Add the new vma_set_file() function to allow changing
vma->vm_file with the necessary refcount dance.
v2: add more users of this.
v3: add missing EXPORT_SYMBOL, rebase on mmap cleanup,
add comments why we drop the reference on two occasions.
v4: make it clear that changing an anonymous vma is illegal.
v5: move vma_set_file to mm/util.c
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v2)
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://patchwork.freedesktop.org/patch/399360/
Patch "495c10cc1c0c CHROMIUM: dma-buf: restore args..."
adds a workaround for a bug in mmap_region.
As the comment states ->mmap() callback can change
vma->vm_file and so we might call fput() on the wrong file.
Revert the workaround and proper fix this in mmap_region.
v2: drop the extra if in dma_buf_mmap as well
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://patchwork.freedesktop.org/patch/399359/
The kernel test robot is not happy with that.
This reverts commit 0227da01f2.
Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/394772/
The kernel test robot is not happy with that.
This reverts commit 2b5b95b1ff.
Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/394773/
Here is the warning message:
drivers/dma-buf/dma-buf.c:917 dma_buf_map_attachment()
error: 'sg_table' dereferencing possible ERR_PTR()
Fix by adding error checking before dereferencing the pointer.
Fixes: ac80cd17a6 ("dma-buf: Clarify that dma-buf sg lists are page aligned")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jianxin Xiong <jianxin.xiong@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/398485/
Add the new vma_set_file() function to allow changing
vma->vm_file with the necessary refcount dance.
v2: add more users of this.
v3: add missing EXPORT_SYMBOL, rebase on mmap cleanup,
add comments why we drop the reference on two occasions.
v4: make it clear that changing an anonymous vma is illegal.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v2)
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/394773/
Patch "495c10cc1c0c CHROMIUM: dma-buf: restore args..."
adds a workaround for a bug in mmap_region.
As the comment states ->mmap() callback can change
vma->vm_file and so we might call fput() on the wrong file.
Revert the workaround and proper fix this in mmap_region.
v2: drop the extra if in dma_buf_mmap as well
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/394772/
The dma-buf API have been used under the assumption that the sg lists
returned from dma_buf_map_attachment() are fully page aligned. Lots of
stuff can break otherwise all over the place. Clarify this in the
documentation and add a check when DMA API debug is enabled.
Signed-off-by: Jianxin Xiong <jianxin.xiong@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1602692161-107096-1-git-send-email-jianxin.xiong@intel.com
This patch updates dma_buf_vunmap() and dma-buf's vunmap callback to
use struct dma_buf_map. The interfaces used to receive a buffer address.
This address is now given in an instance of the structure.
Users of the functions are updated accordingly. This is only an interface
change. It is currently expected that dma-buf memory can be accessed with
system memory load/store operations.
v2:
* include dma-buf-heaps and i915 selftests (kernel test robot)
* initialize cma_obj before using it in drm_gem_cma_free_object()
(kernel test robot)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Tomasz Figa <tfiga@chromium.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200925115601.23955-4-tzimmermann@suse.de
This patch updates dma_buf_vmap() and dma-buf's vmap callback to use
struct dma_buf_map.
The interfaces used to return a buffer address. This address now gets
stored in an instance of the structure that is given as an additional
argument. The functions return an errno code on errors.
Users of the functions are updated accordingly. This is only an interface
change. It is currently expected that dma-buf memory can be accessed with
system memory load/store operations.
v3:
* update fastrpc driver (kernel test robot)
v2:
* always clear map parameter in dma_buf_vmap() (Daniel)
* include dma-buf-heaps and i915 selftests (kernel test robot)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Tomasz Figa <tfiga@chromium.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200925115601.23955-3-tzimmermann@suse.de
The new type struct dma_buf_map represents a mapping of dma-buf memory
into kernel space. It contains a flag, is_iomem, that signals users to
access the mapped memory with I/O operations instead of regular loads
and stores.
It was assumed that DMA buffer memory can be accessed with regular load
and store operations. Some architectures, such as sparc64, require the
use of I/O operations to access dma-map buffers that are located in I/O
memory. Providing struct dma_buf_map allows drivers to implement this.
