Merge branch 'ptp-belated-spring-cleaning-of-the-chardev-driver'

Thomas Gleixner says:

====================
ptp: Belated spring cleaning of the chardev driver

When looking into supporting auxiliary clocks in the PTP ioctl, the
inpenetrable ptp_ioctl() letter soup bothered me enough to clean it up.

The code (~400 lines!) is really hard to follow due to a gazillion of
local variables, which are only used in certain case scopes, and a
mixture of gotos, breaks and direct error return paths.

Clean it up by splitting out the IOCTL functionality into seperate
functions, which contain only the required local variables and are trivial
to follow. Complete the cleanup by converting the code to lock guards and
get rid of all gotos.

That reduces the code size by 48 lines and also the binary text size is
80 bytes smaller than the current maze.

The series is split up into one patch per IOCTL command group for easy
review.

v1: https://lore.kernel.org/20250620130144.351492917@linutronix.de
====================

Link: https://patch.msgid.link/20250625114404.102196103@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 341 insertions, 393 deletions

diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
index 4bf421765d03..6b611fe5a95e 100644
--- a/drivers/ptp/ptp_chardev.c
+++ b/drivers/ptp/ptp_chardev.c
@@ -106,11 +106,9 @@ int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
 
 int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode)
 {
-	struct ptp_clock *ptp =
-		container_of(pccontext->clk, struct ptp_clock, clock);
+	struct ptp_clock *ptp = container_of(pccontext->clk, struct ptp_clock, clock);
 	struct timestamp_event_queue *queue;
 	char debugfsname[32];
-	unsigned long flags;
 
 	queue = kzalloc(sizeof(*queue), GFP_KERNEL);
 	if (!queue)
@@ -122,9 +120,8 @@ int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode)
 	}
 	bitmap_set(queue->mask, 0, PTP_MAX_CHANNELS);
 	spin_lock_init(&queue->lock);
-	spin_lock_irqsave(&ptp->tsevqs_lock, flags);
-	list_add_tail(&queue->qlist, &ptp->tsevqs);
-	spin_unlock_irqrestore(&ptp->tsevqs_lock, flags);
+	scoped_guard(spinlock_irq, &ptp->tsevqs_lock)
+		list_add_tail(&queue->qlist, &ptp->tsevqs);
 	pccontext->private_clkdata = queue;
 
 	/* Debugfs contents */
@@ -143,402 +140,378 @@ int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode)
 int ptp_release(struct posix_clock_context *pccontext)
 {
 	struct timestamp_event_queue *queue = pccontext->private_clkdata;
-	unsigned long flags;
 	struct ptp_clock *ptp =
 		container_of(pccontext->clk, struct ptp_clock, clock);
 
 	debugfs_remove(queue->debugfs_instance);
 	pccontext->private_clkdata = NULL;
-	spin_lock_irqsave(&ptp->tsevqs_lock, flags);
-	list_del(&queue->qlist);
-	spin_unlock_irqrestore(&ptp->tsevqs_lock, flags);
+	scoped_guard(spinlock_irq, &ptp->tsevqs_lock)
+		list_del(&queue->qlist);
 	bitmap_free(queue->mask);
 	kfree(queue);
 	return 0;
 }
 
