spelling

Use a per-UVM object lock to serialize the lower part of the fault handler.

Like the per-amap lock the `vmobjlock' is principally used to serialized
access to objects in the fault handler to allow faults occurring on
different CPUs and different objects to be processed in parallel.

The fault handler now acquires the `vmobjlock' of a given UVM object as
soon as it finds one. For now a write-lock is always acquired even if
some operations could use a read-lock.

Every pager, corresponding to a different kind of UVM object, now expect
the UVM object to be locked and some operations, like *_get() return it
unlocked. This is enforced by assertions checking for rw_write_held().

The KERNEL_LOCK() is now pushed to the VFS boundary in the vnode pager.

To ensure the correct amap or object lock is held when modifying a page
many uvm_page* operations are now asserting for the "owner" lock.
However, fields of the "struct vm_page" are still being protected by the
global `pageqlock'. To prevent lock ordering issues with the new
`vmobjlock' and to reduce differences with NetBSD this lock is now taken
and released for each page instead of around the whole loop.

This commit does not remove the KERNEL_LOCK/UNLOCK() dance. Unlocking
will follow if there is no fallout.

Ported from NetBSD, tested by many, thanks!

ok kettenis@, kn@

Introduce a dummy uvm_obj_destroy() interface. This function will be
used in the near future (by mpi@) to improve the locking for uvm objects.
Introducing this function now will me allow me to call it in the
appropriate place in the drm code.

ok mpi@, jsg@

Introduce dummy pagers for 'special' subsystems using UVM objects.

Some pmaps (x86, hppa) and the buffer cache rely on UVM objects to allocate
and manipulate pages. These objects should not be manipulated by uvm_fault()
and do not currently require the same locking enforcement.

Use the dummy pagers to explicitly document which UVM functions are meant to
manipulate UVM objects (uobj) that do not need the upcoming `vmobjlock' and
instead still rely on the KERNEL_LOCK().

Tested by many as part of a larger diff.

ok kettenis@, beck@

Change the prefix of UVM object functions to match NetBSD's.

For example uvm_objinit() becomes uvm_obj_init(). Reduce differences
between the trees and help porting new functions needed for UVM object
locking.

No functionnal change.

Use a macro to assert that given uobjs correspond to anonymous objects.

Reduce the difference with NetBSD.

ok kettenis@

Constify and use C99 initializer for "struct uvm_pagerops".

While here put some KERNEL_ASSERT_LOCKED() in the functions called from
the page fault handler. The removal of locking of `uobj' will need to be
revisited and these are good indicator that something is missing and that
many comments are lying.

ok kettenis

Add uvm_objfree function to free all pages in a uvm_obj in one go.
Use this in the buffer cache to free all the pages from a buffer,
resulting in a considerable speedup when throwing away pages from
the buffer cache.

Lots of work done with mlarkin and kettenis

ok kettinis@ deraadt@

move the vm_page struct from being stored in RB macro trees to RBT functions

vm_page structs go into three trees, uvm_objtree, uvm_pmr_addr, and
uvm_pmr_size. all these have been moved to RBT code.

this should give us a decent chunk of code space back.

Chuck Cranor rescinded clauses in his license
on the 2nd of February 2011 in NetBSD.

http://marc.info/?l=netbsd-source-changes&m=129658899212732&w=2
http://marc.info/?l=netbsd-source-changes&m=129659095515558&w=2
http://marc.info/?l=netbsd-source-changes&m=129659157916514&w=2
http://marc.info/?l=netbsd-source-changes&m=129665962324372&w=2
http://marc.info/?l=netbsd-source-changes&m=129666033625342&w=2
http://marc.info/?l=netbsd-source-changes&m=129666052825545&w=2
http://marc.info/?l=netbsd-source-changes&m=129666922906480&w=2
http://marc.info/?l=netbsd-source-changes&m=129667725518082&w=2

Fix some potential integer overflows caused by converting a page number into
an offset/size/address by shifting by PAGE_SHIFT. Make uvm_objwrire/unwire
use voff_t instead of off_t. The former is the right type here even if it is
equivalent to the latter.

Inspired by a somewhat similar changes in Bitrig.

ok deraadt@, guenther@

remove simple_locks from uvm code. ok beck deraadt

fix typos; while here, improve spacing in comments.

changes to libevent and zlib headers sent to the upstream maintainers.

ok jmc@ (for typos), millert@

Right now, if anything internal changes with a uvm object, diverse
places in the tree need to be touched to update the object
initialisation with respect to that.

So, make a function (uvm_initobj) that takes the refcount, object and
pager ops and does this initialisation for us. This should save on
maintainance in the future.

looked good to fgs@. Tedu complained about the British spelling but OKed
it anyway.

re-add uvm_objwire and uvm_objunwire. needed for intel GEM support.

It was backed out as part of the date-based revert after c2k9.

"you can commit that" kettenis@

original diff oked by ariane@, art@.

reintroduce the uvm_tree commit.

Now instead of the global object hashtable, we have a per object tree.

Testing shows no performance difference and a slight code shrink. OTOH when
locking is more fine grained this should be faster due to lock contention on
uvm.hashlock.

ok thib@, art@.

date based reversion of uvm to the 4th May.

More backouts in line with previous ones, this appears to bring us back to a
stable condition.

A machine forced to 64mb of ram cycled 10GB through swap with this diff
and is still running as I type this. Other tests by ariane@ and thib@
also seem to show that it's alright.

ok deraadt@, thib@, ariane@

Backout all changes to uvm after pmemrange (which will be backed out
separately).

a change at or just before the hackathon has either exposed or added a
very very nasty memory corruption bug that is giving us hell right now.
So in the interest of kernel stability these diffs are being backed out
until such a time as that corruption bug has been found and squashed,
then the ones that are proven good may slowly return.

a quick hitlist of the main commits this backs out:

mine:
uvm_objwire
the lock change in uvm_swap.c
using trees for uvm objects instead of the hash
removing the pgo_releasepg callback.

art@'s:
putting pmap_page_protect(VM_PROT_NONE) in uvm_pagedeactivate() since
all callers called that just prior anyway.

ok beck@, ariane@.

prompted by deraadt@.

Add uvm_objwire() and uvm_objunwire(), I need this for some of my crazy
shitz.

Code mostly from netbsd with some tweaks from me. The loaning case is
specifcically if 0ed out right now because we do not do loaning.

ok ariane@, art@.

Instead of the global hash table with the terrible hashfunction and a
global lock, switch the uvm object pages to being kept in a per-object
RB_TREE. Right now this is approximately the same speed, but cleaner.
When biglock usage is reduced this will improve concurrency due to lock
contention..

ok beck@ art@. Thanks to jasper for the speed testing.

Instead of managing pages for intrsafe maps in special objects (aka.
kmem_object) just so that we can remove them, just use pmap_extract
to get the pages to free and simplify a lot of code to not deal with
the list of intrsafe maps, intrsafe objects, etc.

miod@ ok

- Make a UVM_OBJ_IS_DEVICE macro.
- Use it to skip device mappings while dumping core.
- Ignore EFAULT errors while dumping core since they can happen
even for valid mappings. Just skip that part of the core file and
let it get automagically zero-filled.

