Commit Graph

309 Commits

Author SHA1 Message Date
Mark Johnston
010ba3842c Add a local variable initialization needed in the OBJT_DEFAULT case.
Reviewed by:	kib
Differential Revision:	https://reviews.freebsd.org/D2992
2015-07-05 22:26:19 +00:00
Mateusz Guzik
cd336bad26 vm: don't lock proc around accesses to vm_{t,d}addr and RLIMIT_DATA in sys_mmap
vm_{t,d}addr are constant and we can use thread's copy of resource limits
2015-07-02 18:30:12 +00:00
Mateusz Guzik
f6f6d24062 Implement lockless resource limits.
Use the same scheme implemented to manage credentials.

Code needing to look at process's credentials (as opposed to thred's) is
provided with *_proc variants of relevant functions.

Places which possibly had to take the proc lock anyway still use the proc
pointer to access limits.
2015-06-10 10:48:12 +00:00
John Baldwin
7077c42623 Add a new file operations hook for mmap operations. File type-specific
logic is now placed in the mmap hook implementation rather than requiring
it to be placed in sys/vm/vm_mmap.c.  This hook allows new file types to
support mmap() as well as potentially allowing mmap() for existing file
types that do not currently support any mapping.

The vm_mmap() function is now split up into two functions.  A new
vm_mmap_object() function handles the "back half" of vm_mmap() and accepts
a referenced VM object to map rather than a (handle, handle_type) tuple.
vm_mmap() is now reduced to converting a (handle, handle_type) tuple to a
a VM object and then calling vm_mmap_object() to handle the actual mapping.
The vm_mmap() function remains for use by other parts of the kernel
(e.g. device drivers and exec) but now only supports mapping vnodes,
character devices, and anonymous memory.

The mmap() system call invokes vm_mmap_object() directly with a NULL object
for anonymous mappings.  For mappings using a file descriptor, the
descriptors fo_mmap() hook is invoked instead.  The fo_mmap() hook is
responsible for performing type-specific checks and adjustments to
arguments as well as possibly modifying mapping parameters such as flags
or the object offset.  The fo_mmap() hook routines then call
vm_mmap_object() to handle the actual mapping.

The fo_mmap() hook is optional.  If it is not set, then fo_mmap() will
fail with ENODEV.  A fo_mmap() hook is implemented for regular files,
character devices, and shared memory objects (created via shm_open()).

While here, consistently use the VM_PROT_* constants for the vm_prot_t
type for the 'prot' variable passed to vm_mmap() and vm_mmap_object()
as well as the vm_mmap_vnode() and vm_mmap_cdev() helper routines.
Previously some places were using the mmap()-specific PROT_* constants
instead.  While this happens to work because PROT_xx == VM_PROT_xx,
using VM_PROT_* is more correct.

Differential Revision:	https://reviews.freebsd.org/D2658
Reviewed by:	alc (glanced over), kib
MFC after:	1 month
Sponsored by:	Chelsio
2015-06-04 19:41:15 +00:00
Edward Tomasz Napierala
4b5c9cf62f Add kern.racct.enable tunable and RACCT_DISABLED config option.
The point of this is to be able to add RACCT (with RACCT_DISABLED)
to GENERIC, to avoid having to rebuild the kernel to use rctl(8).

Differential Revision:	https://reviews.freebsd.org/D2369
Reviewed by:	kib@
MFC after:	1 month
Relnotes:	yes
Sponsored by:	The FreeBSD Foundation
2015-04-29 10:23:02 +00:00
Konstantin Belousov
0538aafc41 The lseek(2), mmap(2), truncate(2), ftruncate(2), pread(2), and
pwrite(2) syscalls are wrapped to provide compatibility with pre-7.x
kernels which required padding before the off_t parameter.  The
fcntl(2) contains compatibility code to handle kernels before the
struct flock was changed during the 8.x CURRENT development.  The
shims were reasonable to allow easier revert to the older kernel at
that time.

Now, two or three major releases later, shims do not serve any
purpose.  Such old kernels cannot handle current libc, so revert the
compatibility code.

Make padded syscalls support conditional under the COMPAT6 config
option.  For COMPAT32, the syscalls were under COMPAT6 already.

Remove WITHOUT_SYSCALL_COMPAT build option, which only purpose was to
(partially) disable the removed shims.

Reviewed by:	jhb, imp (previous versions)
Discussed with:	peter
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-04-18 21:50:13 +00:00
Alan Cox
3d653db063 Introduce vm_object_color() and use it in mmap(2) to set the color of
named objects to zero before the virtual address is selected.  Previously,
the color setting was delayed until after the virtual address was
selected.  In rtld, this delay effectively prevented the mapping of a
shared library's code section using superpages.  Now, for example, we see
the first 1 MB of libc's code on armv6 mapped by a superpage after we've
gotten through the initial cold misses that bring the first 1 MB of code
into memory.  (With the page clustering that we perform on read faults,
this happens quickly.)

