I broke that in my refactoring:
commit 7d2cd72a9a
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Fri May 29 16:05:42 2020 +0200
drm/shmem-helpers: Simplify dma-buf importing
I'm not entirely sure of the history here, but I suspect that in one
of the rebases or when applying the patch I moved the hunk from
drm_gem_shmem_prime_import_sg_table(), where it should be, to
drm_gem_shmem_create_with_handle(), which is totally wrong.
Remedy this.
Thanks for Thomas for the crucial hint in debugging this.
Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reported-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 7d2cd72a9a ("drm/shmem-helpers: Simplify dma-buf importing")
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200616114723.2363268-1-daniel.vetter@ffwll.ch
The helper drm_gem_shmem_create_object_cached() allocates an GEM SHMEM
object and sets the map_cached flag. Useful for drivers that want cached
mappings.
v3:
* style fixes
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200609090820.20256-2-tzimmermann@suse.de
- Ditch the ->pages array
- Make it a private gem bo, which means no shmem object, which means
fireworks if anyone calls drm_gem_object_get_pages. But we've just
made sure that's all covered.
v2: Rebase
v3: I forgot to remove the page_count mangling from the free path too.
Noticed by Boris while testing.
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Tested-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200529140542.2103713-1-daniel.vetter@ffwll.ch
Just a bit of light paranoia. Also sprinkle this check over
drm_gem_shmem_get_sg_table, which should only be called when
exporting, same for the pin/unpin functions, on which it relies to
work correctly.
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Boris Brezillon <boris.brezillon@collabora.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200511093554.211493-9-daniel.vetter@ffwll.ch
Currently this seems to work by converting the sgt into a pages array,
and then treating it like a native object. Do the right thing and
redirect mmap to the exporter.
With this nothing is calling get_pages anymore on imported dma-buf,
and we can start to remove the use of the ->pages array for that case.
v2: Rebase
Tested-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200511093554.211493-8-daniel.vetter@ffwll.ch
There's no direct harm, because for the shmem helpers these are noops
on imported buffers. The trouble is in the locks these take - I want
to change dma_buf_vmap locking, and so need to make sure that we only
ever take certain locks on one side of the dma-buf interface: Either
for exporters, or for importers.
v2: Change the control flow less compared to what's there (Thomas)
Tested-by: Boris Brezillon <boris.brezillon@collabora.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200514202256.490926-1-daniel.vetter@ffwll.ch
- Move the shmem helper section to the drm-mm.rst file, next to the
vram helpers. Makes a lot more sense there with the now wider scope.
Also, that's where the all the other backing storage stuff resides.
It's just the framebuffer helpers that should be in the kms helper
section.
- Try to clarify which functiosn are for implementing
drm_gem_object_funcs, and which for drivers to call directly. At
least one driver screwed that up a bit.
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200511093554.211493-4-daniel.vetter@ffwll.ch
Spelling out _unlocked for each and every driver is a annoying.
Especially if we consider how many drivers, do not know (or need to)
about the horror stories involving struct_mutex.
Just drop the suffix. It makes the API cleaner.
Done via the following script:
__from=drm_gem_object_put_unlocked
__to=drm_gem_object_put
for __file in $(git grep --name-only $__from); do
sed -i "s/$__from/$__to/g" $__file;
done
Pay special attention to the compat #define
v2: keep sed and #define removal separate
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org> (v1)
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515095118.2743122-14-emil.l.velikov@gmail.com
Was added by commit 95cf9264d5 ("x86, drm, fbdev: Do not specify
encrypted memory for video mappings"), then it was kept through various
changes.
While vram actually needs decrypted mappings this is not correct for
shmem gem objects which live in main memory not io memory, so remove the
call.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200228104723.18757-1-kraxel@redhat.com
Add map_cached bool to drm_gem_shmem_object, to request cached mappings
on a per-object base. Check the flag before adding writecombine to
pgprot bits.
