Commit Graph

230 Commits

Author SHA1 Message Date
David Xu
5ff2bb52cc I am comparing current pipe code with the one in 8.3-STABLE r236165,
I found 8.3 is a history BSD version using socket to implement FIFO
pipe, it uses per-file seqcount to compare with writer generation
stored in per-pipe object. The concept is after all writers are gone,
the pipe enters next generation, all old readers have not closed the
pipe should get the indication that the pipe is disconnected, result
is they should get EPIPE, SIGPIPE or get POLLHUP in poll().
But newcomer should not know that previous writters were gone, it
should treat it as a fresh session.
I am trying to bring back FIFO pipe to history behavior. It is still
unclear that if single EOF flag can represent SBS_CANTSENDMORE and
SBS_CANTRCVMORE which socket-based version is using, but I have run
the poll regression test in tool directory, output is same as the one
on 8.3-STABLE now.
I think the output "not ok 18 FIFO state 6b: poll result 0 expected 1.
expected POLLHUP; got 0" might be bogus, because newcomer should not
know that old writers were gone. I got the same behavior on Linux.
Our implementation always return POLLIN for disconnected pipe even it
should return POLLHUP, but I think it is not wise to remove POLLIN for
compatible reason, this is our history behavior.

Regression test: /usr/src/tools/regression/poll
2012-07-31 05:48:35 +00:00
David Xu
12a480fa41 When a thread is blocked in direct write state, it only sets PIPE_DIRECTW
flag but not PIPE_WANTW, but FIFO pipe code does not understand this internal
state, when a FIFO peer reader closes the pipe, it wants to notify the writer,
it checks PIPE_WANTW, if not set, it skips calling wakeup(), so blocked writer
never noticed the case, but in general, the writer should return from the
syscall with EPIPE error code and may get SIGPIPE signal. Setting the
PIPE_WANTW fixed problem, or you can turn off direct write, it should fix the
problem too. This bug is found by PR/170203.

Another bug in FIFO pipe code is when peer closes the pipe, another end which
is being blocked in select() or poll() is not notified, it missed to call
pipeselwakeup().

Third problem is found in poll regression test, the existing code can not
pass 6b,6c,6d tests, but FreeBSD-4 works. This commit does not fix the
problem, I still need to study more to find the cause.

PR: 170203
Tested by: Garrett Copper < yanegomi at gmail dot com >
2012-07-31 02:00:37 +00:00
Jung-uk Kim
d69a426fce - Implement pipe2 syscall for Linuxulator. This syscall appeared in 2.6.27
but GNU libc used it without checking its kernel version, e. g., Fedora 10.
- Move pipe(2) implementation for Linuxulator from MD files to MI file,
sys/compat/linux/linux_file.c.  There is no MD code for this syscall at all.
- Correct an argument type for pipe() from l_ulong * to l_int *.  Probably
this was the source of MI/MD confusion.

Reviewed by:	emulation
2012-04-16 21:22:02 +00:00
Konstantin Belousov
b80dcb55aa Remove fifo.h. The only used function declaration from the header is
migrated to sys/vnode.h.

Submitted by:	gianni
2012-03-11 12:19:58 +00:00
Konstantin Belousov
f950879e16 The pipe_poll() performs lockless access to the vnode to test
fifo_iseof() condition, allowing the v_fifoinfo to be reset and freed
by fifo_cleanup().

Precalculate EOF at the places were fo_wgen is changed, and cache the
state in a new pipe state flag PIPE_SAMEWGEN.

Reported and tested by:	bf
Submitted by:	gianni
MFC after:	1 week (a backport)
2012-03-07 07:31:50 +00:00
Konstantin Belousov
e7f19c3d81 pipe_read(): change the type of size to int, and remove signed clamp.
pipe_write(): change the type of desiredsize back to int, its value fits.

Requested by: bde
MFC after:    3 weeks
2012-03-04 15:09:01 +00:00
Dimitry Andric
ac382cb7f1 Change definition of pipe_chmod() from K&R to C99, to avoid the
following clang warning:

sys/kern/sys_pipe.c:1556:10: error: promoted type 'int' of K&R function parameter is not compatible with the parameter type 'mode_t'
      (aka 'unsigned short') declared in a previous prototype [-Werror]
        mode_t mode;
               ^
sys/kern/sys_pipe.c:155:19: note: previous declaration is here
static fo_chmod_t       pipe_chmod;
                        ^
2012-02-28 21:45:21 +00:00
Jilles Tjoelker
581400dfed Fix fchmod() and fchown() on fifos.
The new fifo implementation in r232055 broke fchmod() and fchown() on fifos.
Postfix needs this.

