Alan Cox [Tue, 10 Jan 2006 04:54:13 +0000 (20:54 -0800)]
[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>
Paul Jackson [Tue, 10 Jan 2006 04:54:08 +0000 (20:54 -0800)]
[PATCH] Serial: disable jsm in ppc64 defconfig
Changes to the serial driver to remove flip buffers have broken the serial
jsm driver. It doesn't even compile anymore. The jsm driver was enabled
in only one defconfig - ppc64. In order to keep defconfigs building,
disable CONFIG_SERIAL_JSM for the time being.
Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Adrian Bunk [Tue, 10 Jan 2006 04:54:06 +0000 (20:54 -0800)]
[PATCH] fs/ext3/: small cleanups
This patch contains the following cleanups:
- there's no need for ext3_count_free() #ifndef EXT3FS_DEBUG
- having prototypes for ext3_count_free() in two different headers is
nonsense
Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Adrian Bunk [Tue, 10 Jan 2006 04:54:04 +0000 (20:54 -0800)]
[PATCH] drivers/video/: possible cleanups
This patch contains the possible cleanups including the following:
- every file should #include the headers containing the prototypes for
it's global functions
- make needlessly global functions static
- kyro/STG4000Interface.h: #include video/kyro.h and linux/pci.h
instead of a manual "struct pci_dev"
- i810_main.{c,h}: prototypes for static functions belong to the
C file
Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: "Antonino A. Daplas" <adaplas@hotpop.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Jesper Juhl [Tue, 10 Jan 2006 04:54:01 +0000 (20:54 -0800)]
[PATCH] turn "const static" into "static const"
ICC likes to complain about storage class not being first, GCC doesn't
care much (except for cases like "inline static").
have a hard time seeing how it could break anything.
Thanks to Gabriel A. Devenyi for pointing out
http://linuxicc.sourceforge.net/ which is what made me create this patch.
Martin Waitz [Tue, 10 Jan 2006 04:53:55 +0000 (20:53 -0800)]
[PATCH] DocBook: warn for missing macro parameters
Previously kernel-doc silently ignored missing parameter descriptions for
preprocessor macros. Now that all such omissions are fixed up we can warn
about them in kernel-doc to be able to keep it that way.
Signed-off-by: Martin Waitz <tali@admingilde.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Ville Syrjala [Tue, 10 Jan 2006 04:53:49 +0000 (20:53 -0800)]
[PATCH] Fix console blanking
Current console blanking code is broken. It will first do a normal blank,
then start the VESA blank timer if vesa_off_interval != 0, and then proceed
to do the VESA blanking directly. After the timer expires it will do the
VESA blanking a second time. Also the vesa_powerdown() function doesn't
allow all VESA modes to be used.
With this patch the behaviour is:
1. Blank: vesa_off_interval != 0 -> Do normal blank
vesa_off_interval == 0 -> Do VESA blank
2. Start the VESA blank timer if vesa_off_interval != 0 and
vesa_power_mode != 0.
It also gets rid of the limiting vesa_powerdown() function.
Signed-off-by: Ville Syrjala <syrjala@sci.fi> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Thomas Koeller [Tue, 10 Jan 2006 04:53:48 +0000 (20:53 -0800)]
[PATCH] non-linear frame buffer read/write access
While the code in fbmem.c allows for hooking read/write access to
non-linear frame buffers by means of fb_read and fb_write in struct fb_ops,
I could not find a way tho access the actual frame buffer memory from
within these routines. I therefore had to patch fbmem.c, to be able to
retrieve a pointer to struct fb_info from the 'file' argument to these
functions.
The second hunk of the patch is not strictly required, I only did that for
symmetry reasons (and the code is somewhat shorter).
Signed-off-by: Thomas Koeller <thomas@koeller.dyndns.org> Acked-by: "Antonino A. Daplas" <adaplas@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- replace kmalloc with kzalloc
- remove repeated define (FONTCHHCNT)
- remove unneeded local variable (redraw) in ypan_{up|down}_redraw
- add and delete cursor timer in fbcon_switch() if old_info != info
Arnaud Patard [Tue, 10 Jan 2006 04:53:41 +0000 (20:53 -0800)]
[PATCH] s3c2410fb: cleanup and fix
Here are some cleanups for the s3c2410fb drivers. It :
* Removes a buggy call to s3c2410fb_init_registers. There was two calls
to this function but the first was done without all initialisations
done. No oops but it may confuse some LCDs.
* Makes two functions static.
[PATCH] fbdev: Fix return code of fb_read and fb_write
Make fb_read() and fb_write() return 0 (EOF) instead of -ENOSPC if reading at
or past the end of the framebuffer. This fixes user space apps hanging if
info->fix.smem_len == 0.
Knut Petersen [Tue, 10 Jan 2006 04:53:36 +0000 (20:53 -0800)]
[PATCH] fbcon: disable ywrap if not supported by fbcon scrolling code
updatescrollmode() must not select ywrap scrolling if
divides(vc->vc_font.height, yres) is not true as this is not supported by
the actual ywrap scrolling code.
