I've finally found a potential cause of the sk_forward_alloc underflows
that people have been reporting sporadically.
When tcp_sendmsg tacks on extra bits to an existing TCP_PAGE we don't
check sk_forward_alloc even though a large amount of time may have
elapsed since we allocated the page. In the mean time someone could've
come along and liberated packets and reclaimed sk_forward_alloc memory.
This patch makes tcp_sendmsg check sk_forward_alloc every time as we
do in do_tcp_sendpages.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces sk_stream_wmem_schedule as a short-hand for
the sk_forward_alloc checking on egress.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The crypto layer currently uses in_atomic() to determine whether it is
allowed to sleep. This is incorrect since spin locks don't always cause
in_atomic() to return true.
Instead of that, this patch returns to an earlier idea of a per-tfm flag
which determines whether sleeping is allowed. Unlike the earlier version,
the default is to not allow sleeping. This ensures that no existing code
can break.
As usual, this flag may either be set through crypto_alloc_tfm(), or
just before a specific crypto operation.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently tun/tap only supports the EN10MB ARP type. For use with
wireless and other networking types it should be possible to set the
ARP type via an ioctl.
Patch v2: Included check that the tap interface is down before changing the
link type out from underneath it
Signed-off-by: Mike Kershaw <dragorn@kismetwireless.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Patch from Nicolas Pitre
The prototype for sys_fadvise64_64() is:
long sys_fadvise64_64(int fd, loff_t offset, loff_t len, int advice)
The argument list is therefore as follows on legacy ABI:
fd: type int (r0)
offset: type long long (r1-r2)
len: type long long (r3-sp[0])
advice: type int (sp[4])
With EABI this becomes:
fd: type int (r0)
offset: type long long (r2-r3)
len: type long long (sp[0]-sp[4])
advice: type int (sp[8])
Not only do we have ABI differences here, but the EABI version requires
one additional word on the syscall stack.
To avoid the ABI mismatch and the extra stack space required with EABI
this syscall is now defined with a different argument ordering
on ARM as follows:
long sys_arm_fadvise64_64(int fd, int advice, loff_t offset, loff_t len)
This gives us the following ABI independent argument distribution:
fd: type int (r0)
advice: type int (r1)
offset: type long long (r2-r3)
len: type long long (sp[0]-sp[4])
Now, since the syscall entry code takes care of 5 registers only by
default including the store of r4 to the stack, we need a wrapper to
store r5 to the stack as well. Because that wrapper was missing and was
always required this means that sys_fadvise64_64 never worked on ARM and
therefore we can safely reuse its syscall number for our new
sys_arm_fadvise64_64 interface.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This kills warnings when building drivers/ide/ide-iops.c
and puts us in-line with what other platforms do here.
Signed-off-by: David S. Miller <davem@davemloft.net>
Patch from Sascha Hauer
This patch adds support for setting and getting RTS / CTS via
set_mtctrl / get_mctrl functions.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from David Vrabel
Correct the ioread* and iowrite* functions. In particular, add an offset to the cookie in ioport_map so we can map I/O port ranges starting from 0 (0 is for reporting errors).
Signed-off-by: David Vrabel <dvrabel@arcom.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
- notifying the PROM of specific features that are supported by the OS.
This is used to enable PROM feature if and only if the corresponding
feature is implemented in the OS
- fetch feature sets that are supported by the current PROM. This allows
the OS to selectively enable features when the PROM support is available.
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The start_tx and stop_tx methods were passed a flag to indicate
whether the start/stop was from the tty start/stop callbacks, and
some drivers used this flag to decide whether to ask the UART to
immediately stop transmission (where the UART supports such a
feature.)
There are other cases when we wish this to occur - when CTS is
lowered, or if we change from soft to hard flow control and CTS
is inactive. In these cases, this flag was false, and we would
allow the transmitter to drain before stopping.
There is really only one case where we want to let the transmitter
drain before disabling, and that's when we run out of characters
to send.
Hence, re-jig the start_tx and stop_tx methods to eliminate this
flag, and introduce new functions for the special "disable and
allow transmitter to drain" case.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The idea behind a RAID class is to provide a uniform interface to all
RAID subsystems (both hardware and software) in the kernel.
To do that, I've made this class a transport class that's entirely
subsystem independent (although the matching routines have to match per
subsystem, as you'll see looking at the code). I put it in the scsi
subdirectory purely because I needed somewhere to play with it, but it's
not a scsi specific module.
I used a fusion raid card as the test bed for this; with that kind of
card, this is the type of class output you get:
jejb@titanic> ls -l /sys/class/raid_devices/20\:0\:0\:0/
total 0
lrwxrwxrwx 1 root root 0 Aug 16 17:21 component-0 -> ../../../devices/pci0000:80/0000:80:04.0/host20/target20:1:0/20:1:0:0/
lrwxrwxrwx 1 root root 0 Aug 16 17:21 component-1 -> ../../../devices/pci0000:80/0000:80:04.0/host20/target20:1:1/20:1:1:0/
lrwxrwxrwx 1 root root 0 Aug 16 17:21 device -> ../../../devices/pci0000:80/0000:80:04.0/host20/target20:0:0/20:0:0:0/
-r--r--r-- 1 root root 16384 Aug 16 17:21 level
-r--r--r-- 1 root root 16384 Aug 16 17:21 resync
-r--r--r-- 1 root root 16384 Aug 16 17:21 state
So it's really simple: for a SCSI device representing a hardware raid,
it shows the raid level, the array state, the resync % complete (if the
state is resyncing) and the underlying components of the RAID (these are
exposed in fusion on the virtual channel 1).
As you can see, this type of information can be exported by almost
anything, including software raid.
The more difficult trick, of course, is going to be getting it to
perform configuration type actions with writable attributes.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
One of the changes in the attribute_container code in the scsi-misc tree
was to add a lock to protect the list of devices per container. This,
unfortunately, leads to potential scheduling while atomic problems if
there's a sleep in the function called by a trigger.
The correct solution is to use the kernel klist infrastructure instead
which allows lockless traversal of a list.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Peter Staubach pointed out that it is not correct to check
current->personality & PER_LINUX32 (this will have false
hits on several other personality values).
Signed-off-by: Tony Luck <tony.luck@intel.com>
