CVS log for src/sys/uvm/uvm_device.c

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Keyword substitution: kv
Default branch: MAIN

uvm: CTASSERT about MIN_PAGE_SIZE, which is constant.

Convert CTASSERT(9) for PAGE_{SIZE,MASK} into KASSERT(9).

They are not compile-time constants for sparc.

kern: Work around spurious -Wtype-limits warnings.

This useless garbage warning is apparently designed to make it
painful to write portable safe arithmetic and I think we ought to
just disable it.

mmap(2): Guarantee two's-complement wraparound for D_NEGOFFSAFE.

XXX Not sure this should be allowed at all, but this way we don't
change the semantics of the existing code which was written under
essentially the assumption of -fwrapv.

uvm/uvm_device.c: Sprinkle KNF.

mmap(2): Prohibit overflowing offsets for non-D_NEGOFFSAFE devices.

Reported-by: syzbot+d5a96e7a0ebbd0b76dfc@syzkaller.appspotmail.com

uvm(9): fo_mmap caller guarantees positive size.

No functional change intended, just sprinkling assertions to make it
clearer.

driver(9): New types dev_*_t for device driver devsw operations.

These will serve to replace the archaic and kludgey dev_type_* macros
which should've been typedefs all along.

Sync with HEAD.

Consistently use %#jx instead of 0x%jx or just %jx in UVMHIST_LOG formats

Consistently use UVMHIST(__func__)

Convert UVMHIST_{CALLED,LOG} into UVMHIST_CALLARGS

Merge changes from current as of 20200406

Sync with head.

0x%#x --> %#x for non-external codes.
Also, stop mixing up 0x%x and %#x in single files as far as possible.

UVM locking changes, proposed on tech-kern:

- Change the lock on uvm_object, vm_amap and vm_anon to be a RW lock.
- Break v_interlock and vmobjlock apart.  v_interlock remains a mutex.
- Do partial PV list locking in the x86 pmap.  Others to follow later.

do not wait for memory in pgo_fault methods, just return ENOMEM
and let the uvm_fault code wait if it is appropriate.

