Commit Graph

25319 Commits

Author SHA1 Message Date
Eric Sesterhenn 9e77c485f7 BUG_ON() Conversion in md/raid1.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-01 01:08:49 +02:00
Eric Sesterhenn 543cb2a451 BUG_ON() Conversion in md/dm-target.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-01 01:08:12 +02:00
Adrian Bunk 58ef2c4ce3 typos: s/ducument/document/
s/ducument/document/

Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-01 01:04:59 +02:00
Adrian Bunk 2a08b4e904 fix the email address of Wendy Xiong
Replace a bouncing version of the email address of Wendy Xiong with a
working one.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-01 01:04:20 +02:00
Adrian Bunk 5637a2ee5d fix a typo in the AIC7XXX_DEBUG_MASK help text
This patch fixes a typo in the AIC7XXX_DEBUG_MASK help text.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-01 01:03:38 +02:00
Adrian Bunk 3e6e952d1d help text: SOFTWARE_SUSPEND doesn't need ACPI
The note that SOFTWARE_SUSPEND doesn't need APM is helpful, but nowadays
the information that it doesn't need ACPI, too, is even more helpful.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-01 01:03:08 +02:00
Anders Larsen 3a3f8a126d MTD: remove obsolete Kconfig options
Remove the obsolete Kconfig options MTD_CFI_AMDSTD_RETRY
and MTD_CFI_AMDSTD_RETRY_MAX

The code that depended on these was removed in early 2004, but
Kconfig was not updated accordingly.

Signed-off-by: Anders Larsen <al@alarsen.net>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-01 01:02:42 +02:00
Steve French 06bcfedd05 [CIFS] Fix typo in earlier cifs_unlink change and protect one
extra path.

Since cifs_unlink can also be called from rename path and there
was one report of oops am making the extra check for null inode.

Signed-off-by: Steve French <sfrench@us.ibm.com>
2006-03-31 22:43:50 +00:00
Steve French e9917a000f [CIFS] Incorrect signature sent on SMB Read
Fixes Samba bug 3621 and kernel.org bug 6147

For servers which require SMB/CIFS packet signing, we were sending the
wrong signature (all zeros) on SMB Read request.  The new cifs routine
to do signatures across an iovec was not complete - and SMB Read, unlike
the new SMBWrite2, did not fall back to the older routine (ie use
SendReceive vs. the more efficient SendReceive2 ie used the older
cifs_sign_smb vs. the disabled  cifs_sign_smb2) for calculating signatures.

This finishes up cifs_sign_smb2/cifs_calc_signature2 so that the callers
of SendReceive2 can get SMB/CIFS packet signatures.

Now that cifs_sign_smb2 is supported, we could start using it in
the write path but this smaller fix does not include the change
to use SMBWrite2 when signatures are required (which when enabled
will make more Writes more efficient and alloc less memory).
Currently Write2 is only used when signatures are not
required at the moment but after more testing we will enable
that as well).

Thanks to James Slepicka and Sam Flory for initial investigation.

Signed-off-by: Steve French <sfrench@us.ibm.com>
2006-03-31 21:22:00 +00:00
Bryan O'Sullivan 77d8798b55 IB/ipath: kbuild infrastructure
Integrate the ipath core and OpenIB drivers into the kernel build
infrastructure.  Add entry to MAINTAINERS.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:21 -08:00
Bryan O'Sullivan 6522108f19 IB/ipath: infiniband verbs support
The ipath_verbs.c file implements the driver-specific components of the
kernel's Infiniband verbs layer.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:21 -08:00
Bryan O'Sullivan e28c00ad67 IB/ipath: misc infiniband code, part 2
Management datagram support, queue pairs, and reliable and unreliable
connections.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:21 -08:00
Bryan O'Sullivan cef1cce5c8 IB/ipath: misc infiniband code, part 1
Completion queues, local and remote memory keys, and memory region
support.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:20 -08:00
Bryan O'Sullivan 97f9efbc47 IB/ipath: infiniband RC protocol support
This is an implementation of the Infiniband RC ("reliable connection")
protocol.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:20 -08:00
Bryan O'Sullivan 74ed6b5eb1 IB/ipath: infiniband UC and UD protocol support
These files implement the Infiniband UC ("unreliable connection") and UD
("unreliable datagram") protocols.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:20 -08:00
Bryan O'Sullivan aa735edf5d IB/ipath: infiniband header files
These header files are used by the layered Infiniband driver.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:20 -08:00
Bryan O'Sullivan 889ab795a3 IB/ipath: layering interfaces used by higher-level driver code
The layering interfaces are used to implement the Infiniband protocols
and the ethernet emulation driver.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:20 -08:00
Bryan O'Sullivan 7f510b46e4 IB/ipath: support for userspace apps using core driver
These files introduce a char device that userspace apps use to gain
direct memory-mapped access to the InfiniPath hardware, and routines for
pinning and unpinning user memory in cases where the hardware needs to
DMA into the user address space.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:19 -08:00
Bryan O'Sullivan 3e9b4a5eb4 IB/ipath: sysfs and ipathfs support for core driver
The ipathfs filesystem contains files that are not appropriate for
sysfs, because they contain binary data.  The hierarchy is simple; the
top-level directory contains driver-wide attribute files, while numbered
subdirectories contain per-device attribute files.

