Commit Graph

587 Commits

Author SHA1 Message Date
John Baldwin
cd4ecf3cd2 Further refine the implementation of POSIX_FADV_NOREUSE.
First, extend the changes in r230782 to better handle the common case
of using NOREUSE with sequential reads.  A NOREUSE file descriptor
will now track the last implicit DONTNEED request it made as a result
of a NOREUSE read.  If a subsequent NOREUSE read is adjacent to the
previous range, it will apply the DONTNEED request to the entire range
of both the previous read and the current read.  The effect is that
each read of a file accessed sequentially will apply the DONTNEED
request to the entire range that has been read.  This allows NOREUSE
to properly handle misaligned reads by flushing each buffer to cache
once it has been completely read.

Second, apply the same changes made to read(2) by r230782 and this
change to writes.  This provides much better performance in the
sequential write case as it allows writes to still be clustered.  It
also provides much better performance for misaligned writes.  It does
mean that NOREUSE will be generally ineffective for non-sequential
writes as the current implementation relies on a future NOREUSE
write's implicit DONTNEED request to flush the dirty buffer from the
current write.

MFC after:	2 weeks
2012-06-19 18:42:24 +00:00
Pawel Jakub Dawidek
7080f124d2 Now that dupfdopen() doesn't depend on finstall() being called earlier,
indx will never be -1 on error, as none of dupfdopen(), finstall() and
kern_capwrap() modifies it on error, but what is more important none of
those functions install and leave file at indx descriptor on error.

Leave an assert to prove my words.

MFC after:	1 month
2012-06-13 21:38:07 +00:00
Pawel Jakub Dawidek
3812dcd3de Allocate descriptor number in dupfdopen() itself instead of depending on
the caller using finstall().
This saves us the filedesc lock/unlock cycle, fhold()/fdrop() cycle and closes
a race between finstall() and dupfdopen().

MFC after:	1 month
2012-06-13 21:32:35 +00:00
Pawel Jakub Dawidek
7f35af0110 - Remove nfp variable that is not really needed.
- Update comment.
- Style nits.

MFC after:	1 month
2012-06-13 21:22:35 +00:00
Pawel Jakub Dawidek
c64dd3bae1 Remove duplicated code.
MFC after:	1 month
2012-06-13 21:15:01 +00:00
Pawel Jakub Dawidek
81424ab705 Add missing {.
MFC after:	1 month
2012-06-13 21:13:18 +00:00
Pawel Jakub Dawidek
85c1550d63 Style.
MFC after:	1 month
2012-06-13 21:11:58 +00:00
Pawel Jakub Dawidek
baf946221d There is no need to set td->td_retval[0] to -1 on error.
Confirmed by:	jhb
MFC after:	1 month
2012-06-13 21:10:00 +00:00
Pawel Jakub Dawidek
f3cd980557 Style fixes and simplifications.
MFC after:	1 month
2012-06-11 16:08:03 +00:00
John Baldwin
7ac1b61aac Split the second half of vn_open_cred() (after a vnode has been found via
a lookup or created via VOP_CREATE()) into a new vn_open_vnode() function
and use this function in fhopen() instead of duplicating code from
vn_open_cred() directly.

Tested by:	pho
Reviewed by:	kib
MFC after:	2 weeks
2012-06-08 18:32:09 +00:00
Gleb Kurtsou
76dcec5d09 Add kern_fhstat(), adjust sys_fhstat() to use it.
Extend kern_getdirentries() to accept uio segflag and optionally return
buffer residue.

Sponsored by:	Google Summer of Code 2011
2012-05-24 08:00:26 +00:00
Jaakko Heinonen
dd952f80bc The value of flags matching VNOVAL can't be supported. Return EOPNOTSUPP
from setfflags() in this case. This fixes the return value of
chflags(path, -1).

Discussed with:	bde
MFC after:	2 weeks
2012-04-20 10:08:30 +00:00
Peter Holm
39e77c4c50 Perform the parameter validation before assigning it to a signed int
variable. This fixes the problem seen with readdir(3) fuzzing.

Submitted by:	bde
MFC after:	1 week
2012-03-09 21:31:12 +00:00
Peter Holm
ffae9d4d7c Free up allocated memory used by posix_fadvise(2). 2012-03-08 20:34:13 +00:00
John Baldwin
b47f624183 Add KTR_VFS traces to track modifications to a vnode's writecount. 2012-03-08 20:27:20 +00:00
Konstantin Belousov
526d0bd547 Fix found places where uio_resid is truncated to int.
Add the sysctl debug.iosize_max_clamp, enabled by default. Setting the
sysctl to zero allows to perform the SSIZE_MAX-sized i/o requests from
the usermode.