Differential Revision:	https://reviews.freebsd.org/D2013
Reviewed by:	jhb, kib
Tested by:	Svatopluk Kraus (armv6)
MFC after:	6 weeks
2015-03-21 17:56:55 +00:00
Alan Cox
f81b73f3aa Eliminate a variable that became unused when VFS_LOCK_GIANT() was
eliminated.

MFC after:	3 days
2015-02-28 19:11:37 +00:00
John Baldwin
01ca58b23c Always ignore the deprecated MAP_RENAME and MAP_NORESERVE flags to mmap().
Some old libraries may be used even with newer binaries (specifically the
Nvidia driver libraries).

Differential Revision:	https://reviews.freebsd.org/D1262
Reviewed by:	kib
2014-12-05 15:24:42 +00:00
John Baldwin
5817298f31 Retire the unimplemented MAP_RENAME and MAP_NORESERVE flags to mmap(2).
Older binaries are still permitted to use these flags.

PR:		193961 (exp-run in ports)
Differential Revision:	https://reviews.freebsd.org/D848
Reviewed by:	kib
2014-10-18 12:28:51 +00:00
Konstantin Belousov
10204535af The vm_mmap_cdev() explicitely converts absence of both MAP_SHARED and
MAP_PRIVATE flags to MAP_SHARED.  Apparently, some code in tree, in
particular, libgeom, relied on this behaviour, see r271721.  For
regular file types, the absence of the flags is interpreted as
MAP_PRIVATE, and libc nlist used this (fixed in r271723).

Allow the implicit flags for legacy binaries.  Bump __FreeBSD_version
to get the ABI note on new binaries to check for in mmap code.

Remove the test for presence of one of the MAP_ANON, MAP_SHARED or
MAP_PRIVATE flags before fget_mmap().  For MAP_ANON, we already verify
that passed fd == -1.  For fd != -1, test after fget_mmap() (for newer
binaries) covers the case.

Reported by:	bdrewery, pho
Reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
2014-09-17 21:04:50 +00:00
John Baldwin
8bafac5444 Permit MAP_RENAME and MAP_NORESERVE for now. These flags should be removed, but at least
Chromium and OpenJDK use MAP_NORESERVE.
2014-09-16 17:21:06 +00:00
John Baldwin
5fd3f8b3b6 Add stricter checking of some mmap() arguments:
- Fail with EINVAL if an invalid protection mask is passed to mmap().
- Fail with EINVAL if an unknown flag is passed to mmap().
- Fail with EINVAL if both MAP_PRIVATE and MAP_SHARED are passed to mmap().
- Require one of either MAP_PRIVATE or MAP_SHARED for non-anonymous
  mappings.

Reviewed by:	alc, kib
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D698
2014-09-15 17:20:13 +00:00
Marcel Moolenaar
e7d939bda2 Remove ia64.
This includes:
o   All directories named *ia64*
o   All files named *ia64*
o   All ia64-specific code guarded by __ia64__
o   All ia64-specific makefile logic
o   Mention of ia64 in comments and documentation

This excludes:
o   Everything under contrib/
o   Everything under crypto/
o   sys/xen/interface
o   sys/sys/elf_common.h

Discussed at: BSDcan
2014-07-07 00:27:09 +00:00
Hans Petter Selasky
af3b2549c4 Pull in r267961 and r267973 again. Fix for issues reported will follow. 2014-06-28 03:56:17 +00:00
Glen Barber
37a107a407 Revert r267961, r267973:
These changes prevent sysctl(8) from returning proper output,
such as:

 1) no output from sysctl(8)
 2) erroneously returning ENOMEM with tools like truss(1)
    or uname(1)
 truss: can not get etype: Cannot allocate memory
2014-06-27 22:05:21 +00:00
Hans Petter Selasky
3da1cf1e88 Extend the meaning of the CTLFLAG_TUN flag to automatically check if
there is an environment variable which shall initialize the SYSCTL
during early boot. This works for all SYSCTL types both statically and
dynamically created ones, except for the SYSCTL NODE type and SYSCTLs
which belong to VNETs. A new flag, CTLFLAG_NOFETCH, has been added to
be used in the case a tunable sysctl has a custom initialisation
function allowing the sysctl to still be marked as a tunable. The
kernel SYSCTL API is mostly the same, with a few exceptions for some
special operations like iterating childrens of a static/extern SYSCTL
node. This operation should probably be made into a factored out
common macro, hence some device drivers use this. The reason for
changing the SYSCTL API was the need for a SYSCTL parent OID pointer
and not only the SYSCTL parent OID list pointer in order to quickly
generate the sysctl path. The motivation behind this patch is to avoid
parameter loading cludges inside the OFED driver subsystem. Instead of
adding special code to the OFED driver subsystem to post-load tunables
into dynamically created sysctls, we generalize this in the kernel.

