Commit Graph

62 Commits

Author SHA1 Message Date
Alan Cox
2d612d2dd2 When tmpfs and POSIX shm pagein a page for the sole purpose of performing
truncation, immediately queue the page for asynchronous laundering rather
than making the page pass through inactive queue first.

Reviewed by:	kib, markj
2016-12-11 19:24:41 +00:00
Alan Cox
7667839a7e Remove most of the code for implementing PG_CACHED pages. (This change does
not remove user-space visible fields from vm_cnt or all of the references to
cached pages from comments.  Those changes will come later.)

Reviewed by:	kib, markj
Tested by:	pho
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D8497
2016-11-15 18:22:50 +00:00
Alan Cox
ce3ee09b53 Eliminate unneeded vm_page_xbusy() and vm_page_xunbusy() operations when
neither vm_pager_has_page() nor vm_pager_get_pages() is called.

Reviewed by:	kib, markj
MFC after:	3 weeks
2016-08-14 22:00:45 +00:00
Jilles Tjoelker
6ea906eec0 posixshm: Fix lock leak when mac_posixshm_check_read rejects read.
While reading the code, I noticed that shm_read() returns without unlocking
foffset and rangelock if mac_posixshm_check_read() rejects the read.

Reviewed by:	kib, jhb, rwatson
Approved by:	re (gjb)
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D6927
2016-06-23 20:59:13 +00:00
Pedro F. Giffuni
55e0987aea sys: extend use of the howmany() macro when available.
We have a howmany() macro in the <sys/param.h> header that is
convenient to re-use as it makes things easier to read.
2016-04-26 15:38:17 +00:00
Jamie Gritton
44c16975a2 Clean up some style(9) violations. 2016-04-14 17:07:26 +00:00
Jamie Gritton
cc7b259a26 Separate POSIX sem/shm objects in jails, by prepending the jail's path
name to the object's "path".  While the objects don't have real path
names, it's a filesystem-like namespace, which allows jails to be
kept to their own space, but still allows the system / jail parent to
access a jail's IPC.

PR:		208082
2016-04-13 20:14:13 +00:00
Konstantin Belousov
1bdbd70599 Implement process-shared locks support for libthr.so.3, without
breaking the ABI.  Special value is stored in the lock pointer to
indicate shared lock, and offline page in the shared memory is
allocated to store the actual lock.

Reviewed by:	vangyzen (previous version)
Discussed with:	deischen, emaste, jhb, rwatson,
	Martin Simmons <martin@lispworks.com>
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
2016-02-28 17:52:33 +00:00
Gleb Smirnoff
b0cd20172d A change to KPI of vm_pager_get_pages() and underlying VOP_GETPAGES().
o With new KPI consumers can request contiguous ranges of pages, and
  unlike before, all pages will be kept busied on return, like it was
  done before with the 'reqpage' only. Now the reqpage goes away. With
  new interface it is easier to implement code protected from race
  conditions.

  Such arrayed requests for now should be preceeded by a call to
  vm_pager_haspage() to make sure that request is possible. This
  could be improved later, making vm_pager_haspage() obsolete.

  Strenghtening the promises on the business of the array of pages
  allows us to remove such hacks as swp_pager_free_nrpage() and
  vm_pager_free_nonreq().

o New KPI accepts two integer pointers that may optionally point at
  values for read ahead and read behind, that a pager may do, if it
  can. These pages are completely owned by pager, and not controlled
  by the caller.

  This shifts the UFS-specific readahead logic from vm_fault.c, which
  should be file system agnostic, into vnode_pager.c. It also removes
  one VOP_BMAP() request per hard fault.

Discussed with:	kib, alc, jeff, scottl
Sponsored by:	Nginx, Inc.
Sponsored by:	Netflix
2015-12-16 21:30:45 +00:00
Ed Schouten
7ee1b208c3 Add kern_shm_open().
This allows you to specify the capabilities that the new file descriptor
should have. This allows us to create shared memory objects that only
have the rights we're interested in.

