2019-08-14 07:49:56

by Felipe Balbi

[permalink] [raw]
Subject: [PATCH 1/2] PTP: introduce new versions of IOCTLs

The current version of the IOCTL have a small problem which prevents us
from extending the API by making use of reserved fields. In these new
IOCTLs, we are now making sure that flags and rsv fields are zero which
will allow us to extend the API in the future.

Signed-off-by: Felipe Balbi <[email protected]>
---
drivers/ptp/ptp_chardev.c | 58 ++++++++++++++++++++++++++++++++--
include/uapi/linux/ptp_clock.h | 12 +++++++
2 files changed, 68 insertions(+), 2 deletions(-)

diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
index 18ffe449efdf..204212fc3f8c 100644
--- a/drivers/ptp/ptp_chardev.c
+++ b/drivers/ptp/ptp_chardev.c
@@ -123,9 +123,11 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
struct timespec64 ts;
int enable, err = 0;

+ memset(&req, 0, sizeof(req));
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;
@@ -139,11 +141,22 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
break;

case PTP_EXTTS_REQUEST:
+ case PTP_EXTTS_REQUEST2:
if (copy_from_user(&req.extts, (void __user *)arg,
sizeof(req.extts))) {
err = -EFAULT;
break;
}
+ if ((req.extts.flags || req.extts.rsv[0] || req.extts.rsv[1])
+ && cmd == PTP_EXTTS_REQUEST2) {
+ err = -EINVAL;
+ break;
+ } else if (cmd == PTP_EXTTS_REQUEST) {
+ req.extts.flags = 0;
+ req.extts.rsv[0] = 0;
+ req.extts.rsv[1] = 0;
+ }
+
if (req.extts.index >= ops->n_ext_ts) {
err = -EINVAL;
break;
@@ -154,11 +167,24 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
break;

case PTP_PEROUT_REQUEST:
+ case PTP_PEROUT_REQUEST2:
if (copy_from_user(&req.perout, (void __user *)arg,
sizeof(req.perout))) {
err = -EFAULT;
break;
}
+ if ((req.perout.flags || req.perout.rsv[0] || req.perout.rsv[1]
+ || req.perout.rsv[2] || req.perout.rsv[3])
+ && cmd == PTP_PEROUT_REQUEST2) {
+ err = -EINVAL;
+ break;
+ } else if (cmd == PTP_PEROUT_REQUEST) {
+ req.perout.flags = 0;
+ 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;
@@ -169,6 +195,7 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
break;

case PTP_ENABLE_PPS:
+ case PTP_ENABLE_PPS2:
if (!capable(CAP_SYS_TIME))
return -EPERM;
req.type = PTP_CLK_REQ_PPS;
@@ -177,6 +204,7 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
break;

case PTP_SYS_OFFSET_PRECISE:
+ case PTP_SYS_OFFSET_PRECISE2:
if (!ptp->info->getcrosststamp) {
err = -EOPNOTSUPP;
break;
@@ -201,6 +229,7 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
break;

case PTP_SYS_OFFSET_EXTENDED:
+ case PTP_SYS_OFFSET_EXTENDED2:
if (!ptp->info->gettimex64) {
err = -EOPNOTSUPP;
break;
@@ -232,6 +261,7 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
break;

case PTP_SYS_OFFSET:
+ case PTP_SYS_OFFSET2:
sysoff = memdup_user((void __user *)arg, sizeof(*sysoff));
if (IS_ERR(sysoff)) {
err = PTR_ERR(sysoff);
@@ -265,11 +295,23 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
err = -EFAULT;
break;

- 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;
@@ -284,11 +326,23 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
err = -EFAULT;
break;

- case PTP_PIN_SETFUNC:
+ case PTP_PIN_SETFUNC2:
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;
diff --git a/include/uapi/linux/ptp_clock.h b/include/uapi/linux/ptp_clock.h
index 1bc794ad957a..039cd62ec706 100644
--- a/include/uapi/linux/ptp_clock.h
+++ b/include/uapi/linux/ptp_clock.h
@@ -149,6 +149,18 @@ struct ptp_pin_desc {
#define PTP_SYS_OFFSET_EXTENDED \
_IOWR(PTP_CLK_MAGIC, 9, struct ptp_sys_offset_extended)