Submitted by:	gianni
Reported by:	dougb
2012-02-26 15:14:29 +00:00
Kip Macy
11ac7ec076 merge pipe and fifo implementations
Also reviewed by: jhb, jilles (initial revision)
Tested by: pho, jilles

Submitted by:	gianni
Reviewed by:	bde
2012-02-23 18:37:30 +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
Jilles Tjoelker
6d1c58f8a2 Fix select/poll/kqueue for write on reverse direction before first write.
The reverse direction of a pipe is lazily allocated on the first write in
that direction (because pipes are usually used in one direction only).  A
special case is needed to ensure the pipe appears writable before the first
write because there are 0 bytes of pending data in 0 bytes of buffer space
at that point, leaving 0 bytes of data that can be written with the normal
code.

Note that the first write returns [ENOMEM] if kern.ipc.maxpipekva is
exceeded and does not block or return [EAGAIN], so selecting true for write
is correct even in that case.

PR:		kern/93685
Submitted by:	gianni
MFC after:	2 weeks
2011-12-14 22:26:39 +00:00
Konstantin Belousov
93c26de0ad Most users of pipe(2) do not call fstat(2) on the returned pipe descriptors.
Optimize for the case, by lazily allocating the pipe inode number at the
fstat(2) time. If alloc_unr(9) returns failure, do not fail fstat(2), since
uses of inode numbers are even rare then fstat(2), but provide zero inode
forever. Note that alloc_unr() failure is unlikely due to total number
of pipes in the system limited by the number of file descriptors.

Based on the submission by:	gianni
MFC after:	2 weeks
2011-12-06 11:24:03 +00:00
Konstantin Belousov
5ed954efd1 If alloc_unr() call in the pipe_create() failed, then pipe->pipe_ino is
-1. But, because ino_t is unsigned, this case was not covered by the
test ino > 0 in pipeclose(), leading to the free_unr(-1). Fix it by
explicitely comparing with 0 and -1. [1]

Do no access freed memory, the inode number was cached to prevent access
to cpipe after it possibly was freed, but I failed to commit the right
patch.

Noted by:	gianni [1]
Pointy hat to:	kib
MFC after:	3 days
2011-12-01 11:36:41 +00:00
Konstantin Belousov
a101072d7f Supply unique (st_dev, st_ino) value pair for the fstat(2) done on the pipes.
Reviewed by:	jhb, Peter Jeremy <peterjeremy acm org>
MFC after:	2 weeks
2011-10-05 16:56:06 +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
Attilio Rao
6aba400a70 Fix a deficiency in the selinfo interface:
If a selinfo object is recorded (via selrecord()) and then it is
quickly destroyed, with the waiters missing the opportunity to awake,
at the next iteration they will find the selinfo object destroyed,
causing a PF#.

That happens because the selinfo interface has no way to drain the
waiters before to destroy the registered selinfo object. Also this
race is quite rare to get in practice, because it would require a
selrecord(), a poll request by another thread and a quick destruction
of the selrecord()'ed selinfo object.

Fix this by adding the seldrain() routine which should be called
before to destroy the selinfo objects (in order to avoid such case),
and fix the present cases where it might have already been called.
Sometimes, the context is safe enough to prevent this type of race,
like it happens in device drivers which installs selinfo objects on
poll callbacks. There, the destruction of the selinfo object happens
at driver detach time, when all the filedescriptors should be already
closed, thus there cannot be a race.
For this case, mfi(4) device driver can be set as an example, as it
implements a full correct logic for preventing this from happening.

Sponsored by:	Sandvine Incorporated
Reported by:	rstone
Tested by:	pluknet
Reviewed by:	jhb, kib
Approved by:	re (bz)
MFC after:	3 weeks
2011-08-25 15:51:54 +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
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
Alan Cox
09a196a7de Update a comment. The sending process has not mapped the buffer pages
since before r127501.  Strictly speaking, the buffer pages are not
"wired".  They remain in the paging queues.  However, they are pinned in
memory using vm_page_hold().
2011-03-20 15:04:43 +00:00
Alan Cox
82de724fe1 Introduce and use a new VM interface for temporarily pinning pages. This
new interface replaces the combined use of vm_fault_quick() and
pmap_extract_and_hold() throughout the kernel.