Discussed with:	bde, das (previous versions)
MFC after:	1 month
2012-02-21 01:05:12 +00:00
Konstantin Belousov
c480f781ea Current implementations of sync(2) and syncer vnode fsync() VOP uses
mnt_noasync counter to temporary remove MNTK_ASYNC mount option, which
is needed to guarantee a synchronous completion of the initiated i/o
before syscall or VOP return.  Global removal of MNTK_ASYNC option is
harmful because not only i/o started from corresponding thread becomes
synchronous, but all i/o is synchronous on the filesystem which is
initiated during sync(2) or syncer activity.

Instead of removing MNTK_ASYNC from mnt_kern_flag, provide a local
thread flag to disable async i/o for current thread only. Use the
opportunity to move DOINGASYNC() macro into sys/vnode.h and
consistently use it through places which tested for MNTK_ASYNC.

Some testing demonstrated 60-70% improvements in run time for the
metadata-intensive operations on async-mounted UFS volumes, but still
with great deviation due to other reasons.

Reviewed by:	mckusick
Tested by:	scottl
MFC after:	2 weeks
2012-02-06 11:04:36 +00:00
Konstantin Belousov
3ab0160340 Avoid LOR between vfs_busy() lock and covered vnode lock on quotaon().
The vfs_busy() is after covered vnode lock in the global lock order, but
since quotaon() does recursive VFS call to open quota file, we usually
end up locking covered vnode after mp is busied in sys_quotactl().

Change the interface of VFS_QUOTACTL(), requiring that mp was unbusied
by fs code, and do not try to pick up vfs_busy() reference in ufs quotaon,
esp. if vfs_busy cannot succeed due to unmount being performed.

Reported and tested by:	pho
MFC after:	1 week
2012-01-08 23:06:53 +00:00
John Baldwin
f427c78b19 Fire a kevent if necessary after seeking on a regular file. This fixes a
case where a kevent would not fire on a regular file if an application read
to EOF and then seeked backwards into the file.

Reviewed by:	kib
MFC after:	2 weeks
2011-12-16 20:10:00 +00:00
Eitan Adler
3eb9ab5255 Document a large number of currently undocumented sysctls. While here
fix some style(9) issues and reduce redundancy.

PR:		kern/155491
PR:		kern/155490
PR:		kern/155489
Submitted by:	Galimov Albert <wtfcrap@mail.ru>
Approved by:	bde
Reviewed by:	jhb
MFC after:	1 week
2011-12-13 00:38:50 +00:00
Konstantin Belousov
561984be06 Fix a race between getvnode() dereferencing half-constructed file
and dupfdopen().

Reported and tested by:	pho
MFC after:	3 days
2011-11-24 20:34:06 +00:00
Ed Schouten
d3a993d46b Improve *access*() parameter name consistency.
The current code mixes the use of `flags' and `mode'. This is a bit
confusing, since the faccessat() function as a `flag' parameter to store
the AT_ flag.

Make this less confusing by using the same name as used in the POSIX
specification -- `amode'.
2011-11-19 06:35:15 +00:00
John Baldwin
7edec6214e - Split out a kern_posix_fadvise() from the posix_fadvise() system call so
it can be used by in-kernel consumers.
- Make kern_posix_fallocate() public.
- Use kern_posix_fadvise() and kern_posix_fallocate() to implement the
  freebsd32 wrappers for the two system calls.
2011-11-14 18:00:15 +00:00
John Baldwin
936c09ac0f 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
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
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
Robert Watson
fd9a5f73f6 When falloc() was broken into separate falloc_noinstall() and finstall(),
a bug was introduced in kern_openat() such that the error from the vnode
open operation was overwritten before it was passed as an argument to
dupfdopen().  This broke operations on /dev/{stdin,stdout,stderr}.  Fix
by preserving the original error number across finstall() so that it is
still available.

Approved by:	re (kib)
Reported by:	cognet
2011-08-13 16:03:40 +00:00
Jonathan Anderson
69d377fe1b Allow Capsicum capabilities to delegate constrained
access to file system subtrees to sandboxed processes.

- Use of absolute paths and '..' are limited in capability mode.
- Use of absolute paths and '..' are limited when looking up relative
  to a capability.
- When a name lookup is performed, identify what operation is to be
  performed (such as CAP_MKDIR) as well as check for CAP_LOOKUP.

With these constraints, openat() and friends are now safe in capability
mode, and can then be used by code such as the capability-mode runtime
linker.

Approved by: re (bz), mentor (rwatson)
Sponsored by: Google Inc
2011-08-13 09:21:16 +00:00
Jonathan Anderson
d6d2cfa24b Only call fdclose() on successfully-opened FDs.
Since kern_openat() now uses falloc_noinstall() and finstall() separately,
there are cases where we could get to cleanup code without ever creating
a file descriptor. In those cases, we should not call fdclose() on FD -1.

Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
2011-08-11 13:29:59 +00:00
Robert Watson
a9d2f8d84f Second-to-last commit implementing Capsicum capabilities in the FreeBSD
kernel for FreeBSD 9.0:

Add a new capability mask argument to fget(9) and friends, allowing system
call code to declare what capabilities are required when an integer file
descriptor is converted into an in-kernel struct file *.  With options
CAPABILITIES compiled into the kernel, this enforces capability
protection; without, this change is effectively a no-op.

Some cases require special handling, such as mmap(2), which must preserve
information about the maximum rights at the time of mapping in the memory
map so that they can later be enforced in mprotect(2) -- this is done by
narrowing the rights in the existing max_protection field used for similar
purposes with file permissions.

In namei(9), we assert that the code is not reached from within capability
mode, as we're not yet ready to enforce namespace capabilities there.
This will follow in a later commit.

Update two capability names: CAP_EVENT and CAP_KEVENT become
CAP_POST_KEVENT and CAP_POLL_KEVENT to more accurately indicate what they
represent.

Approved by:	re (bz)
Submitted by:	jonathan
Sponsored by:	Google Inc
2011-08-11 12:30:23 +00:00
Rick Macklem
694a586a43 Add a lock flags argument to the VFS_FHTOVP() file system
method, so that callers can indicate the minimum vnode
locking requirement. This will allow some file systems to choose
to return a LK_SHARED locked vnode when LK_SHARED is specified
for the flags argument. This patch only adds the flag. It
does not change any file system to use it and all callers
specify LK_EXCLUSIVE, so file system semantics are not changed.

Reviewed by:	kib
2011-05-22 01:07:54 +00:00
Matthew D Fleming
1ce4508f6d 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
Matthew D Fleming
5d253e418f Fix a copy/paste whitespace error. 2011-04-18 16:40:47 +00:00
Matthew D Fleming
d91f88f7f3 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
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
Konstantin Belousov
7332c129e0 Add support for executing the FreeBSD 1/i386 a.out binaries on amd64.
In particular:
- implement compat shims for old stat(2) variants and ogetdirentries(2);
- implement delivery of signals with ancient stack frame layout and
  corresponding sigreturn(2);
- implement old getpagesize(2);
- provide a user-mode trampoline and LDT call gate for lcall $7,$0;
- port a.out image activator and connect it to the build as a module
  on amd64.

The changes are hidden under COMPAT_43.

MFC after:   1 month
2011-04-01 11:16:29 +00:00
Konstantin Belousov
246d35ec91 Add O_CLOEXEC flag to open(2) and fhopen(2).
The new function fallocf(9), that is renamed falloc(9) with added
flag argument, is provided to facilitate the merge to stable branch.

Reviewed by:	jhb
MFC after:	1 week
2011-03-25 14:00:36 +00:00
Rui Paulo
79856499bd Add an extra comment to the SDT probes definition. This allows us to get
use '-' in probe names, matching the probe names in Solaris.[1]

Add userland SDT probes definitions to sys/sdt.h.

Sponsored by:	The FreeBSD Foundation
Discussed with:	rwaston [1]
2010-08-22 11:18:57 +00:00
Konstantin Belousov
aa81ae08e9 In revoke(), verify that VCHR vnode indeed belongs to devfs.
Found and tested by:	pho
MFC after:	1 week
2010-07-06 18:20:49 +00:00
Konstantin Belousov
d5ff273563 Handle a case in kern_openat() when vn_open() change file type from
DTYPE_VNODE.

Only acquire locks for O_EXLOCK/O_SHLOCK if file type is still vnode,
since we allow for fcntl(2) to process with advisory locks for
DTYPE_VNODE only. Another reason is that all fo_close() routines need to
check and release locks otherwise.

For O_TRUNC, call fo_truncate() instead of truncating the vnode.

Discussed with:	rwatson
MFC after:	2 week
2010-04-13 08:52:20 +00:00
Konstantin Belousov
5478ba7358 Remove XXX comment. Add another comment, describing why f_vnode assignment
is useful.

MFC after:	3 days
2010-04-13 08:45:55 +00:00
Ed Schouten
510ea843ba Rename st_*timespec fields to st_*tim for POSIX 2008 compliance.
A nice thing about POSIX 2008 is that it finally standardizes a way to
obtain file access/modification/change times in sub-second precision,
namely using struct timespec, which we already have for a very long
time. Unfortunately POSIX uses different names.

This commit adds compatibility macros, so existing code should still
build properly. Also change all source code in the kernel to work
without any of the compatibility macros. This makes it all a less
ambiguous.

I am also renaming st_birthtime to st_birthtim, even though it was a
local extension anyway. It seems Cygwin also has a st_birthtim.
2010-03-28 13:13:22 +00:00
Ed Schouten
0fef797f4a Actually make O_DIRECTORY work.
According to POSIX open() must return ENOTDIR when the path name does
not refer to a path name. Change vn_open() to respect this flag. This
also simplifies the Linuxolator a bit.
2010-03-21 20:43:23 +00:00
John Baldwin
9e0cda0391 Fix a comment nit.
Submitted by:	Alexander Best
2010-03-11 13:16:06 +00:00
John Baldwin
ab99e589dd Allow lseek(SEEK_END) to work on disk devices by using the DIOCGMEDIASIZE
to determine the media size.