__cacheline_aligned on a lock.

update from HEAD

Pull up following revision(s) (requested by pgoyette in ticket #335):
	share/man/man9/kernhist.9: 1.5-1.8
	sys/arch/acorn26/acorn26/pmap.c: 1.39
	sys/arch/arm/arm32/fault.c: 1.105 via patch
	sys/arch/arm/arm32/pmap.c: 1.350, 1.359
	sys/arch/arm/broadcom/bcm2835_bsc.c: 1.7
	sys/arch/arm/omap/if_cpsw.c: 1.20
	sys/arch/arm/omap/tiotg.c: 1.7
	sys/arch/evbarm/conf/RPI2_INSTALL: 1.3
	sys/dev/ic/sl811hs.c: 1.98
	sys/dev/usb/ehci.c: 1.256
	sys/dev/usb/if_axe.c: 1.83
	sys/dev/usb/motg.c: 1.18
	sys/dev/usb/ohci.c: 1.274
	sys/dev/usb/ucom.c: 1.119
	sys/dev/usb/uhci.c: 1.277
	sys/dev/usb/uhub.c: 1.137
	sys/dev/usb/umass.c: 1.160-1.162
	sys/dev/usb/umass_quirks.c: 1.100
	sys/dev/usb/umass_scsipi.c: 1.55
	sys/dev/usb/usb.c: 1.168
	sys/dev/usb/usb_mem.c: 1.70
	sys/dev/usb/usb_subr.c: 1.221
	sys/dev/usb/usbdi.c: 1.175
	sys/dev/usb/usbdi_util.c: 1.67-1.70
	sys/dev/usb/usbroothub.c: 1.3
	sys/dev/usb/xhci.c: 1.75
	sys/external/bsd/drm2/dist/drm/i915/i915_gem.c: 1.34
	sys/kern/kern_history.c: 1.15
	sys/kern/kern_xxx.c: 1.74
	sys/kern/vfs_bio.c: 1.275-1.276
	sys/miscfs/genfs/genfs_io.c: 1.71
	sys/sys/kernhist.h: 1.21
	sys/ufs/ffs/ffs_balloc.c: 1.63
	sys/ufs/lfs/lfs_vfsops.c: 1.361
	sys/ufs/lfs/ulfs_inode.c: 1.21
	sys/ufs/lfs/ulfs_vnops.c: 1.52
	sys/ufs/ufs/ufs_inode.c: 1.102
	sys/ufs/ufs/ufs_vnops.c: 1.239
	sys/uvm/pmap/pmap.c: 1.37-1.39
	sys/uvm/pmap/pmap_tlb.c: 1.22
	sys/uvm/uvm_amap.c: 1.108
	sys/uvm/uvm_anon.c: 1.64
	sys/uvm/uvm_aobj.c: 1.126
	sys/uvm/uvm_bio.c: 1.91
	sys/uvm/uvm_device.c: 1.66
	sys/uvm/uvm_fault.c: 1.201
	sys/uvm/uvm_km.c: 1.144
	sys/uvm/uvm_loan.c: 1.85
	sys/uvm/uvm_map.c: 1.353
	sys/uvm/uvm_page.c: 1.194
	sys/uvm/uvm_pager.c: 1.111
	sys/uvm/uvm_pdaemon.c: 1.109
	sys/uvm/uvm_swap.c: 1.175
	sys/uvm/uvm_vnode.c: 1.103
	usr.bin/vmstat/vmstat.c: 1.219
Reorder to test for null before null deref in debug code
--
Reorder to test for null before null deref in debug code
--
KNF
--
No need for '\n' in UVMHIST_LOG
--
normalise a BIOHIST log message
--
Update the kernhist(9) kernel history code to address issues identified
in PR kern/52639, as well as some general cleaning-up...
(As proposed on tech-kern@ with additional changes and enhancements.)
Details of changes:
* All history arguments are now stored as uintmax_t values[1], both in
   the kernel and in the structures used for exporting the history data
   to userland via sysctl(9).  This avoids problems on some architectures
   where passing a 64-bit (or larger) value to printf(3) can cause it to
   process the value as multiple arguments.  (This can be particularly
   problematic when printf()'s format string is not a literal, since in
   that case the compiler cannot know how large each argument should be.)
* Update the data structures used for exporting kernel history data to
   include a version number as well as the length of history arguments.
* All [2] existing users of kernhist(9) have had their format strings
   updated.  Each format specifier now includes an explicit length
   modifier 'j' to refer to numeric values of the size of uintmax_t.
* All [2] existing users of kernhist(9) have had their format strings
   updated to replace uses of "%p" with "%#jx", and the pointer
   arguments are now cast to (uintptr_t) before being subsequently cast
   to (uintmax_t).  This is needed to avoid compiler warnings about
   casting "pointer to integer of a different size."
* All [2] existing users of kernhist(9) have had instances of "%s" or
   "%c" format strings replaced with numeric formats; several instances
   of mis-match between format string and argument list have been fixed.
* vmstat(1) has been modified to handle the new size of arguments in the
   history data as exported by sysctl(9).
* vmstat(1) now provides a warning message if the history requested with
   the -u option does not exist (previously, this condition was silently
   ignored, with only a single blank line being printed).
* vmstat(1) now checks the version and argument length included in the
   data exported via sysctl(9) and exits if they do not match the values
   with which vmstat was built.
* The kernhist(9) man-page has been updated to note the additional
   requirements imposed on the format strings, along with several other
   minor changes and enhancements.
[1] It would have been possible to use an explicit length (for example,
     uint64_t) for the history arguments.  But that would require another
     "rototill" of all the users in the future when we add support for an
     architecture that supports a larger size.  Also, the printf(3)
format
     specifiers for explicitly-sized values, such as "%"PRIu64, are much
     more verbose (and less aesthetically appealing, IMHO) than simply
     using "%ju".
[2] I've tried very hard to find "all [the] existing users of
kernhist(9)"
     but it is possible that I've missed some of them.  I would be glad
to
     update any stragglers that anyone identifies.
--
For some reason this single kernel seems to have outgrown its declared
size as a result of the kernhist(9) changes.  Bump the size.
XXX The amount of increase may be excessive - anyone with more detailed
XXX knowledge please feel free to further adjust the value
appropriately.
--
Misssed one cast of pointer --> uintptr_t in previous kernhist(9) commit
--
And yet another one.  :(
--
Use correct mark-up for NetBSD version.
--
More improvements in grammar and readability.
--
Remove a stray '"' (obvious typo) and add a couple of casts that are
probably needed.
--
And replace an instance of "%p" conversion with "%#jx"
--
Whitespace fix. Give Bl tag table a width. Fix Xr.

