Commit Graph

68 Commits

Author SHA1 Message Date
Jiri Slaby 1977f03272 remove asm/bitops.h includes
remove asm/bitops.h includes

including asm/bitops directly may cause compile errors. don't include it
and include linux/bitops instead. next patch will deny including asm header
directly.

Cc: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:41 -07:00
Al Viro d9a19d200f hamradio: ->hard_header() takes packet type in host-endian
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-14 12:41:52 -07:00
Stephen Hemminger 3b04ddde02 [NET]: Move hardware header operations out of netdevice.
Since hardware header operations are part of the protocol class
not the device instance, make them into a separate object and
save memory.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:52:52 -07:00
Stephen Hemminger 0c4e85813d [NET]: Wrap netdevice hardware header creation.
Add inline for common usage of hardware header creation, and
fix bug in IPV6 mcast where the assumption about negative return is
an errno. Negative return from hard_header means not enough space
was available,(ie -N bytes).

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:52:50 -07:00
Joe Perches 0795af5729 [NET]: Introduce and use print_mac() and DECLARE_MAC_BUF()
This is nicer than the MAC_FMT stuff.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:51:42 -07:00
Ralf Baechle 10d024c1b2 [NET]: Nuke SET_MODULE_OWNER macro.
It's been a useless no-op for long enough in 2.6 so I figured it's time to
remove it.  The number of people that could object because they're
maintaining unified 2.4 and 2.6 drivers is probably rather small.

[ Handled drivers added by netdev tree and some missed IRDA cases... -DaveM ]

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:51:13 -07:00
Eric W. Biederman e9dc865340 [NET]: Make device event notification network namespace safe
Every user of the network device notifiers is either a protocol
stack or a pseudo device.  If a protocol stack that does not have
support for multiple network namespaces receives an event for a
device that is not in the initial network namespace it quite possibly
can get confused and do the wrong thing.

To avoid problems until all of the protocol stacks are converted
this patch modifies all netdev event handlers to ignore events on
devices that are not in the initial network namespace.

As the rest of the code is made network namespace aware these
checks can be removed.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:09 -07:00
Eric W. Biederman e730c15519 [NET]: Make packet reception network namespace safe
This patch modifies every packet receive function
registered with dev_add_pack() to drop packets if they
are not from the initial network namespace.

This should ensure that the various network stacks do
not receive packets in a anything but the initial network
namespace until the code has been converted and is ready
for them.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:08 -07:00
Eric W. Biederman 457c4cbc5a [NET]: Make /proc/net per network namespace
This patch makes /proc/net per network namespace.  It modifies the global
variables proc_net and proc_net_stat to be per network namespace.
The proc_net file helpers are modified to take a network namespace argument,
and all of their callers are fixed to pass &init_net for that argument.
This ensures that all of the /proc/net files are only visible and
usable in the initial network namespace until the code behind them
has been updated to be handle multiple network namespaces.

Making /proc/net per namespace is necessary as at least some files
in /proc/net depend upon the set of network devices which is per
network namespace, and even more files in /proc/net have contents
that are relevant to a single network namespace.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:06 -07:00
Paul E. McKenney b34bd06e48 bpqether: fix rcu usage
The rcu_dereference() primitive needs to be applied to an l-value in order to
ensure that compiler writers don't get an opportunity to apply reordering
optimizations that could result in multiple fetches or in other misbehavior.
This patch pulls the rcu_dereference() calls in bpq_seq_next() up to the point
at which the fetched pointers are still l-values, rather than after
list_entry() has transformed them into r-values.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-31 15:39:40 -07:00
Yoann Padioleau dd00cc486a some kmalloc/memset ->kzalloc (tree wide)
Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc).