Our userspace code currently expects this filesystem to be mounted on
/ipathfs, but a final location has not yet been chosen.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:19 -08:00
Bryan O'Sullivan 108ecf0d90 IB/ipath: misc driver support code
EEPROM support, interrupt handling, statistics gathering, and write
combining management for x86_64.

A note regarding i2c: The Atmel EEPROM hardware we use looks like an
i2c device electrically, but is not i2c compliant at all from a
functional perspective.  We tried using the kernel's i2c support to
talk to it, but failed.

Normal i2c devices have a single 7-bit or 10-bit i2c address that they
respond to.  Valid 7-bit addresses range from 0x03 to 0x77.  Addresses
0x00 to 0x02 and 0x78 to 0x7F are special reserved addresses
(e.g. 0x00 is the "general call" address.)  The Atmel device, on the
other hand, responds to ALL addresses.  It's designed to be the only
device on a given i2c bus.  A given i2c device address corresponds to
the memory address within the i2c device itself.

At least one reason why the linux core i2c stuff won't work for this
is that it prohibits access to reserved addresses like 0x00, which are
really valid addresses on the Atmel devices.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:19 -08:00
Bryan O'Sullivan 097709fea0 IB/ipath: chip initialisation code, and diag support
ipath_init_chip.c sets up an InfiniPath device for use.

ipath_diag.c permits userspace diagnostic tools to read and write a
chip's registers.  It is different in purpose from the mmap interfaces
to the /sys/bus/pci resource files.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:19 -08:00
Bryan O'Sullivan dc741bbd4f IB/ipath: support for PCI Express devices
This file contains routines and definitions specific to InfiniPath
devices that have PCI Express interfaces.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:19 -08:00
Bryan O'Sullivan cc533a5721 IB/ipath: support for HyperTransport devices
The ipath_ht400.c file contains routines and definitions specific to
HyperTransport-based InfiniPath devices.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:18 -08:00
Bryan O'Sullivan d41d3aeb76 IB/ipath: core driver header files
ipath_common.h and ips_common.h contain definitions shared between
userspace and the kernel.

ipath_kernel.h is the core driver header file.

ipath_debug.h contains mask values used for controlling driver debugging.

ipath_registers.h contains bitmask definitions used in chip registers.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:18 -08:00
Bryan O'Sullivan 7bb206e3b2 IB/ipath: core device driver
The ipath driver is a low-level driver for PathScale InfiniPath host
channel adapters (HCAs) based on the HT-400 and PE-800 chips, including
the InfiniPath HT-460, the small form factor InfiniPath HT-460, the
InfiniPath HT-470 and the Linux Networx LS/X.

The ipath_driver.c file contains much of the low-level device handling
code.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-31 13:14:18 -08:00
Linus Torvalds 4b75679f60 Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
  [NET]: Allow skb headroom to be overridden
  [TCP]: Kill unused extern decl for tcp_v4_hash_connecting()
  [NET]: add SO_RCVBUF comment
  [NET]: Deinline some larger functions from netdevice.h
  [DCCP]: Use NULL for pointers, comfort sparse.
  [DECNET]: Fix refcount
2006-03-31 12:52:30 -08:00
Jes Sorensen 30c14e40ed [PATCH] avoid unaligned access when accessing poll stack
Commit 70674f95c0a2ea694d5c39f4e514f538a09be36f:

  [PATCH] Optimize select/poll by putting small data sets on the stack

resulted in the poll stack being 4-byte aligned on 64-bit architectures,
causing misaligned accesses to elements in the array.