The idea behind restricting the rights is that it makes it a lot easier
for CloudABI to get consistent behaviour across different operating
systems. We only need to make sure that a shared memory implementation
consistently implements the operations that are whitelisted.

Approved by:	kib
Obtained from:	https://github.com/NuxiNL/freebsd
2015-08-01 07:21:14 +00:00
Gleb Smirnoff
093c7f396d Make KPI of vm_pager_get_pages() more strict: if a pager changes a page
in the requested array, then it is responsible for disposition of previous
page and is responsible for updating the entry in the requested array.
Now consumers of KPI do not need to re-lookup the pages after call to
vm_pager_get_pages().

Reviewed by:	kib
Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.
2015-06-12 11:32:20 +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
Konstantin Belousov
b9062c934a Use correct length for sparse uiomove(). It must be the clipped to
the page size, len is the total transfer length, which may be larger
than zero_region.

Reported and tested by:	clusteradm (gjb)
Sponsored by:	The FreeBSD Foundation
X-MFC-With:	r281442
2015-04-24 22:05:12 +00:00
Will Andrews
6311d7aaf0 uiomove_object_page(): Avoid instantiating pages in sparse regions on reads.
Check whether the page being requested is either resident or on swap.  If
not, read from the zero_region instead of instantiating an unnecessary page.

This avoids consuming memory for sparse files on tmpfs, when they are read
by applications that do not use SEEK_HOLE/SEEK_DATA (which is most of them).

Reviewed by:	kib
MFC after:	1 week
Sponsored by:	Spectra Logic
2015-04-11 18:51:41 +00:00
Mateusz Guzik
90f54cbfeb fd: remove filedesc argument from fdclose
Just accept a thread instead. This makes it consistent with fdalloc.

No functional changes.
2015-04-11 15:40:28 +00:00
Alan Cox
f4c6aea395 Preset the object's color, or alignment, to maximize superpage usage.
MFC after:	5 days
2015-02-08 21:00:51 +00:00
John Baldwin
9696feebe2 Add a new fo_fill_kinfo fileops method to add type-specific information to
struct kinfo_file.
- Move the various fill_*_info() methods out of kern_descrip.c and into the
  various file type implementations.
- Rework the support for kinfo_ofile to generate a suitable kinfo_file object
  for each file and then convert that to a kinfo_ofile structure rather than
  keeping a second, different set of code that directly manipulates
  type-specific file information.
- Remove the shm_path() and ksem_info() layering violations.

Differential Revision:	https://reviews.freebsd.org/D775
Reviewed by:	kib, glebius (earlier version)
2014-09-22 16:20:47 +00:00
John Baldwin
2d69d0dcc2 Fix various issues with invalid file operations:
- Add invfo_rdwr() (for read and write), invfo_ioctl(), invfo_poll(),
  and invfo_kqfilter() for use by file types that do not support the
  respective operations.  Home-grown versions of invfo_poll() were
  universally broken (they returned an errno value, invfo_poll()
  uses poll_no_poll() to return an appropriate event mask).  Home-grown
  ioctl routines also tended to return an incorrect errno (invfo_ioctl
  returns ENOTTY).
- Use the invfo_*() functions instead of local versions for
  unsupported file operations.
- Reorder fileops members to match the order in the structure definition
  to make it easier to spot missing members.
- Add several missing methods to linuxfileops used by the OFED shim
  layer: fo_write(), fo_truncate(), fo_kqfilter(), and fo_stat().  Most
  of these used invfo_*(), but a dummy fo_stat() implementation was
  added.
2014-09-12 21:29:10 +00:00
Andreas Tobler
5be725d7e8 Rename shm_dict_init to shm_init to fix a compiler warning.
Reviewed by:	jhb
2014-08-29 21:50:32 +00:00
John Baldwin
610a2b3c45 Use a unit number allocator to provide suitable st_dev and st_ino values
for POSIX shared memory descriptors.  The implementation is similar to
that used for pipes.

