Commit Graph

95 Commits

Author SHA1 Message Date
Matthew Dillon
0cddd8f023 With Alfred's permission, remove vm_mtx in favor of a fine-grained approach
(this commit is just the first stage).  Also add various GIANT_ macros to
formalize the removal of Giant, making it easy to test in a more piecemeal
fashion. These macros will allow us to test fine-grained locks to a degree
before removing Giant, and also after, and to remove Giant in a piecemeal
fashion via sysctl's on those subsystems which the authors believe can
operate without Giant.
2001-07-04 16:20:28 +00:00
David Malone
db3cc2d09f Don't dereference a NULL pointer if we fail to get a sendfilebuf. 2001-06-24 12:27:30 +00:00
John Baldwin
9d127f9ffb Add vm locking to sendfile(2) and sf_buf_free().
Reported by:	Tamiji Homma <thomma@BayNetworks.com>
Tested by:	Tamiji Homma <thomma@BayNetworks.com>
2001-05-25 19:23:04 +00:00
Mark Murray
fb919e4d5a Undo part of the tangle of having sys/lock.h and sys/mutex.h included in
other "system" header files.

Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.

Sort sys/*.h includes where possible in affected files.

OK'ed by:	bde (with reservations)
2001-05-01 08:13:21 +00:00
Greg Lehey
60fb0ce365 Revert consequences of changes to mount.h, part 2.
Requested by:	bde
2001-04-29 02:45:39 +00:00
Alfred Perlstein
06336fb26d Sendfile is documented to return 0 on success, however if when a
sf_hdtr is used to provide writev(2) style headers/trailers on the
sent data the return value is actually either the result of writev(2)
from the trailers or headers of no tailers are specified.

Fix sendfile to comply with the documentation, by returning 0 on
success.

Ok'd by: dg
2001-04-26 00:14:14 +00:00
Greg Lehey
d98dc34f52 Correct #includes to work with fixed sys/mount.h. 2001-04-23 09:05:15 +00:00
Bosko Milekic
4bde2ac539 Fix is a similar race condition as existed in the mbuf code. When we go
into an interruptable sleep and we increment a sleep count, we make sure
that we are the thread that will decrement the count when we wakeup.
Otherwise, what happens is that if we get interrupted (signal) and we
have to wake up, but before we get our mutex, some thread that wants
to wake us up detects that the count is non-zero and so enters wakeup_one(),
but there's nothing on the sleep queue and so we don't get woken up. The
thread will still decrement the sleep count, which is bad because we will
also decrement it again later (as we got interrupted) and are already off
the sleep queue.
2001-03-08 19:21:45 +00:00
David Malone
2239c07de9 Make the wait for sendfile buffers interruptable. Stops one process
consuming them all and then getting stuck.

Reviewed by:	dg
Reviewed by:	bmilekic
Observed by:	Andreas Persson <pap@garen.net>
2001-03-08 16:28:10 +00:00
John Baldwin
19eb87d22a Grab the process lock while calling psignal and before calling psignal. 2001-03-07 03:37:06 +00:00
Jonathan Lemon
2fd7d53d36 Return ECONNABORTED from accept if connection is closed while on the
listen queue, as well as the current behavior of a zero-length sockaddr.

Obtained from: KAME
Reviewed by: -net
2001-02-14 02:09:11 +00:00
Bosko Milekic
9ed346bab0 Change and clean the mutex lock interface.
mtx_enter(lock, type) becomes:

mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks)
mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized)

similarily, for releasing a lock, we now have:

mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN.
We change the caller interface for the two different types of locks
because the semantics are entirely different for each case, and this
makes it explicitly clear and, at the same time, it rids us of the
extra `type' argument.

The enter->lock and exit->unlock change has been made with the idea
that we're "locking data" and not "entering locked code" in mind.

Further, remove all additional "flags" previously passed to the
lock acquire/release routines with the exception of two:

MTX_QUIET and MTX_NOSWITCH

The functionality of these flags is preserved and they can be passed
to the lock/unlock routines by calling the corresponding wrappers:

mtx_{lock, unlock}_flags(lock, flag(s)) and
mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN
locks, respectively.

Re-inline some lock acq/rel code; in the sleep lock case, we only
inline the _obtain_lock()s in order to ensure that the inlined code
fits into a cache line. In the spin lock case, we inline recursion and
actually only perform a function call if we need to spin. This change
has been made with the idea that we generally tend to avoid spin locks
and that also the spin locks that we do have and are heavily used
(i.e. sched_lock) do recurse, and therefore in an effort to reduce
function call overhead for some architectures (such as alpha), we
inline recursion for this case.

Create a new malloc type for the witness code and retire from using
the M_DEV type. The new type is called M_WITNESS and is only declared
if WITNESS is enabled.

