In order to be fully threadsafe we need to check that the drm_gem_object
refcount is still 0 after acquiring the mutex in order to call the free
function. Otherwise, we may encounter scenarios like:
Thread A: Thread B:
drm_gem_close
unreference_unlocked
kref_put mutex_lock
... i915_gem_evict
... kref_get -> BUG
... i915_gem_unbind
... kref_put
... i915_gem_object_free
... mutex_unlock
mutex_lock
i915_gem_object_free -> BUG
i915_gem_object_unbind
kfree
mutex_unlock
Note that no driver is currently using the free_unlocked vfunc and it is
scheduled for removal, hasten that process.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=30454
Reported-and-Tested-by: Magnus Kessler <Magnus.Kessler@gmx.net>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
There were lots of places being inconsistent since handle count
looked like a kref but it really wasn't.
Fix this my just making handle count an atomic on the object,
and have it increase the normal object kref.
Now i915/radeon/nouveau drivers can drop the normal reference on
userspace object creation, and have the handle hold it.
This patch fixes a memory leak or corruption on unload, because
the driver had no way of knowing if a handle had been actually
added for this object, and the fbcon object needed to know this
to clean itself up properly.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Hook the GEM vm open/close ops into the generic drm vm open/close so
that the private vma entries are created and destroy appropriately.
Fixes the leak of the drm_vma_entries during the lifetime of the filp.
Reported-by: Matt Mackall <mpm@selenic.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
v2: Julien Cristau pointed out that @nondestructive results in
double-negatives and confusion when trying to interpret the parameter,
so use @force instead. Much easier to type as well. ;-)
And fix the miscompilation of vmgfx reported by Sedat Dilek.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
Destructive load-detection is very expensive and due to failings
elsewhere can trigger system wide stalls of up to 600ms. A simple
first step to correcting this is not to invoke such an expensive
and destructive load-detection operation automatically.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29536
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=16265
Reported-by: Bruno Prémont <bonbons@linux-vserver.org>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (33 commits)
drm/radeon/kms: fix typo in radeon_compute_pll_gain
drm/radeon/kms: try to detect tv vs monitor for underscan
drm/radeon/kms: fix sideport detection on newer rs880 boards
drm/radeon: fix passing wrong type to gem object create.
drm/radeon/kms: set encoder type to DVI for HDMI on evergreen
drm/radeon/kms: add back missing break in info ioctl
drm/radeon/kms: don't enable MSIs on AGP boards
drm/radeon/kms: fix agp mode setup on cards that use pcie bridges
drm: move dereference below check
drm: fix end of loop test
drm/radeon/kms: rework radeon_dp_detect() logic
drm/radeon/kms: add missing asic callback assignment for evergreen
drm/radeon/kms/DCE3+: switch pads to ddc mode when going i2c
drm/radeon/kms/pm: bail early if nothing's changing
drm/radeon/kms/atom: clean up dig atom handling
drm/radeon/kms: DCE3/4 transmitter fixes
drm/radeon/kms: rework encoder handling
drm/radeon/kms: DCE3/4 AdjustPixelPll updates
drm/radeon: Fix stack data leak
drm/radeon/kms: fix GTT/VRAM overlapping test
...
With the current screwed but its ABI, ioctls for the drm, Linus pointed out that we could allow userspace to specify the allocation size, but we pass it to the driver which then uses it blindly to store a struct. Now if userspace specifies the allocation size as smaller than the driver needs, the driver can possibly overwrite memory.
This patch restructures the driver ioctls so we store the structure size we are expecting, and make sure we allocate at least that size. The copy from/to userspace are still restricted to the size the user specifies, this allows ioctl structs to grow on both sides of the equation.
Up until now we didn't really use the DRM_IOCTL defines in the kernel, so this cleans them up and adds them for nouveau.
v2:
fix nouveau pushbuf arg (thanks to Ben for pointing it out)
Reported-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
unifdef-y and header-y has same semantic.
So there is no need to have both.