MFC after:	1 week
2014-08-29 18:18:29 +00:00
Konstantin Belousov
70978c93b8 If vm_page_grab() allocates a new page, the page is not inserted into
page queue even when the allocation is not wired.  It is
responsibility of the vm_page_grab() caller to ensure that the page
does not end on the vm_object queue but not on the pagedaemon queue,
which would effectively create unpageable unwired page.

In exec_map_first_page() and vm_imgact_hold_page(), activate the page
immediately after unbusying it, to avoid leak.

In the uiomove_object_page(), deactivate page before the object is
unlocked.  There is no leak, since the page is deactivated after
uiomove_fromphys() finished.  But allowing non-queued non-wired page
in the unlocked object queue makes it impossible to assert that leak
does not happen in other places.

Reviewed by:	alc
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2014-08-13 05:44:08 +00:00
Rui Paulo
551a78956c In the shm_open() and shm_unlink() syscalls, export the path to KTR.
MFC after:	1 week
2014-08-01 23:29:04 +00:00
Konstantin Belousov
5d9b4508fd For md(4), posix shm(3) and tmpfs(5), free swap space used by paged in
dirty page, which is written by the process.

Reviewed by:	alc
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2014-07-28 14:27:05 +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-Mark Gurney
6f2b769cac change td_retval into a union w/ off_t, with defines to mask the
change...  This eliminates a cast, and also forces td_retval
(often 2 32-bit registers) to be aligned so that off_t's can be
stored there on arches with strict alignment requirements like
armeb (AVILA)...  On i386, this doesn't change alignment, and on
amd64 it doesn't either, as register_t is already 64bits...

This will also prevent future breakage due to people adding additional
fields to the struct...

This gets AVILA booting a bit farther...

Reviewed by:	bde
2014-03-16 00:53:40 +00:00
Robert Millan
f55a7d3058 Accept O_CLOEXEC in shm_open().
Reviewed by:	jilles, jhb
MFC after:	1 week
2014-01-24 21:05:07 +00:00
Konstantin Belousov
227aaa86ed Implement sendfile(2) for the posix shared memory segment file descriptor,
in addition to the regular files.

Requested by:	alc
Discussed with:	emaste
Tested by:	pho (previous version)
Sponsored by:	The FreeBSD Foundation
Approved by:	re (hrs)
2013-09-11 06:41:15 +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
Konstantin Belousov
5944de8ecd Remove the deprecated VM_ALLOC_RETRY flag for the vm_page_grab(9).
The flag was mandatory since r209792, where vm_page_grab(9) was
changed to only support the alloc retry semantic.

Suggested and reviewed by:	alc
Sponsored by:	The FreeBSD Foundation
2013-08-22 07:39:53 +00:00
Konstantin Belousov
940cb0e2bb Implement read(2)/write(2) and neccessary lseek(2) for posix shmfd.
Add MAC framework entries for posix shm read and write.

Do not allow implicit extension of the underlying memory segment past
the limit set by ftruncate(2) by either of the syscalls.  Read and
write returns short i/o, lseek(2) fails with EINVAL when resulting
offset does not fit into the limit.

Discussed with:	alc
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
2013-08-21 17:45:00 +00:00
Konstantin Belousov
41cf41fdfd Extract the general-purpose code from tmpfs to perform uiomove from
the page queue of some vm object.

Discussed with:	alc
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
2013-08-21 17:23:24 +00:00
Gleb Smirnoff
ca04d21d5f Make sendfile() a method in the struct fileops. Currently only
vnode backed file descriptors have this method implemented.

Reviewed by:	kib
Sponsored by:	Nginx, Inc.
Sponsored by:	Netflix
2013-08-15 07:54:31 +00:00
Attilio Rao
c7aebda8a1 The soft and hard busy mechanism rely on the vm object lock to work.
Unify the 2 concept into a real, minimal, sxlock where the shared
acquisition represent the soft busy and the exclusive acquisition
represent the hard busy.
The old VPO_WANTED mechanism becames the hard-path for this new lock
and it becomes per-page rather than per-object.
The vm_object lock becames an interlock for this functionality:
it can be held in both read or write mode.
However, if the vm_object lock is held in read mode while acquiring
or releasing the busy state, the thread owner cannot make any
assumption on the busy state unless it is also busying it.

