diff options
Diffstat (limited to 'drivers/s390/char/sclp.c')
| -rw-r--r-- | drivers/s390/char/sclp.c | 471 |
1 files changed, 401 insertions, 70 deletions
diff --git a/drivers/s390/char/sclp.c b/drivers/s390/char/sclp.c index 4377e93a43d..c316051d9bd 100644 --- a/drivers/s390/char/sclp.c +++ b/drivers/s390/char/sclp.c @@ -1,13 +1,13 @@ /* - * drivers/s390/char/sclp.c - * core function to access sclp interface + * core function to access sclp interface * - * S390 version - * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation - * Author(s): Martin Peschke <mpeschke@de.ibm.com> - * Martin Schwidefsky <schwidefsky@de.ibm.com> + * Copyright IBM Corp. 1999, 2009 + * + * Author(s): Martin Peschke <mpeschke@de.ibm.com> + * Martin Schwidefsky <schwidefsky@de.ibm.com> */ +#include <linux/kernel_stat.h> #include <linux/module.h> #include <linux/err.h> #include <linux/spinlock.h> @@ -16,16 +16,16 @@ #include <linux/reboot.h> #include <linux/jiffies.h> #include <linux/init.h> +#include <linux/suspend.h> +#include <linux/completion.h> +#include <linux/platform_device.h> #include <asm/types.h> -#include <asm/s390_ext.h> +#include <asm/irq.h> #include "sclp.h" #define SCLP_HEADER "sclp: " -/* Structure for register_early_external_interrupt. */ -static ext_int_info_t ext_int_info_hwc; - /* Lock to protect internal data consistency. */ static DEFINE_SPINLOCK(sclp_lock); @@ -47,9 +47,53 @@ static struct sclp_req sclp_init_req; static char sclp_read_sccb[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); static char sclp_init_sccb[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); +/* Suspend request */ +static DECLARE_COMPLETION(sclp_request_queue_flushed); + +/* Number of console pages to allocate, used by sclp_con.c and sclp_vt220.c */ +int sclp_console_pages = SCLP_CONSOLE_PAGES; +/* Flag to indicate if buffer pages are dropped on buffer full condition */ +int sclp_console_drop = 0; +/* Number of times the console dropped buffer pages */ +unsigned long sclp_console_full; + +static void sclp_suspend_req_cb(struct sclp_req *req, void *data) +{ + complete(&sclp_request_queue_flushed); +} + +static int __init sclp_setup_console_pages(char *str) +{ + int pages, rc; + + rc = kstrtoint(str, 0, &pages); + if (!rc && pages >= SCLP_CONSOLE_PAGES) + sclp_console_pages = pages; + return 1; +} + +__setup("sclp_con_pages=", sclp_setup_console_pages); + +static int __init sclp_setup_console_drop(char *str) +{ + int drop, rc; + + rc = kstrtoint(str, 0, &drop); + if (!rc && drop) + sclp_console_drop = 1; + return 1; +} + +__setup("sclp_con_drop=", sclp_setup_console_drop); + +static struct sclp_req sclp_suspend_req; + /* Timer for request retries. */ static struct timer_list sclp_request_timer; +/* Timer for queued requests. */ +static struct timer_list sclp_queue_timer; + /* Internal state: is the driver initialized? */ static volatile enum sclp_init_state_t { sclp_init_state_uninitialized, @@ -84,6 +128,12 @@ static volatile enum sclp_mask_state_t { sclp_mask_state_initializing } sclp_mask_state = sclp_mask_state_idle; +/* Internal state: is the driver suspended? */ +static enum sclp_suspend_state_t { + sclp_suspend_state_running, + sclp_suspend_state_suspended, +} sclp_suspend_state = sclp_suspend_state_running; + /* Maximum retry counts */ #define SCLP_INIT_RETRY 3 #define