + if (index < 0) { + return -EFAULT; + } + hvcsd = kmalloc(sizeof(*hvcsd), GFP_KERNEL); - if (!hvcsd) { + if (!hvcsd) return -ENODEV; - } /* hvcsd->tty is zeroed out with the memset */ memset(hvcsd, 0x00, sizeof(*hvcsd)); @@ -596,7 +640,9 @@ static int __devinit hvcs_probe( hvcsd->vdev = dev; dev->dev.driver_data = hvcsd; - hvcsd->index = ++hvcs_struct_count; + hvcsd->index = index; + + /* hvcsd->index = ++hvcs_struct_count; */ hvcsd->chars_in_buffer = 0; hvcsd->todo_mask = 0; hvcsd->connected = 0; @@ -617,15 +663,15 @@ static int __devinit hvcs_probe( * will get -ENODEV. */ - spin_lock_irqsave(&hvcs_structs_lock, structs_flags); + spin_lock(&hvcs_structs_lock); list_add_tail(&(hvcsd->next), &hvcs_structs); - spin_unlock_irqrestore(&hvcs_structs_lock, structs_flags); + spin_unlock(&hvcs_structs_lock); hvcs_create_device_attrs(hvcsd); - printk(KERN_INFO "HVCS: Added vty-server@%X.\n", dev->unit_address); + printk(KERN_INFO "HVCS: vty-server@%X added to the vio bus.\n", dev->unit_address); /* * DON'T enable interrupts here because there is no user to receive the @@ -688,8 +734,8 @@ static void hvcs_set_pi(struct hvcs_partner_info *pi, struct hvcs_struct *hvcsd) hvcsd->p_unit_address = pi->unit_address; hvcsd->p_partition_ID = pi->partition_ID; clclength = strlen(&pi->location_code[0]); - if (clclength > CLC_LENGTH - 1) - clclength = CLC_LENGTH - 1; + if (clclength > HVCS_CLC_LENGTH) + clclength = HVCS_CLC_LENGTH; /* copy the null-term char too */ strncpy(&hvcsd->p_location_code[0], @@ -711,20 +757,18 @@ static void hvcs_set_pi(struct hvcs_partner_info *pi, struct hvcs_struct *hvcsd) */ static int hvcs_get_pi(struct hvcs_struct *hvcsd) { - /* struct hvcs_partner_info *head_pi = NULL; */ - struct hvcs_partner_info *pi = NULL; - unsigned int unit_address = hvcsd->vdev->unit_address; + struct hvcs_partner_info *pi; + uint32_t unit_address = hvcsd->vdev->unit_address; struct list_head head; - unsigned long flags; int retval; - spin_lock_irqsave(&hvcs_pi_lock, flags); + spin_lock(&hvcs_pi_lock); if (!hvcs_pi_buff) { - spin_unlock_irqrestore(&hvcs_pi_lock, flags); + spin_unlock(&hvcs_pi_lock); return -EFAULT; } retval = hvcs_get_partner_info(unit_address, &head, hvcs_pi_buff); - spin_unlock_irqrestore(&hvcs_pi_lock, flags); + spin_unlock(&hvcs_pi_lock); if (retval) { printk(KERN_ERR "HVCS: Failed to fetch partner" " info for vty-server@%x.\n", unit_address); @@ -748,11 +792,10 @@ static int hvcs_get_pi(struct hvcs_struct *hvcsd) */ static int hvcs_rescan_devices_list(void) { - struct hvcs_struct *hvcsd = NULL; + struct hvcs_struct *hvcsd; unsigned long flags; - unsigned long structs_flags; - spin_lock_irqsave(&hvcs_structs_lock, structs_flags); + spin_lock(&hvcs_structs_lock); list_for_each_entry(hvcsd, &hvcs_structs, next) { spin_lock_irqsave(&hvcsd->lock, flags); @@ -760,7 +803,7 @@ static int hvcs_rescan_devices_list(void) spin_unlock_irqrestore(&hvcsd->lock, flags); } - spin_unlock_irqrestore(&hvcs_structs_lock, structs_flags); + spin_unlock(&hvcs_structs_lock); return 0; } @@ -848,13 +891,14 @@ static int hvcs_enable_device(struct hvcs_struct *hvcsd, uint32_t unit_address, unsigned int irq, struct vio_dev *vdev) { unsigned long flags; + int rc; /* * It is possible that the vty-server was removed between the time that * the conn was registered and now. */ - if (!request_irq(irq, &hvcs_handle_interrupt, - SA_INTERRUPT, "ibmhvcs", hvcsd)) { + if (!