vm_object: do not assume that un_pager.devp.dev is cdev

It is subtype-specific handle. Mark OBJT_DEVICE that do fill cdev into
the handle, with a new object flag OBJ_CDEVH.

PR: 282533
Reviewed by:

vm_object: do not assume that un_pager.devp.dev is cdev

It is subtype-specific handle. Mark OBJT_DEVICE that do fill cdev into
the handle, with a new object flag OBJ_CDEVH.

PR: 282533
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D47443

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Remove never implemented sbrk and sstk syscalls

Both system calls were stubs returning EOPNOTSUPP and libc did not
provide _ or __sys_ prefixed symbols. The actual implementation of
sbrk(2) is on t

Remove never implemented sbrk and sstk syscalls

Both system calls were stubs returning EOPNOTSUPP and libc did not
provide _ or __sys_ prefixed symbols. The actual implementation of
sbrk(2) is on top of the undocumented break(2) system call.

Technically this is a change in ABI, but no non-contrived program ever
called these syscalls.

Reviewed by: kib, emaste
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D42872

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sys: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl s

sys: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

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sys: Remove $FreeBSD$: one-line .c pattern

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

vm: Allow MAP_32BIT for all architectures

Reviewed by: alc, kib, markj
Differential revision: https://reviews.freebsd.org/D41435

vm: MAP_32BIT_MAX_ADDR defined in sys/mman.h

Reviewed by: kib
Differential revision: https://reviews.freebsd.org/D41434

vm: Fix address hints of 0 with MAP_32BIT

Also, rename min_addr to default_addr, which better reflects what it
represents. The min_addr is not a minimum address in the same way that
max_addr is act

vm: Fix address hints of 0 with MAP_32BIT

Also, rename min_addr to default_addr, which better reflects what it
represents. The min_addr is not a minimum address in the same way that
max_addr is actually a maximum address that can be allocated. For
example, a non-zero hint can be less than min_addr and be allocated.

Reported by: dchagin
Reviewed by: dchagin, kib, markj
Fixes: d8e6f4946cec0 "vm: Fix anonymous memory clustering under ASLR"
Differential Revision: https://reviews.freebsd.org/D41397

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linuxolator: implement Linux' PROT_GROWSDOWN

From the Linux man page for mprotect(2):
PROT_GROWSDOWN
Apply the protection mode down to the beginning of a mapping
that grows down

linuxolator: implement Linux' PROT_GROWSDOWN

From the Linux man page for mprotect(2):
PROT_GROWSDOWN
Apply the protection mode down to the beginning of a mapping
that grows downward (which should be a stack segment or a
segment mapped with the MAP_GROWSDOWN flag set).

Reported by: dchagin
Reviewed by: alc, markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D41099

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vm_mmap_object: Update the spelling of true/false

Since fitit is already a bool, use true/false instead of TRUE/FALSE.

MFC after: 2 weeks

vm: Fix anonymous memory clustering under ASLR

By default, our ASLR implementation is supposed to cluster anonymous
memory allocations, unless the application's mmap(..., MAP_ANON, ...)
call include

vm: Fix anonymous memory clustering under ASLR

By default, our ASLR implementation is supposed to cluster anonymous
memory allocations, unless the application's mmap(..., MAP_ANON, ...)
call included a non-zero address hint. Unfortunately, clustering
never occurred because kern_mmap() always replaced the given address
hint when it was zero. So, the ASLR implementation always believed
that a non-zero hint had been provided and randomized the mapping's
location in the address space. To fix this problem, I'm pushing down
the point at which we convert a hint of zero to the minimum allocatable
address from kern_mmap() to vm_map_find_min().

Reviewed by: kib
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D40743

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vm: Remove handling for OBJT_DEFAULT objects

Now that OBJT_DEFAULT objects can't be instantiated, we can simplify
checks of the form object->type == OBJT_DEFAULT || (object->flags &
OBJ_SWAP) != 0.

vm: Remove handling for OBJT_DEFAULT objects

Now that OBJT_DEFAULT objects can't be instantiated, we can simplify
checks of the form object->type == OBJT_DEFAULT || (object->flags &
OBJ_SWAP) != 0. No functional change intended.