-long ptp_ioctl(struct posix_clock_context *pccontext, unsigned int cmd,
-	       unsigned long arg)
+static long ptp_clock_getcaps(struct ptp_clock *ptp, void __user *arg)
+{
+	struct ptp_clock_caps caps = {
+		.max_adj		= ptp->info->max_adj,
+		.n_alarm		= ptp->info->n_alarm,
+		.n_ext_ts		= ptp->info->n_ext_ts,
+		.n_per_out		= ptp->info->n_per_out,
+		.pps			= ptp->info->pps,
+		.n_pins			= ptp->info->n_pins,
+		.cross_timestamping	= ptp->info->getcrosststamp != NULL,
+		.adjust_phase		= ptp->info->adjphase != NULL &&
+					  ptp->info->getmaxphase != NULL,
+	};
+
+	if (caps.adjust_phase)
+		caps.max_phase_adj = ptp->info->getmaxphase(ptp->info);
+
+	return copy_to_user(arg, &caps, sizeof(caps)) ? -EFAULT : 0;
+}
+
+static long ptp_extts_request(struct ptp_clock *ptp, unsigned int cmd, void __user *arg)
+{
+	struct ptp_clock_request req = { .type = PTP_CLK_REQ_EXTTS };
+	struct ptp_clock_info *ops = ptp->info;
+	unsigned int supported_extts_flags;
+
+	if (copy_from_user(&req.extts, arg, sizeof(req.extts)))
+		return -EFAULT;
+
+	if (cmd == PTP_EXTTS_REQUEST2) {
+		/* Tell the drivers to check the flags carefully. */
+		req.extts.flags |= PTP_STRICT_FLAGS;
+		/* Make sure no reserved bit is set. */
+		if ((req.extts.flags & ~PTP_EXTTS_VALID_FLAGS) ||
+		    req.extts.rsv[0] || req.extts.rsv[1])
+			return -EINVAL;
+
+		/* Ensure one of the rising/falling edge bits is set. */
+		if ((req.extts.flags & PTP_ENABLE_FEATURE) &&
+		    (req.extts.flags & PTP_EXTTS_EDGES) == 0)
+			return -EINVAL;
+	} else {
+		req.extts.flags &= PTP_EXTTS_V1_VALID_FLAGS;
+		memset(req.extts.rsv, 0, sizeof(req.extts.rsv));
+	}
+
+	if (req.extts.index >= ops->n_ext_ts)
+		return -EINVAL;
+
+	supported_extts_flags = ptp->info->supported_extts_flags;
+	/* The PTP_ENABLE_FEATURE flag is always supported. */
+	supported_extts_flags |= PTP_ENABLE_FEATURE;
+	/* If the driver does not support strictly checking flags, the
+	 * PTP_RISING_EDGE and PTP_FALLING_EDGE flags are merely hints
+	 * which are not enforced.
+	 */
+	if (!(supported_extts_flags & PTP_STRICT_FLAGS))
+		supported_extts_flags |= PTP_EXTTS_EDGES;
+	/* Reject unsupported flags */
+	if (req.extts.flags & ~supported_extts_flags)
+		return -EOPNOTSUPP;
+
+	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &ptp->pincfg_mux)
+		return ops->enable(ops, &req, req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0);
+}
+
+static long ptp_perout_request(struct ptp_clock *ptp, unsigned int cmd, void __user *arg)
+{
+	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
+	struct ptp_perout_request *perout = &req.perout;
+	struct ptp_clock_info *ops = ptp->info;
+
+	if (copy_from_user(perout, arg, sizeof(*perout)))
+		return -EFAULT;
+
+	if (cmd == PTP_PEROUT_REQUEST2) {
+		if (perout->flags & ~PTP_PEROUT_VALID_FLAGS)
+			return -EINVAL;
+
+		/*
+		 * The "on" field has undefined meaning if
+		 * PTP_PEROUT_DUTY_CYCLE isn't set, we must still treat it
+		 * as reserved, which must be set to zero.
+		 */
+		if (!(perout->flags & PTP_PEROUT_DUTY_CYCLE) &&
+		    !mem_is_zero(perout->rsv, sizeof(perout->rsv)))
+			return -EINVAL;
+
+		if (perout->flags & PTP_PEROUT_DUTY_CYCLE) {
+			/* The duty cycle must be subunitary. */
+			if (perout->on.sec > perout->period.sec ||
+			    (perout->on.sec == perout->period.sec &&
+			     perout->on.nsec > perout->period.nsec))
+				return -ERANGE;
+		}
+
+		if (perout->flags & PTP_PEROUT_PHASE) {
+			/*
+			 * The phase should be specified modulo the period,
+			 * therefore anything equal or larger than 1 period
+			 * is invalid.
+			 */
+			if (perout->phase.sec > perout->period.sec ||
+			    (perout->phase.sec == perout->period.sec &&
+			     perout->phase.nsec >= perout->period.nsec))
+				return -ERANGE;
+		}
+	} else {
+		perout->flags &= PTP_PEROUT_V1_VALID_FLAGS;
+		memset(perout->rsv, 0, sizeof(perout->rsv));
+	}
+
+	if (perout->index >= ops->n_per_out)
+		return -EINVAL;
+	if (perout->flags & ~ops->supported_perout_flags)
+		return -EOPNOTSUPP;
+
+	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &ptp->pincfg_mux)
+		return ops->enable(ops, &req, perout->period.sec || perout->period.nsec);
+}
+
+static long ptp_enable_pps(struct ptp_clock *ptp, bool enable)
+{
+	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
+	struct ptp_clock_info *ops = ptp->info;
+
+	if (!capable(CAP_SYS_TIME))
+		return -EPERM;
+
+	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &ptp->pincfg_mux)
+		return ops->enable(ops, &req, enable);
+}
+
+static long ptp_sys_offset_precise(struct ptp_clock *ptp, void __user *arg)
 {
-	struct ptp_clock *ptp =
-		container_of(pccontext->clk, struct ptp_clock, clock);
-	unsigned int i, pin_index, supported_extts_flags;
-	struct ptp_sys_offset_extended *extoff = NULL;
 	struct ptp_sys_offset_precise precise_offset;
 	struct system_device_crosststamp xtstamp;