Other changes:
- Corrected a possibly incorrect sysctl name from "hw.cbb.intr_mask"
to "hw.pcic.intr_mask".
- Removed redundant TUNABLE statements throughout the kernel.
- Some minor code rewrites in connection to removing not needed
TUNABLE statements.
- Added a missing SYSCTL_DECL().
- Wrapped two very long lines.
- Avoid malloc()/free() inside sysctl string handling, in case it is
called to initialize a sysctl from a tunable, hence malloc()/free() is
not ready when sysctls from the sysctl dataset are registered.
- Bumped FreeBSD version to indicate SYSCTL API change.

MFC after:	2 weeks
Sponsored by:	Mellanox Technologies
2014-06-27 16:33:43 +00:00
Konstantin Belousov
11c42bcc54 Add MAP_EXCL flag for mmap(2). It should be combined with MAP_FIXED,
and prevents the request from deleting existing mappings in the
region, failing instead.

Reviewed by:	alc
Discussed with:	jhb
Tested by:	markj, pho (previous version, as part of the bigger patch)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2014-06-19 05:00:39 +00:00
Konstantin Belousov
4648ba0a0f Make mmap(MAP_STACK) search for the available address space, similar
to !MAP_STACK mapping requests.  For MAP_STACK | MAP_FIXED, clear any
mappings which could previously exist in the used range.

For this, teach vm_map_find() and vm_map_fixed() to handle
MAP_STACK_GROWS_DOWN or _UP cow flags, by calling a new
vm_map_stack_locked() helper, which is factored out from
vm_map_stack().

The side effect of the change is that MAP_STACK started obeying
MAP_ALIGNMENT and MAP_32BIT flags.

Reported by:	rwatson
Reviewed by:	alc
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2014-06-09 03:37:41 +00:00
Peter Holm
e103f5b1c0 msync(2) must return ENOMEM and not EINVAL when the address is outside the
allowed range or when one or more pages are not mapped. This according to
The Open Group Base Specifications Issue 7.

Discussed with:	 attilio, Bruce Evans
Reviewed by:	 alc, Garrett Cooper
Reported by:	 ATF
MFC after:	 2 weeks
Sponsored by:	EMC / Isilon storage division
2014-05-07 08:38:02 +00:00
Bryan Drewery
44f1c91610 Rename global cnt to vm_cnt to avoid shadowing.
To reduce the diff struct pcu.cnt field was not renamed, so
PCPU_OP(cnt.field) is still used. pc_cnt and pcpu are also used in
kvm(3) and vmstat(8). The goal was to not affect externally used KPI.

Bump __FreeBSD_version_ in case some out-of-tree module/code relies on the
the global cnt variable.

Exp-run revealed no ports using it directly.

No objection from:	arch@
Sponsored by:	EMC / Isilon Storage Division
2014-03-22 10:26:09 +00:00
Robert Watson
4a14441044 Update kernel inclusions of capability.h to use capsicum.h instead; some
further refinement is required as some device drivers intended to be
portable over FreeBSD versions rely on __FreeBSD_version to decide whether
to include capability.h.

MFC after:	3 weeks
2014-03-16 10:55:57 +00:00
John Baldwin
55648840de Extend the support for exempting processes from being killed when swap is
exhausted.
- Add a new protect(1) command that can be used to set or revoke protection
  from arbitrary processes.  Similar to ktrace it can apply a change to all
  existing descendants of a process as well as future descendants.
- Add a new procctl(2) system call that provides a generic interface for
  control operations on processes (as opposed to the debugger-specific
  operations provided by ptrace(2)).  procctl(2) uses a combination of
  idtype_t and an id to identify the set of processes on which to operate
  similar to wait6().
- Add a PROC_SPROTECT control operation to manage the protection status
  of a set of processes.  MADV_PROTECT still works for backwards
  compatability.
- Add a p_flag2 to struct proc (and a corresponding ki_flag2 to kinfo_proc)
  the first bit of which is used to track if P_PROTECT should be inherited
  by new child processes.

Reviewed by:	kib, jilles (earlier version)
Approved by:	re (delphij)
MFC after:	1 month
2013-09-19 18:53:42 +00:00
John Baldwin
6a87d217e2 Fix an off-by-one error when populating mincore(2) entries for
skipped entries.  lastvecindex references the last valid byte,
so the new bytes should come after it.

