29 July 2005, Cambridge, MA:
This afternoon Alan Stern submitted a patch to remove the URB_ASYNC_UNLINK
flag from the Linux kernel. Mr. Stern explained, "This flag is a relic
from an earlier, less-well-designed system. For over a year it hasn't
been used for anything other than printing warning messages."
An anonymous spokesman for the Linux kernel development community
commented, "This is exactly the sort of thing we see happening all the
time. As the kernel evolves, support for old techniques and old code can
be jettisoned and replaced by newer, better approaches. Proprietary
operating systems do not have the freedom or flexibility to change so
quickly."
Mr. Stern, a staff member at Harvard University's Rowland Institute who
works on Linux only as a hobby, noted that the patch (labelled as548) did
not update two files, keyspan.c and option.c, in the USB drivers' "serial"
subdirectory. "Those files need more extensive changes," he remarked.
"They examine the status field of several URBs at times when they're not
supposed to. That will need to be fixed before the URB_ASYNC_UNLINK flag
is removed."
Greg Kroah-Hartman, the kernel maintainer responsible for overseeing all
of Linux's USB drivers, did not respond to our inquiries or return our
calls. His only comment was "Applied, thanks."
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Back out Axboe-style quasi-S/G and replace it with one command and
repeated URBs. This is similar to what usb-storage does, only instead
of a few URBs allocated together, one URB is reused.
Jens's idea was very nice, but it collapsed when I had to support
packet commads for CD burning. I cannot issue two or more packet
commands where application expected only one.
However, burning does not work completely yet. The cdrecord starts,
recognizes the device, then aborts without writing a TOC.
Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When Al Viro saw the ub.c, he observed that it was a proof positive of
Linus not reading patches anymore: names like fo_ob_ar_ba_2 used to
cause serious fireworks. In my defence, any good scheme can be pushed
to the realm of absurd if pushed far enough.
Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Evidently, Yani Ioannou's display is wider than mine.
Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This the quasi-S/G patch for ub as suggested by Jens Axboe at OLS and
implemented that night before 4 a.m. Surprisingly, it worked right away...
Alas, I had to skip some OLS partying, but it was for the good cause.
Now the speed of ub is quite acceptable even on partitions with small
block size.
The ub does not really support S/G. Instead, it just tells the block
layer that it does. Then, most of the time, the block layer merges
requests and passes single-segmnent requests down to ub; everything
works as before. Very rarely ub gets an unmerged S/G request. In such
case, it issues several commands to the device.
I added a small array of counters to monitor the merging (sg_stat).
This may be dropped later.
Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Sanitized and fixed floppy dependencies: split the messy dependencies for
BLK_DEV_FD by introducing a new symbol (ARCH_MAY_HAVE_PC_FDC), making
BLK_DEV_FD depend on that one and taking declarations of ARCH_MAY_HAVE_PC_FDC
to arch/*/Kconfig. While we are at it, fixed several obvious cases when
BLK_DEV_FD should have been excluded (architectures lacking asm/floppy.h
are *not* going to have floppy.c compile, let alone work).
If you can come up with better name for that ("this architecture might
have working PC-compatible floppy disk controller"), you are more than
welcome - just s/ARCH_MAY_HAVE_PC_FDC/your_prefered_name/g in the patch
below...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch converts kcalloc(1, ...) calls to use the new kzalloc() function.
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I ran across a memory leak related to the cfq scheduler. The cfq
init function increments the refcnt of the associated request_queue.
This refcount gets decremented in cfq's exit function. Since blk_cleanup_queue
only calls the elevator exit function when its refcnt goes to zero, the
request_q never gets cleaned up. It didn't look like other io schedulers were
incrementing this refcnt, so I removed the refcnt increment and it fixed the
memory leak for me.
To reproduce the problem, simply use cfq and use the scsi_host scan sysfs
attribute to scan "- - -" repeatedly on a scsi host and watch the memory
vanish.