-	struct ptp_clock_info *ops = ptp->info;
-	struct ptp_sys_offset *sysoff = NULL;
-	struct timestamp_event_queue *tsevq;
+	struct timespec64 ts;
+	int err;
+
+	if (!ptp->info->getcrosststamp)
+		return -EOPNOTSUPP;
+
+	err = ptp->info->getcrosststamp(ptp->info, &xtstamp);
+	if (err)
+		return err;
+
+	memset(&precise_offset, 0, sizeof(precise_offset));
+	ts = ktime_to_timespec64(xtstamp.device);
+	precise_offset.device.sec = ts.tv_sec;
+	precise_offset.device.nsec = ts.tv_nsec;
+	ts = ktime_to_timespec64(xtstamp.sys_realtime);
+	precise_offset.sys_realtime.sec = ts.tv_sec;
+	precise_offset.sys_realtime.nsec = ts.tv_nsec;
+	ts = ktime_to_timespec64(xtstamp.sys_monoraw);
+	precise_offset.sys_monoraw.sec = ts.tv_sec;
+	precise_offset.sys_monoraw.nsec = ts.tv_nsec;
+
+	return copy_to_user(arg, &precise_offset, sizeof(precise_offset)) ? -EFAULT : 0;
+}
+
+static long ptp_sys_offset_extended(struct ptp_clock *ptp, void __user *arg)
+{
+	struct ptp_sys_offset_extended *extoff __free(kfree) = NULL;
 	struct ptp_system_timestamp sts;
-	struct ptp_clock_request req;
-	struct ptp_clock_caps caps;
+
+	if (!ptp->info->gettimex64)
+		return -EOPNOTSUPP;
+
+	extoff = memdup_user(arg, sizeof(*extoff));
+	if (IS_ERR(extoff))
+		return PTR_ERR(extoff);
+
+	if (extoff->n_samples > PTP_MAX_SAMPLES ||
+	    extoff->rsv[0] || extoff->rsv[1] ||
+	    (extoff->clockid != CLOCK_REALTIME &&
+	     extoff->clockid != CLOCK_MONOTONIC &&
+	     extoff->clockid != CLOCK_MONOTONIC_RAW))
+		return -EINVAL;
+
+	sts.clockid = extoff->clockid;
+	for (unsigned int i = 0; i < extoff->n_samples; i++) {
+		struct timespec64 ts;
+		int err;
+
+		err = ptp->info->gettimex64(ptp->info, &ts, &sts);
+		if (err)
+			return err;
+		extoff->ts[i][0].sec = sts.pre_ts.tv_sec;
+		extoff->ts[i][0].nsec = sts.pre_ts.tv_nsec;
+		extoff->ts[i][1].sec = ts.tv_sec;
+		extoff->ts[i][1].nsec = ts.tv_nsec;
+		extoff->ts[i][2].sec = sts.post_ts.tv_sec;
+		extoff->ts[i][2].nsec = sts.post_ts.tv_nsec;
+	}
+
+	return copy_to_user(arg, extoff, sizeof(*extoff)) ? -EFAULT : 0;
+}
+
+static long ptp_sys_offset(struct ptp_clock *ptp, void __user *arg)
+{
+	struct ptp_sys_offset *sysoff __free(kfree) = NULL;
 	struct ptp_clock_time *pct;
-	struct ptp_pin_desc pd;
 	struct timespec64 ts;
-	int enable, err = 0;
+
+	sysoff = memdup_user(arg, sizeof(*sysoff));
+	if (IS_ERR(sysoff))
+		return PTR_ERR(sysoff);
+
+	if (sysoff->n_samples > PTP_MAX_SAMPLES)
+		return -EINVAL;
+
+	pct = &sysoff->ts[0];
+	for (unsigned int i = 0; i < sysoff->n_samples; i++) {
+		struct ptp_clock_info *ops = ptp->info;
+		int err;
+
+		ktime_get_real_ts64(&ts);
+		pct->sec = ts.tv_sec;
+		pct->nsec = ts.tv_nsec;
+		pct++;
+		if (ops->gettimex64)
+			err = ops->gettimex64(ops, &ts, NULL);
+		else
+			err = ops->gettime64(ops, &ts);
+		if (err)
+			return err;
+		pct->sec = ts.tv_sec;
+		pct->nsec = ts.tv_nsec;
+		pct++;
+	}
+	ktime_get_real_ts64(&ts);
+	pct->sec = ts.tv_sec;
+	pct->nsec = ts.tv_nsec;
+
+	return copy_to_user(arg, sysoff, sizeof(*sysoff)) ? -EFAULT : 0;
+}
+
+static long ptp_pin_getfunc(struct ptp_clock *ptp, unsigned int cmd, void __user *arg)
+{
+	struct ptp_clock_info *ops = ptp->info;
+	struct ptp_pin_desc pd;
+
+	if (copy_from_user(&pd, arg, sizeof(pd)))
+		return -EFAULT;
+
+	if (cmd == PTP_PIN_GETFUNC2 && !mem_is_zero(pd.rsv, sizeof(pd.rsv)))
+		return -EINVAL;
+
+	if (pd.index >= ops->n_pins)
+		return -EINVAL;
+
+	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &ptp->pincfg_mux)
+		pd = ops->pin_config[array_index_nospec(pd.index, ops->n_pins)];
+
+	return copy_to_user(arg, &pd, sizeof(pd)) ? -EFAULT : 0;
+}
+
+static long ptp_pin_setfunc(struct ptp_clock *ptp, unsigned int cmd, void __user *arg)
+{
+	struct ptp_clock_info *ops = ptp->info;
+	struct ptp_pin_desc pd;
+	unsigned int pin_index;
+
+	if (copy_from_user(&pd, arg, sizeof(pd)))
+		return -EFAULT;
+
+	if (cmd == PTP_PIN_SETFUNC2 && !mem_is_zero(pd.rsv, sizeof(pd.rsv)))
+		return -EINVAL;
+
+	if (pd.index >= ops->n_pins)
+		return -EINVAL;
+
+	pin_index = array_index_nospec(pd.index, ops->n_pins);
+	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &ptp->pincfg_mux)
+		return ptp_set_pinfunc(ptp, pin_index, pd.func, pd.chan);
+}
+
+static long ptp_mask_clear_all(struct timestamp_event_queue *tsevq)
+{
+	bitmap_clear(tsevq->mask, 0, PTP_MAX_CHANNELS);
+	return 0;
+}
+
+static long ptp_mask_en_single(struct timestamp_event_queue *tsevq, void __user *arg)
+{
+	unsigned int channel;
+
+	if (copy_from_user(&channel, arg, sizeof(channel)))
+		return -EFAULT;
+	if (channel >= PTP_MAX_CHANNELS)
+		return -EFAULT;
+	set_bit(channel, tsevq->mask);
+	return 0;
+}
+
+long ptp_ioctl(struct posix_clock_context *pccontext, unsigned int cmd,
+	       unsigned long arg)
+{
+	struct ptp_clock *ptp = container_of(pccontext->clk, struct ptp_clock, clock);
+	void __user *argptr;
 