SCLP_MASK_RETRY 3 @@ -101,14 +151,19 @@ static int sclp_init(void); int sclp_service_call(sclp_cmdw_t command, void *sccb) { - int cc; + int cc = 4; /* Initialize for program check handling */ asm volatile( - " .insn rre,0xb2200000,%1,%2\n" /* servc %1,%2 */ - " ipm %0\n" - " srl %0,28" - : "=&d" (cc) : "d" (command), "a" (__pa(sccb)) + "0: .insn rre,0xb2200000,%1,%2\n" /* servc %1,%2 */ + "1: ipm %0\n" + " srl %0,28\n" + "2:\n" + EX_TABLE(0b, 2b) + EX_TABLE(1b, 2b) + : "+&d" (cc) : "d" (command), "a" (__pa(sccb)) : "cc", "memory"); + if (cc == 4) + return -EINVAL; if (cc == 3) return -EIO; if (cc == 2) @@ -163,6 +218,76 @@ sclp_request_timeout(unsigned long data) sclp_process_queue(); } +/* + * Returns the expire value in jiffies of the next pending request timeout, + * if any. Needs to be called with sclp_lock. + */ +static unsigned long __sclp_req_queue_find_next_timeout(void) +{ + unsigned long expires_next = 0; + struct sclp_req *req; + + list_for_each_entry(req, &sclp_req_queue, list) { + if (!req->queue_expires) + continue; + if (!expires_next || + (time_before(req->queue_expires, expires_next))) + expires_next = req->queue_expires; + } + return expires_next; +} + +/* + * Returns expired request, if any, and removes it from the list. + */ +static struct sclp_req *__sclp_req_queue_remove_expired_req(void) +{ + unsigned long flags, now; + struct sclp_req *req; + + spin_lock_irqsave(&sclp_lock, flags); + now = jiffies; + /* Don't need list_for_each_safe because we break out after list_del */ + list_for_each_entry(req, &sclp_req_queue, list) { + if (!req->queue_expires) + continue; + if (time_before_eq(req->queue_expires, now)) { + if (req->status == SCLP_REQ_QUEUED) { + req->status = SCLP_REQ_QUEUED_TIMEOUT; + list_del(&req->list); + goto out; + } + } + } + req = NULL; +out: + spin_unlock_irqrestore(&sclp_lock, flags); + return req; +} + +/* + * Timeout handler for queued requests. Removes request from list and + * invokes callback. This timer can be set per request in situations where + * waiting too long would be harmful to the system, e.g. during SE reboot. + */ +static void sclp_req_queue_timeout(unsigned long data) +{ + unsigned long flags, expires_next; + struct sclp_req *req; + + do { + req = __sclp_req_queue_remove_expired_req(); + if (req && req->callback) + req->callback(req, req->callback_data); + } while (req); + + spin_lock_irqsave(&sclp_lock, flags); + expires_next = __sclp_req_queue_find_next_timeout(); + if (expires_next) + mod_timer(&sclp_queue_timer, expires_next); + spin_unlock_irqrestore(&sclp_lock, flags); +} + /* Try to start a request. Return zero if the request was successfully * started or if it will be started at a later time. Return non-zero otherwise. * Called while sclp_lock is locked. */ @@ -178,7 +303,7 @@ __sclp_start_request(struct sclp_req *req) req->start_count++; if (rc == 0) { - /* Sucessfully started request */ + /* Successfully started request */ req->status = SCLP_REQ_RUNNING; sclp_running_state = sclp_running_state_running; __sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ, @@ -211,6 +336,8 @@ sclp_process_queue(void) del_timer(&sclp_request_timer); while (!list_empty(&sclp_req_queue)) { req = list_entry(sclp_req_queue.next, struct sclp_req, list); + if (!req->sccb) + goto do_post; rc = __sclp_start_request(req); if (rc == 0) break; @@ -222,6 +349,7 @@ sclp_process_queue(void) sclp_request_timeout, 0); break; } +do_post: /* Post-processing for aborted request */ list_del(&req->list); if (req->callback) { @@ -233,6 +361,19 @@ sclp_process_queue(void) spin_unlock_irqrestore(&sclp_lock, flags); } +static int __sclp_can_add_request(struct sclp_req *req) +{ + if (req == &sclp_suspend_req || req == &sclp_init_req) + return 1; + if (sclp_suspend_state != sclp_suspend_state_running) + return 0; + if (sclp_init_state != sclp_init_state_initialized) + return 0; + if (sclp_activation_state != sclp_activation_state_active) + return 0; + return 1; +} + /* Queue a new request. Return zero on success, non-zero otherwise. */ int sclp_add_request(struct sclp_req *req) @@ -241,9 +382,7 @@ sclp_add_request(struct sclp_req *req) int rc; spin_lock_irqsave(&sclp_lock, flags); - if ((sclp_init_state != sclp_init_state_initialized || - sclp_activation_state != sclp_activation_state_active) && - req != &sclp_init_req) { + if (!__sclp_can_add_request(req)) { spin_unlock_irqrestore(&sclp_lock, flags); return -EIO; } @@ -251,13 +390,26 @@ sclp_add_request(struct sclp_req *req) req->start_count = 0; list_add_tail(&req->list, &sclp_req_queue); rc = 0; + if (req->queue_timeout) { + req->queue_expires = jiffies + req->queue_timeout * HZ; + if (!timer_pending(&sclp_queue_timer) || + time_after(sclp_queue_timer.expires, req->queue_expires)) + mod_timer(&sclp_queue_timer, req->queue_expires); + } else + req->queue_expires = 0; /* Start if request is first in list */ if (sclp_running_state == sclp_running_state_idle && req->list.prev == &sclp_req_queue) { + if (!req->sccb) { + list_del(&req->list); + rc = -ENODATA; + goto out; + } rc = __sclp_start_request(req); if (rc) list_del(&req->list); } +out: spin_unlock_irqrestore(&sclp_lock, flags); return rc; } @@ -298,7 +450,7 @@ sclp_dispatch_evbufs(struct sccb_header *sccb) reg->receiver_fn(evbuf); spin_lock_irqsave(&sclp_lock, flags); } else if (reg == NULL) - rc = -ENOSYS; + rc = -EOPNOTSUPP; } spin_unlock_irqrestore(&sclp_lock, flags); return rc; @@ -357,16 +509,17 @@ __sclp_find_req(u32 sccb) /* Handler for external interruption. Perform request post-processing. * Prepare read event data request if necessary. Start processing of next * request on queue. */ -static void -sclp_interrupt_handler(__u16 code) +static void sclp_interrupt_handler(struct ext_code ext_code, + unsigned int param32, unsigned long param64) { struct sclp_req *req; u32 finished_sccb; u32 evbuf_pending; + inc_irq_stat(IRQEXT_SCP); spin_lock(&sclp_lock); - finished_sccb = S390_lowcore.ext_params & 0xfffffff8; - evbuf_pending = S390_lowcore.ext_params & 0x3; + finished_sccb = param32 & 0xfffffff8; + evbuf_pending = param32 & 0x3; if (finished_sccb) { del_timer(&sclp_request_timer); sclp_running_state = sclp_running_state_reset_pending; @@ -413,7 +566,7 @@ sclp_sync_wait(void) timeout = 0; if (timer_pending(&sclp_request_timer)) { /* Get timeout TOD value */ - timeout = get_clock() + + timeout = get_tod_clock_fast() + sclp_tod_from_jiffies(sclp_request_timer.expires - jiffies); } @@ -430,12 +583,12 @@ sclp_sync_wait(void) cr0_sync &= 0xffff00a0; cr0_sync |= 0x00000200; __ctl_load(cr0_sync, 0, 0); - __raw_local_irq_stosm(0x01); + __arch_local_irq_stosm(0x01); /* Loop until driver state indicates