| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Heiko Carstens | 2130 | 42.38% | 13 | 26.00% |
| Martin Schwidefsky | 1272 | 25.31% | 11 | 22.00% |
| Michael Holzheu | 813 | 16.18% | 1 | 2.00% |
| Gerald Schaefer | 386 | 7.68% | 2 | 4.00% |
| Peter Oberparleiter | 205 | 4.08% | 7 | 14.00% |
| Claudio Imbrenda | 104 | 2.07% | 3 | 6.00% |
| Kees Cook | 72 | 1.43% | 1 | 2.00% |
| Andrew Morton | 19 | 0.38% | 2 | 4.00% |
| Greg Kroah-Hartman | 7 | 0.14% | 2 | 4.00% |
| Thomas Huth | 6 | 0.12% | 1 | 2.00% |
| Thomas Gleixner | 4 | 0.08% | 1 | 2.00% |
| David Hildenbrand | 3 | 0.06% | 1 | 2.00% |
| David Howells | 1 | 0.02% | 1 | 2.00% |
| Duan Jiong | 1 | 0.02% | 1 | 2.00% |
| Daniel Mack | 1 | 0.02% | 1 | 2.00% |
| Alexey Dobriyan | 1 | 0.02% | 1 | 2.00% |
| Stefan Haberland | 1 | 0.02% | 1 | 2.00% |
| Total | 5026 | 50 |
// SPDX-License-Identifier: GPL-2.0 /* * core function to access sclp interface * * 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> #include <linux/interrupt.h> #include <linux/timer.h> #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/irq.h> #include "sclp.h" #define SCLP_HEADER "sclp: " /* Lock to protect internal data consistency. */ static DEFINE_SPINLOCK(sclp_lock); /* Mask of events that we can send to the sclp interface. */ static sccb_mask_t sclp_receive_mask; /* Mask of events that we can receive from the sclp interface. */ static sccb_mask_t sclp_send_mask; /* List of registered event listeners and senders. */ static struct list_head sclp_reg_list; /* List of queued requests. */ static struct list_head sclp_req_queue; /* Data for read and and init requests. */ static struct sclp_req sclp_read_req; static struct sclp_req sclp_init_req; static void *sclp_read_sccb; static struct init_sccb *sclp_init_sccb; /* 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 = 1; /* 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) sclp_console_drop = drop; 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 a request active at the sclp? */ static volatile enum sclp_running_state_t { sclp_running_state_idle, sclp_running_state_running, sclp_running_state_reset_pending } sclp_running_state = sclp_running_state_idle; /* Internal state: is a read request pending? */ static volatile enum sclp_reading_state_t { sclp_reading_state_idle, sclp_reading_state_reading } sclp_reading_state = sclp_reading_state_idle; /* Internal state: is the driver currently serving requests? */ static volatile enum sclp_activation_state_t { sclp_activation_state_active, sclp_activation_state_deactivating, sclp_activation_state_inactive, sclp_activation_state_activating } sclp_activation_state = sclp_activation_state_active; /* Internal state: is an init mask request pending? */ static volatile enum sclp_mask_state_t { sclp_mask_state_idle, 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 /* Timeout intervals in seconds.*/ #define SCLP_BUSY_INTERVAL 10 #define SCLP_RETRY_INTERVAL 30 static void sclp_request_timeout(bool force_restart); static void sclp_process_queue(void); static void __sclp_make_read_req(void); static int sclp_init_mask(int calculate); static int sclp_init(void); static void __sclp_queue_read_req(void) { if (sclp_reading_state == sclp_reading_state_idle) { sclp_reading_state = sclp_reading_state_reading; __sclp_make_read_req(); /* Add request to head of queue */ list_add(&sclp_read_req.list, &sclp_req_queue); } } /* Set up request retry timer. Called while sclp_lock is locked. */ static inline void __sclp_set_request_timer(unsigned long time, void (*cb)(struct timer_list *)) { del_timer(&sclp_request_timer); sclp_request_timer.function = cb; sclp_request_timer.expires = jiffies + time; add_timer(&sclp_request_timer); } static void sclp_request_timeout_restart(struct timer_list *unused) { sclp_request_timeout(true); } static void sclp_request_timeout_normal(struct timer_list *unused) { sclp_request_timeout(false); } /* Request timeout handler. Restart the request queue. If force_restart, * force restart of