diff options
Diffstat (limited to 'drivers/ptp')
| -rw-r--r-- | drivers/ptp/Kconfig | 12 | ||||
| -rw-r--r-- | drivers/ptp/Makefile | 1 | ||||
| -rw-r--r-- | drivers/ptp/ptp_clock.c | 22 | ||||
| -rw-r--r-- | drivers/ptp/ptp_kvm.c | 207 | ||||
| -rw-r--r-- | drivers/ptp/ptp_private.h | 7 | ||||
| -rw-r--r-- | drivers/ptp/ptp_sysfs.c | 167 |
6 files changed, 300 insertions, 116 deletions
diff --git a/drivers/ptp/Kconfig b/drivers/ptp/Kconfig index bdce33291161..384f661a6496 100644 --- a/drivers/ptp/Kconfig +++ b/drivers/ptp/Kconfig @@ -90,4 +90,16 @@ config PTP_1588_CLOCK_PCH To compile this driver as a module, choose M here: the module will be called ptp_pch. +config PTP_1588_CLOCK_KVM + tristate "KVM virtual PTP clock" + depends on PTP_1588_CLOCK + depends on KVM_GUEST && X86 + default y + help + This driver adds support for using kvm infrastructure as a PTP + clock. This clock is only useful if you are using KVM guests. + + To compile this driver as a module, choose M here: the module + will be called ptp_kvm. + endmenu diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile index 8b58597298de..530736161a8b 100644 --- a/drivers/ptp/Makefile +++ b/drivers/ptp/Makefile @@ -6,3 +6,4 @@ ptp-y := ptp_clock.o ptp_chardev.o ptp_sysfs.o obj-$(CONFIG_PTP_1588_CLOCK) += ptp.o obj-$(CONFIG_PTP_1588_CLOCK_IXP46X) += ptp_ixp46x.o obj-$(CONFIG_PTP_1588_CLOCK_PCH) += ptp_pch.o +obj-$(CONFIG_PTP_1588_CLOCK_KVM) += ptp_kvm.o diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c index 9c13381b6966..e8142803a1a7 100644 --- a/drivers/ptp/ptp_clock.c +++ b/drivers/ptp/ptp_clock.c @@ -221,18 +221,17 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, mutex_init(&ptp->pincfg_mux); init_waitqueue_head(&ptp->tsev_wq); + err = ptp_populate_pin_groups(ptp); + if (err) + goto no_pin_groups; + /* Create a new device in our class. */ - ptp->dev = device_create(ptp_class, parent, ptp->devid, ptp, - "ptp%d", ptp->index); + ptp->dev = device_create_with_groups(ptp_class, parent, ptp->devid, + ptp, ptp->pin_attr_groups, + "ptp%d", ptp->index); if (IS_ERR(ptp->dev)) goto no_device; - dev_set_drvdata(ptp->dev, ptp); - - err = ptp_populate_sysfs(ptp); - if (err) - goto no_sysfs; - /* Register a new PPS source. */ if (info->pps) { struct pps_source_info pps; @@ -260,10 +259,10 @@ no_clock: if (ptp->pps_source) pps_unregister_source(ptp->pps_source); no_pps: - ptp_cleanup_sysfs(ptp); -no_sysfs: device_destroy(ptp_class, ptp->devid); no_device: + ptp_cleanup_pin_groups(ptp); +no_pin_groups: mutex_destroy(&ptp->tsevq_mux); mutex_destroy(&ptp->pincfg_mux); ida_simple_remove(&ptp_clocks_map, index); @@ -282,8 +281,9 @@ int ptp_clock_unregister(struct ptp_clock *ptp) /* Release the clock's resources. */ if (ptp->pps_source) pps_unregister_source(ptp->pps_source); - ptp_cleanup_sysfs(ptp); + device_destroy(ptp_class, ptp->devid); + ptp_cleanup_pin_groups(ptp); posix_clock_unregister(&ptp->clock); return 0; diff --git a/drivers/ptp/ptp_kvm.c b/drivers/ptp/ptp_kvm.c new file mode 100644 index 000000000000..09b4df74291e --- /dev/null +++ b/drivers/ptp/ptp_kvm.c @@ -0,0 +1,207 @@ +/* + * Virtual PTP 1588 clock for use with KVM guests + * + * Copyright (C) 2017 Red Hat Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ +#include <linux/device.