litmus-rt.git - The LITMUS^RT kernel.

diff options

Diffstat (limited to 'net/sunrpc/xprt.c')

-rw-r--r--

1 files changed, 46 insertions, 14 deletions

  *  -   Next, the caller puts together the RPC message, stuffs it into
  *      the request struct, and calls xprt_transmit().
  *  -   xprt_transmit sends the message and installs the caller on the
- *      transport's wait list. At the same time, it installs a timer that
+ *      transport's wait list. At the same time, if a reply is expected,
- *      is run after the packet's timeout has expired.
+ *      it installs a timer that is run after the packet's timeout has
+ *      expired.
  *  -   When a packet arrives, the data_ready handler walks the list of
  *      pending requests for that transport. If a matching XID is found, the
  *      caller is woken up, and the timer removed.
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/metrics.h>
+#include "sunrpc.h"
 /*
  * Local variables
  */
  */
 int xprt_reserve_xprt(struct rpc_task *task)
 {
-        struct rpc_xprt *xprt = task->tk_xprt;
         struct rpc_rqst *req = task->tk_rqstp;
+        struct rpc_xprt *xprt = req->rq_xprt;
         if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) {
                 if (task == xprt->snd_task)
         list_del_init(&req->rq_list);
         req->rq_private_buf.len = copied;
-        /* Ensure all writes are done before we update req->rq_received */
+        /* Ensure all writes are done before we update */
+        /* req->rq_reply_bytes_recvd */
         smp_wmb();
-        req->rq_received = copied;
+        req->rq_reply_bytes_recvd = copied;
         rpc_wake_up_queued_task(&xprt->pending, task);
 }
 EXPORT_SYMBOL_GPL(xprt_complete_rqst);
         dprintk("RPC: %5u xprt_timer\n", task->tk_pid);
         spin_lock_bh(&xprt->transport_lock);
-        if (!req->rq_received) {
+        if (!req->rq_reply_bytes_recvd) {
                 if (xprt->ops->timer)
                         xprt->ops->timer(task);
         } else
         dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid);
         spin_lock_bh(&xprt->transport_lock);
-        if (req->rq_received && !req->rq_bytes_sent) {
+        if (req->rq_reply_bytes_recvd && !req->rq_bytes_sent) {
-                err = req->rq_received;
+                err = req->rq_reply_bytes_recvd;
                 goto out_unlock;
         }
         if (!xprt->ops->reserve_xprt(task))
 void xprt_end_transmit(struct rpc_task *task)
 {
-        xprt_release_write(task->tk_xprt, task);
+        xprt_release_write(task->tk_rqstp->rq_xprt, task);
 }
 /**
         dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen);
-        if (!req->rq_received) {
+        if (!req->rq_reply_bytes_recvd) {
-                if (list_empty(&req->rq_list)) {
+                if (list_empty(&req->rq_list) && rpc_reply_expected(task)) {
+                        /*
+                         * Add to the list only if we're expecting a reply
+                         */
                         spin_lock_bh(&xprt->transport_lock);
                         /* Update the softirq receive buffer */
                         memcpy(&req->rq_private_buf, &req->rq_rcv_buf,
         /* Don't race with disconnect */
         if (!xprt_connected(xprt))
                 task->tk_status = -ENOTCONN;
-        else if (!req->rq_received)
+        else if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) {
+                /*
+                 * Sleep on the pending queue since
+                 * we're expecting a reply.
+                 */
                 rpc_sleep_on(&xprt->pending, task, xprt_timer);
+        }
         spin_unlock_bh(&xprt->transport_lock);
 }
  */
 void xprt_release(struct rpc_task *task)
 {
-        struct rpc_xprt *xprt = task->tk_xprt;
+        struct rpc_xprt *xprt;
         struct rpc_rqst *req;
+        int is_bc_request;
         if (!(req = task->tk_rqstp))
                 return;
+        /* Preallocated backchannel request? */
+        is_bc_request = bc_prealloc(req);
+        xprt = req->rq_xprt;
         rpc_count_iostats(task);
         spin_lock_bh(&xprt->transport_lock);
         xprt->ops->release_xprt(xprt, task);
                 mod_timer(&xprt->timer,
                                 xprt->last_used + xprt->idle_timeout);
         spin_unlock_bh(&xprt->transport_lock);
-        xprt->ops->buf_free(req->rq_buffer);
+        if (!bc_prealloc(req))
+                xprt->ops->buf_free(req->rq_buffer);
         task->tk_rqstp = NULL;
         if (req->rq_release_snd_buf)
                 req->rq_release_snd_buf(req);
+        /*
+         * Early exit if this is a backchannel preallocated request.
+         * There is no need to have it added to the RPC slot list.
+         */
+        if (is_bc_request)
+                return;
         memset(req, 0, sizeof(*req));   /* mark unused */
         dprintk("RPC: %5u release request %p\n", task->tk_pid, req);
         INIT_LIST_HEAD(&xprt->free);
         INIT_LIST_HEAD(&xprt->recv);
+#if defined(CONFIG_NFS_V4_1)
+        spin_lock_init(&xprt->bc_pa_lock);
+        INIT_LIST_HEAD(&xprt->bc_pa_list);
+#endif /* CONFIG_NFS_V4_1 */
         INIT_WORK(&xprt->task_cleanup, xprt_autoclose);
         setup_timer(&xprt->timer, xprt_init_autodisconnect,
                         (unsigned long)xprt);