Cc: stable@vger.kernel.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>
Tested-by: Guillaume Gardet <Guillaume.Gardet@arm.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200226154752.24328-2-kraxel@redhat.com
The fake offset is going to stay, so change the calling convention for
drm_gem_object_funcs.mmap to include the fake offset. Update all users
accordingly.
Note that this reverts 83b8a6f242 ("drm/gem: Fix mmap fake offset
handling for drm_gem_object_funcs.mmap") and on top then adds the fake
offset to drm_gem_prime_mmap to make sure all paths leading to
obj->funcs->mmap are consistent.
v3: move fake-offset tweak in drm_gem_prime_mmap() so we have this code
only once in the function (Rob Herring).
Fixes: 83b8a6f242 ("drm/gem: Fix mmap fake offset handling for drm_gem_object_funcs.mmap")
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20191127092523.5620-2-kraxel@redhat.com
Commit c40069cb7b ("drm: add mmap() to drm_gem_object_funcs")
introduced a GEM object mmap() hook which is expected to subtract the
fake offset from vm_pgoff. However, for mmap() on dmabufs, there is not
a fake offset.
To fix this, let's always call mmap() object callback with an offset of 0,
and leave it up to drm_gem_mmap_obj() to remove the fake offset.
TTM still needs the fake offset, so we have to add it back until that's
fixed.
Fixes: c40069cb7b ("drm: add mmap() to drm_gem_object_funcs")
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191024191859.31700-1-robh@kernel.org
Not obvious why this is needed. According to Deniel Vetter this is most
likely a historic artefact dating back to the days where drm drivers
exposed hardware registers as mmap'able gem objects, to avoid dumping
touching those registers. shmem gem objects surely don't need that ...
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20191016115203.20095-4-kraxel@redhat.com
Switch gem shmem helper to the new mmap() workflow,
from &gem_driver.fops.mmap to &drm_gem_object_funcs.mmap.
v2: Fix vm_flags and vm_page_prot handling.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20191016115203.20095-3-kraxel@redhat.com
Lockdep reports a circular locking dependency with pages_lock taken in
the shrinker callback. The deadlock can't actually happen with current
users at least as a BO will never be purgeable when pages_lock is held.
To be safe, let's use mutex_trylock() instead and bail if a BO is locked
already.
WARNING: possible circular locking dependency detected
5.3.0-rc1+ #100 Tainted: G L
------------------------------------------------------
kswapd0/171 is trying to acquire lock:
000000009b9823fd (&shmem->pages_lock){+.+.}, at: drm_gem_shmem_purge+0x20/0x40
but task is already holding lock:
00000000f82369b6 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x40
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (fs_reclaim){+.+.}:
fs_reclaim_acquire.part.18+0x34/0x40
fs_reclaim_acquire+0x20/0x28
__kmalloc_node+0x6c/0x4c0
kvmalloc_node+0x38/0xa8
drm_gem_get_pages+0x80/0x1d0
drm_gem_shmem_get_pages+0x58/0xa0
drm_gem_shmem_get_pages_sgt+0x48/0xd0
panfrost_mmu_map+0x38/0xf8 [panfrost]
panfrost_gem_open+0xc0/0xe8 [panfrost]
drm_gem_handle_create_tail+0xe8/0x198
drm_gem_handle_create+0x3c/0x50
panfrost_gem_create_with_handle+0x70/0xa0 [panfrost]
panfrost_ioctl_create_bo+0x48/0x80 [panfrost]
drm_ioctl_kernel+0xb8/0x110
drm_ioctl+0x244/0x3f0
do_vfs_ioctl+0xbc/0x910
ksys_ioctl+0x78/0xa8
__arm64_sys_ioctl+0x1c/0x28
el0_svc_common.constprop.0+0x90/0x168
el0_svc_handler+0x28/0x78
el0_svc+0x8/0xc
-> #0 (&shmem->pages_lock){+.+.}:
__lock_acquire+0xa2c/0x1d70
lock_acquire+0xdc/0x228
__mutex_lock+0x8c/0x800
mutex_lock_nested+0x1c/0x28
drm_gem_shmem_purge+0x20/0x40
panfrost_gem_shrinker_scan+0xc0/0x180 [panfrost]
do_shrink_slab+0x208/0x500
