MFC r337871, r339970, r342151, r342161, r343123-r343124, r344226, r344234,
r344248, r344387

r337871:
pkgfs_init: Initialize pkg

new_package may not set *pp if it errors out, leaving pkg uninitialized.

r339970:
Remove unnecessary include from libstand.

r342151:
loader: zfs reader should not probe partitionless disks

First of all, normal setups can not boot such pools as the tools
do not support installing boot programs.

Secondly, for proper pool configuration detection, we need to checks all
four label copies on disk, 2 from front and 2 from the end of the disk,
but zfs label does not contain the size of the disk - so we depend on
firmware to report the correct disk size or use information from the
partition table.

Without partition table, we only can rely on firmware to report and support
disk IO properly.

There is a specific case: 8TB disks are reported by BIOS to have 4294967295
sectors (0x00000000ffffffff), the sectors reported by OS is 15628053168
(0x00000003a3812ab0), so the reported size is less than actual but is hitting
32-bit max. Unfortuantely the real limit must be even lower because probing
this disk in this system will wnd up with hung system.

UEFI boot of this system seems not to be affected.

r342161:
loader: zfs reader should not probe partitionless disks (UEFI case)

With r342151 I did fix the BIOS version of zfs_probe_dev() from accessing
the whole disk, but the fix was not complete - we actually did not check
if the device name was really for whole disk. Since UEFI version
is only calling the zfs_probe_dev() with partitions and not with whole
disk, the UEFI loader was not able to find the zfs pools.

This update does correct the issue by calling archsw.arch_getdev() to
translate the device name back to dev_desc, and we have whole disk when both
partition and slice values are -1.

r343123:
loader should ignore active multi_vdev_crash_dump feature on zpool

Since the loader zfs reader does not need to read the dump zvol, we can
just enable the feature.

illumos issue #9051 https://www.illumos.org/issues/9051

r343124:
libsa: add asprintf()

asprintf() is a nice tool for string processing.

r344226:
Fix memory corruption bug introduced in r325310

The bug occurred when a bounce buffer was used and the requested read
size was greater than the size of the bounce buffer. This commit also
rewrites the read logic so that it is easier to systematically verify
all alignment and size cases.

r344234:
It turns out r344226 narrowed the overrun bug but did not eliminate it entirely

This commit fixes a remaining output buffer overrun in the
single-sector case when there is a non-zero tail.

r344248:
cd9660: dirmatch fails to unmatch when name is prefix for directory record

Loader does fail to properly match the file name in directory record and
does open file based on prefix match.

For fix, we check the name lengths first.

r344387:
loader: really fix cd9660 dirmatch

The cd9660_open() does pass whole path to dirmatch() and we need to
compare only the current path component, not full path.

Additinally, skip over duplicate / (if any) and check if the last component
in the path was meant to be directory (having trailing /). If it is in fact
a file, error out.

MFC r325834,r325997,326502: Move sys/boot to stand/

This is effectively a direct commit to stable/11, due to differences between
stable/11 and head. Changes to DTS in sys/boot/fdt/dts were often
accompanied by kernel changes. Many of these were also risc-v updates that
likely had many more dependencies to MFC.

Because of this, sys/boot/fdt/dts remains as-is while everything else in
sys/boot relocates to stand/.

r325834: Move sys/boot to stand. Fix all references to new location

r325997: Remove empty directories.

r326502: Document the sys/boot -> stand move in hier.7 and the top-level README.

MFC r324551: Move lib/libstand to sys/boot/libsa

MFC Loader Fixes 2017q2: r316437,r316577,r316578,r316585,r316590,r316612,
r316625,r316628,r316654,r316682,r316704,r316771,r317092,r317097,r317099,
r317652,r317785,r317886,r317887,r318142,r318320,r318356,r318678,r318754,
r318982,r318986,r318987,r318988,r318989,r318990,r318991,r318992,r318993,
r318994,r318999,r319083,r319084,r319085,r320011,r320234,r320288,r320304,
r320467,r320482

r316437: Small cleanup to make i386/loader match efi/loader boot environment
code

r316577: loader: part.c cstyle cleanup

r316578: loader: want mechanism to avoid RA with bcache

r316585: loader: zfs reader should check all labels

r316590: libstand/dosfs: cache FAT32 in 128 Kb blocks to save loader memory

r316612: In r298230 the value of HEAP_MIN was changed from 3MB to 64MB.
Correct a comment.

r316625: Do not use -msoft-float with intention of disabling FP on aarch64

r316628: Silence GCC warning by initializing the local variable.

r316654: loader: r316585 did miss userboot update

r316682: loader: r316585 did miss sparc/ofw

r316704: loader.efi: only fetch zfs pool guid for the actual boot device

r316771: loader: Avoid possible overflow via environment variable

r317092: loader: zfs reader vdev_probe should check for minimum device size

r317097: loader: F_READ/F_WRITE should be checked against masked flag

r317099: loader: uboot disk ioctl should call disk_ioctl

r317652: loader.efi: ResetSystem does not use data with EFI_SUCCESS

r317785: zfsboot: drvsize() may be unusable on some systems

r317886: distinguish NFS versus TFTP boot by rootpath

r317887: loader: network read rework

r318142: libstand: NULL pointer dereference in rarp

r318320: loader: add ip layer code into libstand

r318356: libstand: increase nfs max read size to 16k

r318678: Replacing iterating over rootpath by strsep(3).

r318754: Pass -N directly to ld via -Wl rather than passing it to the
compiler driver.

r318982: Pass a "FREEBSD" user-class in PXE dhcp request

r318986: add a comment on vendor index 19 and 20 to avoid confusion

r318987: Support URI scheme for root-path in netbooting

r318988: Always build tftpfs support along with nfs for pxeboot

r318989: Always issue the pxe request

r318990: Partially revert r314948

r318991: Document recent changes on pxeboot

r318992: Capitalize DHCP

r318993: Use the usual FreeBSD spelling for the DHCP user class

r318994: Catch with the change in the user class

r318999: Update the comments concerning net_parse_rootpath to reflect what
it is now

r319083: Followup on the user-class changes

r319084: Small cleanup in dev_net.c

r319085: use the same option list for dhcp discovery and request

r320011: Add chain loader support for loader

r320234: Make structure padding explicit in EFI_MEMORY_DESCRIPTOR

r320288: Allow Clang's integrated assembler to assemble boot0

r320304: loader.efi: Disable smbios for arm

r320467: loader: chain load relocate data declaration is bad

r320482: As with arm64 mark the EFI PE header as allocated on arm.

PR: 218473

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Add #include <netinet/in_pcb.h> for missing forward declation of
struct inpcb.

IP_TTL is an IP socket option, not a TTL value. Use IPDEFTTL
instead.

Remove California Regent's clause 3, per letter

Use %z to print size_t values.

Remove 'register' keyword.

Add __FBSDID()s to libstand

Correct the returned UDP datagram length. See the PR for a more comprehensive
description of the fix.

PR: misc/25503
Submitted by: Jim Browne <jbrowne@jbrowne.com>
MFC after: 1 week

Break out sendudp and readudp from net.c. This is for PXE, so it
can use its own UDP interface.