/* * arch/s390/kernel/time.c * Time of day based timer functions. * * S390 version * Copyright IBM Corp. 1999, 2008 * Author(s): Hartmut Penner (hp@de.ibm.com), * Martin Schwidefsky (schwidefsky@de.ibm.com), * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com) * * Derived from "arch/i386/kernel/time.c" * Copyright (C) 1991, 1992, 1995 Linus Torvalds */ #define KMSG_COMPONENT "time" #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt #include <linux/errno.h> #include <linux/module.h> #include <linux/sched.h> #include <linux/kernel.h> #include <linux/param.h> #include <linux/string.h> #include <linux/mm.h> #include <linux/interrupt.h> #include <linux/cpu.h> #include <linux/stop_machine.h> #include <linux/time.h> #include <linux/sysdev.h> #include <linux/delay.h> #include <linux/init.h> #include <linux/smp.h> #include <linux/types.h> #include <linux/profile.h> #include <linux/timex.h> #include <linux/notifier.h> #include <linux/clocksource.h> #include <linux/clockchips.h> #include <asm/uaccess.h> #include <asm/delay.h> #include <asm/s390_ext.h> #include <asm/div64.h> #include <asm/vdso.h> #include <asm/irq.h> #include <asm/irq_regs.h> #include <asm/timer.h> #include <asm/etr.h> #include <asm/cio.h> /* change this if you have some constant time drift */ #define USECS_PER_JIFFY ((unsigned long) 1000000/HZ) #define CLK_TICKS_PER_JIFFY ((unsigned long) USECS_PER_JIFFY << 12) u64 sched_clock_base_cc = -1; /* Force to data section. */ EXPORT_SYMBOL_GPL(sched_clock_base_cc); static DEFINE_PER_CPU(struct clock_event_device, comparators); /* * Scheduler clock - returns current time in nanosec units. */ unsigned long long notrace sched_clock(void) { return (get_clock_monotonic() * 125) >> 9; } /* * Monotonic_clock - returns # of nanoseconds passed since time_init() */ unsigned long long monotonic_clock(void) { return sched_clock(); } EXPORT_SYMBOL(monotonic_clock); void tod_to_timeval(__u64 todval, struct timespec *xt) { unsigned long long sec; sec = todval >> 12; do_div(sec, 1000000); xt->tv_sec = sec; todval -= (sec * 1000000) << 12; xt->tv_nsec = ((todval * 1000) >> 12); } EXPORT_SYMBOL(tod_to_timeval); void clock_comparator_work(void) { struct clock_event_device *cd; S390_lowcore.clock_comparator = -1ULL; set_clock_comparator(S390_lowcore.clock_comparator); cd = &__get_cpu_var(comparators); cd->event_handler(cd); } /* * Fixup the clock comparator. */ static void fixup_clock_comparator(unsigned long long delta) { /* If nobody is waiting there's nothing to fix. */ if (S390_lowcore.clock_comparator == -1ULL) return; S390_lowcore.clock_comparator += delta; set_clock_comparator(S390_lowcore.clock_comparator); } static int s390_next_event(unsigned long delta, struct clock_event_device *evt) { S390_lowcore.clock_comparator = get_clock() + delta; set_clock_comparator(S390_lowcore.clock_comparator); return 0; } static void s390_set_mode(enum clock_event_mode mode, struct clock_event_device *evt) { } /* * Set up lowcore and control register of the current cpu to * enable TOD clock and clock comparator interrupts. */ void init_cpu_timer(void) { struct clock_event_device *cd; int cpu; S390_lowcore.clock_comparator = -1ULL; set_clock_comparator(S390_lowcore.clock_comparator); cpu = smp_processor_id(); cd = &per_cpu(comparators, cpu); cd->name = "comparator"; cd->features = CLOCK_EVT_FEAT_ONESHOT; cd->mult = 16777; cd->shift = 12; cd->min_delta_ns = 1; cd->max_delta_ns = LONG_MAX; cd->rating = 400; cd->cpumask = cpumask_of(cpu); cd->set_next_event = s390_next_event; cd->set_mode = s390_set_mode; clockevents_register_device(cd); /* Enable clock comparator timer interrupt. */ __ctl_set_bit(0,11); /* Always allow the timing alert external interrupt. */ __ctl_set_bit(0, 4); } static void clock_comparator_interrupt(__u16 code) { if (S390_lowcore.clock_comparator == -1ULL) set_clock_comparator(S390_lowcore.clock_comparator); } static void etr_timing_alert(struct etr_irq_parm *); static void stp_timing_alert(struct stp_irq_parm *); static void timing_alert_interrupt(__u16 code) { if (S390_lowcore.ext_params & 0x00c40000) etr_timing_alert((struct etr_irq_parm *) &S390_lowcore.ext_params); if (S390_lowcore.ext_params & 0x00038000) stp_timing_alert((struct stp_irq_parm *) &S390_lowcore.ext_params); } static void etr_reset(void); static void stp_reset(void); void read_persistent_clock(struct timespec *ts) { tod_to_timeval(get_clock() - TOD_UNIX_EPOCH, ts); } void read_boot_clock(struct timespec *ts) { tod_to_timeval(sched_clock_base_cc - TOD_UNIX_EPOCH, ts); } static cycle_t read_tod_clock(struct clocksource *cs) { return get_clock(); } static struct clocksource clocksource_tod = { .name = "tod", .rating = 400, .read = read_tod_clock, .mask = -1ULL, .mult = 1000, .shift = 12, .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; struct clocksource * __init clocksource_default_clock(void) { return &clocksource_tod; } void update_vsyscall(struct timespec *wall_time, struct clocksource *clock, u32 mult) { if (clock != &clocksource_tod) return; /* Make userspace gettimeofday spin until we're done. */ ++vdso_data->tb_update_count; smp_wmb(); vdso_data->xtime_tod_stamp = clock->cycle_last; vdso_data->xtime_clock_sec = wall_time->tv_sec; vdso_data->xtime_clock_nsec = wall_time->tv_nsec; vdso_data->wtom_clock_sec = wall_to_monotonic.tv_sec; vdso_data->wtom_clock_nsec = wall_to_monotonic.tv_nsec; smp_wmb(); ++vdso_data->tb_update_count; } extern struct timezone sys_tz; void update_vsyscall_tz(void) { /* Make userspace gettimeofday spin until we're done. */ ++vdso_data->tb_update_count; smp_wmb(); vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; vdso_data->tz_dsttime = sys_tz.tz_dsttime; smp_wmb(); ++vdso_data->tb_update_count; } /* * Initialize the TOD clock and the CPU timer of * the boot cpu. */ void __init time_init(void) { /* Reset time synchronization interfaces. */ etr_reset(); stp_reset(); /* request the clock comparator external interrupt */ if (register_external_interrupt(0x1004, clock_comparator_interrupt)) panic("Couldn't request external interrupt 0x1004"); /* request the timing alert external interrupt */ if (register_external_interrupt(0x1406, timing_alert_interrupt)) panic("Couldn't request external interrupt 0x1406"); if (clocksource_register(&clocksource_tod) != 0) panic("Could not register TOD clock source"); /* Enable TOD clock interrupts on the boot cpu. */ init_cpu_timer(); /* Enable cpu timer interrupts on the boot cpu. */ vtime_init(); } /* * The time is "clock". old is what we think the time is. * Adjust the value by a multiple of jiffies and add the delta to ntp. * "delay" is an approximation how long the synchronization took. If * the time correction is positive, then "delay" is subtracted from * the time difference and only the remaining part is passed to ntp. */ static unsigned long long adjust_time(unsigned long long old, unsigned long long clock, unsigned long long delay) { unsigned long long delta, ticks; struct timex adjust; if (clock > old) { /* It is later than we thought. */ delta = ticks = clock - old; delta = ticks = (delta < delay) ? 