This fixes the broken X core dumps that people have been seeing and also
fixes some other potential problems that could prevent core dumps (mmaps
beyond EOF, etc.).

tedu@ ok

UBC was a disaster. It worked very good when it worked, but on some
machines or some configurations or in some phase of the moon (we actually
don't know when or why) files disappeared. Since we've not been able to
track down the problem in two weeks intense debugging and we need -current
to be stable, back out everything to a state it had before UBC.

We apologise for the inconvenience.

branches: 1.7.2;
Sync in more uvm from NetBSD. Mostly just cosmetic stuff.
Contains also support for page coloring.

Bring in more changes from NetBSD. Mostly pagedaemon improvements.

$OpenBSD$

Bring in some new UVM code from NetBSD (not current).

- Introduce a new type of map that are interrupt safe and never allow faults
in them. mb_map and kmem_map are made intrsafe.
- Add "access protection" to uvm_vslock (to be passed down to uvm_fault and
later to pmap_enter).
- madvise(2) now works.
- various cleanups.

branches: 1.3.4;
sync with NetBSD from 1999.05.24 (there is a reason for this date)
Mostly cleanups, but also a few improvements to pagedaemon for better
handling of low memory and/or low swap conditions.

add OpenBSD tags

Import of uvm from NetBSD. Some local changes, some code disabled

Use a per-UVM object lock to serialize the lower part of the fault handler.

Like the per-amap lock the `vmobjlock' is principally used to serialized
access to objects in the fault handler to allow faults occurring on
different CPUs and different objects to be processed in parallel.

The fault handler now acquires the `vmobjlock' of a given UVM object as
soon as it finds one. For now a write-lock is always acquired even if
some operations could use a read-lock.

Every pager, corresponding to a different kind of UVM object, now expect
the UVM object to be locked and some operations, like *_get() return it
unlocked. This is enforced by assertions checking for rw_write_held().

The KERNEL_LOCK() is now pushed to the VFS boundary in the vnode pager.

To ensure the correct amap or object lock is held when modifying a page
many uvm_page* operations are now asserting for the "owner" lock.
However, fields of the "struct vm_page" are still being protected by the
global `pageqlock'. To prevent lock ordering issues with the new
`vmobjlock' and to reduce differences with NetBSD this lock is now taken
and released for each page instead of around the whole loop.

This commit does not remove the KERNEL_LOCK/UNLOCK() dance. Unlocking
will follow if there is no fallout.

Ported from NetBSD, tested by many, thanks!

ok kettenis@, kn@

Introduce a dummy uvm_obj_destroy() interface. This function will be
used in the near future (by mpi@) to improve the locking for uvm objects.
Introducing this function now will me allow me to call it in the
appropriate place in the drm code.

ok mpi@, jsg@

Introduce dummy pagers for 'special' subsystems using UVM objects.

Some pmaps (x86, hppa) and the buffer cache rely on UVM objects to allocate
and manipulate pages. These objects should not be manipulated by uvm_fault()
and do not currently require the same locking enforcement.

Use the dummy pagers to explicitly document which UVM functions are meant to
manipulate UVM objects (uobj) that do not need the upcoming `vmobjlock' and
instead still rely on the KERNEL_LOCK().

Tested by many as part of a larger diff.

ok kettenis@, beck@

Change the prefix of UVM object functions to match NetBSD's.

For example uvm_objinit() becomes uvm_obj_init(). Reduce differences
between the trees and help porting new functions needed for UVM object
locking.

No functionnal change.

Use a macro to assert that given uobjs correspond to anonymous objects.

Reduce the difference with NetBSD.

ok kettenis@

Constify and use C99 initializer for "struct uvm_pagerops".

While here put some KERNEL_ASSERT_LOCKED() in the functions called from
the page fault handler. The removal of locking of `uobj' will need to be
revisited and these are good indicator that something is missing and that
many comments are lying.

ok kettenis

Add uvm_objfree function to free all pages in a uvm_obj in one go.
Use this in the buffer cache to free all the pages from a buffer,
resulting in a considerable speedup when throwing away pages from
the buffer cache.

Lots of work done with mlarkin and kettenis

ok kettinis@ deraadt@

move the vm_page struct from being stored in RB macro trees to RBT functions

vm_page structs go into three trees, uvm_objtree, uvm_pmr_addr, and
uvm_pmr_size. all these have been moved to RBT code.

this should give us a decent chunk of code space back.

Chuck Cranor rescinded clauses in his license
on the 2nd of February 2011 in NetBSD.

http://marc.info/?l=netbsd-source-changes&m=129658899212732&w=2
http://marc.info/?l=netbsd-source-changes&m=129659095515558&w=2
http://marc.info/?l=netbsd-source-changes&m=129659157916514&w=2
http://marc.info/?l=netbsd-source-changes&m=129665962324372&w=2
http://marc.info/?l=netbsd-source-changes&m=129666033625342&w=2
http://marc.info/?l=netbsd-source-changes&m=129666052825545&w=2
http://marc.info/?l=netbsd-source-changes&m=129666922906480&w=2
http://marc.info/?l=netbsd-source-changes&m=129667725518082&w=2

Fix some potential integer overflows caused by converting a page number into
an offset/size/address by shifting by PAGE_SHIFT. Make uvm_objwrire/unwire
use voff_t instead of off_t. The former is the right type here even if it is
equivalent to the latter.

Inspired by a somewhat similar changes in Bitrig.

ok deraadt@, guenther@

remove simple_locks from uvm code. ok beck deraadt

fix typos; while here, improve spacing in comments.

changes to libevent and zlib headers sent to the upstream maintainers.

ok jmc@ (for typos), millert@

Right now, if anything internal changes with a uvm object, diverse
places in the tree need to be touched to update the object
initialisation with respect to that.

So, make a function (uvm_initobj) that takes the refcount, object and
pager ops and does this initialisation for us. This should save on
maintainance in the future.

looked good to fgs@. Tedu complained about the British spelling but OKed
it anyway.

re-add uvm_objwire and uvm_objunwire. needed for intel GEM support.

It was backed out as part of the date-based revert after c2k9.

"you can commit that" kettenis@

original diff oked by ariane@, art@.

reintroduce the uvm_tree commit.

Now instead of the global object hashtable, we have a per object tree.

Testing shows no performance difference and a slight code shrink. OTOH when
locking is more fine grained this should be faster due to lock contention on
uvm.hashlock.

ok thib@, art@.

date based reversion of uvm to the 4th May.

More backouts in line with previous ones, this appears to bring us back to a
stable condition.