Also:
- Add a new flag to directly shared busy pages while vm_page_alloc
  and vm_page_grab are being executed.  This will be very helpful
  once these functions happen under a read object lock.
- Move the swapping sleep into its own per-object flag

The KPI is heavilly changed this is why the version is bumped.
It is very likely that some VM ports users will need to change
their own code.

Sponsored by:	EMC / Isilon storage division
Discussed with:	alc
Reviewed by:	jeff, kib
Tested by:	gavin, bapt (older version)
Tested by:	pho, scottl
2013-08-09 11:11:11 +00:00
John Baldwin
5e3a17c0b9 Use VMFS_OPTIMAL_SPACE instead of VMFS_ALIGNED_SPACE in shm_map(). 2013-07-24 20:34:25 +00:00
Jilles Tjoelker
b68cf25fe6 mqueue,ksem,shm: Fix race condition with setting UF_EXCLOSE.
POSIX mqueue, compatibility ksem and POSIX shm create a file descriptor that
has close-on-exec set. However, they do this incorrectly, leaving a window
where a thread may fork and exec while the flag has not been set yet. The
race is easily reproduced on a multicore system with one thread doing
shm_open and close and another thread doing posix_spawnp and waitpid.

Set UF_EXCLOSE via falloc()'s flags argument instead. This also simplifies
the code.

MFC after:	1 week
2013-04-07 15:26:09 +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
John Baldwin
e506e182dd Export some more useful info about shared memory objects to userland
via procstat(1) and fstat(1):
- Change shm file descriptors to track the pathname they are associated
  with and add a shm_path() method to copy the path out to a caller-supplied
  buffer.
- Use the fo_stat() method of shared memory objects and shm_path() to
  export the path, mode, and size of a shared memory object via
  struct kinfo_file.
- Add a struct shmstat to the libprocstat(3) interface along with a
  procstat_get_shm_info() to export the mode and size of a shared memory
  object.
- Change procstat to always print out the path for a given object if it
  is valid.
- Teach fstat about shared memory objects and to display their path,
  mode, and size.

MFC after:	2 weeks
2012-04-01 18:22:48 +00:00
Alan Cox
2971897d51 Correct an error of omission in the implementation of the truncation
operation on POSIX shared memory objects and tmpfs.  Previously, neither of
these modules correctly handled the case in which the new size of the object
or file was not a multiple of the page size.  Specifically, they did not
handle partial page truncation of data stored on swap.  As a result, stale
data might later be returned to an application.

Interestingly, a data inconsistency was less likely to occur under tmpfs
than POSIX shared memory objects.  The reason being that a different mistake
by the tmpfs truncation operation helped avoid a data inconsistency.  If the
data was still resident in memory in a PG_CACHED page, then the tmpfs
truncation operation would reactivate that page, zero the truncated portion,
and leave the page pinned in memory.  More precisely, the benevolent error
was that the truncation operation didn't add the reactivated page to any of
the paging queues, effectively pinning the page.  This page would remain
pinned until the file was destroyed or the page was read or written.  With
this change, the page is now added to the inactive queue.

Discussed with:	jhb
Reviewed by:	kib (an earlier version)
MFC after:	3 weeks
2012-01-08 20:09:26 +00:00
John Baldwin
338e7cf235 Use vm_mmap_to_errno().
Submitted by:	kib
2011-12-15 15:17:19 +00:00
John Baldwin
fb680e16f4 Add a helper API to allow in-kernel code to map portions of shared memory
objects created by shm_open(2) into the kernel's address space.  This
provides a convenient way for creating shared memory buffers between
userland and the kernel without requiring custom character devices.
2011-12-14 22:22:19 +00:00
Konstantin Belousov
dc874f9881 Rename vm_page_set_valid() to vm_page_set_valid_range().
The vm_page_set_valid() is the most reasonable name for the m->valid
accessor.

