Update the hacking guide, before CONFIG_PREEMPT_RT goes in and it needs
rewriting again.
Changes include modernization of quotes, removal of most references to
bottom halves (some mention required because we still use bh in places to
mean softirq).
It would be nice to have a discussion of sparse and various annotations.
Please send patches straight to akpm.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (authored)
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch add the plateform specific stuff needed to configure and use the
driver.
Signed-Off-By: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ben Dooks <ben@trinity.fluff.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This set of two patches add support for the framebuffer of the Samsung S3C2410
ARM SoC. This driver was started about one year ago and is now used on iPAQ
h1930/h1940, Acer n30 and probably other s3c2410-based machines I'm not aware
of. I've also heard yesterday that it's working also on iPAQ rx3715/rx3115
(s3c2440-based machines).
Signed-Off-By: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Ben Dooks <ben@trinity.fluff.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Quiet an incorrect warning in aty128fb and radeonfb about the PCI ROM
content. Macs work just find without that signature.
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Stop LCD displays from flickering during high loads.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add ddc/i2c support for i810fb. This will allow the driver to get display
information, especially for monitors with fickle timings. The i2c support
depends on CONFIG_FB_I810_GTF.
Changed __init* to __devinit*
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Alexander Nyberg <alexn@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The function bit_putcs() in drivers/video/console/bitblit.c is becoming large.
Break it up into its component functions (bit_putcs_unaligned and
bit_putcs_aligned).
Incorporated fb_pad_aligned_buffer() optimization by Roman Zippel.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
To solve touchscreen interference problems devices like the Sharp Zaurus
SL-C3000 need to know the length of the horitzontal sync pulses. This patch
adds a hook to pxafb so the touchscreen driver can function correctly.
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>
The var structure in calc_mode_timings is not properly initialized (zero set)
which leads to undefined behavior when it is passed to fb_get_mode().
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
nvidiafb_imageblit converts the bitdata stream from big_endian to little
endian. This produces mirrored characters when machine is big_endian. Do not
endian convert on big endian machines.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If console is blanked or in KD_GRAPHICS mode, delete cursor timer. No sense
flashing the cursor when there's nothing to be seen.
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 "mode_option" available when compiled as a module.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If no EDID block is probed, if the display is digital and if no mode option is
specified by the user, get the timings by CVT instead of using the global mode
database.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The Coordinated Video Timings (CVT) is the latest standard approved by VESA
concerning video timings generation. It addresses the limitation of GTF which
is designed mainly for CRT displays. CRT's have a high blanking requirement
(as much as 25% of the horizontal frame length) which artificially increases
the pixelclock. Digital displays, on the other hand, needs to conserve the
pixelclock as much as possible. The GTF also does not take into account the
different aspect ratios in its calculation.
The new function added is fb_find_mode_cvt(). It is called by fb_find_mode()
if it recognizes a mode option string formatted for CVT. The format is:
<xres>x<yres>[M][R][-<bpp>][<at-sign><refresh>][i][m]
The 'M' tells the function to calculate using CVT. On it's own, it will
compute a timing for CRT displays at 60Hz. If the 'R' is specified, 'reduced
blanking' computation will be used, best for flatpanels. The 'i' and the 'm'
is for 'interlaced mode' and 'with margins' respectively.
To determine if CVT was used, check for dmesg for something like this:
CVT Mode - <pix>M<n>[-R], ie: .480M3-R (800x600 reduced blanking)
where: pix - product of xres and yres, in MB
M - is a CVT mode
n - the aspect ratio (3 - 4:3; 4 - 5:4; 9 - 16:9, 15:9; A - 16:10)
-R - reduced blanking
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch makes some small rearrangements of the PCI probing code in
order to make it possible for arch code to set up the PCI tree
without needing to duplicate code from the PCI layer unnecessarily.
PPC64 will use this to set up the PCI tree from the Open Firmware
device tree, which we need to do on logically-partitioned pSeries
systems.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Trivial patch against 2.6.13 to unhide SMBus on Compaq Evo N620c laptop using
Intel 82855PM chipset.