0 : delta - delay; delta -= do_div(ticks, CLK_TICKS_PER_JIFFY); adjust.offset = ticks * (1000000 / HZ); } else { /* It is earlier than we thought. */ delta = ticks = old - clock; delta -= do_div(ticks, CLK_TICKS_PER_JIFFY); delta = -delta; adjust.offset = -ticks * (1000000 / HZ); } sched_clock_base_cc += delta; if (adjust.offset != 0) { pr_notice("The ETR interface has adjusted the clock " "by %li microseconds\n", adjust.offset); adjust.modes = ADJ_OFFSET_SINGLESHOT; do_adjtimex(&adjust); } return delta; } static DEFINE_PER_CPU(atomic_t, clock_sync_word); static DEFINE_MUTEX(clock_sync_mutex); static unsigned long clock_sync_flags; #define CLOCK_SYNC_HAS_ETR 0 #define CLOCK_SYNC_HAS_STP 1 #define CLOCK_SYNC_ETR 2 #define CLOCK_SYNC_STP 3 /* * The synchronous get_clock function. It will write the current clock * value to the clock pointer and return 0 if the clock is in sync with * the external time source. If the clock mode is local it will return * -ENOSYS and -EAGAIN if the clock is not in sync with the external * reference. */ int get_sync_clock(unsigned long long *clock) { atomic_t *sw_ptr; unsigned int sw0, sw1; sw_ptr = &get_cpu_var(clock_sync_word); sw0 = atomic_read(sw_ptr); *clock = get_clock(); sw1 = atomic_read(sw_ptr); put_cpu_var(clock_sync_word); if (sw0 == sw1 && (sw0 & 0x80000000U)) /* Success: time is in sync. */ return 0; if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags) && !test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) return -ENOSYS; if (!test_bit(CLOCK_SYNC_ETR, &clock_sync_flags) && !test_bit(CLOCK_SYNC_STP, &clock_sync_flags)) return -EACCES; return -EAGAIN; } EXPORT_SYMBOL(get_sync_clock); /* * Make get_sync_clock return -EAGAIN. */ static void disable_sync_clock(void *dummy) { atomic_t *sw_ptr = &__get_cpu_var(clock_sync_word); /* * Clear the in-sync bit 2^31. All get_sync_clock calls will * fail until the sync bit is turned back on. In addition * increase the "sequence" counter to avoid the race of an * etr event and the complete recovery against get_sync_clock. */ atomic_clear_mask(0x80000000, sw_ptr); atomic_inc(sw_ptr); } /* * Make get_sync_clock return 0 again. * Needs to be called from a context disabled for preemption. */ static void enable_sync_clock(void) { atomic_t *sw_ptr = &__get_cpu_var(clock_sync_word); atomic_set_mask(0x80000000, sw_ptr); } /* * Function to check if the clock is in sync. */ static inline int check_sync_clock(void) { atomic_t *sw_ptr; int rc; sw_ptr = &get_cpu_var(clock_sync_word); rc = (atomic_read(sw_ptr) & 0x80000000U) != 0; put_cpu_var(clock_sync_word); return rc; } /* Single threaded workqueue used for etr and stp sync events */ static struct workqueue_struct *time_sync_wq; static void __init time_init_wq(void) { if (time_sync_wq) return; time_sync_wq = create_singlethread_workqueue("timesync"); stop_machine_create(); } /* * External Time Reference (ETR) code. */ static int etr_port0_online; static int etr_port1_online; static int etr_steai_available; static int __init early_parse_etr(char *p) { if (strncmp(p, "off", 3) == 0) etr_port0_online = etr_port1_online = 0; else if (strncmp(p, "port0", 5) == 0) etr_port0_online = 1; else if (strncmp(p, "port1", 5) == 0) etr_port1_online = 1; else if (strncmp(p, "on", 2) == 0) etr_port0_online = etr_port1_online = 1; return 0; } early_param("etr", early_parse_etr); enum etr_event { ETR_EVENT_PORT0_CHANGE, ETR_EVENT_PORT1_CHANGE, ETR_EVENT_PORT_ALERT, ETR_EVENT_SYNC_CHECK, ETR_EVENT_SWITCH_LOCAL, ETR_EVENT_UPDATE, }; /* * Valid bit combinations of the eacr register are (x = don't care): * e0 e1 dp p0 p1 ea es sl * 0 0 x 0 0 0 0 0 initial, disabled state * 0 0 x 0 1 1 0 0 port 1 online * 0 0 x 1 0 1 0 0 port 0 online * 0 0 x 1 1 1 0 0 both ports online * 0 1 x 0 1 1 0 0 port 1 online and usable, ETR or PPS mode * 0 1 x 0 1 1 0 1 port 1 online, usable and ETR mode * 0 1 x 0 1 1 1 0 port 1 online, usable, PPS mode, in-sync * 0 1 x 0 1 1 1 1 port 1 online, usable, ETR mode, in-sync * 0 1 x 1 1 1 0 0 both ports online, port 1 usable * 0 1 x 1 1 1 1 0 both ports online, port 1 usable, PPS mode, in-sync * 0 1 x 1 1 1 1 1 both ports online, port 1 usable, ETR mode, in-sync * 1 0 x 1 0 1 0 0 port 0 online and usable, ETR or PPS mode * 1 0 x 1 0 1 0 1 port 0 online, usable and ETR mode * 1 0 x 1 0 1 1 0 port 0 online, usable, PPS mode, in-sync * 1 0 x 1 0 1 1 1 port 0 online, usable, ETR mode, in-sync * 1 0 x 1 1 1 0 0 both ports online, port 0 usable * 1 0 x 1 1 1 1 0 both ports online, port 0 usable, PPS mode, in-sync * 1 0 x 1 1 1 1 1 both ports online, port 0 usable, ETR mode, in-sync * 1 1 x 1 1 1 1 0 both ports online & usable, ETR, in-sync * 1 1 x 1 1 1 1 1 both ports online & usable, ETR, in-sync */ static struct etr_eacr etr_eacr; static u64 etr_tolec; /* time of last eacr update */ static struct etr_aib etr_port0; static int etr_port0_uptodate; static struct etr_aib etr_port1; static int etr_port1_uptodate; static unsigned long etr_events; static struct timer_list etr_timer; static void etr_timeout(unsigned long dummy); static void etr_work_fn(struct work_struct *work); static DEFINE_MUTEX(etr_work_mutex); static DECLARE_WORK(etr_work, etr_work_fn); /* * Reset ETR attachment. */ static void etr_reset(void) { etr_eacr = (struct etr_eacr) { .e0 = 0, .e1 = 0, ._pad0 = 4, .dp = 0, .p0 = 0, .p1 = 0, ._pad1 = 0, .ea = 0, .es = 0, .sl = 0 }; if (etr_setr(&etr_eacr) == 0) { etr_tolec = get_clock(); set_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags); if (etr_port0_online && etr_port1_online) set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); } else if (etr_port0_online || etr_port1_online) { pr_warning("The real or virtual hardware system does " "not provide an ETR interface\n"); etr_port0_online = etr_port1_online = 