Begin cleaning up some machdep/mutex.h code - specifically updated the
"optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN
and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently
need those.

Finally, caught up to the interface changes in all sys code.

Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
Poul-Henning Kamp
1550c317bf Fix the <sys/queue.h> abuse.
Submitted by:	Dima Dorfman <dima@unixfreak.org>
Reviewed by:	/sbin/md5
2001-01-02 11:51:55 +00:00
Poul-Henning Kamp
7f9cb01893 Add an XXX about a <sys/queue.h> transgression which needs cleaned up. 2001-01-02 10:34:09 +00:00
Bosko Milekic
2a0c503e7a * Rename M_WAIT mbuf subsystem flag to M_TRYWAIT.
This is because calls with M_WAIT (now M_TRYWAIT) may not wait
  forever when nothing is available for allocation, and may end up
  returning NULL. Hopefully we now communicate more of the right thing
  to developers and make it very clear that it's necessary to check whether
  calls with M_(TRY)WAIT also resulted in a failed allocation.
  M_TRYWAIT basically means "try harder, block if necessary, but don't
  necessarily wait forever." The time spent blocking is tunable with
  the kern.ipc.mbuf_wait sysctl.
  M_WAIT is now deprecated but still defined for the next little while.

* Fix a typo in a comment in mbuf.h

* Fix some code that was actually passing the mbuf subsystem's M_WAIT to
  malloc(). Made it pass M_WAITOK instead. If we were ever to redefine the
  value of the M_WAIT flag, this could have became a big problem.
2000-12-21 21:44:31 +00:00
David Malone
7cc0979fd6 Convert more malloc+bzero to malloc+M_ZERO.
Submitted by:	josh@zipperup.org
Submitted by:	Robert Drehmel <robd@gmx.net>
2000-12-08 21:51:06 +00:00
David Greenman
8f9a5273a3 Changed second argument in a call to sf_buf_free() to be NULL instead of
PAGE_SIZE to match the prototype better. The argument is ignored, so this
is just to silence the compile-time warning.

Pointed out by:	jhb
2000-12-03 01:35:46 +00:00
Bosko Milekic
794cd879fe Make sure to free the sf_buf if we've allocated it but fail to allocate
an mbuf (ENOBUFS) before returning so that we don't leak sf_bufs in
the case where we're out of mbufs.

Submitted by: David Greenman (dg)
2000-12-02 00:40:57 +00:00
Matthew Dillon
279d722604 This patchset fixes a large number of file descriptor race conditions.
Pre-rfork code assumed inherent locking of a process's file descriptor
    array.  However, with the advent of rfork() the file descriptor table
    could be shared between processes.  This patch closes over a dozen
    serious race conditions related to one thread manipulating the table
    (e.g. closing or dup()ing a descriptor) while another is blocked in
    an open(), close(), fcntl(), read(), write(), etc...

PR: kern/11629
Discussed with: Alexander Viro <viro@math.psu.edu>
2000-11-18 21:01:04 +00:00
David Greenman
866746b6a6 Fixed a certain panic on IO error in sendfile(): Page must be set PG_BUSY
before calling vm_page_free() on it.
2000-11-12 14:51:15 +00:00
Bosko Milekic
e778918123 * Have m_pulldown() use the new M_WRITABLE() macro in order to determine
whether the given ext_buf is shared.

* Have the sf_bufs be setup with the mbuf subsystem using MEXTADD() with the
two new arguments.

Note: m_pulldown() is somewhat crotchy; the added comment explains the
situation.

Reviewed by: jlemon
2000-11-11 23:04:15 +00:00
Bosko Milekic
fe27eea9d1 Change the sf_bufs wakeups to be wakeup_one(), because we don't want to
wakeup all of the sleeping threads when we free only one buffer. This
avoids us having to needlessly try again (and fail, and go back to
sleep) for all the threads sleeping. We will now only wakeup the
thread we know will succeed.

Reviewed by: green
2000-11-04 21:55:25 +00:00
Bosko Milekic
0eecc42758 Setup and put to use the mutex lock for sf_freelist, the sendfile(2) bufs
freelist. Should now be thread-friendly, in part.

Note: More work is needed in uipc_syscalls.c, but it will have to wait until
the socket locking issues are at least 80% implemented and committed.
2000-11-04 07:16:08 +00:00
Boris Popov
9ff5ce6baf Add three new VOPs: VOP_CREATEVOBJECT, VOP_DESTROYVOBJECT and VOP_GETVOBJECT.
They will be used by nullfs and other stacked filesystems to support full
cache coherency.

Reviewed in general by:	mckusick, dillon
2000-09-12 09:49:08 +00:00
David Malone
a5c4836d39 Replace the mbuf external reference counting code with something
that should be better.