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <uapi/linux/kvm_para.h> +#include <asm/kvm_para.h> +#include <asm/pvclock.h> +#include <asm/kvmclock.h> +#include <uapi/asm/kvm_para.h> + +#include <linux/ptp_clock_kernel.h> + +struct kvm_ptp_clock { + struct ptp_clock *ptp_clock; + struct ptp_clock_info caps; +}; + +DEFINE_SPINLOCK(kvm_ptp_lock); + +static struct pvclock_vsyscall_time_info *hv_clock; + +static struct kvm_clock_pairing clock_pair; +static phys_addr_t clock_pair_gpa; + +static int ptp_kvm_get_time_fn(ktime_t *device_time, + struct system_counterval_t *system_counter, + void *ctx) +{ + unsigned long ret; + struct timespec64 tspec; + unsigned version; + int cpu; + struct pvclock_vcpu_time_info *src; + + spin_lock(&kvm_ptp_lock); + + preempt_disable_notrace(); + cpu = smp_processor_id(); + src = &hv_clock[cpu].pvti; + + do { + /* + * We are using a TSC value read in the hosts + * kvm_hc_clock_pairing handling. + * So any changes to tsc_to_system_mul + * and tsc_shift or any other pvclock + * data invalidate that measurement. + */ + version = pvclock_read_begin(src); + + ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, + clock_pair_gpa, + KVM_CLOCK_PAIRING_WALLCLOCK); + if (ret != 0) { + pr_err_ratelimited("clock pairing hypercall ret %lu\n", ret); + spin_unlock(&kvm_ptp_lock); + preempt_enable_notrace(); + return -EOPNOTSUPP; + } + + tspec.tv_sec = clock_pair.sec; + tspec.tv_nsec = clock_pair.nsec; + ret = __pvclock_read_cycles(src, clock_pair.tsc); + } while (pvclock_read_retry(src, version)); + + preempt_enable_notrace(); + + system_counter->cycles = ret; + system_counter->cs = &kvm_clock; + + *device_time = timespec64_to_ktime(tspec); + + spin_unlock(&kvm_ptp_lock); + + return 0; +} + +static int ptp_kvm_getcrosststamp(struct ptp_clock_info *ptp, + struct system_device_crosststamp *xtstamp) +{ + return get_device_system_crosststamp(ptp_kvm_get_time_fn, NULL, + NULL, xtstamp); +} + +/* + * PTP clock operations + */ + +static int ptp_kvm_adjfreq(struct ptp_clock_info *ptp, s32 ppb) +{ + return -EOPNOTSUPP; +} + +static int ptp_kvm_adjtime(struct ptp_clock_info *ptp, s64 delta) +{ + return -EOPNOTSUPP; +} + +static int ptp_kvm_settime(struct ptp_clock_info *ptp, + const struct timespec64 *ts) +{ + return -EOPNOTSUPP; +} + +static int ptp_kvm_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts) +{ + unsigned long ret; + struct timespec64 tspec; + + spin_lock(&kvm_ptp_lock); + + ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, + clock_pair_gpa, + KVM_CLOCK_PAIRING_WALLCLOCK); + if (ret != 0) { + pr_err_ratelimited("clock offset hypercall ret %lu\n", ret); + spin_unlock(&kvm_ptp_lock); + return -EOPNOTSUPP; + } + + tspec.tv_sec = clock_pair.sec; + tspec.tv_nsec = clock_pair.nsec; + spin_unlock(&kvm_ptp_lock); + + memcpy(ts, &tspec, sizeof(struct timespec64)); + + return 0; +} + +static int ptp_kvm_enable(struct ptp_clock_info *ptp, + struct ptp_clock_request *rq, int on) +{ + return -EOPNOTSUPP; +} + +static struct ptp_clock_info ptp_kvm_caps = { + .owner = THIS_MODULE, + .name = "KVM virtual PTP", + .max_adj = 0, + .n_ext_ts = 0, + .n_pins = 0, + .pps = 0, + .adjfreq = ptp_kvm_adjfreq, + .adjtime = ptp_kvm_adjtime, + .gettime64 = ptp_kvm_gettime, + .settime64 = ptp_kvm_settime, + .enable = ptp_kvm_enable, + .getcrosststamp = ptp_kvm_getcrosststamp, +}; + +/* module operations */ + +static struct kvm_ptp_clock kvm_ptp_clock; + +static void __exit ptp_kvm_exit(void) +{ + ptp_clock_unregister(kvm_ptp_clock.ptp_clock); +} + +static int __init ptp_kvm_init(void) +{ + long ret; + + clock_pair_gpa = slow_virt_to_phys(&clock_pair); + hv_clock = pvclock_pvti_cpu0_va(); + + if (!hv_clock) + return -ENODEV; + + ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, clock_pair_gpa, + KVM_CLOCK_PAIRING_WALLCLOCK); + if (ret == -KVM_ENOSYS || ret == -KVM_EOPNOTSUPP) + return -ENODEV; + + kvm_ptp_clock.caps = ptp_kvm_caps; + + kvm_ptp_clock.ptp_clock = ptp_clock_register(&kvm_ptp_clock.caps, NULL); + + if (IS_ERR(kvm_ptp_clock.ptp_clock)) + return PTR_ERR(kvm_ptp_clock.ptp_clock); + + return 0; +} + +module_init(ptp_kvm_init); +module_exit(ptp_kvm_exit); + +MODULE_AUTHOR("Marcelo Tosatti <mtosatti@redhat.com>"); +MODULE_DESCRIPTION("PTP clock using KVMCLOCK"); +MODULE_LICENSE("GPL"); diff --git a/drivers/ptp/ptp_private.h b/drivers/ptp/ptp_private.h index 9c5d41421b65..d95888974d0c 100644 --- a/drivers/ptp/ptp_private.h +++ b/drivers/ptp/ptp_private.h @@ -54,6 +54,8 @@ struct ptp_clock { struct device_attribute *pin_dev_attr; struct attribute **pin_attr; struct attribute_group pin_attr_group; + /* 1st entry is a pointer to the real group, 2nd is NULL terminator */ + const struct attribute_group *pin_attr_groups[2]; }; /* @@ -94,8 +96,7 @@ uint ptp_poll(struct posix_clock *pc, extern const struct attribute_group *ptp_groups[]; -int ptp_cleanup_sysfs(struct ptp_clock *ptp); - -int ptp_populate_sysfs(struct ptp_clock *ptp); +int ptp_populate_pin_groups(struct ptp_clock *ptp); +void ptp_cleanup_pin_groups(struct ptp_clock *ptp); #endif diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c index 53d43954a974..48401dfcd999 100644 --- a/drivers/ptp/ptp_sysfs.c +++ b/drivers/ptp/ptp_sysfs.c @@ -46,27 +46,6 @@ PTP_SHOW_INT(n_periodic_outputs, n_per_out); PTP_SHOW_INT(n_programmable_pins, n_pins); PTP_SHOW_INT(pps_available, pps); -static struct attribute *ptp_attrs[] = { - &dev_attr_clock_name.attr, - &dev_attr_max_adjustment.attr, - &dev_attr_n_alarms.attr, - &dev_attr_n_external_timestamps.attr, - &dev_attr_n_periodic_outputs.attr, - &dev_attr_n_programmable_pins.attr, - &dev_attr_pps_available.attr, - NULL, -}; - -static const struct attribute_group ptp_group = { - .attrs = ptp_attrs, -}; - -const struct attribute_group *ptp_groups[] = { - &ptp_group, - NULL, -}; - - static ssize_t extts_enable_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) @@ -91,6 +70,7 @@ static ssize_t extts_enable_store(struct device *dev, out: return err; } +static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store); static ssize_t extts_fifo_show(struct device *dev, struct device_attribute *attr, char *page) @@ -124,6 +104,7 @@ out: mutex_unlock(&ptp->tsevq_mux); return cnt; } +static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL); static ssize_t period_store(struct device *dev, struct device_attribute *attr, @@ -151,6 +132,7 @@ static ssize_t period_store(struct device *dev, out: return err; } +static DEVICE_ATTR(period, 0220, NULL, period_store); static ssize_t pps_enable_store(struct device *dev, struct device_attribute *attr, @@ -177,6 +159,57 @@ static ssize_t pps_enable_store(struct device *dev, out: return err; } +static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store); + +static struct attribute *ptp_attrs[] = { + &dev_attr_clock_name.attr, + + &dev_attr_max_adjustment.attr, + &dev_attr_n_alarms.attr, + &dev_attr_n_external_timestamps.attr, + &dev_attr_n_periodic_outputs.attr, + &dev_attr_n_programmable_pins.attr, + &dev_attr_pps_available.attr, + + &dev_attr_extts_enable.attr, + &dev_attr_fifo.attr, + &dev_attr_period.attr, + &dev_attr_pps_enable.attr, + NULL +}; + +static umode_t ptp_is_attribute_visible(struct kobject *kobj, + struct attribute *attr, int n) +{ + struct device *dev = kobj_to_dev(kobj); + struct ptp_clock *ptp = dev_get_drvdata(dev); + struct ptp_clock_info *info = ptp->info; + umode_t