running request. */ static void sclp_request_timeout(bool force_restart) { unsigned long flags; spin_lock_irqsave(&sclp_lock, flags); if (force_restart) { if (sclp_running_state == sclp_running_state_running) { /* Break running state and queue NOP read event request * to get a defined interface state. */ __sclp_queue_read_req(); sclp_running_state = sclp_running_state_idle; } } else { __sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ, sclp_request_timeout_normal); } spin_unlock_irqrestore(&sclp_lock, flags); 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(struct timer_list *unused) { 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. */ static int __sclp_start_request(struct sclp_req *req) { int rc; if (sclp_running_state != sclp_running_state_idle) return 0; del_timer(&sclp_request_timer); rc = sclp_service_call(req->command, req->sccb); req->start_count++; if (rc == 0) { /* Successfully started request */ req->status = SCLP_REQ_RUNNING; sclp_running_state = sclp_running_state_running; __sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ, sclp_request_timeout_restart); return 0; } else if (rc == -EBUSY) { /* Try again later */ __sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ, sclp_request_timeout_normal); return 0; } /* Request failed */ req->status = SCLP_REQ_FAILED; return rc; } /* Try to start queued requests. */ static void sclp_process_queue(void) { struct sclp_req *req; int rc; unsigned long flags; spin_lock_irqsave(&sclp_lock, flags); if (sclp_running_state != sclp_running_state_idle) { spin_unlock_irqrestore(&sclp_lock, flags); return; } 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; /* Request failed */ if (req->start_count > 1) { /* Cannot abort already submitted request - could still * be active at the SCLP */ __sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ, sclp_request_timeout_normal); break; } do_post: /* Post-processing for aborted request */ list_del(&req->list); if (req->callback) { spin_unlock_irqrestore(&sclp_lock, flags); req->callback(req, req->callback_data); spin_lock_irqsave(&sclp_lock, flags); } } 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) { unsigned long flags; int rc; spin_lock_irqsave(&sclp_lock, flags); if (!__sclp_can_add_request(req)) { spin_unlock_irqrestore(&sclp_lock, flags); return -EIO; } req->status = SCLP_REQ_QUEUED; 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; } EXPORT_SYMBOL(sclp_add_request); /* Dispatch events found in request buffer to registered listeners. Return 0 * if all events were dispatched, non-zero otherwise. */ static int sclp_dispatch_evbufs(struct sccb_header *sccb) { unsigned long flags; struct evbuf_header *evbuf; struct list_head *l; struct sclp_register *reg; int offset; int rc; spin_lock_irqsave(&sclp_lock, flags); rc = 0; for (offset = sizeof(struct sccb_header); offset < sccb->length; offset += evbuf->length) { evbuf = (struct evbuf_header *) ((addr_t) sccb + offset); /* Check for malformed hardware response */ if (evbuf->length == 0) break; /* Search for event handler */ reg = NULL; list_for_each(l, &sclp_reg_list) { reg = list_entry(l, struct sclp_register, list); if (reg->receive_mask & SCLP_EVTYP_MASK(evbuf->type)) break; else reg = NULL; } if (reg && reg->receiver_fn) { spin_unlock_irqrestore(&sclp_lock, flags); reg->receiver_fn(evbuf); spin_lock_irqsave(&sclp_lock, flags); } else if (reg == NULL) rc = -EOPNOTSUPP; } spin_unlock_irqrestore(&sclp_lock, flags); return rc; } /* Read event data request callback. */ static void sclp_read_cb(struct sclp_req *req, void *data) { unsigned long flags; struct sccb_header *sccb; sccb = (struct sccb_header *) req->sccb; if (req->status == SCLP_REQ_DONE && (sccb->response_code == 0x20 || sccb->response_code == 0x220)) sclp_dispatch_evbufs(sccb); spin_lock_irqsave(&sclp_lock, flags); sclp_reading_state = sclp_reading_state_idle; spin_unlock_irqrestore(&sclp_lock, flags); } /* Prepare read event data request. Called while sclp_lock is locked. */ static void __sclp_make_read_req(void) { struct sccb_header *sccb; sccb = (struct sccb_header *) sclp_read_sccb; clear_page(sccb); memset(&sclp_read_req, 0, sizeof(struct sclp_req)); sclp_read_req.command = SCLP_CMDW_READ_EVENT_DATA; sclp_read_req.status = SCLP_REQ_QUEUED; sclp_read_req.start_count = 0; sclp_read_req.callback = sclp_read_cb; sclp_read_req.sccb = sccb; sccb->length = PAGE_SIZE; sccb->function_code = 0; sccb->control_mask[2] = 0x80; } /* Search request list for request with matching sccb. Return request if found, * NULL otherwise. Called while sclp_lock is locked. */ static inline struct sclp_req * __sclp_find_req(u32 sccb) { struct list_head *l; struct sclp_req *req; list_for_each(l, &sclp_req_queue) { req = list_entry(l, struct sclp_req, list); if (sccb == (u32) (addr_t) req->sccb) return req; } return NULL; } /* 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(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 = param32 & 0xfffffff8; evbuf_pending = param32 & 0x3; if (finished_sccb) { del_timer(&sclp_request_timer); sclp_running_state = sclp_running_state_reset_pending; req = __sclp_find_req(finished_sccb); if (req) { /* Request post-processing */ list_del(&req->list); req->status = SCLP_REQ_DONE; if (req->callback) { spin_unlock(&sclp_lock); req->callback(req, req->callback_data); spin_lock(&sclp_lock); } } sclp_running_state = sclp_running_state_idle; } if (evbuf_pending && sclp_activation_state == sclp_activation_state_active) __sclp_queue_read_req(); spin_unlock(&sclp_lock); sclp_process_queue(); } /* Convert interval in jiffies to TOD ticks. */ static inline u64 sclp_tod_from_jiffies(unsigned long jiffies) { return (u64) (jiffies / HZ) << 32; } /* Wait until a currently running request finished. Note: while this function * is running, no timers are served on the calling CPU. */ void sclp_sync_wait(void) { unsigned long long old_tick; unsigned long flags; unsigned long cr0, cr0_sync; u64 timeout; int irq_context; /* We'll be disabling timer interrupts, so we need a custom timeout * mechanism */ timeout = 0; if (timer_pending(&sclp_request_timer)) { /* Get timeout TOD value */ timeout = get_tod_clock_fast() + sclp_tod_from_jiffies(sclp_request_timer.expires - jiffies); } local_irq_save(flags); /* Prevent bottom half from executing once we force interrupts open */ irq_context = in_interrupt(); if (!irq_context) local_bh_disable(); /* Enable service-signal interruption, disable timer interrupts */ old_tick = local_tick_disable(); trace_hardirqs_on(); __ctl_store(cr0, 0, 0); cr0_sync = cr0 & ~CR0_IRQ_SUBCLASS_MASK; cr0_sync |= 1UL << (63 - 54); __ctl_load(cr0_sync, 0, 0); __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_tod_clock_fast() > timeout && del_timer(&sclp_request_timer)) sclp_request_timer.function(&sclp_request_timer); cpu_relax(); } local_irq_disable(); __ctl_load(cr0, 0, 0); if (!irq_context) _local_bh_enable(); local_tick_enable(old_tick); local_irq_restore(flags); } EXPORT_SYMBOL(sclp_sync_wait); /* Dispatch changes in send and receive mask to registered listeners. */ static void sclp_dispatch_state_change(void) { struct list_head *l; struct sclp_register *reg; unsigned long flags; sccb_mask_t receive_mask; sccb_mask_t send_mask; do { spin_lock_irqsave(&sclp_lock, flags); reg = NULL; list_for_each(l, &sclp_reg_list) { reg = list_entry(l, struct sclp_register, list); receive_mask = reg->send_mask & sclp_receive_mask; send_mask = reg->receive_mask & sclp_send_mask; if (reg->sclp_receive_mask != receive_mask || reg->sclp_send_mask != send_mask) { reg->sclp_receive_mask = receive_mask; reg->sclp_send_mask = send_mask; break; } else reg = NULL; } spin_unlock_irqrestore(&sclp_lock, flags); if (reg && reg->state_change_fn) reg->state_change_fn(reg); } while (reg); } struct sclp_statechangebuf { struct evbuf_header header; u8 validity_sclp_active_facility_mask : 1; u8 validity_sclp_receive_mask : 1; u8 validity_sclp_send_mask : 1; u8 validity_read_data_function_mask : 1; u16 _zeros : 12; u16 mask_length; u64 