finished request */ while (sclp_running_state != sclp_running_state_idle) { /* Check for expired request timer */ if (timer_pending(&sclp_request_timer) && - get_clock() > timeout && + get_tod_clock_fast() > timeout && del_timer(&sclp_request_timer)) sclp_request_timer.function(sclp_request_timer.data); cpu_relax(); @@ -560,6 +713,7 @@ sclp_register(struct sclp_register *reg) /* Trigger initial state change callback */ reg->sclp_receive_mask = 0; reg->sclp_send_mask = 0; + reg->pm_event_posted = 0; list_add(®->list, &sclp_reg_list); spin_unlock_irqrestore(&sclp_lock, flags); rc = sclp_init_mask(1); @@ -616,16 +770,6 @@ sclp_remove_processed(struct sccb_header *sccb) EXPORT_SYMBOL(sclp_remove_processed); -struct init_sccb { - struct sccb_header header; - u16 _reserved; - u16 mask_length; - sccb_mask_t receive_mask; - sccb_mask_t send_mask; - sccb_mask_t sclp_receive_mask; - sccb_mask_t sclp_send_mask; -} __attribute__((packed)); - /* Prepare init mask request. Called while sclp_lock is locked. */ static inline void __sclp_make_init_req(u32 receive_mask, u32 send_mask) @@ -780,12 +924,13 @@ EXPORT_SYMBOL(sclp_reactivate); /* Handler for external interruption used during initialization. Modify * request state to done. */ -static void -sclp_check_handler(__u16 code) +static void sclp_check_handler(struct ext_code ext_code, + unsigned int param32, unsigned long param64) { u32 finished_sccb; - finished_sccb = S390_lowcore.ext_params & 0xfffffff8; + inc_irq_stat(IRQEXT_SCP); + finished_sccb = param32 & 0xfffffff8; /* Is this the interrupt we are waiting for? */ if (finished_sccb == 0) return; @@ -827,8 +972,7 @@ sclp_check_interface(void) spin_lock_irqsave(&sclp_lock, flags); /* Prepare init mask command */ - rc = register_early_external_interrupt(0x2401, sclp_check_handler, - &ext_int_info_hwc); + rc = register_external_irq(EXT_IRQ_SERVICE_SIG, sclp_check_handler); if (rc) { spin_unlock_irqrestore(&sclp_lock, flags); return rc; @@ -846,12 +990,12 @@ sclp_check_interface(void) spin_unlock_irqrestore(&sclp_lock, flags); /* Enable service-signal interruption - needs to happen * with IRQs enabled. */ - ctl_set_bit(0, 9); + irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL); /* Wait for signal from interrupt or timeout */ sclp_sync_wait(); /* Disable service-signal interruption - needs to happen * with IRQs enabled. */ - ctl_clear_bit(0,9); + irq_subclass_unregister(IRQ_SUBCLASS_SERVICE_SIGNAL); spin_lock_irqsave(&sclp_lock, flags); del_timer(&sclp_request_timer); if (sclp_init_req.status == SCLP_REQ_DONE && @@ -861,8 +1005,7 @@ sclp_check_interface(void) } else rc = -EBUSY; } - unregister_early_external_interrupt(0x2401, sclp_check_handler, - &ext_int_info_hwc); + unregister_external_irq(EXT_IRQ_SERVICE_SIG, sclp_check_handler); spin_unlock_irqrestore(&sclp_lock, flags); return rc; } @@ -880,63 +1023,251 @@ static struct notifier_block sclp_reboot_notifier = { .notifier_call = sclp_reboot_event }; +/* + * Suspend/resume SCLP notifier implementation + */ + +static void sclp_pm_event(enum sclp_pm_event sclp_pm_event, int rollback) +{ + struct sclp_register *reg; + unsigned long flags; + + if (!rollback) { + spin_lock_irqsave(&sclp_lock, flags); + list_for_each_entry(reg, &sclp_reg_list, list) + reg->pm_event_posted = 0; + spin_unlock_irqrestore(&sclp_lock, flags); + } + do { + spin_lock_irqsave(&sclp_lock, flags); + list_for_each_entry(reg, &sclp_reg_list, list) { + if (rollback && reg->pm_event_posted) + goto found; + if (!rollback && !reg->pm_event_posted) + goto found; + } + spin_unlock_irqrestore(&sclp_lock, flags); + return; +found: + spin_unlock_irqrestore(&sclp_lock, flags); + if (reg->pm_event_fn) + reg->pm_event_fn(reg, sclp_pm_event); + reg->pm_event_posted = rollback ? 