This was specifically a problem when refreshing the graphics framebuffer
on such systems. [1]
As the first step, struct dma_buf stores an instance of struct dma_buf_map
internally. Afterwards, dma-buf's vmap and vunmap interfaces are be
converted. Finally, affected drivers can be fixed.
v3:
* moved documentation into separate patch
* test for NULL pointers with !<ptr>
[1] https://lore.kernel.org/dri-devel/20200725191012.GA434957@ravnborg.org/
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200925115601.23955-2-tzimmermann@suse.de
NULL pointer dereference is observed while exporting the dmabuf but
failed to allocate the 'struct file' which results into the dropping of
the allocated dentry corresponding to this file in the dmabuf fs, which
is ending up in dma_buf_release() and accessing the uninitialzed
dentry->d_fsdata.
Call stack on 5.4 is below:
dma_buf_release+0x2c/0x254 drivers/dma-buf/dma-buf.c:88
__dentry_kill+0x294/0x31c fs/dcache.c:584
dentry_kill fs/dcache.c:673 [inline]
dput+0x250/0x380 fs/dcache.c:859
path_put+0x24/0x40 fs/namei.c:485
alloc_file_pseudo+0x1a4/0x200 fs/file_table.c:235
dma_buf_getfile drivers/dma-buf/dma-buf.c:473 [inline]
dma_buf_export+0x25c/0x3ec drivers/dma-buf/dma-buf.c:585
Fix this by checking for the valid pointer in the dentry->d_fsdata.
Fixes: 4ab59c3c63 ("dma-buf: Move dma_buf_release() from fops to dentry_ops")
Cc: <stable@vger.kernel.org> [5.7+]
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/391319/
Signed-off-by: Christian König <christian.koenig@amd.com>
Fix W=1 compile warnings (invalid kerneldoc):
drivers/dma-buf/dma-buf.c:328: warning: Function parameter or member 'dmabuf' not described in 'dma_buf_set_name'
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200819175134.19261-1-krzk@kernel.org
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Merge v5.8-rc6 into drm-next
I've got a silent conflict + two trees based on fixes to merge.
Fixes a silent merge with amdgpu
Signed-off-by: Dave Airlie <airlied@redhat.com>
There exists a sleep-while-atomic bug while accessing the dmabuf->name
under mutex in the dmabuffs_dname(). This is caused from the SELinux
permissions checks on a process where it tries to validate the inherited
files from fork() by traversing them through iterate_fd() (which
traverse files under spin_lock) and call
match_file(security/selinux/hooks.c) where the permission checks happen.
This audit information is logged using dump_common_audit_data() where it
calls d_path() to get the file path name. If the file check happen on
the dmabuf's fd, then it ends up in ->dmabuffs_dname() and use mutex to
access dmabuf->name. The flow will be like below:
flush_unauthorized_files()
iterate_fd()
spin_lock() --> Start of the atomic section.
match_file()
file_has_perm()
avc_has_perm()
avc_audit()
slow_avc_audit()
common_lsm_audit()
dump_common_audit_data()
audit_log_d_path()
d_path()
dmabuffs_dname()
mutex_lock()--> Sleep while atomic.
Call trace captured (on 4.19 kernels) is below:
___might_sleep+0x204/0x208
__might_sleep+0x50/0x88
__mutex_lock_common+0x5c/0x1068
__mutex_lock_common+0x5c/0x1068
mutex_lock_nested+0x40/0x50
dmabuffs_dname+0xa0/0x170
d_path+0x84/0x290
audit_log_d_path+0x74/0x130
common_lsm_audit+0x334/0x6e8
slow_avc_audit+0xb8/0xf8
avc_has_perm+0x154/0x218
file_has_perm+0x70/0x180
match_file+0x60/0x78
iterate_fd+0x128/0x168
selinux_bprm_committing_creds+0x178/0x248
security_bprm_committing_creds+0x30/0x48
install_exec_creds+0x1c/0x68
load_elf_binary+0x3a4/0x14e0
search_binary_handler+0xb0/0x1e0
So, use spinlock to access dmabuf->name to avoid sleep-while-atomic.