Drop the unifdef-y variant and sort all lines again
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
* 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (55 commits)
io-mapping: move asm include inside the config option
vgaarb: drop vga.h include
drm/radeon: Add probing of clocks from device-tree
drm/radeon: drop old and broken mesa warning
drm/radeon: Fix pci_map_page() error checking
drm: Remove count_lock for calling lastclose() after 58474713 (v2)
drm/radeon/kms: allow FG_ALPHA_VALUE on r5xx
drm/radeon/kms: another r6xx/r7xx CS checker fix
DRM: Replace kmalloc/memset combos with kzalloc
drm: expand gamma_set
drm/edid: Split mode lists out to their own header for readability
drm/edid: Rewrite mode parse to use the generic detailed block walk
drm/edid: Add detailed block walk for VTB extensions
drm/edid: Add detailed block walk for CEA extensions
drm: Remove unused fields from drm_display_info
drm: Use ENOENT consistently for the error return for an unmatched handle.
drm/radeon/kms: mark 3D power states as performance
drm: Only set DPMS once on the CRTC not after every encoder.
drm/radeon/kms: add additional quirk for Acer rv620 laptop
drm: Propagate error code from fb_create()
...
Fix up trivial conflicts in drivers/gpu/drm/drm_edid.c
Expand the crtc_gamma_set function to accept a starting offset. The
reason for this is to eventually use this function for setcolreg from
drm_fb_helper.c. The fbdev colormap function can start at any offset in
the color map.
Signed-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
(For some reason I thought that went in ages ago ...)
This fixes support for PCI domains in what should hopefully be a backward
compatible way along with a change to libdrm.
When the interface version is set to 1.4, we assume userspace understands
domains and the world is at peace. We thus pass proper domain numbers
instead of 0 to userspace.
The newer libdrm will then try 1.4 first, and fallback to 1.1, along with
ignoring domains in the later case (well, except on alpha of course)
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (55 commits)
workqueue: mark init_workqueues() as early_initcall()
workqueue: explain for_each_*cwq_cpu() iterators
fscache: fix build on !CONFIG_SYSCTL
slow-work: kill it
gfs2: use workqueue instead of slow-work
drm: use workqueue instead of slow-work
cifs: use workqueue instead of slow-work
fscache: drop references to slow-work
fscache: convert operation to use workqueue instead of slow-work
fscache: convert object to use workqueue instead of slow-work
workqueue: fix how cpu number is stored in work->data
workqueue: fix mayday_mask handling on UP
workqueue: fix build problem on !CONFIG_SMP
workqueue: fix locking in retry path of maybe_create_worker()
async: use workqueue for worker pool
workqueue: remove WQ_SINGLE_CPU and use WQ_UNBOUND instead
workqueue: implement unbound workqueue
workqueue: prepare for WQ_UNBOUND implementation
libata: take advantage of cmwq and remove concurrency limitations
workqueue: fix worker management invocation without pending works
...
Fixed up conflicts in fs/cifs/* as per Tejun. Other trivial conflicts in
include/linux/workqueue.h, kernel/trace/Kconfig and kernel/workqueue.c
* 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (204 commits)
agp: intel-agp: do not use PCI resources before pci_enable_device()
agp: efficeon-agp: do not use PCI resources before pci_enable_device()
drm: kill BKL from common code
drm/kms: Simplify setup of the initial I2C encoder config.
drm,io-mapping: Specify slot to use for atomic mappings
drm/radeon/kms: only expose underscan on avivo chips
drm/radeon: add new pci ids
drm: Cleanup after failing to create master->unique and dev->name
drm/radeon: tone down overchatty acpi debug messages.
drm/radeon/kms: enable underscan option for digital connectors
drm/radeon/kms: fix calculation of h/v scaling factors
drm/radeon/kms/igp: sideport is AMD only
drm/radeon/kms: handle the case of no active displays properly in the bandwidth code
drm: move ttm global code to core drm
drm/i915: Clear the Ironlake dithering flags when the pipe doesn't want it.
drm/radeon/kms: make sure HPD is set to NONE on analog-only connectors
drm/radeon/kms: make sure rio_mem is valid before unmapping it
drm/agp/i915: trim stolen space to 32M
drm/i915: Unset cursor if out-of-bounds upon mode change (v4)
drm/i915: Unreference object not handle on creation
...