Update the kernhist(9) kernel history code to address issues identified
in PR kern/52639, as well as some general cleaning-up...

(As proposed on tech-kern@ with additional changes and enhancements.)

Details of changes:

* All history arguments are now stored as uintmax_t values[1], both in
  the kernel and in the structures used for exporting the history data
  to userland via sysctl(9).  This avoids problems on some architectures
  where passing a 64-bit (or larger) value to printf(3) can cause it to
  process the value as multiple arguments.  (This can be particularly
  problematic when printf()'s format string is not a literal, since in
  that case the compiler cannot know how large each argument should be.)

* Update the data structures used for exporting kernel history data to
  include a version number as well as the length of history arguments.

* All [2] existing users of kernhist(9) have had their format strings
  updated.  Each format specifier now includes an explicit length
  modifier 'j' to refer to numeric values of the size of uintmax_t.

* All [2] existing users of kernhist(9) have had their format strings
  updated to replace uses of "%p" with "%#jx", and the pointer
  arguments are now cast to (uintptr_t) before being subsequently cast
  to (uintmax_t).  This is needed to avoid compiler warnings about
  casting "pointer to integer of a different size."

* All [2] existing users of kernhist(9) have had instances of "%s" or
  "%c" format strings replaced with numeric formats; several instances
  of mis-match between format string and argument list have been fixed.

* vmstat(1) has been modified to handle the new size of arguments in the
  history data as exported by sysctl(9).

* vmstat(1) now provides a warning message if the history requested with
  the -u option does not exist (previously, this condition was silently
  ignored, with only a single blank line being printed).

* vmstat(1) now checks the version and argument length included in the
  data exported via sysctl(9) and exits if they do not match the values
  with which vmstat was built.

* The kernhist(9) man-page has been updated to note the additional
  requirements imposed on the format strings, along with several other
  minor changes and enhancements.

[1] It would have been possible to use an explicit length (for example,
    uint64_t) for the history arguments.  But that would require another
    "rototill" of all the users in the future when we add support for an
    architecture that supports a larger size.  Also, the printf(3) format
    specifiers for explicitly-sized values, such as "%"PRIu64, are much
    more verbose (and less aesthetically appealing, IMHO) than simply
    using "%ju".

[2] I've tried very hard to find "all [the] existing users of kernhist(9)"
    but it is possible that I've missed some of them.  I would be glad to
    update any stragglers that anyone identifies.

Restore all work from the former pgoyette-localcount branch (which is
now abandoned doe to cvs merge botch).

The branch now builds, and installs via anita.  There are still some
problems (cgd is non-functional and all atf tests time-out) but they
will get resolved soon.

Sync with HEAD

Sync with HEAD.  (Note that most of these changes are simply $NetBSD$
tag issues.)

Omit needless nullmmap.

Convert the one user of it to nommap.  No functional change to the
device driver, since uvm interpreted nullmmap just like nommap.

This slightly changes the uvm ABI so that the function pointer nullop
is no longer interpreted as non-mmappable.  I do hereby declare that
I am surfing the kernel version bump from a few hours ago.