Cc: <stable@vger.kernel.org> [5.3+]
Signed-off-by: Charan Teja Kalla <charante@codeaurora.org>
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Acked-by: Christian König <christian.koenig@amd.com>
[sumits: added comment to spinlock_t definition to avoid warning]
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/a83e7f0d-4e54-9848-4b58-e1acdbe06735@codeaurora.org
Cross-subsystem Changes:
- Improve dma-buf docs.
Core Changes:
- Add NV15, Q410, Q401 yuv formats.
- Add uncompressed AFBC modifier.
- Add DP helepr for reading Ignore MSA from DPCD.
- Add missing panel type for some panels
- Optimize drm/mm hole handling.
- Constify connector to infoframe functions.
- Add debugfs for VRR monitor range.
Driver Changes:
- Assorted small bugfixes in panfrost, malidp, panel/otm8009a.
- Convert tfp410 dt bindings to yaml, and rework time calculations.
- Add support for a few more simple panels.
- Cleanups and optimizations for ast.
- Allow adv7511 and simple-bridge to be used without connector creation.
- Cleanups to dw-hdmi function prototypes.
- Remove enabled bool from tiny/repaper and mipi-dbi, atomic handles it.
- Remove unused header file from dw-mipi-dsi
- Begin removing ttm_bo->offset.
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Merge tag 'drm-misc-next-2020-06-26' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
drm-misc-next for v5.9:
Cross-subsystem Changes:
- Improve dma-buf docs.
Core Changes:
- Add NV15, Q410, Q401 yuv formats.
- Add uncompressed AFBC modifier.
- Add DP helepr for reading Ignore MSA from DPCD.
- Add missing panel type for some panels
- Optimize drm/mm hole handling.
- Constify connector to infoframe functions.
- Add debugfs for VRR monitor range.
Driver Changes:
- Assorted small bugfixes in panfrost, malidp, panel/otm8009a.
- Convert tfp410 dt bindings to yaml, and rework time calculations.
- Add support for a few more simple panels.
- Cleanups and optimizations for ast.
- Allow adv7511 and simple-bridge to be used without connector creation.
- Cleanups to dw-hdmi function prototypes.
- Remove enabled bool from tiny/repaper and mipi-dbi, atomic handles it.
- Remove unused header file from dw-mipi-dsi
- Begin removing ttm_bo->offset.
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/b1e53620-7937-895c-bfcf-ed208be59c7c@linux.intel.com
Charan Teja reported a 'use-after-free' in dmabuffs_dname [1], which
happens if the dma_buf_release() is called while the userspace is
accessing the dma_buf pseudo fs's dmabuffs_dname() in another process,
and dma_buf_release() releases the dmabuf object when the last reference
to the struct file goes away.
I discussed with Arnd Bergmann, and he suggested that rather than tying
the dma_buf_release() to the file_operations' release(), we can tie it to
the dentry_operations' d_release(), which will be called when the last ref
to the dentry is removed.
The path exercised by __fput() calls f_op->release() first, and then calls
dput, which eventually calls d_op->d_release().
In the 'normal' case, when no userspace access is happening via dma_buf
pseudo fs, there should be exactly one fd, file, dentry and inode, so
closing the fd will kill of everything right away.
In the presented case, the dentry's d_release() will be called only when
the dentry's last ref is released.
Therefore, lets move dma_buf_release() from fops->release() to
d_ops->d_release()
Many thanks to Arnd for his FS insights :)
[1]: https://lore.kernel.org/patchwork/patch/1238278/
Fixes: bb2bb90304 ("dma-buf: add DMA_BUF_SET_NAME ioctls")
Reported-by: syzbot+3643a18836bce555bff6@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org> [5.3+]
Cc: Arnd Bergmann <arnd@arndb.de>
Reported-by: Charan Teja Reddy <charante@codeaurora.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Tested-by: Charan Teja Reddy <charante@codeaurora.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200611114418.19852-1-sumit.semwal@linaro.org
Just some tiny edits:
- fix link to struct dma_fence
- give slightly more meaningful title - the polling here is about
implicit fences, explicit fences (in sync_file or drm_syncobj) also
have their own polling
v2: I misplaced the .rst include change corresponding to this patch.
