Commit Graph

103 Commits

Author SHA1 Message Date
Ralf Baechle 367f0b50e5 MIPS: Wire up renameat2 syscall.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-13 17:57:33 +02:00
Markos Chandras 4c21b8fd8f MIPS: seccomp: Handle indirect system calls (o32)
When userland uses syscall() to perform an indirect system call
the actually system call that needs to be checked by the filter
is on the first argument. The kernel code needs to handle this case
by looking at the original syscall number in v0 and if it's
NR_syscall, then it needs to examine the first argument to
identify the real system call that will be executed.
Similarly, we need to 'virtually' shift the syscall() arguments
so the syscall_get_arguments() function can fetch the correct
arguments for the indirect system call.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6404/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-03-26 23:09:08 +01:00
Markos Chandras 9d37c405ed MIPS: kernel: scalls: Skip the syscall if denied by the seccomp filter
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6399/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-03-26 23:09:08 +01:00
James Hogan 6776254b1c MIPS: Wire up sched_setattr/sched_getattr syscalls
Wire up for MIPS the new sched_setattr and sched_getattr system calls
added in commit d50dde5a10 (sched: Add new scheduler syscalls to
support an extended scheduling parameters ABI) merged in v3.14-rc1.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6502/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-02-04 13:47:46 +01:00
Ralf Baechle 2a9c275176 MIPS: compat: Export O32 syscall table and rename to avoid duplicate symbol.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-10-29 21:24:52 +01:00
Ralf Baechle e7f3b48af7 MIPS: Cleanup flags in syscall flags handlers.
This will simplify further modifications.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-10 18:01:26 +02:00
Al Viro 91c2e0bcae unify compat fanotify_mark(2), switch to COMPAT_SYSCALL_DEFINE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-09 13:46:38 -04:00
Al Viro 56e41d3c5a merge compat sys_ipc instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-03 23:00:27 -05:00
Al Viro d5dc77bfee consolidate compat lookup_dcookie()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-03 23:00:23 -05:00
Al Viro 19f4fc3aee convert sendfile{,64} to COMPAT_SYSCALL_DEFINE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-03 22:58:46 -05:00
Linus Torvalds 14cc0b55b7 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull signal/compat fixes from Al Viro:
 "Fixes for several regressions introduced in the last signal.git pile,
  along with fixing bugs in truncate and ftruncate compat (on just about
  anything biarch at least one of those two had been done wrong)."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  compat: restore timerfd settime and gettime compat syscalls
  [regression] braino in "sparc: convert to ksignal"
  fix compat truncate/ftruncate
  switch lseek to COMPAT_SYSCALL_DEFINE
  lseek() and truncate() on sparc really need sign extension
2013-03-02 08:34:06 -08:00
Linus Torvalds aebb2afd54 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:

 o Add basic support for the Mediatek/Ralink Wireless SoC family.

 o The Qualcomm Atheros platform is extended by support for the new
   QCA955X SoC series as well as a bunch of patches that get the code
   ready for OF support.

 o Lantiq and BCM47XX platform have a few improvements and bug fixes.

 o MIPS has sent a few patches that get the kernel ready for the
   upcoming microMIPS support.

 o The rest of the series is made up of small bug fixes and cleanups
   that relate to various parts of the MIPS code.  The biggy in there is
   a whitespace cleanup.  After I was sent another set of whitespace
   cleanup patches I decided it was the time to clean the whitespace
   "issues" for once and and that touches many files below arch/mips/.

Fix up silly conflicts, mostly due to whitespace cleanups.