Adapt machine-independant code to the new {b,c}devsw reference-counting
(using localcount(9)).  All callers of {b,c}devsw_lookup() now call
{b,c}devsw_lookup_acquire() which retains a reference on the 'struct
{b,c}devsw'.  This reference must be released by the caller once it is
finished with the structure's content (or other data that would disappear
if the 'struct {b,c}devsw' were to disappear).

Sync with HEAD

Pull up following revision(s) (requested by chs in ticket #363):
	common/lib/libprop/prop_kern.c: revision 1.18
	sys/arch/mac68k/dev/grf_compat.c: revision 1.27
	sys/arch/x68k/dev/grf.c: revision 1.45
	sys/external/bsd/drm/dist/bsd-core/drm_bufs.c: revision 1.12
	sys/external/bsd/drm2/drm/drm_drv.c: revision 1.12
	sys/external/bsd/drm2/drm/drm_vm.c: revision 1.6
	sys/external/bsd/drm2/include/linux/mm.h: revision 1.4
	sys/kern/vfs_vnops.c: revision 1.192 via patch
	sys/rump/librump/rumpkern/vm.c: revision 1.160
	sys/sys/file.h: revision 1.78 via patch
	sys/uvm/uvm_device.c: revision 1.64
	sys/uvm/uvm_device.h: revision 1.13
	sys/uvm/uvm_extern.h: revision 1.192
	sys/uvm/uvm_mmap.c: revision 1.150 via patch
add a new "fo_mmap" fileops method to allow use of arbitrary uvm_objects for
mappings of file objects.  move vnode-specific details of mmap()ing a vnode
from uvm_mmap() to the new vnode-specific vn_mmap().  add new uvm_mmap_dev()
and uvm_mmap_anon() convenience functions for mapping character devices
and anonymous memory, and replace all other calls to uvm_mmap() with those.
use the new fileop in drm2 so that libdrm can use mmap() to map things
like on other platforms (instead of the ioctl that we have used so far).

add a new "fo_mmap" fileops method to allow use of arbitrary uvm_objects for
mappings of file objects.  move vnode-specific details of mmap()ing a vnode
from uvm_mmap() to the new vnode-specific vn_mmap().  add new uvm_mmap_dev()
and uvm_mmap_anon() convenience functions for mapping character devices
and anonymous memory, and replace all other calls to uvm_mmap() with those.
use the new fileop in drm2 so that libdrm can use mmap() to map things
like on other platforms (instead of the ioctl that we have used so far).

sync with head

merge to -current.

extending vmem(9) to be able to allocated resources for it's own needs.
simplifying uvm_map handling (no special kernel entries anymore no relocking)
make malloc(9) a thin wrapper around kmem(9)
(with private interface for interrupt safety reasons)

releng@ acknowledged

Catchup with rmind-uvmplock merge.

Welcome to 5.99.53!  Merge rmind-uvmplock branch:

- Reorganize locking in UVM and provide extra serialisation for pmap(9).
  New lock order: [vmpage-owner-lock] -> pmap-lock.

- Simplify locking in some pmap(9) modules by removing P->V locking.

- Use lock object on vmobjlock (and thus vnode_t::v_interlock) to share
  the locks amongst UVM objects where necessary (tmpfs, layerfs, unionfs).

- Rewrite and optimise x86 TLB shootdown code, make it simpler and cleaner.
  Add TLBSTATS option for x86 to collect statistics about TLB shootdowns.

- Unify /dev/mem et al in MI code and provide required locking (removes
  kernel-lock on some ports).  Also, avoid cache-aliasing issues.

Thanks to Andrew Doran and Joerg Sonnenberger, as their initial patches
formed the core changes of this branch.

Sync with HEAD.

sync with head

Implement sharing of vnode_t::v_interlock amongst vnodes:
- Lock is shared amongst UVM objects using uvm_obj_setlock() or getnewvnode().
- Adjust vnode cache to handle unsharing, add VI_LOCKSHARE flag for that.
- Use sharing in tmpfs and layerfs for underlying object.
- Simplify locking in ubc_fault().
- Sprinkle some asserts.