Here is a short excerpt of the semantic patch performing
this transformation:

@@
type T2;
expression x;
identifier f,fld;
expression E;
expression E1,E2;
expression e1,e2,e3,y;
statement S;
@@

 x =
- kmalloc
+ kzalloc
  (E1,E2)
  ...  when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\)
- memset((T2)x,0,E1);

@@
expression E1,E2,E3;
@@

- kzalloc(E1 * E2,E3)
+ kcalloc(E1,E2,E3)

[akpm@linux-foundation.org: get kcalloc args the right way around]
Signed-off-by: Yoann Padioleau <padator@wanadoo.fr>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Bryan Wu <bryan.wu@analog.com>
Acked-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Acked-by: Roland Dreier <rolandd@cisco.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Acked-by: Pierre Ossman <drzeus-list@drzeus.cx>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Greg KH <greg@kroah.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:50 -07:00
Jeremy Fitzhardinge 86313c488a usermodehelper: Tidy up waiting
Rather than using a tri-state integer for the wait flag in
call_usermodehelper_exec, define a proper enum, and use that.  I've
preserved the integer values so that any callers I've missed should
still work OK.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: David Howells <dhowells@redhat.com>
2007-07-18 08:47:40 -07:00
Robert P. J. Day 1591275cb5 Fix "deprecated" typoes.
Fix remaining misspellings of "depreciated" to "deprecated."

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2007-05-09 07:18:01 +02:00
Folkert van Heusden 939456ac51 baycom_ser_fdx: also allow i/o ports >= 0x1000 and enhanced failure logging
The baycom_ser_fdx driver did not allow i/o ports >= 0x1000.  Now that
there are pci cards (with rs232 ports) which use for example 0xb800 this
limit should not exists.

Also, for non kernel coders find the cause of problems was challenging so I
added extra logging.

Signed-off-by: Folkert van Heusden <folkert@vanheusden.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-04-28 11:01:02 -04:00
Andrew Morton 55404bca6c [NET]: Fix yam.c
drivers/net/hamradio/yam.c: In function `yam_tx_byte':
drivers/net/hamradio/yam.c:643: warning: passing arg 1 of `skb_copy_from_linear_data_offset' from incompatible pointer type

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 00:55:53 -07:00
Arnaldo Carvalho de Melo d626f62b11 [SK_BUFF]: Introduce skb_copy_from_linear_data{_offset}
To clearly state the intent of copying from linear sk_buffs, _offset being a
overly long variant but interesting for the sake of saving some bytes.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2007-04-25 22:28:23 -07:00
Arnaldo Carvalho de Melo c1d2bbe1cd [SK_BUFF]: Introduce skb_reset_network_header(skb)
For the common, open coded 'skb->nh.raw = skb->data' operation, so that we can
later turn skb->nh.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple case, next will handle the slightly more
"complex" cases.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:46 -07:00
Andrew Morton 5efb764c86 drivers/net/hamradio/baycom_ser_fdx build fix
sparc64:

drivers/net/hamradio/baycom_ser_fdx.c: In function `ser12_open':
drivers/net/hamradio/baycom_ser_fdx.c:417: error: `NR_IRQS' undeclared (first us
e in this function)
drivers/net/hamradio/baycom_ser_fdx.c:417: error: (Each undeclared identifier is
 reported only once
drivers/net/hamradio/baycom_ser_fdx.c:417: error: for each function it appears i
n.)

Cc: Folkert van Heusden <folkert@vanheusden.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-04-24 12:51:03 -04:00
Ralf Baechle 8b5b467181 Replace local random function with random32()
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-20 11:18:13 -05:00
Simon Depiets 6486abbf63 fix the BAYCOM_SER_HDX help text
This fixes kernel Bugzilla #4076.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
2007-02-17 19:42:17 +01:00
Arjan van de Ven d54b1fdb1d [PATCH] mark struct file_operations const 5
Many struct file_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:45 -08:00
Al Viro 9d6ed92196 [PATCH] radio modems sitting on serial port are not for s390
Won't build (request_irq()/free_irq()), even if you manage to find an
s390 box with 8250-compatible UART they are expecting.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-01 16:17:06 -08:00
Ralf Baechle f654c854d1 [HAMRADIO]: Fix baycom_epp.c compile failure.
Fix foobar in 15b1c0e822 and
e8cc49bb0f patch series.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-11 14:35:01 -08:00
Ralf Baechle 15b1c0e822 [AX.25]: Fix default address and broadcast address initialization.
Only the callsign but not the SSID part of an AX.25 address is ASCII
based but Linux by initializes the SSID which should be just a 4-bit
number from ASCII anyway.