 	if (in_compat_syscall() && cmd != PTP_ENABLE_PPS && cmd != PTP_ENABLE_PPS2)
 		arg = (unsigned long)compat_ptr(arg);
-
-	tsevq = pccontext->private_clkdata;
+	argptr = (void __force __user *)arg;
 
 	switch (cmd) {
-
 	case PTP_CLOCK_GETCAPS:
 	case PTP_CLOCK_GETCAPS2:
-		memset(&caps, 0, sizeof(caps));
-
-		caps.max_adj = ptp->info->max_adj;
-		caps.n_alarm = ptp->info->n_alarm;
-		caps.n_ext_ts = ptp->info->n_ext_ts;
-		caps.n_per_out = ptp->info->n_per_out;
-		caps.pps = ptp->info->pps;
-		caps.n_pins = ptp->info->n_pins;
-		caps.cross_timestamping = ptp->info->getcrosststamp != NULL;
-		caps.adjust_phase = ptp->info->adjphase != NULL &&
-				    ptp->info->getmaxphase != NULL;
-		if (caps.adjust_phase)
-			caps.max_phase_adj = ptp->info->getmaxphase(ptp->info);
-		if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
-			err = -EFAULT;
-		break;
+		return ptp_clock_getcaps(ptp, argptr);
 