Signed-off-by: Rumen Zarev <rzarev@caltech.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Martin Franc reported that the pciehp driver was not enabling bus
master capability on his hot-plugged card. pciehprm_enable_card()
was updating the PCI command register only if _HPP indicated a
value for SERR or PERR that was different from the current setting.
I don't have hardware that reproduces this problem, but Martin
reports that this patch fixes the problem for him.
Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
From rzarev@its.caltech.edu Tue Sep 6 18:29:50 2005
Date: Tue, 6 Sep 2005 13:39:32 -0700 (PDT)
From: Rumen Ivanov Zarev <rzarev@its.caltech.edu>
Message-Id: <200509062039.j86KdWMr014934@inky.its.caltech.edu>
To: gregkh@suse.de
Subject: PCI: Unhide SMBus on Compaq Evo N620c
Cc: linux-kernel@vger.kernel.org
Trivial patch against 2.6.13 to unhide SMBus on Compaq Evo N620c laptop using
Intel 82855PM chipset.
Signed-off-by: Rumen Zarev <rzarev@caltech.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/pci/quirks.c | 6 ++++++
1 file changed, 6 insertions(+)
--- gregkh-2.6.orig/drivers/pci/quirks.c 2005-09-09 10:28:55.000000000 -0700
+++ gregkh-2.6/drivers/pci/quirks.c 2005-09-09 13:51:44.000000000 -0700
@@ -876,6 +876,12 @@ static void __init asus_hides_smbus_host
case 0xC00C: /* Samsung P35 notebook */
asus_hides_smbus = 1;
}
+ } else if (unlikely(dev->subsystem_vendor == PCI_VENDOR_ID_COMPAQ)) {
+ if (dev->device == PCI_DEVICE_ID_INTEL_82855PM_HB)
+ switch(dev->subsystem_device) {
+ case 0x0058: /* Compaq Evo N620c */
+ asus_hides_smbus = 1;
+ }
}
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82845_HB, asus_hides_smbus_hostbridge );
This patch changes radeon to request only resources 0 and 2 instead of all
3. This works around problems with some setups where BAR 1 (IO BAR) has
not been assigned by the firmware since it's not used on the machine and
the kernel fails to assign something to it due to the card being between a
P2P bridge that was configured without an IO range at all.
This typically fixes radeonfb on some Apple Xserve G5 machines
Signed-off-by: Daniel Burcaw <dburcaw@terrasoftsolutions.com>
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>
This trivial patch gives a performance boost to the framebuffer console
Constructing the bitmaps that are given to the bitblit functions of the
framebuffer drivers is time consuming. Here we avoide a call to the slow
fb_pad_aligned_buffer(). The patch replaces that call with a simple but
much more efficient bytewise copy.
The kernel spends a significant time at this place if you use 8x* fonts.
Every pixel displayed on your screen is prepared here.
Some benchmark results:
Displaying a file of 2000 lines with 160 characters each takes 889 ms
system time using cyblafb on my system (Im using a 1280x1024 video mode,
resulting in a 160x64 character console)
Displaying the same file with the enclosed patch applied to 2.6.13 only
takes 760 ms system time, saving 129 ms or 14.5%.
Font widths other than 8 are not affected.
The advantage and correctness of this patch should be obvious.
Signed-off-by: Knut Petersen <Knut_Petersen@t-online.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is a framebuffer driver for the Cyberblade/i1 graphics core.
Currently tridenfb claims to support the cyberblade/i1 graphics core. This
is of very limited truth. Even vesafb is faster and provides more working
modes and a much better quality of the video signal. There is a great
number of bugs in tridentfb ... but most often it is impossible to decide
if these bugs are real bugs or if fixing them for the cyberblade/i1 core
would break support for one of the other supported chips.
Tridentfb seems to be unmaintained,and documentation for most of the
supported chips is not available. So "fixing" cyberblade/i1 support inside
of tridentfb was not an option, it would have caused numerous
if(CYBERBLADEi1) else ... cases and would have rendered the code to be
almost unmaintainable.
A first version of this driver was published on 2005-07-31. A fix for a
bug reported by Jochen Hein was integrated as well as some changes
requested by Antonino A. Daplas.