Reviewed-by: Thomas Hellstrom <thomas.hellstrom@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200612070535.1778368-1-daniel.vetter@ffwll.ch
Fix documentation warnings in dma-buf.[hc]:
../drivers/dma-buf/dma-buf.c:678: warning: Function parameter or member 'importer_ops' not described in 'dma_buf_dynamic_attach'
../drivers/dma-buf/dma-buf.c:678: warning: Function parameter or member 'importer_priv' not described in 'dma_buf_dynamic_attach'
../include/linux/dma-buf.h:339: warning: Incorrect use of kernel-doc format: * @move_notify
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/7bcbe6fe-0b4b-87da-d003-b68a26eb4cf0@infradead.org
Add a peer2peer flag noting that the importer can deal with device
resources which are not backed by pages.
Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/359286/
This makes the move_notify callback mandatory when the importer_ops are
provided. Since amdgpu is now migrated it doesn't make much sense
anymore to allow this.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/353995/?series=73646&rev=1
Instead use the pin() callback to detect dynamic DMA-buf handling.
Since amdgpu is now migrated it doesn't make much sense to keep
the extra flag.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/353997/?series=73646&rev=1
On the exporter side we add optional explicit pinning callbacks. Which are
called when the importer doesn't implement dynamic handling, move notification
or need the DMA-buf locked in place for its use case.
On the importer side we add an optional move_notify callback. This callback is
used by the exporter to inform the importers that their mappings should be
destroyed as soon as possible.
This allows the exporter to provide the mappings without the need to pin
the backing store.
v2: don't try to invalidate mappings when the callback is NULL,
lock the reservation obj while using the attachments,
add helper to set the callback
v3: move flag for invalidation support into the DMA-buf,
use new attach_info structure to set the callback
v4: use importer_priv field instead of mangling exporter priv.
v5: drop invalidation_supported flag
v6: squash together with pin/unpin changes
v7: pin/unpin takes an attachment now
v8: nuke dma_buf_attachment_(map|unmap)_locked,
everything is now handled backward compatible
v9: always cache when export/importer don't agree on dynamic handling
v10: minimal style cleanup
v11: drop automatically re-entry avoidance
v12: rename callback to move_notify
v13: add might_lock in appropriate places
v14: rebase on separated locking change
v15: add EXPERIMENTAL flag, some more code comments
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/353993/?series=73646&rev=1
UAPI Changes:
- Add support for DMA-BUF HEAPS.
Cross-subsystem Changes:
- mipi dsi definition updates, pulled into drm-intel as well.
- Add lockdep annotations for dma_resv vs mmap_sem and fs_reclaim.
- Remove support for dma-buf kmap/kunmap.
- Constify fb_ops in all fbdev drivers, including drm drivers and drm-core, and media as well.
Core Changes:
- Small cleanups to ttm.
- Fix SCDC definition.
- Assorted cleanups to core.
- Add todo to remove load/unload hooks, and use generic fbdev emulation.
- Assorted documentation updates.
- Use blocking ww lock in ttm fault handler.
- Remove drm_fb_helper_fbdev_setup/teardown.
- Warning fixes with W=1 for atomic.
- Use drm_debug_enabled() instead of drm_debug flag testing in various drivers.
- Fallback to nontiled mode in fbdev emulation when not all tiles are present. (Later on reverted)
- Various kconfig indentation fixes in core and drivers.
- Fix freeing transactions in dp-mst correctly.
- Sean Paul is steping down as core maintainer. :-(
- Add lockdep annotations for atomic locks vs dma-resv.
- Prevent use-after-free for a bad job in drm_scheduler.
- Fill out all block sizes in the P01x and P210 definitions.
- Avoid division by zero in drm/rect, and fix bounds.
- Add drm/rect selftests.
- Add aspect ratio and alternate clocks for HDMI 4k modes.
- Add todo for drm_framebuffer_funcs and fb_create cleanup.
- Drop DRM_AUTH for prime import/export ioctls.
- Clear DP-MST payload id tables downstream when initializating.
- Fix for DSC throughput definition.