 	case PTP_EXTTS_REQUEST:
 	case PTP_EXTTS_REQUEST2:
-		if ((pccontext->fp->f_mode & FMODE_WRITE) == 0) {
-			err = -EACCES;
-			break;
-		}
-		memset(&req, 0, sizeof(req));
-
-		if (copy_from_user(&req.extts, (void __user *)arg,
-				   sizeof(req.extts))) {
-			err = -EFAULT;
-			break;
-		}
-		if (cmd == PTP_EXTTS_REQUEST2) {
-			/* Tell the drivers to check the flags carefully. */
-			req.extts.flags |= PTP_STRICT_FLAGS;
-			/* Make sure no reserved bit is set. */
-			if ((req.extts.flags & ~PTP_EXTTS_VALID_FLAGS) ||
-			    req.extts.rsv[0] || req.extts.rsv[1]) {
-				err = -EINVAL;
-				break;
-			}
-			/* Ensure one of the rising/falling edge bits is set. */
-			if ((req.extts.flags & PTP_ENABLE_FEATURE) &&
-			    (req.extts.flags & PTP_EXTTS_EDGES) == 0) {
-				err = -EINVAL;
-				break;
-			}
-		} else if (cmd == PTP_EXTTS_REQUEST) {
-			req.extts.flags &= PTP_EXTTS_V1_VALID_FLAGS;
-			req.extts.rsv[0] = 0;
-			req.extts.rsv[1] = 0;
-		}
-		if (req.extts.index >= ops->n_ext_ts) {
-			err = -EINVAL;
-			break;
-		}
-		supported_extts_flags = ptp->info->supported_extts_flags;
-		/* The PTP_ENABLE_FEATURE flag is always supported. */
-		supported_extts_flags |= PTP_ENABLE_FEATURE;
-		/* If the driver does not support strictly checking flags, the
-		 * PTP_RISING_EDGE and PTP_FALLING_EDGE flags are merely
-		 * hints which are not enforced.
-		 */
-		if (!(supported_extts_flags & PTP_STRICT_FLAGS))
-			supported_extts_flags |= PTP_EXTTS_EDGES;
-		/* Reject unsupported flags */
-		if (req.extts.flags & ~supported_extts_flags)
-			return -EOPNOTSUPP;
-		req.type = PTP_CLK_REQ_EXTTS;
-		enable = req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0;
-		if (mutex_lock_interruptible(&ptp->pincfg_mux))
-			return -ERESTARTSYS;
-		err = ops->enable(ops, &req, enable);
-		mutex_unlock(&ptp->pincfg_mux);
-		break;
+		if ((pccontext->fp->f_mode & FMODE_WRITE) == 0)
+			return -EACCES;
+		return ptp_extts_request(ptp, cmd, argptr);
 
 	case PTP_PEROUT_REQUEST:
 	case PTP_PEROUT_REQUEST2:
-		if ((pccontext->fp->f_mode & FMODE_WRITE) == 0) {
-			err = -EACCES;
-			break;
-		}
-		memset(&req, 0, sizeof(req));
-
-		if (copy_from_user(&req.perout, (void __user *)arg,
-				   sizeof(req.perout))) {
-			err = -EFAULT;
-			break;
-		}
-		if (cmd == PTP_PEROUT_REQUEST2) {
-			struct ptp_perout_request *perout = &req.perout;
-
-			if (perout->flags & ~PTP_PEROUT_VALID_FLAGS) {
-				err = -EINVAL;
-				break;
-			}
-			/*
-			 * The "on" field has undefined meaning if
-			 * PTP_PEROUT_DUTY_CYCLE isn't set, we must still treat
-			 * it as reserved, which must be set to zero.
-			 */
-			if (!(perout->flags & PTP_PEROUT_DUTY_CYCLE) &&
-			    (perout->rsv[0] || perout->rsv[1] ||
-			     perout->rsv[2] || perout->rsv[3])) {
-				err = -EINVAL;
-				break;
-			}
-			if (perout->flags & PTP_PEROUT_DUTY_CYCLE) {
-				/* The duty cycle must be subunitary. */
-				if (perout->on.sec > perout->period.sec ||
-				    (perout->on.sec == perout->period.sec &&
-				     perout->on.nsec > perout->period.nsec)) {
-					err = -ERANGE;
-					break;
-				}
-			}
-			if (perout->flags & PTP_PEROUT_PHASE) {
-				/*
-				 * The phase should be specified modulo the
-				 * period, therefore anything equal or larger
-				 * than 1 period is invalid.
-				 */
-				if (perout->phase.sec > perout->period.sec ||
-				    (perout->phase.sec == perout->period.sec &&
-				     perout->phase.nsec >= perout->period.nsec)) {
-					err = -ERANGE;
-					break;
-				}
-			}
-		} else if (cmd == PTP_PEROUT_REQUEST) {
-			req.perout.flags &= PTP_PEROUT_V1_VALID_FLAGS;
-			req.perout.rsv[0] = 0;
-			req.perout.rsv[1] = 0;
-			req.perout.rsv[2] = 0;
-			req.perout.rsv[3] = 0;
-		}
-		if (req.perout.index >= ops->n_per_out) {
-			err = -EINVAL;
-			break;
-		}
-		if (req.perout.flags & ~ptp->info->supported_perout_flags)
-			return -EOPNOTSUPP;
-		req.type = PTP_CLK_REQ_PEROUT;
-		enable = req.perout.period.sec || req.perout.period.nsec;
-		if (mutex_lock_interruptible(&ptp->pincfg_mux))
-			return -ERESTARTSYS;
-		err = ops->enable(ops, &req, enable);
-		mutex_unlock(&ptp->pincfg_mux);
-		break;
+		if ((pccontext->fp->f_mode & FMODE_WRITE) == 0)
+			return -EACCES;
+		return ptp_perout_request(ptp, cmd, argptr);
 
