Combined mode sucks. Especially when both libata and the legacy IDE
drivers try to drive ports on the same device, since that makes DMA
rather difficult.
This patch addresses the problem by allowing the user to control which
driver binds to the ports in a combined mode configuration. In many
cases, they'll probably want the libata driver to control both ports
since it can use DMA for talking with ATAPI devices (when
libata.atapi_enabled=1 of course). It also allows the user to get old
school behavior by letting the legacy IDE driver bind to both ports.
But neither is forced, the patch doesn't change current behavior unless
one of combined_mode=ide or combined_mode=libata is passed
on the boot line. Either of those options may require you to access
your devices via different device nodes (/dev/hd* in the ide case
and /dev/sd* in the libata case), though of course if you have udev
installed nicely you may not notice anything. :)
Let me know if the documentation is too cryptic, I'd be happy to expand
on it if necessary. I think most users will want to boot with
'combined_mode=libata' and add 'options libata atapi_enabled=1'
to their modules.conf to get good DVD playing and disk behavior
(haven't tested CD or DVD writing though).
I'd much rather things behave sanely by default (i.e. DMA for devices on
both ports), but apparently that's difficult given the various chip
bugs and hardware configs out there (not to mention that people's
drives may suddenly change from /dev/hdc to /dev/sdb), so this boot
option may be the correct long term fix.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Reported by Jacques de Mer and Daniel Drake <dsd@gentoo.org>.
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch (as611) fixes a minor mistake and misspelling in the USB
documentation.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Patch to ifenslave so that under older ABI versions, a failure to propogate ip
information from master to slave does not result in a filure to enslave the
slave device.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Correct lots of URLs in Documentation/ Also a few minor whitespace cleanups
and typo/spello fixes. Sadly there are still a lot of bad URLs remaining.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Update the index file with descriptions of the stable_api_nonsense.txt
and stable_kernel_rules.txt files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Here's a document that describes the process and procedures of how to do Linux
kernel development. It has gone through a number of rounds of review on the
linux-kernel mailing list, and contains contributions and help from Paolo
Ciarrocchi, Randy Dunlap, Gerrit Huizenga, Pat Mochel, Hanna Linder, Kay
Sievers, Vojtech Pavlik, Jan Kara, Josh Boyer, Kees Cook, Andrew Morton, Andi
Kleen, Vadim Lobanov, Jesper Juhl, Adrian Bunk, Keri Harris, Frans Pop, David
A. Wheeler, Junio Hamano, Michael Kerrisk, and Alex Shepard.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Document that the VMALLOC_END address must be aligned to 2MB since
it must align with a PGD boundary.
Allocate the vectors page early so that the flush_cache_all() later
will cause any dirty cache lines in the direct mapping will be safely
written back.
Move the flush_cache_all() to the second local_flush_cache_tlb() and
remove the now redundant first local_flush_cache_tlb().
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch deletes the bluetooth.txt help file of the bluetty driver and
hands over its major device nodes for character devices to the RFCOMM TTY
implementation of the Bluetooth subsystem.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The 8250 serial driver now has the ability to deal with the differences
between the standard 8250 family of UARTs and their slightly strange
brother on Alchemy SOCs. The loss of features is not considered an
issue.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Something I've found handy countless times when users do this..
Signed-off-by: Dave Jones <davej@redhat.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Picked from the ubuntu-2.6 tree
The change in location for ll_rw_blk.c from drivers/block/ to block/ caused
failure to generate documentation.
Signed-off-by: Ben Collins <bcollins@ubuntu.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This was marked deprecated "after 2.6" back in the 2.5 days. But now it
seems there isn't going to be any "after 2.6", and we deprecate by date
now. So set a date.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
CONFIG_CHECKING covered some debugging code used in the early times
of the port. But it wasn't even SMP safe for quite some time
and the bugs it checked for seem to be gone.
This patch removes all the code to verify GS at kernel entry. There
haven't been any new bugs in this area for a long time.
Previously it also covered the sysctl for the page fault tracing.
That didn't make much sense because that code was unconditionally
compiled in. I made that a boot option now because it is typically
only useful at boot.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The logging for boot errors was turned off because it was broken
on some AMD systems. But give Intel EM64T systems a chance because they are
supposed to be correct there.