0; } } static int __init etr_init(void) { struct etr_aib aib; if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags)) return 0; time_init_wq(); /* Check if this machine has the steai instruction. */ if (etr_steai(&aib, ETR_STEAI_STEPPING_PORT) == 0) etr_steai_available = 1; setup_timer(&etr_timer, etr_timeout, 0UL); if (etr_port0_online) { set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); queue_work(time_sync_wq, &etr_work); } if (etr_port1_online) { set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); queue_work(time_sync_wq, &etr_work); } return 0; } arch_initcall(etr_init); /* * Two sorts of ETR machine checks. The architecture reads: * "When a machine-check niterruption occurs and if a switch-to-local or * ETR-sync-check interrupt request is pending but disabled, this pending * disabled interruption request is indicated and is cleared". * Which means that we can get etr_switch_to_local events from the machine * check handler although the interruption condition is disabled. Lovely.. */ /* * Switch to local machine check. This is called when the last usable * ETR port goes inactive. After switch to local the clock is not in sync. */ void etr_switch_to_local(void) { if (!etr_eacr.sl) return; disable_sync_clock(NULL); set_bit(ETR_EVENT_SWITCH_LOCAL, &etr_events); queue_work(time_sync_wq, &etr_work); } /* * ETR sync check machine check. This is called when the ETR OTE and the * local clock OTE are farther apart than the ETR sync check tolerance. * After a ETR sync check the clock is not in sync. The machine check * is broadcasted to all cpus at the same time. */ void etr_sync_check(void) { if (!etr_eacr.es) return; disable_sync_clock(NULL); set_bit(ETR_EVENT_SYNC_CHECK, &etr_events); queue_work(time_sync_wq, &etr_work); } /* * ETR timing alert. There are two causes: * 1) port state change, check the usability of the port * 2) port alert, one of the ETR-data-validity bits (v1-v2 bits of the * sldr-status word) or ETR-data word 1 (edf1) or ETR-data word 3 (edf3) * or ETR-data word 4 (edf4) has changed. */ static void etr_timing_alert(struct etr_irq_parm *intparm) { if (intparm->pc0) /* ETR port 0 state change. */ set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); if (intparm->pc1) /* ETR port 1 state change. */ set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); if (intparm->eai) /* * ETR port alert on either port 0, 1 or both. * Both ports are not up-to-date now. */ set_bit(ETR_EVENT_PORT_ALERT, &etr_events); queue_work(time_sync_wq, &etr_work); } static void etr_timeout(unsigned long dummy) { set_bit(ETR_EVENT_UPDATE, &etr_events); queue_work(time_sync_wq, &etr_work); } /* * Check if the etr mode is pss. */ static inline int etr_mode_is_pps(struct etr_eacr eacr) { return eacr.es && !eacr.sl; } /* * Check if the etr mode is etr. */ static inline int etr_mode_is_etr(struct etr_eacr eacr) { return eacr.es && eacr.sl; } /* * Check if the port can be used for TOD synchronization. * For PPS mode the port has to receive OTEs. For ETR mode * the port has to receive OTEs, the ETR stepping bit has to * be zero and the validity bits for data frame 1, 2, and 3 * have to be 1. */ static int etr_port_valid(struct etr_aib *aib, int port) { unsigned int psc; /* Check that this port is receiving OTEs. */ if (aib->tsp == 0) return 0; psc = port ? aib->esw.psc1 : aib->esw.psc0; if (psc == etr_lpsc_pps_mode) return 1; if (psc == etr_lpsc_operational_step) return !aib->esw.y && aib->slsw.v1 && aib->slsw.v2 && aib->slsw.v3; return 0; } /* * Check if two ports are on the same network. */ static int etr_compare_network(struct etr_aib *aib1, struct etr_aib *aib2) { // FIXME: any other fields we have to compare? return aib1->edf1.net_id == aib2->edf1.net_id; } /* * Wrapper for etr_stei that converts physical port states * to logical port states to be consistent with the output * of stetr (see etr_psc vs. etr_lpsc). */ static void etr_steai_cv(struct etr_aib *aib, unsigned int func) { BUG_ON(etr_steai(aib, func) != 0); /* Convert port state to logical port state. */ if (aib->esw.psc0 == 1) aib->esw.psc0 = 2; else if (aib->esw.psc0 == 0 && aib->esw.p == 0) aib->esw.psc0 = 1; if (aib->esw.psc1 == 1) aib->esw.psc1 = 2; else if (aib->esw.psc1 == 0 && aib->esw.p == 1) aib->esw.psc1 = 1; } /* * Check if the aib a2 is still connected to the same attachment as * aib a1, the etv values differ by one and a2 is valid. */ static int etr_aib_follows(struct etr_aib *a1, struct etr_aib *a2, int p) { int state_a1, state_a2; /* Paranoia check: e0/e1 should better be the same. */ if (a1->esw.eacr.e0 != a2->esw.eacr.e0 || a1->esw.eacr.e1 != a2->esw.eacr.e1) return 0; /* Still connected to the same etr ? */ state_a1 = p ? a1->esw.psc1 : a1->esw.psc0; state_a2 = p ? a2->esw.psc1 : a2->esw.psc0; if (state_a1 == etr_lpsc_operational_step) { if (state_a2 != etr_lpsc_operational_step || a1->edf1.net_id != a2->edf1.net_id || a1->edf1.etr_id != a2->edf1.etr_id || a1->edf1.etr_pn != a2->edf1.etr_pn) return 0; } else if (state_a2 != etr_lpsc_pps_mode) return 0; /* The ETV value of a2 needs to be ETV of a1 + 1. */ if (a1->edf2.etv + 1 != a2->edf2.etv) return 0; if (!etr_port_valid(a2, p)) return 0; return 1; } struct clock_sync_data { atomic_t cpus; int in_sync; unsigned long long fixup_cc; int etr_port; struct etr_aib *etr_aib; }; static void clock_sync_cpu(struct clock_sync_data *sync) { atomic_dec(&sync->cpus); enable_sync_clock(); /* * This looks like a busy wait loop but it isn't. etr_sync_cpus * is called on all other cpus while the TOD clocks is stopped. * __udelay will stop the cpu on an enabled wait psw until the * TOD is running again. */ while (sync->in_sync == 0) { __udelay(1); /* * A different cpu changes *in_sync. Therefore use * barrier() to force memory access. */ barrier(); } if (sync->in_sync != 1) /* Didn't work. Clear per-cpu in sync bit again. */ disable_sync_clock(NULL); /* * This round of TOD syncing is done. Set the clock comparator * to the next tick and let the processor continue. */ fixup_clock_comparator(sync->fixup_cc); } /* * Sync the TOD clock using