The commit b5810039a5 contains the note
A last caveat: the ZERO_PAGE is now refcounted and managed with rmap
(and thus mapcounted and count towards shared rss). These writes to
the struct page could cause excessive cacheline bouncing on big
systems. There are a number of ways this could be addressed if it is
an issue.
And indeed this cacheline bouncing has shown up on large SGI systems.
There was a situation where an Altix system was essentially livelocked
tearing down ZERO_PAGE pagetables when an HPC app aborted during startup.
This situation can be avoided in userspace, but it does highlight the
potential scalability problem with refcounting ZERO_PAGE, and corner
cases where it can really hurt (we don't want the system to livelock!).
There are several broad ways to fix this problem:
1. add back some special casing to avoid refcounting ZERO_PAGE
2. per-node or per-cpu ZERO_PAGES
3. remove the ZERO_PAGE completely
I will argue for 3. The others should also fix the problem, but they
result in more complex code than does 3, with little or no real benefit
that I can see.
Why? Inserting a ZERO_PAGE for anonymous read faults appears to be a
false optimisation: if an application is performance critical, it would
not be doing many read faults of new memory, or at least it could be
expected to write to that memory soon afterwards. If cache or memory use
is critical, it should not be working with a significant number of
ZERO_PAGEs anyway (a more compact representation of zeroes should be
used).
As a sanity check -- mesuring on my desktop system, there are never many
mappings to the ZERO_PAGE (eg. 2 or 3), thus memory usage here should not
increase much without it.
When running a make -j4 kernel compile on my dual core system, there are
about 1,000 mappings to the ZERO_PAGE created per second, but about 1,000
ZERO_PAGE COW faults per second (less than 1 ZERO_PAGE mapping per second
is torn down without being COWed). So removing ZERO_PAGE will save 1,000
page faults per second when running kbuild, while keeping it only saves
less than 1 page clearing operation per second. 1 page clear is cheaper
than a thousand faults, presumably, so there isn't an obvious loss.
Neither the logical argument nor these basic tests give a guarantee of no
regressions. However, this is a reasonable opportunity to try to remove
the ZERO_PAGE from the pagefault path. If it is found to cause regressions,
we can reintroduce it and just avoid refcounting it.
The /dev/zero ZERO_PAGE usage and TLB tricks also get nuked. I don't see
much use to them except on benchmarks. All other users of ZERO_PAGE are
converted just to use ZERO_PAGE(0) for simplicity. We can look at
replacing them all and maybe ripping out ZERO_PAGE completely when we are
more satisfied with this solution.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus "snif" Torvalds <torvalds@linux-foundation.org>
0x1106, 0x7204 is unknown and thus is not an IGP/GPU.
0x1106, 0x3304 is K8M800 hostbridge, not an IGP/GPU.
None of them are in drm git tree.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This makes sure each blit starts as early as possible, which may improve
texture upload performance in some cases.
Signed-off-by: Dave Airlie <airlied@redhat.com>
The data is now in kernel space, copied in/out as appropriate according to t
This results in DRM_COPY_{TO,FROM}_USER going away, and error paths to deal
with those failures. This also means that XFree86 4.2.0 support for i810 DR
is lost.
Signed-off-by: Dave Airlie <airlied@linux.ie>
As a fallout, replace filp storage with file_priv storage for "unique
identifier of a client" all over the DRM. There is a 1:1 mapping, so this
should be a noop. This could be a minor performance improvement, as everyth
on Linux dereferenced filp to get file_priv anyway, while only the mmap ioct
went the other direction.
Signed-off-by: Dave Airlie <airlied@linux.ie>
This was used to make all ioctl handlers return -errno on linux and errno on
*BSD. Instead, just return -errno in shared code, and flip sign on return f
shared code to *BSD code.
Signed-off-by: Dave Airlie <airlied@linux.ie>
Coverity spotted a "use after free" bug in
drivers/char/agp/amd-k7-agp.c::amd_create_gatt_pages().