Approved by:	re (kib)
MFC after:	1 week
2013-09-12 20:46:32 +00:00
John Baldwin
edb572a38c Add a mmap flag (MAP_32BIT) on 64-bit platforms to request that a mapping use
an address in the first 2GB of the process's address space.  This flag should
have the same semantics as the same flag on Linux.

To facilitate this, add a new parameter to vm_map_find() that specifies an
optional maximum virtual address.  While here, fix several callers of
vm_map_find() to use a VMFS_* constant for the findspace argument instead of
TRUE and FALSE.

Reviewed by:	alc
Approved by:	re (kib)
2013-09-09 18:11:59 +00:00
Pawel Jakub Dawidek
7008be5bd7 Change the cap_rights_t type from uint64_t to a structure that we can extend
in the future in a backward compatible (API and ABI) way.

The cap_rights_t represents capability rights. We used to use one bit to
represent one right, but we are running out of spare bits. Currently the new
structure provides place for 114 rights (so 50 more than the previous
cap_rights_t), but it is possible to grow the structure to hold at least 285
rights, although we can make it even larger if 285 rights won't be enough.

The structure definition looks like this:

	struct cap_rights {
		uint64_t	cr_rights[CAP_RIGHTS_VERSION + 2];
	};

The initial CAP_RIGHTS_VERSION is 0.

The top two bits in the first element of the cr_rights[] array contain total
number of elements in the array - 2. This means if those two bits are equal to
0, we have 2 array elements.

The top two bits in all remaining array elements should be 0.
The next five bits in all array elements contain array index. Only one bit is
used and bit position in this five-bits range defines array index. This means
there can be at most five array elements in the future.

To define new right the CAPRIGHT() macro must be used. The macro takes two
arguments - an array index and a bit to set, eg.

	#define	CAP_PDKILL	CAPRIGHT(1, 0x0000000000000800ULL)

We still support aliases that combine few rights, but the rights have to belong
to the same array element, eg:

	#define	CAP_LOOKUP	CAPRIGHT(0, 0x0000000000000400ULL)
	#define	CAP_FCHMOD	CAPRIGHT(0, 0x0000000000002000ULL)

	#define	CAP_FCHMODAT	(CAP_FCHMOD | CAP_LOOKUP)

There is new API to manage the new cap_rights_t structure:

	cap_rights_t *cap_rights_init(cap_rights_t *rights, ...);
	void cap_rights_set(cap_rights_t *rights, ...);
	void cap_rights_clear(cap_rights_t *rights, ...);
	bool cap_rights_is_set(const cap_rights_t *rights, ...);

	bool cap_rights_is_valid(const cap_rights_t *rights);
	void cap_rights_merge(cap_rights_t *dst, const cap_rights_t *src);
	void cap_rights_remove(cap_rights_t *dst, const cap_rights_t *src);
	bool cap_rights_contains(const cap_rights_t *big, const cap_rights_t *little);

Capability rights to the cap_rights_init(), cap_rights_set(),
cap_rights_clear() and cap_rights_is_set() functions are provided by
separating them with commas, eg:

	cap_rights_t rights;

	cap_rights_init(&rights, CAP_READ, CAP_WRITE, CAP_FSTAT);

There is no need to terminate the list of rights, as those functions are
actually macros that take care of the termination, eg:

	#define	cap_rights_set(rights, ...)				\
		__cap_rights_set((rights), __VA_ARGS__, 0ULL)
	void __cap_rights_set(cap_rights_t *rights, ...);

Thanks to using one bit as an array index we can assert in those functions that
there are no two rights belonging to different array elements provided
together. For example this is illegal and will be detected, because CAP_LOOKUP
belongs to element 0 and CAP_PDKILL to element 1:

	cap_rights_init(&rights, CAP_LOOKUP | CAP_PDKILL);

Providing several rights that belongs to the same array's element this way is
correct, but is not advised. It should only be used for aliases definition.

This commit also breaks compatibility with some existing Capsicum system calls,
but I see no other way to do that. This should be fine as Capsicum is still
experimental and this change is not going to 9.x.

