MFC

Add new pager type, OBJT_MGTDEVICE. It provides the device pager
which carries fictitous managed pages. In particular, the consumers of
the new object type can remove all mappings of the device page

Add new pager type, OBJT_MGTDEVICE. It provides the device pager
which carries fictitous managed pages. In particular, the consumers of
the new object type can remove all mappings of the device page with
pmap_remove_all().

The range of physical addresses used for fake page allocation shall be
registered with vm_phys_fictitious_reg_range() interface to allow the
PHYS_TO_VM_PAGE() to work in pmap.

Most likely, only i386 and amd64 pmaps can handle fictitious managed
pages right now.

Sponsored by: The FreeBSD Foundation
Reviewed by: alc
MFC after: 1 month

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svn+ssh://svn.freebsd.org/base/head@216199

Sync: merge r215944 through r216132 from ^/head.

Replace pointer to "struct uidinfo" with pointer to "struct ucred"
in "struct vm_object". This is required to make it possible to account
for per-jail swap usage.

Reviewed by: kib@
Tested by: pho@

Replace pointer to "struct uidinfo" with pointer to "struct ucred"
in "struct vm_object". This is required to make it possible to account
for per-jail swap usage.

Reviewed by: kib@
Tested by: pho@
Sponsored by: FreeBSD Foundation

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IFH@204581

Merge from head at r201628.

# This hasn't been tested, and there are at least three bad commits
# that need to be backed out before the branch will be stable again.

Replace VM_PROT_OVERRIDE_WRITE by VM_PROT_COPY. VM_PROT_OVERRIDE_WRITE has
represented a write access that is allowed to override write protection.
Until now, VM_PROT_OVERRIDE_WRITE has been used to

Replace VM_PROT_OVERRIDE_WRITE by VM_PROT_COPY. VM_PROT_OVERRIDE_WRITE has
represented a write access that is allowed to override write protection.
Until now, VM_PROT_OVERRIDE_WRITE has been used to write breakpoints into
text pages. Text pages are not just write protected but they are also
copy-on-write. VM_PROT_OVERRIDE_WRITE overrides the write protection on the
text page and triggers the replication of the page so that the breakpoint
will be written to a private copy. However, here is where things become
confused. It is the debugger, not the process being debugged that requires
write access to the copied page. Nonetheless, the copied page is being
mapped into the process with write access enabled. In other words, once the
debugger sets a breakpoint within a text page, the program can write to its
private copy of that text page. Whereas prior to setting the breakpoint, a
SIGSEGV would have occurred upon a write access. VM_PROT_COPY addresses
this problem. The combination of VM_PROT_READ and VM_PROT_COPY forces the
replication of a copy-on-write page even though the access is only for read.
Moreover, the replicated page is only mapped into the process with read
access, and not write access.

Reviewed by: kib
MFC after: 4 weeks

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MFC 196615:
Extend the device pager to support different memory attributes on different
pages in an object.
- Add a new variant of d_mmap() currently called d_mmap2() which accepts
an additional in

MFC 196615:
Extend the device pager to support different memory attributes on different
pages in an object.
- Add a new variant of d_mmap() currently called d_mmap2() which accepts
an additional in/out parameter that is the memory attribute to use for
the requested page.
- A driver either uses d_mmap() or d_mmap2() for all requests but not both.
The current implementation uses a flag in the cdevsw (D_MMAP2) to indicate
that the driver provides a d_mmap2() handler instead of d_mmap(). This
is done to make the change ABI compatible with existing drivers and
MFC'able to 7 and 8.

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Merge from head

- MFC from head@196987

Extend the device pager to support different memory attributes on different
pages in an object.
- Add a new variant of d_mmap() currently called d_mmap2() which accepts
an additional in/out paramet

Extend the device pager to support different memory attributes on different
pages in an object.
- Add a new variant of d_mmap() currently called d_mmap2() which accepts
an additional in/out parameter that is the memory attribute to use for
the requested page.
- A driver either uses d_mmap() or d_mmap2() for all requests but not both.
The current implementation uses a flag in the cdevsw (D_MMAP2) to indicate
that the driver provides a d_mmap2() handler instead of d_mmap(). This
is done to make the change ABI compatible with existing drivers and
MFC'able to 7 and 8.

Submitted by: alc
MFC after: 1 month

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- MFC @196061

Add a new type of VM object: OBJT_SG. An OBJT_SG object is very similar to
a device pager (OBJT_DEVICE) object in that it uses fictitious pages to
provide aliases to other memory addresses. The pri

Add a new type of VM object: OBJT_SG. An OBJT_SG object is very similar to
a device pager (OBJT_DEVICE) object in that it uses fictitious pages to
provide aliases to other memory addresses. The primary difference is that
it uses an sglist(9) to determine the physical addresses for a given offset
into the object instead of invoking the d_mmap() method in a device driver.

Reviewed by: alc
Approved by: re (kensmith)
MFC after: 2 weeks

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Add support to the virtual memory system for configuring machine-
dependent memory attributes:

Rename vm_cache_mode_t to vm_memattr_t. The new name reflects the
fact that there are machine-dependen

Add support to the virtual memory system for configuring machine-
dependent memory attributes:

Rename vm_cache_mode_t to vm_memattr_t. The new name reflects the
fact that there are machine-dependent memory attributes that have
nothing to do with controlling the cache's behavior.

Introduce vm_object_set_memattr() for setting the default memory
attributes that will be given to an object's pages.