the port refered to by aibp. This port * has to be enabled and the other port has to be disabled. The * last eacr update has to be more than 1.6 seconds in the past. */ static int etr_sync_clock(void *data) { static int first; unsigned long long clock, old_clock, delay, delta; struct clock_sync_data *etr_sync; struct etr_aib *sync_port, *aib; int port; int rc; etr_sync = data; if (xchg(&first, 1) == 1) { /* Slave */ clock_sync_cpu(etr_sync); return 0; } /* Wait until all other cpus entered the sync function. */ while (atomic_read(&etr_sync->cpus) != 0) cpu_relax(); port = etr_sync->etr_port; aib = etr_sync->etr_aib; sync_port = (port == 0) ? &etr_port0 : &etr_port1; enable_sync_clock(); /* Set clock to next OTE. */ __ctl_set_bit(14, 21); __ctl_set_bit(0, 29); clock = ((unsigned long long) (aib->edf2.etv + 1)) << 32; old_clock = get_clock(); if (set_clock(clock) == 0) { __udelay(1); /* Wait for the clock to start. */ __ctl_clear_bit(0, 29); __ctl_clear_bit(14, 21); etr_stetr(aib); /* Adjust Linux timing variables. */ delay = (unsigned long long) (aib->edf2.etv - sync_port->edf2.etv) << 32; delta = adjust_time(old_clock, clock, delay); etr_sync->fixup_cc = delta; fixup_clock_comparator(delta); /* Verify that the clock is properly set. */ if (!etr_aib_follows(sync_port, aib, port)) { /* Didn't work. */ disable_sync_clock(NULL); etr_sync->in_sync = -EAGAIN; rc = -EAGAIN; } else { etr_sync->in_sync = 1; rc = 0; } } else { /* Could not set the clock ?!? */ __ctl_clear_bit(0, 29); __ctl_clear_bit(14, 21); disable_sync_clock(NULL); etr_sync->in_sync = -EAGAIN; rc = -EAGAIN; } xchg(&first, 0); return rc; } static int etr_sync_clock_stop(struct etr_aib *aib, int port) { struct clock_sync_data etr_sync; struct etr_aib *sync_port; int follows; int rc; /* Check if the current aib is adjacent to the sync port aib. */ sync_port = (port == 0) ? &etr_port0 : &etr_port1; follows = etr_aib_follows(sync_port, aib, port); memcpy(sync_port, aib, sizeof(*aib)); if (!follows) return -EAGAIN; memset(&etr_sync, 0, sizeof(etr_sync)); etr_sync.etr_aib = aib; etr_sync.etr_port = port; get_online_cpus(); atomic_set(&etr_sync.cpus, num_online_cpus() - 1); rc = stop_machine(etr_sync_clock, &etr_sync, &cpu_online_map); put_online_cpus(); return rc; } /* * Handle the immediate effects of the different events. * The port change event is used for online/offline changes. */ static struct etr_eacr etr_handle_events(struct etr_eacr eacr) { if (test_and_clear_bit(ETR_EVENT_SYNC_CHECK, &etr_events)) eacr.es = 0; if (test_and_clear_bit(ETR_EVENT_SWITCH_LOCAL, &etr_events)) eacr.es = eacr.sl = 0; if (test_and_clear_bit(ETR_EVENT_PORT_ALERT, &etr_events)) etr_port0_uptodate = etr_port1_uptodate = 0; if (test_and_clear_bit(ETR_EVENT_PORT0_CHANGE, &etr_events)) { if (eacr.e0) /* * Port change of an enabled port. We have to * assume that this can have caused an stepping * port switch. */ etr_tolec = get_clock(); eacr.p0 = etr_port0_online; if (!eacr.p0) eacr.e0 = 0; etr_port0_uptodate = 0; } if (test_and_clear_bit(ETR_EVENT_PORT1_CHANGE, &etr_events)) { if (eacr.e1) /* * Port change of an enabled port. We have to * assume that this can have caused an stepping * port switch. */ etr_tolec = get_clock(); eacr.p1 = etr_port1_online; if (!eacr.p1) eacr.e1 = 0; etr_port1_uptodate = 0; } clear_bit(ETR_EVENT_UPDATE, &etr_events); return eacr; } /* * Set up a timer that expires after the etr_tolec + 1.6 seconds if * one of the ports needs an update. */ static void etr_set_tolec_timeout(unsigned long long now) { unsigned long micros; if ((!etr_eacr.p0 || etr_port0_uptodate) && (!etr_eacr.p1 || etr_port1_uptodate)) return; micros = (now > etr_tolec) ? ((now - etr_tolec) >> 12) : 0; micros = (micros > 1600000) ? 0 : 1600000 - micros; mod_timer(&etr_timer, jiffies + (micros * HZ) / 1000000 + 1); } /* * Set up a time that expires after 1/2 second. */ static void etr_set_sync_timeout(void) { mod_timer(&etr_timer, jiffies + HZ/2); } /* * Update the aib information for one or both ports. */ static struct etr_eacr etr_handle_update(struct etr_aib *aib, struct etr_eacr eacr) { /* With both ports disabled the aib information is useless. */ if (!eacr.e0 && !eacr.e1) return eacr; /* Update port0 or port1 with aib stored in etr_work_fn. */ if (aib->esw.q == 0) { /* Information for port 0 stored. */ if (eacr.p0 && !etr_port0_uptodate) { etr_port0 = *aib; if (etr_port0_online) etr_port0_uptodate = 1; } } else { /* Information for port 1 stored. */ if (eacr.p1 && !etr_port1_uptodate) { etr_port1 = *aib; if (etr_port0_online) etr_port1_uptodate = 1; } } /* * Do not try to get the alternate port aib if the clock * is not in sync yet. */ if (!check_sync_clock()) return eacr; /* * If steai is available we can get the information about * the other port immediately. If only stetr is available the * data-port bit toggle has to be used. */ if (etr_steai_available) { if (eacr.p0 && !etr_port0_uptodate) { etr_steai_cv(&etr_port0, ETR_STEAI_PORT_0); etr_port0_uptodate = 1; } if (eacr.p1 && !etr_port1_uptodate) { etr_steai_cv(&etr_port1, ETR_STEAI_PORT_1); etr_port1_uptodate = 1; } } else { /* * One port was updated above, if the other * port is not uptodate toggle dp bit. */ if ((eacr.p0 && !etr_port0_uptodate) || (eacr.p1 && !etr_port1_uptodate)) eacr.dp ^= 1; else eacr.dp = 0; } return eacr; } /* * Write new etr control register if it differs from the current one. * Return 1 if etr_tolec has been updated as well. */ static void etr_update_eacr(struct etr_eacr eacr) { int dp_changed; if (memcmp(&etr_eacr, &eacr, sizeof(eacr)) == 0) /* No change, return. */ return; /* * The disable of an active port of the change of the data port * bit can/will cause a change in the data port. */ dp_changed = etr_eacr.e0 > eacr.e0 || etr_eacr.e1 > eacr.e1 || (etr_eacr.dp ^ eacr.dp) != 0; etr_eacr = eacr; etr_setr(&etr_eacr); if (dp_changed) etr_tolec = get_clock(); } /* * ETR work. In this function you'll find the main logic. In * particular this is the only function that calls etr_update_eacr(), * it "controls" the etr control register. */ static void