A machine forced to 64mb of ram cycled 10GB through swap with this diff
and is still running as I type this. Other tests by ariane@ and thib@
also seem to show that it's alright.

ok deraadt@, thib@, ariane@

Backout all changes to uvm after pmemrange (which will be backed out
separately).

a change at or just before the hackathon has either exposed or added a
very very nasty memory corruption bug that is giving us hell right now.
So in the interest of kernel stability these diffs are being backed out
until such a time as that corruption bug has been found and squashed,
then the ones that are proven good may slowly return.

a quick hitlist of the main commits this backs out:

mine:
uvm_objwire
the lock change in uvm_swap.c
using trees for uvm objects instead of the hash
removing the pgo_releasepg callback.

art@'s:
putting pmap_page_protect(VM_PROT_NONE) in uvm_pagedeactivate() since
all callers called that just prior anyway.

ok beck@, ariane@.

prompted by deraadt@.

Add uvm_objwire() and uvm_objunwire(), I need this for some of my crazy
shitz.

Code mostly from netbsd with some tweaks from me. The loaning case is
specifcically if 0ed out right now because we do not do loaning.

ok ariane@, art@.

Instead of the global hash table with the terrible hashfunction and a
global lock, switch the uvm object pages to being kept in a per-object
RB_TREE. Right now this is approximately the same speed, but cleaner.
When biglock usage is reduced this will improve concurrency due to lock
contention..

ok beck@ art@. Thanks to jasper for the speed testing.

Instead of managing pages for intrsafe maps in special objects (aka.
kmem_object) just so that we can remove them, just use pmap_extract
to get the pages to free and simplify a lot of code to not deal with
the list of intrsafe maps, intrsafe objects, etc.

miod@ ok

- Make a UVM_OBJ_IS_DEVICE macro.
- Use it to skip device mappings while dumping core.
- Ignore EFAULT errors while dumping core since they can happen
even for valid mappings. Just skip that part of the core file and
let it get automagically zero-filled.

This fixes the broken X core dumps that people have been seeing and also
fixes some other potential problems that could prevent core dumps (mmaps
beyond EOF, etc.).

tedu@ ok

UBC was a disaster. It worked very good when it worked, but on some
machines or some configurations or in some phase of the moon (we actually
don't know when or why) files disappeared. Since we've not been able to
track down the problem in two weeks intense debugging and we need -current
to be stable, back out everything to a state it had before UBC.

We apologise for the inconvenience.

branches: 1.7.2;
Sync in more uvm from NetBSD. Mostly just cosmetic stuff.
Contains also support for page coloring.

Bring in more changes from NetBSD. Mostly pagedaemon improvements.

$OpenBSD$

Bring in some new UVM code from NetBSD (not current).

- Introduce a new type of map that are interrupt safe and never allow faults
in them. mb_map and kmem_map are made intrsafe.
- Add "access protection" to uvm_vslock (to be passed down to uvm_fault and
later to pmap_enter).
- madvise(2) now works.
- various cleanups.

branches: 1.3.4;
sync with NetBSD from 1999.05.24 (there is a reason for this date)
Mostly cleanups, but also a few improvements to pagedaemon for better
handling of low memory and/or low swap conditions.

add OpenBSD tags

Import of uvm from NetBSD. Some local changes, some code disabled

Introduce a dummy uvm_obj_destroy() interface. This function will be
used in the near future (by mpi@) to improve the locking for uvm objects.
Introducing this function now will me allow me to call it in the
appropriate place in the drm code.

ok mpi@, jsg@

Introduce dummy pagers for 'special' subsystems using UVM objects.

Some pmaps (x86, hppa) and the buffer cache rely on UVM objects to allocate
and manipulate pages. These objects should not be manipulated by uvm_fault()
and do not currently require the same locking enforcement.

Use the dummy pagers to explicitly document which UVM functions are meant to
manipulate UVM objects (uobj) that do not need the upcoming `vmobjlock' and
instead still rely on the KERNEL_LOCK().

Tested by many as part of a larger diff.

ok kettenis@, beck@

Change the prefix of UVM object functions to match NetBSD's.

For example uvm_objinit() becomes uvm_obj_init(). Reduce differences
between the trees and help porting new functions needed for UVM object
locking.

No functionnal change.

Use a macro to assert that given uobjs correspond to anonymous objects.

Reduce the difference with NetBSD.

ok kettenis@

Constify and use C99 initializer for "struct uvm_pagerops".

While here put some KERNEL_ASSERT_LOCKED() in the functions called from
the page fault handler. The removal of locking of `uobj' will need to be
revisited and these are good indicator that something is missing and that
many comments are lying.

ok kettenis

Add uvm_objfree function to free all pages in a uvm_obj in one go.
Use this in the buffer cache to free all the pages from a buffer,
resulting in a considerable speedup when throwing away pages from
the buffer cache.

Lots of work done with mlarkin and kettenis

ok kettinis@ deraadt@

move the vm_page struct from being stored in RB macro trees to RBT functions

vm_page structs go into three trees, uvm_objtree, uvm_pmr_addr, and
uvm_pmr_size. all these have been moved to RBT code.

this should give us a decent chunk of code space back.

Chuck Cranor rescinded clauses in his license
on the 2nd of February 2011 in NetBSD.

http://marc.info/?l=netbsd-source-changes&m=129658899212732&w=2
http://marc.info/?l=netbsd-source-changes&m=129659095515558&w=2
http://marc.info/?l=netbsd-source-changes&m=129659157916514&w=2
http://marc.info/?l=netbsd-source-changes&m=129665962324372&w=2
http://marc.info/?l=netbsd-source-changes&m=129666033625342&w=2
http://marc.info/?l=netbsd-source-changes&m=129666052825545&w=2
http://marc.info/?l=netbsd-source-changes&m=129666922906480&w=2
http://marc.info/?l=netbsd-source-changes&m=129667725518082&w=2

Fix some potential integer overflows caused by converting a page number into
an offset/size/address by shifting by PAGE_SHIFT. Make uvm_objwrire/unwire
use voff_t instead of off_t. The former is the right type here even if it is
equivalent to the latter.

Inspired by a somewhat similar changes in Bitrig.

ok deraadt@, guenther@

remove simple_locks from uvm code. ok beck deraadt

fix typos; while here, improve spacing in comments.

changes to libevent and zlib headers sent to the upstream maintainers.

ok jmc@ (for typos), millert@

Right now, if anything internal changes with a uvm object, diverse
places in the tree need to be touched to update the object
initialisation with respect to that.

So, make a function (uvm_initobj) that takes the refcount, object and
pager ops and does this initialisation for us. This should save on
maintainance in the future.

looked good to fgs@. Tedu complained about the British spelling but OKed
it anyway.

re-add uvm_objwire and uvm_objunwire. needed for intel GEM support.

It was backed out as part of the date-based revert after c2k9.

"you can commit that" kettenis@

original diff oked by ariane@, art@.

reintroduce the uvm_tree commit.

Now instead of the global object hashtable, we have a per object tree.

Testing shows no performance difference and a slight code shrink. OTOH when
locking is more fine grained this should be faster due to lock contention on
uvm.hashlock.

ok thib@, art@.

date based reversion of uvm to the 4th May.

