Commit Graph

130 Commits

Author SHA1 Message Date
brooks
7698ed5201 Make vop_symlink take a const target path.
This will enable callers to take const paths as part of syscall
decleration improvements.

Where doing so is easy and non-distruptive carry the const through
implementations. In UFS the value is passed to an interface that must
take non-const values. In ZFS, const poisoning would touch code shared
with upstream and it's not worth adding diffs.

Bump __FreeBSD_version for external API consumers.

Reviewed by:	kib (prior version)
Obtained from:	CheriBSD
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D17805
2018-11-02 14:42:36 +00:00
jhb
0aaf564f94 Use long for the last argument to VOP_PATHCONF rather than a register_t.
pathconf(2) and fpathconf(2) both return a long.  The kern_[f]pathconf()
functions now accept a pointer to a long value rather than modifying
td_retval directly.  Instead, the system calls explicitly store the
returned long value in td_retval[0].

Requested by:	bde
Reviewed by:	kib
Sponsored by:	Chelsio Communications
2018-01-17 22:36:58 +00:00
glebius
8a7f8bb123 For UNIX sockets make vnode point not to the socket, but to the UNIX PCB,
since the latter is the thing that links together VFS and sockets.

While here, make the union in the struct vnode anonymous.
2017-06-02 17:31:25 +00:00
emaste
00b67b15b9 Renumber license clauses in sys/kern to avoid skipping #3 2016-09-15 13:16:20 +00:00
kib
40b1af3c86 Consistently delimit each vnode description block with two blank
lines.

Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
2016-08-27 18:12:42 +00:00
kib
aa6b4fc56a Add an implementation of fdatasync(2).
The syscall is a trivial wrapper around new VOP_FDATASYNC(), sharing
code with fsync(2).  For all filesystems, this commit provides the
implementation which delegates the work of VOP_FDATASYNC() to
VOP_FSYNC().  This is functionally correct but not efficient.

This is not yet POSIX-compliant implementation, because it does not
ensure that queued AIO requests are completed before returning.

Reviewed by:	mckusick
Discussed with:	avg (ZFS), jhb (AIO part)
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D7471
2016-08-15 19:08:51 +00:00
trasz
523c191717 Remove unused "X" vnode lock assertion, somehow missed in r303743.
MFC after:	1 month
2016-08-12 22:22:11 +00:00
trasz
522c3665ca Remove unused - never actually implemented - vnode lock types
from vnode_if.src.

MFC after:	1 month
2016-08-04 13:45:18 +00:00
kib
838f7d1304 Add EVFILT_VNODE open, read and close notifications.
While there, order EVFILT_VNODE notes descriptions alphabetically.

Based on submission, and tested by:	Vladimir Kondratyev <wulf@cicgroup.ru>
MFC after:	2 weeks
2016-05-03 15:17:43 +00:00
pfg
28823d0656 sys/kern: spelling fixes in comments.
No functional change.
2016-04-29 22:15:33 +00:00
glebius
63cd1c131a 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
cem
9fe341127e kevent(2): Note DOOMED vnodes with NOTE_REVOKE
In poll mode, check for and wake VBAD vnodes.  (Vnodes that are VBAD at
registration will never be woken by the RECLAIM trigger.)

Add post-VOP_RECLAIM hook to trigger notes on vnode reclamation.  (Vnodes that
were fine at registration but are vgoned while being monitored should signal
waiters.)

Reviewed by:	kib
Approved by:	markj (mentor)
Sponsored by:	EMC / Isilon Storage Division
Differential Revision:	https://reviews.freebsd.org/D3675
2015-09-15 20:22:30 +00:00
glebius
e4390a8823 Catch up on r271387 and remove unused parameter from
VOP_GETPAGES_ASYNC().
2015-03-30 22:49:26 +00:00
glebius
b4ef8e602d Merge from projects/sendfile:
o Provide a new VOP_GETPAGES_ASYNC(), which works like VOP_GETPAGES(), but
  doesn't sleep. It returns immediately, and will execute the I/O done handler
  function that must be supplied as argument.
o Provide VOP_GETPAGES_ASYNC() for the FFS, which uses vnode_pager.
o Extend pagertab to support pgo_getpages_async method, and implement this
  method for vnode_pager.