Submitted by:	nox
MFC after:	1 week
2010-03-03 16:18:04 +00:00
Robert Watson
6c77113c9f Remove stale comment about socket buffer accounting from access(2) code.
It is the case, however, that the uidinfo of the temporary credential
set up for access(2) is not properly updated when its effective uid is
changed.

MFC after:	3 days
2010-02-27 19:57:40 +00:00
Kirk McKusick
e268f54cb4 Background:
When renaming a directory it passes through several intermediate
states. First its new name will be created causing it to have two
names (from possibly different parents). Next, if it has different
parents, its value of ".." will be changed from pointing to the old
parent to pointing to the new parent. Concurrently, its old name
will be removed bringing it back into a consistent state. When fsck
encounters an extra name for a directory, it offers to remove the
"extraneous hard link"; when it finds that the names have been
changed but the update to ".." has not happened, it offers to rewrite
".." to point at the correct parent. Both of these changes were
considered unexpected so would cause fsck in preen mode or fsck in
background mode to fail with the need to run fsck manually to fix
these problems. Fsck running in preen mode or background mode now
corrects these expected inconsistencies that arise during directory
rename. The functionality added with this update is used by fsck
running in background mode to make these fixes.

Solution:

This update adds three new fsck sysctl commands to support background
fsck in correcting expected inconsistencies that arise from incomplete
directory rename operations. They are:

setcwd(dirinode) - set the current directory to dirinode in the
    filesystem associated with the snapshot.
setdotdot(oldvalue, newvalue) - Verify that the inode number for ".."
    in the current directory is oldvalue then change it to newvalue.
unlink(nameptr, oldvalue) - Verify that the inode number associated
    with nameptr in the current directory is oldvalue then unlink it.

As with all other fsck sysctls, these new ones may only be used by
processes with appropriate priviledge.

Reported by:    	jeff
Security issues:	rwatson
2010-01-11 20:44:05 +00:00
Edward Tomasz Napierala
9d7031a6d6 Don't add VAPPEND if the file is not being opened for writing. Note that this
only affects cases where open(2) is being used improperly - i.e. when the user
specifies O_APPEND without O_WRONLY or O_RDWR.

Reviewed by:	rwatson
2009-12-08 20:47:10 +00:00
Konstantin Belousov
db17314ea4 In fhopen, vfs_ref() the mount point while vnode is unlocked, to prevent
vn_start_write(NULL, &mp) from operating on potentially freed or reused
struct mount *.

Remove unmatched vfs_rel() in cleanup.

Noted and reviewed by:	tegge
Tested by:	pho
MFC after:	3 days
2009-09-06 11:44:46 +00:00
Konstantin Belousov
4f4946d337 Honor the vfs.timestamp_precision sysctl settings for utimes(path, NULL)
and similar calls.

Obtained from:	Petr Salinger, Debian GNU/kFreeBSD, Debian bug #489894
MFC after:	3 days
2009-08-26 14:32:37 +00:00
John Baldwin
87eca70e0c Fix some LORs between vnode locks and filedescriptor table locks.
- Don't grab the filedesc lock just to read fd_cmask.
- Drop vnode locks earlier when mounting the root filesystem and before
  sanitizing stdin/out/err file descriptors during execve().

Submitted by:	kib
Approved by:	re (rwatson)
MFC after:	1 week
2009-07-31 13:40:06 +00:00
Robert Watson
b146fc1bf0 Rework vnode argument auditing to follow the same structure, in order
to avoid exposing ARG_ macros/flag values outside of the audit code in
order to name which one of two possible vnodes will be audited for a
system call.

Approved by:	re (kib)
Obtained from:	TrustedBSD Project
MFC after:	1 month
2009-07-28 21:52:24 +00:00
Edward Tomasz Napierala
c38898116a There is an optimization in chmod(1), that makes it not to call chmod(2)
if the new file mode is the same as it was before; however, this
optimization must be disabled for filesystems that support NFSv4 ACLs.
Chmod uses pathconf(2) to determine whether this is the case - however,
pathconf(2) always follows symbolic links, while the 'chmod -h' doesn't.

This change adds lpathconf(3) to make it possible to solve that problem
in a clean way.

Reviewed by:	rwatson (earlier version)
Approved by:	re (kib)
2009-07-08 15:23:18 +00:00
Robert Watson
03f7b00438 For access(2) and eaccess(2), audit the requested access mode.
Approved by:	re (audit argument blanket)
MFC after:	3 days
2009-07-01 22:47:45 +00:00
Robert Watson
422d786676 Audit the file descriptor number passed to lseek(2).
Approved by:	re (kib)
MFC after:	3 days
2009-07-01 15:37:23 +00:00
Robert Watson
c5957d6bba Fix link(2) auditing: use the second audit record path for the new object
name.