Reviewed by: alc, kib
Tested by: pho
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D35788

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vm_mmap: Remove obsolete code and comments from vm_mmap()

In preparation for removing OBJT_DEFAULT, eliminate some stale/unhelpful
comments from vm_mmap(), and remove an unused case. In particular,

vm_mmap: Remove obsolete code and comments from vm_mmap()

In preparation for removing OBJT_DEFAULT, eliminate some stale/unhelpful
comments from vm_mmap(), and remove an unused case. In particular, the
remaining callers of vm_mmap() in the tree do not specify OBJT_DEFAULT.

It's much more common to use vm_map_find() to map an object into user
memory, so rather than adjusting vm_mmap() to handle OBJT_SWAP objects,
let's further discourage its use and simply remove OBJT_DEFAULT
handling.

Reviewed by: dougm, alc, kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D35778

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vm: Fix racy checks for swap objects

Commit 4b8365d752ef introduced the ability to dynamically register
VM object types, for use by tmpfs, which creates swap-backed objects.
As a part of this, check

vm: Fix racy checks for swap objects

Commit 4b8365d752ef introduced the ability to dynamically register
VM object types, for use by tmpfs, which creates swap-backed objects.
As a part of this, checks for such objects changed from

object->type == OBJT_DEFAULT || object->type == OBJT_SWAP

to

object->type == OBJT_DEFAULT || (object->flags & OBJ_SWAP) != 0

In particular, objects of type OBJT_DEFAULT do not have OBJ_SWAP set;
the swap pager sets this flag when converting from OBJT_DEFAULT to
OBJT_SWAP.

A few of these checks are done without the object lock held. It turns
out that this can result in false negatives since the swap pager
converts objects like so:

object->type = OBJT_SWAP;
object->flags |= OBJ_SWAP;

Fix the problem by adding explicit tests for OBJT_SWAP objects in
unlocked checks.

PR: 258932
Fixes: 4b8365d752ef ("Add OBJT_SWAP_TMPFS pager")
Reported by: bdrewery
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D35470

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syscallarg_t: Add a type for system call arguments

This more clearly differentiates system call arguments from integer
registers and return values. On current architectures it has no effect,
but on

syscallarg_t: Add a type for system call arguments

This more clearly differentiates system call arguments from integer
registers and return values. On current architectures it has no effect,
but on architectures where pointers are not integers (CHERI) and may
not even share registers (CHERI-MIPS) it is necessiary to differentiate
between system call arguments (syscallarg_t) and integer register values
(register_t).

Obtained from: CheriBSD

Reviewed by: imp, kib
Differential Revision: https://reviews.freebsd.org/D33780

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Revert "syscallarg_t: Add a type for system call arguments"

Missed issues in truss on at least armv7 and powerpcspe need to be
resolved before recommit.

This reverts commit 3889fb8af0b611e3126dc250

Revert "syscallarg_t: Add a type for system call arguments"

Missed issues in truss on at least armv7 and powerpcspe need to be
resolved before recommit.

This reverts commit 3889fb8af0b611e3126dc250ebffb01805152104.
This reverts commit 1544e0f5d1f1e3b8c10a64cb899a936976ca7ea4.

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syscallarg_t: Add a type for system call arguments

This more clearly differentiates system call arguments from integer
registers and return values. On current architectures it has no effect,
but on

syscallarg_t: Add a type for system call arguments

This more clearly differentiates system call arguments from integer
registers and return values. On current architectures it has no effect,
but on architectures where pointers are not integers (CHERI) and may
not even share registers (CHERI-MIPS) it is necessiary to differentiate
between system call arguments (syscallarg_t) and integer register values
(register_t).

Obtained from: CheriBSD

Reviewed by: imp, kib
Differential Revision: https://reviews.freebsd.org/D33780

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ommap: fix signed len and pos arguments

4.3 BSD's mmap took an int len and long pos. Reject negative lengths
and in freebsd32 sign-extend pos correctly rather than mis-handling
negative positions a

ommap: fix signed len and pos arguments

4.3 BSD's mmap took an int len and long pos. Reject negative lengths
and in freebsd32 sign-extend pos correctly rather than mis-handling
negative positions as large positive ones.