This patch fixes it by declaring the stack in terms of 'long' instead
of 'char'.

Force alignment of poll and select stacks to long to avoid unaligned
access on 64 bit architectures.

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:30:48 -08:00
Linus Torvalds d21c356b08 Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev:
  [PATCH] libata: fix ata_xfer_tbl termination
  [PATCH] libata: make ata_qc_issue complete failed qcs
  [PATCH] libata: fix ata_qc_issue failure path
  [PATCH] ata_piix: fix ich6/m_map_db
  [libata] ahci: add ATI SB600 PCI IDs
2006-03-31 12:28:01 -08:00
David Howells 108b42b4b9 [PATCH] Document Linux's memory barriers [try #7]
The attached patch documents the Linux kernel's memory barriers.

I've updated it from the comments I've been given.

The per-arch notes sections are gone because it's clear that there are so many
exceptions, that it's not worth having them.

I've added a list of references to other documents.

I've tried to get rid of the concept of memory accesses appearing on the bus;
what matters is apparent behaviour with respect to other observers in the
system.

Interrupts barrier effects are now considered to be non-existent. They may be
there, but you may not rely on them.

I've added a couple of definition sections at the top of the document: one to
specify the minimum execution model that may be assumed, the other to specify
what this document refers to by the term "memory".

I've made greater mention of the use of mmiowb().

I've adjusted the way in which caches are described, and described the fun
that can be had with cache coherence maintenance being unordered and data
dependency not being necessarily implicit.

I've described (smp_)read_barrier_depends().

I've rearranged the order of the sections, so that memory barriers are
discussed in abstract first, and then described the memory barrier facilities
available on Linux, before going on to more real-world discussions and examples.

I've added information about the lack of memory barriering effects with atomic
ops and bitops.

I've added information about control dependencies.

I've added more diagrams to illustrate caching interactions between CPUs.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:27:01 -08:00
Kirill Korotaev 4286229868 [PATCH] wrong error path in dup_fd() leading to oopses in RCU
Wrong error path in dup_fd() - it should return NULL on error,
not an address of already freed memory :/

Triggered by OpenVZ stress test suite.

What is interesting is that it was causing different oopses in RCU like
below:
Call Trace:
   [<c013492c>] rcu_do_batch+0x2c/0x80
   [<c0134bdd>] rcu_process_callbacks+0x3d/0x70
   [<c0126cf3>] tasklet_action+0x73/0xe0
   [<c01269aa>] __do_softirq+0x10a/0x130
   [<c01058ff>] do_softirq+0x4f/0x60
   =======================
   [<c0113817>] smp_apic_timer_interrupt+0x77/0x110
   [<c0103b54>] apic_timer_interrupt+0x1c/0x24
  Code:  Bad EIP value.
   <0>Kernel panic - not syncing: Fatal exception in interrupt

Signed-Off-By: Pavel Emelianov <xemul@sw.ru>
Signed-Off-By: Dmitry Mishin <dim@openvz.org>
Signed-Off-By: Kirill Korotaev <dev@openvz.org>
Signed-Off-By: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:25:46 -08:00
Nicolas Pitre e358c1a2c4 [PATCH] mutex: some cleanups
Turn some macros into inline functions and add proper type checking as
well as being more readable.  Also a minor comment adjustment.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:01 -08:00
Jesper Juhl a58e00e7da [PATCH] Decrease number of pointer derefs in jsm_tty.c
Decrease the number of pointer derefs in drivers/serial/jsm/jsm_tty.c

Benefits of the patch:
 - Fewer pointer dereferences should make the code slightly faster.
 - Size of generated code is smaller
 - Improved readability

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: "V. ANANDA KRISHNAN" <mansarov@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:01 -08:00
Adrian Bunk a244e1698a [PATCH] fs/namei.c: make lookup_hash() static
As announced, lookup_hash() can now become static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:01 -08:00
Adrian Bunk 0cb3463f04 [PATCH] unexport get_wchan
The only user of get_wchan is the proc fs - and proc can't be built modular.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:01 -08:00
NeilBrown ec350a7fc1 [PATCH] md: Raid-6 did not create sysfs entries for stripe cache
Signed-off-by: Brad Campbell <brad@wasp.net.au>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:01 -08:00
NeilBrown 926ce2d8a7 [PATCH] md: Remove some code that can sleep from under a spinlock
And remove the comments that were put in inplace of a fix too....

