Attempt to mitigate poor initialization of arc4 by one-shot
reinitialization from yarrow right after good entropy is harvested.

Approved by:    secteam (delphij)
MFC after:      1 week
Fix the symlink creation from r249484 so that repeated
installs work correctly.

Suggested by Tijl Coosemans.
An even more refined version of r249484, until we can come up with
a good fix for the -print-file-name=include breakage.

As suggested by Andrey Chernov.
Fix the uart(4) module build.  Without uart_dev_lpc the module cannot be loaded.
Use uint32_t for fields that are fetched via ath_hal_getcapability().
Print out the chainmask configuration.
.. don't know how this snuck into this commit. Sorry.

Fix compile build before anyone notices.
Add a debug statement to log the currently chosen chainmask configuration.
sem: Restart the POSIX sem_* calls after signals with SA_RESTART set.

Programs often do not expect an [EINTR] return from sem_wait() and POSIX
only allows it if the signal was installed without SA_RESTART. The timeout
in sem_timedwait() is absolute so it can be restarted normally.

The umtx call can be invoked with a relative timeout and in that case
[ERESTART] must be changed to [EINTR]. However, libc does not do this.

The old POSIX semaphore implementation did this correctly (before r249566),
unlike the new umtx one.

It may be desirable to avoid [EINTR] completely, which matches the pthread
functions and is explicitly permitted by POSIX. However, the kernel must
return [EINTR] at least for signals with SA_RESTART clear, otherwise pthread
cancellation will not abort a semaphore wait. In this commit, only restore
the 8.x behaviour which is also permitted by POSIX.

Discussed with:	jhb
MFC after:	1 week
Don't compare unsigned socklen_t against < 0.

Reviewed by:	jhb
Include PID in the error message which is printed when the maxproc limit
is exceeded. Improve formatting of the message while here.

PR:		kern/60550
Submitted by:	Lowell Gilbert, bde
Implement a very basic multi-PHY aware switch device.

This is intended to be used as a stop-gap for switch devices
which expose multiple ethernet PHYs but we don't have a driver
for - here, etherswitchcfg and the general switch configuration
API can be used to interface to said PHYs.

Submitted by:	Luiz Otavio O Souza <loos.br@gmail.com>
Fix -Wmissing-variable-declarations compiler warnings.

References:
https://www.illumos.org/issues/3700
Add the Clang specific -Wmissing-variable-declarations to WARNS=6.

This compiler flag enforces that that people either mark variables
static or use an external declarations for the variable, similar to how
-Wmissing-prototypes works for functions.

Due to the fact that Yacc/Lex generate code that cannot trivially be
changed to not warn because of this (lots of yy* variables), add a
NO_WMISSING_VARIABLE_DECLARATIONS that can be used to turn off this
specific compiler warning.

Announced on:	toolchain@
Update chio(1) and ch(4) to support reporting element designators.

This allows mapping a tape drive in a changer (as reported by
'chio status') to a sa(4) driver instance by comparing the
serial numbers.

The designators can be ASCII (which is printed out directly), binary
(which is printed in hex format) or UTF-8, which is printed in either
native UTF-8 format if the terminal can support it, or in %XX notation
for non-ASCII characters.  Thanks to Hiroki Sato <hrs@> for the
explaining UTF-8 printing and example UTF-8 printing code.

chio.h:		Modify the changer_element_status structure to add new
		fields and definitions from the SMC3r16 spec.

		Rename the original CHIOGSTATUS ioctl to OCHIOGTATUS and
		define a new CHIOGSTATUS ioctl.

		Clean up some tab/space issues.

chio.c: 	For the 'status' subcommand, print the designator field
		if it is supplied by a device.

scsi_ch.h:	Add new flags for DVCID and CURDATA to the READ
		ELEMENT STATUS command structure.

		Add a read_element_status_device_id structure
		for the data fields in the new standard. Add new
		unions, dt_or_obsolete and voltage_devid, to hold
		and address data from either SCSI-2 or newer devices.

scsi_ch.c:	Implement support for fetching device IDs with READ
		ELEMENT STATUS data.

		Add new arguments to scsi_read_element_status() to
		allow the user to request the DVCID and CURDATA bits.
		This isn't compiled into libcam (it's only an internal
		kernel interface), so we don't need any special
		handling for the API change.

		If the user issues the new CHIOGSTATUS ioctl, copy all of
		the available element status data out.  If he issues the
		OCHIOGSTATUS ioctl, we don't copy the new fields in the
		structure.

		Fix a bug in chopen() that would result in the peripheral
		never getting unheld if chgetparams() failed.

Sponsored by:	Spectra Logic
Submitted by:	Po-Li Soong
MFC After:	1 week
Merge remote-tracking branch 'upstream/master'