Reviewed by:	kib
Tested by:	pho
Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.
2014-11-23 12:01:52 +00:00
glebius
5939c729a8 Remove unused arguments for VOP_GETPAGES(), VOP_PUTPAGES(). 2014-09-10 12:36:41 +00:00
kib
9b734f0e00 If filesystem declares that it supports shared locking for writes, use
shared vnode lock for VOP_PUTPAGES() as well.  The only such
filesystem in the tree is ZFS, and it uses
vnode_pager_generic_putpages(), which performs the pageout with
VOP_WRITE().

Reviewed by:	alc
Discussed with:	avg
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2013-11-09 20:36:29 +00:00
avg
c20b4131f0 remove vop_lookup_pre and vop_lookup_post
Suggested by:	kib
MFC after:	5 days
2012-11-22 10:36:10 +00:00
avg
4d2c561ebf vnode_if: fix locking protocol description for lookup and cachedlookup
Also remove the checks from vop_lookup_pre and vop_lookup_post, which
are now completely redundant (before this change they were partially
redundant).

Discussed with:	kib
MFC after:	10 days
2012-11-19 11:32:56 +00:00
kib
f16ea99007 The r241025 fixed the case when a binary, executed from nullfs mount,
was still possible to open for write from the lower filesystem.  There
is a symmetric situation where the binary could already has file
descriptors opened for write, but it can be executed from the nullfs
overlay.

Handle the issue by passing one v_writecount reference to the lower
vnode if nullfs vnode has non-zero v_writecount.  Note that only one
write reference can be donated, since nullfs only keeps one use
reference on the lower vnode.  Always use the lower vnode v_writecount
for the checks.

Introduce the VOP_GET_WRITECOUNT to read v_writecount, which is
currently always bypassed to the lower vnode, and VOP_ADD_WRITECOUNT
to manipulate the v_writecount value, which manages a single bypass
reference to the lower vnode.  Caling the VOPs instead of directly
accessing v_writecount provide the fix described in the previous
paragraph.

Tested by:	pho
MFC after:	3 weeks
2012-11-02 13:56:36 +00:00
kib
8f845e475e Fix the mis-handling of the VV_TEXT on the nullfs vnodes.
If you have a binary on a filesystem which is also mounted over by
nullfs, you could execute the binary from the lower filesystem, or
from the nullfs mount. When executed from lower filesystem, the lower
vnode gets VV_TEXT flag set, and the file cannot be modified while the
binary is active. But, if executed as the nullfs alias, only the
nullfs vnode gets VV_TEXT set, and you still can open the lower vnode
for write.

Add a set of VOPs for the VV_TEXT query, set and clear operations,
which are correctly bypassed to lower vnode.

Tested by:	pho (previous version)
MFC after:	2 weeks
2012-09-28 11:25:02 +00:00
trociny
1aad0004ee Introduce VOP_UNP_BIND(), VOP_UNP_CONNECT(), and VOP_UNP_DETACH()
operations for setting and accessing vnode's v_socket field.

The operations are necessary to implement proper unix socket handling
on layered file systems like nullfs(5).

This change fixes the long standing issue with nullfs(5) being in that
unix sockets did not work between lower and upper layers: if we bound
to a socket on the lower layer we could connect only to the lower
path; if we bound to the upper layer we could connect only to the
upper path. The new behavior is one can connect to both the lower and
the upper paths regardless what layer path one binds to.

PR:		kern/51583, kern/159663
Suggested by:	kib
Reviewed by:	arch
MFC after:	2 weeks
2012-02-29 21:38:31 +00:00
jhb
519872f221 Add 5 spare VOPs as placeholders to avoid breaking the KBI in the future
when new VOPs are MFC'd to a branch.

Reviewed by:	kib, bz
MFC after:	3 days
2012-01-06 20:06:45 +00:00
jhb
33f06e36cf Add post-VOP hooks for VOP_DELETEEXTATTR() and VOP_SETEXTATTR() and use
these to trigger a NOTE_ATTRIB EVFILT_VNODE kevent when the extended
attributes of a vnode are changed.

Note that OS X already implements this behavior.

Reviewed by:	rwatson
MFC after:	2 weeks
2011-12-23 20:11:37 +00:00
jhb
78c075174e Add the posix_fadvise(2) system call. It is somewhat similar to
madvise(2) except that it operates on a file descriptor instead of a
memory region.  It is currently only supported on regular files.