Approved by:	re (kib)
MFC after:	3 days
2009-07-01 13:22:08 +00:00
Robert Watson
14961ba789 Replace AUDIT_ARG() with variable argument macros with a set more more
specific macros for each audit argument type.  This makes it easier to
follow call-graphs, especially for automated analysis tools (such as
fxr).

In MFC, we should leave the existing AUDIT_ARG() macros as they may be
used by third-party kernel modules.

Suggested by:	brooks
Approved by:	re (kib)
Obtained from:	TrustedBSD Project
MFC after:	1 week
2009-06-27 13:58:44 +00:00
Bjoern A. Zeeb
aed2a06174 Remove the static from int hardlink_check_uid.
There is an external use in the opensolaris code.

I am not sure how this ever worked but I have seen two reports of:
	link_elf: symbol hardlink_check_uid undefined
lately.

Reported by:	Scott Ullrich (sullrich gmail.com), pfsense
Reported by:	Mister Olli (mister.olli googlemail.com)
2009-06-13 13:09:20 +00:00
Paul Saab
27bfb741a0 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
Robert Watson
bcf11e8d00 Move "options MAC" from opt_mac.h to opt_global.h, as it's now in GENERIC
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.

Discussed with:	pjd
2009-06-05 14:55:22 +00:00
Jamie Gritton
0304c73163 Add hierarchical jails. A jail may further virtualize its environment
by creating a child jail, which is visible to that jail and to any
parent jails.  Child jails may be restricted more than their parents,
but never less.  Jail names reflect this hierarchy, being MIB-style
dot-separated strings.

Every thread now points to a jail, the default being prison0, which
contains information about the physical system.  Prison0's root
directory is the same as rootvnode; its hostname is the same as the
global hostname, and its securelevel replaces the global securelevel.
Note that the variable "securelevel" has actually gone away, which
should not cause any problems for code that properly uses
securelevel_gt() and securelevel_ge().

Some jail-related permissions that were kept in global variables and
set via sysctls are now per-jail settings.  The sysctls still exist for
backward compatibility, used only by the now-deprecated jail(2) system
call.

Approved by:	bz (mentor)
2009-05-27 14:11:23 +00:00
Jeff Roberson
bf422e5f27 - Implement a lockless file descriptor lookup algorithm in
fget_unlocked().
 - Save old file descriptor tables created on expansion until
   the entire descriptor table is freed so that pointers may be
   followed without regard for expanders.
 - Mark the file zone as NOFREE so we may attempt to reference
   potentially freed files.
 - Convert several fget_locked() users to fget_unlocked().  This
   requires us to manage reference counts explicitly but reduces
   locking overhead in the common case.
2009-05-14 03:24:22 +00:00
Konstantin Belousov
3b616faed5 Prevent overflow of uio_resid.
Noted by:	jhb
MFC after:	3 days
2009-05-11 19:58:03 +00:00
Attilio Rao
dfd233edd5 Remove the thread argument from the FSD (File-System Dependent) parts of
the VFS.  Now all the VFS_* functions and relating parts don't want the
context as long as it always refers to curthread.

In some points, in particular when dealing with VOPs and functions living
in the same namespace (eg. vflush) which still need to be converted,
pass curthread explicitly in order to retain the old behaviour.
Such loose ends will be fixed ASAP.

While here fix a bug: now, UFS_EXTATTR can be compiled alone without the
UFS_EXTATTR_AUTOSTART option.

VFS KPI is heavilly changed by this commit so thirdy parts modules needs
to be recompiled.  Bump __FreeBSD_version in order to signal such
situation.
2009-05-11 15:33:26 +00:00
Robert Watson
885868cd8f 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
Ed Schouten
0eee862a54 Don't make Linux stat() open character devices to resolve its name.
The existing code calls kern_open() to resolve the vnode of a pathname
right after a stat(). This is not correct, because it causes random
character devices to be opened in /dev. This means ls'ing a tape
streamer will cause it to rewind, for example. Changes I have made:

- Add kern_statat_vnhook() to allow binary emulators to `post-process'
  struct stat, using the proper vnode.

- Remove unneeded printf's from stat() and statfs().

- Make the Linuxolator use kern_statat_vnhook(), replacing
  translate_path_major_minor_at().

- Let translate_fd_major_minor() use vp->v_rdev instead of
  vp->v_un.vu_cdev.

Result:

	crw-rw-rw- 1 root root   0, 14 Feb 20 13:54 /dev/ptmx
	crw--w---- 1 root adm  136,  0 Feb 20 14:03 /dev/pts/0
	crw--w---- 1 root adm  136,  1 Feb 20 14:02 /dev/pts/1
	crw--w---- 1 ed   tty  136,  2 Feb 20 14:03 /dev/pts/2

Before this commit, ptmx also had a major number of 136, because it
silently allocated and deallocated a pseudo-terminal. Device nodes that
cannot be opened now have proper major/minor-numbers.

