An unlikely race could case a bo to be returned reserved on an error path.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: NJerome Glisse <jglisse@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This reverts commit dfadbbdb.

Further upstream discussion between Marek and Thomas decided this wasn't
fully baked and needed further work, so revert it before it hits mainline.
Signed-off-by: NDave Airlie <airlied@redhat.com>

Used by the vmwgfx driver.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Fixes an information leak to userspace, we were handing out un-zeroed pages
for any newly created TTM_PL_TT buffer.
Reported-by: NMarcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>
Tested-by: NMarcin Slusarz <marcin.slusarz@gmail.com>
Cc: stable@kernel.org
Signed-off-by: NDave Airlie <airlied@redhat.com>

Sometimes we want to know whether a buffer is busy and wait for it (bo_wait).
However, sometimes it would be more useful to be able to query whether
a buffer is busy and being either read or written, and wait until it's stopped
being either read or written. The point of this is to be able to avoid
unnecessary waiting, e.g. if a GPU has written something to a buffer and is now
reading that buffer, and a CPU wants to map that buffer for read, it needs to
only wait for the last write. If there were no write, there wouldn't be any
waiting needed.

This, or course, requires user space drivers to send read/write flags
with each relocation (like we have read/write domains in radeon, so we can
actually use those for something useful now).

Now how this patch works:

The read/write flags should passed to ttm_validate_buffer. TTM maintains
separate sync objects of the last read and write for each buffer, in addition
to the sync object of the last use of a buffer. ttm_bo_wait then operates
with one the sync objects.
Signed-off-by: NMarek Olšák <maraeo@gmail.com>
Reviewed-by: NJerome Glisse <jglisse@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This was true for new TTM_PL_SYSTEM and new TTM_PL_TT cases, but wasn't
the case on TTM_PL_SYSTEM<->TTM_PL_TT moves, which causes trouble on some
paths as nouveau's move_notify() hook requires that the dma addresses be
valid at this point.
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

ttm_tt_destroy kfrees passed object, so we need to nullify
a reference to it.
Signed-off-by: NMarcin Slusarz <marcin.slusarz@gmail.com>
Cc: stable@kernel.org
Reviewed-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: NArun Sharma <asharma@fb.com>
Reviewed-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NJan Engelhardt <jengelh@medozas.de>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Nouveau doesn't have enough information at ttm_backend_func.bind() time
to implement things like tiled GART, or to keep a buffer at a constant
address in the GPU virtual address space no matter where in physical
memory it's placed.

To resolve this, nouveau will handle binding of all buffers to the GPU
itself from the move_notify() hook.  This commit ensures it's called
for all buffer moves.

Talked to Dave about the impact on radeon, which uses move_notify, it
doesn't look like anything should break there.
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>
Reviewed-by: NThomas Hellstrom <thomas@shipmail.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Make ttm_bo::ttm_bo_device_release call cancel_delayed_work_sync()
instead of calling cancel_delayed_work() followed by
flush_scheduled_work().

This is to prepare for the deprecation and removal of
flush_scheduled_work().
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc:: Thomas Hellstrom <thellstrom@vmware.com>
Cc:: Dave Airlie <airlied@redhat.com>

This patch attempts to fix up shortcomings with the current calling
sequences.

1) There's a fastpath where no locking occurs and only io_mem_reserved is
   called to obtain needed info for mapping. The fastpath is set per
   memory type manager.
2) If the fastpath is disabled, io_mem_reserve and io_mem_free will be exactly
   balanced and not called recursively for the same struct ttm_mem_reg.
3) Optionally the driver can choose to enable a per memory type manager LRU
   eviction mechanism that, when io_mem_reserve returns -EAGAIN will attempt
   to kill user-space mappings of memory in that manager to free up needed
   resources
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: NBen Skeggs <bskeggs@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Rather than having the driver supply the validation sequence, leave that
responsibility to TTM. This saves some confusion and a function argument.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Drastically reduce the number of spin lock / unlock operations by performing
unreserving and fencing under global locks.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: NJerome Glisse <j.glisse@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The bo lock used only to protect the bo sync object members, and since it
is a per bo lock, fencing a buffer list will see a lot of locks and unlocks.
Replace it with a per-device lock that protects the sync object members on
*all* bos. Reading and setting these members will always be very quick, so
the risc of heavy lock contention is microscopic. Note that waiting for
sync objects will always take place outside of this lock.

The bo device fence lock will eventually be replaced with a seqlock /
rcu mechanism so we can determine that a bo is idle under a
rcu / read seqlock.