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (105 commits)
  MIPS: Quit exporting kernel internel break codes to uapi/asm/break.h
  MIPS: remove broken conditional inside vpe loader code
  MIPS: SMTC: fix implicit declaration of set_vi_handler
  MIPS: early_printk: drop __init annotations
  MIPS: Probe for and report hardware virtualization support.
  MIPS: ath79: add support for the Qualcomm Atheros AP136-010 board
  MIPS: ath79: add USB controller registration code for the QCA955X SoCs
  MIPS: ath79: add PCI controller registration code for the QCA955X SoCs
  MIPS: ath79: add WMAC registration code for the QCA955X SoCs
  MIPS: ath79: register UART for the QCA955X SoCs
  MIPS: ath79: add QCA955X specific glue to ath79_device_reset_{set, clear}
  MIPS: ath79: add GPIO setup code for the QCA955X SoCs
  MIPS: ath79: add IRQ handling code for the QCA955X SoCs
  MIPS: ath79: add clock setup code for the QCA955X SoCs
  MIPS: ath79: add SoC detection code for the QCA955X SoCs
  MIPS: ath79: add early printk support for the QCA955X SoCs
  MIPS: ath79: fix WMAC IRQ resource assignment
  mips: reserve elfcorehdr
  mips: Make sure kernel memory is in iomem
  MIPS: ath79: use dynamically allocated USB platform devices
  ...
2013-03-02 07:44:16 -08:00
Al Viro 3f6d078d4a fix compat truncate/ftruncate
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-25 09:24:55 -05:00
Al Viro 50150d2bb9 mips: switch to generic sys_fork() and sys_clone()
we still need the wrappers to store callee-saved registers in
pt_regs, but once that done we can jump to kernel/fork.c variants.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 18:33:02 -05:00
Al Viro 5e392b8db7 mips: don't bother with compat_sys_futex() wrappers
... it's COMPAT_SYSCALL_DEFINE now

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 18:33:01 -05:00
Al Viro aa584802e5 mips: switch to generic compat rt_sigaction()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 18:33:00 -05:00
Al Viro 0450d22f4b mips: switch to generic compat sched_rr_get_interval()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 18:33:00 -05:00
Al Viro ea5d83db67 mips: switch to generic compat rt_sigqueueinfo()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 18:32:59 -05:00
Al Viro 45cb66f797 mips: switch to generic compat rt_sigpending()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 18:32:59 -05:00
Al Viro 056a060803 mips: switch to generic compat rt_sigprocmask()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 18:32:58 -05:00
Al Viro bde208d2e1 switch mips to generic rt_sigsuspend(), make it unconditional
mips was the last architecture not using the generic variant.
Both native and compat variants switched to generic, which is
made unconditional now.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 18:32:49 -05:00
Al Viro 1c37ea8277 mips: switch to compat_sys_waitid()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 18:32:24 -05:00
Al Viro ea536ad4f2 mips: switch to generic sigaltstack
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 18:32:24 -05:00
Ralf Baechle 7034228792 MIPS: Whitespace cleanup.
Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-02-01 10:00:22 +01:00
Ralf Baechle 6295150b73 MIPS: Wire up finit_module syscall.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-12-28 17:04:38 +01:00
Ralf Baechle baf9ff74ed MIPS: Switch over to generic sys_execve and kernel_execve.
This version contains a few updates by David Daney, in particular it's
now using __builtin_frame_address() instead of asm() which depending
on personal taste, is slightly more appealing.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-10-14 19:31:30 -04:00
Ralf Baechle ce71d24cff MIPS: Wire kcmp syscall.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-09-26 11:24:28 +02:00
Al Viro 02f884ed46 MIPS: Merge the identical "return from syscall" per-ABI code
No need to keep 4 copies of that stuff; merged and taken to
entry.S, unused public symbols there killed off.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-09-22 15:47:31 +02:00
David Daney 8ff8584e51 MIPS: Hook up process_vm_readv and process_vm_writev system calls.
Signed-off-by: David Daney <david.daney@cavium.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2918/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-11-09 00:07:56 +00:00
Yong Zhang 1eec6cd08b MIPS: Compat: Use 32-bit wrapper for compat_sys_futex.
We can't trust userspace to pass signed-extend arguments.  Not correctly
sign-extended arguments to futex-wait result in architecturally undefined
operation of 32-bit arithmetic instructions.

For example, if 'val' is too big and bit-31 is 1, the caller may enter
endless loop at:

futex_wait_setup()
{
	...

	if (uval != val) {
		queue_unlock(q, *hb);
		ret = -EWOULDBLOCK;

	...
}

Signed-off-by: Yong Zhang <yong.zhang@windriver.com>
To: linux-mips@linux-mips.org
To: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/2714/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-09-21 17:53:44 +02:00
NeilBrown f5b9409973 All Arch: remove linkage for sys_nfsservctl system call
The nfsservctl system call is now gone, so we should remove all
linkage for it.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-26 15:09:58 -07:00
Ralf Baechle b12acf163f MIPS: Wire up sendmmsg and renumber setns syscall.
Renumbering was necessary because I had already wired up setns(2) in the
linux-mips.org tree in commit c3fce54644cabbb90700cc3acc040718a377f609
[MIPS: Wire up new sendmmsg syscall.] but the same syscall numbers were
used by 7b21fddd08 [ns: Wire up the setns
system call] resulting in a conflict.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-07-20 23:12:10 +01:00
Eric W. Biederman 7b21fddd08 ns: Wire up the setns system call
32bit and 64bit on x86 are tested and working.  The rest I have looked
at closely and I can't find any problems.

setns is an easy system call to wire up.  It just takes two ints so I
don't expect any weird architecture porting problems.