Reviewed by:	kib, netchild, rdivacky (thanks!)
2009-02-20 13:05:29 +00:00
John Baldwin
ea77ff0a15 Use shared vnode locks when invoking VOP_READDIR().
MFC after:	1 month
2009-02-13 18:18:14 +00:00
Edward Tomasz Napierala
27dd8057d3 In some situations, mnt_lockref could go negative due to vfs_unbusy() being
called without calling vfs_busy() first.  This made umount(8) hang waiting
for mnt_lockref to become zero, which would never happen.

Reviewed by:	kib
Approved by:	rwatson (mentor)
Reported by:	pho
Found with:	stress2
Sponsored by:	FreeBSD Foundation
2009-02-05 08:46:18 +00:00
John Baldwin
efc65197a1 Use shared vnode locks for fchdir().
Submitted by:	ups
2009-01-23 22:13:30 +00:00
Peter Holm
ab62a2d023 Prevent overflow of uio_resid.
Approved by:	kib
2008-12-27 10:13:43 +00:00
Konstantin Belousov
548066ea66 The quotactl, statfs and fstatfs syscall implementations may dereference
NULL pointer to struct mount if the looked up vnode is reclaimed. Also,
these syscalls only mnt_ref() the mp, still allowing it to be unmounted;
only struct mount memory is kept from being reused.

Lock the vnode when doing name lookup, then reference its mount point,
unlock the vnode and vfs_busy the mountpoint. This sequence shall take
care of both races.

Reported and tested by:	pho
Discussed with:	attilio
MFC after:	1 month
2008-12-18 12:01:19 +00:00
Konstantin Belousov
6179164448 In the nfsrv_fhtovp(), after the vfs_getvfs() function found the pointer
to the fs, but before a vnode on the fs is locked, unmount may free fs
structures, causing access to destroyed data and freed memory.

Introduce a vfs_busymp() function that looks up and busies found
fs while mountlist_mtx is held. Use it in nfsrv_fhtovp() and in the
implementation of the handle syscalls.

Two other uses of the vfs_getvfs() in the vfs_subr.c, namely in
sysctl_vfs_ctl and vfs_getnewfsid seems to be ok. In particular,
sysctl_vfs_ctl is protected by Giant by being a non-sleeping sysctl
handler, that prevents Giant-locked unmount code to interfere with it.

Noted by:	tegge
Reviewed by:	dfr
Tested by:	pho
MFC after:	1 month
2008-11-29 13:34:59 +00:00
Craig Rodrigues
e506f34b24 Merge latest DTrace changes from Perforce.
Approved by:	jb
2008-11-05 19:40:36 +00:00
John Baldwin
927edcc9ba Use shared vnode locks for auditing vnode arguments as auditing only
does a VOP_GETATTR() which does not require an exclusive lock.

Reviewed by:	csjp, rwatson
2008-11-04 22:31:04 +00:00
John Baldwin
21fc02d271 Use shared vnode locks instead of exclusive vnode locks for the access(),
chdir(), chroot(), eaccess(), fpathconf(), fstat(), fstatfs(), lseek()
(when figuring out the current size of the file in the SEEK_END case),
pathconf(), readlink(), and statfs() system calls.

Submitted by:	ups (mostly)
Tested by:	pho
MFC after:	1 month
2008-11-03 20:31:00 +00:00
Attilio Rao
83b3bdbc8a Improve VFS locking:
- Implement real draining for vfs consumers by not relying on the
  mnt_lock and using instead a refcount in order to keep track of lock
  requesters.
- Due to the change above, remove the mnt_lock lockmgr because it is now
  useless.
- Due to the change above, vfs_busy() is no more linked to a lockmgr.
  Change so its KPI by removing the interlock argument and defining 2 new
  flags for it: MBF_NOWAIT which basically replaces the LK_NOWAIT of the
  old version (which was unlinked from the lockmgr alredy) and
  MBF_MNTLSTLOCK which provides the ability to drop the mountlist_mtx
  once the mnt interlock is held (ability still desired by most consumers).
- The stub used into vfs_mount_destroy(), that allows to override the
  mnt_ref if running for more than 3 seconds, make it totally useless.
  Remove it as it was thought to work into older versions.
  If a problem of "refcount held never going away" should appear, we will
  need to fix properly instead than trust on such hackish solution.
- Fix a bug where returning (with an error) from dounmount() was still
  leaving the MNTK_MWAIT flag on even if it the waiters were actually
  woken up. Just a place in vfs_mount_destroy() is left because it is
  going to recycle the structure in any case, so it doesn't matter.
- Remove the markercnt refcount as it is useless.

This patch modifies VFS ABI and breaks KPI for vfs_busy() so manpages and
__FreeBSD_version will be modified accordingly.