Fix that and convert the code to use a shared constant for both default
addresses.  While at it, use the same style for null_ax25_address also.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-08 17:19:26 -08:00
Al Viro 7a87b6c228 [PATCH] hamradio/dmascc: fix up work_struct-induced breakage
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-06 11:06:46 -08:00
David Howells 4c1ac1b491 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:

	drivers/infiniband/core/iwcm.c
	drivers/net/chelsio/cxgb2.c
	drivers/net/wireless/bcm43xx/bcm43xx_main.c
	drivers/net/wireless/prism54/islpci_eth.c
	drivers/usb/core/hub.h
	drivers/usb/input/hid-core.c
	net/core/netpoll.c

Fix up merge failures with Linus's head and fix new compilation failures.

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-12-05 14:37:56 +00:00
Jean Delvare 95f6134e17 [6PACK]: Masking bug in 6pack driver.
Looks like a broken masking to me, binary not is used where bitwise
not was intended.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-11-25 15:16:50 -08:00
David Howells c4028958b6 WorkStruct: make allyesconfig
Fix up for make allyesconfig.

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-11-22 14:57:56 +00:00
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00
Ralf Baechle 1eeb7e4288 [BPQ] lockdep: fix false positive
Bpqether is encapsulating AX.25 frames into ethernet frames.  There is a
virtual bpqether device paired with each ethernet devices, so it's normal
to pass through dev_queue_xmit twice for each frame which triggers the
locking detector.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-10 14:50:33 -07:00
Thomas Gleixner 1fb9df5d30 [PATCH] irq-flags: drivers/net: Use the new IRQF_ constants
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02 13:58:51 -07:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Adrian Bunk e2fdbc039a [PATCH] drivers/net/hamradio/dmascc.c: fix section mismatch
dev_setup() is using the __initdata variables ax25_broadcast and
ax25_test.

Since the only caller of dev_setup() (setup_adapter()) is already
__init, the solution is to make dev_setup() __init, too.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-06-26 22:03:24 -04:00
Herbert Xu 932ff279a4 [NET]: Add netif_tx_lock
Various drivers use xmit_lock internally to synchronise with their
transmission routines.  They do so without setting xmit_lock_owner.
This is fine as long as netpoll is not in use.

With netpoll it is possible for deadlocks to occur if xmit_lock_owner
isn't set.  This is because if a printk occurs while xmit_lock is held
and xmit_lock_owner is not set can cause netpoll to attempt to take
xmit_lock recursively.

While it is possible to resolve this by getting netpoll to use
trylock, it is suboptimal because netpoll's sole objective is to
maximise the chance of getting the printk out on the wire.  So
delaying or dropping the message is to be avoided as much as possible.

So the only alternative is to always set xmit_lock_owner.  The
following patch does this by introducing the netif_tx_lock family of
functions that take care of setting/unsetting xmit_lock_owner.

I renamed xmit_lock to _xmit_lock to indicate that it should not be
used directly.  I didn't provide irq versions of the netif_tx_lock
functions since xmit_lock is meant to be a BH-disabling lock.

This is pretty much a straight text substitution except for a small
bug fix in winbond.  It currently uses
netif_stop_queue/spin_unlock_wait to stop transmission.  This is
unsafe as an IRQ can potentially wake up the queue.  So it is safer to
use netif_tx_disable.

The hamradio bits used spin_lock_irq but it is unnecessary as
xmit_lock must never be taken in an IRQ handler.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:30:14 -07:00
Ralf Baechle DL5RB 3ab33dcc82 [HAMRADIO]: Remove remaining SET_MODULE_OWNER calls from hamradio drivers.
Signed-off-by: Ralf Baechle DL5RB <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-03 23:24:35 -07:00
Rusty Russell 8d3b33f67f [PATCH] Remove MODULE_PARM
MODULE_PARM was actually breaking: recent gcc version optimize them out as
unused.  It's time to replace the last users, which are generally in the
most unloved drivers anyway.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:52 -08:00
Jeff Garzik 70c07e0262 Merge branch 'viro' 2006-02-09 14:17:05 -05:00
Al Viro 1b8623545b [PATCH] remove bogus asm/bug.h includes.
A bunch of asm/bug.h includes are both not needed (since it will get
pulled anyway) and bogus (since they are done too early).  Removed.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-02-07 20:56:35 -05:00
Marcelo Feitoza Parisi ff5688ae1c [PATCH] drivers/net/*: use time_after() and friends
They deal with wrapping correctly and are nicer to read.  Also make
jiffies-holding variables unsigned long.