While doing this I have noticed that we have some architectures that are
very slow to get new system calls.  cris seems to be the slowest where
the last system calls wired up were preadv and pwritev.  avr32 is weird
in that recvmmsg was wired up but never declared in unistd.h.  frv is
behind with perf_event_open being the last syscall wired up.  On h8300
the last system call wired up was epoll_wait.  On m32r the last system
call wired up was fallocate.  mn10300 has recvmmsg as the last system
call wired up.  The rest seem to at least have syncfs wired up which was
new in the 2.6.39.

v2: Most of the architecture support added by Daniel Lezcano <dlezcano@fr.ibm.com>
v3: ported to v2.6.36-rc4 by: Eric W. Biederman <ebiederm@xmission.com>
v4: Moved wiring up of the system call to another patch
v5: ported to v2.6.39-rc6
v6: rebased onto parisc-next and net-next to avoid syscall  conflicts.
v7: ported to Linus's latest post 2.6.39 tree.

>  arch/blackfin/include/asm/unistd.h     |    3 ++-
>  arch/blackfin/mach-common/entry.S      |    1 +
Acked-by: Mike Frysinger <vapier@gentoo.org>

Oh - ia64 wiring looks good.
Acked-by: Tony Luck <tony.luck@intel.com>

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-28 10:48:39 -07:00
Ralf Baechle 8b659a3931 MIPS: Split do_syscall_trace into two functions.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-05-19 09:55:44 +01:00
Ralf Baechle 8bdd51429d MIPS: Document former use of timerfd(2) syscall number.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-05-10 18:15:25 +01:00
Ralf Baechle 1bbf287561 MIPS: Wire up syncfs(2).
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-03-25 18:45:20 +01:00
David Daney 84ed94323e MIPS: Hook up name_to_handle_at, open_by_handle_at and clock_adjtime syscalls.
These system calls we recently added.

32-bit ABIs need compat handling for sys_clock_adjtime().

o32 also needs compat handling for sys_open_by_handle_at();

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2165/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-03-25 18:45:20 +01:00
Linus Torvalds 7d7c4d06be Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus:
  MIPS: O32 compat/N32: Fix to use compat syscall wrappers for AIO syscalls.
  MAINTAINERS: Change list for ioc_serial to linux-serial.
  SERIAL: ioc3_serial: Return -ENOMEM on memory allocation failure
  MIPS: jz4740: Fix Kbuild Platform file.
  MIPS: Repair Kbuild make clean breakage.
2010-10-20 13:18:21 -07:00
Michel Thebeau e2cc502c3f MIPS: O32 compat/N32: Fix to use compat syscall wrappers for AIO syscalls.
[Ralf: Michel's original patch only fixed N32; I replicated the same fix
for O32.]

Signed-off-by: Michel Thebeau <michel.thebeau@windriver.com>
Cc: paul.gortmaker@windriver.com
Cc: bruce.ashfield@windriver.com
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-10-19 18:32:41 +01:00
Linus Torvalds 547af560dd Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus:
  MIPS: Enable ISA_DMA_API config to fix build failure
  MIPS: 32-bit: Fix build failure in asm/fcntl.h
  MIPS: Remove all generated vmlinuz* files on "make clean"
  MIPS: do_sigaltstack() expects userland pointers
  MIPS: Fix error values in case of bad_stack
  MIPS: Sanitize restart logics
  MIPS: secure_computing, syscall audit: syscall number should in r2, not r0.
  MIPS: Don't block signals if we'd failed to setup a sigframe
2010-10-18 13:10:36 -07:00
Al Viro 5b89c0044e MIPS: Fix error values in case of bad_stack
We want EFAULT, not -<syscall number>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-kernel@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1699/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-10-18 16:59:03 +01:00
Al Viro 8f5a00eb42 MIPS: Sanitize restart logics
Put the original syscall number into ->regs[0] when we leave syscall
with error.  Use it in restart logics.  Everything else will have
it 0 since we pass through SAVE_SOME on all the ways in.  Note that
in places like bad_stack and inllegal_syscall we leave it 0 - it's not
restartable.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-kernel@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1698/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-10-18 16:59:02 +01:00
David Daney 5e844b31c2 MIPS: Hookup fanotify_init, fanotify_mark, and prlimit64 syscalls.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1553/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-10-04 18:33:59 +01:00
Christoph Hellwig e28cbf2293 improve sys_newuname() for compat architectures
On an architecture that supports 32-bit compat we need to override the
reported machine in uname with the 32-bit value.  Instead of doing this
separately in every architecture introduce a COMPAT_UTS_MACHINE define in
<asm/compat.h> and apply it directly in sys_newuname().