Discussed with ad@.

Replace "malloc" in comments, remove unnecessary header inclusions.

sync with head

Sync with HEAD

need uvm_pmap.h for pmap_mmap_flags definition

add optional MD pmap_mmap_flags macro for passing flags between cdev_mmap
and pmap_enter, ok matt@

Sync with HEAD

udpate license clauses on my code to match the new-style BSD licenses.
based on diff that rmind@ sent me.

no functional change with this commit.

We already have a flag PMAP_NOCACHE.  s/PMAP_UNMANAGED/PMAN_NOCACHE/.
Pointed out by Chuck Silvers, thanks.

Comment.

Always map device pages via cdev as unmanaged for now.

I need this to read/write a NOR FlashROM from userland.  Otherwise pmaps
believe the physload'ed ROM region as managed, and map it as cache
enabled, which prevents me from reading ROM command status, etc.

sync to netbsd-5

Reorganise UVM locking to protect P->V state and serialise pmap(9)
operations on the same page(s) by always locking their owner.  Hence
lock order: "vmpage"-lock -> pmap-lock.

Patch, proposed on tech-kern@, from Andrew Doran.

Change struct uvm_object::vmobjlock to be dynamically allocated with
mutex_obj_alloc().  It allows us to share the locks among UVM objects.

sync with head

vnode.h is not used here.

Sync with HEAD.

sync with head.

Pull up following revision(s) (requested by mrg in ticket #826):
	sys/sys/conf.h: revision 1.135
	sys/uvm/uvm_device.c: revision 1.56
add a workaround for drm:
for device mmap()'s, if the D_NEGOFFSAFE flag is set, do not check
if the offset is negative.
this should go away with the test itself when all drivers are audited
and checked to not fail with negative offsets.

add a workaround for drm:

for device mmap()'s, if the D_NEGOFFSAFE flag is set, do not check
if the offset is negative.

this should go away with the test itself when all drivers are audited
and checked to not fail with negative offsets.

sync with head.

Sync with HEAD.

Sync with HEAD.

kill MALLOC and FREE macros.

Sync w/ -current. 34 merge conflicts to follow.

sync with head.

Sync with HEAD.

Also fix build.

udv_fault: pmap_update before releasing locks.

Sync with HEAD.

sync with head

sync with HEAD

Sync with HEAD

Merge vmlocking2 to head.

Sync with HEAD.

Sync with HEAD.

Pullup to HEAD

Sync with HEAD.

Sync with head.

Merge from vmlocking2 (use cdev_mmap()).

Fix merge error.

sync with head

Pull the vmlocking changes into a new branch.

Sync with HEAD.

constify pagerops.

sync with head.

destroy vmobjlock.

Sync with HEAD.

Sync with head.

handle UVM_UNKNOWN_OFFSET.

Pull in the initial set of changes for the vmlocking branch.

- sync with head.
- move sched_changepri back to kern_synch.c as it doesn't know PPQ anymore.

sync with head.

TRUE -> true, FALSE -> false

sync with head.

sync with head.

sync with head

use c99 initializers

sync with head.

Sync with head.

sync with head.

kill the "fault_type" argument to pager's pgo_fault() methods
it is never used
(and using it would comprise an abstraction violation imho)

merge ktrace-lwp.

Sync with HEAD. Here we go again...

Small whitespace tweak.

Use ANSI function decls.

introduce a macro to initialize uvm_object and use it.

Fix the sync with head I botched.

Sync with HEAD.

Sync with HEAD

Nuke __P().

sync kqueue with -current; this includes merge of gehenna-devsw branch,
merge of i386 MP branch, and part of autoconf rototil work

Catch up to -current.

Merge the gehenna-devsw branch into the trunk.

This merge changes the device switch tables from static array to
dynamically generated by config(8).

- All device switches is defined as a constant structure in device drivers.

