lib: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

libkvm: fix kvm_walk_pages

Correct bitmap operations in _kvm_bitmap_next.

Reviewed by: jhb
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19183

Always use 64-bit physical addresses for dump_avail[] in minidumps

As of r365978, minidumps include a copy of dump_avail[]. This is an
array of vm_paddr_t ranges. libkvm walks the array assuming that
sizeof(vm_paddr_t) is equal to the platform "word size", but that's not
correct on some platforms. For instance, i386 uses a 64-bit vm_paddr_t.

Fix the problem by always dumping 64-bit addresses. On platforms where
vm_paddr_t is 32 bits wide, namely arm and mips (sometimes), translate
dump_avail[] to an array of uint64_t ranges. With this change, libkvm
no longer needs to maintain a notion of the target word size, so get rid
of it.

This is a no-op on platforms where sizeof(vm_paddr_t) == 8.

Reviewed by: alc, kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D27082

Sparsify the vm_page_dump bitmap

On Ampere Altra systems, the sparse population of RAM within the
physical address space causes the vm_page_dump bitmap to be much
larger than necessary, increasing the size from ~8 Mib to > 2 Gib
(and overflowing `int` for the size).

Changing the page dump bitmap also changes the minidump file
format, so changes are also necessary in libkvm.

Reviewed by: jhb
Approved by: scottl (implicit)
MFC after: 1 week
Sponsored by: Ampere Computing, Inc.
Differential Revision: https://reviews.freebsd.org/D26131

Partially revert VNET change and expand VNET structure.

Revert parts of r353274 replacing vnet_state with a shutdown flag.

Not having the state flag for the current SI_SUB_* makes it harder to debug
kernel or module panics related to VNET bringup or teardown.
Not having the state also does not allow us to check for other dependency
levels between components, e.g. for moving interfaces.

Expand the VNET structure with the new boolean flag indicating that we are
doing a shutdown of a given vnet and update the vnet magic cookie for the
change.

Update libkvm to compile with a bool in the kernel struct.

Bump __FreeBSD_version for (external) module builds to more easily detect
the change.

Reviewed by: hselasky
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D23097

kvm: fix types for cross-debugging

As with other libkvm interfaces use maximum-sized types to support
cross-debugging (e.g. a 64-bit vmcore on a 32-bit host). See
https://lists.freebsd.org/pipermail/svn-src-all/2019-February/176051.html
for further discussion.

This is an API-breaking change, but there are few consumers of this
interface today.

Reviewed by: will
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21945

Add powerpc support to libkvm probe function

PowerPC kernels are of DYN type, instead of EXEC.

Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D21583

libkvm: fix build failures

libkvm: fix 'index' shadowing.

libkvm: add kvm_walk_pages API.

This API allows callers to enumerate all known pages, including any
direct map & kernel map virtual addresses, physical addresses, size,
offset into the core, & protection configured.

For architectures that support direct map addresses, also generate pages
for any direct map only addresses that are not associated with kernel
map addresses.

Fix page size portability issue left behind from previous kvm page table
lookup interface.

Reviewed by: jhb
Sponsored by: Backtrace I/O
Differential Revision: https://reviews.freebsd.org/D12279

Renumber copyright clause 4

Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96

Fix memory leak.

CID: 1367751
Reviewed by: jhb

libkvm: Improve physical address lookup scaling.

Instead of using a hash table to convert physical page addresses to offsets
in the sparse page array, cache the number of bits set for each 4MB chunk of
physical pages. Upon lookup, find the nearest cached population count, then
add/subtract the number of bits from that point to the page's PTE bit.
Then multiply by page size and add to the sparse page map's base offset.

This replaces O(n) worst-case lookup with O(1) (plus a small number of bits
to scan in the bitmap). Also, for a 128GB system, a typical kernel core of
about 8GB will now only require ~4.5MB of RAM for this approach instead of
~48MB as with the hash table.

More concretely, /usr/sbin/crashinfo against the same core improves from a
max RSS of 188MB and wall time of 43.72s (33.25 user 2.94 sys) to 135MB and
9.43s (2.58 user 1.47 sys). Running "thread apply all bt" in kgdb has a
similar RSS improvement, and wall time drops from 4.44s to 1.93s.

Reviewed by: jhb
Sponsored by: Backtrace I/O

libkvm: Put private kvm routines in kvm_private.c.