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:32 -08:00
Linus Torvalds d7fc02c7ba Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1815 commits)
  mac80211: fix reorder buffer release
  iwmc3200wifi: Enable wimax core through module parameter
  iwmc3200wifi: Add wifi-wimax coexistence mode as a module parameter
  iwmc3200wifi: Coex table command does not expect a response
  iwmc3200wifi: Update wiwi priority table
  iwlwifi: driver version track kernel version
  iwlwifi: indicate uCode type when fail dump error/event log
  iwl3945: remove duplicated event logging code
  b43: fix two warnings
  ipw2100: fix rebooting hang with driver loaded
  cfg80211: indent regulatory messages with spaces
  iwmc3200wifi: fix NULL pointer dereference in pmkid update
  mac80211: Fix TX status reporting for injected data frames
  ath9k: enable 2GHz band only if the device supports it
  airo: Fix integer overflow warning
  rt2x00: Fix padding bug on L2PAD devices.
  WE: Fix set events not propagated
  b43legacy: avoid PPC fault during resume
  b43: avoid PPC fault during resume
  tcp: fix a timewait refcnt race
  ...

Fix up conflicts due to sysctl cleanups (dead sysctl_check code and
CTL_UNNUMBERED removed) in
	kernel/sysctl_check.c
	net/ipv4/sysctl_net_ipv4.c
	net/ipv6/addrconf.c
	net/sctp/sysctl.c
2009-12-08 07:55:01 -08:00
David S. Miller 3505d1a9fd Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/sfc/sfe4001.c
	drivers/net/wireless/libertas/cmd.c
	drivers/staging/Kconfig
	drivers/staging/Makefile
	drivers/staging/rtl8187se/Kconfig
	drivers/staging/rtl8192e/Kconfig
2009-11-18 22:19:03 -08:00
Eric W. Biederman aff639cdcf sysctl: mips Use the compat_sys_sysctl
Now that we have a generic 32bit compatibility implementation
there is no need for mips to implement it's own.

Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2009-11-06 03:53:18 -08:00
Arnaud Patard 049a31afe1 MIPS: O32: Fix ppoll
sys_ppoll syscall needs to use a compat handler on 64bit kernels with o32
user-space.

Signed-off-by: Arnaud Patard <apatard@mandriva.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-11-02 12:00:08 +01:00
Wu Zhangjin 80b8585b07 MIPS: 64-bit: Fix o32 lookup_dcookie syscall
An o32 aplication passes a 64-bit value in a pair of registers; a 64-bit
kernel expects a 64-bit argument in a single register.

Signed-off-by: Chen Jie <chenj@lemote.com>
Signed-off-by: Hu Hongbing <huhb@lemote.com>
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-11-02 12:00:02 +01:00
Arnaldo Carvalho de Melo a2e2725541 net: Introduce recvmmsg socket syscall
Meaning receive multiple messages, reducing the number of syscalls and
net stack entry/exit operations.

Next patches will introduce mechanisms where protocols that want to
optimize this operation will provide an unlocked_recvmsg operation.

This takes into account comments made by:

. Paul Moore: sock_recvmsg is called only for the first datagram,
  sock_recvmsg_nosec is used for the rest.

. Caitlin Bestler: recvmmsg now has a struct timespec timeout, that
  works in the same fashion as the ppoll one.

  If the underlying protocol returns a datagram with MSG_OOB set, this
  will make recvmmsg return right away with as many datagrams (+ the OOB
  one) it has received so far.

. Rémi Denis-Courmont & Steven Whitehouse: If we receive N < vlen
  datagrams and then recvmsg returns an error, recvmmsg will return
  the successfully received datagrams, store the error and return it
  in the next call.

This paves the way for a subsequent optimization, sk_prot->unlocked_recvmsg,
where we will be able to acquire the lock only at batch start and end, not at
every underlying recvmsg call.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-12 23:40:10 -07:00