- Add extra FEC definitions.
- Fix fake offset in drm_gem_object_funs.mmap.
- Stop using encoder->bridge in core directly
- Handle bridge chaining slightly better.
- Add backlight support to drm/panel, and use it in many panel drivers.
- Increase max number of y420 modes from 128 to 256, as preparation to add the new modes.
Driver Changes:
- Small fixes all over.
- Fix documentation in vkms.
- Fix mmap_sem vs dma_resv in nouveau.
- Small cleanup in komeda.
- Add page flip support in gma500 for psb/cdv.
- Add ddc symlink in the connector sysfs directory for many drivers.
- Add support for analogic an6345, and fix small bugs in it.
- Add atomic modesetting support to ast.
- Fix radeon fault handler VMA race.
- Switch udl to use generic shmem helpers.
- Unconditional vblank handling for mcde.
- Miscellaneous fixes to mcde.
- Tweak debug output from komeda using debugfs.
- Add gamma and color transform support to komeda for DOU-IPS.
- Add support for sony acx424AKP panel.
- Various small cleanups to gma500.
- Use generic fbdev emulation in udl, and replace udl_framebuffer with generic implementation.
- Add support for Logic PD Type 28 panel.
- Use drm_panel_* wrapper functions in exynos/tegra/msm.
- Add devicetree bindings for generic DSI panels.
- Don't include drm_pci.h directly in many drivers.
- Add support for begin/end_cpu_access in udmabuf.
- Stop using drm_get_pci_dev in gma500 and mga200.
- Fixes to UDL damage handling, and use dma_buf_begin/end_cpu_access.
- Add devfreq thermal support to panfrost.
- Fix hotplug with daisy chained monitors by removing VCPI when disabling topology manager.
- meson: Add support for OSD1 plane AFBC commit.
- Stop displaying garbage when toggling ast primary plane on/off.
- More cleanups and fixes to UDL.
- Add D32 suport to komeda.
- Remove globle copy of drm_dev in gma500.
- Add support for Boe Himax8279d MIPI-DSI LCD panel.
- Add support for ingenic JZ4770 panel.
- Small null pointer deference fix in ingenic.
- Remove support for the special tfp420 driver, as there is a generic way to do it.
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Merge tag 'drm-misc-next-2019-12-16' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
drm-misc-next for v5.6:
UAPI Changes:
- Add support for DMA-BUF HEAPS.
Cross-subsystem Changes:
- mipi dsi definition updates, pulled into drm-intel as well.
- Add lockdep annotations for dma_resv vs mmap_sem and fs_reclaim.
- Remove support for dma-buf kmap/kunmap.
- Constify fb_ops in all fbdev drivers, including drm drivers and drm-core, and media as well.
Core Changes:
- Small cleanups to ttm.
- Fix SCDC definition.
- Assorted cleanups to core.
- Add todo to remove load/unload hooks, and use generic fbdev emulation.
- Assorted documentation updates.
- Use blocking ww lock in ttm fault handler.
- Remove drm_fb_helper_fbdev_setup/teardown.
- Warning fixes with W=1 for atomic.
- Use drm_debug_enabled() instead of drm_debug flag testing in various drivers.
- Fallback to nontiled mode in fbdev emulation when not all tiles are present. (Later on reverted)
- Various kconfig indentation fixes in core and drivers.
- Fix freeing transactions in dp-mst correctly.
- Sean Paul is steping down as core maintainer. :-(
- Add lockdep annotations for atomic locks vs dma-resv.
- Prevent use-after-free for a bad job in drm_scheduler.
- Fill out all block sizes in the P01x and P210 definitions.
- Avoid division by zero in drm/rect, and fix bounds.
- Add drm/rect selftests.
- Add aspect ratio and alternate clocks for HDMI 4k modes.
- Add todo for drm_framebuffer_funcs and fb_create cleanup.
- Drop DRM_AUTH for prime import/export ioctls.
- Clear DP-MST payload id tables downstream when initializating.
- Fix for DSC throughput definition.
- Add extra FEC definitions.
- Fix fake offset in drm_gem_object_funs.mmap.