Sponsored by:	The FreeBSD Foundation
2013-09-05 00:09:56 +00:00
John Baldwin
5aa60b6f21 Add new mmap(2) flags to permit applications to request specific virtual
address alignment of mappings.
- MAP_ALIGNED(n) requests a mapping aligned on a boundary of (1 << n).
  Requests for n >= number of bits in a pointer or less than the size of
  a page fail with EINVAL.  This matches the API provided by NetBSD.
- MAP_ALIGNED_SUPER is a special case of MAP_ALIGNED.  It can be used
  to optimize the chances of using large pages.  By default it will align
  the mapping on a large page boundary (the system is free to choose any
  large page size to align to that seems best for the mapping request).
  However, if the object being mapped is already using large pages, then
  it will align the virtual mapping to match the existing large pages in
  the object instead.
- Internally, VMFS_ALIGNED_SPACE is now renamed to VMFS_SUPER_SPACE, and
  VMFS_ALIGNED_SPACE(n) is repurposed for specifying a specific alignment.
  MAP_ALIGNED(n) maps to using VMFS_ALIGNED_SPACE(n), while
  MAP_ALIGNED_SUPER maps to VMFS_SUPER_SPACE.
- mmap() of a device object now uses VMFS_OPTIMAL_SPACE rather than
  explicitly using VMFS_SUPER_SPACE.  All device objects are forced to
  use a specific color on creation, so VMFS_OPTIMAL_SPACE is effectively
  equivalent.

Reviewed by:	alc
MFC after:	1 month
2013-08-16 21:13:55 +00:00
Jeremie Le Hen
fc2b167929 Fix previous commit when option RACCT is not used.
MFC after:	7 days
2013-07-22 22:16:47 +00:00
Jeremie Le Hen
c92b506977 Fix a panic in the racct code when munlock(2) is called with incorrect values.
The racct code in sys_munlock() assumed that the boundaries provided by the
userland were correct as long as vm_map_unwire() returned successfully.
However the latter contains its own logic and sometimes manages to do something
out of those boundaries, even if they are buggy.  This change makes the racct
code to use the accounting done by the vm layer, as it is done in other places
such as vm_mlock().

Despite fixing the panic, Alan Cox pointed that this code is still race-y
though: two simultaneous callers will produce incorrect values.

Reviewed by:	alc
MFC after:	7 days
2013-07-22 21:47:14 +00:00
John Baldwin
ff74a3fa6b Be more aggressive in using superpages in all mappings of objects:
- Add a new address space allocation method (VMFS_OPTIMAL_SPACE) for
  vm_map_find() that will try to alter the alignment of a mapping to match
  any existing superpage mappings of the object being mapped.  If no
  suitable address range is found with the necessary alignment,
  vm_map_find() will fall back to using the simple first-fit strategy
  (VMFS_ANY_SPACE).
- Change mmap() without MAP_FIXED, shmat(), and the GEM mapping ioctl to
  use VMFS_OPTIMAL_SPACE instead of VMFS_ANY_SPACE.

Reviewed by:	alc (earlier version)
MFC after:	2 weeks
2013-07-19 19:06:15 +00:00
Gleb Smirnoff
995d706909 Make sys_mlock() function just a wrapper around vm_mlock() function
that does all the job.

Reviewed by:	kib, jilles
Sponsored by:	Nginx, Inc.
2013-06-08 13:13:40 +00:00
Konstantin Belousov
53f5f8a0e1 Add a hint suggesting why tmpfs does not need a special case there. 2013-05-02 18:35:12 +00:00
Konstantin Belousov
e5f299ff76 Make vm_object_page_clean() and vm_mmap_vnode() tolerate the vnode'
v_object of non OBJT_VNODE type.

For vm_object_page_clean(), simply do not assert that object type must
be OBJT_VNODE, and add a comment explaining how the check for
OBJ_MIGHTBEDIRTY prevents the rest of function from operating on such
objects.

For vm_mmap_vnode(), if the object type is not OBJT_VNODE, require it
to be for swap pager (or default), handle the bypass filesystems, and
correctly acquire the object reference in this case.

Reviewed by:	alc
Tested by:	pho, bf
MFC after:	1 week
2013-04-28 19:25:09 +00:00
Konstantin Belousov
bafa6cfc93 Release the v_writecount reference on the vnode in case of error,
before the vnode is vput() in vm_mmap_vnode().  Error return means
that there is no use reference on the vnode from the vm object
reference, and failing to restore v_writecount breaks the invariant
that v_writecount is less or equal to the usecount.

The situation observed when nfs client returns ESTALE for
VOP_GETATTR() after the open.

In collaboration with:	pho
MFC after:	1 week
2013-03-28 06:39:27 +00:00
Attilio Rao
89f6b8632c Switch the vm_object mutex to be a rwlock. This will enable in the
future further optimizations where the vm_object lock will be held
in read mode most of the time the page cache resident pool of pages
are accessed for reading purposes.