- The new grammer ``device-major'' is introduced to ``files''.

	device-major <prefix> char <num> [block <num>] [<rules>]

- All device major numbers must be listed up in port dependent majors.<arch>
  by using this grammer.

- Added the new naming convention.
  The name of the device switch must be <prefix>_[bc]devsw for auto-generation
  of device switch tables.

- The backward compatibility of loading block/character device
  switch by LKM framework is broken. This is necessary to convert
  from block/character device major to device name in runtime and vice versa.

- The restriction to assign device major by LKM is completely removed.
  We don't need to reserve LKM entries for dynamic loading of device switch.

- In compile time, device major numbers list is packed into the kernel and
  the LKM framework will refer it to assign device major number dynamically.

Replace the direct-access to devsw table with calling devsw APIs.

Catch up to -current.
(CVS: It's not just a program. It's an adventure!)

Catch up with -current.

use the <sys/conf.h> macro to get the mmap footprint.

Sync kqueue branch with -current.

Catch up to -current.

Sync the thorpej-mips-cache branch with -current.

add RCSIDs, and in some cases, slightly cleanup #include order

Catch up with -current.

Catch up to -current.

a whole bunch of changes to improve performance and robustness under load:

 - remove special treatment of pager_map mappings in pmaps.  this is
   required now, since I've removed the globals that expose the address range.
   pager_map now uses pmap_kenter_pa() instead of pmap_enter(), so there's
   no longer any need to special-case it.
 - eliminate struct uvm_vnode by moving its fields into struct vnode.
 - rewrite the pageout path.  the pager is now responsible for handling the
   high-level requests instead of only getting control after a bunch of work
   has already been done on its behalf.  this will allow us to UBCify LFS,
   which needs tighter control over its pages than other filesystems do.
   writing a page to disk no longer requires making it read-only, which
   allows us to write wired pages without causing all kinds of havoc.
 - use a new PG_PAGEOUT flag to indicate that a page should be freed
   on behalf of the pagedaemon when it's unlocked.  this flag is very similar
   to PG_RELEASED, but unlike PG_RELEASED, PG_PAGEOUT can be cleared if the
   pageout fails due to eg. an indirect-block buffer being locked.
   this allows us to remove the "version" field from struct vm_page,
   and together with shrinking "loan_count" from 32 bits to 16,
   struct vm_page is now 4 bytes smaller.
 - no longer use PG_RELEASED for swap-backed pages.  if the page is busy
   because it's being paged out, we can't release the swap slot to be
   reallocated until that write is complete, but unlike with vnodes we
   don't keep a count of in-progress writes so there's no good way to
   know when the write is done.  instead, when we need to free a busy
   swap-backed page, just sleep until we can get it busy ourselves.
 - implement a fast-path for extending writes which allows us to avoid
   zeroing new pages.  this substantially reduces cpu usage.
 - encapsulate the data used by the genfs code in a struct genfs_node,
   which must be the first element of the filesystem-specific vnode data
   for filesystems which use genfs_{get,put}pages().
 - eliminate many of the UVM pagerops, since they aren't needed anymore
   now that the pager "put" operation is a higher-level operation.
 - enhance the genfs code to allow NFS to use the genfs_{get,put}pages
   instead of a modified copy.
 - clean up struct vnode by removing all the fields that used to be used by
   the vfs_cluster.c code (which we don't use anymore with UBC).
 - remove kmem_object and mb_object since they were useless.
   instead of allocating pages to these objects, we now just allocate
   pages with no object.  such pages are mapped in the kernel until they
   are freed, so we can use the mapping to find the page to free it.
   this allows us to remove splvm() protection in several places.

The sum of all these changes improves write throughput on my
decstation 5000/200 to within 1% of the rate of NetBSD 1.5
and reduces the elapsed time for "make release" of a NetBSD 1.5
source tree on my 128MB pc to 10% less than a 1.5 kernel took.

Update the kqueue branch to HEAD.

Update pmap_update to now take the updated pmap as an argument.
This will allow improvements to the pmaps so that they can more easily defer expensive operations, eg tlb/cache flush, til the last possible moment.