Reviewed by:	attilio, alc
2011-11-30 17:39:00 +00:00
Kip Macy
8451d0dd78 In order to maximize the re-usability of kernel code in user space this
patch modifies makesyscalls.sh to prefix all of the non-compatibility
calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel
entry points and all places in the code that use them. It also
fixes an additional name space collision between the kernel function
psignal and the libc function of the same name by renaming the kernel
psignal kern_psignal(). By introducing this change now we will ease future
MFCs that change syscalls.

Reviewed by:	rwatson
Approved by:	re (bz)
2011-09-16 13:58:51 +00:00
Robert Watson
9b6dd12e5d Correct several issues in the integration of POSIX shared memory objects
and the new setmode and setowner fileops in FreeBSD 9.0:

- Add new MAC Framework entry point mac_posixshm_check_create() to allow
  MAC policies to authorise shared memory use.  Provide a stub policy and
  test policy templates.

- Add missing Biba and MLS implementations of mac_posixshm_check_setmode()
  and mac_posixshm_check_setowner().

- Add 'accmode' argument to mac_posixshm_check_open() -- unlike the
  mac_posixsem_check_open() entry point it was modeled on, the access mode
  is required as shared memory access can be read-only as well as writable;
  this isn't true of POSIX semaphores.

- Implement full range of POSIX shared memory entry points for Biba and MLS.

Sponsored by:   Google Inc.
Obtained from:	TrustedBSD Project
Approved by:    re (kib)
2011-09-02 17:40:39 +00:00
Konstantin Belousov
68889ed699 Fix build breakage. Initialize error variables explicitely for !MAC case.
Pointy hat to:	kib
Approved by:	re (bz)
2011-08-17 12:37:14 +00:00
Konstantin Belousov
9c00bb9190 Add the fo_chown and fo_chmod methods to struct fileops and use them
to implement fchown(2) and fchmod(2) support for several file types
that previously lacked it. Add MAC entries for chown/chmod done on
posix shared memory and (old) in-kernel posix semaphores.

Based on the submission by:	glebius
Reviewed by:	rwatson
Approved by:	re (bz)
2011-08-16 20:07:47 +00:00
Jonathan Anderson
12bc222e57 Add some checks to ensure that Capsicum is behaving correctly, and add some
more explicit comments about what's going on and what future maintainers
need to do when e.g. adding a new operation to a sys_machdep.c.

Approved by: mentor(rwatson), re(bz)
2011-06-30 10:56:02 +00:00
Alan Cox
6bbee8e28a Add a new option, OBJPR_NOTMAPPED, to vm_object_page_remove(). Passing this
option to vm_object_page_remove() asserts that the specified range of pages
is not mapped, or more precisely that none of these pages have any managed
mappings.  Thus, vm_object_page_remove() need not call pmap_remove_all() on
the pages.

This change not only saves time by eliminating pointless calls to
pmap_remove_all(), but it also eliminates an inconsistency in the use of
pmap_remove_all() versus related functions, like pmap_remove_write().  It
eliminates harmless but pointless calls to pmap_remove_all() that were being
performed on PG_UNMANAGED pages.

Update all of the existing assertions on pmap_remove_all() to reflect this
change.

Reviewed by:	kib
2011-06-29 16:40:41 +00:00
Konstantin Belousov
1fe80828e7 After the r219999 is merged to stable/8, rename fallocf(9) to falloc(9)
and remove the falloc() version that lacks flag argument. This is done
to reduce the KPI bloat.

Requested by:	jhb
X-MFC-note:	do not
2011-04-01 13:28:34 +00:00
Edward Tomasz Napierala
ef694c1ac4 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
2010-12-02 17:37:16 +00:00