More backouts in line with previous ones, this appears to bring us back to a
stable condition.

A machine forced to 64mb of ram cycled 10GB through swap with this diff
and is still running as I type this. Other tests by ariane@ and thib@
also seem to show that it's alright.

ok deraadt@, thib@, ariane@

Backout all changes to uvm after pmemrange (which will be backed out
separately).

a change at or just before the hackathon has either exposed or added a
very very nasty memory corruption bug that is giving us hell right now.
So in the interest of kernel stability these diffs are being backed out
until such a time as that corruption bug has been found and squashed,
then the ones that are proven good may slowly return.

a quick hitlist of the main commits this backs out:

mine:
uvm_objwire
the lock change in uvm_swap.c
using trees for uvm objects instead of the hash
removing the pgo_releasepg callback.

art@'s:
putting pmap_page_protect(VM_PROT_NONE) in uvm_pagedeactivate() since
all callers called that just prior anyway.

ok beck@, ariane@.

prompted by deraadt@.

Add uvm_objwire() and uvm_objunwire(), I need this for some of my crazy
shitz.

Code mostly from netbsd with some tweaks from me. The loaning case is
specifcically if 0ed out right now because we do not do loaning.

ok ariane@, art@.

Instead of the global hash table with the terrible hashfunction and a
global lock, switch the uvm object pages to being kept in a per-object
RB_TREE. Right now this is approximately the same speed, but cleaner.
When biglock usage is reduced this will improve concurrency due to lock
contention..

ok beck@ art@. Thanks to jasper for the speed testing.

Instead of managing pages for intrsafe maps in special objects (aka.
kmem_object) just so that we can remove them, just use pmap_extract
to get the pages to free and simplify a lot of code to not deal with
the list of intrsafe maps, intrsafe objects, etc.

miod@ ok

- Make a UVM_OBJ_IS_DEVICE macro.
- Use it to skip device mappings while dumping core.
- Ignore EFAULT errors while dumping core since they can happen
even for valid mappings. Just skip that part of the core file and
let it get automagically zero-filled.

This fixes the broken X core dumps that people have been seeing and also
fixes some other potential problems that could prevent core dumps (mmaps
beyond EOF, etc.).

tedu@ ok

UBC was a disaster. It worked very good when it worked, but on some
machines or some configurations or in some phase of the moon (we actually
don't know when or why) files disappeared. Since we've not been able to
track down the problem in two weeks intense debugging and we need -current
to be stable, back out everything to a state it had before UBC.

We apologise for the inconvenience.

branches: 1.7.2;
Sync in more uvm from NetBSD. Mostly just cosmetic stuff.
Contains also support for page coloring.

Bring in more changes from NetBSD. Mostly pagedaemon improvements.

$OpenBSD$

Bring in some new UVM code from NetBSD (not current).

- Introduce a new type of map that are interrupt safe and never allow faults
in them. mb_map and kmem_map are made intrsafe.
- Add "access protection" to uvm_vslock (to be passed down to uvm_fault and
later to pmap_enter).
- madvise(2) now works.
- various cleanups.

branches: 1.3.4;
sync with NetBSD from 1999.05.24 (there is a reason for this date)
Mostly cleanups, but also a few improvements to pagedaemon for better
handling of low memory and/or low swap conditions.

add OpenBSD tags

Import of uvm from NetBSD. Some local changes, some code disabled

Introduce dummy pagers for 'special' subsystems using UVM objects.

Some pmaps (x86, hppa) and the buffer cache rely on UVM objects to allocate
and manipulate pages. These objects should not be manipulated by uvm_fault()
and do not currently require the same locking enforcement.

Use the dummy pagers to explicitly document which UVM functions are meant to
manipulate UVM objects (uobj) that do not need the upcoming `vmobjlock' and
instead still rely on the KERNEL_LOCK().

Tested by many as part of a larger diff.

ok kettenis@, beck@

Change the prefix of UVM object functions to match NetBSD's.

For example uvm_objinit() becomes uvm_obj_init(). Reduce differences
between the trees and help porting new functions needed for UVM object
locking.

No functionnal change.

Use a macro to assert that given uobjs correspond to anonymous objects.

Reduce the difference with NetBSD.

ok kettenis@

Constify and use C99 initializer for "struct uvm_pagerops".

While here put some KERNEL_ASSERT_LOCKED() in the functions called from
the page fault handler. The removal of locking of `uobj' will need to be
revisited and these are good indicator that something is missing and that
many comments are lying.

ok kettenis

Add uvm_objfree function to free all pages in a uvm_obj in one go.
Use this in the buffer cache to free all the pages from a buffer,
resulting in a considerable speedup when throwing away pages from
the buffer cache.

Lots of work done with mlarkin and kettenis

ok kettinis@ deraadt@

move the vm_page struct from being stored in RB macro trees to RBT functions

vm_page structs go into three trees, uvm_objtree, uvm_pmr_addr, and
uvm_pmr_size. all these have been moved to RBT code.

this should give us a decent chunk of code space back.

Chuck Cranor rescinded clauses in his license
on the 2nd of February 2011 in NetBSD.

http://marc.info/?l=netbsd-source-changes&m=129658899212732&w=2
http://marc.info/?l=netbsd-source-changes&m=129659095515558&w=2
http://marc.info/?l=netbsd-source-changes&m=129659157916514&w=2
http://marc.info/?l=netbsd-source-changes&m=129665962324372&w=2
http://marc.info/?l=netbsd-source-changes&m=129666033625342&w=2
http://marc.info/?l=netbsd-source-changes&m=129666052825545&w=2
http://marc.info/?l=netbsd-source-changes&m=129666922906480&w=2
http://marc.info/?l=netbsd-source-changes&m=129667725518082&w=2

Fix some potential integer overflows caused by converting a page number into
an offset/size/address by shifting by PAGE_SHIFT. Make uvm_objwrire/unwire
use voff_t instead of off_t. The former is the right type here even if it is
equivalent to the latter.

Inspired by a somewhat similar changes in Bitrig.

ok deraadt@, guenther@

remove simple_locks from uvm code. ok beck deraadt

fix typos; while here, improve spacing in comments.

changes to libevent and zlib headers sent to the upstream maintainers.

ok jmc@ (for typos), millert@

Right now, if anything internal changes with a uvm object, diverse
places in the tree need to be touched to update the object
initialisation with respect to that.

So, make a function (uvm_initobj) that takes the refcount, object and
pager ops and does this initialisation for us. This should save on
maintainance in the future.

looked good to fgs@. Tedu complained about the British spelling but OKed
it anyway.

re-add uvm_objwire and uvm_objunwire. needed for intel GEM support.

It was backed out as part of the date-based revert after c2k9.

"you can commit that" kettenis@

original diff oked by ariane@, art@.

reintroduce the uvm_tree commit.

Now instead of the global object hashtable, we have a per object tree.