* 'kms-merge' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
kgdb,docs: Update the kgdb docs to include kms
drm_fb_helper: Preserve capability to use atomic kms
i915: when kgdb is active display compression should be off
drm/i915: use new fb debug hooks
drm: add KGDB/KDB support
fb: add hooks to handle KDB enter/exit
kgdboc: Add call backs to allow kernel mode switching
vt,console,kdb: automatically set kdb LINES variable
vt,console,kdb: implement atomic console enter/leave functions
Implement the callbacks for KDB entry/exit via the drm helpers.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
This restricts the use of the big kernel lock to the i830 and i810
device drivers. The three remaining users in common code (open, ioctl
and release) get converted to a new mutex, the drm_global_mutex,
making the locking stricter than the big kernel lock.
This may have a performance impact, but only in those cases that
currently don't use DRM_UNLOCKED flag in the ioctl list and would
benefit from that anyway.
The reason why i810 and i830 cannot use drm_global_mutex in their
mmap functions is a lock-order inversion problem between the current
use of the BKL and mmap_sem in these drivers. Since the BKL has
release-on-sleep semantics, it's harmless but it would cause trouble
if we replace the BKL with a mutex.
Instead, these drivers get their own ioctl wrappers that take the
BKL around every ioctl call and then set their own handlers as
DRM_UNLOCKED.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: David Airlie <airlied@linux.ie>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
I wrote this for the prime sharing work, but I also noticed other external
non-upstream drivers from a large company carrying a similiar patch, so I
may as well ship it in master.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Intel Core i3/5 platforms with integrated graphics support both CPU and
GPU turbo mode. CPU turbo mode is opportunistic: the CPU will use any
available power to increase core frequencies if thermal headroom is
available. The GPU side is more manual however; the graphics driver
must monitor GPU power and temperature and coordinate with a core
thermal driver to take advantage of available thermal and power headroom
in the package.
The intelligent power sharing (IPS) driver is intended to coordinate
this activity by monitoring MCP (multi-chip package) temperature and
power, allowing the CPU and/or GPU to increase their power consumption,
and thus performance, when possible. The goal is to maximize
performance within a given platform's TDP (thermal design point).
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
This interface allows userspace to request hyperz support, it probably
needs more locking, and really reporting that you can have hyperz is racy
since someone else might get it before you do.
v2: modify so we pass 0 valued packets to let DDX/r300c keep working.
also fixed incorrect 0x4f1c reference.
v3: fixup zb_bw_cntl so older drivers keep working
v4: add locking, fixup SC_HYPERZ_EN - patch stream to disable hiz
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'drm-radeon-next' of ../drm-radeon-next: (333 commits)
drm/radeon/kms: trivial code style fixes for audio
drm/radeon: remove viewport transform from r6xx/r7xx blit emit
drm/radeon: group r6xx/r7xx newly sequential blit state
drm/radeon: reorder r6xx/r7xx blit state emit to make more regs sequential
drm/radeon: r6xx/r7xx move vport clipping to a single packet
drm/radeon: group r6xx/r7xx sequential blit state
drm/radeon: remove duplicate state emit in r6xx/r7xx blit
drm/radeon: add comments to r6xx/r7xx blit state
drm/radeon/kms/r7xx: add workaround for hw issue with HDP flush
drm/radeon/kms: remove rs4xx gart limit
drm: radeon: fix sign bug
drm/radeon/kms: check/restore sanity before doing anything else with GPU.
drm/radeon: fall back to GTT if bo creation/validation in VRAM fails.
drm/radeon/kms: add ioport register access
drm/radeon/kms: enable HDMI audio on RS600/RS690/RS740
drm/radeon/kms: track audio engine state, do not use not setup timer
drm/radeon/kms/r6xx+: add query for tile config (v2)
drm/radeon/kms: fix CS alignment checking for tiling (v2)
drm/radeon/kms: add tiling support to the cs checker for r6xx/r7xx
drm/radeon/kms: Add crtc tiling setup support for evergreen
...
sil164 transmitters are used for DVI outputs on Intel/nvidia and ATI setups.