Signed-off-by: Marcelo Feitoza Parisi <marcelo@feitoza.com.br>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-17 07:59:23 -05:00
Alan Cox 33f0f88f1c [PATCH] TTY layer buffering revamp
The API and code have been through various bits of initial review by
serial driver people but they definitely need to live somewhere for a
while so the unconverted drivers can get knocked into shape, existing
drivers that have been updated can be better tuned and bugs whacked out.

This replaces the tty flip buffers with kmalloc objects in rings. In the
normal situation for an IRQ driven serial port at typical speeds the
behaviour is pretty much the same, two buffers end up allocated and the
kernel cycles between them as before.

When there are delays or at high speed we now behave far better as the
buffer pool can grow a bit rather than lose characters. This also means
that we can operate at higher speeds reliably.

For drivers that receive characters in blocks (DMA based, USB and
especially virtualisation) the layer allows a lot of driver specific
code that works around the tty layer with private secondary queues to be
removed. The IBM folks need this sort of layer, the smart serial port
people do, the virtualisers do (because a virtualised tty typically
operates at infinite speed rather than emulating 9600 baud).

Finally many drivers had invalid and unsafe attempts to avoid buffer
overflows by directly invoking tty methods extracted out of the innards
of work queue structs. These are no longer needed and all go away. That
fixes various random hangs with serial ports on overflow.

The other change in here is to optimise the receive_room path that is
used by some callers. It turns out that only one ldisc uses receive room
except asa constant and it updates it far far less than the value is
read. We thus make it a variable not a function call.

I expect the code to contain bugs due to the size alone but I'll be
watching and squashing them and feeding out new patches as it goes.

Because the buffers now dynamically expand you should only run out of
buffering when the kernel runs out of memory for real.  That means a lot of
the horrible hacks high performance drivers used to do just aren't needed any
more.

Description:

tty_insert_flip_char is an old API and continues to work as before, as does
tty_flip_buffer_push() [this is why many drivers dont need modification].  It
does now also return the number of chars inserted

There are also

tty_buffer_request_room(tty, len)

which asks for a buffer block of the length requested and returns the space
found.  This improves efficiency with hardware that knows how much to
transfer.

and tty_insert_flip_string_flags(tty, str, flags, len)

to insert a string of characters and flags

For a smart interface the usual code is

    len = tty_request_buffer_room(tty, amount_hardware_says);
    tty_insert_flip_string(tty, buffer_from_card, len);

More description!

At the moment tty buffers are attached directly to the tty.  This is causing a
lot of the problems related to tty layer locking, also problems at high speed
and also with bursty data (such as occurs in virtualised environments)

I'm working on ripping out the flip buffers and replacing them with a pool of
dynamically allocated buffers.  This allows both for old style "byte I/O"
devices and also helps virtualisation and smart devices where large blocks of
data suddenely materialise and need storing.

So far so good.  Lots of drivers reference tty->flip.*.  Several of them also
call directly and unsafely into function pointers it provides.  This will all
break.  Most drivers can use tty_insert_flip_char which can be kept as an API
but others need more.

At the moment I've added the following interfaces, if people think more will
be needed now is a good time to say

 int tty_buffer_request_room(tty, size)

Try and ensure at least size bytes are available, returns actual room (may be
zero).  At the moment it just uses the flipbuf space but that will change.
Repeated calls without characters being added are not cumulative.  (ie if you
call it with 1, 1, 1, and then 4 you'll have four characters of space.  The
other functions will also try and grow buffers in future but this will be a
more efficient way when you know block sizes.

 int tty_insert_flip_char(tty, ch, flag)

As before insert a character if there is room.  Now returns 1 for success, 0
for failure.

 int tty_insert_flip_string(tty, str, len)

Insert a block of non error characters.  Returns the number inserted.

 int tty_prepare_flip_string(tty, strptr, len)

Adjust the buffer to allow len characters to be added.  Returns a buffer
pointer in strptr and the length available.  This allows for hardware that
needs to use functions like insl or mencpy_fromio.

Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:59 -08:00
Ralf Baechle c1854ebc7f [AX25] mkiss: Drop spinlock before sleeping call.
With the previous missing-unlock fix the spinlock is dropped only
after the tty->driver->write() call which might sleep.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-09 14:16:21 -08:00
Francois Romieu b341387225 [AX25/MKISS]: unbalanced spinlock_bh in ax_encaps()
The unlocking disappeared during commit
5793f4be23.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-07 12:57:40 -08:00
Adrian Bunk e6b365f61e [PATCH] drivers/net/hamradio/dmascc.c: remove dmascc_setup()
It seems dmascc_setup() is a leftover time before dmascc_init() was
there.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2005-11-05 21:00:01 -05:00
Jesper Juhl b4558ea93d drivers/net: Remove pointless checks for NULL prior to calling kfree() 2005-10-28 16:53:13 -04:00
Ralf Baechle ab7a435a01 [PATCH] Remove unused header.
mkiss.h has been integrated into mkiss.c earlier.

Signed-off-by: Ralf Baechle DL5RB <ralf@linux-mips.org>

 drivers/net/hamradio/mkiss.h |   62 -------------------------------------------
 1 files changed, 62 deletions(-)
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2005-10-19 22:14:20 -04:00
Ralf Baechle 74cfe03f80 [PATCH] Initialize the .owner field the tty_ldisc structure.
If .owner isn't set the module can be unloaded even while still active.

Signed-off-by: Ralf Baechle DL5RB <ralf@linux-mips.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2005-10-18 17:03:28 -04:00
Ralf Baechle 5793f4be23 [PATCH] SMACK support for mkiss
SMACK (Stuttgart Modified Amateurradio CRC KISS) is a KISS variant that
uses CRC16 checksums to secure data transfers between the modem and host.
It's also used to communicate over a pty to applications such as Wampes.

Patches for Linux 2.4 by Thomas Osterried DL9SAU, upgraded to the latest
mkiss 2.6 mkiss driver by me.

Signed-off-by: Thomas Osterried DL9SAU <thomas@x-berg.in-berlin.de>
Signed-off-by: Ralf Baechle DL5RB <ralf@linux-mips.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2005-10-18 17:02:14 -04:00
Ralf Baechle bc0a743860 [PATCH] rcu in bpqether driver.
From Suzanne Wood <suzannew@cs.pdx.edu>:

Clarify RCU implementation in bpqether.c.

Because bpq_new_device() calls list_add_rcu() and bpq_free_device() calls
list_del_rcu(), substitute list_for_each_entry_rcu() for
list_for_each_entry() in bpq_get_ax25_dev() and in bpq_seq_start().

Add rcu dereference protection in bpq_seq_next().

The rcu_read_lock()/unlock() in bpq_device_event() are removed because
netdev event handlers are called with RTNL locking in place.

FYI: bpq_free_device() calls list_del_rcu() which, per list.h, requires
synchronize_rcu() which can block or call_rcu() or call_rcu_bh() which
cannot block.  Herbert Xu notes that synchronization is done here by
unregister_netdevice().  This calls synchronize_net() which in turn uses
synchronize_rcu().

Signed-off-by: Ralf Baechle DL5RB <ralf@linux-mips.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2005-10-18 17:01:27 -04:00
Ralf Baechle d591958626 [PATCH] AX.25: Convert mkiss.c to DEFINE_RWLOCK
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Ralf Baechle DL5RB <ralf@linux-mips.org>

 drivers/net/hamradio/mkiss.c |    2 +-
 1 files changed, 1 insertion(+), 1 deletion(-)
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2005-10-04 07:42:22 -04:00
Ralf Baechle 96eb549c0c [PATCH] AX.25: Delete debug printk from mkiss driver
Signed-off-by: Ralf Baechle DL5RB <ralf@linux-mips.org>

--

 drivers/net/hamradio/mkiss.c |    1 -
 1 files changed, 1 deletion(-)
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2005-10-04 07:42:21 -04:00