0 : 1; + } while (1); +} + +/* + * Susend/resume callbacks for platform device + */ + +static int sclp_freeze(struct device *dev) +{ + unsigned long flags; + int rc; + + sclp_pm_event(SCLP_PM_EVENT_FREEZE, 0); + + spin_lock_irqsave(&sclp_lock, flags); + sclp_suspend_state = sclp_suspend_state_suspended; + spin_unlock_irqrestore(&sclp_lock, flags); + + /* Init supend data */ + memset(&sclp_suspend_req, 0, sizeof(sclp_suspend_req)); + sclp_suspend_req.callback = sclp_suspend_req_cb; + sclp_suspend_req.status = SCLP_REQ_FILLED; + init_completion(&sclp_request_queue_flushed); + + rc = sclp_add_request(&sclp_suspend_req); + if (rc == 0) + wait_for_completion(&sclp_request_queue_flushed); + else if (rc != -ENODATA) + goto fail_thaw; + + rc = sclp_deactivate(); + if (rc) + goto fail_thaw; + return 0; + +fail_thaw: + spin_lock_irqsave(&sclp_lock, flags); + sclp_suspend_state = sclp_suspend_state_running; + spin_unlock_irqrestore(&sclp_lock, flags); + sclp_pm_event(SCLP_PM_EVENT_THAW, 1); + return rc; +} + +static int sclp_undo_suspend(enum sclp_pm_event event) +{ + unsigned long flags; + int rc; + + rc = sclp_reactivate(); + if (rc) + return rc; + + spin_lock_irqsave(&sclp_lock, flags); + sclp_suspend_state = sclp_suspend_state_running; + spin_unlock_irqrestore(&sclp_lock, flags); + + sclp_pm_event(event, 0); + return 0; +} + +static int sclp_thaw(struct device *dev) +{ + return sclp_undo_suspend(SCLP_PM_EVENT_THAW); +} + +static int sclp_restore(struct device *dev) +{ + return sclp_undo_suspend(SCLP_PM_EVENT_RESTORE); +} + +static const struct dev_pm_ops sclp_pm_ops = { + .freeze = sclp_freeze, + .thaw = sclp_thaw, + .restore = sclp_restore, +}; + +static ssize_t sclp_show_console_pages(struct device_driver *dev, char *buf) +{ + return sprintf(buf, "%i\n", sclp_console_pages); +} + +static DRIVER_ATTR(con_pages, S_IRUSR, sclp_show_console_pages, NULL); + +static ssize_t sclp_show_con_drop(struct device_driver *dev, char *buf) +{ + return sprintf(buf, "%i\n", sclp_console_drop); +} + +static DRIVER_ATTR(con_drop, S_IRUSR, sclp_show_con_drop, NULL); + +static ssize_t sclp_show_console_full(struct device_driver *dev, char *buf) +{ + return sprintf(buf, "%lu\n", sclp_console_full); +} + +static DRIVER_ATTR(con_full, S_IRUSR, sclp_show_console_full, NULL); + +static struct attribute *sclp_drv_attrs[] = { + &driver_attr_con_pages.attr, + &driver_attr_con_drop.attr, + &driver_attr_con_full.attr, + NULL, +}; +static struct attribute_group sclp_drv_attr_group = { + .attrs = sclp_drv_attrs, +}; +static const struct attribute_group *sclp_drv_attr_groups[] = { + &sclp_drv_attr_group, + NULL, +}; + +static struct platform_driver sclp_pdrv = { + .driver = { + .name = "sclp", + .owner = THIS_MODULE, + .pm = &sclp_pm_ops, + .groups = sclp_drv_attr_groups, + }, +}; + +static struct platform_device *sclp_pdev; + /* Initialize SCLP driver. Return zero if driver is