+#define PTP_CLOCK_GETCAPS2 _IOR(PTP_CLK_MAGIC, 10, struct ptp_clock_caps)
+#define PTP_EXTTS_REQUEST2 _IOW(PTP_CLK_MAGIC, 11, struct ptp_extts_request)
+#define PTP_PEROUT_REQUEST2 _IOW(PTP_CLK_MAGIC, 12, struct ptp_perout_request)
+#define PTP_ENABLE_PPS2 _IOW(PTP_CLK_MAGIC, 13, int)
+#define PTP_SYS_OFFSET2 _IOW(PTP_CLK_MAGIC, 14, struct ptp_sys_offset)
+#define PTP_PIN_GETFUNC2 _IOWR(PTP_CLK_MAGIC, 15, struct ptp_pin_desc)
+#define PTP_PIN_SETFUNC2 _IOW(PTP_CLK_MAGIC, 16, struct ptp_pin_desc)
+#define PTP_SYS_OFFSET_PRECISE2 \
+ _IOWR(PTP_CLK_MAGIC, 17, struct ptp_sys_offset_precise)
+#define PTP_SYS_OFFSET_EXTENDED2 \
+ _IOWR(PTP_CLK_MAGIC, 18, struct ptp_sys_offset_extended)
+
struct ptp_extts_event {
struct ptp_clock_time t; /* Time event occured. */
unsigned int index; /* Which channel produced the event. */
--
2.22.0


2019-08-17 16:00:33

by Richard Cochran

[permalink] [raw]
Subject: Re: [PATCH 1/2] PTP: introduce new versions of IOCTLs

On Wed, Aug 14, 2019 at 10:47:11AM +0300, Felipe Balbi wrote:
> The current version of the IOCTL have a small problem which prevents us
> from extending the API by making use of reserved fields. In these new
> IOCTLs, we are now making sure that flags and rsv fields are zero which
> will allow us to extend the API in the future.
>
> Signed-off-by: Felipe Balbi <[email protected]>
> ---
> drivers/ptp/ptp_chardev.c | 58 ++++++++++++++++++++++++++++++++--
> include/uapi/linux/ptp_clock.h | 12 +++++++
> 2 files changed, 68 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
> index 18ffe449efdf..204212fc3f8c 100644
> --- a/drivers/ptp/ptp_chardev.c
> +++ b/drivers/ptp/ptp_chardev.c
> @@ -123,9 +123,11 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
> struct timespec64 ts;
> int enable, err = 0;
>
> + memset(&req, 0, sizeof(req));

Nit: please leave a blank line between memset() and switch/case.

> 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;

Reviewed-by: Richard Cochran <[email protected]>

2019-08-17 16:18:34

by Joe Perches

[permalink] [raw]
Subject: Re: [PATCH 1/2] PTP: introduce new versions of IOCTLs

On Sat, 2019-08-17 at 08:59 -0700, Richard Cochran wrote:
> On Wed, Aug 14, 2019 at 10:47:11AM +0300, Felipe Balbi wrote:
> > The current version of the IOCTL have a small problem which prevents us
> > from extending the API by making use of reserved fields. In these new
> > IOCTLs, we are now making sure that flags and rsv fields are zero which
> > will allow us to extend the API in the future.
> >
> > Signed-off-by: Felipe Balbi <[email protected]>
> > ---
> > drivers/ptp/ptp_chardev.c | 58 ++++++++++++++++++++++++++++++++--
> > include/uapi/linux/ptp_clock.h | 12 +++++++
> > 2 files changed, 68 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
[]
> > @@ -123,9 +123,11 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
> > struct timespec64 ts;
> > int enable, err = 0;
> >
> > + memset(&req, 0, sizeof(req));
>
> Nit: please leave a blank line between memset() and switch/case.

or just initialize the declaration of req with = {}

Is there a case where this initialization is
unnecessary such that it impacts performance
given the use in ptp_ioctl?

caps for instance is memset to zero only in
PTP_CLOCK_GETCAP

req is used in only 3 of the case blocks.

case PTP_EXTTS_REQUEST:
case PTP_PEROUT_REQUEST:
case PTP_ENABLE_PPS:

Maybe it would be better to move the memset(&req...)
into each of the case blocks.

