than one active reference to a file descriptor. It should dislodge threads
sleeping while holding a reference to the descriptor. Implemented only for
sockets but should be extended to pipes, fifos, etc.
Fixes the case of a multithreaded process doing something like the
following, which would have hung until the process got a signal.
thr0 accept(fd, ...)
thr1 close(fd)
- Socket layer becomes MP safe.
- Unix protocols become MP safe.
- Allows protocol processing interrupts to safely block on locks.
- Fixes a number of race conditions.
With much feedback from matt@ and plunky@.
This is for netsmb which wants to poll sockets directly.
- When polling a socket, first check for pending I/O without acquring any
locks. If no I/O seems to be pending, acquire locks/spl and check again
doing selrecord() if necessary.
- use vmspace rather than proc or lwp where appropriate.
the latter is more natural to specify an address space.
(and less likely to be abused for random purposes.)
- fix a swdmover race.
the number of bytes in the send queue, and FIONSPACE reports the
number of free bytes in the send queue. These ioctls permit applications
to monitor file descriptor transmission dynamics.
In examining prior art, FIONWRITE exists with the semantics given
here. FIONSPACE is provided so that programs may easily determine how
much space is left in the send queue; they do not need to know the
send queue size.
The fact that a write may block even if there is enough space in the
send queue for it is noted in the documentation.
FIONWRITE functionality may be used to implement TIOCOUTQ for Linux
emulation - Linux extended this ioctl to sockets, even though they are
not ttys.
Add a new explicit `struct proc *p' argument to socreate(), sosend().
Use that argument instead of curproc. Follow-on changes to pass that
argument to socreate(), sosend(), and (*so->so_send)() calls.
These changes reviewed and independently recoded by Matt Thomas.
Changes to soreceive() and (*dom->dom_exernalize() from Matt Thomas:
pass soreceive()'s struct uio* uio->uio_procp to unp_externalize().
Eliminate curproc from unp_externalize. Also, now soreceive() uses
its uio->uio_procp value, pass that same value downward to
((pr->pru_usrreq)() calls for consistency, instead of (struct proc * )0.
Similar changes in sys/nfs to eliminate (most) uses of curproc,
either via the req-> r_procp field of a struct nfsreq *req argument,
or by passing down new explicit struct proc * arguments.
Reviewed by: Matt Thomas, posted to tech-kern.
NB: The (*pr->pru_usrreq)() change should be tested on more (all!) protocols.
* introduce fsetown(), fgetown(), fownsignal() - this sets/retrieves/signals
the owner of descriptor, according to appropriate sematics
of TIOCSPGRP/FIOSETOWN/SIOCSPGRP/TIOCGPGRP/FIOGETOWN/SIOCGPGRP ioctl; use
these routines instead of custom code where appropriate
* make every place handling TIOCSPGRP/TIOCGPGRP handle also FIOSETOWN/FIOGETOWN
properly, and remove the translation of FIO[SG]OWN to TIOC[SG]PGRP
in sys_ioctl() & sys_fcntl()
* also remove the socket-specific hack in sys_ioctl()/sys_fcntl() and
pass the ioctls down to soo_ioctl() as any other ioctl
change discussed on tech-kern@
be inserted into ktrace records. The general change has been to replace
"struct proc *" with "struct lwp *" in various function prototypes, pass
the lwp through and use l_proc to get the process pointer when needed.
Bump the kernel rev up to 1.6V
Avoids a lot of casting and removes the need for some line breaks.
Removed a load of (caddr_t) casts from calls to copyin/copyout as well.
(approved by christos - he has a plan to remove caddr_t...)
kqueue provides a stateful and efficient event notification framework
currently supported events include socket, file, directory, fifo,
pipe, tty and device changes, and monitoring of processes and signals
kqueue is supported by all writable filesystems in NetBSD tree
(with exception of Coda) and all device drivers supporting poll(2)
based on work done by Jonathan Lemon for FreeBSD
initial NetBSD port done by Luke Mewburn and Jason Thorpe
struct socket so_state field to decide if we need to send asynchronous
notifications. This makes possible to request notification on write but
not on read, and vice versa.
This is used in Linux emulation code, because when async I/O is requested,
Linux does not send SIGIO to write end of sockets, and it never send any
SIGIO to any end of pipes. Il Linux emulation code, we then set SB_ASYNC
only on the read end of sockets, and on no end for pipes.
flag.
EMUL_BSD_ASYNCIO_PIPE notes that the emulated binaries expect the original
BSD pipe behavior for asynchronous I/O, which is to fire SIGIO on read() and
write(). OSes without this flag do not expect any SIGIO to be fired on
read() and write() for pipes, even when async I/O was requested. As far as
we know, the OSes that need EMUL_BSD_ASYNCIO_PIPE are NetBSD, OSF/1 and
Darwin.
callers and appropriate routines to cope. This makes fo_stat more
consistent with rest of fileops routines and also makes the fo_stat
match FreeBSD as an added bonus.
Discussed with Luke Mewburn on tech-kern@.
call with F_FSCTL set and F_SETFL calls generate calls to a new
fileop fo_fcntl. Add genfs_fcntl() and soo_fcntl() which return 0
for F_SETFL and EOPNOTSUPP otherwise. Have all leaf filesystems
use genfs_fcntl().
Reviewed by: thorpej
Tested by: wrstuden
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