Testing shows no performance difference and a slight code shrink. OTOH when
locking is more fine grained this should be faster due to lock contention on
uvm.hashlock.

ok thib@, art@.

date based reversion of uvm to the 4th May.

More backouts in line with previous ones, this appears to bring us back to a
stable condition.

A machine forced to 64mb of ram cycled 10GB through swap with this diff
and is still running as I type this. Other tests by ariane@ and thib@
also seem to show that it's alright.

ok deraadt@, thib@, ariane@

Backout all changes to uvm after pmemrange (which will be backed out
separately).

a change at or just before the hackathon has either exposed or added a
very very nasty memory corruption bug that is giving us hell right now.
So in the interest of kernel stability these diffs are being backed out
until such a time as that corruption bug has been found and squashed,
then the ones that are proven good may slowly return.

a quick hitlist of the main commits this backs out:

mine:
uvm_objwire
the lock change in uvm_swap.c
using trees for uvm objects instead of the hash
removing the pgo_releasepg callback.

art@'s:
putting pmap_page_protect(VM_PROT_NONE) in uvm_pagedeactivate() since
all callers called that just prior anyway.

ok beck@, ariane@.

prompted by deraadt@.

Add uvm_objwire() and uvm_objunwire(), I need this for some of my crazy
shitz.

Code mostly from netbsd with some tweaks from me. The loaning case is
specifcically if 0ed out right now because we do not do loaning.

ok ariane@, art@.

Instead of the global hash table with the terrible hashfunction and a
global lock, switch the uvm object pages to being kept in a per-object
RB_TREE. Right now this is approximately the same speed, but cleaner.
When biglock usage is reduced this will improve concurrency due to lock
contention..

ok beck@ art@. Thanks to jasper for the speed testing.

Instead of managing pages for intrsafe maps in special objects (aka.
kmem_object) just so that we can remove them, just use pmap_extract
to get the pages to free and simplify a lot of code to not deal with
the list of intrsafe maps, intrsafe objects, etc.

miod@ ok

- Make a UVM_OBJ_IS_DEVICE macro.
- Use it to skip device mappings while dumping core.
- Ignore EFAULT errors while dumping core since they can happen
even for valid mappings. Just skip that part of the core file and
let it get automagically zero-filled.

This fixes the broken X core dumps that people have been seeing and also
fixes some other potential problems that could prevent core dumps (mmaps
beyond EOF, etc.).

tedu@ ok

UBC was a disaster. It worked very good when it worked, but on some
machines or some configurations or in some phase of the moon (we actually
don't know when or why) files disappeared. Since we've not been able to
track down the problem in two weeks intense debugging and we need -current
to be stable, back out everything to a state it had before UBC.

We apologise for the inconvenience.

branches: 1.7.2;
Sync in more uvm from NetBSD. Mostly just cosmetic stuff.
Contains also support for page coloring.

Bring in more changes from NetBSD. Mostly pagedaemon improvements.

$OpenBSD$

Bring in some new UVM code from NetBSD (not current).

- Introduce a new type of map that are interrupt safe and never allow faults
in them. mb_map and kmem_map are made intrsafe.
- Add "access protection" to uvm_vslock (to be passed down to uvm_fault and
later to pmap_enter).
- madvise(2) now works.
- various cleanups.

branches: 1.3.4;
sync with NetBSD from 1999.05.24 (there is a reason for this date)
Mostly cleanups, but also a few improvements to pagedaemon for better
handling of low memory and/or low swap conditions.

add OpenBSD tags

Import of uvm from NetBSD. Some local changes, some code disabled

Change the prefix of UVM object functions to match NetBSD's.

For example uvm_objinit() becomes uvm_obj_init(). Reduce differences
between the trees and help porting new functions needed for UVM object
locking.

No functionnal change.

Use a macro to assert that given uobjs correspond to anonymous objects.

Reduce the difference with NetBSD.

ok kettenis@

Constify and use C99 initializer for "struct uvm_pagerops".

While here put some KERNEL_ASSERT_LOCKED() in the functions called from
the page fault handler. The removal of locking of `uobj' will need to be
revisited and these are good indicator that something is missing and that
many comments are lying.

ok kettenis

Add uvm_objfree function to free all pages in a uvm_obj in one go.
Use this in the buffer cache to free all the pages from a buffer,
resulting in a considerable speedup when throwing away pages from
the buffer cache.

Lots of work done with mlarkin and kettenis

ok kettinis@ deraadt@

move the vm_page struct from being stored in RB macro trees to RBT functions

vm_page structs go into three trees, uvm_objtree, uvm_pmr_addr, and
uvm_pmr_size. all these have been moved to RBT code.

this should give us a decent chunk of code space back.

Chuck Cranor rescinded clauses in his license
on the 2nd of February 2011 in NetBSD.

http://marc.info/?l=netbsd-source-changes&m=129658899212732&w=2
http://marc.info/?l=netbsd-source-changes&m=129659095515558&w=2
http://marc.info/?l=netbsd-source-changes&m=129659157916514&w=2
http://marc.info/?l=netbsd-source-changes&m=129665962324372&w=2
http://marc.info/?l=netbsd-source-changes&m=129666033625342&w=2
http://marc.info/?l=netbsd-source-changes&m=129666052825545&w=2
http://marc.info/?l=netbsd-source-changes&m=129666922906480&w=2
http://marc.info/?l=netbsd-source-changes&m=129667725518082&w=2

Fix some potential integer overflows caused by converting a page number into
an offset/size/address by shifting by PAGE_SHIFT. Make uvm_objwrire/unwire
use voff_t instead of off_t. The former is the right type here even if it is
equivalent to the latter.

Inspired by a somewhat similar changes in Bitrig.

ok deraadt@, guenther@

remove simple_locks from uvm code. ok beck deraadt

fix typos; while here, improve spacing in comments.

changes to libevent and zlib headers sent to the upstream maintainers.

ok jmc@ (for typos), millert@

Right now, if anything internal changes with a uvm object, diverse
places in the tree need to be touched to update the object
initialisation with respect to that.

So, make a function (uvm_initobj) that takes the refcount, object and
pager ops and does this initialisation for us. This should save on
maintainance in the future.

looked good to fgs@. Tedu complained about the British spelling but OKed
it anyway.

re-add uvm_objwire and uvm_objunwire. needed for intel GEM support.

It was backed out as part of the date-based revert after c2k9.

"you can commit that" kettenis@

original diff oked by ariane@, art@.

reintroduce the uvm_tree commit.

Now instead of the global object hashtable, we have a per object tree.

Testing shows no performance difference and a slight code shrink. OTOH when
locking is more fine grained this should be faster due to lock contention on
uvm.hashlock.

ok thib@, art@.

date based reversion of uvm to the 4th May.

More backouts in line with previous ones, this appears to bring us back to a
stable condition.