(rc = request_irq(irq, &hvcs_handle_interrupt, + SA_INTERRUPT, "ibmhvcs", hvcsd))) { /* * It is possible the vty-server was removed after the irq was * requested but before we have time to enable interrupts. @@ -874,7 +918,7 @@ static int hvcs_enable_device(struct hvcs_struct *hvcsd, uint32_t unit_address, hvcs_partner_free(hvcsd); spin_unlock_irqrestore(&hvcsd->lock, flags); - return -ENODEV; + return rc; } @@ -888,22 +932,17 @@ static int hvcs_enable_device(struct hvcs_struct *hvcsd, uint32_t unit_address, struct hvcs_struct *hvcs_get_by_index(int index) { struct hvcs_struct *hvcsd = NULL; - struct list_head *element; - struct list_head *safe_temp; unsigned long flags; - unsigned long structs_flags; - spin_lock_irqsave(&hvcs_structs_lock, structs_flags); + spin_lock(&hvcs_structs_lock); /* We can immediately discard OOB requests */ if (index >= 0 && index < HVCS_MAX_SERVER_ADAPTERS) { - list_for_each_safe(element, safe_temp, &hvcs_structs) { - hvcsd = list_entry(element, struct hvcs_struct, next); + list_for_each_entry(hvcsd, &hvcs_structs, next) { spin_lock_irqsave(&hvcsd->lock, flags); if (hvcsd->index == index) { kobject_get(&hvcsd->kobj); spin_unlock_irqrestore(&hvcsd->lock, flags); - spin_unlock_irqrestore(&hvcs_structs_lock, - structs_flags); + spin_unlock(&hvcs_structs_lock); return hvcsd; } spin_unlock_irqrestore(&hvcsd->lock, flags); @@ -911,7 +950,7 @@ struct hvcs_struct *hvcs_get_by_index(int index) hvcsd = NULL; } - spin_unlock_irqrestore(&hvcs_structs_lock, structs_flags); + spin_unlock(&hvcs_structs_lock); return hvcsd; } @@ -921,12 +960,13 @@ struct hvcs_struct *hvcs_get_by_index(int index) */ static int hvcs_open(struct tty_struct *tty, struct file *filp) { - struct hvcs_struct *hvcsd = NULL; - int retval = 0; + struct hvcs_struct *hvcsd; + int rc, retval = 0; unsigned long flags; unsigned int irq; struct vio_dev *vdev; unsigned long unit_address; + struct kobject *kobjp; if (tty->driver_data) goto fast_open; @@ -936,7 +976,8 @@ static int hvcs_open(struct tty_struct *tty, struct file *filp) * This function increments the kobject index. */ if (!(hvcsd = hvcs_get_by_index(tty->index))) { - printk(KERN_WARNING "HVCS: open failed, no index.\n"); + printk(KERN_WARNING "HVCS: open failed, no device associated" + " with tty->index %d.\n", tty->index); return -ENODEV; } @@ -959,7 +1000,7 @@ static int hvcs_open(struct tty_struct *tty, struct file *filp) */ tty->low_latency = 1; - memset(&hvcsd->buffer[0], 0x3F, HVCS_BUFF_LEN); + memset(&hvcsd->buffer[0], 0x00, HVCS_BUFF_LEN); /* * Save these in the spinlock for the enable operations that need them @@ -974,12 +1015,12 @@ static int hvcs_open(struct tty_struct *tty, struct file *filp) /* * This must be done outside of the spinlock because it requests irqs - * and will grab the spinlcok and free the connection if it fails. + * and will grab the spinlock and free the connection if it fails. */ - if ((hvcs_enable_device(hvcsd, unit_address, irq, vdev))) { + if (((rc = hvcs_enable_device(hvcsd, unit_address, irq, vdev)))) { kobject_put(&hvcsd->kobj); printk(KERN_WARNING "HVCS: enable device failed.\n"); - return -ENODEV; + return rc; } goto open_success; @@ -1002,16 +1043,17 @@ fast_open: open_success: hvcs_kick(); - printk(KERN_INFO "HVCS: vty-server@%X opened.\n", + printk(KERN_INFO "HVCS: vty-server@%X connection opened.\n", hvcsd->vdev->unit_address ); return 0; error_release: + kobjp = &hvcsd->kobj; spin_unlock_irqrestore(&hvcsd->lock, flags); kobject_put(&hvcsd->kobj); - printk(KERN_WARNING "HVCS: HVCS partner connect failed.\n"); + printk(KERN_WARNING "HVCS: partner connect failed.