MFC r313249:
Style, use tab after #define.

MFC r302063:
Avoid the active object marking for vm.vmtotal sysctl.

MFC r283924

Provide vnode in memory map info for files on tmpfs

When providing memory map information to userland, populate the vnode pointer
for tmpfs files. Set the memory mapping to appear as a vnode type, to match
FreeBSD 9 behavior.

This fixes the use of tmpfs files with the dtrace pid provider,
procstat -v, procfs, linprocfs, pmc (pmcstat), and ptrace (PT_VM_ENTRY).

Submitted by: Eric Badger <eric@badgerio.us> (initial revision)
Obtained from: Dell Inc.
PR: 198431

MFC r285878:
Revert r173708's modifications to vm_object_page_remove().
This fixes inconsistencies encountered by vm_object_unwire() or
by the buffer cache when the file is truncated.

MFC r277828:
Update mtime for tmpfs files modified through memory mapping.

MFC r277969:
Update both ctime and mtime for writes to tmpfs files.

MFC r277972:
Remove single-use boolean.

MFC r278151:
Remove duplicated assignment.

Fix a leak of the wired pages when unwiring of the PROT_NONE-mapped
wired region. Rework the handling of unwire to do the it in batch,
both at pmap and object level.

All commits below are by alc.

MFC r268327:
Introduce pmap_unwire().

MFC r268591:
Implement pmap_unwire() for powerpc.

MFC r268776:
Implement pmap_unwire() for arm.

MFC r268806:
pmap_unwire(9) man page.

MFC r269134:
When unwiring a region of an address space, do not assume that the
underlying physical pages are mapped by the pmap. This fixes a leak
of the wired pages on the unwiring of the region mapped with no access
allowed.

MFC r269339:
In the implementation of the new function pmap_unwire(), the call to
MOEA64_PVO_TO_PTE() must be performed before any changes are made to the
PVO. Otherwise, MOEA64_PVO_TO_PTE() will panic.

MFC r269365:
Correct a long-standing problem in moea{,64}_pvo_enter() that was revealed
by the combination of r268591 and r269134: When we attempt to add the
wired attribute to an existing mapping, moea{,64}_pvo_enter() do nothing.
(They only set the wired attribute on newly created mappings.)

MFC r269433:
Handle wiring failures in vm_map_wire() with the new functions
pmap_unwire() and vm_object_unwire().
Retire vm_fault_{un,}wire(), since they are no longer used.

MFC r269438:
Rewrite a loop in vm_map_wire() so that gcc doesn't think that the variable
"rv" is uninitialized.

MFC r269485:
Retire pmap_change_wiring().

Reviewed by: alc

MFC r269642:
Add wrappers to assert that vm object is unlocked and for try upgrade.

MFC r268615:
Add OBJ_TMPFS_NODE flag.

MFC r268616:
Set the OBJ_TMPFS_NODE flag for vm_object of VREG tmpfs node.

MFC r269053:
Correct assertion. tmpfs vm object is always at the bottom of
the shadow chain.

MFC r283924

Provide vnode in memory map info for files on tmpfs

When providing memory map information to userland, populate the vnode pointer
for tmpfs files. Set the memory mapping to appear as a vnode type, to match
FreeBSD 9 behavior.

This fixes the use of tmpfs files with the dtrace pid provider,
procstat -v, procfs, linprocfs, pmc (pmcstat), and ptrace (PT_VM_ENTRY).

Submitted by: Eric Badger <eric@badgerio.us> (initial revision)
Obtained from: Dell Inc.
PR: 198431

MFC r285878:
Revert r173708's modifications to vm_object_page_remove().
This fixes inconsistencies encountered by vm_object_unwire() or
by the buffer cache when the file is truncated.

MFC r277828:
Update mtime for tmpfs files modified through memory mapping.

MFC r277969:
Update both ctime and mtime for writes to tmpfs files.

MFC r277972:
Remove single-use boolean.

MFC r278151:
Remove duplicated assignment.

Fix a leak of the wired pages when unwiring of the PROT_NONE-mapped
wired region. Rework the handling of unwire to do the it in batch,
both at pmap and object level.

All commits below are by alc.

MFC r268327:
Introduce pmap_unwire().

MFC r268591:
Implement pmap_unwire() for powerpc.

MFC r268776:
Implement pmap_unwire() for arm.

MFC r268806:
pmap_unwire(9) man page.

MFC r269134:
When unwiring a region of an address space, do not assume that the
underlying physical pages are mapped by the pmap. This fixes a leak
of the wired pages on the unwiring of the region mapped with no access
allowed.

MFC r269339:
In the implementation of the new function pmap_unwire(), the call to
MOEA64_PVO_TO_PTE() must be performed before any changes are made to the
PVO. Otherwise, MOEA64_PVO_TO_PTE() will panic.

MFC r269365:
Correct a long-standing problem in moea{,64}_pvo_enter() that was revealed
by the combination of r268591 and r269134: When we attempt to add the
wired attribute to an existing mapping, moea{,64}_pvo_enter() do nothing.
(They only set the wired attribute on newly created mappings.)

MFC r269433:
Handle wiring failures in vm_map_wire() with the new functions
pmap_unwire() and vm_object_unwire().
Retire vm_fault_{un,}wire(), since they are no longer used.

MFC r269438:
Rewrite a loop in vm_map_wire() so that gcc doesn't think that the variable
"rv" is uninitialized.

MFC r269485:
Retire pmap_change_wiring().

Reviewed by: alc

MFC r269642:
Add wrappers to assert that vm object is unlocked and for try upgrade.

MFC r268615:
Add OBJ_TMPFS_NODE flag.

MFC r268616:
Set the OBJ_TMPFS_NODE flag for vm_object of VREG tmpfs node.

MFC r269053:
Correct assertion. tmpfs vm object is always at the bottom of
the shadow chain.