A message has been added to tridentfb to inform current users of tridentfb
to switch to cyblafb if the cyberblade/i1 graphics core is detected.
This patch is one logical change, but because of the included documentation
it is bigger than 70kb. Therefore it is not sent to lkml and
linux-fbdev-devel,
Signed-off-by: Knut Petersen <Knut_Petersen@t-online.de>
Cc: Muli Ben-Yehuda <mulix@mulix.org>
Acked-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
err remains uninitialized of pci_request_regions fails.
Found by Thorsten Kukuk, I added a few more checks.
Signed-off-by: Olaf Hering <olh@suse.de>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This lifts sisfb from version 1.7.17 to version 1.8.9. Changes include:
- Added support for XGI V3XT, V5, V8, Z7 chipsets, including POSTing of
all of these chipsets.
- Added support for latest SiS chipsets (761).
- Added support for SiS76x memory "hybrid" mode.
- Added support for new LCD resolutions (eg 1280x854, 856x480).
- Fixed support for 320x240 STN panels (for embedded devices).
- Fixed many HDTV modes (525p, 750p, 1080i).
- Fixed PCI config register reading/writing to use proper kernel
functions for this purpose.
- Fixed PCI ROM handling to use the kernel's proper functions.
- Removed lots of "typedef"s.
- Removed lots of code which was for X.org/XFree86 only.
- Fixed coding style in many places.
- Removed lots of 2.4 cruft.
- Reduced stack size by unifying two previously separate structs into
one.
- Added new hooks for memory allocation (for DRM). Now the driver can
truly handle multiple cards, including memory management.
- Fixed numerous minor bugs.
Signed-off-by: Thomas Winischhofer <thomas@winischhofer.net>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This updates the matroxfb code so that it can find the PInS data embedded
in the BIOS on PowerPC cards. The process for finding the data is
different on OpenFirmware cards than on x86 cards, and the code for doing
so was missing.
After patching, building, installing, and booting a kernel, you should grep
for "PInS" in /var/log/messages. You should see two messages in the log:
PInS data found at offset XXXXX
PInS memtype = X
On the GXT135p card I get "31168" and "5". The first value is irrelevant,
but it's presence lets me know that the PInS data was actually found. On a
GXT130p, the second value should be 3. Since I don't have access to that
hardware, if someone can verify that, I will submit a follow-on patch that
rips out all the memtype parameter stuff.
Signed-off-by: Ian Romanick <idr@us.ibm.com>
Signed-off-by: Petr Vandrovec <vandrove@vc.cvut.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The link for ATI's product page in drivers/video/Kconfig for FB_RADEON is
broken. Replace with a product comparison page.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently, atyfb has code that sets the hsync and vsync polarity based on the
current video mode, without letting the user override the settings.
Remove this particular code. The sync polarities are set by the PROM, the
user or by the videomode.
Signed-off-by: Alexander Kern <alex.kern@gmx.de>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On a vc resize, the contents of the old screen buffer are transferred to the
new screenbuffer. If the new screenbuffer is smaller than the old one, only
the contents from the bottom are copied to new. If the contents of the old
buffer are located at the top, then the contents will not be copied to the new
buffer resulting in a blank screen.
This bug will happen only if the vc in question is not in the foreground.
Doing an fbset -a or con2fbmap will trigger this bug.
To fix this problem, base the start of the copy from the location of the
current cursor. If the cursor is near the top of the buffer, copy the
contents at the top, and if the cursor is near the bottom of the buffer, then
copy the contents at the bottom. In the unlikely case where the new row size
is greater than 2x smaller than the old one, and the cursor is in the middle,
copy 1/2 screenful from the top and bottom of the cursor position.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently, the default linux 16-colors are converted to 4-colors by simply
dividing the values by 4. However, this is not necessarily correct since the
first 4 colors are converted to black, rendering them invisible.
So, for black, no conversion; for light colors, convert to gray, for normal
text color, no conversion, and for bright colors, convert to intense white.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently, fbcon assumes that the visual FB_VISUAL_MONO* is always 1 bit.
According to Geert, there are old hardware where it's possible to have
monochrome at 8-bit, but has only 2 colors, black - 0x00 and white - 0xff.