\n"); return retval; } @@ -1020,6 +1062,7 @@ static void hvcs_close(struct tty_struct *tty, struct file *filp) struct hvcs_struct *hvcsd; unsigned long flags; struct kobject *kobjp; + int irq = NO_IRQ; /* * Is someone trying to close the file associated with this device after @@ -1039,14 +1082,10 @@ static void hvcs_close(struct tty_struct *tty, struct file *filp) hvcsd = tty->driver_data; spin_lock_irqsave(&hvcsd->lock, flags); + kobjp = &hvcsd->kobj; if (--hvcsd->open_count == 0) { - /* - * This line is important because it tells hvcs_open that this - * device needs to be re-configured the next time hvcs_open is - * called. - */ - hvcsd->tty->driver_data = NULL; + vio_disable_interrupts(hvcsd->vdev); /* * NULL this early so that the kernel_thread doesn't try to @@ -1055,34 +1094,28 @@ static void hvcs_close(struct tty_struct *tty, struct file *filp) */ hvcsd->tty = NULL; - /* - * Block the close until all the buffered data has been - * delivered. - */ - while(hvcsd->chars_in_buffer) { - spin_unlock_irqrestore(&hvcsd->lock, flags); + irq = hvcsd->vdev->irq; + spin_unlock_irqrestore(&hvcsd->lock, flags); - /* - * Give the kernel thread the hvcs_struct so that it can - * try to deliver the remaining data but block the close - * operation by spinning in this function so that other - * tty operations have to wait. - */ - yield(); - spin_lock_irqsave(&hvcsd->lock, flags); - } + tty_wait_until_sent(tty, HVCS_CLOSE_WAIT); - hvcs_final_close(hvcsd); + /* + * This line is important because it tells hvcs_open that this + * device needs to be re-configured the next time hvcs_open is + * called. + */ + tty->driver_data = NULL; + free_irq(irq, hvcsd); + kobject_put(kobjp); + return; } else if (hvcsd->open_count < 0) { printk(KERN_ERR "HVCS: vty-server@%X open_count: %d" " is missmanaged.\n", - hvcsd->vdev->unit_address, hvcsd->open_count); + hvcsd->vdev->unit_address, hvcsd->open_count); } - kobjp = &hvcsd->kobj; spin_unlock_irqrestore(&hvcsd->lock, flags); - kobject_put(kobjp); } @@ -1092,6 +1125,7 @@ static void hvcs_hangup(struct tty_struct * tty) unsigned long flags; int temp_open_count; struct kobject *kobjp; + int irq = NO_IRQ; spin_lock_irqsave(&hvcsd->lock, flags); /* Preserve this so that we know how many kobject refs to put */ @@ -1101,15 +1135,31 @@ static void hvcs_hangup(struct tty_struct * tty) * Don't kobject put inside the spinlock because the destruction * callback may use the spinlock and it may get called before the * spinlock has been released. Get a pointer to the kobject and - * kobject_put on that instead. + * kobject_put on that after releasing the spinlock. */ kobjp = &hvcsd->kobj; - /* Calling this will drop any buffered data on the floor. */ - hvcs_final_close(hvcsd); + vio_disable_interrupts(hvcsd->vdev); + + hvcsd->todo_mask = 0; + + /* I don't think the tty needs the hvcs_struct pointer after a hangup */ + hvcsd->tty->driver_data = NULL; + hvcsd->tty = NULL; + + hvcsd->open_count = 0; + + /* This will drop any buffered data on the floor which is OK in a hangup + * scenario. */ + memset(&hvcsd->buffer[0], 0x00, HVCS_BUFF_LEN); + hvcsd->chars_in_buffer = 0; + + irq = hvcsd->vdev->irq; spin_unlock_irqrestore(&hvcsd->lock, flags); + free_irq(irq, hvcsd); + /* * We need to kobject_put() for every open_count we have since the * tty_hangup() function doesn't invoke a close per open connection on a @@ -1259,28 +1309,18 @@ static int hvcs_write(struct tty_struct *tty, int from_user, static int hvcs_write_room(struct tty_struct *tty) { struct hvcs_struct *hvcsd = tty->driver_data; - unsigned long flags; - int retval; if (!hvcsd || hvcsd->open_count <= 0) return 0; - spin_lock_irqsave(&hvcsd->lock, flags); - retval = HVCS_BUFF_LEN - hvcsd->chars_in_buffer; - spin_unlock_irqrestore(&hvcsd->lock, flags); - return retval; + return HVCS_BUFF_LEN - hvcsd->chars_in_buffer; } static int hvcs_chars_in_buffer(struct tty_struct *tty) { struct hvcs_struct *hvcsd = tty->driver_data; - unsigned long flags; - int retval; - spin_lock_irqsave(&hvcsd->lock, flags); - retval = hvcsd->chars_in_buffer; - spin_unlock_irqrestore(&hvcsd->lock, flags); - return