However this change will allow us to batch fencing and unreserving of
buffers with a minimal amount of locking.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: NJerome Glisse <j.glisse@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Add an aid for the driver to detect deadlocks on multi-bo reservations
Update documentation.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: NJerome Glisse <j.glisse@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Makes it possible to reserve a list of buffer objects with a single
spin lock / unlock if there is no contention.
Should improve cpu usage on SMP kernels.

v2: Initialize private list members on reserve and don't call
ttm_bo_list_ref_sub() with zero put_count.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

A process suspended waiting for a higher sequence or no sequence to unreserve,
a bo may be beaten to the reservation by a process with a lower sequence.
In that case the first process should give up trying to reserve and
return -EAGAIN. In order for that to happen, we must wake waiting processes
when we change sequence, so that they have a chance to detect the new
sequence.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Call destroy() on _all_ ttm_bo_init() failures, and make sure that
behavior is documented in the function description.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This breaks vmwgfx non-root EGL clients and is a remnant from the
TTM user-space interface. This test should be done in the driver.
Replace the remaining placement test with a BUG_ON, since triggering
it is a driver bug.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The sync object may disappear as soon as we release the bo::lock, so
take a reference on it while we use it.
One option would be to call sync_object_flush() before releasing the bo::lock,
but that would put an atomic requirement on that function.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Since we're doing this outside of a spinlock to provide the necessary
barriers, add an explicit barrier.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Replace with BUG_ON(). These error messages remained from the time
when TTM was initialized from user-space. Nowadays hitting one of those
is really a kernel bug.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Remove an obsolete comment about mm nodes.
Document the new bo range manager interface.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This commit replaces the ttm_bo_cleanup_ref function with two new functions.
One for the case where the bo is not yet on the delayed destroy list, and
one for the case where the bo was on the delayed destroy list, at least at
the time of call. This makes it possible to optimize the two cases somewhat.

It also enables the possibility to directly destroy buffers on the
delayed delete list when they are about to be evicted or swapped out.
Currently they were only evicted / swapped and destruction was left for the
delayed buffer destruction thread.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Release the lru spinlock early.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Function ttm_bo_wait_unreserved can be slightly simplified.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

We need the unlocked variant for the new codepath introduced to fix the
race condition in master recently.
Signed-off-by: NDave Airlie <airlied@redhat.com>

This fixes a race pointed out by Dave Airlie where we don't take a buffer
object about to be destroyed off the LRU lists properly. It also fixes a rare
case where a buffer object could be destroyed in the middle of an
accelerated eviction.

The patch also adds a utility function that can be used to prematurely
release GPU memory space usage of an object waiting to be destroyed.
For example during eviction or swapout.

The above mentioned commit didn't queue the buffer on the delayed destroy
list under some rare circumstances. It also didn't completely honor the
remove_all parameter.

Fixes:
https://bugzilla.redhat.com/show_bug.cgi?id=615505
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=591061Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Nouveau will need this on GeForce 8 and up to account for the GPU
reordering physical VRAM for some memory types.
Reviewed-by: NJerome Glisse <jglisse@redhat.com>
Acked-by: NThomas Hellström <thellstrom@vmware.com>
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>

Existing core code/drivers call drm_mm_put_block on ttm_mem_reg.mm_node
directly.  Future patches will modify TTM behaviour in such a way that
ttm_mem_reg.mm_node doesn't necessarily belong to drm_mm.
Reviewed-by: NJerome Glisse <jglisse@redhat.com>
Acked-by: NThomas Hellström <thellstrom@vmware.com>
Signed-off-by: NBen Skeggs <bskeggs@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: NDave Airlie <airlied@redhat.com>

Only ever assigned, never used.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
[glisse: I will re-add if needed for range-restricted allocations]
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDave Airlie <airlied@redhat.com>

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: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

It's unused and buggy in its current form, since it can place a bo
in the reserved state without removing it from lru lists.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

All TTM driver have been converted to new io_mem_reserve/free
interface which allow driver to choose and return proper io
base, offset to core TTM for ioremapping if necessary. This
patch remove what is now deadcode.

V2 adapt to match with change in first patch of the patchset
V3 update after io_mem_reserve/io_mem_free callback balancing
V4 adjust to minor cleanup
V5 remove the needs ioremap flag
V6 keep the ioremapping facility in TTM

[airlied- squashed driver removals in here also]
Signed-off-by: NJerome Glisse <jglisse@redhat.com>
Reviewed-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

On fault the driver is given the opportunity to perform any operation
it sees fit in order to place the buffer into a CPU visible area of
memory. This patch doesn't break TTM users, nouveau, vmwgfx and radeon
should keep working properly. Future patch will take advantage of this
infrastructure and remove the old path from TTM once driver are
converted.

V2 return VM_FAULT_NOPAGE if callback return -EBUSY or -ERESTARTSYS
V3 balance io_mem_reserve and io_mem_free call, fault_reserve_notify
   is responsible to perform any necessary task for mapping to succeed
V4 minor cleanup, atomic_t -> bool as member is protected by reserve
   mecanism from concurent access
V5 the callback is now responsible for iomapping the bo and providing
   a virtual address this simplify TTM and will allow to get rid of
   TTM_MEMTYPE_FLAG_NEEDS_IOREMAP
V6 use the bus addr data to decide to ioremap or this isn't needed
   but we don't necesarily need to ioremap in the callback but still
   allow driver to use static mapping
Signed-off-by: NJerome Glisse <jglisse@redhat.com>
Reviewed-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

There is case where we want to be able to wait only for the
GPU while not waiting for other buffer to be unreserved. This
patch split the no_wait argument all the way down in the whole
ttm path so that upper level can decide on what to wait on or
not.

[airlied: squashed these 4 for bisectability reasons.]
drm/radeon/kms: update to TTM no_wait splitted argument
drm/nouveau: update to TTM no_wait splitted argument
drm/vmwgfx: update to TTM no_wait splitted argument
[vmwgfx patch: Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>]
Signed-off-by: NJerome Glisse <jglisse@redhat.com>
Acked-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>