Introduce and use pmap_page_{get,set}_memattr() for getting and
setting a page's machine-dependent memory attributes. Add full
support for these functions on amd64 and i386 and stubs for them on
the other architectures. The function pmap_page_set_memattr() is also
responsible for any other machine-dependent aspects of changing a
page's memory attributes, such as flushing the cache or updating the
direct map. The uses include kmem_alloc_contig(), vm_page_alloc(),
and the device pager:

kmem_alloc_contig() can now be used to allocate kernel memory with
non-default memory attributes on amd64 and i386.

vm_page_alloc() and the device pager will set the memory attributes
for the real or fictitious page according to the object's default
memory attributes.

Update the various pmap functions on amd64 and i386 that map pages to
incorporate each page's memory attributes in the mapping.

Notes: (1) Inherent to this design are safety features that prevent
the specification of inconsistent memory attributes by different
mappings on amd64 and i386. In addition, the device pager provides a
warning when a device driver creates a fictitious page with memory
attributes that are inconsistent with the real page that the
fictitious page is an alias for. (2) Storing the machine-dependent
memory attributes for amd64 and i386 as a dedicated "int" in "struct
md_page" represents a compromise between space efficiency and the ease
of MFCing these changes to RELENG_7.

In collaboration with: jhb

Approved by: re (kib)

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- MFC

This change is the next step in implementing the cache control functionality
required by video card drivers. Specifically, this change introduces
vm_cache_mode_t with an appropriate VM_CACHE_DEFAULT

This change is the next step in implementing the cache control functionality
required by video card drivers. Specifically, this change introduces
vm_cache_mode_t with an appropriate VM_CACHE_DEFAULT definition on all
architectures. In addition, this changes adds a vm_cache_mode_t parameter
to kmem_alloc_contig() and vm_phys_alloc_contig(). These will be the
interfaces for allocating mapped kernel memory and physical memory,
respectively, with non-default cache modes.

In collaboration with: jhb

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Implement global and per-uid accounting of the anonymous memory. Add
rlimit RLIMIT_SWAP that limits the amount of swap that may be reserved
for the uid.

The accounting information (charge) is associ

Implement global and per-uid accounting of the anonymous memory. Add
rlimit RLIMIT_SWAP that limits the amount of swap that may be reserved
for the uid.

The accounting information (charge) is associated with either map entry,
or vm object backing the entry, assuming the object is the first one
in the shadow chain and entry does not require COW. Charge is moved
from entry to object on allocation of the object, e.g. during the mmap,
assuming the object is allocated, or on the first page fault on the
entry. It moves back to the entry on forks due to COW setup.

The per-entry granularity of accounting makes the charge process fair
for processes that change uid during lifetime, and decrements charge
for proper uid when region is unmapped.

The interface of vm_pager_allocate(9) is extended by adding struct ucred *,
that is used to charge appropriate uid when allocation if performed by
kernel, e.g. md(4).

Several syscalls, among them is fork(2), may now return ENOMEM when
global or per-uid limits are enforced.

In collaboration with: pho
Reviewed by: alc
Approved by: re (kensmith)

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Add the superpage reservation type.

Retire debug.mpsafevm. None of the architectures supported in CVS require
it any longer.

- Change the vm_mmap() function to accept an objtype_t parameter specifying
the type of object represented by the handle argument.
- Allow vm_mmap() to map device memory via cdev objects in additio

- Change the vm_mmap() function to accept an objtype_t parameter specifying
the type of object represented by the handle argument.
- Allow vm_mmap() to map device memory via cdev objects in addition to
vnodes and anonymous memory. Note that mmaping a cdev directly does not
currently perform any MAC checks like mapping a vnode does.
- Unbreak the DRM getbufs ioctl by having it call vm_mmap() directly on the
cdev the ioctl is acting on rather than trying to find a suitable vnode
to map from.

Reviewed by: alc, arch@

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/* -> /*- for license, minor formatting changes

- Introduce and use a new tunable "debug.mpsafevm". At present, setting
"debug.mpsafevm" results in (almost) Giant-free execution of zero-fill
page faults. (Giant is held only briefly, just l

- Introduce and use a new tunable "debug.mpsafevm". At present, setting
"debug.mpsafevm" results in (almost) Giant-free execution of zero-fill
page faults. (Giant is held only briefly, just long enough to determine
if there is a vnode backing the faulting address.)

Also, condition the acquisition and release of Giant around calls to
pmap_remove() on "debug.mpsafevm".

The effect on performance is significant. On my dual Opteron, I see a
3.6% reduction in "buildworld" time.

- Use atomic operations to update several counters in vm_fault().

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Remove advertising clause from University of California Regent's license,
per letter dated July 22, 1999.

Approved by: core

Change the way ELF coredumps are handled. Instead of unconditionally
skipping read-only pages, which can result in valuable non-text-related
data not getting dumped, the ELF loader and the dynamic l

Change the way ELF coredumps are handled. Instead of unconditionally
skipping read-only pages, which can result in valuable non-text-related
data not getting dumped, the ELF loader and the dynamic loader now mark
read-only text pages NOCORE and the coredump code only checks (primarily) for
complete inaccessibility of the page or NOCORE being set.

Certain applications which map large amounts of read-only data will
produce much larger cores. A new sysctl has been added,
debug.elf_legacy_coredump, which will revert to the old behavior.

This commit represents collaborative work by all parties involved.
The PR contains a program demonstrating the problem.

PR: kern/45994
Submitted by: "Peter Edwards" <pmedwards@eircom.net>, Archie Cobbs <archie@dellroad.org>
Reviewed by: jdp, dillon
MFC after: 7 days

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