aboutsummaryrefslogtreecommitdiff
path: root/drivers/char
AgeCommit message (Collapse)Author
2007-10-15Merge branch 'agp-patches' of ↵Linus Torvalds
master.kernel.org:/pub/scm/linux/kernel/git/airlied/agp-2.6 * 'agp-patches' of master.kernel.org:/pub/scm/linux/kernel/git/airlied/agp-2.6: fix use after free in amd create gatt pages AGP fix race condition between unmapping and freeing pages
2007-10-15via invalid device ids removalXavier Bachelot
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>
2007-10-15radeon: Commit the ring after each partial texture upload blit.chaohong guo
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>
2007-10-15i915: fix vbl swap allocation size.Dave Airlie
Oops... Signed-off-by: Dave Airlie <airlied@linux.ie>
2007-10-15drm: Replace DRM_IOCTL_ARGS with (dev, data, file_priv) and remove DRM_DEVICE.Eric Anholt
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>
2007-10-15drm: remove XFREE86_VERSION macros.Dave Airlie
These are no longer needed or being used. Signed-off-by: Dave Airlie <airlied@redhat.com>
2007-10-15drm: Replace filp in ioctl arguments with drm_file *file_priv.Eric Anholt
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>
2007-10-15drm: Remove DRM_ERR OS macro.Eric Anholt
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>
2007-10-15fix use after free in amd create gatt pagesJesper Juhl
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>
2007-10-15AGP fix race condition between unmapping and freeing pagesDave Airlie
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>
2007-10-14signedness: module_param_array nump argumentAl Viro
... should be unsigned int Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-14long vs. unsigned long - low-hanging fruits in driversAl Viro
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>
2007-10-14synclink_gt endianness annotationsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-14mpc5200_wdt: __user annotationsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-12PTY: add kernel parameter to overwrite legacy pty countKay Sievers
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12Convert from class_device to device in drivers/chartonyj@suse.de
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>
2007-10-12cdev: remove unneeded setting of cdev namesGreg Kroah-Hartman
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>
2007-10-11Merge branch 'master' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc * 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (408 commits) [POWERPC] Add memchr() to the bootwrapper [POWERPC] Implement logging of unhandled signals [POWERPC] Add legacy serial support for OPB with flattened device tree [POWERPC] Use 1TB segments [POWERPC] XilinxFB: Allow fixed framebuffer base address [POWERPC] XilinxFB: Add support for custom screen resolution [POWERPC] XilinxFB: Use pdata to pass around framebuffer parameters [POWERPC] PCI: Add 64-bit physical address support to setup_indirect_pci [POWERPC] 4xx: Kilauea defconfig file [POWERPC] 4xx: Kilauea DTS [POWERPC] 4xx: Add AMCC Kilauea eval board support to platforms/40x [POWERPC] 4xx: Add AMCC 405EX support to cputable.c [POWERPC] Adjust TASK_SIZE on ppc32 systems to 3GB that are capable [POWERPC] Use PAGE_OFFSET to tell if an address is user/kernel in SW TLB handlers [POWERPC] 85xx: Enable FP emulation in MPC8560 ADS defconfig [POWERPC] 85xx: Killed <asm/mpc85xx.h> [POWERPC] 85xx: Add cpm nodes for 8541/8555 CDS [POWERPC] 85xx: Convert mpc8560ads to the new CPM binding. [POWERPC] mpc8272ads: Remove muram from the CPM reg property. [POWERPC] Make clockevents work on PPC601 processors ... Fixed up conflict in Documentation/powerpc/booting-without-of.txt manually.
2007-10-11[POWERPC] iSeries: Move detection of virtual tapesStephen Rothwell
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>
2007-10-11[POWERPC] Remove iSeries_vio_devStephen Rothwell
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>
2007-10-09drivers/firmware: const-ify DMI API and internalsJeff Garzik
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>
2007-10-08Correct Makefile rule for generating custom keymapMaarten Bressers
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 af8b128719f5248e542036ea994610a29d0642a6, 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>
2007-10-07VT_WAITACTIVE: Avoid returning EINTR when not necessaryLinus Torvalds
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>
2007-10-06Revert "intel_agp: fix stolen mem range on G33"Kyle McMartin
This reverts commit f443675affe3f16dd428e46f0f7fd3f4d703eeab, 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>
2007-10-03Merge branch 'linux-2.6' into for-2.6.24Paul Mackerras
2007-10-01[TCP]: secure_tcp_sequence_number() should not use a too fast clockEric Dumazet
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 f85958151900f9d30fa5ff941b0ce71eaa45a7de ] Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-01VT ioctl race fixSamuel Ortiz
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>
2007-09-29fix console change race exposed by CFSJan Lübbe
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>
2007-09-27i915: make vbl interrupts work properly on i965g/gm hw.Dave Airlie
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>
2007-09-26Silent drivers/char/hpet.c build warnings on i386S.Çağlar Onur
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 3b2b64fd311c92f2137eb7cee7025794cd854057 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(-)
2007-09-26Merge branch 'release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: ACPI: hpet: ACPI Error (utglobal-0126): Unknown exception code: 0xFFFFFFF0 ACPI: CONFIG_ACPI_SLEEP=n power off regression in 2.6.23-rc8 (NOT in rc7) ACPI: suspend: build-fix for CONFIG_SUSPEND=n and CONFIG_HIBERNATION=y
2007-09-25ACPI: hpet: ACPI Error (utglobal-0126): Unknown exception code: 0xFFFFFFF0Zhao Yakui
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>
2007-09-25fix "mspec: handle shrinking virtual memory areas"Cliff Wickman
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>
2007-09-20Merge branch 'linux-2.6'Paul Mackerras
2007-09-19intel-agp: Fix i830 mask variable that changed with G33 supportDave Airlie
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>
2007-09-19pci: fix unterminated pci_device_id listsKees Cook
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>
2007-09-19mspec: handle shrinking virtual memory areasCliff Wickman
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>
2007-09-15sparc64 (and others): fix tty_ioctl.c buildTony Breeds
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>
2007-09-14Merge branch 'linux-2.6' into for-2.6.24Paul Mackerras
2007-09-11intel_agp: fix GTT map size on G33Zhenyu Wang
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>
2007-09-11intel_agp: fix stolen mem range on G33Zhenyu Wang
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>
2007-09-11tty: termios locking functions break with new termios typeDavid Miller
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>
2007-08-31Do not use the ia64 clocksource on non-ia64 architecturesLinus Torvalds
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>
2007-08-28Merge branch 'linux-2.6' into for-2.6.24Paul Mackerras
2007-08-27[MIPS] Delete duplicate inclusion of <linux/delay.h>.Ralf Baechle
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-08-25Merge branch 'agp-patches' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/airlied/agp-2.6 * 'agp-patches' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/agp-2.6: agp: balance ioremap checks agp: Add device id for P4M900 to via-agp module efficeon-agp leaks 'struct agp_bridge_data' in error paths of agp_efficeon_probe()
2007-08-25Merge branch 'drm-patches' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 * 'drm-patches' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: drm: ioremap return value checks drm/via: Fix dmablit when blit queue is full drm_rmmap_ioctl(): remove dead code
2007-08-25drm: ioremap return value checksScott Thompson
Signed-off-by: Scott Thompson <postfail <at> hushmail.com> Signed-off-by: Dave Airlie <airlied@linux.ie>
2007-08-25agp: balance ioremap checksScott Thompson
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>
2007-08-25agp: Add device id for P4M900 to via-agp moduleXavier Bachelot
Signed-off-by: Dave Airlie <airlied@linux.ie>