The advantage is that there is a chance to actually log uncorrected
machine checks after the reset.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With a NR_CPUS==128 kernel with CPU hotplug enabled we would waste 4MB
on per CPU data of all possible CPUs. The reason was that HOTPLUG
always set up possible map to NR_CPUS cpus and then we need to allocate
that much (each per CPU data is roughly ~32k now)
The underlying problem is that ACPI didn't tell us how many hotplug CPUs
the platform supports. So the old code just assumed all, which would
lead to this memory wastage.
This implements some new heuristics:
- If the BIOS specified disabled CPUs in the ACPI/mptables assume they
can be enabled later (this is bending the ACPI specification a bit,
but seems like a obvious extension)
- The user can overwrite it with a new additionals_cpus=NUM option
- Otherwise use half of the available CPUs or 2, whatever is more.
Cc: ashok.raj@intel.com
Cc: len.brown@intel.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I got some questions on this, so just fix up the documentation.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As xmlto doesn't work for print documentation, we need docbook-utils again for
these targets.
This patch allows the user to choose the method he wants to use. (I'm still
hoping that someone will fix passivetex ;-)
Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a comment showing how to change paper type.
Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Introduce an atomic_inc_not_zero operation. Make this a special case of
atomic_add_unless because lockless pagecache actually wants
atomic_inc_not_negativeone due to its offset refcount.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is an updated version of the RFC3465 ABC patch originally
for Linux 2.6.11-rc4 by Yee-Ting Li. ABC is a way of counting
bytes ack'd rather than packets when updating congestion control.
The orignal ABC described in the RFC applied to a Reno style
algorithm. For advanced congestion control there is little
change after leaving slow start.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is a first go at some documentation. Please advise if gmail
has mangled patch and I will revert to an attachment:
Signed-off-by: Ian McDonald <imcdnzl@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Document in Documentation/md.txt the files that now appear in sysfs, and make
a couple of small refinements to exactly when 'level' and 'raid_disks' are
empty, to make it match the documentation.
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add documentation as Documentation/fb/fbcon.txt describing the framebuffer
console and its boot options.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make some changes to the NEED_RESCHED and POLLING_NRFLAG to reduce
confusion, and make their semantics rigid. Improves efficiency of
resched_task and some cpu_idle routines.
* In resched_task:
- TIF_NEED_RESCHED is only cleared with the task's runqueue lock held,
and as we hold it during resched_task, then there is no need for an
atomic test and set there. The only other time this should be set is
when the task's quantum expires, in the timer interrupt - this is
protected against because the rq lock is irq-safe.
- If TIF_NEED_RESCHED is set, then we don't need to do anything. It
won't get unset until the task get's schedule()d off.
- If we are running on the same CPU as the task we resched, then set
TIF_NEED_RESCHED and no further action is required.
- If we are running on another CPU, and TIF_POLLING_NRFLAG is *not* set
after TIF_NEED_RESCHED has been set, then we need to send an IPI.
Using these rules, we are able to remove the test and set operation in
resched_task, and make clear the previously vague semantics of
POLLING_NRFLAG.
* In idle routines:
- Enter cpu_idle with preempt disabled. When the need_resched() condition
becomes true, explicitly call schedule(). This makes things a bit clearer
(IMO), but haven't updated all architectures yet.
- Many do a test and clear of TIF_NEED_RESCHED for some reason. According
to the resched_task rules, this isn't needed (and actually breaks the
assumption that TIF_NEED_RESCHED is only cleared with the runqueue lock
held). So remove that. Generally one less locked memory op when switching
to the idle thread.
- Many idle routines clear TIF_POLLING_NRFLAG, and only set it in the inner
most polling idle loops. The above resched_task semantics allow it to be
set until before the last time need_resched() is checked before going into
a halt requiring interrupt wakeup.
Many idle routines simply never enter such a halt, and so POLLING_NRFLAG
can be always left set, completely eliminating resched IPIs when rescheduling
the idle task.
POLLING_NRFLAG width can be increased, to reduce the chance of resched IPIs.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
States a date for removing V4L1 API
Signed-off-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remote and more info for PCTV Cardbus. Whitespace cleanup.
Signed-off-by: Pavel Mihaylov <bin@bash.info>
Signed-off-by: Nickolay V. Shmyrev <nshmyrev@yandex.ru>
Signed-off-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Fixed broken API link and indentation.
Signed-off-by: Nickolay V. Shmyrev <nshmyrev@yandex.ru>
Signed-off-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