Signed-off-by: Brian King <brking@us.ibm.com>
Acked-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Per-queue parameters should be updated using the appropriate blk_queue_xxx
functions.
Signed-off-by: Stuart McLaren <stuart.mclaren@hp.com>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Patch to clean up missing overflow check in get_blkdev_list. The printf
which adds the "Block Devices" string in /proc/devices can overflow the
presented page if get_chrdev_list eats up the entire 4k space.
Signed-off-by: Neil Horman <nhorman@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
cleanup of deadline_dispatch_requests():
- replace drq selection with hopefully clearer while semantically the
same construct: take write request, if there is any, otherwise take read
one, or NULL if none exist.
- kill unused other_dir.
Signed-off-by: Nikita Danilov <nikita@clusterfs.com>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fiddle with coding style a bit.
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Currently only a device 'fdX' shows up in sysfs; the other possible
device for this drive (like fd0h1440 etc) must be guessed from there.
This patch corrects the floppy driver to create a platform device for
each floppy found; each platform device also has an attribute 'cmos'
which represents the cmos type for this drive. From this attribute the
other possible device types can be computed.
From: Hannes Reinecke <hare@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch goes through the current users of the crypto layer and sets
CRYPTO_TFM_REQ_MAY_SLEEP at crypto_alloc_tfm() where all crypto operations
are performed in process context.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Bonding just wants the device before the skb_bond()
decapsulation occurs, so simply pass that original
device into packet_type->func() as an argument.
It remains to be seen whether we can use this same
exact thing to get rid of skb->input_dev as well.
Signed-off-by: David S. Miller <davem@davemloft.net>
One critical fix and two minor fixes for 2.6.13-rc7:
- Max depth must currently be 2 to allow barriers to function on SCSI
- Prefer sync request over async in choosing the next request
- Never allow async request to preempt or disturb the "anticipation" for
a single cfq process context. This is as-designed, the code right now
is buggy in that area.
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Move initramfs options from Device Drivers | Block Drivers to General Setup
This is a more natural place for this option.
Furthermore separate out intramfs options to usr/Kconfig
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
My patch in commit fa72b903f7 incorrectly
removed blk_queue_tag->real_max_depth.
The original resize implementation was incorrect in the following
points.
* actual allocation size of tag_index was shorter than real_max_size,
but assumed to be of the same size, possibly causing memory access
beyond the allocated area.
* bits in tag_map between max_deptn and real_max_depth were
initialized to 1's, making the tags permanently reserved.
In an attempt to fix above two bugs, I had removed allocation optimization
in init_tag_map and real_max_size. Tag map/index were allocated and freed
immediately during resize.
Unfortunately, I wasn't considering that tag map/index can be resized
dynamically with tags beyond new_depth active. This led to accessing
freed area after shrinking tags and led to the following bug reporting
thread on linux-scsi.
http://marc.theaimsgroup.com/?l=linux-scsi&m=112319898111885&w=2
To fix the problem, I've revived real_max_depth without allocation
optimization in init_tag_map, and Andrew Vasquez confirmed that the
problem was fixed. As Jens is not going to be available for a week, he
asked me to make sure that this patch reaches you.
http://marc.theaimsgroup.com/?l=linux-scsi&m=112325778530886&w=2
Also, a comment was added to make sure that real_max_size is needed for
dynamic shrinking.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
CFQ will currently stall when using write barriers and the default
max_depth setting of 1, since we artificially need a depth of 2 when
pre-pending the first flush. So never deny the barrier request going to
the device.
This is a regression since 2.6.12, it was found in SUSE testing.
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds per disk queue functionality to cciss. Sometime back I
submitted a patch but it looks like only part of what I needed. In the 2.6
kernel if we have more than one logical volume the driver will Oops during
rmmod. It seems all of the queues actually point back to the same queue.
So after deleting the first volume you hit a null pointer on the second
one.
This has been tested in our labs. There is no difference in performance,
it just fixes the Oops.