In collaboration with:	kib@
2010-12-25 21:26:56 +00:00
Alan Cox
8c22654d7e Implement and use a single optimized function for unholding a set of pages.
Reviewed by:	kib@
2010-12-17 22:41:22 +00:00
Alan Cox
7d1d2ef60a Update a comment: It no longer makes sense to talk about the page queues
lock here.
2010-05-08 23:01:47 +00:00
Kip Macy
2965a45315 On Alan's advice, rather than do a wholesale conversion on a single
architecture from page queue lock to a hashed array of page locks
(based on a patch by Jeff Roberson), I've implemented page lock
support in the MI code and have only moved vm_page's hold_count
out from under page queue mutex to page lock. This changes
pmap_extract_and_hold on all pmaps.

Supported by: Bitgravity Inc.

Discussed with: alc, jeffr, and kib
2010-04-30 00:46:43 +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
Robert Watson
e76d823b81 Use C99 initialization for struct filterops.
Obtained from:	Mac OS X
Sponsored by:	Apple Inc.
MFC after:	3 weeks
2009-09-12 20:03:45 +00:00
Konstantin Belousov
7f5dff5064 Fix poll(2) and select(2) for named pipes to return "ready for read"
when all writers, observed by reader, exited. Use writer generation
counter for fifo, and store the snapshot of the fifo generation in the
f_seqcount field of struct file, that is otherwise unused for fifos.
Set FreeBSD-undocumented POLLINIGNEOF flag only when file f_seqcount is
equal to fifo' fi_wgen, and revert r89376.

Fix POLLINIGNEOF for sockets and pipes, and return POLLHUP for them.
Note that the patch does not fix not returning POLLHUP for fifos.

PR:	kern/94772
Submitted by:	bde (original version)
Reviewed by:	rwatson, jilles
Approved by:	re (kensmith)
MFC after:	6 weeks (might be)
2009-07-07 09:43:44 +00:00
Konstantin Belousov
d8b0556c6d Adapt vfs kqfilter to the shared vnode lock used by zfs write vop. Use
vnode interlock to protect the knote fields [1]. The locking assumes
that shared vnode lock is held, thus we get exclusive access to knote
either by exclusive vnode lock protection, or by shared vnode lock +
vnode interlock.

Do not use kl_locked() method to assert either lock ownership or the
fact that curthread does not own the lock. For shared locks, ownership
is not recorded, e.g. VOP_ISLOCKED can return LK_SHARED for the shared
lock not owned by curthread, causing false positives in kqueue subsystem
assertions about knlist lock.

Remove kl_locked method from knlist lock vector, and add two separate
assertion methods kl_assert_locked and kl_assert_unlocked, that are
supposed to use proper asserts. Change knlist_init accordingly.

Add convenience function knlist_init_mtx to reduce number of arguments
for typical knlist initialization.

Submitted by:	jhb [1]
Noted by:	jhb [2]
Reviewed by:	jhb
Tested by:	rnoland
2009-06-10 20:59:32 +00:00
Colin Percival
9a1bde1808 Prevent integer overflow in direct pipe write code from circumventing
virtual-to-physical page lookups. [09:09]

Add missing permissions check for SIOCSIFINFO_IN6 ioctl. [09:10]

Fix buffer overflow in "autokey" negotiation in ntpd(8). [09:11]

Approved by:	so (cperciva)
Approved by:	re (not really, but SVN wants this...)
Security:	FreeBSD-SA-09:09.pipe
Security:	FreeBSD-SA-09:10.ipv6
Security:	FreeBSD-SA-09:11.ntpd
2009-06-10 10:31:11 +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
John Baldwin
64ecd1399f - Make maxpipekva a signed long rather than an unsigned long as overflow
is more likely to be noticed with signed types.
- Make amountpipekva a long as well to match maxpipekva.

Discussed with:	bde
2009-03-10 21:28:43 +00:00
John Baldwin
5bd65606f4 Adjust some variables (mostly related to the buffer cache) that hold
address space sizes to be longs instead of ints.  Specifically, the follow
values are now longs: runningbufspace, bufspace, maxbufspace,
bufmallocspace, maxbufmallocspace, lobufspace, hibufspace, lorunningspace,
hirunningspace, maxswzone, maxbcache, and maxpipekva.  Previously, a
relatively small number (~ 44000) of buffers set in kern.nbuf would result
in integer overflows resulting either in hangs or bogus values of
hidirtybuffers and lodirtybuffers.  Now one has to overflow a long to see
such problems.  There was a check for a nbuf setting that would cause
overflows in the auto-tuning of nbuf.  I've changed it to always check and
cap nbuf but warn if a user-supplied tunable would cause overflow.

Note that this changes the ABI of several sysctls that are used by things
like top(1), etc., so any MFC would probably require a some gross shims
to allow for that.

