Commit graph

13 commits

Author SHA1 Message Date
Gerd Hoffmann
e551655399 drm: call drm_gem_object_funcs.mmap with fake offset
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
2019-12-06 11:18:11 +01:00
Rob Herring
83b8a6f242 drm/gem: Fix mmap fake offset handling for drm_gem_object_funcs.mmap
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
2019-10-29 13:29:21 -05:00
Gerd Hoffmann
1bf01e1e35 drm/shmem: drop VM_IO
VM_IO is wrong here, shmem uses normal ram not io memory.

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/20191016115203.20095-5-kraxel@redhat.com
2019-10-17 13:59:16 +02:00
Gerd Hoffmann
5da932604d drm/shmem: drop VM_DONTDUMP
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
2019-10-17 13:59:16 +02:00
Gerd Hoffmann
0be8958936 drm/shmem: switch shmem helper to &drm_gem_object_funcs.mmap
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
2019-10-17 13:59:16 +02:00
Rob Herring
dfbc7a46b9 drm/shmem: Use mutex_trylock in drm_gem_shmem_purge
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
2019-08-23 11:54:45 -05:00
Rob Herring
4fa3d66f13 drm/shmem: Do dma_unmap_sg before purging pages
Calling dma_unmap_sg() in drm_gem_shmem_free_object() is too late if the
backing pages have already been released by the shrinker. The result is
the following abort:

Unable to handle kernel paging request at virtual address ffff8000098ed000
Mem abort info:
  ESR = 0x96000147
  Exception class = DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
Data abort info:
  ISV = 0, ISS = 0x00000147
  CM = 1, WnR = 1
swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000002f51000
[ffff8000098ed000] pgd=00000000401f8003, pud=00000000401f7003, pmd=00000000401b1003, pte=00e80000098ed712
Internal error: Oops: 96000147 [#1] SMP
Modules linked in: panfrost gpu_sched
CPU: 5 PID: 902 Comm: gnome-shell Not tainted 5.3.0-rc1+ #95
Hardware name: 96boards Rock960 (DT)
pstate: 40000005 (nZcv daif -PAN -UAO)
pc : __dma_inv_area+0x40/0x58
lr : arch_sync_dma_for_cpu+0x28/0x30
sp : ffff00001321ba30
x29: ffff00001321ba30 x28: ffff00001321bd08
x27: 0000000000000000 x26: 0000000000000009
x25: 0000ffffc1f86170 x24: 0000000000000000
x23: 0000000000000000 x22: 0000000000000000
x21: 0000000000021000 x20: ffff80003bb2d810
x19: 00000000098ed000 x18: 0000000000000000
x17: 0000000000000000 x16: ffff800023fd9480
x15: 0000000000000000 x14: 0000000000000000
x13: 0000000000000000 x12: 0000000000000000
x11: 00000000fffb9fff x10: 0000000000000000
x9 : 0000000000000000 x8 : ffff800023fd9c18
x7 : 0000000000000000 x6 : 00000000ffffffff
x5 : 0000000000000000 x4 : 0000000000021000
Purging 5693440 bytes
x3 : 000000000000003f x2 : 0000000000000040
x1 : ffff80000990e000 x0 : ffff8000098ed000
Call trace:
 __dma_inv_area+0x40/0x58
 dma_direct_sync_single_for_cpu+0x7c/0x80
 dma_direct_unmap_page+0x80/0x88
 dma_direct_unmap_sg+0x54/0x80
 drm_gem_shmem_free_object+0xfc/0x108
 panfrost_gem_free_object+0x118/0x128 [panfrost]
 drm_gem_object_free+0x18/0x90
 drm_gem_object_put_unlocked+0x58/0x80
 drm_gem_object_handle_put_unlocked+0x64/0xb0
 drm_gem_object_release_handle+0x70/0x98
 drm_gem_handle_delete+0x64/0xb0
 drm_gem_close_ioctl+0x28/0x38
 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+0x88/0x150
 el0_svc_handler+0x28/0x78
 el0_svc+0x8/0xc
 Code: 8a230000 54000060 d50b7e20 14000002 (d5087620)

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>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823021216.5862-5-robh@kernel.org
2019-08-23 11:54:40 -05:00
Rob Herring
3bf5189d93 drm/shmem: Put pages independent of a SG table being set
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
2019-08-12 14:18:42 -06:00
Rob Herring
17acb9f35e drm/shmem: Add madvise state and purge helpers
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
2019-08-08 15:54:10 -06:00
Sam Ravnborg
d3ea256aa4 drm: direct include of drm.h in drm_gem_shmem_helper.c
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
2019-07-19 23:24:17 +02:00
Boris Brezillon
be7d9f05c5 drm/gem_shmem: Use a writecombine mapping for ->vaddr
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
2019-06-10 09:14:01 -06:00
Dan Carpenter
3a3fe6e766 drm: shmem: Off by one in drm_gem_shmem_fault()
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
2019-04-01 10:44:34 -07:00
Noralf Trønnes
2194a63a81 drm: Add library for shmem backed GEM objects
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
2019-03-14 12:06:44 -07:00