Currently this is a no-op on most platforms, so they should see no difference.

Reviewed by Jason.

Commit my "devvp" changes to the thorpej-devvp branch.  This
replaces the use of dev_t in most places with a struct vnode *.

This will form the basic infrastructure for real cloning device
support (besides being architecurally cleaner -- it'll be good
to get away from using numbers to represent objects).

Catch up to -current.

replace vm_page_t with struct vm_page *.

replace {simple_,}lock{_data,}_t with struct {simple,}lock {,*}.

remove trailing whitespace.

Sprinkle pmap_update() calls after calls to:
- pmap_enter()
- pmap_remove()
- pmap_protect()
- pmap_kenter_pa()
- pmap_kremove()
as described in pmap(9).

These calls are relatively conservative.  It may be possible to
optimize these a little more.

Catch up with -current.

Sync with HEAD.

eliminate the KERN_* error codes in favor of the traditional E* codes.
the mapping is:

KERN_SUCCESS			0
KERN_INVALID_ADDRESS		EFAULT
KERN_PROTECTION_FAILURE		EACCES
KERN_NO_SPACE			ENOMEM
KERN_INVALID_ARGUMENT		EINVAL
KERN_FAILURE			various, mostly turn into KASSERTs
KERN_RESOURCE_SHORTAGE		ENOMEM
KERN_NOT_RECEIVER		<unused>
KERN_NO_ACCESS			<unused>
KERN_PAGES_LOCKED		<unused>

Sync with HEAD.

eliminate the VM_PAGER_* error codes in favor of the traditional E* codes.
the mapping is:

VM_PAGER_OK		        0
VM_PAGER_BAD		        <unused>
VM_PAGER_FAIL		        <unused>
VM_PAGER_PEND		        0 (see below)
VM_PAGER_ERROR		        EIO
VM_PAGER_AGAIN		        EAGAIN
VM_PAGER_UNLOCK		        EBUSY
VM_PAGER_REFAULT	        ERESTART

for async i/o requests, it used to be possible for the request to
be convert to sync, and the pager would return VM_PAGER_OK or VM_PAGER_PEND
to indicate whether the caller should perform post-i/o cleanup.
this is no longer allowed; pagers must now return 0 to indicate that
the async i/o was successfully started, and the caller never needs to
worry about doing the post-i/o cleanup.

Sync with HEAD.

lots of cleanup:
use queue.h macros and KASSERT().
address amap offsets in pages instead of bytes.
make amap_ref() and amap_unref() take an amap, offset and length
  instead of a vm_map_entry_t.
improve whitespace and comments.

g/c unused pager ops "asyncget" and "aiodone".

Update thorpej_scsipi to -current as of a month ago

Pull up mmap paddr_t/off_t changes from trunk.

remove include of <vm/vm.h>

In udv_fault(), use an off_t for curr_offset so that the offset passed
to d_mmap isn't truncated on 64 bit architectures.

remove/move more mach vm header files:

	<vm/pglist.h> -> <uvm/uvm_pglist.h>
	<vm/vm_inherit.h> -> <uvm/uvm_inherit.h>
	<vm/vm_kern.h> -> into <uvm/uvm_extern.h>
	<vm/vm_object.h> -> nothing
	<vm/vm_pager.h> -> into <uvm/uvm_pager.h>

also includes a bunch of <vm/vm_page.h> include removals (due to redudancy
with <vm/vm.h>), and a scattering of other similar headers.

Change the kernel mmap interface so that the offset to map is an
"off_t" and the return value is a "paddr_t" to allow mappings
at offsets past 2^31 bytes.  Somewhat inspired by FreeBSD, which
only changed the offset to a "vm_offset_t".

Includes updates for the i386, pc532 and sh3 mmmmap from Jason Thorpe.

Pull up rev. 1.24:
uvm_detach: eliminate degenerate loop construction.