mode = attr->mode; + + if (attr == &dev_attr_extts_enable.attr || + attr == &dev_attr_fifo.attr) { + if (!info->n_ext_ts) + mode = 0; + } else if (attr == &dev_attr_period.attr) { + if (!info->n_per_out) + mode = 0; + } else if (attr == &dev_attr_pps_enable.attr) { + if (!info->pps) + mode = 0; + } + + return mode; +} + +static const struct attribute_group ptp_group = { + .is_visible = ptp_is_attribute_visible, + .attrs = ptp_attrs, +}; + +const struct attribute_group *ptp_groups[] = { + &ptp_group, + NULL +}; static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name) { @@ -235,47 +268,20 @@ static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr, return count; } -static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store); -static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL); -static DEVICE_ATTR(period, 0220, NULL, period_store); -static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store); - -int ptp_cleanup_sysfs(struct ptp_clock *ptp) +int ptp_populate_pin_groups(struct ptp_clock *ptp) { - struct device *dev = ptp->dev; - struct ptp_clock_info *info = ptp->info; - - if (info->n_ext_ts) { - device_remove_file(dev, &dev_attr_extts_enable); - device_remove_file(dev, &dev_attr_fifo); - } - if (info->n_per_out) - device_remove_file(dev, &dev_attr_period); - - if (info->pps) - device_remove_file(dev, &dev_attr_pps_enable); - - if (info->n_pins) { - sysfs_remove_group(&dev->kobj, &ptp->pin_attr_group); - kfree(ptp->pin_attr); - kfree(ptp->pin_dev_attr); - } - return 0; -} - -static int ptp_populate_pins(struct ptp_clock *ptp) -{ - struct device *dev = ptp->dev; struct ptp_clock_info *info = ptp->info; int err = -ENOMEM, i, n_pins = info->n_pins; - ptp->pin_dev_attr = kzalloc(n_pins * sizeof(*ptp->pin_dev_attr), + if (!n_pins) + return 0; + + ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr), GFP_KERNEL); if (!ptp->pin_dev_attr) goto no_dev_attr; - ptp->pin_attr = kzalloc((1 + n_pins) * sizeof(struct attribute *), - GFP_KERNEL); + ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL); if (!ptp->pin_attr) goto no_pin_attr; @@ -292,61 +298,18 @@ static int ptp_populate_pins(struct ptp_clock *ptp) ptp->pin_attr_group.name = "pins"; ptp->pin_attr_group.attrs = ptp->pin_attr; - err = sysfs_create_group(&dev->kobj, &ptp->pin_attr_group); - if (err) - goto no_group; + ptp->pin_attr_groups[0] = &ptp->pin_attr_group; + return 0; -no_group: - kfree(ptp->pin_attr); no_pin_attr: kfree(ptp->pin_dev_attr); no_dev_attr: return err; } -int ptp_populate_sysfs(struct ptp_clock *ptp) +void ptp_cleanup_pin_groups(struct ptp_clock *ptp) { - struct device *dev = ptp->dev; - struct ptp_clock_info *info = ptp->info; - int err; - - if (info->n_ext_ts) { - err = device_create_file(dev, &dev_attr_extts_enable); - if (err) - goto out1; - err = device_create_file(dev, &dev_attr_fifo); - if (err) - goto out2; - } - if (info->n_per_out) { - err = device_create_file(dev, &dev_attr_period); - if (err) - goto out3; - } - if (info->pps) { - err = device_create_file(dev, &dev_attr_pps_enable); - if (err) - goto out4; - } - if (info->n_pins) { - err = ptp_populate_pins(ptp); - if (err) - goto out5; - } - return 0; -out5: - if (info->pps) - device_remove_file(dev, &dev_attr_pps_enable); -out4: - if (info->n_per_out) - device_remove_file(dev, &dev_attr_period); -out3: - if (info->n_ext_ts) - device_remove_file(dev, &dev_attr_fifo); -out2: - if (info->n_ext_ts) - device_remove_file(dev, &dev_attr_extts_enable); -out1: - return err; + kfree(ptp->pin_attr); + kfree(ptp->pin_dev_attr); } |