> > 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;
>
> Reviewed-by: Richard Cochran <[email protected]>
>

2019-08-18 20:12:57

by Richard Cochran

[permalink] [raw]
Subject: Re: [PATCH 1/2] PTP: introduce new versions of IOCTLs

On Sat, Aug 17, 2019 at 09:17:20AM -0700, Joe Perches wrote:
> Is there a case where this initialization is
> unnecessary such that it impacts performance
> given the use in ptp_ioctl?

None of these ioctls are sensitive WRT performance. They are all
setup or configuration, or in the case of the OFFSET ioctls, the tiny
extra delay before the actual measurement will not affect the result.

Thanks,
Richard

2019-08-18 22:08:25

by Joe Perches

[permalink] [raw]
Subject: Re: [PATCH 1/2] PTP: introduce new versions of IOCTLs

On Sun, 2019-08-18 at 13:11 -0700, Richard Cochran wrote:
> On Sat, Aug 17, 2019 at 09:17:20AM -0700, Joe Perches wrote:
> > Is there a case where this initialization is
> > unnecessary such that it impacts performance
> > given the use in ptp_ioctl?
>
> None of these ioctls are sensitive WRT performance. They are all
> setup or configuration, or in the case of the OFFSET ioctls, the tiny
> extra delay before the actual measurement will not affect the result.
>
> Thanks,
> Richard

Still, my preference would be to move the struct declarations
into the switch/case blocks where they are used instead of
having a large declaration block at the top of the function.

This minimizes stack use and makes the declarations use {}

Also the original patch deletes 2 case entries for
PTP_PIN_GETFUNC and PTP_PIN_SETFUNC and converts them to
PTP_PIN_GETFUNC2 and PTP_PIN_SETFUNC2 but still uses tests
for the deleted case label entries making part of the case
code block unreachable.

That's at least a defect:

- case PTP_PIN_GETFUNC:
+ case PTP_PIN_GETFUNC2:

and

- case PTP_PIN_SETFUNC:
+ case PTP_PIN_SETFUNC2:

Anyway, leaving aside that nominal defect, which
should probably leave the original case labels in place,
I suggest:

---
drivers/ptp/ptp_chardev.c | 106 +++++++++++++++++++++++++++++++++++++++-------
1 file changed, 91 insertions(+), 15 deletions(-)

diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
index 18ffe449efdf..a77f12e6326b 100644
--- a/drivers/ptp/ptp_chardev.c
+++ b/drivers/ptp/ptp_chardev.c
@@ -110,23 +110,17 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
{
struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
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 ptp_system_timestamp sts;
- struct ptp_clock_request req;
- struct ptp_clock_caps caps;
- struct ptp_clock_time *pct;
+ struct ptp_clock_info *ops = ptp->info;
unsigned int i, pin_index;
- struct ptp_pin_desc pd;
- struct timespec64 ts;
int enable, err = 0;

switch (cmd) {

case PTP_CLOCK_GETCAPS:
- memset(&caps, 0, sizeof(caps));
+ case PTP_CLOCK_GETCAPS2: {
+ struct ptp_clock_caps caps = {};
+
caps.max_adj = ptp->info->max_adj;
caps.n_alarm = ptp->info->n_alarm;
caps.n_ext_ts = ptp->info->n_ext_ts;
@@ -137,13 +131,28 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
err = -EFAULT;
break;
+ }

case PTP_EXTTS_REQUEST:
+ case PTP_EXTTS_REQUEST2: {
+ struct ptp_clock_request req = {};
+
if (copy_from_user(&req.extts, (void __user *)arg,
sizeof(req.extts))) {
err = -EFAULT;
break;
}
+ if (cmd == PTP_EXTTS_REQUEST2 &&
+ (req.extts.flags || req.extts.rsv[0] || req.extts.rsv[1])) {
+ err = -EINVAL;
+ break;
+ }
+ if (cmd == PTP_EXTTS_REQUEST) {
+ req.extts.flags = 0;
+ req.extts.rsv[0] = 0;
+ req.extts.rsv[1] = 0;
+ }
+
if (req.extts.index >= ops->n_ext_ts) {
err = -EINVAL;
break;
@@ -152,13 +161,30 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
enable = req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0;
err = ops->enable(ops, &req, enable);
break;
+ }