Just as with madvise(2), the advice given to posix_fadvise(2) can be
divided into two types.  The first type provide hints about data access
patterns and are used in the file read and write routines to modify the
I/O flags passed down to VOP_READ() and VOP_WRITE().  These modes are
thus filesystem independent.  Note that to ease implementation (and
since this API is only advisory anyway), only a single non-normal
range is allowed per file descriptor.

The second type of hints are used to hint to the OS that data will or
will not be used.  These hints are implemented via a new VOP_ADVISE().
A default implementation is provided which does nothing for the WILLNEED
request and attempts to move any clean pages to the cache page queue for
the DONTNEED request.  This latter case required two other changes.
First, a new V_CLEANONLY flag was added to vinvalbuf().  This requests
vinvalbuf() to only flush clean buffers for the vnode from the buffer
cache and to not remove any backing pages from the vnode.  This is
used to ensure clean pages are not wired into the buffer cache before
attempting to move them to the cache page queue.  The second change adds
a new vm_object_page_cache() method.  This method is somewhat similar to
vm_object_page_remove() except that instead of freeing each page in the
specified range, it attempts to move clean pages to the cache queue if
possible.

To preserve the ABI of struct file, the f_cdevpriv pointer is now reused
in a union to point to the currently active advice region if one is
present for regular files.

Reviewed by:	jilles, kib, arch@
Approved by:	re (kib)
MFC after:	1 month
2011-11-04 04:02:50 +00:00
mdf
5ffb572962 Correctly use INOUT for the offset/len parameters to vop_allocate. As
far as I can tell this is for documentation only at the moment.
2011-05-13 14:29:28 +00:00
mdf
597ae9f19b Allow VOP_ALLOCATE to be iterative, and have kern_posix_fallocate(9)
drive looping and potentially yielding.

Requested by:	kib
2011-04-19 16:36:24 +00:00
mdf
9c9a32d97b Add the posix_fallocate(2) syscall. The default implementation in
vop_stdallocate() is filesystem agnostic and will run as slow as a
read/write loop in userspace; however, it serves to correctly
implement the functionality for filesystems that do not implement a
VOP_ALLOCATE.

Note that __FreeBSD_version was already bumped today to 900036 for any
ports which would like to use this function.

Also reserve space in the syscall table for posix_fadvise(2).

Reviewed by:	-arch (previous version)
2011-04-18 16:32:22 +00:00
zml
773cda6040 Add VOP_ADVLOCKPURGE so that the file system is called when purging
locks (in the case where the VFS impl isn't using lf_*)

Submitted by:       Matthew Fleming <matthew.fleming@isilon.com>
Reviewed by:        zml, dfr
2010-05-12 21:24:46 +00:00
kib
2fc79768f3 Add explicit struct ucred * argument for VOP_VPTOCNP, to be used by
vn_open_cred in default implementation. Valid struct ucred is needed for
audit and MAC, and curthread credentials may be wrong.

This further requires modifying the interface of vn_fullpath(9), but it
is out of scope of this change.

Reviewed by:	rwatson
2009-06-21 19:21:01 +00:00
ps
9cb3f3ca17 Stop asserting on exclusive locks in fsync since it can now support
shared vnode locking on ZFS.

Reviewed by:	jhb
2009-06-11 17:06:45 +00:00
ps
ae099c88f7 Simply shared vnode locking and extend it to also include fsync.
Also, in vop_write, no longer assert for exclusive locks on the
vnode.

Reviewed by:	jhb, kmacy, jeffr
2009-06-08 21:23:54 +00:00
trasz
0c63bcbfa4 Add VOP_ACCESSX, which can be used to query for newly added V*
permissions, such as VWRITE_ACL.  For a filsystems that don't
implement it, there is a default implementation, which works
as a wrapper around VOP_ACCESS.

Reviewed by:	rwatson@
2009-05-30 13:59:05 +00:00
rwatson
fba90f2e03 Remove VOP_LEASE and supporting functions. This hasn't been used since
the removal of NQNFS, but was left in in case it was required for NFSv4.
Since our new NFSv4 client and server can't use it for their
requirements, GC the old mechanism, as well as other unused lease-
related code and interfaces.

Due to its impact on kernel programming and binary interfaces, this
change should not be MFC'd.