Discussed with:	kib
Tested by:	pho
2008-11-02 10:15:42 +00:00
Edward Tomasz Napierala
15bc6b2bd8 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
John Baldwin
6239752624 Whitespace fix. 2008-10-23 21:50:16 +00:00
Dag-Erling Smørgrav
1ede983cc9 Retire the MALLOC and FREE macros. They are an abomination unto style(9).
MFC after:	3 months
2008-10-23 15:53:51 +00:00
John Baldwin
63f8fe9e8b Split the copyout of *base at the end of getdirentries() out leaving the
rest in kern_getdirentries().  Use kern_getdirentries() to implement
freebsd32_getdirentries().  This fixes a bug where calls to getdirentries()
in 32-bit binaries would trash the 4 bytes after the 'long base' in
userland.

Submitted by:	ups
MFC after:	1 week
2008-10-22 21:55:48 +00:00
Pawel Jakub Dawidek
2765482b7f When setting error to EINVAL in 'fvp == tdvp' case, jump to out label,
because if not, the error will be later overwritten by
mac_vnode_check_rename_to() call.

Reviewed by:	rwatson
2008-09-01 10:11:39 +00:00
Attilio Rao
59d4932531 Decontextualize vfs_busy(), vfs_unbusy() and vfs_mount_alloc() functions.
Manpages are updated accordingly.

Tested by:	Diego Sardina <siarodx at gmail dot com>
2008-08-31 14:26:08 +00:00
Attilio Rao
0359a12ead 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
Robert Watson
3319d71265 If S_IFIFO is passed to mknod(2), invoke kern_mkfifoat(9) to create a
FIFO, as required by SUSv3.  No specific privilege check is performed
in this case, as FIFOs may be created by unprivileged processes
(subject to the normal file system name space restrictions that may be
in place).

Unlike the Apple implementation, we reject requests to create a FIFO
using mknod(2) if there is a non-zero dev argument to the system call,
which is permitted by the Open Group specification ("... undefined
...").  We might want to revise this if we find it causes
compatibility problems for applications in practice.

PR:		kern/74242, kern/68459
Obtained from:	Apple, Inc.
MFC after:	3 weeks
2008-06-22 21:51:32 +00:00
Don Lewis
8a3724388b vfs_syscalls.c 1.452 mistakenly swapped the behavior of chown() and lchown(). 2008-04-07 00:29:32 +00:00
Konstantin Belousov
e4193f25cb Implement the
openat(2), faccessat(2), fchmodat(2), fchownat(2), fstatat(2),
	futimesat(2), linkat(2), mkdirat(2), mkfifoat(2), mknodat(2),
	readlinkat(2), renameat(2), symlinkat(2)
syscalls.

Based on the submission by rdivacky,
	sponsored by Google Summer of Code 2007
Reviewed by:	rwatson, rdivacky
Tested by:	pho
2008-03-31 12:04:20 +00:00
Konstantin Belousov
e314f69fff Add the support for the O_EXEC open(2) mode, as specified by the
POSIX Extended API Set Part 2 extension specification.

Reviewed by:	rwatson, rdivacky
Tested by:	pho
2008-03-31 11:57:18 +00:00
Dag-Erling Smørgrav
60e15db992 This patch adds a new ktrace(2) record type, KTR_STRUCT, whose payload
consists of the null-terminated name and the contents of any structure
you wish to record.  A new ktrstruct() function constructs and emits a
KTR_STRUCT record.  It is accompanied by convenience macros for struct
stat and struct sockaddr.

In kdump(1), KTR_STRUCT records are handled by a dispatcher function
that runs stringent sanity checks on its contents before handing it
over to individual decoding funtions for each type of structure.
Currently supported structures are struct stat and struct sockaddr for
the AF_INET, AF_INET6 and AF_UNIX families; support for AF_APPLETALK
and AF_IPX is present but disabled, as I am unable to test it properly.

Since 's' was already taken, the letter 't' is used by ktrace(1) to
enable KTR_STRUCT trace points, and in kdump(1) to enable their
decoding.

Derived from patches by Andrew Li <andrew2.li@citi.com>.

PR:		kern/117836
MFC after:	3 weeks
2008-02-23 01:01:49 +00:00
Ruslan Ermilov
5f56182b6f Change readlink(2)'s return type and type of the last argument
to match POSIX.

Prodded by:	Alexey Lyashkov
2008-02-12 20:09:04 +00:00
Attilio Rao
22db15c06f 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
Attilio Rao
cb05b60a89 vn_lock() is currently only used with the 'curthread' passed as argument.
Remove this argument and pass curthread directly to underlying
VOP_LOCK1() VFS method. This modify makes the code cleaner and in
particular remove an annoying dependence helping next lockmgr() cleanup.
KPI results, obviously, changed.

Manpage and FreeBSD_version will be updated through further commits.

