From bfcbb76b0f595ea9ede9f7a218086fef85242f10 Mon Sep 17 00:00:00 2001 From: Miroslav Lichvar Date: Wed, 2 Feb 2022 10:33:55 +0100 Subject: [PATCH 1/4] ptp: unregister virtual clocks when unregistering physical clock. When unregistering a physical clock which has some virtual clocks, unregister the virtual clocks with it. This fixes the following oops, which can be triggered by unloading a driver providing a PTP clock when it has enabled virtual clocks: BUG: unable to handle page fault for address: ffffffffc04fc4d8 Oops: 0000 [#1] PREEMPT SMP NOPTI RIP: 0010:ptp_vclock_read+0x31/0xb0 Call Trace: timecounter_read+0xf/0x50 ptp_vclock_refresh+0x2c/0x50 ? ptp_clock_release+0x40/0x40 ptp_aux_kworker+0x17/0x30 kthread_worker_fn+0x9b/0x240 ? kthread_should_park+0x30/0x30 kthread+0xe2/0x110 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x22/0x30 Fixes: 73f37068d540 ("ptp: support ptp physical/virtual clocks conversion") Signed-off-by: Miroslav Lichvar Acked-by: Richard Cochran Cc: Yangbo Lu Cc: Yang Yingliang Signed-off-by: David S. Miller --- drivers/ptp/ptp_clock.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c index 0e4bc8b9329d..b6f2cfd15dd2 100644 --- a/drivers/ptp/ptp_clock.c +++ b/drivers/ptp/ptp_clock.c @@ -317,11 +317,18 @@ no_memory: } EXPORT_SYMBOL(ptp_clock_register); +static int unregister_vclock(struct device *dev, void *data) +{ + struct ptp_clock *ptp = dev_get_drvdata(dev); + + ptp_vclock_unregister(info_to_vclock(ptp->info)); + return 0; +} + int ptp_clock_unregister(struct ptp_clock *ptp) { if (ptp_vclock_in_use(ptp)) { - pr_err("ptp: virtual clock in use\n"); - return -EBUSY; + device_for_each_child(&ptp->dev, NULL, unregister_vclock); } ptp->defunct = 1; From f77222d693cc04a881bcd0bded3dd1229c70d7ef Mon Sep 17 00:00:00 2001 From: Miroslav Lichvar Date: Wed, 2 Feb 2022 10:33:56 +0100 Subject: [PATCH 2/4] ptp: increase maximum adjustment of virtual clocks. Increase the maximum frequency offset of virtual clocks to 50% to enable faster slewing corrections. This value cannot be represented as scaled ppm when long has 32 bits, but that is already the case for other drivers, even those that provide the adjfine() function, i.e. 32-bit applications are expected to check for the limit. Signed-off-by: Miroslav Lichvar Acked-by: Richard Cochran Cc: Yangbo Lu Signed-off-by: David S. Miller --- drivers/ptp/ptp_vclock.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/ptp/ptp_vclock.c b/drivers/ptp/ptp_vclock.c index ab1d233173e1..5aa2b32d9dc7 100644 --- a/drivers/ptp/ptp_vclock.c +++ b/drivers/ptp/ptp_vclock.c @@ -84,8 +84,7 @@ static long ptp_vclock_refresh(struct ptp_clock_info *ptp) static const struct ptp_clock_info ptp_vclock_info = { .owner = THIS_MODULE, .name = "ptp virtual clock", - /* The maximum ppb value that long scaled_ppm can support */ - .max_adj = 32767999, + .max_adj = 500000000, .adjfine = ptp_vclock_adjfine, .adjtime = ptp_vclock_adjtime, .gettime64 = ptp_vclock_gettime, From f0067ebfc42b0f5bb5472fca9fcd4d4fa87a08c0 Mon Sep 17 00:00:00 2001 From: Miroslav Lichvar Date: Wed, 2 Feb 2022 10:33:57 +0100 Subject: [PATCH 3/4] ptp: add gettimex64() to virtual clocks. If the physical clock has the gettimex64() function, provide a gettimex64() wrapper in the virtual clock to enable more accurate and stable synchronization. This adds support for the PTP_SYS_OFFSET_EXTENDED ioctl. Signed-off-by: Miroslav Lichvar Acked-by: Richard Cochran Cc: Yangbo Lu Signed-off-by: David S. Miller --- drivers/ptp/ptp_vclock.