case PTP_PEROUT_REQUEST:
+ case PTP_PEROUT_REQUEST2: {
+ struct ptp_clock_request req = {};
+
if (copy_from_user(&req.perout, (void __user *)arg,
sizeof(req.perout))) {
err = -EFAULT;
break;
}
+ if (cmd == PTP_PEROUT_REQUEST2 &&
+ (req.perout.flags ||
+ req.perout.rsv[0] || req.perout.rsv[1] ||
+ req.perout.rsv[2] || req.perout.rsv[3])) {
+ err = -EINVAL;
+ break;
+ } else if (cmd == PTP_PEROUT_REQUEST) {
+ req.perout.flags = 0;
+ 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;
@@ -167,16 +193,26 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
enable = req.perout.period.sec || req.perout.period.nsec;
err = ops->enable(ops, &req, enable);
break;
+ }

case PTP_ENABLE_PPS:
+ case PTP_ENABLE_PPS2: {
+ struct ptp_clock_request req = {};
+
if (!capable(CAP_SYS_TIME))
return -EPERM;
req.type = PTP_CLK_REQ_PPS;
enable = arg ? 1 : 0;
err = ops->enable(ops, &req, enable);
break;
+ }

case PTP_SYS_OFFSET_PRECISE:
+ case PTP_SYS_OFFSET_PRECISE2: {
+ struct ptp_sys_offset_precise precise_offset = {};
+ struct system_device_crosststamp xtstamp;
+ struct timespec64 ts;
+
if (!ptp->info->getcrosststamp) {
err = -EOPNOTSUPP;
break;
@@ -185,7 +221,6 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
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;
@@ -199,8 +234,13 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
sizeof(precise_offset)))
err = -EFAULT;
break;
+ }

case PTP_SYS_OFFSET_EXTENDED:
+ case PTP_SYS_OFFSET_EXTENDED2: {
+ struct ptp_system_timestamp sts;
+ struct timespec64 ts;
+
if (!ptp->info->gettimex64) {
err = -EOPNOTSUPP;
break;
@@ -211,8 +251,8 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
extoff = NULL;
break;
}
- if (extoff->n_samples > PTP_MAX_SAMPLES
- || extoff->rsv[0] || extoff->rsv[1] || extoff->rsv[2]) {
+ if (extoff->n_samples > PTP_MAX_SAMPLES ||
+ extoff->rsv[0] || extoff->rsv[1] || extoff->rsv[2]) {
err = -EINVAL;
break;
}
@@ -230,8 +270,13 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
if (copy_to_user((void __user *)arg, extoff, sizeof(*extoff)))
err = -EFAULT;
break;
+ }

case PTP_SYS_OFFSET:
+ case PTP_SYS_OFFSET2: {
+ struct timespec64 ts;
+ struct ptp_clock_time *pct;
+
sysoff = memdup_user((void __user *)arg, sizeof(*sysoff));
if (IS_ERR(sysoff)) {
err = PTR_ERR(sysoff);
@@ -264,12 +309,27 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
if (copy_to_user((void __user *)arg, sysoff, sizeof(*sysoff)))
err = -EFAULT;
break;
+ }
+
+ case PTP_PIN_GETFUNC2: {
+ struct ptp_pin_desc pd;

- case PTP_PIN_GETFUNC:
if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
err = -EFAULT;
break;
}
+ if (cmd == PTP_PIN_GETFUNC2 &&
+ (pd.rsv[0] || pd.rsv[1] || pd.rsv[2] || pd.rsv[3] ||
+ pd.rsv[4])) {
+ 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;
@@ -283,12 +343,27 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
if (!err && copy_to_user((void __user *)arg, &pd, sizeof(pd)))
err = -EFAULT;
break;
+ }
+
+ case PTP_PIN_SETFUNC2: {
+ struct ptp_pin_desc pd;

- case PTP_PIN_SETFUNC:
if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
err = -EFAULT;
break;
}
+ if (cmd == PTP_PIN_SETFUNC2 &&
+ (pd.rsv[0] || pd.rsv[1] || pd.rsv[2] || pd.rsv[3] ||
+ pd.rsv[4])) {
+ 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;
@@ -300,6 +375,7 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
err = ptp_set_pinfunc(ptp, pin_index, pd.func, pd.chan);
mutex_unlock(&ptp->pincfg_mux);
break;
+ }

default:
err = -ENOTTY;