Pull up rev. 1.23:
Insert two missing `simple_unlock()'s' in udv_detach().

uvm_detach: eliminate degenerate loop construction.

Insert two missing `simple_unlock()'s' in udv_detach().

Sync w/ netbsd-1-5-base.

Don't silently truncate the voff_t offset to vaddr_t when passing it to
udv_attach. Pass the whole voff_t instead and do an explicite overflow
check before it is passed to the device's mmap handler (as "int", sadly).

remove the "shareprot" pagerop.  it's not needed anymore since
share maps are long gone.

Merge parts of chs-ubc2 into the trunk:
Add a new type voff_t (defined as a synonym for off_t) to describe offsets
into uvm objects, and update the appropriate interfaces to use it, the
most visible effect being the ability to mmap() file offsets beyond
the range of a vaddr_t.

Originally by Chuck Silvers; blame me for problems caused by merging this
into non-UBC.

Kill duplicate udv_attach() prototype; it's a public interface, and declared
in uvm_device.h.

Pull up to last week's -current.

Sync with -current

Change the pmap_enter() API slightly; pmap_enter() now returns an error
value (KERN_SUCCESS or KERN_RESOURCE_SHORTAGE) indicating if it succeeded
or failed.  Change the `wired' and `access_type' arguments to a single
`flags' argument, which includes the access type, and flags:

	PMAP_WIRED	the old `wired' boolean
	PMAP_CANFAIL	pmap_enter() is allowed to fail

If PMAP_CANFAIL is not specified, the pmap should behave as it always
has in the face of a drastic resource shortage: fall over dead.

Change the fault handler to deal with failure (which indicates resource
shortage) by unlocking everything, waiting for the pagedaemon to free
more memory, then retrying the fault.

Pull up revision 1.17 (requested by ross):
  Bugfix for device mmap fault handler, fixes serious performance
  problem with alpha X server.

Patch from chuq for uvm r/w map oscillation bug.
Fixes the XalphaNetBSD slowdown.

create a new type "voff_t" for uvm_object offsets
and define it to be "off_t".  also, remove pgo_asyncget().

Sync w/ -current.

sanity: use ';' to separate statements

Add a new `access type' argument to pmap_enter().  This indicates what type of
memory access a mapping was caused by.  This is passed through from uvm_fault()
and udv_fault(), and in most other cases is 0.
The pmap module may use this to preset R/M information.  On MMUs which require
R/M emulation, the implementation may preset the bits and avoid taking another
fault.  On MMUs which keep R/M information in hardware, the implementation may
preset its cached bits to speed up the next call to pmap_is_modified() or
pmap_is_referenced().

remove now >1 year old pre-release message.

modify udv_attach() and its caller (uvm_mmap()) so that it's passed the
offset and size of the requested region to be mapped, so that the
udv_attach() can use the device d_mmap() entry to check mappability
of the requested region.

after discussion with chuck, nuke pgo_attach from uvm_pagerops

check the return value of d_mmap before pmap_phys_address() gets hold of it.

remove unused share map code from UVM:
 - udv_fault() no longer has to worry about share map address translations
	on device faults.  simplify code.

Merge paddr_t changes into the main branch.

Revert cdevsw mmap routines to return int.

Split vm_offset_t and vm_size_t into paddr_t, psize_t, vaddr_t, and vsize_t.

Remove inclusions of syscall (and syscall argument) related header files;
we don't need them here.

KNF.

Merge with Lite2 + local changes

- add defopt's for UVM, UVMHIST and PMAP_NEW.
- remove unnecessary UVMHIST_DECL's.

restore rcsids

rearrange a bit for clarity.

RCS ID police.

initial import of the new virtual memory system, UVM, into -current.

UVM was written by chuck cranor <chuck@maria.wustl.edu>, with some
minor portions derived from the old Mach code.  i provided some help
getting swap and paging working, and other bug fixes/ideas.  chuck
silvers <chuq@chuq.com> also provided some other fixes.

this is the UVM kernel code portion.


this will be KNF'd shortly.  :-)

Initial revision