As a side note, would be valuable to say that next commits will address
a similar cleanup about VFS methods, in particular vop_lock1 and
vop_unlock.

Tested by:	Diego Sardina <siarodx at gmail dot com>,
		Andrea Di Pasquale <whyx dot it at gmail dot com>
2008-01-10 01:10:58 +00:00
John Baldwin
e46502943a Make ftruncate a 'struct file' operation rather than a vnode operation.
This makes it possible to support ftruncate() on non-vnode file types in
the future.
- 'struct fileops' grows a 'fo_truncate' method to handle an ftruncate() on
  a given file descriptor.
- ftruncate() moves to kern/sys_generic.c and now just fetches a file
  object and invokes fo_truncate().
- The vnode-specific portions of ftruncate() move to vn_truncate() in
  vfs_vnops.c which implements fo_truncate() for vnode file types.
- Non-vnode file types return EINVAL in their fo_truncate() method.

Submitted by:	rwatson
2008-01-07 20:05:19 +00:00
Jeff Roberson
397c19d175 Remove explicit locking of struct file.
- Introduce a finit() which is used to initailize the fields of struct file
   in such a way that the ops vector is only valid after the data, type,
   and flags are valid.
 - Protect f_flag and f_count with atomic operations.
 - Remove the global list of all files and associated accounting.
 - Rewrite the unp garbage collection such that it no longer requires
   the global list of all files and instead uses a list of all unp sockets.
 - Mark sockets in the accept queue so we don't incorrectly gc them.

Tested by:	kris, pho
2007-12-30 01:42:15 +00:00
Robert Watson
30d239bc4c Merge first in a series of TrustedBSD MAC Framework KPI changes
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:

  mac_<object>_<method/action>
  mac_<object>_check_<method/action>

The previous naming scheme was inconsistent and mostly
reversed from the new scheme.  Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier.  Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods.  Also simplify, slightly,
some entry point names.

All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.

Sponsored by:	SPARTA (original patches against Mac OS X)
Obtained from:	TrustedBSD Project, Apple Computer
2007-10-24 19:04:04 +00:00
Robert Watson
45e0f3d63d Rename mac_check_vnode_delete() MAC Framework and MAC Policy entry
point to mac_check_vnode_unlink(), reflecting UNIX naming conventions.

This is the first of several commits to synchronize the MAC Framework
in FreeBSD 7.0 with the MAC Framework as it will appear in Mac OS X
Leopard.

Reveiwed by:    csjp, Samy Bahra <sbahra at gwu dot edu>
Submitted by:   Jacques Vidrine <nectar at apple dot com>
Obtained from:  Apple Computer, Inc.
Sponsored by:   SPARTA, SPAWAR
Approved by:    re (bmah)
2007-09-10 00:00:18 +00:00
John Baldwin
cc479dda4a Rework the routines to convert a 5.x+ statfs structure (with fixed-size
64-bit counters) to a 4.x statfs structure (with long-sized counters).
- For block counters, we scale up the block size sufficiently large so
  that the resulting block counts fit into a the long-sized (long for the
  ABI, so 32-bit in freebsd32) counters.  In 4.x the NFS client's statfs
  VOP did this already.  This can lie about the block size to 4.x binaries,
  but it presents a more accurate picture of the ratios of free and
  available space.
- For non-block counters, fix the freebsd32 stats converter to cap the
  values at INT32_MAX rather than losing the upper 32-bits to match the
  behavior of the 4.x statfs conversion routine in vfs_syscalls.c

Approved by:	re (kensmith)
2007-08-28 20:28:12 +00:00
Peter Wemm
c2815ad564 Add freebsd6_ wrappers for mmap/lseek/pread/pwrite/truncate/ftruncate
Approved by: re (kensmith)
2007-07-04 22:57:21 +00:00
Robert Watson
32f9753cfb Eliminate now-unused SUSER_ALLOWJAIL arguments to priv_check_cred(); in
some cases, move to priv_check() if it was an operation on a thread and
no other flags were present.

Eliminate caller-side jail exception checking (also now-unused); jail
privilege exception code now goes solely in kern_jail.c.

We can't yet eliminate suser() due to some cases in the KAME code where
a privilege check is performed and then used in many different deferred
paths.  Do, however, move those prototypes to priv.h.

Reviewed by:	csjp
Obtained from:	TrustedBSD Project
2007-06-12 00:12:01 +00:00
Konstantin Belousov
9e223287c0 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
Konstantin Belousov
5c76452f8f Mark the filedescriptor table entries with VOP_OPEN being performed for them
as UF_OPENING. Disable closing of that entries. This should fix the crashes
caused by devfs_open() (and fifo_open()) dereferencing struct file * by
index, while the filedescriptor is closed by parallel thread.

Idea by:	tegge
Reviewed by:	tegge (previous version of patch)
Tested by:	Peter Holm
Approved by:	re (kensmith)
MFC after:	3 weeks
2007-05-04 14:23:29 +00:00