Signed-off-by: Mike Miller <mike.miller@hp.com>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
turn many #if $undefined_string into #ifdef $undefined_string to fix some
warnings after -Wno-def was added to global CFLAGS
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes a microcode lockup in my CD-ROM adapters when a blank CD
is inserted. However, do not try to burn CDs yet! I'm pretty sure that
trying it will end in coasters.
- Fix a few cases where we were unable to resynchronize with replies
for previous commands. The main thing is to keep reading replies
in case of a stall. This is done with the new state CLRRS.
- Since I am forgetting the basic state machine already, document it.
- Move counter increments in the looping path in its own function.
- Fix a harmless buglet in case CSW read fails to submit: do not
override state.
- Implement the Alan Stern's idea for adaptive signature checking.
Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
AS is doing internal msec<->jiffies conversions twice, so the sysfs tunables
which represent time are coming out wrong. The switch from HZ=1000 exposed
this.
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
get_request is now expected to be holding on to queue_lock, with interrupts
disabled, when it returns NULL; but one path forgot that, causing all kinds
of nastiness under swap load - badness backtraces, strange failures, BUGs.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
get_io_context needlessly turned off interrupts and checked for racing io
context creations. Both of which aren't needed, because the io context can
only be created while in process context of the current process.
Also, split the function in 2. A light version, current_io_context does not
elevate the reference count specifically, but can be used when in process
context, because the process holds a reference itself.
Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change around locking a bit for a result of 1-2 less spin lock unlock pairs in
request submission paths.
Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In the case where the request is not able to be merged by the elevator, don't
retake the lock and retry the merge mechanism after allocating a new request.
Instead assume that the chance of a merge remains slim, and now that we've
done most of the work allocating a request we may as well just go with it.
Also be rid of the GFP_ATOMIC allocation: we've got working mempools for the
block layer now, so let's save atomic memory for things like networking.
Lastly, in get_request_wait, do an initial get_request call before going into
the waitqueue. This is reported to help efficiency.
Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently we cap request allocations at q->nr_requests, but we allow a
batching io context to allocate up to 32 more (default setting). This
can flood the queue with request allocations, with only a few batching
processes. The real fix would be to limit the number of batchers, but
as that isn't currently tracked, I suggest we just cap the maximum
number of allocated requests to eg 50% over the limit.
This was observed in real life, users typically see this as vmstat bo
numbers going off the wall with seconds of no queueing afterwards.
Behaviour this bursty is not beneficial.
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
drivers/block/cfq-iosched.c: In function 'cfq_put_queue':
drivers/block/cfq-iosched.c:303: sorry, unimplemented: inlining failed in call to 'cfq_pending_requests': function body not available
drivers/block/cfq-iosched.c:1080: sorry, unimplemented: called from here
drivers/block/cfq-iosched.c: In function '__cfq_may_queue':
drivers/block/cfq-iosched.c:1955: warning: the address of 'cfq_cfqq_must_alloc_slice', will always evaluate as 'true'
make[1]: *** [drivers/block/cfq-iosched.o] Error 1
make: *** [drivers/block/cfq-iosched.o] Error 2
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 patch fulfills a promise I made to Christoph sometime back. I am
removing the partition info from the CCISS_GETLUNINFO ioctl as I was informed
my "driver had no damn business reading that structure." ;)
The application folks are to use /proc or /sys for partition info from now on.
I am only aware of a few apps that use this ioctl and I'm not sure they ever
used the partition info.
Signed-off-by: Mike Miller <mike.miller@hp.com>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is pass 2 of my patch to add pci domain info to an existing ioctl. This
time I insert the domain between dev_fn and board_id as Willy suggested and
change the var to unsigned short to ease Christoph's concerns. Although I
thought unsigned int was the correct var type for this. I also thought it
didn't matter where I inserted it in the structure.