The old code counted references to mbuf clusters by using the offset
of the cluster from the start of memory allocated for mbufs and
clusters as an index into an array of chars, which did the reference
counting. If the external storage was not a cluster then reference
counting had to be done by the code using that external storage.

NetBSD's system of linked lists of mbufs was cosidered, but Alfred
felt it would have locking issues when the kernel was made more
SMP friendly.

The system implimented uses a pool of unions to track external
storage. The union contains an int for counting the references and
a pointer for forming a free list. The reference counts are
incremented and decremented atomically and so should be SMP friendly.
This system can track reference counts for any sort of external
storage.

Access to the reference counting stuff is now through macros defined
in mbuf.h, so it should be easier to make changes to the system in
the future.

The possibility of storing the reference count in one of the
referencing mbufs was considered, but was rejected 'cos it would
often leave extra mbufs allocated. Storing the reference count in
the cluster was also considered, but because the external storage
may not be a cluster this isn't an option.

The size of the pool of reference counters is available in the
stats provided by "netstat -m".

PR:		19866
Submitted by:	Bosko Milekic <bmilekic@dsuper.net>
Reviewed by:	alfred (glanced at by others on -net)
2000-08-19 08:32:59 +00:00
Brian Feldman
42ebfbf227 Modify ktrace's general I/O tracing, ktrgenio(), to use a struct uio *
instead of a struct iovec * array and int len.  Get rid of stupidly trying
to allocate all of the memory and copyin()ing the entire iovec[], and
instead just do the proper VOP_WRITE() in ktrwrite() using a copy of
the struct uio that the syscall originally used.

This solves the DoS which could easily be performed; to work around the
DoS, one could also remove "options KTRACE" from the kernel.  This is
a very strong MFC candidate for 4.1.

Found by:	art@OpenBSD.org
2000-07-02 08:08:09 +00:00
Alfred Perlstein
8757e5bbc5 unstatic getfp() so that other subsystems can use it.
make sendfile() use it.

Approved by: dg
2000-06-12 18:06:12 +00:00
Jake Burkholder
e39756439c Back out the previous change to the queue(3) interface.
It was not discussed and should probably not happen.

Requested by:		msmith and others
2000-05-26 02:09:24 +00:00
Jake Burkholder
740a1973a6 Change the way that the queue(3) structures are declared; don't assume that
the type argument to *_HEAD and *_ENTRY is a struct.

Suggested by:	phk
Reviewed by:	phk
Approved by:	mdodd
2000-05-23 20:41:01 +00:00
Jonathan Lemon
cb679c385e Introduce kqueue() and kevent(), a kernel event notification facility. 2000-04-16 18:53:38 +00:00
Brian Feldman
f48b807fc0 This is Bosko Milekic's mbuf allocation waiting code. Basically, this
means that running out of mbuf space isn't a panic anymore, and code
which runs out of network memory will sleep to wait for it.

Submitted by:	Bosko Milekic <bmilekic@dsuper.net>
Reviewed by:	green, wollman
1999-12-12 05:52:51 +00:00
Poul-Henning Kamp
9b962c56a4 General clean-up of socket.h and associated sources to synchronise up
with NetBSD and the Single Unix Specification v2.

This updates some structures with other, almost equivalent types and
effort is under way to get the whole more consistent.

Also removes a double definition of INET6 and some other clean-ups.

Reviewed by: green, bde, phk
Some part obtained from: NetBSD, SUSv2 specification
1999-11-24 20:49:04 +00:00
Poul-Henning Kamp
2e3c8fcbd0 This is a partial commit of the patch from PR 14914:
Alot of the code in sys/kern directly accesses the *Q_HEAD and *Q_ENTRY
   structures for list operations.  This patch makes all list operations
   in sys/kern use the queue(3) macros, rather than directly accessing the
   *Q_{HEAD,ENTRY} structures.

This batch of changes compile to the same object files.

Reviewed by:    phk
Submitted by:   Jake Burkholder <jake@checker.org>
PR:     14914
1999-11-16 10:56:05 +00:00
Poul-Henning Kamp
923502ff91 useracc() the prequel:
Merge the contents (less some trivial bordering the silly comments)
of <vm/vm_prot.h> and <vm/vm_inherit.h> into <vm/vm.h>.  This puts
the #defines for the vm_inherit_t and vm_prot_t types next to their
typedefs.