The bug is triggered with e.g. mode 800x600, vxres 1024, vyres 8192, bpp
8, font dimensions 8x16, 8Mb video ram and FBINFO_HWACCEL_YWRAP set. If
those conditions are met, scrolling is broken and garbage is permanently
displayed at the bottom of the screen.
No regression, no possible side effects.
Definitely needed by cyblafb and probably needed by amifb.
Ville Syrjälä [Tue, 10 Jan 2006 04:53:32 +0000 (20:53 -0800)]
[PATCH] atyfb: LT/LG cleanup
Clean up LT and LG chip descriptions.
"Mach64 LG" is called 3D Rage LT in the specs and ATI press releases.
"Mach64 LT" is unclear. XFree86 driver doesn't know this chip at all.
Windows display.inf calls it just "mach64 LT" and it uses the same driver as
VT-A/GT-A and older chips. VT-B/GT-B and better use another driver and all of
those chips have a more descriptive name in the display.inf file. That makes
me think this chip is not a 3D Rage chip.
Signed-off-by: Ville Syrjälä <syrjala@sci.fi> Signed-off-by: Antonino Daplas <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- remove unneeded casts
- make setcolreg return success if regno > 15, but don't do anything
- use framebuffer_alloc/framebuffer_release to allocate/free memory
Jean Delvare [Tue, 10 Jan 2006 04:52:59 +0000 (20:52 -0800)]
[PATCH] savagefb: One more I2C-enabled device in savagefb
The I2C bus of the S3 Savage2000 is supposed to work the same way the Savage4
does. At least, the legacy i2c-savage4 driver handled both devices the same
way.
I do not have the hardware to test this, so testers are welcome.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Antonino Daplas <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
"After resuming from S3 (suspended while in X), the LCD panel stays black .
However, the laptop is up again, and I can SSH into it from another
machine.
I can get the panel working again, when I first direct video output to the
CRT output of the laptop, and then back to LCD (done by repeatedly hitting
Fn+F5 buttons on the Toshiba, which directs output to either LCD, CRT or
TV) None of this ever happened with older kernels."
This bug is due to the recently added vesafb_blank() method in vesafb. It
works with CRT displays, but has a high incidence of problems in laptop
users. Since CRT users don't really get that much benefit from hardware
blanking, drop support for this.
Oleg Drokin [Tue, 10 Jan 2006 04:52:51 +0000 (20:52 -0800)]
[PATCH] d_instantiate_unique / NFS inode leakage
If we have found aliased dentry that we return, inode reference is not
dropped and inode is not attached anywhere, so it seems the reference to
inode is leaked in that case.
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>, Cc: <viro@parcelfarce.linux.theplanet.co.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch (against 2.6.15-rc5-mm3) fixes a kprobes build break
due to changes introduced in the kprobe locking in 2.6.15-rc5-mm3. In
addition, the patch reverts back the open-coding of kprobe_mutex.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Acked-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently arch_remove_kprobes() is only implemented/required for x86_64 and
powerpc. All other architecture like IA64, i386 and sparc64 implementes a
dummy function which is being called from arch independent kprobes.c file.
This patch removes the dummy functions and replaces it with
#define arch_remove_kprobe(p, s) do { } while(0)
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] kprobes: changed from using spinlock to mutex
Since Kprobes runtime exception handlers is now lock free as this code path is
now using RCU to walk through the list, there is no need for the
register/unregister{_kprobe} to use spin_{lock/unlock}_isr{save/restore}. The
serialization during registration/unregistration is now possible using just a
mutex.
In the above process, this patch also fixes a minor memory leak for x86_64 and
powerpc.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The arch specific kprobes.h files never gets included when CONFIG_KPROBES is
turned off. Hence check for CONFIG_KPROBES is not appropriate here in this
arch specific kprobes.h files.
Also the below defined function kprobes_exception_notify() is not needed when
CONFIG_KPROBES is off.
Compile tested for both CONFIG_KPROBES=y and N.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Matt Helsley [Tue, 10 Jan 2006 04:52:40 +0000 (20:52 -0800)]
[PATCH] Switch getnstimestamp() calls to ktime_get_ts()
Use ktime_get_ts() to take the timestamp instead of getnstimestamp(). This
patch prepares to remove getnstimestamp() by switching its only user to a
different function with almost exactly the same code.
Signed-off-by: Matt Helsley <matthltc@us.ibm.com> Cc: john stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Matt Helsley [Tue, 10 Jan 2006 04:52:39 +0000 (20:52 -0800)]
[PATCH] Export ktime_get_ts()
This series removes the getnstimestamp() function from kernel/time.c in favor
of kernel/hrtimer.c's ktime_get_ts() function which currently does exactly the
same thing: retrieves a high-resolution (ns) timespec structure and performs
the wall_to_monotonic adjustment.
This patch:
Export ktime_get_ts() to be used as a timestamp function since it uses
getnstimefoday() and does the wall_to_monotonic adjustment.
Signed-off-by: Matt Helsley <matthltc@us.ibm.com> Cc: john stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
projects / mirror_ubuntu-eoan-kernel.git / log