A machine forced to 64mb of ram cycled 10GB through swap with this diff
and is still running as I type this. Other tests by ariane@ and thib@
also seem to show that it's alright.

ok deraadt@, thib@, ariane@

Backout all changes to uvm after pmemrange (which will be backed out
separately).

a change at or just before the hackathon has either exposed or added a
very very nasty memory corruption bug that is giving us hell right now.
So in the interest of kernel stability these diffs are being backed out
until such a time as that corruption bug has been found and squashed,
then the ones that are proven good may slowly return.

a quick hitlist of the main commits this backs out:

mine:
uvm_objwire
the lock change in uvm_swap.c
using trees for uvm objects instead of the hash
removing the pgo_releasepg callback.

art@'s:
putting pmap_page_protect(VM_PROT_NONE) in uvm_pagedeactivate() since
all callers called that just prior anyway.

ok beck@, ariane@.

prompted by deraadt@.

Add uvm_objwire() and uvm_objunwire(), I need this for some of my crazy
shitz.

Code mostly from netbsd with some tweaks from me. The loaning case is
specifcically if 0ed out right now because we do not do loaning.

ok ariane@, art@.

Instead of the global hash table with the terrible hashfunction and a
global lock, switch the uvm object pages to being kept in a per-object
RB_TREE. Right now this is approximately the same speed, but cleaner.
When biglock usage is reduced this will improve concurrency due to lock
contention..

ok beck@ art@. Thanks to jasper for the speed testing.

Instead of managing pages for intrsafe maps in special objects (aka.
kmem_object) just so that we can remove them, just use pmap_extract
to get the pages to free and simplify a lot of code to not deal with
the list of intrsafe maps, intrsafe objects, etc.

miod@ ok

- Make a UVM_OBJ_IS_DEVICE macro.
- Use it to skip device mappings while dumping core.
- Ignore EFAULT errors while dumping core since they can happen
even for valid mappings. Just skip that part of the core file and
let it get automagically zero-filled.

This fixes the broken X core dumps that people have been seeing and also
fixes some other potential problems that could prevent core dumps (mmaps
beyond EOF, etc.).

tedu@ ok

UBC was a disaster. It worked very good when it worked, but on some
machines or some configurations or in some phase of the moon (we actually
don't know when or why) files disappeared. Since we've not been able to
track down the problem in two weeks intense debugging and we need -current
to be stable, back out everything to a state it had before UBC.

We apologise for the inconvenience.

branches: 1.7.2;
Sync in more uvm from NetBSD. Mostly just cosmetic stuff.
Contains also support for page coloring.

Bring in more changes from NetBSD. Mostly pagedaemon improvements.

$OpenBSD$

Bring in some new UVM code from NetBSD (not current).

- Introduce a new type of map that are interrupt safe and never allow faults
in them. mb_map and kmem_map are made intrsafe.
- Add "access protection" to uvm_vslock (to be passed down to uvm_fault and
later to pmap_enter).
- madvise(2) now works.
- various cleanups.

branches: 1.3.4;
sync with NetBSD from 1999.05.24 (there is a reason for this date)
Mostly cleanups, but also a few improvements to pagedaemon for better
handling of low memory and/or low swap conditions.

add OpenBSD tags

Import of uvm from NetBSD. Some local changes, some code disabled

Constify and use C99 initializer for "struct uvm_pagerops".

While here put some KERNEL_ASSERT_LOCKED() in the functions called from
the page fault handler. The removal of locking of `uobj' will need to be
revisited and these are good indicator that something is missing and that
many comments are lying.

ok kettenis

Add uvm_objfree function to free all pages in a uvm_obj in one go.
Use this in the buffer cache to free all the pages from a buffer,
resulting in a considerable speedup when throwing away pages from
the buffer cache.

Lots of work done with mlarkin and kettenis

ok kettinis@ deraadt@

move the vm_page struct from being stored in RB macro trees to RBT functions

vm_page structs go into three trees, uvm_objtree, uvm_pmr_addr, and
uvm_pmr_size. all these have been moved to RBT code.

this should give us a decent chunk of code space back.

Chuck Cranor rescinded clauses in his license
on the 2nd of February 2011 in NetBSD.

http://marc.info/?l=netbsd-source-changes&m=129658899212732&w=2
http://marc.info/?l=netbsd-source-changes&m=129659095515558&w=2
http://marc.info/?l=netbsd-source-changes&m=129659157916514&w=2
http://marc.info/?l=netbsd-source-changes&m=129665962324372&w=2
http://marc.info/?l=netbsd-source-changes&m=129666033625342&w=2
http://marc.info/?l=netbsd-source-changes&m=129666052825545&w=2
http://marc.info/?l=netbsd-source-changes&m=129666922906480&w=2
http://marc.info/?l=netbsd-source-changes&m=129667725518082&w=2

Fix some potential integer overflows caused by converting a page number into
an offset/size/address by shifting by PAGE_SHIFT. Make uvm_objwrire/unwire
use voff_t instead of off_t. The former is the right type here even if it is
equivalent to the latter.

Inspired by a somewhat similar changes in Bitrig.

ok deraadt@, guenther@

remove simple_locks from uvm code. ok beck deraadt

fix typos; while here, improve spacing in comments.

changes to libevent and zlib headers sent to the upstream maintainers.

ok jmc@ (for typos), millert@

Right now, if anything internal changes with a uvm object, diverse
places in the tree need to be touched to update the object
initialisation with respect to that.

So, make a function (uvm_initobj) that takes the refcount, object and
pager ops and does this initialisation for us. This should save on
maintainance in the future.

looked good to fgs@. Tedu complained about the British spelling but OKed
it anyway.

re-add uvm_objwire and uvm_objunwire. needed for intel GEM support.

It was backed out as part of the date-based revert after c2k9.

"you can commit that" kettenis@

original diff oked by ariane@, art@.

reintroduce the uvm_tree commit.

Now instead of the global object hashtable, we have a per object tree.

Testing shows no performance difference and a slight code shrink. OTOH when
locking is more fine grained this should be faster due to lock contention on
uvm.hashlock.

ok thib@, art@.

date based reversion of uvm to the 4th May.

More backouts in line with previous ones, this appears to bring us back to a
stable condition.

A machine forced to 64mb of ram cycled 10GB through swap with this diff
and is still running as I type this. Other tests by ariane@ and thib@
also seem to show that it's alright.

ok deraadt@, thib@, ariane@

Backout all changes to uvm after pmemrange (which will be backed out
separately).

a change at or just before the hackathon has either exposed or added a
very very nasty memory corruption bug that is giving us hell right now.
So in the interest of kernel stability these diffs are being backed out
until such a time as that corruption bug has been found and squashed,
then the ones that are proven good may slowly return.

a quick hitlist of the main commits this backs out:

mine:
uvm_objwire
the lock change in uvm_swap.c
using trees for uvm objects instead of the hash
removing the pgo_releasepg callback.

art@'s:
putting pmap_page_protect(VM_PROT_NONE) in uvm_pagedeactivate() since
all callers called that just prior anyway.

ok beck@, ariane@.

prompted by deraadt@.