The change is mostly mechanical but few notes are reported:
* The KPI changes as follow:
  - VM_OBJECT_LOCK() -> VM_OBJECT_WLOCK()
  - VM_OBJECT_TRYLOCK() -> VM_OBJECT_TRYWLOCK()
  - VM_OBJECT_UNLOCK() -> VM_OBJECT_WUNLOCK()
  - VM_OBJECT_LOCK_ASSERT(MA_OWNED) -> VM_OBJECT_ASSERT_WLOCKED()
    (in order to avoid visibility of implementation details)
  - The read-mode operations are added:
    VM_OBJECT_RLOCK(), VM_OBJECT_TRYRLOCK(), VM_OBJECT_RUNLOCK(),
    VM_OBJECT_ASSERT_RLOCKED(), VM_OBJECT_ASSERT_LOCKED()
* The vm/vm_pager.h namespace pollution avoidance (forcing requiring
  sys/mutex.h in consumers directly to cater its inlining functions
  using VM_OBJECT_LOCK()) imposes that all the vm/vm_pager.h
  consumers now must include also sys/rwlock.h.
* zfs requires a quite convoluted fix to include FreeBSD rwlocks into
  the compat layer because the name clash between FreeBSD and solaris
  versions must be avoided.
  At this purpose zfs redefines the vm_object locking functions
  directly, isolating the FreeBSD components in specific compat stubs.

The KPI results heavilly broken by this commit.  Thirdy part ports must
be updated accordingly (I can think off-hand of VirtualBox, for example).

Sponsored by:	EMC / Isilon storage division
Reviewed by:	jeff
Reviewed by:	pjd (ZFS specific review)
Discussed with:	alc
Tested by:	pho
2013-03-09 02:32:23 +00:00
Pawel Jakub Dawidek
2609222ab4 Merge Capsicum overhaul:
- Capability is no longer separate descriptor type. Now every descriptor
  has set of its own capability rights.

- The cap_new(2) system call is left, but it is no longer documented and
  should not be used in new code.

- The new syscall cap_rights_limit(2) should be used instead of
  cap_new(2), which limits capability rights of the given descriptor
  without creating a new one.

- The cap_getrights(2) syscall is renamed to cap_rights_get(2).

- If CAP_IOCTL capability right is present we can further reduce allowed
  ioctls list with the new cap_ioctls_limit(2) syscall. List of allowed
  ioctls can be retrived with cap_ioctls_get(2) syscall.

- If CAP_FCNTL capability right is present we can further reduce fcntls
  that can be used with the new cap_fcntls_limit(2) syscall and retrive
  them with cap_fcntls_get(2).

- To support ioctl and fcntl white-listing the filedesc structure was
  heavly modified.

- The audit subsystem, kdump and procstat tools were updated to
  recognize new syscalls.

- Capability rights were revised and eventhough I tried hard to provide
  backward API and ABI compatibility there are some incompatible changes
  that are described in detail below:

	CAP_CREATE old behaviour:
	- Allow for openat(2)+O_CREAT.
	- Allow for linkat(2).
	- Allow for symlinkat(2).
	CAP_CREATE new behaviour:
	- Allow for openat(2)+O_CREAT.

	Added CAP_LINKAT:
	- Allow for linkat(2). ABI: Reuses CAP_RMDIR bit.
	- Allow to be target for renameat(2).

	Added CAP_SYMLINKAT:
	- Allow for symlinkat(2).

	Removed CAP_DELETE. Old behaviour:
	- Allow for unlinkat(2) when removing non-directory object.
	- Allow to be source for renameat(2).

	Removed CAP_RMDIR. Old behaviour:
	- Allow for unlinkat(2) when removing directory.

	Added CAP_RENAMEAT:
	- Required for source directory for the renameat(2) syscall.

	Added CAP_UNLINKAT (effectively it replaces CAP_DELETE and CAP_RMDIR):
	- Allow for unlinkat(2) on any object.
	- Required if target of renameat(2) exists and will be removed by this
	  call.

	Removed CAP_MAPEXEC.

	CAP_MMAP old behaviour:
	- Allow for mmap(2) with any combination of PROT_NONE, PROT_READ and
	  PROT_WRITE.
	CAP_MMAP new behaviour:
	- Allow for mmap(2)+PROT_NONE.

	Added CAP_MMAP_R:
	- Allow for mmap(PROT_READ).
	Added CAP_MMAP_W:
	- Allow for mmap(PROT_WRITE).
	Added CAP_MMAP_X:
	- Allow for mmap(PROT_EXEC).
	Added CAP_MMAP_RW:
	- Allow for mmap(PROT_READ | PROT_WRITE).
	Added CAP_MMAP_RX:
	- Allow for mmap(PROT_READ | PROT_EXEC).
	Added CAP_MMAP_WX:
	- Allow for mmap(PROT_WRITE | PROT_EXEC).
	Added CAP_MMAP_RWX:
	- Allow for mmap(PROT_READ | PROT_WRITE | PROT_EXEC).