sclp_active_facility_mask; u8 masks[2 * 1021 + 4]; /* variable length */ /* * u8 sclp_receive_mask[mask_length]; * u8 sclp_send_mask[mask_length]; * u32 read_data_function_mask; */ } __attribute__((packed)); /* State change event callback. Inform listeners of changes. */ static void sclp_state_change_cb(struct evbuf_header *evbuf) { unsigned long flags; struct sclp_statechangebuf *scbuf; BUILD_BUG_ON(sizeof(struct sclp_statechangebuf) > PAGE_SIZE); scbuf = (struct sclp_statechangebuf *) evbuf; spin_lock_irqsave(&sclp_lock, flags); if (scbuf->validity_sclp_receive_mask) sclp_receive_mask = sccb_get_recv_mask(scbuf); if (scbuf->validity_sclp_send_mask) sclp_send_mask = sccb_get_send_mask(scbuf); spin_unlock_irqrestore(&sclp_lock, flags); if (scbuf->validity_sclp_active_facility_mask) sclp.facilities = scbuf->sclp_active_facility_mask; sclp_dispatch_state_change(); } static struct sclp_register sclp_state_change_event = { .receive_mask = EVTYP_STATECHANGE_MASK, .receiver_fn = sclp_state_change_cb }; /* Calculate receive and send mask of currently registered listeners. * Called while sclp_lock is locked. */ static inline void __sclp_get_mask(sccb_mask_t *receive_mask, sccb_mask_t *send_mask) { struct list_head *l; struct sclp_register *t; *receive_mask = 0; *send_mask = 0; list_for_each(l, &sclp_reg_list) { t = list_entry(l, struct sclp_register, list); *receive_mask |= t->receive_mask; *send_mask |= t->send_mask; } } /* Register event listener. Return 0 on success, non-zero otherwise. */ int sclp_register(struct sclp_register *reg) { unsigned long flags; sccb_mask_t receive_mask; sccb_mask_t send_mask; int rc; rc = sclp_init(); if (rc) return rc; spin_lock_irqsave(&sclp_lock, flags); /* Check event mask for collisions */ __sclp_get_mask(&receive_mask, &send_mask); if (reg->receive_mask & receive_mask || reg->send_mask & send_mask) { spin_unlock_irqrestore(&sclp_lock, flags); return -EBUSY; } /* 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); if (rc) { spin_lock_irqsave(&sclp_lock, flags); list_del(®->list); spin_unlock_irqrestore(&sclp_lock, flags); } return rc; } EXPORT_SYMBOL(sclp_register); /* Unregister event listener. */ void sclp_unregister(struct sclp_register *reg) { unsigned long flags; spin_lock_irqsave(&sclp_lock, flags); list_del(®->list); spin_unlock_irqrestore(&sclp_lock, flags); sclp_init_mask(1); } EXPORT_SYMBOL(sclp_unregister); /* Remove event buffers which are marked processed. Return the number of * remaining event buffers. */ int sclp_remove_processed(struct sccb_header *sccb) { struct evbuf_header *evbuf; int unprocessed; u16 remaining; evbuf = (struct evbuf_header *) (sccb + 1); unprocessed = 0; remaining = sccb->length - sizeof(struct sccb_header); while (remaining > 0) { remaining -= evbuf->length; if (evbuf->flags & 0x80) { sccb->length -= evbuf->length; memcpy(evbuf, (void *) ((addr_t) evbuf + evbuf->length), remaining); } else { unprocessed++; evbuf = (struct evbuf_header *) ((addr_t) evbuf + evbuf->length); } } return unprocessed; } EXPORT_SYMBOL(sclp_remove_processed); /* Prepare init mask request. Called while sclp_lock is locked. */ static inline void __sclp_make_init_req(sccb_mask_t receive_mask, sccb_mask_t send_mask) { struct init_sccb *sccb = sclp_init_sccb; clear_page(sccb); memset(&sclp_init_req, 0, sizeof(struct sclp_req)); sclp_init_req.command = SCLP_CMDW_WRITE_EVENT_MASK; sclp_init_req.status = SCLP_REQ_FILLED; sclp_init_req.start_count = 0; sclp_init_req.callback = NULL; sclp_init_req.callback_data = NULL; sclp_init_req.sccb = sccb; sccb->header.length = sizeof(*sccb); if (sclp_mask_compat_mode) sccb->mask_length = SCLP_MASK_SIZE_COMPAT; else sccb->mask_length = sizeof(sccb_mask_t); sccb_set_recv_mask(sccb, receive_mask); sccb_set_send_mask(sccb, send_mask); sccb_set_sclp_recv_mask(sccb, 0); sccb_set_sclp_send_mask(sccb, 0); } /* Start init mask request. If calculate is non-zero, calculate the mask as * requested by registered listeners. Use zero mask otherwise. Return 0 on * success, non-zero