So far only nouveau can use this driver.
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Tested-by: Patrice Mandin <patmandin@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Userspace needs this information to access tiled
buffers via the CPU.
v2: rebased on evergreen accel changes
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Workqueue can now handle high concurrency. Convert drm_crtc_helper to
use system_nrt_wq instead of slow-work. The conversion is mostly
straight forward. One difference is that drm_helper_hpd_irq_event()
no longer blocks and can be called from any context.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David Airlie <airlied@linux.ie>
Cc: dri-devel@lists.freedesktop.org
There's no convenient/reliable way for drivers to both obey the dithering
mode property, and to be able to attempt to provide a good default in all
cases.
This commit adds an "auto" method to the property which drivers can default
to if they wish, whilst still allowing the user to override the choice as
they do now.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
More explicit than dpms. Same as the encoder disable function.
Need this to explicity disconnect plls from crtcs for reuse when you
plls:crtcs ratio isn't 1:1.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
* drm-intel-lru:
drm: implement helper functions for scanning lru list
drm_mm: extract check_free_mm_node
drm: sane naming for drm_mm.c
drm: kill dead code in drm_mm.c
drm: kill drm_mm_node->private
drm: use list_for_each_entry in drm_mm.c
* drm-platform:
drm: Make sure the DRM offset matches the CPU
drm: Add __arm defines to DRM
drm: Add support for platform devices to register as DRM devices
drm: Remove drm_resource wrappers
These helper functions can be used to efficiently scan lru list
for eviction. Eviction becomes a three stage process:
1. Scanning through the lru list until a suitable hole has been found.
2. Scan backwards to restore drm_mm consistency and find out which
objects fall into the hole.
3. Evict the objects that fall into the hole.
These helper functions don't allocate any memory (at the price of
not allowing any other concurrent operations). Hence this can also be
used for ttm (which does lru scanning under a spinlock).
Evicting objects in this fashion should be more fair than the current
approach by i915 (scan the lru for a object large enough to contain
the new object). It's also more efficient than the current approach used
by ttm (uncoditionally evict objects from the lru until there's enough
free space).
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Thomas Hellstrom <thellstrom@vmwgfx.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Yeah, I've kinda noticed that fl_entry is the free stack. Still
give it (and the memory node list ml_entry) decent names.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Thomas Hellstrom <thellstrom@vmwgfx.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Only ever assigned, never used.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[glisse: I will re-add if needed for range-restricted allocations]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Repeated ttm_page_alloc_init/fini fails noisily because the pool
manager kobj isn't zeroed out between uses (we could do just that but
statically allocated kobjects are generally considered a bad thing).
Move it to kzalloc'ed memory.
Note that this patch drops the refcounting behavior of the pool
allocator init/fini functions: it would have led to a race condition
in its current form, and anyway it was never exploited.
This fixes a regression with reloading kms modules at runtime, since
page allocator was introduced.
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Allows us to track each process that requests and completes events.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This is needed to enable accel in the ddx. However,
due to a bug in older versions of the ddx, it relies
on accel being disabled in order to load properly on
evergreen chips. To maintain compatility, we add a new
get accel param and call that from the ddx. The old one
always returns false for evergreen cards.
[this fixes a regression with older userspaces on newer kernels].