etr_work_fn(struct work_struct *work) { unsigned long long now; struct etr_eacr eacr; struct etr_aib aib; int sync_port; /* prevent multiple execution. */ mutex_lock(&etr_work_mutex); /* Create working copy of etr_eacr. */ eacr = etr_eacr; /* Check for the different events and their immediate effects. */ eacr = etr_handle_events(eacr); /* Check if ETR is supposed to be active. */ eacr.ea = eacr.p0 || eacr.p1; if (!eacr.ea) { /* Both ports offline. Reset everything. */ eacr.dp = eacr.es = eacr.sl = 0; on_each_cpu(disable_sync_clock, NULL, 1); del_timer_sync(&etr_timer); etr_update_eacr(eacr); goto out_unlock; } /* Store aib to get the current ETR status word. */ BUG_ON(etr_stetr(&aib) != 0); etr_port0.esw = etr_port1.esw = aib.esw; /* Copy status word. */ now = get_clock(); /* * Update the port information if the last stepping port change * or data port change is older than 1.6 seconds. */ if (now >= etr_tolec + (1600000 << 12)) eacr = etr_handle_update(&aib, eacr); /* * Select ports to enable. The prefered synchronization mode is PPS. * If a port can be enabled depends on a number of things: * 1) The port needs to be online and uptodate. A port is not * disabled just because it is not uptodate, but it is only * enabled if it is uptodate. * 2) The port needs to have the same mode (pps / etr). * 3) The port needs to be usable -> etr_port_valid() == 1 * 4) To enable the second port the clock needs to be in sync. * 5) If both ports are useable and are ETR ports, the network id * has to be the same. * The eacr.sl bit is used to indicate etr mode vs. pps mode. */ if (eacr.p0 && aib.esw.psc0 == etr_lpsc_pps_mode) { eacr.sl = 0; eacr.e0 = 1; if (!etr_mode_is_pps(etr_eacr)) eacr.es = 0; if (!eacr.es || !eacr.p1 || aib.esw.psc1 != etr_lpsc_pps_mode) eacr.e1 = 0; // FIXME: uptodate checks ? else if (etr_port0_uptodate && etr_port1_uptodate) eacr.e1 = 1; sync_port = (etr_port0_uptodate && etr_port_valid(&etr_port0, 0)) ? 0 : -1; } else if (eacr.p1 && aib.esw.psc1 == etr_lpsc_pps_mode) { eacr.sl = 0; eacr.e0 = 0; eacr.e1 = 1; if (!etr_mode_is_pps(etr_eacr)) eacr.es = 0; sync_port = (etr_port1_uptodate && etr_port_valid(&etr_port1, 1)) ? 1 : -1; } else if (eacr.p0 && aib.esw.psc0 == etr_lpsc_operational_step) { eacr.sl = 1; eacr.e0 = 1; if (!etr_mode_is_etr(etr_eacr)) eacr.es = 0; if (!eacr.es || !eacr.p1 || aib.esw.psc1 != etr_lpsc_operational_alt) eacr.e1 = 0; else if (etr_port0_uptodate && etr_port1_uptodate && etr_compare_network(&etr_port0, &etr_port1)) eacr.e1 = 1; sync_port = (etr_port0_uptodate && etr_port_valid(&etr_port0, 0)) ? 0 : -1; } else if (eacr.p1 && aib.esw.psc1 == etr_lpsc_operational_step) { eacr.sl = 1; eacr.e0 = 0; eacr.e1 = 1; if (!etr_mode_is_etr(etr_eacr)) eacr.es = 0; sync_port = (etr_port1_uptodate && etr_port_valid(&etr_port1, 1)) ? 1 : -1; } else { /* Both ports not usable. */ eacr.es = eacr.sl = 0; sync_port = -1; } /* * If the clock is in sync just update the eacr and return. * If there is no valid sync port wait for a port update. */ if (check_sync_clock() || sync_port < 0) { etr_update_eacr(eacr); etr_set_tolec_timeout(now); goto out_unlock; } /* * Prepare control register for clock syncing * (reset data port bit, set sync check control. */ eacr.dp = 0; eacr.es = 1; /* * Update eacr and try to synchronize the clock. If the update * of eacr caused a stepping port switch (or if we have to * assume that a stepping port switch has occured) or the * clock syncing failed, reset the sync check control bit * and set up a timer to try again after 0.5 seconds */ etr_update_eacr(eacr); if (now < etr_tolec + (1600000 << 12) || etr_sync_clock_stop(&aib, sync_port) != 0) { /* Sync failed. Try again in 1/2 second. */ eacr.es = 0; etr_update_eacr(eacr); etr_set_sync_timeout(); } else etr_set_tolec_timeout(now); out_unlock: mutex_unlock(&etr_work_mutex); } /* * Sysfs interface functions */ static struct sysdev_class etr_sysclass = { .name = "etr", }; static struct sys_device etr_port0_dev = { .id = 0, .cls = &etr_sysclass, }; static struct sys_device etr_port1_dev = { .id = 1, .cls = &etr_sysclass, }; /* * ETR class attributes */ static ssize_t etr_stepping_port_show(struct sysdev_class *class, struct sysdev_class_attribute *attr, char *buf) { return sprintf(buf, "%i\n", etr_port0.esw.p); } static SYSDEV_CLASS_ATTR(stepping_port, 0400, etr_stepping_port_show, NULL); static ssize_t etr_stepping_mode_show(struct sysdev_class *class, struct sysdev_class_attribute *attr, char *buf) { char *mode_str; if (etr_mode_is_pps(etr_eacr)) mode_str = "pps"; else if (etr_mode_is_etr(etr_eacr)) mode_str = "etr"; else mode_str = "local"; return sprintf(buf, "%s\n", mode_str); } static SYSDEV_CLASS_ATTR(stepping_mode, 0400, etr_stepping_mode_show, NULL); /* * ETR port attributes */ static inline struct etr_aib *etr_aib_from_dev(struct sys_device *dev) { if (dev == &etr_port0_dev) return etr_port0_online ? &etr_port0 : NULL; else return etr_port1_online ? &etr_port1 : NULL; } static ssize_t etr_online_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { unsigned int online; online = (dev == &etr_port0_dev) ? etr_port0_online : etr_port1_online; return sprintf(buf, "%i\n", online); } static ssize_t etr_online_store(struct sys_device *dev, struct sysdev_attribute *attr, const char *buf, size_t count) { unsigned int value; value = simple_strtoul(buf, NULL, 0); if (value != 0 && value != 1) return -EINVAL; if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags)) return -EOPNOTSUPP; mutex_lock(&clock_sync_mutex); if (dev == &etr_port0_dev) { if (etr_port0_online == value) goto out; /* Nothing to do. */ etr_port0_online = value; if (etr_port0_online && etr_port1_online) set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); else clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags); set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); queue_work(time_sync_wq, &etr_work); } else { if (etr_port1_online == value) goto out; /* Nothing to do. */ etr_port1_online = value; if (etr_port0_online && etr_port1_online) set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); else clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags); set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); queue_work(time_sync_wq, &etr_work); } out: mutex_unlock(&clock_sync_mutex); return count; } static SYSDEV_ATTR(online, 0600, etr_online_show, etr_online_store); static ssize_t etr_stepping_control_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { return sprintf(buf, "%i\n", (dev == &etr_port0_dev) ? etr_eacr.e0 : etr_eacr.e1); } static SYSDEV_ATTR(stepping_control, 0400, etr_stepping_control_show, NULL); static ssize_t etr_mode_code_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { if (!etr_port0_online && !etr_port1_online) /* Status word is not uptodate if both ports are offline. */ return -ENODATA; return sprintf(buf, "%i\n", (dev == &etr_port0_dev) ? etr_port0.esw.psc0 : etr_port0.esw.psc1); } static SYSDEV_ATTR(state_code, 0400, etr_mode_code_show, NULL); static ssize_t etr_untuned_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); if (!aib || !aib->slsw.v1) return -ENODATA; return sprintf(buf, "%i\n", aib->edf1.u); } static SYSDEV_ATTR(untuned, 0400, etr_untuned_show, NULL); static ssize_t etr_network_id_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); if (!aib || !aib->slsw.v1) return -ENODATA; return sprintf(buf, "%i\n", aib->edf1.net_id); } static SYSDEV_ATTR(network, 0400, etr_network_id_show, NULL); static ssize_t etr_id_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); if (!aib || !aib->slsw.v1) return -ENODATA; return sprintf(buf, "%i\n", aib->edf1.etr_id); } static SYSDEV_ATTR(id, 0400, etr_id_show, NULL); static ssize_t etr_port_number_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); if (!aib || !aib->slsw.v1) return -ENODATA; return sprintf(buf, "%i\n", aib->edf1.etr_pn); } static SYSDEV_ATTR(port, 0400, etr_port_number_show, NULL); static ssize_t etr_coupled_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); if (!aib || !aib->slsw.v3) return -ENODATA; return sprintf(buf, "%i\n", aib->edf3.c); } static SYSDEV_ATTR(coupled, 0400, etr_coupled_show, NULL); static ssize_t etr_local_time_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); if (!aib || !aib->slsw.v3) return -ENODATA; return sprintf(buf, "%i\n", aib->edf3.blto); } static SYSDEV_ATTR(local_time, 0400, etr_local_time_show, NULL); static ssize_t etr_utc_offset_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); if (!aib || !aib->slsw.v3) return -ENODATA; return sprintf(buf, "%i\n", aib->edf3.buo); } static SYSDEV_ATTR(utc_offset, 0400, etr_utc_offset_show, NULL); static struct sysdev_attribute *etr_port_attributes[] = { &attr_online, &attr_stepping_control, &attr_state_code, &attr_untuned, &attr_network, &attr_id, &attr_port, &attr_coupled, &attr_local_time, &attr_utc_offset, NULL }; static int __init etr_register_port(struct sys_device *dev) { struct sysdev_attribute **attr; int rc; rc = sysdev_register(dev); if (rc) goto out; for (attr = etr_port_attributes; *attr; attr++) { rc = sysdev_create_file(dev, *attr); if (rc) goto out_unreg; } return 0; out_unreg: for (; attr >= etr_port_attributes; attr--) sysdev_remove_file(dev, *attr); sysdev_unregister(dev); out: return rc; } static void __init etr_unregister_port(struct sys_device *dev) { struct sysdev_attribute **attr; for (attr = etr_port_attributes; *attr; attr++) sysdev_remove_file(dev, *attr); sysdev_unregister(dev); } static int __init etr_init_sysfs(void) { int rc; rc = sysdev_class_register(&etr_sysclass); if (rc) goto out; rc = sysdev_class_create_file(&etr_sysclass, &attr_stepping_port); if (rc) goto out_unreg_class; rc = sysdev_class_create_file(&etr_sysclass, &attr_stepping_mode); if (rc) goto out_remove_stepping_port; rc = etr_register_port(&etr_port0_dev); if (rc) goto out_remove_stepping_mode; rc = etr_register_port(&etr_port1_dev); if (rc) goto out_remove_port0; return 0; out_remove_port0: etr_unregister_port(&etr_port0_dev); out_remove_stepping_mode: sysdev_class_remove_file(&etr_sysclass, &attr_stepping_mode); out_remove_stepping_port: sysdev_class_remove_file(&etr_sysclass, &attr_stepping_port); out_unreg_class: sysdev_class_unregister(&etr_sysclass); out: return rc; } device_initcall(etr_init_sysfs); /* * Server Time Protocol (STP) code. */ static int stp_online; static struct stp_sstpi stp_info; static void *stp_page; static void stp_work_fn(struct work_struct *work); static DEFINE_MUTEX(stp_work_mutex); static DECLARE_WORK(stp_work, stp_work_fn); static struct timer_list stp_timer; static int __init early_parse_stp(char *p) { if (strncmp(p, "off", 3) == 0) stp_online = 0; else if (strncmp(p, "on", 2) == 0) stp_online = 1; return 0; } early_param("stp", early_parse_stp); /* * Reset STP attachment. */ static void __init stp_reset(void) { int rc; stp_page = (void *) get_zeroed_page(GFP_ATOMIC); rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000); if (rc == 0) set_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags); else if (stp_online) { pr_warning("The real or virtual hardware system does " "not provide an STP interface\n"); free_page((unsigned long) stp_page); stp_page = NULL; stp_online = 0; } } static void stp_timeout(unsigned long dummy) { queue_work(time_sync_wq, &stp_work); } static int __init stp_init(void) { if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) return 0; setup_timer(&stp_timer, stp_timeout, 0UL); time_init_wq(); if (!stp_online) return 0; queue_work(time_sync_wq, &stp_work); return 0; } arch_initcall(stp_init); /* * STP timing alert. There are three causes: * 1) timing status change * 2) link availability change * 3) time control parameter change * In all three cases we are only interested in the clock source state. * If a STP clock source is now available use it. */ static void stp_timing_alert(struct stp_irq_parm *intparm) { if (intparm->tsc || intparm->lac || intparm->tcpc) queue_work(time_sync_wq, &stp_work); } /* * STP sync check machine check. This is called when the timing state * changes from the synchronized state to the unsynchronized state. * After a STP sync check the clock