Proposed by:    jeff
Reviewed by:    jeff
Discussed with: rmacklem, zach loafman @ isilon
2009-04-10 10:52:19 +00:00
jhb
520acdaf69 Add a new internal mount flag (MNTK_EXTENDED_SHARED) to indicate that a
filesystem supports additional operations using shared vnode locks.
Currently this is used to enable shared locks for open() and close() of
read-only file descriptors.
- When an ISOPEN namei() request is performed with LOCKSHARED, use a
  shared vnode lock for the leaf vnode only if the mount point has the
  extended shared flag set.
- Set LOCKSHARED in vn_open_cred() for requests that specify O_RDONLY but
  not O_CREAT.
- Use a shared vnode lock around VOP_CLOSE() if the file was opened with
  O_RDONLY and the mountpoint has the extended shared flag set.
- Adjust md(4) to upgrade the vnode lock on the vnode it gets back from
  vn_open() since it now may only have a shared vnode lock.
- Don't enable shared vnode locks on FIFO vnodes in ZFS and UFS since
  FIFO's require exclusive vnode locks for their open() and close()
  routines.  (My recent MPSAFE patches for UDF and cd9660 already included
  this change.)
- Enable extended shared operations on UFS, cd9660, and UDF.

Submitted by:	ups
Reviewed by:	pjd (ZFS bits)
MFC after:	1 month
2009-03-11 14:13:47 +00:00
jhb
47455a7b41 Move the VA_MARKATIME flag for VOP_SETATTR() out into its own VOP:
VOP_MARKATIME() since unlike the rest of VOP_SETATTR(), VA_MARKATIME
can be performed while holding a shared vnode lock (the same functionality
is done internally by VOP_READ which can run with a shared vnode lock).
Add missing locking of the vnode interlock to the ufs implementation and
remove a special note and test from the NFS client about not supporting the
feature.

Inspired by:	ups
Tested by:	pho
2009-01-21 14:42:00 +00:00
marcus
91e684d7f9 Add a new VOP, VOP_VPTOCNP, which translates a vnode to its component name
on a best-effort basis.  Teach vn_fullpath to use this new VOP if a
regular VFS cache lookup fails.  This VOP is designed to supplement the
VFS cache to provide a better chance that a vnode-to-name lookup will
succeed.

Currently, an implementation for devfs is being committed.  The default
implementation is to return ENOENT.

A big thanks to kib for the mentorship on this, and to pho for running it
through his stress test suite.

Reviewed by:	arch
Approved by:	kib
2008-12-12 00:57:38 +00:00
trasz
0ad8692247 Introduce accmode_t. This is required for NFSv4 ACLs - it will be neccessary
to add more V* constants, and the variables changed by this patch were often
being assigned to mode_t variables, which is 16 bit.

Approved by:	rwatson (mentor)
2008-10-28 13:44:11 +00:00
jhb
c343bee743 - Whitespace fix for vop_poll.
- Use the right label for vop_vptofh lock assertions so they are enforced.
2008-10-27 21:41:55 +00:00
attilio
dbf35e279f Decontextualize the couplet VOP_GETATTR / VOP_SETATTR as the passed thread
was always curthread and totally unuseful.

Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
2008-08-28 15:23:18 +00:00
dfr
79d2dfdaa6 Add the new kernel-mode NFS Lock Manager. To use it instead of the
user-mode lock manager, build a kernel with the NFSLOCKD option and
add '-k' to 'rpc_lockd_flags' in rc.conf.

Highlights include:

* Thread-safe kernel RPC client - many threads can use the same RPC
  client handle safely with replies being de-multiplexed at the socket
  upcall (typically driven directly by the NIC interrupt) and handed
  off to whichever thread matches the reply. For UDP sockets, many RPC
  clients can share the same socket. This allows the use of a single
  privileged UDP port number to talk to an arbitrary number of remote
  hosts.

* Single-threaded kernel RPC server. Adding support for multi-threaded
  server would be relatively straightforward and would follow
  approximately the Solaris KPI. A single thread should be sufficient
  for the NLM since it should rarely block in normal operation.

* Kernel mode NLM server supporting cancel requests and granted
  callbacks. I've tested the NLM server reasonably extensively - it
  passes both my own tests and the NFS Connectathon locking tests
  running on Solaris, Mac OS X and Ubuntu Linux.

* Userland NLM client supported. While the NLM server doesn't have
  support for the local NFS client's locking needs, it does have to
  field async replies and granted callbacks from remote NLMs that the
  local client has contacted. We relay these replies to the userland
  rpc.lockd over a local domain RPC socket.