MFC after:	1 month
2009-03-09 19:35:20 +00:00
Ed Schouten
ab0d10f68e Several cleanups related to pipe(2).
- Use `fildes[2]' instead of `*fildes' to make more clear that pipe(2)
  fills an array with two descriptors.

- Remove EFAULT from the manual page. Because of the current calling
  convention, pipe(2) raises a segmentation fault when an invalid
  address is passed.

- Introduce kern_pipe() to make it easier for binary emulations to
  implement pipe(2).

- Make Linux binary emulation use kern_pipe(), which means we don't have
  to recover td_retval after calling the FreeBSD system call.

Approved by:	rdivacky
Discussed on:	arch
2008-11-11 14:55:59 +00:00
Konstantin Belousov
741b6cf8a5 Another problem caused by the knlist_cleardel() potentially dropping
PIPE_MTX().

Since the pipe_present is cleared before (potentially) sleeping, the
second thread may enter the pipeclose() for the reciprocal pipe end.
The test at the end of the pipeclose() for the pipe_present == 0 would
succeed, allowing the second thread to free the pipe memory. First
threads then accesses the freed memory after being woken up.

Properly track the closing state of the pipe in the pipe_present.
Introduce the intermediate state that marks the pipe as mostly
dismantled but might be sleeping waiting for the knote list to be
cleared. Free the pipe pair memory only when both ends pass that point.

Debugging help and tested by:	pho
Discussed with:	jmg
MFC after:	2 weeks
2008-05-23 11:14:03 +00:00
Konstantin Belousov
e2e1693f15 Destruction of the pipe calls knlist_cleardel() to remove the knotes
monitoring the pipe. The code sets pipe_present = 0 and enters
knlist_cleardel(), where the PIPE_MTX might be dropped when knl->kl_list
cannot be cleared due to influx knotes.

If the following often encountered code fragment
                if (!(kn->kn_status & KN_DETACHED))
                        kn->kn_fop->f_detach(kn);
                knote_drop(kn, td); [1]
is executed while the knlist lock is dropped, then the knote memory is freed
by the knote_drop() without knote being removed from the knlist, since
the filt_pipedetach() contains the following:
        if (kn->kn_filter == EVFILT_WRITE) {
                if (!cpipe->pipe_peer->pipe_present) {
                        PIPE_UNLOCK(cpipe);
                        return;

Now, the memory may be reused in the zone, causing the access to the
freed memory. I got the panics caused by the marker knote appearing on
the knlist, that, I believe, manifestation of the issue. In the Peter
Holm test scenarious, we got unkillable processes too.

The pipe_peer that has the knote for write shall be present. Ignore the
pipe_present value for EVFILT_WRITE in filt_pipedetach().

Debugging help and tested by:	pho
Discussed with:	jmg
MFC after:	2 weeks
2008-05-23 11:09:50 +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
Jeff Roberson
ace8398da0 Refactor select to reduce contention and hide internal implementation
details from consumers.

 - Track individual selecters on a per-descriptor basis such that there
   are no longer collisions and after sleeping for events only those
   descriptors which triggered events must be rescaned.
 - Protect the selinfo (per descriptor) structure with a mtx pool mutex.
   mtx pool mutexes were chosen to preserve api compatibility with
   existing code which does nothing but bzero() to setup selinfo
   structures.
 - Use a per-thread wait channel rather than a global wait channel.
 - Hide select implementation details in a seltd structure which is
   opaque to the rest of the kernel.
 - Provide a 'selsocket' interface for those kernel consumers who wish to
   select on a socket when they have no fd so they no longer have to
   be aware of select implementation details.

Tested by:	kris
Reviewed on:	arch
2007-12-16 06:21:20 +00:00
Jean-Sébastien Pédron
4b5b09e744 The kernel uses two ways to write data on a pipe:
o  buffered write, for chunks smaller than PIPE_MINDIRECT bytes
    o  direct write, for everything else

A call to writev(2) may receive struct iov of various size and the
kernel may have to switch from one solution to the other. Before doing
this, it must wake reader processes and any select/poll/kqueue up.

This commit fixes a bug where select/poll/kqueue are not triggered
when switching from buffered write to direct write. It adds calls to
pipeselwakeup().

I give more details on freebsd-arch@:
http://lists.freebsd.org/pipermail/freebsd-arch/2007-September/006790.html

This should fix issues with Erlang (lang/erlang) and kqueue.