operational, non-zero * otherwise. */ static int sclp_init(void) { unsigned long flags; - int rc; + int rc = 0; spin_lock_irqsave(&sclp_lock, flags); /* Check for previous or running initialization */ - if (sclp_init_state != sclp_init_state_uninitialized) { - spin_unlock_irqrestore(&sclp_lock, flags); - return 0; - } + if (sclp_init_state != sclp_init_state_uninitialized) + goto fail_unlock; sclp_init_state = sclp_init_state_initializing; /* Set up variables */ INIT_LIST_HEAD(&sclp_req_queue); INIT_LIST_HEAD(&sclp_reg_list); list_add(&sclp_state_change_event.list, &sclp_reg_list); init_timer(&sclp_request_timer); + init_timer(&sclp_queue_timer); + sclp_queue_timer.function = sclp_req_queue_timeout; /* Check interface */ spin_unlock_irqrestore(&sclp_lock, flags); rc = sclp_check_interface(); spin_lock_irqsave(&sclp_lock, flags); - if (rc) { - sclp_init_state = sclp_init_state_uninitialized; - spin_unlock_irqrestore(&sclp_lock, flags); - return rc; - } + if (rc) + goto fail_init_state_uninitialized; /* Register reboot handler */ rc = register_reboot_notifier(&sclp_reboot_notifier); - if (rc) { - sclp_init_state = sclp_init_state_uninitialized; - spin_unlock_irqrestore(&sclp_lock, flags); - return rc; - } + if (rc) + goto fail_init_state_uninitialized; /* Register interrupt handler */ - rc = register_early_external_interrupt(0x2401, sclp_interrupt_handler, - &ext_int_info_hwc); - if (rc) { - unregister_reboot_notifier(&sclp_reboot_notifier); - sclp_init_state = sclp_init_state_uninitialized; - spin_unlock_irqrestore(&sclp_lock, flags); - return rc; - } + rc = register_external_irq(EXT_IRQ_SERVICE_SIG, sclp_interrupt_handler); + if (rc) + goto fail_unregister_reboot_notifier; sclp_init_state = sclp_init_state_initialized; spin_unlock_irqrestore(&sclp_lock, flags); /* Enable service-signal external interruption - needs to happen with * IRQs enabled. */ - ctl_set_bit(0, 9); + irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL); sclp_init_mask(1); return 0; + +fail_unregister_reboot_notifier: + unregister_reboot_notifier(&sclp_reboot_notifier); +fail_init_state_uninitialized: + sclp_init_state = sclp_init_state_uninitialized; +fail_unlock: + spin_unlock_irqrestore(&sclp_lock, flags); + return rc; +} + +/* + * SCLP panic notifier: If we are suspended, we thaw SCLP in order to be able + * to print the panic message. + */ +static int sclp_panic_notify(struct notifier_block *self, + unsigned long event, void *data) +{ + if (sclp_suspend_state == sclp_suspend_state_suspended) + sclp_undo_suspend(SCLP_PM_EVENT_THAW); + return NOTIFY_OK; } +static struct notifier_block sclp_on_panic_nb = { + .notifier_call = sclp_panic_notify, + .priority = SCLP_PANIC_PRIO, +}; + static __init int sclp_initcall(void) { + int rc; + + rc = platform_driver_register(&sclp_pdrv); + if (rc) + return rc; + + sclp_pdev = platform_device_register_simple("sclp", -1, NULL, 0); + rc = PTR_ERR_OR_ZERO(sclp_pdev); + if (rc) + goto fail_platform_driver_unregister; + + rc = atomic_notifier_chain_register(&panic_notifier_list, + &sclp_on_panic_nb); + if (rc) + goto fail_platform_device_unregister; + return sclp_init(); + +fail_platform_device_unregister: + platform_device_unregister(sclp_pdev); +fail_platform_driver_unregister: + platform_driver_unregister(&sclp_pdrv); + return rc; } arch_initcall(sclp_initcall); |