retval; + return hvcsd->chars_in_buffer; } static struct tty_operations hvcs_ops = { @@ -1294,6 +1334,28 @@ static struct tty_operations hvcs_ops = { .throttle = hvcs_throttle, }; +static int hvcs_alloc_index_list(int n) +{ + int i; + hvcs_index_list = kmalloc(n * sizeof(hvcs_index_count),GFP_KERNEL); + if (!hvcs_index_list) + return -ENOMEM; + hvcs_index_count = n; + for(i = 0; i < hvcs_index_count; i++) + hvcs_index_list[i] = -1; + return 0; +} + +static void hvcs_free_index_list(void) +{ + /* Paranoia check to be thorough. */ + if (hvcs_index_list) { + kfree(hvcs_index_list); + hvcs_index_list = NULL; + hvcs_index_count = 0; + } +} + static int __init hvcs_module_init(void) { int rc; @@ -1312,6 +1374,9 @@ static int __init hvcs_module_init(void) if (!hvcs_tty_driver) return -ENOMEM; + if (hvcs_alloc_index_list(num_ttys_to_alloc)) + return -ENOMEM; + hvcs_tty_driver->owner = THIS_MODULE; hvcs_tty_driver->driver_name = hvcs_driver_name; @@ -1342,19 +1407,25 @@ static int __init hvcs_module_init(void) if (tty_register_driver(hvcs_tty_driver)) { printk(KERN_ERR "HVCS: registration " " as a tty driver failed.\n"); + hvcs_free_index_list(); put_tty_driver(hvcs_tty_driver); - return rc; + return -EIO; } - hvcs_structs_lock = SPIN_LOCK_UNLOCKED; - - hvcs_pi_lock = SPIN_LOCK_UNLOCKED; hvcs_pi_buff = kmalloc(PAGE_SIZE, GFP_KERNEL); + if (!hvcs_pi_buff) { + tty_unregister_driver(hvcs_tty_driver); + hvcs_free_index_list(); + put_tty_driver(hvcs_tty_driver); + return -ENOMEM; + } hvcs_task = kthread_run(khvcsd, NULL, "khvcsd"); if (IS_ERR(hvcs_task)) { - printk("khvcsd creation failed. Driver not loaded.\n"); + printk(KERN_ERR "HVCS: khvcsd creation failed. Driver not loaded.\n"); kfree(hvcs_pi_buff); + tty_unregister_driver(hvcs_tty_driver); + hvcs_free_index_list(); put_tty_driver(hvcs_tty_driver); return -EIO; } @@ -1374,8 +1445,6 @@ static int __init hvcs_module_init(void) static void __exit hvcs_module_exit(void) { - unsigned long flags; - /* * This driver receives hvcs_remove callbacks for each device upon * module removal. @@ -1387,10 +1456,10 @@ static void __exit hvcs_module_exit(void) */ kthread_stop(hvcs_task); - spin_lock_irqsave(&hvcs_pi_lock, flags); + spin_lock(&hvcs_pi_lock); kfree(hvcs_pi_buff); hvcs_pi_buff = NULL; - spin_unlock_irqrestore(&hvcs_pi_lock, flags); + spin_unlock(&hvcs_pi_lock); hvcs_remove_driver_attrs(); @@ -1398,6 +1467,8 @@ static void __exit hvcs_module_exit(void) tty_unregister_driver(hvcs_tty_driver); + hvcs_free_index_list(); + put_tty_driver(hvcs_tty_driver); printk(KERN_INFO "HVCS: driver module removed.\n"); @@ -1499,7 +1570,7 @@ static ssize_t hvcs_vterm_state_store(struct device *dev, const char *buf, " partner vty@%X:%d connection.\n", hvcsd->vdev->unit_address, hvcsd->p_unit_address, - (unsigned int)hvcsd->p_partition_ID); + (uint32_t)hvcsd->p_partition_ID); spin_unlock_irqrestore(&hvcsd->lock, flags); return count; @@ -1520,11 +1591,27 @@ static ssize_t hvcs_vterm_state_show(struct device *dev, char *buf) static DEVICE_ATTR(vterm_state, S_IRUGO | S_IWUSR, hvcs_vterm_state_show, hvcs_vterm_state_store); +static ssize_t hvcs_index_show(struct device *dev, char *buf) +{ + struct vio_dev *viod = to_vio_dev(dev); + struct hvcs_struct *hvcsd = from_vio_dev(viod); + unsigned long flags; + int retval; + + spin_lock_irqsave(&hvcsd->lock, flags); + retval = sprintf(buf, "%d\n", hvcsd->index); + spin_unlock_irqrestore(&hvcsd->lock, flags); + return retval; +} + +static DEVICE_ATTR(index, S_IRUGO, hvcs_index_show, NULL); + static struct attribute *hvcs_attrs[] = { &dev_attr_partner_vtys.attr, &dev_attr_partner_clcs.attr, &dev_attr_current_vty.attr, &dev_attr_vterm_state.attr, + &dev_attr_index.attr, NULL, };