- Stop using encoder->bridge in core directly
- Handle bridge chaining slightly better.
- Add backlight support to drm/panel, and use it in many panel drivers.
- Increase max number of y420 modes from 128 to 256, as preparation to add the new modes.
Driver Changes:
- Small fixes all over.
- Fix documentation in vkms.
- Fix mmap_sem vs dma_resv in nouveau.
- Small cleanup in komeda.
- Add page flip support in gma500 for psb/cdv.
- Add ddc symlink in the connector sysfs directory for many drivers.
- Add support for analogic an6345, and fix small bugs in it.
- Add atomic modesetting support to ast.
- Fix radeon fault handler VMA race.
- Switch udl to use generic shmem helpers.
- Unconditional vblank handling for mcde.
- Miscellaneous fixes to mcde.
- Tweak debug output from komeda using debugfs.
- Add gamma and color transform support to komeda for DOU-IPS.
- Add support for sony acx424AKP panel.
- Various small cleanups to gma500.
- Use generic fbdev emulation in udl, and replace udl_framebuffer with generic implementation.
- Add support for Logic PD Type 28 panel.
- Use drm_panel_* wrapper functions in exynos/tegra/msm.
- Add devicetree bindings for generic DSI panels.
- Don't include drm_pci.h directly in many drivers.
- Add support for begin/end_cpu_access in udmabuf.
- Stop using drm_get_pci_dev in gma500 and mga200.
- Fixes to UDL damage handling, and use dma_buf_begin/end_cpu_access.
- Add devfreq thermal support to panfrost.
- Fix hotplug with daisy chained monitors by removing VCPI when disabling topology manager.
- meson: Add support for OSD1 plane AFBC commit.
- Stop displaying garbage when toggling ast primary plane on/off.
- More cleanups and fixes to UDL.
- Add D32 suport to komeda.
- Remove globle copy of drm_dev in gma500.
- Add support for Boe Himax8279d MIPI-DSI LCD panel.
- Add support for ingenic JZ4770 panel.
- Small null pointer deference fix in ingenic.
- Remove support for the special tfp420 driver, as there is a generic way to do it.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ba73535a-9334-5302-2e1f-5208bd7390bd@linux.intel.com
As part of the cleanup of some remaining y2038 issues, I came to
fs/compat_ioctl.c, which still has a couple of commands that need support
for time64_t.
In completely unrelated work, I spent time on cleaning up parts of this
file in the past, moving things out into drivers instead.
After Al Viro reviewed an earlier version of this series and did a lot
more of that cleanup, I decided to try to completely eliminate the rest
of it and move it all into drivers.
This series incorporates some of Al's work and many patches of my own,
but in the end stops short of actually removing the last part, which is
the scsi ioctl handlers. I have patches for those as well, but they need
more testing or possibly a rewrite.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Merge tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground
Pull removal of most of fs/compat_ioctl.c from Arnd Bergmann:
"As part of the cleanup of some remaining y2038 issues, I came to
fs/compat_ioctl.c, which still has a couple of commands that need
support for time64_t.
In completely unrelated work, I spent time on cleaning up parts of
this file in the past, moving things out into drivers instead.
After Al Viro reviewed an earlier version of this series and did a lot
more of that cleanup, I decided to try to completely eliminate the
rest of it and move it all into drivers.
This series incorporates some of Al's work and many patches of my own,
but in the end stops short of actually removing the last part, which
is the scsi ioctl handlers. I have patches for those as well, but they
need more testing or possibly a rewrite"
* tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (42 commits)
scsi: sd: enable compat ioctls for sed-opal
pktcdvd: add compat_ioctl handler
compat_ioctl: move SG_GET_REQUEST_TABLE handling
compat_ioctl: ppp: move simple commands into ppp_generic.c
compat_ioctl: handle PPPIOCGIDLE for 64-bit time_t
compat_ioctl: move PPPIOCSCOMPRESS to ppp_generic
compat_ioctl: unify copy-in of ppp filters
tty: handle compat PPP ioctls
compat_ioctl: move SIOCOUTQ out of compat_ioctl.c
compat_ioctl: handle SIOCOUTQNSD
af_unix: add compat_ioctl support
compat_ioctl: reimplement SG_IO handling
compat_ioctl: move WDIOC handling into wdt drivers
fs: compat_ioctl: move FITRIM emulation into file systems
gfs2: add compat_ioctl support
compat_ioctl: remove unused convert_in_user macro
compat_ioctl: remove last RAID handling code
compat_ioctl: remove /dev/raw ioctl translation
compat_ioctl: remove PCI ioctl translation
compat_ioctl: remove joystick ioctl translation
...