Reviewed by: kib

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Add OBJT_SWAP_TMPFS pager

This is OBJT_SWAP pager, specialized for tmpfs. Right now, both swap pager
and generic vm code have to explicitly handle swap objects which are tmpfs
vnode v_object, in th

Add OBJT_SWAP_TMPFS pager

This is OBJT_SWAP pager, specialized for tmpfs. Right now, both swap pager
and generic vm code have to explicitly handle swap objects which are tmpfs
vnode v_object, in the special ways. Replace (almost) all such places with
proper methods.

Since VM still needs a notion of the 'swap object', regardless of its
use, add yet another type-classification flag OBJ_SWAP. Set it in
vm_object_allocate() where other type-class flags are set.

This change almost completely eliminates the knowledge of tmpfs from VM,
and opens a way to make OBJT_SWAP_TMPFS loadable from tmpfs.ko.

Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D30070

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Rename kern_mmap_req to kern_mmap

Replace all uses of kern_mmap with kern_mmap_req move the old kern_mmap.
Reand rename kern_mmap_req to kern_mmap .

The helper saved

Rename kern_mmap_req to kern_mmap

Replace all uses of kern_mmap with kern_mmap_req move the old kern_mmap.
Reand rename kern_mmap_req to kern_mmap .

The helper saved some code churn initially, but having multiple
interfaces is sub-optimal.

Obtained from: CheriBSD
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D28292

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vm_map_protect: allow to set prot and max_prot in one go.

This prevents a situation where other thread modifies map entries
permissions between setting max_prot, then relocking, then setting prot,
c

vm_map_protect: allow to set prot and max_prot in one go.

This prevents a situation where other thread modifies map entries
permissions between setting max_prot, then relocking, then setting prot,
confusing the operation outcome. E.g. you can get an error that is not
possible if operation is performed atomic.

Also enable setting rwx for max_prot even if map does not allow to set
effective rwx protection.

Reviewed by: brooks, markj (previous version)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D28117

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Support for userspace non-transparent superpages (largepages).

Created with shm_open2(SHM_LARGEPAGE) and then configured with
FIOSSHMLPGCNF ioctl, largepages posix shared memory objects guarantee
th

Support for userspace non-transparent superpages (largepages).

Created with shm_open2(SHM_LARGEPAGE) and then configured with
FIOSSHMLPGCNF ioctl, largepages posix shared memory objects guarantee
that all userspace mappings of it are served by superpage non-managed
mappings.

Only amd64 for now, both 2M and 1G superpages can be requested, the
later requires CPU feature.

Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D24652

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Prepare to handle non-trivial errors from vm_map_delete().

Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org

Prepare to handle non-trivial errors from vm_map_delete().

Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D24652

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Add kern_mmap_racct_check(), a helper to verify limits in vm_mmap*().

Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.

Add kern_mmap_racct_check(), a helper to verify limits in vm_mmap*().

Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D24652

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Include the psind in data returned by mincore(2).

Currently we use a single bit to indicate whether the virtual page is
part of a superpage. To support a forthcoming implementation of
non-transpare

Include the psind in data returned by mincore(2).

Currently we use a single bit to indicate whether the virtual page is
part of a superpage. To support a forthcoming implementation of
non-transparent 1GB superpages, it is useful to provide more detailed
information about large page sizes.

The change converts MINCORE_SUPER into a mask for MINCORE_PSIND(psind)
values, indicating a mapping of size psind, where psind is an index into
the pagesizes array returned by getpagesizes(3), which in turn comes
from the hw.pagesizes sysctl. MINCORE_PSIND(1) is equal to the old
value of MINCORE_SUPER.

For now, two bits are used to record the page size, permitting values
of MAXPAGESIZES up to 4.

Reviewed by: alc, kib
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D26238

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vm: clean up empty lines in .c and .h files