Signed-off-by: Mike Miller <mike.miller@hp.com>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes a PCI ID I got wrong before. It also adds support for
another new SAS controller due out this summer. I didn't have a marketing
name prior to my last submission. Also modifies the copyright date range.
Signed-off-by: Mike Miller <mike.miller@hp.com>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes CONFIG_PMAC_PBOOK (PowerBook support). This is now
split into CONFIG_PMAC_MEDIABAY for the actual hotswap bay that some
powerbooks have, CONFIG_PM for power management related code, and just left
out of any CONFIG_* option for some generally useful stuff that can be used
on non-laptops as well.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If cfq is managing a queue and a new scheduler is later selected, it is
possible for the cfqd unplug_work work to be queued after the kblockd
work struct has been flushed. The problem is the ordering of
cfq_shutdown_timer_wq() and blk_put_queue() in cfq_put_cfqd(). The
latter may rearm the work, leaving cfq_kick_queue() with dead data.
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Adjust slice values
- Instead of one async queue, one is defined per priority level. This
prevents kernel threads (such as reiserfs/x and others) that run at
higher io priority from conflicting with others. Previously, it was a
coin toss what io prio the async queue got, it was defined by who
first set up the queue.
- Let a time slice only begin, when the previous slice is completely
done. Previously we could be somewhat unfair to a new sync slice, if
the previous slice was async and had several ios queued. This might
need a little tweaking if throughput suffers a little due to this,
allowing perhaps an overlap of a single request or so.
- Optimize the calling of kblockd_schedule_work() by doing it only when
it is strictly necessary (no requests in driver and work left to do).
- Correct sync vs async logic. A 'normal' process can be purely async as
well, and a flusher can be purely sync as well. Sync or async is now a
property of the class defined and requests pending. Previously writers
could be considered sync, when they were really async.
- Get rid of the bit fields in cfqq and crq, use flags instead.
- Various other cleanups and fixes
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In cfq_find_next_crq(), cfq tries to find the next request by choosing
one of two requests before and after the current one. Currently, when
choosing the next request, if there's no next request, the next
candidate is NULL, resulting in selection of the previous request. This
results in weird scheduling. Once we reach the end, we always seek
backward.
The correct behavior is using the first request as the next candidate.
cfq_choose_req() already has logics for handling wrapped requests.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This updates the CFQ io scheduler to the new time sliced design (cfq
v3). It provides full process fairness, while giving excellent
aggregate system throughput even for many competing processes. It
supports io priorities, either inherited from the cpu nice value or set
directly with the ioprio_get/set syscalls. The latter closely mimic
set/getpriority.
This import is based on my latest from -mm.
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the DMA_{64,32}BIT_MASK constants from dma-mapping.h when calling
pci_set_dma_mask() or pci_set_consistent_dma_mask()
These patches include dma-mapping.h explicitly because it caused errors
on some architectures otherwise.
See http://marc.theaimsgroup.com/?t=108001993000001&r=1&w=2 for details
Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch>
Signed-off-by: Domen Puncer <domen@coderock.org>
1. Establish a simple API for process freezing defined in linux/include/sched.h:
frozen(process) Check for frozen process
freezing(process) Check if a process is being frozen
freeze(process) Tell a process to freeze (go to refrigerator)
thaw_process(process) Restart process
frozen_process(process) Process is frozen now
2. Remove all references to PF_FREEZE and PF_FROZEN from all
kernel sources except sched.h
3. Fix numerous locations where try_to_freeze is manually done by a driver
4. Remove the argument that is no longer necessary from two function calls.
5. Some whitespace cleanup
6. Clear potential race in refrigerator (provides an open window of PF_FREEZE
cleared before setting PF_FROZEN, recalc_sigpending does not check
PF_FROZEN).
This patch does not address the problem of freeze_processes() violating the rule
that a task may only modify its own flags by setting PF_FREEZE. This is not clean
in an SMP environment. freeze(process) is therefore not SMP safe!
Signed-off-by: Christoph Lameter <christoph@lameter.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