Reported by:	Rickard Green (Erlang)
2007-11-19 15:05:20 +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
097e1ea87f Remove amountpipes counter for pipes -- this replicates the function of
existing UMA statistics for pipes, and allows us to get rid of both the
per-pipe dtor and two atomic operations per pipe required to maintain
the counter.
2007-05-27 17:33:10 +00:00
Robert Watson
873fbcd776 Further system call comment cleanup:
- Remove also "MP SAFE" after prior "MPSAFE" pass. (suggested by bde)
- Remove extra blank lines in some cases.
- Add extra blank lines in some cases.
- Remove no-op comments consisting solely of the function name, the word
  "syscall", or the system call name.
- Add punctuation.
- Re-wrap some comments.
2007-03-05 13:10:58 +00:00
Pawel Jakub Dawidek
ce0d4ed4c2 Use pipe_direct_write() optimization only if the data is in process' memory.
This fixes sending data through pipe from the kernel.

Fix suggested by:	rwatson
2006-12-19 12:52:22 +00:00
Robert Watson
aed5570872 Complete break-out of sys/sys/mac.h into sys/security/mac/mac_framework.h
begun with a repo-copy of mac.h to mac_framework.h.  sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.

This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.

Obtained from:	TrustedBSD Project
Sponsored by:	SPARTA
2006-10-22 11:52:19 +00:00
Robert Watson
b37ffd3189 Move some functions and definitions from uipc_socket2.c to uipc_socket.c:
- Move sonewconn(), which creates new sockets for incoming connections on
  listen sockets, so that all socket allocate code is together in
  uipc_socket.c.

- Move 'maxsockets' and associated sysctls to uipc_socket.c with the
  socket allocation code.

- Move kern.ipc sysctl node to uipc_socket.c, add a SYSCTL_DECL() for it
  to sysctl.h and remove lots of scattered implementations in various
  IPC modules.

- Sort sodealloc() after soalloc() in uipc_socket.c for dependency order
  reasons.  Statisticize soalloc() and sodealloc() as they are now
  required only in uipc_socket.c, and are internal to the socket
  implementation.

After this change, socket allocation and deallocation is entirely
centralized in one file, and uipc_socket2.c consists entirely of socket
buffer manipulation and default protocol switch functions.

MFC after:	1 month
2006-06-10 14:34:07 +00:00
Gleb Smirnoff
61fb9bd80c - In pipe() return the error returned by pipe_create(), rather then
hardcoded ENFILES, which is incorrect. pipe_create() can fail due
  to ENOMEM.
- Update manual page, describing ENOMEM return code.

Reviewed by:	arch
2006-01-30 08:25:04 +00:00
Xin LI
6ba9ec2d09 In pipe_write(): when uiomove() fails, do not spin on it forever.
Submitted by:	Kostik Belousov <kostikbel at gmail.com> on -current@
Message-ID:	<20051216151016.GE84442@deviant.zoral.local>
MFC After:	3 weeks
2005-12-16 18:32:39 +00:00
Suleiman Souhlal
571dcd15e2 Fix the recent panics/LORs/hangs created by my kqueue commit by:
- Introducing the possibility of using locks different than mutexes
for the knlist locking. In order to do this, we add three arguments to
knlist_init() to specify the functions to use to lock, unlock and
check if the lock is owned. If these arguments are NULL, we assume
mtx_lock, mtx_unlock and mtx_owned, respectively.

- Using the vnode lock for the knlist locking, when doing kqueue operations
on a vnode. This way, we don't have to lock the vnode while holding a
mutex, in filt_vfsread.

Reviewed by:	jmg
Approved by:	re (scottl), scottl (mentor override)
Pointyhat to:	ssouhlal
Will be happy:	everyone
2005-07-01 16:28:32 +00:00
Mike Silbersack
6792415119 Rearrange the kninit calls for both directions of a pipe so that
they both happen before pipe backing allocation occurs.  Previously,
a pipe memory shortage would cause a panic due to a KNOTE call
on an uninitialized si_note.

Reported by:	Peter Holm
MFC after:	1 week
2005-01-17 07:56:28 +00:00
Warner Losh
9454b2d864 /* -> /*- for copyright notices, minor format tweaks as necessary 2005-01-06 23:35:40 +00:00
Robert Watson
436cac68e6 Correct a bug introduced in sys_pipe.c:1.179: in pipe_ioctl(),
release the pipe mutex before calling fsetown(), as fsetown()
may block.  The sigio code protects the pipe sigio data using
its own mutex, and the pipe reference count held by the caller
will prevent the pipe from being prematurely garbage-collected.

Discovered by:	imp
2004-11-23 22:15:08 +00:00