Fix color handlers (fb_get_color_depth, and get_color) for this special case.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If nvidiafb fails to probe the EDID block, get the EDID from the BIOS.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Fallback to firmware EDID if chipset has no DDC/I2C support or if I2C
probing failed
- Add fb_blank hook
- Fix savagefb_suspend/resume to enable driver to successfully suspend and
resume from S3, memory or disk
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
For the i386, code is already present in video.S that gets the EDID from the
video BIOS. Make this visible so drivers can also use this data as fallback
when i2c does not work.
To ensure that the EDID block is returned for the primary graphics adapter
only, by check if the IORESOURCE_ROM_SHADOW flag is set.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Geode framebuffer driver updates:
- Local mode list (taken from modedb.c) containing only relevant modes.
This also makes the driver work as a module.
- Make it a PCI driver (from James Simmons <jsimmons@infradead.org>).
- A few other minor cosmetic bits and pieces.
Signed-off-by: David Vrabel <dvrabel@arcom.com>
Signed-off-by: James Simmons <jsimmons@infradead.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes drivers that have hardware cursors from calling the
software cursor code. Also if the driver sets a no hardware cursor flag
then the driver reports a error it someone attempts to use the cursor.
Signed-off-by: James Simmons <jsimmons@infradead.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add rudimentary support by manipulating the VGA registers. However, not
all vesa modes are VGA compatible, so VGA compatiblity is checked first.
Only 2 levels are supported, powerup and powerdown.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add capability to fbdev to listen to the FB_ACTIVATE_ALL flag. If set, it
notifies fbcon that all consoles must be set to the current var.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch attempts to do a better job of cleaning up after detecting errors
on the transport. This should also improve error reporting on broken
connections to servers.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
LANL reported some issues with random crashes during mount of legacy protocol
servers (9P2000 versus 9P2000.u) -- crash was always happening in readlink
(which should never happen in legacy mode). Added some sanity conditionals to
the get_inode code which should prevent the errors LANL was seeing. Code
tested benign through regression.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Cleanup code in v9fs vfs_inode as suggested by Alexey Dobriyan. Did some
major revamping of the v9fs setattr code to remove unnecessary allocations and
clean up some dead-code.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change magic error numbers to system defined constants in v9fs error.h As
suggested by Jan-Benedict Glaw.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains debug and other misc routines.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Support for force umount
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains transport routines.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains the 9P protocol functions.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains VFS superblock and mapping code.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains the VFS inode interfaces.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains the VFS file, dentry & directory interfaces.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
OVERVIEW
V9FS is a distributed file system for Linux which provides an
implementation of the Plan 9 resource sharing protocol 9P. It can be
used to share all sorts of resources: static files, synthetic file servers
(such as /proc or /sys), devices, and application file servers (such as
FUSE).
BACKGROUND
Plan 9 (http://plan9.bell-labs.com/plan9) is a research operating
system and associated applications suite developed by the Computing
Science Research Center of AT&T Bell Laboratories (now a part of
Lucent Technologies), the same group that developed UNIX , C, and C++.
Plan 9 was initially released in 1993 to universities, and then made
generally available in 1995. Its core operating systems code laid the
foundation for the Inferno Operating System released as a product by
Lucent Bell-Labs in 1997. The Inferno venture was the only commercial
embodiment of Plan 9 and is currently maintained as a product by Vita
Nuova (http://www.vitanuova.com). After updated releases in 2000 and
2002, Plan 9 was open-sourced under the OSI approved Lucent Public
License in 2003.
The Plan 9 project was started by Ken Thompson and Rob Pike in 1985.
Their intent was to explore potential solutions to some of the
shortcomings of UNIX in the face of the widespread use of high-speed
networks to connect machines. In UNIX, networking was an afterthought
and UNIX clusters became little more than a network of stand-alone
systems. Plan 9 was designed from first principles as a seamless
distributed system with integrated secure network resource sharing.
Applications and services were architected in such a way as to allow
for implicit distribution across a cluster of systems. Configuring an
environment to use remote application components or services in place
of their local equivalent could be achieved with a few simple command
line instructions. For the most part, application implementations
operated independent of the location of their actual resources.