otherwise. */ static int sclp_init_mask(int calculate) { unsigned long flags; struct init_sccb *sccb = sclp_init_sccb; sccb_mask_t receive_mask; sccb_mask_t send_mask; int retry; int rc; unsigned long wait; spin_lock_irqsave(&sclp_lock, flags); /* Check if interface is in appropriate state */ if (sclp_mask_state != sclp_mask_state_idle) { spin_unlock_irqrestore(&sclp_lock, flags); return -EBUSY; } if (sclp_activation_state == sclp_activation_state_inactive) { spin_unlock_irqrestore(&sclp_lock, flags); return -EINVAL; } sclp_mask_state = sclp_mask_state_initializing; /* Determine mask */ if (calculate) __sclp_get_mask(&receive_mask, &send_mask); else { receive_mask = 0; send_mask = 0; } rc = -EIO; for (retry = 0; retry <= SCLP_MASK_RETRY; retry++) { /* Prepare request */ __sclp_make_init_req(receive_mask, send_mask); spin_unlock_irqrestore(&sclp_lock, flags); if (sclp_add_request(&sclp_init_req)) { /* Try again later */ wait = jiffies + SCLP_BUSY_INTERVAL * HZ; while (time_before(jiffies, wait)) sclp_sync_wait(); spin_lock_irqsave(&sclp_lock, flags); continue; } while (sclp_init_req.status != SCLP_REQ_DONE && sclp_init_req.status != SCLP_REQ_FAILED) sclp_sync_wait(); spin_lock_irqsave(&sclp_lock, flags); if (sclp_init_req.status == SCLP_REQ_DONE && sccb->header.response_code == 0x20) { /* Successful request */ if (calculate) { sclp_receive_mask = sccb_get_sclp_recv_mask(sccb); sclp_send_mask = sccb_get_sclp_send_mask(sccb); } else { sclp_receive_mask = 0; sclp_send_mask = 0; } spin_unlock_irqrestore(&sclp_lock, flags); sclp_dispatch_state_change(); spin_lock_irqsave(&sclp_lock, flags); rc = 0; break; } } sclp_mask_state = sclp_mask_state_idle; spin_unlock_irqrestore(&sclp_lock, flags); return rc; } /* Deactivate SCLP interface. On success, new requests will be rejected, * events will no longer be dispatched. Return 0 on success, non-zero * otherwise. */ int sclp_deactivate(void) { unsigned long flags; int rc; spin_lock_irqsave(&sclp_lock, flags); /* Deactivate can only be called when active */ if (sclp_activation_state != sclp_activation_state_active) { spin_unlock_irqrestore(&sclp_lock, flags); return -EINVAL; } sclp_activation_state = sclp_activation_state_deactivating; spin_unlock_irqrestore(&sclp_lock, flags); rc = sclp_init_mask(0); spin_lock_irqsave(&sclp_lock, flags); if (rc == 0) sclp_activation_state = sclp_activation_state_inactive; else sclp_activation_state = sclp_activation_state_active; spin_unlock_irqrestore(&sclp_lock, flags); return rc; } EXPORT_SYMBOL(sclp_deactivate); /* Reactivate SCLP interface after sclp_deactivate. On success, new * requests will be accepted, events will be dispatched again. Return 0 on * success, non-zero otherwise. */ int sclp_reactivate(void) { unsigned long flags; int rc; spin_lock_irqsave(&sclp_lock, flags); /* Reactivate can only be called when inactive */ if (sclp_activation_state != sclp_activation_state_inactive) { spin_unlock_irqrestore(&sclp_lock, flags); return -EINVAL; } sclp_activation_state = sclp_activation_state_activating; spin_unlock_irqrestore(&sclp_lock, flags); rc = sclp_init_mask(1); spin_lock_irqsave(&sclp_lock, flags); if (rc == 0) sclp_activation_state = sclp_activation_state_active; else sclp_activation_state = sclp_activation_state_inactive; spin_unlock_irqrestore(&sclp_lock, flags); return rc; } EXPORT_SYMBOL(sclp_reactivate); /* Handler for external interruption used during initialization. Modify * request state to done. */ static void sclp_check_handler(struct ext_code ext_code, unsigned int param32, unsigned long param64) { u32 finished_sccb; inc_irq_stat(IRQEXT_SCP); finished_sccb = param32 & 0xfffffff8; /* Is this the interrupt we are waiting for? */ if (finished_sccb == 0) return; if (finished_sccb != (u32) (addr_t) sclp_init_sccb) panic("sclp: unsolicited interrupt for buffer at 0x%x\n", finished_sccb); spin_lock(&sclp_lock); if (sclp_running_state == sclp_running_state_running) { sclp_init_req.status = SCLP_REQ_DONE; sclp_running_state = sclp_running_state_idle; } spin_unlock(&sclp_lock); } /* Initial init mask request timed out. Modify request state to failed. */ static void sclp_check_timeout(struct timer_list *unused) { unsigned long flags; spin_lock_irqsave(&sclp_lock, flags); if (sclp_running_state == sclp_running_state_running) { sclp_init_req.status = SCLP_REQ_FAILED; sclp_running_state = sclp_running_state_idle; } spin_unlock_irqrestore(&sclp_lock, flags); } /* Perform a check of the SCLP interface. Return zero if the interface is * available and there are no pending requests from a previous instance. * Return non-zero otherwise. */ static int sclp_check_interface(void) { struct init_sccb *sccb; unsigned long flags; int retry; int rc; spin_lock_irqsave(&sclp_lock, flags); /* Prepare init mask command */ rc = register_external_irq(EXT_IRQ_SERVICE_SIG, sclp_check_handler); if (rc) { spin_unlock_irqrestore(&sclp_lock, flags); return rc; } for (retry = 0; retry <= SCLP_INIT_RETRY; retry++) { __sclp_make_init_req(0, 0); sccb = (struct init_sccb *) sclp_init_req.sccb; rc = sclp_service_call(sclp_init_req.command, sccb); if (rc == -EIO) break; sclp_init_req.status = SCLP_REQ_RUNNING; sclp_running_state = sclp_running_state_running; __sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ, sclp_check_timeout); spin_unlock_irqrestore(&sclp_lock, flags); /* Enable service-signal interruption - needs to happen * with IRQs enabled. */ 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. */ irq_subclass_unregister(IRQ_SUBCLASS_SERVICE_SIGNAL); spin_lock_irqsave(&sclp_lock, flags); del_timer(&sclp_request_timer); rc = -EBUSY; if (sclp_init_req.status == SCLP_REQ_DONE) { if (sccb->header.response_code == 0x20) { rc = 0; break; } else if (sccb->header.response_code == 0x74f0) { if (!sclp_mask_compat_mode) { sclp_mask_compat_mode = true; retry = 0; } } } } unregister_external_irq(EXT_IRQ_SERVICE_SIG, sclp_check_handler); spin_unlock_irqrestore(&sclp_lock, flags); return rc; } /* Reboot event handler. Reset send and receive mask to prevent pending SCLP * events from interfering with rebooted system. */ static int sclp_reboot_event(struct notifier_block *this, unsigned long event, void *ptr) { sclp_deactivate(); return NOTIFY_DONE; } 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 con_pages_show(struct device_driver *dev, char *buf) { return sprintf(buf, "%i\n", sclp_console_pages); } static DRIVER_ATTR_RO(con_pages); static ssize_t con_drop_show(struct device_driver *dev, char *buf) { return sprintf(buf, "%i\n", sclp_console_drop); } static DRIVER_ATTR_RO(con_drop); static ssize_t con_full_show(struct device_driver *dev, char *buf) { return sprintf(buf, "%lu\n", sclp_console_full); } static DRIVER_ATTR_RO(con_full); 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", .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 = 0; spin_lock_irqsave(&sclp_lock, flags); /* Check for previous or running initialization */ if (sclp_init_state != sclp_init_state_uninitialized) goto fail_unlock; sclp_init_state = sclp_init_state_initializing; sclp_read_sccb = (void *) __get_free_page(GFP_ATOMIC | GFP_DMA); sclp_init_sccb = (void *) __get_free_page(GFP_ATOMIC | GFP_DMA); BUG_ON(!sclp_read_sccb || !sclp_init_sccb); /* 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); timer_setup(&sclp_request_timer, NULL, 0); timer_setup(&sclp_queue_timer, sclp_req_queue_timeout, 0); /* Check interface */ spin_unlock_irqrestore(&sclp_lock, flags); rc = sclp_check_interface(); spin_lock_irqsave(&sclp_lock, flags); if (rc) goto fail_init_state_uninitialized; /* Register reboot handler */ rc = register_reboot_notifier(&sclp_reboot_notifier); if (rc) goto fail_init_state_uninitialized; /* Register interrupt handler */ 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. */ 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; free_page((unsigned long) sclp_read_sccb); free_page((unsigned long) sclp_init_sccb); 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);
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