	Renamed CAP_MKDIR to CAP_MKDIRAT.
	Renamed CAP_MKFIFO to CAP_MKFIFOAT.
	Renamed CAP_MKNODE to CAP_MKNODEAT.

	CAP_READ old behaviour:
	- Allow pread(2).
	- Disallow read(2), readv(2) (if there is no CAP_SEEK).
	CAP_READ new behaviour:
	- Allow read(2), readv(2).
	- Disallow pread(2) (CAP_SEEK was also required).

	CAP_WRITE old behaviour:
	- Allow pwrite(2).
	- Disallow write(2), writev(2) (if there is no CAP_SEEK).
	CAP_WRITE new behaviour:
	- Allow write(2), writev(2).
	- Disallow pwrite(2) (CAP_SEEK was also required).

	Added convinient defines:

	#define	CAP_PREAD		(CAP_SEEK | CAP_READ)
	#define	CAP_PWRITE		(CAP_SEEK | CAP_WRITE)
	#define	CAP_MMAP_R		(CAP_MMAP | CAP_SEEK | CAP_READ)
	#define	CAP_MMAP_W		(CAP_MMAP | CAP_SEEK | CAP_WRITE)
	#define	CAP_MMAP_X		(CAP_MMAP | CAP_SEEK | 0x0000000000000008ULL)
	#define	CAP_MMAP_RW		(CAP_MMAP_R | CAP_MMAP_W)
	#define	CAP_MMAP_RX		(CAP_MMAP_R | CAP_MMAP_X)
	#define	CAP_MMAP_WX		(CAP_MMAP_W | CAP_MMAP_X)
	#define	CAP_MMAP_RWX		(CAP_MMAP_R | CAP_MMAP_W | CAP_MMAP_X)
	#define	CAP_RECV		CAP_READ
	#define	CAP_SEND		CAP_WRITE

	#define	CAP_SOCK_CLIENT \
		(CAP_CONNECT | CAP_GETPEERNAME | CAP_GETSOCKNAME | CAP_GETSOCKOPT | \
		 CAP_PEELOFF | CAP_RECV | CAP_SEND | CAP_SETSOCKOPT | CAP_SHUTDOWN)
	#define	CAP_SOCK_SERVER \
		(CAP_ACCEPT | CAP_BIND | CAP_GETPEERNAME | CAP_GETSOCKNAME | \
		 CAP_GETSOCKOPT | CAP_LISTEN | CAP_PEELOFF | CAP_RECV | CAP_SEND | \
		 CAP_SETSOCKOPT | CAP_SHUTDOWN)

	Added defines for backward API compatibility:

	#define	CAP_MAPEXEC		CAP_MMAP_X
	#define	CAP_DELETE		CAP_UNLINKAT
	#define	CAP_MKDIR		CAP_MKDIRAT
	#define	CAP_RMDIR		CAP_UNLINKAT
	#define	CAP_MKFIFO		CAP_MKFIFOAT
	#define	CAP_MKNOD		CAP_MKNODAT
	#define	CAP_SOCK_ALL		(CAP_SOCK_CLIENT | CAP_SOCK_SERVER)

Sponsored by:	The FreeBSD Foundation
Reviewed by:	Christoph Mallon <christoph.mallon@gmx.de>
Many aspects discussed with:	rwatson, benl, jonathan
ABI compatibility discussed with:	kib
2013-03-02 00:53:12 +00:00
Andrey Zonov
3ac7d29722 - Reduce kernel size by removing unnecessary pointer indirections.
GENERIC kernel size reduced in 16 bytes and RACCT kernel in 336 bytes.

Suggested by:	alc
Reviewed by:	alc
Approved by:	kib (mentor)
MFC after:	1 week
2013-01-10 12:43:58 +00:00
Andrey Zonov
7e19eda4aa - Fix locked memory accounting for maps with MAP_WIREFUTURE flag.
- Add sysctl vm.old_mlock which may turn such accounting off.

Reviewed by:	avg, trasz
Approved by:	kib (mentor)
MFC after:	1 week
2012-12-18 07:35:01 +00:00
Konstantin Belousov
5050aa86cf Remove the support for using non-mpsafe filesystem modules.
In particular, do not lock Giant conditionally when calling into the
filesystem module, remove the VFS_LOCK_GIANT() and related
macros. Stop handling buffers belonging to non-mpsafe filesystems.

The VFS_VERSION is bumped to indicate the interface change which does
not result in the interface signatures changes.