is not in sync. The machine check * is broadcasted to all cpus at the same time. */ void stp_sync_check(void) { disable_sync_clock(NULL); queue_work(time_sync_wq, &stp_work); } /* * STP island condition machine check. This is called when an attached * server attempts to communicate over an STP link and the servers * have matching CTN ids and have a valid stratum-1 configuration * but the configurations do not match. */ void stp_island_check(void) { disable_sync_clock(NULL); queue_work(time_sync_wq, &stp_work); } static int stp_sync_clock(void *data) { static int first; unsigned long long old_clock, delta; struct clock_sync_data *stp_sync; int rc; stp_sync = data; if (xchg(&first, 1) == 1) { /* Slave */ clock_sync_cpu(stp_sync); return 0; } /* Wait until all other cpus entered the sync function. */ while (atomic_read(&stp_sync->cpus) != 0) cpu_relax(); enable_sync_clock(); rc = 0; if (stp_info.todoff[0] || stp_info.todoff[1] || stp_info.todoff[2] || stp_info.todoff[3] || stp_info.tmd != 2) { old_clock = get_clock(); rc = chsc_sstpc(stp_page, STP_OP_SYNC, 0); if (rc == 0) { delta = adjust_time(old_clock, get_clock(), 0); fixup_clock_comparator(delta); rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi)); if (rc == 0 && stp_info.tmd != 2) rc = -EAGAIN; } } if (rc) { disable_sync_clock(NULL); stp_sync->in_sync = -EAGAIN; } else stp_sync->in_sync = 1; xchg(&first, 0); return 0; } /* * STP work. Check for the STP state and take over the clock * synchronization if the STP clock source is usable. */ static void stp_work_fn(struct work_struct *work) { struct clock_sync_data stp_sync; int rc; /* prevent multiple execution. */ mutex_lock(&stp_work_mutex); if (!stp_online) { chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000); del_timer_sync(&stp_timer); goto out_unlock; } rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0xb0e0); if (rc) goto out_unlock; rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi)); if (rc || stp_info.c == 0) goto out_unlock; /* Skip synchronization if the clock is already in sync. */ if (check_sync_clock()) goto out_unlock; memset(&stp_sync, 0, sizeof(stp_sync)); get_online_cpus(); atomic_set(&stp_sync.cpus, num_online_cpus() - 1); stop_machine(stp_sync_clock, &stp_sync, &cpu_online_map); put_online_cpus(); if (!check_sync_clock()) /* * There is a usable clock but the synchonization failed. * Retry after a second. */ mod_timer(&stp_timer, jiffies + HZ); out_unlock: mutex_unlock(&stp_work_mutex); } /* * STP class sysfs interface functions */ static struct sysdev_class stp_sysclass = { .name = "stp", }; static ssize_t stp_ctn_id_show(struct sysdev_class *class, struct sysdev_class_attribute *attr, char *buf) { if (!stp_online) return -ENODATA; return sprintf(buf, "%016llx\n", *(unsigned long long *) stp_info.ctnid); } static SYSDEV_CLASS_ATTR(ctn_id, 0400, stp_ctn_id_show, NULL); static ssize_t stp_ctn_type_show(struct sysdev_class *class, struct sysdev_class_attribute *attr, char *buf) { if (!stp_online) return -ENODATA; return sprintf(buf, "%i\n", stp_info.ctn); } static SYSDEV_CLASS_ATTR(ctn_type, 0400, stp_ctn_type_show, NULL); static ssize_t stp_dst_offset_show(struct sysdev_class *class, struct sysdev_class_attribute *attr, char *buf) { if (!stp_online || !(stp_info.vbits & 0x2000)) return -ENODATA; return sprintf(buf, "%i\n", (int)(s16) stp_info.dsto); } static SYSDEV_CLASS_ATTR(dst_offset, 0400, stp_dst_offset_show, NULL); static ssize_t stp_leap_seconds_show(struct sysdev_class *class, struct sysdev_class_attribute *attr, char *buf) { if (!stp_online || !(stp_info.vbits & 0x8000)) return -ENODATA; return sprintf(buf, "%i\n", (int)(s16) stp_info.leaps); } static SYSDEV_CLASS_ATTR(leap_seconds, 0400, stp_leap_seconds_show, NULL); static ssize_t stp_stratum_show(struct sysdev_class *class, struct sysdev_class_attribute *attr, char *buf) { if (!stp_online) return -ENODATA; return sprintf(buf, "%i\n", (int)(s16) stp_info.stratum); } static SYSDEV_CLASS_ATTR(stratum, 0400, stp_stratum_show, NULL); static ssize_t stp_time_offset_show(struct sysdev_class *class, struct sysdev_class_attribute *attr, char *buf) { if (!stp_online || !(stp_info.vbits & 0x0800)) return -ENODATA; return sprintf(buf, "%i\n", (int) stp_info.tto); } static SYSDEV_CLASS_ATTR(time_offset, 0400, stp_time_offset_show, NULL); static ssize_t stp_time_zone_offset_show(struct sysdev_class *class, struct sysdev_class_attribute *attr, char *buf) { if (!stp_online || !(stp_info.vbits & 0x4000)) return -ENODATA; return sprintf(buf, "%i\n", (int)(s16) stp_info.tzo); } static SYSDEV_CLASS_ATTR(time_zone_offset, 0400, stp_time_zone_offset_show, NULL); static ssize_t stp_timing_mode_show(struct sysdev_class *class, struct sysdev_class_attribute *attr, char *buf) { if (!stp_online) return -ENODATA; return sprintf(buf, "%i\n", stp_info.tmd); } static SYSDEV_CLASS_ATTR(timing_mode, 0400, stp_timing_mode_show, NULL); static ssize_t stp_timing_state_show(struct sysdev_class *class, struct sysdev_class_attribute *attr, char *buf) { if (!stp_online) return -ENODATA; return sprintf(buf, "%i\n", stp_info.tst); } static SYSDEV_CLASS_ATTR(timing_state, 0400, stp_timing_state_show, NULL); static ssize_t stp_online_show(struct sysdev_class *class, struct sysdev_class_attribute *attr, char *buf) { return sprintf(buf, "%i\n", stp_online); } static ssize_t stp_online_store(struct sysdev_class *class, struct sysdev_class_attribute *attr, const char *buf, size_t count) { unsigned int value; value = simple_strtoul(buf, NULL, 0); if (value != 0 && value != 1) return -EINVAL; if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) return -EOPNOTSUPP; mutex_lock(&clock_sync_mutex); stp_online = value; if (stp_online) set_bit(CLOCK_SYNC_STP, &clock_sync_flags); else clear_bit(CLOCK_SYNC_STP, &clock_sync_flags); queue_work(time_sync_wq, &stp_work); mutex_unlock(&clock_sync_mutex); return count; } /* * Can't use SYSDEV_CLASS_ATTR because the attribute should be named * stp/online but attr_online already exists in this file ..


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