The problem is this:
If "entry = kzalloc(sizeof(struct amd_page_map), GFP_KERNEL);"
fails, then there's a loop in the function to free all entries
allocated so far and break out of the allocation loop. That in itself
is pretty sane, but then the (now freed) 'tables' is assigned to
amd_irongate_private.gatt_pages and 'retval' is set to -ENOMEM which
causes amd_free_gatt_pages(); to be called at the end of the function.
The problem with this is that amd_free_gatt_pages() will then loop
'amd_irongate_private.num_tables' times and try to free each entry in
tables[] - this is bad since tables has already been freed and
furthermore it will call kfree(tables) at the end - a double free.
This patch removes the freeing loop in amd_create_gatt_pages() and
instead relies entirely on the call to amd_free_gatt_pages() to free
everything we allocated in case of an error. It also sets
amd_irongate_private.num_tables to the actual number of entries
allocated instead of just using the value passed in from the caller -
this ensures that amd_free_gatt_pages() will only attempt to free
stuff that was actually allocated.
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
With Andi's clflush fixup, we were getting hangs on server exit, flushing the
mappings after freeing each page helped.
This showed up a race condition where the pages after being freed could be
reused before the agp mappings had been flushed. Flushing after each single
page is a bad thing for future drm work, so make the page destroy a two pass
unmapping all the pages, flushing the mappings, and then destroying the pages.
Signed-off-by: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
deal with signedness of the stuff passed to set_bit() et.al.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert from class_device to device in drivers/char.
Signed-off-by: Tony Jones <tonyj@suse.de>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
struct cdev does not need the kobject name to be set, as it is never
used. This patch fixes up the few places it is set.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Now we will only have entries in the device tree for the actual existing
devices (including their OS/400 properties). This way viotape.c gets
all the information about the devices from the device tree.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
It was only being used to carry around dma_iommu_ops and vio_iommu_table
which we can use directly instead. This also means that vio_bus_device
doesn't need to refer to them either.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Three main sets of changes:
1) dmi_get_system_info() return value should have been marked const,
since callers should not be changing that data.
2) const-ify DMI internals, since DMI firmware tables should,
whenever possible, be marked const to ensure we never ever write to
that data area.
3) const-ify DMI API, to enable marking tables const where possible
in low-level drivers.
And if we're really lucky, this might enable some additional
optimizations on the part of the compiler.
The bulk of the changes are #2 and #3, which are interrelated. #1 could
have been a separate patch, but it was so small compared to the others,
it was easier to roll it into this changeset.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
When building a custom keymap, after setting GENERATE_KEYMAP := 1 in
drivers/char/Makefile, the kernel build fails like this:
CC drivers/char/vt.o
make[2]: *** No rule to make target `drivers/char/%.map', needed by `drivers/char/defkeymap.c'. Stop.
make[1]: *** [drivers/char] Error 2
make: *** [drivers] Error 2
This was caused by commit af8b128719, which
deleted a necessary colon from the Makefile rule that generates the keymap,
since that rule contains both a target and a target-pattern. The following
patch puts the colon back:
Signed-off-by: Maarten Bressers <mbres@gentoo.org>
Cc: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should generally prefer to return ERESTARTNOHAND rather than EINTR,
so that processes with unhandled signals that get ignored don't return
EINTR.
This can help with X startup issues:
Fatal server error:
xf86OpenConsole: VT_WAITACTIVE failed: Interrupted system call
although the real fix is having the X server always retry EINTR
regardless (since EINTR does happen for signals that have handlers
installed). Keithp has a patch for that.
Regardless, ERESTARTNOHAND is the correct thing to use.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit f443675aff, which
breaks horribly if you aren't running an unreleased xf86-video-intel
driver out of git.
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Zhenyu Wang <zhenyu.z.wang@intel.com>
Acked-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
TCP V4 sequence numbers are 32bits, and RFC 793 assumed a 250 KHz clock.