Conducted and reviewed by:	attilio
Tested by:	pho
2012-10-22 17:50:54 +00:00
Andrey Zonov
c4e357e8d3 - Simplify VM code by using vmspace_wired_count() for counting wired
memory of a process.

Reviewed by:	avg
Approved by:	kib (mentor)
MFC after:	2 weeks
2012-09-05 18:19:54 +00:00
Konstantin Belousov
ee4116b8f7 For old mmap syscall, when executing on amd64 or ia64, enforce the
PROT_EXEC if prot is non-zero, process is 32bit and
kern.elf32.i386_read_exec syscal is enabled. This workaround is needed
for old i386 a.out binaries, where dynamic linker did not specified
PROT_EXEC for mapping of the text.

The kern.elf32.i386_read_exec MIB name looks weird for a.out binaries,
but I reused the existing knob which already has the needed semantic.

MFC after:	1 week
2012-08-14 12:11:48 +00:00
Konstantin Belousov
7707ccabfb Adjust the r205536, by allowing a non-zero offset for anonymous
mappings for a.out binaries. Apparently, a.out ld.so from FreeBSD
1.1.5.1 can issue such requests.

Reported and tested by:	Dan Plassche <dplassche@gmail.com>
MFC after:	1 week
2012-08-14 11:47:07 +00:00
Konstantin Belousov
1472f4f4b9 When MAP_STACK mapping is created, the map entry is created only to
cover the initial stack size. For MCL_WIREFUTURE maps, the subsequent
call to vm_map_wire() to wire the whole stack region fails due to
VM_MAP_WIRE_NOHOLES flag.

Use the VM_MAP_WIRE_HOLESOK to only wire mapped part of the stack.

Reported and tested by:	Sushanth Rai <sushanth_rai yahoo com>
Reviewed by:	alc
MFC after:	1 week
2012-04-21 18:36:53 +00:00
Alan Cox
1c8279e4e7 Fix mincore(2) so that it reports PG_CACHED pages as resident.
MFC after:	2 weeks
2012-04-08 18:25:12 +00:00
Konstantin Belousov
126d60823a In vm_object_page_clean(), do not clean OBJ_MIGHTBEDIRTY object flag
if the filesystem performed short write and we are skipping the page
due to this.

Propogate write error from the pager back to the callers of
vm_pageout_flush().  Report the failure to write a page from the
requested range as the FALSE return value from vm_object_page_clean(),
and propagate it back to msync(2) to return EIO to usermode.

While there, convert the clearobjflags variable in the
vm_object_page_clean() and arguments of the helper functions to
boolean.

PR:	kern/165927
Reviewed by:	alc
MFC after:	2 weeks
2012-03-17 23:00:32 +00:00
Alan Cox
83cbe16ff4 Eliminate stale incorrect ARGSUSED comments.
Submitted by:	bde
2012-03-02 17:33:51 +00:00
Alan Cox
f9230ad6b8 Simplify vm_mmap()'s control flow.
Add a comment describing what vm_mmap_to_errno() does.

Reviewed by:	kib
MFC after:	3 weeks
X-MFC after:	r232071
2012-02-25 21:06:39 +00:00
Konstantin Belousov
9d22083da8 Place the if() at the right location, to activate the v_writecount
accounting for shared writeable mappings for all filesystems, not only
for the bypass layers.

Submitted by:	alc
Pointy hat to:	kib
MFC after:	20 days
2012-02-24 10:41:58 +00:00
Konstantin Belousov
84110e7e0b Account the writeable shared mappings backed by file in the vnode
v_writecount.  Keep the amount of the virtual address space used by
the mappings in the new vm_object un_pager.vnp.writemappings
counter. The vnode v_writecount is incremented when writemappings gets
non-zero value, and decremented when writemappings is returned to
zero.

Writeable shared vnode-backed mappings are accounted for in vm_mmap(),
and vm_map_insert() is instructed to set MAP_ENTRY_VN_WRITECNT flag on
the created map entry.  During deferred map entry deallocation,
vm_map_process_deferred() checks for MAP_ENTRY_VN_WRITECOUNT and
decrements writemappings for the vm object.

Now, the writeable mount cannot be demoted to read-only while
writeable shared mappings of the vnodes from the mount point
exist. Also, execve(2) fails for such files with ETXTBUSY, as it
should be.

Noted by:	tegge
Reviewed by:	tegge (long time ago, early version), alc
Tested by:	pho
MFC after:	3 weeks
2012-02-23 21:07:16 +00:00
Alan Cox
a649296959 When vm_mmap() is used to map a vm object into a kernel vm_map, it
makes no sense to check the size of the kernel vm_map against the
user-level resource limits for the calling process.

Reviewed by:	kib
2012-02-16 06:45:51 +00:00