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'drm-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (41 commits)
drm/radeon/kms: make sure display hw is disabled when suspending
drm/vmwgfx: Allow userspace to change default layout. Bump minor.
drm/vmwgfx: Fix framebuffer modesetting
drm/vmwgfx: Fix vga save / restore with display topology.
vgaarb: use MIT license
vgaarb: convert pr_devel() to pr_debug()
drm: fix typos in Linux DRM Developer's Guide
drm/radeon/kms/pm: voltage fixes
drm/radeon/kms/pm: radeon_set_power_state fixes
drm/radeon/kms/pm: patch default power state with default clocks/voltages on r6xx+
drm/radeon/kms/pm: enable SetVoltage on r7xx/evergreen
drm/radeon/kms/pm: add support for SetVoltage cmd table (V2)
drm/radeon/kms/evergreen: add initial CS parser
drm/kms: disable/enable poll around switcheroo on/off
drm/nouveau: fixup confusion over which handle the DSM is hanging off.
drm/nouveau: attempt to get bios from ACPI v3
drm/nv50: cast IGP memory location to u64 before shifting
drm/ttm: Fix ttm_page_alloc.c
drm/ttm: Fix cached TTM page allocation.
drm/vmwgfx: Remove some leftover debug messages.
...
The host may change the layout and, since the change is
communicated to the master, the master needs a way to
communicate the change to the kernel driver.
The minor version number is bumped to advertize the
availability of this feature.
Signed-off-by: Jakob Bornecrantz <jakob@vmware.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This will let userland only try to use the new media decode
functionality when the appropriate kernel is present.
Signed-off-by: Zou Nan hai <nanhai.zou@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
* 'nouveau/for-airlied' of ../drm-nouveau-next:
drm/nv50: cast IGP memory location to u64 before shifting
drm/nv50: use alternate source of SOR_MODE_CTRL for DP hack
drm/nouveau: fix dual-link displays when plugged into single-link outputs
drm/nv50: obey dcb->duallink_possible
drm/nv50: fix duallink_possible calculation for DCB 4.0 cards
drm/nouveau: don't execute INIT_GPIO unless we're really running the table
drm/nv40: allow cold-booting of nv4x chipsets
drm/nouveau: fix POST detection for certain chipsets
drm/nouveau: Add getparam for current PTIMER time.
drm/nouveau: allow cursor image and position to survive suspend
Allow platform devices without PCI resources to be DRM devices.
[airlied: fixup warnings with dev pointers]
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Remove the drm_resource wrappers and directly use the
actual PCI and/or platform functions in their place.
[airlied: fixup nouveau properly to build]
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This will be useful for computing GPU-CPU latency, including
GL_ARB_timer_query extension.
Signed-off-by: Marcin Kościelnicki <koriakin@0x04.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Introduces a more complete intel_ring_buffer structure with callbacks
for setup and management of a particular ringbuffer, and converts the
render ring buffer consumers to use it.
Signed-off-by: Zou Nan hai <nanhai.zou@intel.com>
Signed-off-by: Xiang Hai hao <haihao.xiang@intel.com>
[anholt: Fixed up whitespace fail and rebased against prep patches]
Signed-off-by: Eric Anholt <eric@anholt.net>
* 'drm-for-2.6.35' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (207 commits)
drm/radeon/kms/pm/r600: select the mid clock mode for single head low profile
drm/radeon: fix power supply kconfig interaction.
drm/radeon/kms: record object that have been list reserved
drm/radeon: AGP memory is only I/O if the aperture can be mapped by the CPU.
drm/radeon/kms: don't default display priority to high on rs4xx
drm/edid: fix typo in 1600x1200@75 mode
drm/nouveau: fix i2c-related init table handlers
drm/nouveau: support init table i2c device identifier 0x81
drm/nouveau: ensure we've parsed i2c table entry for INIT_*I2C* handlers
drm/nouveau: display error message for any failed init table opcode
drm/nouveau: fix init table handlers to return proper error codes
drm/nv50: support fractional feedback divider on newer chips
drm/nv50: fix monitor detection on certain chipsets
drm/nv50: store full dcb i2c entry from vbios
drm/nv50: fix suspend/resume with DP outputs
drm/nv50: output calculated crtc pll when debugging on
drm/nouveau: dump pll limits entries when debugging is on
drm/nouveau: bios parser fixes for eDP boards
drm/nouveau: fix a nouveau_bo dereference after it's been destroyed
drm/nv40: remove some completed ctxprog TODOs
...
We want to be able to prevent the delayed workqueue from changing state
while we're reclocking, so add an API to block and unblock it.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