 	case PTP_ENABLE_PPS:
 	case PTP_ENABLE_PPS2:
-		if ((pccontext->fp->f_mode & FMODE_WRITE) == 0) {
-			err = -EACCES;
-			break;
-		}
-		memset(&req, 0, sizeof(req));
-
-		if (!capable(CAP_SYS_TIME))
-			return -EPERM;
-		req.type = PTP_CLK_REQ_PPS;
-		enable = arg ? 1 : 0;
-		if (mutex_lock_interruptible(&ptp->pincfg_mux))
-			return -ERESTARTSYS;
-		err = ops->enable(ops, &req, enable);
-		mutex_unlock(&ptp->pincfg_mux);
-		break;
+		if ((pccontext->fp->f_mode & FMODE_WRITE) == 0)
+			return -EACCES;
+		return ptp_enable_pps(ptp, !!arg);
 
 	case PTP_SYS_OFFSET_PRECISE:
 	case PTP_SYS_OFFSET_PRECISE2:
-		if (!ptp->info->getcrosststamp) {
-			err = -EOPNOTSUPP;
-			break;
-		}
-		err = ptp->info->getcrosststamp(ptp->info, &xtstamp);
-		if (err)
-			break;
-
-		memset(&precise_offset, 0, sizeof(precise_offset));
-		ts = ktime_to_timespec64(xtstamp.device);
-		precise_offset.device.sec = ts.tv_sec;
-		precise_offset.device.nsec = ts.tv_nsec;
-		ts = ktime_to_timespec64(xtstamp.sys_realtime);
-		precise_offset.sys_realtime.sec = ts.tv_sec;
-		precise_offset.sys_realtime.nsec = ts.tv_nsec;
-		ts = ktime_to_timespec64(xtstamp.sys_monoraw);
-		precise_offset.sys_monoraw.sec = ts.tv_sec;
-		precise_offset.sys_monoraw.nsec = ts.tv_nsec;
-		if (copy_to_user((void __user *)arg, &precise_offset,
-				 sizeof(precise_offset)))
-			err = -EFAULT;
-		break;
+		return ptp_sys_offset_precise(ptp, argptr);
 
 	case PTP_SYS_OFFSET_EXTENDED:
 	case PTP_SYS_OFFSET_EXTENDED2:
-		if (!ptp->info->gettimex64) {
-			err = -EOPNOTSUPP;
-			break;
-		}
-		extoff = memdup_user((void __user *)arg, sizeof(*extoff));
-		if (IS_ERR(extoff)) {
-			err = PTR_ERR(extoff);
-			extoff = NULL;
-			break;
-		}
-		if (extoff->n_samples > PTP_MAX_SAMPLES ||
-		    extoff->rsv[0] || extoff->rsv[1] ||
-		    (extoff->clockid != CLOCK_REALTIME &&
-		     extoff->clockid != CLOCK_MONOTONIC &&
-		     extoff->clockid != CLOCK_MONOTONIC_RAW)) {
-			err = -EINVAL;
-			break;
-		}
-		sts.clockid = extoff->clockid;
-		for (i = 0; i < extoff->n_samples; i++) {
-			err = ptp->info->gettimex64(ptp->info, &ts, &sts);
-			if (err)
-				goto out;
-			extoff->ts[i][0].sec = sts.pre_ts.tv_sec;
-			extoff->ts[i][0].nsec = sts.pre_ts.tv_nsec;
-			extoff->ts[i][1].sec = ts.tv_sec;
-			extoff->ts[i][1].nsec = ts.tv_nsec;
-			extoff->ts[i][2].sec = sts.post_ts.tv_sec;
-			extoff->ts[i][2].nsec = sts.post_ts.tv_nsec;
-		}
-		if (copy_to_user((void __user *)arg, extoff, sizeof(*extoff)))
-			err = -EFAULT;
-		break;
+		return ptp_sys_offset_extended(ptp, argptr);
 