shrink_slab+0x10c/0x2c0
shrink_node+0x28c/0x4d8
balance_pgdat+0x2c8/0x570
kswapd+0x22c/0x638
kthread+0x128/0x130
ret_from_fork+0x10/0x18
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(fs_reclaim);
lock(&shmem->pages_lock);
lock(fs_reclaim);
lock(&shmem->pages_lock);
*** DEADLOCK ***
3 locks held by kswapd0/171:
#0: 00000000f82369b6 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x40
#1: 00000000ceb37808 (shrinker_rwsem){++++}, at: shrink_slab+0xbc/0x2c0
#2: 00000000f31efa81 (&pfdev->shrinker_lock){+.+.}, at: panfrost_gem_shrinker_scan+0x34/0x180 [panfrost]
Fixes: 17acb9f35e ("drm/shmem: Add madvise state and purge helpers")
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823021216.5862-6-robh@kernel.org
If a driver does its own management of pages, the shmem helper object's
pages array could be allocated when a SG table is not. There's not
really any good reason to tie putting pages with having a SG table when
freeing the object, so just put pages if the pages array is populated.
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190808222200.13176-3-robh@kernel.org
Add support to the shmem GEM helpers for tracking madvise state and
purging pages. This is based on the msm implementation.
The BO provides a list_head, but the list management is handled outside
of the shmem helpers as there are different locking requirements.
Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Eric Anholt <eric@anholt.net>
Acked-by: Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190805143358.21245-1-robh@kernel.org
Do not rely on including drm.h from drm_file.h,
as the include in drm_file.h will be dropped.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Sean Paul <sean@poorly.run>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Eric Anholt <eric@anholt.net>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190718161507.2047-8-sam@ravnborg.org
Right now, the BO is mapped as a cached region when ->vmap() is called
and the underlying object is not a dmabuf.
Doing that makes cache management a bit more complicated (you'd need
to call dma_map/unmap_sg() on the ->sgt field everytime the BO is about
to be passed to the GPU/CPU), so let's map the BO with writecombine
attributes instead (as done in most drivers).
Fixes: 2194a63a81 ("drm: Add library for shmem backed GEM objects")
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190529065121.13485-1-boris.brezillon@collabora.com
The shmem->pages[] array has "num_pages" elements so the > should be >=
to prevent reading beyond the end of the array. The shmem->pages[]
array is allocated in drm_gem_shmem_prime_import_sg_table().
Fixes: 2194a63a81 ("drm: Add library for shmem backed GEM objects")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190322064125.GA12551@kadam
This adds a library for shmem backed GEM objects.
v8:
- export drm_gem_shmem_create_with_handle
- call mapping_set_gfp_mask to set default zone to GFP_HIGHUSER
- Add helper drm_gem_shmem_get_pages_sgt()
v7:
- Use write-combine for mmap instead. This is the more common
case. (robher)
v6:
- Fix uninitialized variable issue in an error path (anholt).
- Add a drm_gem_shmem_vm_open() to the fops to get proper refcounting
of the pages (anholt).
v5:
- Drop drm_gem_shmem_prime_mmap() (Daniel Vetter)
- drm_gem_shmem_mmap(): Subtract drm_vma_node_start() to get the real
vma->vm_pgoff
- drm_gem_shmem_fault(): Use vmf->pgoff now that vma->vm_pgoff is correct
v4:
- Drop cache modes (Thomas Hellstrom)
- Add a GEM attached vtable
v3:
- Grammar (Sam Ravnborg)
- s/drm_gem_shmem_put_pages_unlocked/drm_gem_shmem_put_pages_locked/
(Sam Ravnborg)
- Add debug output in error path (Sam Ravnborg)
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190313004344.24169-1-robh@kernel.org