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/drivers/ptp/ptp_vclock.c b/drivers/ptp/ptp_vclock.c index 5aa2b32d9dc7..2f0b46386176 100644 --- a/drivers/ptp/ptp_vclock.c +++ b/drivers/ptp/ptp_vclock.c @@ -57,6 +57,30 @@ static int ptp_vclock_gettime(struct ptp_clock_info *ptp, return 0; } +static int ptp_vclock_gettimex(struct ptp_clock_info *ptp, + struct timespec64 *ts, + struct ptp_system_timestamp *sts) +{ + struct ptp_vclock *vclock = info_to_vclock(ptp); + struct ptp_clock *pptp = vclock->pclock; + struct timespec64 pts; + unsigned long flags; + int err; + u64 ns; + + err = pptp->info->gettimex64(pptp->info, &pts, sts); + if (err) + return err; + + spin_lock_irqsave(&vclock->lock, flags); + ns = timecounter_cyc2time(&vclock->tc, timespec64_to_ns(&pts)); + spin_unlock_irqrestore(&vclock->lock, flags); + + *ts = ns_to_timespec64(ns); + + return 0; +} + static int ptp_vclock_settime(struct ptp_clock_info *ptp, const struct timespec64 *ts) { @@ -87,7 +111,6 @@ static const struct ptp_clock_info ptp_vclock_info = { .max_adj = 500000000, .adjfine = ptp_vclock_adjfine, .adjtime = ptp_vclock_adjtime, - .gettime64 = ptp_vclock_gettime, .settime64 = ptp_vclock_settime, .do_aux_work = ptp_vclock_refresh, }; @@ -123,6 +146,10 @@ struct ptp_vclock *ptp_vclock_register(struct ptp_clock *pclock) vclock->pclock = pclock; vclock->info = ptp_vclock_info; + if (pclock->info->gettimex64) + vclock->info.gettimex64 = ptp_vclock_gettimex; + else + vclock->info.gettime64 = ptp_vclock_gettime; vclock->cc = ptp_vclock_cc; snprintf(vclock->info.name, PTP_CLOCK_NAME_LEN, "ptp%d_virt", From 21fad63084c22128169eca1b9d1136eabb8cd290 Mon Sep 17 00:00:00 2001 From: Miroslav Lichvar Date: Wed, 2 Feb 2022 10:33:58 +0100 Subject: [PATCH 4/4] ptp: add getcrosststamp() to virtual clocks. If the physical clock supports cross timestamping (it has the getcrosststamp() function), provide a wrapper in the virtual clock to enable cross timestamping. This adds support for the PTP_SYS_OFFSET_PRECISE ioctl. Signed-off-by: Miroslav Lichvar Acked-by: Richard Cochran Cc: Yangbo Lu Signed-off-by: David S. Miller --- drivers/ptp/ptp_vclock.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/drivers/ptp/ptp_vclock.c b/drivers/ptp/ptp_vclock.c index 2f0b46386176..cb179a3ea508 100644 --- a/drivers/ptp/ptp_vclock.c +++ b/drivers/ptp/ptp_vclock.c @@ -95,6 +95,28 @@ static int ptp_vclock_settime(struct ptp_clock_info *ptp, return 0; } +static int ptp_vclock_getcrosststamp(struct ptp_clock_info *ptp, + struct system_device_crosststamp *xtstamp) +{ + struct ptp_vclock *vclock = info_to_vclock(ptp); + struct ptp_clock *pptp = vclock->pclock; + unsigned long flags; + int err; + u64 ns; + + err = pptp->info->getcrosststamp(pptp->info, xtstamp); + if (err) + return err; + + spin_lock_irqsave(&vclock->lock, flags); + ns = timecounter_cyc2time(&vclock->tc, ktime_to_ns(xtstamp->device)); + spin_unlock_irqrestore(&vclock->lock, flags); + + xtstamp->device = ns_to_ktime(ns); + + return 0; +} + static long ptp_vclock_refresh(struct ptp_clock_info *ptp) { struct ptp_vclock *vclock = info_to_vclock(ptp); @@ -150,6 +172,8 @@ struct ptp_vclock *ptp_vclock_register(struct ptp_clock *pclock) vclock->info.gettimex64 = ptp_vclock_gettimex; else vclock->info.gettime64 = ptp_vclock_gettime; + if (pclock->info->getcrosststamp) + vclock->info.getcrosststamp = ptp_vclock_getcrosststamp; vclock->cc = ptp_vclock_cc; snprintf(vclock->info.name, PTP_CLOCK_NAME_LEN, "ptp%d_virt",