 	case PTP_SYS_OFFSET:
 	case PTP_SYS_OFFSET2:
-		sysoff = memdup_user((void __user *)arg, sizeof(*sysoff));
-		if (IS_ERR(sysoff)) {
-			err = PTR_ERR(sysoff);
-			sysoff = NULL;
-			break;
-		}
-		if (sysoff->n_samples > PTP_MAX_SAMPLES) {
-			err = -EINVAL;
-			break;
-		}
-		pct = &sysoff->ts[0];
-		for (i = 0; i < sysoff->n_samples; i++) {
-			ktime_get_real_ts64(&ts);
-			pct->sec = ts.tv_sec;
-			pct->nsec = ts.tv_nsec;
-			pct++;
-			if (ops->gettimex64)
-				err = ops->gettimex64(ops, &ts, NULL);
-			else
-				err = ops->gettime64(ops, &ts);
-			if (err)
-				goto out;
-			pct->sec = ts.tv_sec;
-			pct->nsec = ts.tv_nsec;
-			pct++;
-		}
-		ktime_get_real_ts64(&ts);
-		pct->sec = ts.tv_sec;
-		pct->nsec = ts.tv_nsec;
-		if (copy_to_user((void __user *)arg, sysoff, sizeof(*sysoff)))
-			err = -EFAULT;
-		break;
+		return ptp_sys_offset(ptp, argptr);
 
 	case PTP_PIN_GETFUNC:
 	case PTP_PIN_GETFUNC2:
-		if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
-			err = -EFAULT;
-			break;
-		}
-		if ((pd.rsv[0] || pd.rsv[1] || pd.rsv[2]
-				|| pd.rsv[3] || pd.rsv[4])
-			&& cmd == PTP_PIN_GETFUNC2) {
-			err = -EINVAL;
-			break;
-		} else if (cmd == PTP_PIN_GETFUNC) {
-			pd.rsv[0] = 0;
-			pd.rsv[1] = 0;
-			pd.rsv[2] = 0;
-			pd.rsv[3] = 0;
-			pd.rsv[4] = 0;
-		}
-		pin_index = pd.index;
-		if (pin_index >= ops->n_pins) {
-			err = -EINVAL;
-			break;
-		}
-		pin_index = array_index_nospec(pin_index, ops->n_pins);
-		if (mutex_lock_interruptible(&ptp->pincfg_mux))
-			return -ERESTARTSYS;
-		pd = ops->pin_config[pin_index];
-		mutex_unlock(&ptp->pincfg_mux);
-		if (!err && copy_to_user((void __user *)arg, &pd, sizeof(pd)))
-			err = -EFAULT;
-		break;
+		return ptp_pin_getfunc(ptp, cmd, argptr);
 
 	case PTP_PIN_SETFUNC:
 	case PTP_PIN_SETFUNC2:
-		if ((pccontext->fp->f_mode & FMODE_WRITE) == 0) {
-			err = -EACCES;
-			break;
-		}
-		if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
-			err = -EFAULT;
-			break;
-		}
-		if ((pd.rsv[0] || pd.rsv[1] || pd.rsv[2]
-				|| pd.rsv[3] || pd.rsv[4])
-			&& cmd == PTP_PIN_SETFUNC2) {
-			err = -EINVAL;
-			break;
-		} else if (cmd == PTP_PIN_SETFUNC) {
-			pd.rsv[0] = 0;
-			pd.rsv[1] = 0;
-			pd.rsv[2] = 0;
-			pd.rsv[3] = 0;
-			pd.rsv[4] = 0;
-		}
-		pin_index = pd.index;
-		if (pin_index >= ops->n_pins) {
-			err = -EINVAL;
-			break;
-		}
-		pin_index = array_index_nospec(pin_index, ops->n_pins);
-		if (mutex_lock_interruptible(&ptp->pincfg_mux))
-			return -ERESTARTSYS;
-		err = ptp_set_pinfunc(ptp, pin_index, pd.func, pd.chan);
-		mutex_unlock(&ptp->pincfg_mux);
-		break;
+		if ((pccontext->fp->f_mode & FMODE_WRITE) == 0)
+			return -EACCES;
+		return ptp_pin_setfunc(ptp, cmd, argptr);
 
