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-rw-r--r--drivers/ptp/Kconfig12
-rw-r--r--drivers/ptp/Makefile1
-rw-r--r--drivers/ptp/ptp_clock.c22
-rw-r--r--drivers/ptp/ptp_kvm.c207
-rw-r--r--drivers/ptp/ptp_private.h7
-rw-r--r--drivers/ptp/ptp_sysfs.c167
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);
}