It's unused.
10 years ago, back when 32bit was still fairly common and trying to
not exhaust vmalloc space sounded like a worthwhile goal, adding these
to dma_buf made sense.
Reality is that they simply never caught on, and nowadays everyone who
needs plenty of buffers will run in 64bit mode anyway.
Also update the docs in this area to adjust them to reality.
The actual hooks in dma_buf_ops will be removed once all the
implementations are gone.
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Link: https://patchwork.freedesktop.org/patch/msgid/20191118103536.17675-10-daniel.vetter@ffwll.ch
The attachment list is now protected by the dma_resv object.
Stop holding the dma_buf->lock while calling ->attach/->detach,
this allows for concurrent attach/detach operations.
v2: cleanup commit message and locking in _debug_show()
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/336790
This patch is a stripped down version of the locking changes
necessary to support dynamic DMA-buf handling.
It adds a dynamic flag for both importers as well as exporters
so that drivers can choose if they want the reservation object
locked or unlocked during mapping of attachments.
For compatibility between drivers we cache the DMA-buf mapping
during attaching an importer as soon as exporter/importer
disagree on the dynamic handling.
Issues and solutions we considered:
- We can't change all existing drivers, and existing improters have
strong opinions about which locks they're holding while calling
dma_buf_attachment_map/unmap. Exporters also have strong opinions about
which locks they can acquire in their ->map/unmap callbacks, levaing no
room for change. The solution to avoid this was to move the
actual map/unmap out from this call, into the attach/detach callbacks,
and cache the mapping. This works because drivers don't call
attach/detach from deep within their code callchains (like deep in
memory management code called from cs/execbuf ioctl), but directly from
the fd2handle implementation.
- The caching has some troubles on some soc drivers, which set other modes
than DMA_BIDIRECTIONAL. We can't have 2 incompatible mappings, and we
can't re-create the mapping at _map time due to the above locking fun.
We very carefuly step around that by only caching at attach time if the
dynamic mode between importer/expoert mismatches.
- There's been quite some discussion on dma-buf mappings which need active
cache management, which would all break down when caching, plus we don't
have explicit flush operations on the attachment side. The solution to
this was to shrug and keep the current discrepancy between what the
dma-buf docs claim and what implementations do, with the hope that the
begin/end_cpu_access hooks are good enough and that all necessary
flushing to keep device mappings consistent will be done there.
v2: cleanup set_name merge, improve kerneldoc
v3: update commit message, kerneldoc and cleanup _debug_show()
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/336788/
The .ioctl and .compat_ioctl file operations have the same prototype so
they can both point to the same function, which works great almost all
the time when all the commands are compatible.
One exception is the s390 architecture, where a compat pointer is only
31 bit wide, and converting it into a 64-bit pointer requires calling
compat_ptr(). Most drivers here will never run in s390, but since we now
have a generic helper for it, it's easy enough to use it consistently.
I double-checked all these drivers to ensure that all ioctl arguments
are used as pointers or are ignored, but are not interpreted as integer
values.
Acked-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: David Sterba <dsterba@suse.com>
Acked-by: Darren Hart (VMware) <dvhart@infradead.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This reverts
67c97fb79a ("dma-buf: add reservation_object_fences helper")
dd7a7d1ff2 ("drm/i915: use new reservation_object_fences helper")
0e1d8083bd ("dma-buf: further relax reservation_object_add_shared_fence")
5d344f58da ("dma-buf: nuke reservation_object seq number")
The scenario that defeats simply grabbing a set of shared/exclusive
fences and using them blissfully under RCU is that any of those fences
may be reallocated by a SLAB_TYPESAFE_BY_RCU fence slab cache. In this
scenario, while keeping the rcu_read_lock we need to establish that no
fence was changed in the dma_resv after a read (or full) memory barrier.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190814182401.25009-1-chris@chris-wilson.co.uk
Be more consistent with the naming of the other DMA-buf objects.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/323401/
Add a new helper to get a consistent set of pointers from the reservation
object. While at it group all access helpers together in the header file.
v2: correctly return shared_count as well
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/322378/?series=64837&rev=1
Pull vfs mount updates from Al Viro:
"The first part of mount updates.