Add uvm_objwire() and uvm_objunwire(), I need this for some of my crazy
shitz.

Code mostly from netbsd with some tweaks from me. The loaning case is
specifcically if 0ed out right now because we do not do loaning.

ok ariane@, art@.

Instead of the global hash table with the terrible hashfunction and a
global lock, switch the uvm object pages to being kept in a per-object
RB_TREE. Right now this is approximately the same speed, but cleaner.
When biglock usage is reduced this will improve concurrency due to lock
contention..

ok beck@ art@. Thanks to jasper for the speed testing.

Instead of managing pages for intrsafe maps in special objects (aka.
kmem_object) just so that we can remove them, just use pmap_extract
to get the pages to free and simplify a lot of code to not deal with
the list of intrsafe maps, intrsafe objects, etc.

miod@ ok

- Make a UVM_OBJ_IS_DEVICE macro.
- Use it to skip device mappings while dumping core.
- Ignore EFAULT errors while dumping core since they can happen
even for valid mappings. Just skip that part of the core file and
let it get automagically zero-filled.

This fixes the broken X core dumps that people have been seeing and also
fixes some other potential problems that could prevent core dumps (mmaps
beyond EOF, etc.).

tedu@ ok

UBC was a disaster. It worked very good when it worked, but on some
machines or some configurations or in some phase of the moon (we actually
don't know when or why) files disappeared. Since we've not been able to
track down the problem in two weeks intense debugging and we need -current
to be stable, back out everything to a state it had before UBC.

We apologise for the inconvenience.

branches: 1.7.2;
Sync in more uvm from NetBSD. Mostly just cosmetic stuff.
Contains also support for page coloring.

Bring in more changes from NetBSD. Mostly pagedaemon improvements.

$OpenBSD$

Bring in some new UVM code from NetBSD (not current).

- Introduce a new type of map that are interrupt safe and never allow faults
in them. mb_map and kmem_map are made intrsafe.
- Add "access protection" to uvm_vslock (to be passed down to uvm_fault and
later to pmap_enter).
- madvise(2) now works.
- various cleanups.

branches: 1.3.4;
sync with NetBSD from 1999.05.24 (there is a reason for this date)
Mostly cleanups, but also a few improvements to pagedaemon for better
handling of low memory and/or low swap conditions.

add OpenBSD tags

Import of uvm from NetBSD. Some local changes, some code disabled

Add uvm_objfree function to free all pages in a uvm_obj in one go.
Use this in the buffer cache to free all the pages from a buffer,
resulting in a considerable speedup when throwing away pages from
the buffer cache.

Lots of work done with mlarkin and kettenis

ok kettinis@ deraadt@

move the vm_page struct from being stored in RB macro trees to RBT functions

vm_page structs go into three trees, uvm_objtree, uvm_pmr_addr, and
uvm_pmr_size. all these have been moved to RBT code.

this should give us a decent chunk of code space back.

Chuck Cranor rescinded clauses in his license
on the 2nd of February 2011 in NetBSD.

http://marc.info/?l=netbsd-source-changes&m=129658899212732&w=2
http://marc.info/?l=netbsd-source-changes&m=129659095515558&w=2
http://marc.info/?l=netbsd-source-changes&m=129659157916514&w=2
http://marc.info/?l=netbsd-source-changes&m=129665962324372&w=2
http://marc.info/?l=netbsd-source-changes&m=129666033625342&w=2
http://marc.info/?l=netbsd-source-changes&m=129666052825545&w=2
http://marc.info/?l=netbsd-source-changes&m=129666922906480&w=2
http://marc.info/?l=netbsd-source-changes&m=129667725518082&w=2

Fix some potential integer overflows caused by converting a page number into
an offset/size/address by shifting by PAGE_SHIFT. Make uvm_objwrire/unwire
use voff_t instead of off_t. The former is the right type here even if it is
equivalent to the latter.

Inspired by a somewhat similar changes in Bitrig.

ok deraadt@, guenther@

remove simple_locks from uvm code. ok beck deraadt

fix typos; while here, improve spacing in comments.

changes to libevent and zlib headers sent to the upstream maintainers.

ok jmc@ (for typos), millert@

Right now, if anything internal changes with a uvm object, diverse
places in the tree need to be touched to update the object
initialisation with respect to that.

So, make a function (uvm_initobj) that takes the refcount, object and
pager ops and does this initialisation for us. This should save on
maintainance in the future.

looked good to fgs@. Tedu complained about the British spelling but OKed
it anyway.

re-add uvm_objwire and uvm_objunwire. needed for intel GEM support.

It was backed out as part of the date-based revert after c2k9.

"you can commit that" kettenis@

original diff oked by ariane@, art@.

reintroduce the uvm_tree commit.

Now instead of the global object hashtable, we have a per object tree.

Testing shows no performance difference and a slight code shrink. OTOH when
locking is more fine grained this should be faster due to lock contention on
uvm.hashlock.

ok thib@, art@.

date based reversion of uvm to the 4th May.

More backouts in line with previous ones, this appears to bring us back to a
stable condition.

A machine forced to 64mb of ram cycled 10GB through swap with this diff
and is still running as I type this. Other tests by ariane@ and thib@
also seem to show that it's alright.

ok deraadt@, thib@, ariane@

Backout all changes to uvm after pmemrange (which will be backed out
separately).

a change at or just before the hackathon has either exposed or added a
very very nasty memory corruption bug that is giving us hell right now.
So in the interest of kernel stability these diffs are being backed out
until such a time as that corruption bug has been found and squashed,
then the ones that are proven good may slowly return.

a quick hitlist of the main commits this backs out:

mine:
uvm_objwire
the lock change in uvm_swap.c
using trees for uvm objects instead of the hash
removing the pgo_releasepg callback.

art@'s:
putting pmap_page_protect(VM_PROT_NONE) in uvm_pagedeactivate() since
all callers called that just prior anyway.

ok beck@, ariane@.

prompted by deraadt@.

Add uvm_objwire() and uvm_objunwire(), I need this for some of my crazy
shitz.

Code mostly from netbsd with some tweaks from me. The loaning case is
specifcically if 0ed out right now because we do not do loaning.

ok ariane@, art@.

Instead of the global hash table with the terrible hashfunction and a
global lock, switch the uvm object pages to being kept in a per-object
RB_TREE. Right now this is approximately the same speed, but cleaner.
When biglock usage is reduced this will improve concurrency due to lock
contention..

ok beck@ art@. Thanks to jasper for the speed testing.

Instead of managing pages for intrsafe maps in special objects (aka.
kmem_object) just so that we can remove them, just use pmap_extract
to get the pages to free and simplify a lot of code to not deal with
the list of intrsafe maps, intrsafe objects, etc.

miod@ ok

- Make a UVM_OBJ_IS_DEVICE macro.
- Use it to skip device mappings while dumping core.
- Ignore EFAULT errors while dumping core since they can happen
even for valid mappings. Just skip that part of the core file and
let it get automagically zero-filled.