2019-08-19 15:44:38

by Richard Cochran

[permalink] [raw]
Subject: Re: [PATCH 1/2] PTP: introduce new versions of IOCTLs

On Sun, Aug 18, 2019 at 03:07:18PM -0700, Joe Perches wrote:
> Also the original patch deletes 2 case entries for
> PTP_PIN_GETFUNC and PTP_PIN_SETFUNC and converts them to
> PTP_PIN_GETFUNC2 and PTP_PIN_SETFUNC2 but still uses tests
> for the deleted case label entries making part of the case
> code block unreachable.
>
> That's at least a defect:
>
> - case PTP_PIN_GETFUNC:
> + case PTP_PIN_GETFUNC2:
>
> and
>
> - case PTP_PIN_SETFUNC:
> + case PTP_PIN_SETFUNC2:

Good catch. Felipe, please fix that!

(Regarding Joe's memset suggestion, I'll leave that to your discretion.)

Thanks,
Richard

2019-08-19 15:59:42

by Joe Perches

[permalink] [raw]
Subject: Re: [PATCH 1/2] PTP: introduce new versions of IOCTLs

On Mon, 2019-08-19 at 08:43 -0700, Richard Cochran wrote:
> On Sun, Aug 18, 2019 at 03:07:18PM -0700, Joe Perches wrote:
> > Also the original patch deletes 2 case entries for
> > PTP_PIN_GETFUNC and PTP_PIN_SETFUNC and converts them to
> > PTP_PIN_GETFUNC2 and PTP_PIN_SETFUNC2 but still uses tests
> > for the deleted case label entries making part of the case
> > code block unreachable.
> >
> > That's at least a defect:
> >
> > - case PTP_PIN_GETFUNC:
> > + case PTP_PIN_GETFUNC2:
> >
> > and
> >
> > - case PTP_PIN_SETFUNC:
> > + case PTP_PIN_SETFUNC2:
>
> Good catch. Felipe, please fix that!
>
> (Regarding Joe's memset suggestion, I'll leave that to your discretion.)

Not just how declarations are done or memset.

Minimizing unnecessary stack consumption is generally good.


2019-08-28 08:26:01

by Felipe Balbi

[permalink] [raw]
Subject: Re: [PATCH 1/2] PTP: introduce new versions of IOCTLs


Hi,

Joe Perches <[email protected]> writes:

> On Mon, 2019-08-19 at 08:43 -0700, Richard Cochran wrote:
>> On Sun, Aug 18, 2019 at 03:07:18PM -0700, Joe Perches wrote:
>> > Also the original patch deletes 2 case entries for
>> > PTP_PIN_GETFUNC and PTP_PIN_SETFUNC and converts them to
>> > PTP_PIN_GETFUNC2 and PTP_PIN_SETFUNC2 but still uses tests
>> > for the deleted case label entries making part of the case
>> > code block unreachable.
>> >
>> > That's at least a defect:
>> >
>> > - case PTP_PIN_GETFUNC:
>> > + case PTP_PIN_GETFUNC2:
>> >
>> > and
>> >
>> > - case PTP_PIN_SETFUNC:
>> > + case PTP_PIN_SETFUNC2:
>>
>> Good catch. Felipe, please fix that!
>>
>> (Regarding Joe's memset suggestion, I'll leave that to your discretion.)
>
> Not just how declarations are done or memset.
>
> Minimizing unnecessary stack consumption is generally good.

Originally I had memset only on the three cases where they were
needed. Richard, which do you prefer? I don't mind changing it back.

--
balbi


Attachments:
signature.asc (847.00 B)

2019-08-28 12:59:03

by Richard Cochran

[permalink] [raw]
Subject: Re: [PATCH 1/2] PTP: introduce new versions of IOCTLs

On Wed, Aug 28, 2019 at 11:23:33AM +0300, Felipe Balbi wrote:
> Originally I had memset only on the three cases where they were
> needed. Richard, which do you prefer? I don't mind changing it back.

Go ahead and change it back.

Thanks,
Richard