Convert filesystems to use the new mount API"
* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
mnt_init(): call shmem_init() unconditionally
constify ksys_mount() string arguments
don't bother with registering rootfs
init_rootfs(): don't bother with init_ramfs_fs()
vfs: Convert smackfs to use the new mount API
vfs: Convert selinuxfs to use the new mount API
vfs: Convert securityfs to use the new mount API
vfs: Convert apparmorfs to use the new mount API
vfs: Convert openpromfs to use the new mount API
vfs: Convert xenfs to use the new mount API
vfs: Convert gadgetfs to use the new mount API
vfs: Convert oprofilefs to use the new mount API
vfs: Convert ibmasmfs to use the new mount API
vfs: Convert qib_fs/ipathfs to use the new mount API
vfs: Convert efivarfs to use the new mount API
vfs: Convert configfs to use the new mount API
vfs: Convert binfmt_misc to use the new mount API
convenience helper: get_tree_single()
convenience helper get_tree_nodev()
vfs: Kill sget_userns()
...
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not see http www gnu org
licenses
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 503 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The show_fdinfo handler exports the same information available through
debugfs on a per-buffer basis.
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Chenbo Feng <fengc@google.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613223408.139221-4-fengc@google.com
This patch adds complimentary DMA_BUF_SET_NAME ioctls, which lets
userspace processes attach a free-form name to each buffer.
This information can be extremely helpful for tracking and accounting
shared buffers. For example, on Android, we know what each buffer will
be used for at allocation time: GL, multimedia, camera, etc. The
userspace allocator can use DMA_BUF_SET_NAME to associate that
information with the buffer, so we can later give developers a
breakdown of how much memory they're allocating for graphics, camera,
etc.
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Chenbo Feng <fengc@google.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613223408.139221-3-fengc@google.com
By traversing /proc/*/fd and /proc/*/map_files, processes with CAP_ADMIN
can get a lot of fine-grained data about how shmem buffers are shared
among processes. stat(2) on each entry gives the caller a unique
ID (st_ino), the buffer's size (st_size), and even the number of pages
currently charged to the buffer (st_blocks / 512).
In contrast, all dma-bufs share the same anonymous inode. So while we
can count how many dma-buf fds or mappings a process has, we can't get
the size of the backing buffers or tell if two entries point to the same
dma-buf. On systems with debugfs, we can get a per-buffer breakdown of
size and reference count, but can't tell which processes are actually
holding the references to each buffer.
Replace the singleton inode with full-fledged inodes allocated by
alloc_anon_inode(). This involves creating and mounting a
mini-pseudo-filesystem for dma-buf, following the example in fs/aio.c.
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Chenbo Feng <fengc@google.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613223408.139221-2-fengc@google.com
To allow a smooth transition from pinning buffer objects to dynamic
invalidation we first start to cache the sg_table for an attachment.
v2: keep closer to the DRM implementation
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.kernel.org/patch/10943053/
The docs state the callback is optional but it is not, make it optional.
Signed-off-by: Andrew F. Davis <afd@ti.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190329165201.16233-1-afd@ti.com
Since commit 9ea0dfbf972 ("dma-buf: make map_atomic and map function
pointers optional"), the core provides the no-op functions when map and
map_atomic are not provided, so we no longer need assert that are
supplied by a dma-buf exporter.
Fixes: 09ea0dfbf9 ("dma-buf: make map_atomic and map function pointers optional")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20180807183647.22626-1-chris@chris-wilson.co.uk
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Neither used nor correctly implemented anywhere. Just completely remove
the interface.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/226645/
Daniel Vetter