In order to follow network speed increase, we can use a faster clock, but
we should limit this clock so that the delay between two rollovers is
greater than MSL (TCP Maximum Segment Lifetime : 2 minutes)
Choosing a 64 nsec clock should be OK, since the rollovers occur every
274 seconds.
Problem spotted by Denys Fedoryshchenko
[ This bug was introduced by f859581519 ]
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When calling the RELDISP VT ioctl, we are reading vt_newvt while the
console workqueue could be messing with it (through change_console()). We
fix this race by taking the console semaphore before reading vt_newvt.
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
Acked-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The new behaviour of CFS exposes a race which occurs if a switch is
requested when vt_mode.mode is VT_PROCESS.
The process with vc->vt_pid is signaled before vc->vt_newvt is set.
This causes the switch to fail when triggered by the monitoing process
because the target is still -1.
[ If the signal sending fails, the subsequent "reset_vc(vc)" will then
reset vt_newvt to -1, so this works for that case too. - Linus ]
Signed-off-by: Jan Lübbe <jluebbe@lasnet.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This code is ported from the DRM git tree and allows the vblank interrupts
to function on the i965 hw. It also requires a change in Mesa's 965 driver
to actually use them.
[ Without this patch, my 965GM drops vblank interrupts - Jesse ]
Signed-off-by: Dave Airlie <airlied@linux.ie>
Acked-by: Jesse Barnes <jesse.barnes@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Following patch silents;
...
drivers/char/hpet.c:72: warning: 'clocksource_hpet' defined but not used
drivers/char/hpet.c:81: warning: 'hpet_clocksource' defined but not used
...
build warnings on i386, they appeared after commit 3b2b64fd31
Signed-off-by: S.Çağlar Onur <caglar@pardus.org.tr>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
--
drivers/char/hpet.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)
If hpet has been initialized before registering hpet driver, the callback
function of hpet_resources will return the status code of -EBUSY, which is
not defined in the ACPI exception table. So when ACPI checks the status
code of callback function, it will report the unknown exception code.
So the status code in ACPI is used instead of the generic error code in the
ACPI callback function of hpet_resources.
For example: -EBUSY is replaced by AE_ALREADY_EXISTS
-EINVAL is replaced by AE_NO_MEMORY
http://bugzilla.kernel.org/show_bug.cgi?id=8630
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
The vma_data structure may be shared by vma's from multiple tasks, with no
way of knowing which areas are shared or not shared, so release/clear pages
only when the refcount (of vma's) goes to zero.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The mask on i830 should be 0x70 always, later chips 0xF0 should be okay.
Signed-off-by: Dave Airlie <airlied@linux.ie>
Acked-by: Zhenyu Wang <zhenyu.z.wang@intel.com>
Cc: Michael Haas <laga@laga.ath.cx>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a couple drivers that do not correctly terminate their pci_device_id
lists. This results in garbage being spewed into modules.pcimap when the
module happens to not have 28 NULL bytes following the table, and/or the
last PCI ID is actually truncated from the table when calculating the
modules.alias PCI aliases, cause those unfortunate device IDs to not
auto-load.
Signed-off-by: Kees Cook <kees@ubuntu.com>
Acked-by: Corey Minyard <minyard@acm.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Acked-by: Jeff Garzik <jeff@garzik.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The shrinking of a virtual memory area that is mmap(2)'d to a memory
special file (device drivers/char/mspec.c) can cause a panic.
If the mapped size of the vma (vm_area_struct) is very large, mspec allocates
a large vma_data structure with vmalloc(). But such a vma can be shrunk by
an munmap(2). The current driver uses the current size of each vma to
deduce whether its vma_data structure was allocated by kmalloc() or vmalloc().
So if the vma was shrunk it appears to have been allocated by kmalloc(),
and mspec attempts to free it with kfree(). This results in a panic.
This patch avoids the panic (by preserving the type of the allocation) and
also makes mspec work correctly as the vma is split into pieces by the
munmap(2)'s.