This paves the road for the commit to follow shortly: change
useracc() to use VM_PROT_{READ|WRITE} rather than B_{READ|WRITE}
as argument.
1999-10-29 18:09:36 +00:00
Brian Feldman
afce003453 Add a missing spl lowering.
Submitted by:	Ville-Pertti Keinonen <will@iki.fi>
1999-10-14 05:16:16 +00:00
Peter Wemm
d1f088dab5 Trim unused options (or #ifdef for undoc options).
Submitted by:	phk
1999-10-11 15:19:12 +00:00
Guido van Rooij
bdf7fdcb6f Plug a potential filedescriptor leak. This will probably almost
never be triggered.

Reviewed by:	 David Greenman
1999-09-30 19:13:17 +00:00
Brian Feldman
13ccadd4b0 This is what was "fdfix2.patch," a fix for fd sharing. It's pretty
far-reaching in fd-land, so you'll want to consult the code for
changes.  The biggest change is that now, you don't use
	fp->f_ops->fo_foo(fp, bar)
but instead
	fo_foo(fp, bar),
which increments and decrements the fp refcount upon entry and exit.
Two new calls, fhold() and fdrop(), are provided.  Each does what it
seems like it should, and if fdrop() brings the refcount to zero, the
fd is freed as well.

Thanks to peter ("to hell with it, it looks ok to me.") for his review.
Thanks to msmith for keeping me from putting locks everywhere :)

Reviewed by:	peter
1999-09-19 17:00:25 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Brian Feldman
e32c66c539 Fix fd race conditions (during shared fd table usage.) Badfileops is
now used in f_ops in place of NULL, and modifications to the files
are more carefully ordered. f_ops should also be set to &badfileops
upon "close" of a file.

This does not fix other problems mentioned in this PR than the first
one.

PR:		11629
Reviewed by:	peter
1999-08-04 18:53:50 +00:00
Matthew Dillon
d254af07a1 Fix warnings in preparation for adding -Wall -Wcast-qual to the
kernel compile
1999-01-27 21:50:00 +00:00
Bill Fenner
ec42cbfc24 Don't free the socket address if soaccept() / pru_accept() doesn't
return one.
1999-01-25 16:53:53 +00:00
Matthew Dillon
257aefa704 Addendum: The original code that the last commit 'fixed' actually did
not have a bug in it, but the last commit did make it more readable so
    we are keeping it.
1999-01-24 03:49:58 +00:00
Matthew Dillon
89600e8663 There was a situation where sendfile() might attempt to initiate I/O
on a PG_BUSY page, due to a bug in its sequencing of a conditional.
1999-01-24 01:15:58 +00:00
Matthew Dillon
0069f505eb Fixed a potential bug ( but maybe not ), where sendfile() clears PG_BUSY
on a page without testing for waiters.  Also collapsed busy wait into
    new vm_page_sleep_busy() inline ( see vm/vm_page.h )
1999-01-21 09:00:26 +00:00
Matthew Dillon
1c7c3c6a86 This is a rather large commit that encompasses the new swapper,
changes to the VM system to support the new swapper, VM bug
    fixes, several VM optimizations, and some additional revamping of the
    VM code.  The specific bug fixes will be documented with additional
    forced commits.  This commit is somewhat rough in regards to code
    cleanup issues.

Reviewed by:	"John S. Dyson" <root@dyson.iquest.net>, "David Greenman" <dg@root.com>
1999-01-21 08:29:12 +00:00
Archie Cobbs
f1d19042b0 The "easy" fixes for compiling the kernel -Wunused: remove unreferenced static
and local variables, goto labels, and functions declared but not defined.
1998-12-07 21:58:50 +00:00
David Greenman
911e8dbc2a Fixed broken code in sendfile(2) when using file offsets. 1998-12-03 12:35:47 +00:00
Don Lewis
9d2b090975 We can't call fsetown() from sonewconn() because sonewconn() is be called
from an interrupt context and fsetown() wants to peek at curproc, call
malloc(..., M_WAITOK), and fiddle with various unprotected data structures.
The fix is to move the code that duplicates the F_SETOWN/FIOSETOWN state
of the original socket to the new socket from sonewconn() to accept1(),
since accept1() runs in the correct context.  Deferring this until the
process calls accept() is harmless since the process can't do anything
useful with SIGIO on the new socket until it has the descriptor for that
socket.

One could make the case for not bothering to duplicate the
F_SETOWN/FIOSETOWN state and requiring the process to explicitly make the
fcntl() or ioctl() call on the new socket, but this would be incompatible
with the previous implementation and might break programs which rely on
the old semantics.

This bug was discovered by Andrew Gallatin <gallatin@cs.duke.edu>.
1998-11-23 00:45:39 +00:00
David Greenman
4f699173cb Closed a very narrow and rare race condition that involved net interrupts,
bio interrupts, and a truncated file that along with the precise alignment
of the planets could result in a page being freed multiple times or a
just-freed page being put onto the inactive queue.
1998-11-18 09:00:47 +00:00