 	case PTP_MASK_CLEAR_ALL:
-		bitmap_clear(tsevq->mask, 0, PTP_MAX_CHANNELS);
-		break;
+		return ptp_mask_clear_all(pccontext->private_clkdata);
 
 	case PTP_MASK_EN_SINGLE:
-		if (copy_from_user(&i, (void __user *)arg, sizeof(i))) {
-			err = -EFAULT;
-			break;
-		}
-		if (i >= PTP_MAX_CHANNELS) {
-			err = -EFAULT;
-			break;
-		}
-		set_bit(i, tsevq->mask);
-		break;
+		return ptp_mask_en_single(pccontext->private_clkdata, argptr);
 
 	default:
-		err = -ENOTTY;
-		break;
+		return -ENOTTY;
 	}
-
-out:
-	kfree(extoff);
-	kfree(sysoff);
-	return err;
 }
 
 __poll_t ptp_poll(struct posix_clock_context *pccontext, struct file *fp,
@@ -562,71 +535,46 @@ __poll_t ptp_poll(struct posix_clock_context *pccontext, struct file *fp,
 ssize_t ptp_read(struct posix_clock_context *pccontext, uint rdflags,
 		 char __user *buf, size_t cnt)
 {
-	struct ptp_clock *ptp =
-		container_of(pccontext->clk, struct ptp_clock, clock);
+	struct ptp_clock *ptp =	container_of(pccontext->clk, struct ptp_clock, clock);
 	struct timestamp_event_queue *queue;
 	struct ptp_extts_event *event;
-	unsigned long flags;
-	size_t qcnt, i;
-	int result;
+	ssize_t result;
 
 	queue = pccontext->private_clkdata;
-	if (!queue) {
-		result = -EINVAL;
-		goto exit;
-	}
+	if (!queue)
+		return -EINVAL;
 
-	if (cnt % sizeof(struct ptp_extts_event) != 0) {
-		result = -EINVAL;
-		goto exit;
-	}
+	if (cnt % sizeof(*event) != 0)
+		return -EINVAL;
 
 	if (cnt > EXTTS_BUFSIZE)
 		cnt = EXTTS_BUFSIZE;
 
-	cnt = cnt / sizeof(struct ptp_extts_event);
-
-	if (wait_event_interruptible(ptp->tsev_wq,
-				     ptp->defunct || queue_cnt(queue))) {
+	if (wait_event_interruptible(ptp->tsev_wq, ptp->defunct || queue_cnt(queue)))
 		return -ERESTARTSYS;
-	}
 
-	if (ptp->defunct) {
-		result = -ENODEV;
-		goto exit;
-	}
+	if (ptp->defunct)
+		return -ENODEV;
 
 	event = kmalloc(EXTTS_BUFSIZE, GFP_KERNEL);
-	if (!event) {
-		result = -ENOMEM;
-		goto exit;
-	}
+	if (!event)
+		return -ENOMEM;
 
-	spin_lock_irqsave(&queue->lock, flags);
+	scoped_guard(spinlock_irq, &queue->lock) {
+		size_t qcnt = min((size_t)queue_cnt(queue), cnt / sizeof(*event));
 
-	qcnt = queue_cnt(queue);
-
-	if (cnt > qcnt)
-		cnt = qcnt;
-
-	for (i = 0; i < cnt; i++) {
-		event[i] = queue->buf[queue->head];
-		/* Paired with READ_ONCE() in queue_cnt() */
-		WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
+		for (size_t i = 0; i < qcnt; i++) {
+			event[i] = queue->buf[queue->head];
+			/* Paired with READ_ONCE() in queue_cnt() */
+			WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
+		}
+		cnt = qcnt * sizeof(*event);
 	}
 
-	spin_unlock_irqrestore(&queue->lock, flags);
-
-	cnt = cnt * sizeof(struct ptp_extts_event);
-
 	result = cnt;
-	if (copy_to_user(buf, event, cnt)) {
+	if (copy_to_user(buf, event, cnt))
 		result = -EFAULT;
-		goto free_event;
-	}
 
-free_event:
 	kfree(event);
-exit:
 	return result;
 }