This fixes the broken X core dumps that people have been seeing and also
fixes some other potential problems that could prevent core dumps (mmaps
beyond EOF, etc.).

tedu@ ok

UBC was a disaster. It worked very good when it worked, but on some
machines or some configurations or in some phase of the moon (we actually
don't know when or why) files disappeared. Since we've not been able to
track down the problem in two weeks intense debugging and we need -current
to be stable, back out everything to a state it had before UBC.

We apologise for the inconvenience.

branches: 1.7.2;
Sync in more uvm from NetBSD. Mostly just cosmetic stuff.
Contains also support for page coloring.

Bring in more changes from NetBSD. Mostly pagedaemon improvements.

$OpenBSD$

Bring in some new UVM code from NetBSD (not current).

- Introduce a new type of map that are interrupt safe and never allow faults
in them. mb_map and kmem_map are made intrsafe.
- Add "access protection" to uvm_vslock (to be passed down to uvm_fault and
later to pmap_enter).
- madvise(2) now works.
- various cleanups.

branches: 1.3.4;
sync with NetBSD from 1999.05.24 (there is a reason for this date)
Mostly cleanups, but also a few improvements to pagedaemon for better
handling of low memory and/or low swap conditions.

add OpenBSD tags

Import of uvm from NetBSD. Some local changes, some code disabled

move the vm_page struct from being stored in RB macro trees to RBT functions

vm_page structs go into three trees, uvm_objtree, uvm_pmr_addr, and
uvm_pmr_size. all these have been moved to RBT code.

this should give us a decent chunk of code space back.

Chuck Cranor rescinded clauses in his license
on the 2nd of February 2011 in NetBSD.

http://marc.info/?l=netbsd-source-changes&m=129658899212732&w=2
http://marc.info/?l=netbsd-source-changes&m=129659095515558&w=2
http://marc.info/?l=netbsd-source-changes&m=129659157916514&w=2
http://marc.info/?l=netbsd-source-changes&m=129665962324372&w=2
http://marc.info/?l=netbsd-source-changes&m=129666033625342&w=2
http://marc.info/?l=netbsd-source-changes&m=129666052825545&w=2
http://marc.info/?l=netbsd-source-changes&m=129666922906480&w=2
http://marc.info/?l=netbsd-source-changes&m=129667725518082&w=2

Fix some potential integer overflows caused by converting a page number into
an offset/size/address by shifting by PAGE_SHIFT. Make uvm_objwrire/unwire
use voff_t instead of off_t. The former is the right type here even if it is
equivalent to the latter.

Inspired by a somewhat similar changes in Bitrig.

ok deraadt@, guenther@

remove simple_locks from uvm code. ok beck deraadt

fix typos; while here, improve spacing in comments.

changes to libevent and zlib headers sent to the upstream maintainers.

ok jmc@ (for typos), millert@

Right now, if anything internal changes with a uvm object, diverse
places in the tree need to be touched to update the object
initialisation with respect to that.

So, make a function (uvm_initobj) that takes the refcount, object and
pager ops and does this initialisation for us. This should save on
maintainance in the future.

looked good to fgs@. Tedu complained about the British spelling but OKed
it anyway.

re-add uvm_objwire and uvm_objunwire. needed for intel GEM support.

It was backed out as part of the date-based revert after c2k9.

"you can commit that" kettenis@

original diff oked by ariane@, art@.

reintroduce the uvm_tree commit.

Now instead of the global object hashtable, we have a per object tree.

Testing shows no performance difference and a slight code shrink. OTOH when
locking is more fine grained this should be faster due to lock contention on
uvm.hashlock.

ok thib@, art@.

date based reversion of uvm to the 4th May.

More backouts in line with previous ones, this appears to bring us back to a
stable condition.

A machine forced to 64mb of ram cycled 10GB through swap with this diff
and is still running as I type this. Other tests by ariane@ and thib@
also seem to show that it's alright.

ok deraadt@, thib@, ariane@

Backout all changes to uvm after pmemrange (which will be backed out
separately).

a change at or just before the hackathon has either exposed or added a
very very nasty memory corruption bug that is giving us hell right now.
So in the interest of kernel stability these diffs are being backed out
until such a time as that corruption bug has been found and squashed,
then the ones that are proven good may slowly return.

a quick hitlist of the main commits this backs out:

mine:
uvm_objwire
the lock change in uvm_swap.c
using trees for uvm objects instead of the hash
removing the pgo_releasepg callback.

art@'s:
putting pmap_page_protect(VM_PROT_NONE) in uvm_pagedeactivate() since
all callers called that just prior anyway.

ok beck@, ariane@.

prompted by deraadt@.

Add uvm_objwire() and uvm_objunwire(), I need this for some of my crazy
shitz.

Code mostly from netbsd with some tweaks from me. The loaning case is
specifcically if 0ed out right now because we do not do loaning.

ok ariane@, art@.

Instead of the global hash table with the terrible hashfunction and a
global lock, switch the uvm object pages to being kept in a per-object
RB_TREE. Right now this is approximately the same speed, but cleaner.
When biglock usage is reduced this will improve concurrency due to lock
contention..

ok beck@ art@. Thanks to jasper for the speed testing.

Instead of managing pages for intrsafe maps in special objects (aka.
kmem_object) just so that we can remove them, just use pmap_extract
to get the pages to free and simplify a lot of code to not deal with
the list of intrsafe maps, intrsafe objects, etc.

miod@ ok

- Make a UVM_OBJ_IS_DEVICE macro.
- Use it to skip device mappings while dumping core.
- Ignore EFAULT errors while dumping core since they can happen
even for valid mappings. Just skip that part of the core file and
let it get automagically zero-filled.

This fixes the broken X core dumps that people have been seeing and also
fixes some other potential problems that could prevent core dumps (mmaps
beyond EOF, etc.).

tedu@ ok

UBC was a disaster. It worked very good when it worked, but on some
machines or some configurations or in some phase of the moon (we actually
don't know when or why) files disappeared. Since we've not been able to
track down the problem in two weeks intense debugging and we need -current
to be stable, back out everything to a state it had before UBC.

We apologise for the inconvenience.

branches: 1.7.2;
Sync in more uvm from NetBSD. Mostly just cosmetic stuff.
Contains also support for page coloring.

Bring in more changes from NetBSD. Mostly pagedaemon improvements.

$OpenBSD$

Bring in some new UVM code from NetBSD (not current).

- Introduce a new type of map that are interrupt safe and never allow faults
in them. mb_map and kmem_map are made intrsafe.
- Add "access protection" to uvm_vslock (to be passed down to uvm_fault and
later to pmap_enter).
- madvise(2) now works.
- various cleanups.

branches: 1.3.4;
sync with NetBSD from 1999.05.24 (there is a reason for this date)
Mostly cleanups, but also a few improvements to pagedaemon for better
handling of low memory and/or low swap conditions.

add OpenBSD tags

Import of uvm from NetBSD. Some local changes, some code disabled