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:01 -08:00
NeilBrown 6b1117d505 [PATCH] md: Don't clear bits in bitmap when writing to one device fails during recovery
Currently a device failure during recovery leaves bits set in the bitmap.
This normally isn't a problem as the offending device will be rejected because
of errors.  However if device re-adding is being used with non-persistent
bitmaps, this can be a problem.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:01 -08:00
Michael Hanselmann 39451a73a2 [PATCH] fbdev: Remove old radeon driver
This patch removes the old radeon driver which has been replaced by a
newer one.

Signed-off-by: Michael Hanselmann <linux-kernel@hansmi.ch>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:01 -08:00
Antonino A. Daplas a536093a2f [PATCH] fbcon: Fix big-endian bogosity in slow_imageblit()
The monochrome->color expansion routine that handles bitmaps which have
(widths % 8) != 0 (slow_imageblit) produces corrupt characters in big-endian.
This is caused by a bogus bit test in slow_imageblit().

Fix.

This patch may deserve to go to the stable tree.  The code has already been
well tested in little-endian machines.  It's only in big-endian where there is
uncertainty and Herbert confirmed that this is the correct way to go.

It should not introduce regressions.

Signed-off-by: Antonino Daplas <adaplas@pol.net>
Acked-by: Herbert Poetzl <herbert@13thfloor.at>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:00 -08:00
Richard Purdie 2cbbb3b59c [PATCH] pxafb: Minor driver fixes
Fixes for the pxafb driver:

* Return -EINVAL for resolutions that are too large as per framebuffer
  driver policy.

* Increase the error timeout for disabling the LCD controller.  The current
  timeout is sometimes too short on the Sharp Zaurus Cxx00 hardware and an
  extra delay in an error path shouldn't pose any problems.

* Fix a dev reference which causes a compile error when DEBUG is defined.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:00 -08:00
Richard Purdie 2c0f5fb08e [PATCH] backlight: corgi_bl: Generalise to support other Sharp SL hardware
Generalise the Corgi backlight driver by moving the default intensity and
limit mask settings into the platform specific data structure.  This enables
the driver to support other Zaurus hardware, specifically the SL-6000x (Tosa)
model.

Also change the spinlock to a mutex (the spinlock is overkill).

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:00 -08:00
Richard Purdie 5f27a27bd7 [PATCH] backlight: HP Jornada 680 Backlight driver updates/fixes
Updates to the HP Jornada 680 Backlight driver:

- Correct the suspend/resume functions so the driver compiles
  (SUSPEND_POWER_DOWN/RESUME_POWER_ON no longer exist).

- Convert the driver to match the recent platform device changes.

- Replace the unsafe static struct platform_device with dynamic allocation.

- Convert the driver to the new backlight code.

This has not been tested on a device due to lack of hardware but wouldn't
compile beforehand.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:00 -08:00
Richard Purdie 6ca017658b [PATCH] backlight: Backlight Class Improvements
Backlight class attributes are currently easy to implement incorrectly.
Moving certain handling into the backlight core prevents this whilst at the
same time makes the drivers simpler and consistent.  The following changes are
included:

The brightness attribute only sets and reads the brightness variable in the
backlight_properties structure.

The power attribute only sets and reads the power variable in the
backlight_properties structure.

Any framebuffer blanking events change a variable fb_blank in the
backlight_properties structure.

The backlight driver has only two functions to implement.  One function is
called when any of the above properties change (to update the backlight
brightness), the second is called to return the current backlight brightness
value.  A new attribute "actual_brightness" is added to return this brightness
as determined by the driver having combined all the above factors (and any
driver/device specific factors).

Additionally, the backlight core takes care of checking the maximum brightness
is not exceeded and of turning off the backlight before device removal.

The corgi backlight driver is updated to reflect these changes.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:00 -08:00
Alberto Mardegan 9b0e1c5dd2 [PATCH] w100fb: Add acceleration support to ATI Imageon
Add acceleration support in w100fb.c (i.e.  ATI Imageons) for the copyarea and
fillrect operations.

Signed-off-by: Alberto Mardegan <mardy@users.sourceforge.net>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:00 -08:00
Antonino A. Daplas 1a37d5f510 [PATCH] fbcon: Save current display during initialization
The current display was not saved during initialization.  This leads to hard
to track console corruption, such as a misplaced cursor, which is correctible
by switching consoles.  Fix this minor bug.

Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:00 -08:00
Eric W. Biederman 3e7e241f8c [PATCH] dcache: Add helper d_hash_and_lookup
It is very common to hash a dentry and then to call lookup.  If we take fs
specific hash functions into account the full hash logic can get ugly.
Further full_name_hash as an inline function is almost 100 bytes on x86 so
having a non-inline choice in some cases can measurably decrease code size.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:00 -08:00
Eric W. Biederman 92476d7fc0 [PATCH] pidhash: Refactor the pid hash table
Simplifies the code, reduces the need for 4 pid hash tables, and makes the
code more capable.

In the discussions I had with Oleg it was felt that to a large extent the
cleanup itself justified the work.  With struct pid being dynamically
allocated meant we could create the hash table entry when the pid was
allocated and free the hash table entry when the pid was freed.  Instead of
playing with the hash lists when ever a process would attach or detach to a
process.

For myself the fact that it gave what my previous task_ref patch gave for free
with simpler code was a big win.  The problem is that if you hold a reference
to struct task_struct you lock in 10K of low memory.  If you do that in a user
controllable way like /proc does, with an unprivileged but hostile user space
application with typical resource limits of 1000 fds and 100 processes I can
trigger the OOM killer by consuming all of low memory with task structs, on a
machine wight 1GB of low memory.

If I instead hold a reference to struct pid which holds a pointer to my
task_struct, I don't suffer from that problem because struct pid is 2 orders
of magnitude smaller.  In fact struct pid is small enough that most other
kernel data structures dwarf it, so simply limiting the number of referring
data structures is enough to prevent exhaustion of low memory.

This splits the current struct pid into two structures, struct pid and struct
pid_link, and reduces our number of hash tables from PIDTYPE_MAX to just one.
struct pid_link is the per process linkage into the hash tables and lives in
struct task_struct.  struct pid is given an indepedent lifetime, and holds
pointers to each of the pid types.

The independent life of struct pid simplifies attach_pid, and detach_pid,
because we are always manipulating the list of pids and not the hash table.
In addition in giving struct pid an indpendent life it makes the concept much
more powerful.

Kernel data structures can now embed a struct pid * instead of a pid_t and
not suffer from pid wrap around problems or from keeping unnecessarily
large amounts of memory allocated.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:00 -08:00
Eric W. Biederman 8c7904a00b [PATCH] task: RCU protect task->usage
A big problem with rcu protected data structures that are also reference
counted is that you must jump through several hoops to increase the reference
count.  I think someone finally implemented atomic_inc_not_zero(&count) to
automate the common case.  Unfortunately this means you must special case the
rcu access case.

When data structures are only visible via rcu in a manner that is not
determined by the reference count on the object (i.e.  tasks are visible until
their zombies are reaped) there is a much simpler technique we can employ.
Simply delaying the decrement of the reference count until the rcu interval is
over.

What that means is that the proc code that looks up a task and later
wants to sleep can now do:

rcu_read_lock();
task = find_task_by_pid(some_pid);
if (task) {
	get_task_struct(task);
}
rcu_read_unlock();

The effect on the rest of the kernel is that put_task_struct becomes cheaper
and immediate, and in the case where the task has been reaped it frees the
task immediate instead of unnecessarily waiting an until the rcu interval is
over.

Cleanup of task_struct does not happen when its reference count drops to
zero, instead cleanup happens when release_task is called.  Tasks can only
be looked up via rcu before release_task is called.  All rcu protected
members of task_struct are freed by release_task.

Therefore we can move call_rcu from put_task_struct into release_task.  And
we can modify release_task to not immediately release the reference count
but instead have it call put_task_struct from the function it gives to
call_rcu.

The end result:

- get_task_struct is safe in an rcu context where we have just looked
  up the task.

- put_task_struct() simplifies into its old pre rcu self.

This reorganization also makes put_task_struct uncallable from modules as
it is not exported but it does not appear to be called from any modules so
this should not be an issue, and is trivially fixed.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:59 -08:00
Herbert Poetzl e4e5d3fc80 [PATCH] cleanup in proc_check_chroot()
proc_check_chroot() does the check in a very unintuitive way (keeping a
copy of the argument, then modifying the argument), and has uncommented
sideeffects.

Signed-off-by: Herbert Poetzl <herbert@13thfloor.at>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:59 -08:00
Andrew Morton 158d9ebd19 [PATCH] resurrect __put_task_struct
This just got nuked in mainline.  Bring it back because Eric's patches use it.

Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:59 -08:00