All vma's derived from such a split vma share the same vma_data structure that
represents all the pages mapped into this set of vma's. The mpec driver
must be made capable of using the right portion of the structure for each
member vma. In other words, it must index into the array of page addresses
using the portion of the array that represents the current vma. This is
enabled by storing the vma group's vm_start in the vma_data structure.
The shared vma_data's are not protected by mm->mmap_sem in the fork() case
so the reference count is left as atomic_t.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Acked-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add Guards around TIOCSLCKTRMIOS and TIOCGLCKTRMIOS.
Several architectures are still broken. Put temporary-for-2.6.23 ifdef guards
around the offending code.
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by:: Linus Torvalds <torvalds@linux-foundation.org>
G33 has 1MB GTT table range. Fix GTT mapping in case like 512MB aperture
size.
Signed-off-by: Zhenyu Wang <zhenyu.z.wang@intel.com>
Acked-by: Dave Airlie <airlied@linux.ie>
Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
G33 GTT stolen memory is below graphics data stolen memory and be seperate,
so don't subtract it in stolen mem counting.
Signed-off-by: Zhenyu Wang <zhenyu.z.wang@intel.com>
Acked-by: Dave Airlie <airlied@linux.ie>
Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I ran into a few problems.
n_tty_ioctl() for instance:
drivers/char/tty_ioctl.c:799: error: $,1rxstruct termios$,1ry has no
member named $,1rxc_ispeed$,1ry
This is calling the copy interface that is supposed to be using
a termios2 when the new interfaces are defined, however:
case TIOCGLCKTRMIOS:
if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios_locked))
return -EFAULT;
return 0;
This is going to write over the end of the userspace
structure by a few bytes, and wasn't caught by you yet
because the i386 implementation is simply copy_to_user()
which does zero type checking.
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that ec3104 board support has been removed nothing references
this driver so it can be safely removed as well.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
The HPET clocksource in drivers/char/hpet.c was written as generic code
for ia64, but it is not yet ready to replace the native HPET clocksource
implementations that the i386/x86-64 architectures use.
On x86[-64], trying to register this clocksource results in potentially
multiple hpet-based clocksources being registered, and if the ia64 one
is chosen on x86_64 some users have experienced hangs.
Eventually all three architectures may end up using the same code, but
that is not the case right now.
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Paolo Ornati <ornati@fastwebnet.it>
Cc: Bob Picco <bob.picco@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
patchset against 2.6.23-rc3.
corrects missing ioremap return checks and balancing on iounmap calls, integrated changes per list
recommendations on the original set of patches..
Signed-off-by: Scott Thompson <postfail <at> hushmail.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
kmalloc() hands us a void pointer, we don't need to cast it.
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Schedule /proc/acpi/event for removal in 6 months.
Re-name acpi_bus_generate_event() to acpi_bus_generate_proc_event()
to make sure there is no confusion that it is for /proc/acpi/event only.
Add CONFIG_ACPI_PROC_EVENT to allow removal of /proc/acpi/event.
There is no functional change if CONFIG_ACPI_PROC_EVENT=y
Signed-off-by: Len Brown <len.brown@intel.com>
Get module reference on open() by generic HDLC to prevent module from
unloading while interface is active.
Signed-off-by: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
m68k/mac: Make mac_hid_mouse_emulate_buttons() declaration visible
drivers/char/keyboard.c: In function 'kbd_keycode':
drivers/char/keyboard.c:1142: error: implicit declaration of function 'mac_hid_mouse_emulate_buttons'
The forward declaration of mac_hid_mouse_emulate_buttons() is not visible on
m68k because it's hidden in the middle of a big #ifdef block.
Move it to <linux/kbd_kern.h>, correct the type of the second parameter, and
include <linux/kbd_kern.h> where needed.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix up the maintainers info in the tpm drivers. Kylene will be out for
some time, so copying the sourceforge list is the best way to get some
attention.
Cc: Marcel Selhorst <tpm@selhorst.net>
Cc: Kylene Jo Hall <kjhall@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
get_property has been renamed to of_get_property.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Nick Piggin