* Robust deadlock detection for the local lock manager. In particular
  it will detect deadlocks caused by a lock request that covers more
  than one blocking request. As required by the NLM protocol, all
  deadlock detection happens synchronously - a user is guaranteed that
  if a lock request isn't rejected immediately, the lock will
  eventually be granted. The old system allowed for a 'deferred
  deadlock' condition where a blocked lock request could wake up and
  find that some other deadlock-causing lock owner had beaten them to
  the lock.

* Since both local and remote locks are managed by the same kernel
  locking code, local and remote processes can safely use file locks
  for mutual exclusion. Local processes have no fairness advantage
  compared to remote processes when contending to lock a region that
  has just been unlocked - the local lock manager enforces a strict
  first-come first-served model for both local and remote lockers.

Sponsored by:	Isilon Systems
PR:		95247 107555 115524 116679
MFC after:	2 weeks
2008-03-26 15:23:12 +00:00
kib
8b513f42f1 Do not assert any locks for VOP_PRINT. In particular, do not assert that
the vnode interlock is not held. vn_printf() already correctly handles
locked and unlocked vnode interlocks, and all the in-tree vop_print
methods are interlock-agnostic.

Some code calls vprintf() with the vnode interlock held, that causes
unjustified panics with INVARIANTS (ffs_syncvnode() as example).

Reported by:	Peter Holm
2008-02-26 12:16:35 +00:00
attilio
4014b55830 Axe the 'thread' argument from VOP_ISLOCKED() and lockstatus() as it is
always curthread.

As KPI gets broken by this patch, manpages and __FreeBSD_version will be
updated by further commits.

Tested by:	Andrea Barberio <insomniac at slackware dot it>
2008-02-25 18:45:57 +00:00
attilio
71b7824213 VOP_LOCK1() (and so VOP_LOCK()) and VOP_UNLOCK() are only used in
conjuction with 'thread' argument passing which is always curthread.
Remove the unuseful extra-argument and pass explicitly curthread to lower
layer functions, when necessary.

KPI results broken by this change, which should affect several ports, so
version bumping and manpage update will be further committed.

Tested by: kris, pho, Diego Sardina <siarodx at gmail dot com>
2008-01-13 14:44:15 +00:00
kib
f13486a222 Revert UF_OPENING workaround for CURRENT.
Change the VOP_OPEN(), vn_open() vnode operation and d_fdopen() cdev operation
argument from being file descriptor index into the pointer to struct file.

Proposed and reviewed by:	jhb
Reviewed by:	daichi (unionfs)
Approved by:	re (kensmith)
2007-05-31 11:51:53 +00:00
kib
162fa8dc6d Since renaming of vop_lock to _vop_lock, pre- and post-condition
function calls are no more generated for vop_lock.
Rename _vop_lock to vop_lock1 to satisfy tools/vnode_if.awk assumption
about vop naming conventions. This restores pre/post-condition calls.
2007-05-18 13:02:13 +00:00
pjd
cb2d7c85a8 Move vnode-to-file-handle translation from vfs_vptofh to vop_vptofh method.
This way we may support multiple structures in v_data vnode field within
one file system without using black magic.

Vnode-to-file-handle should be VOP in the first place, but was made VFS
operation to keep interface as compatible as possible with SUN's VFS.
BTW. Now Solaris also implements vnode-to-file-handle as VOP operation.

VFS_VPTOFH() was left for API backward compatibility, but is marked for
removal before 8.0-RELEASE.

Approved by:	mckusick
Discussed with:	many (on IRC)
Tested with:	ufs, msdosfs, cd9660, nullfs and zfs
2007-02-15 22:08:35 +00:00
kmacy
0c00ea16db change vop_lock handling to allowing tracking of callers' file and line for
acquisition of lockmgr locks

Approved by: scottl (standing in for mentor rwatson)
2006-11-13 05:51:22 +00:00
dds
840cb44e85 Remove two locking assertion entries that:
a) were incorrectly written and therefore never compiled into
assertions, and
b) were incorrectly specified and when compiled resulted in a
failed assertion.
2006-05-31 14:06:06 +00:00
dds
27cc870a3f Assertion code specifications are introduced using special character
sequences that are distinct from comments. %% is used for argument
locks; %! for pre- and post-conditions.
2006-05-30 20:49:54 +00:00
dds
1694caa758 Remove incorrect lock validation specifications that caused
failed assertions with DEBUG_VFS_LOCKS.
We should reinstate them with correct specifications, possibly
after extendng vnode_if.awk

Noted by: truckman@
2006-05-30 20:21:51 +00:00