Commercial operating systems haven't changed much in the 20 years
since Plan 9 was conceived. Network and distributed systems support is
provided by a patchwork of middle-ware, with an endless number of
packages supplying pieces of the puzzle. Matters are complicated by
the use of different complicated protocols for individual services,
and separate implementations for kernel and application resources.
The V9FS project (http://v9fs.sourceforge.net) is an attempt to bring
Plan 9's unified approach to resource sharing to Linux and other
operating systems via support for the 9P2000 resource sharing
protocol.
V9FS HISTORY
V9FS was originally developed by Ron Minnich and Maya Gokhale at Los
Alamos National Labs (LANL) in 1997. In November of 2001, Greg Watson
setup a SourceForge project as a public repository for the code which
supported the Linux 2.4 kernel.
About a year ago, I picked up the initial attempt Ron Minnich had
made to provide 2.6 support and got the code integrated into a 2.6.5
kernel. I then went through a line-for-line re-write attempting to
clean-up the code while more closely following the Linux Kernel style
guidelines. I co-authored a paper with Ron Minnich on the V9FS Linux
support including performance comparisons to NFSv3 using Bonnie and
PostMark - this paper appeared at the USENIX/FREENIX 2005
conference in April 2005:
( http://www.usenix.org/events/usenix05/tech/freenix/hensbergen.html ).
CALL FOR PARTICIPATION/REQUEST FOR COMMENTS
Our 2.6 kernel support is stabilizing and we'd like to begin pursuing
its integration into the official kernel tree. We would appreciate any
review, comments, critiques, and additions from this community and are
actively seeking people to join our project and help us produce
something that would be acceptable and useful to the Linux community.
STATUS
The code is reasonably stable, although there are no doubt corner cases
our regression tests haven't discovered yet. It is in regular use by several
of the developers and has been tested on x86 and PowerPC
(32-bit and 64-bit) in both small and large (LANL cluster) deployments.
Our current regression tests include fsx, bonnie, and postmark.
It was our intention to keep things as simple as possible for this
release -- trying to focus on correctness within the core of the
protocol support versus a rich set of features. For example: a more
complete security model and cache layer are in the road map, but
excluded from this release. Additionally, we have removed support for
mmap operations at Al Viro's request.
PERFORMANCE
Detailed performance numbers and analysis are included in the FREENIX
paper, but we show comparable performance to NFSv3 for large file
operations based on the Bonnie benchmark, and superior performance for
many small file operations based on the PostMark benchmark. Somewhat
preliminary graphs (from the FREENIX paper) are available
(http://v9fs.sourceforge.net/perf/index.html).
RESOURCES
The source code is available in a few different forms:
tarballs: http://v9fs.sf.net
CVSweb: http://cvs.sourceforge.net/viewcvs.py/v9fs/linux-9p/
CVS: :pserver:anonymous@cvs.sourceforge.net:/cvsroot/v9fs/linux-9p
Git: rsync://v9fs.graverobber.org/v9fs (webgit: http://v9fs.graverobber.org)
9P: tcp!v9fs.graverobber.org!6564
The user-level server is available from either the Plan 9 distribution
or from http://v9fs.sf.net
Other support applications are still being developed, but preliminary
version can be downloaded from sourceforge.
Documentation on the protocol has historically been the Plan 9 Man
pages (http://plan9.bell-labs.com/sys/man/5/INDEX.html), but there is
an effort under way to write a more complete Internet-Draft style
specification (http://v9fs.sf.net/rfc).
There are a couple of mailing lists supporting v9fs, but the most used
is v9fs-developer@lists.sourceforge.net -- please direct/cc your
comments there so the other v9fs contibutors can participate in the
conversation. There is also an IRC channel: irc://freenode.net/#v9fs
This part of the patch contains Documentation, Makefiles, and configuration
file changes.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With the use of RCU in files structure, the look-up of files using fds can now
be lock-free. The lookup is protected by rcu_read_lock()/rcu_read_unlock().
This patch changes the readers to use lock-free lookup.
Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Ravikiran Thirumalai <kiran_th@gmail.com>
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Rusty Russell