Hello Christian,
On 5/30/22 09:50, Christian König wrote:
Hi Dmitry,I assume all the patches will go via the DRM tree in the end since the
First of all please separate out this patch from the rest of the series,
since this is a complex separate structural change.
rest of the DRM patches in this series depend on this dma-buf change.
But I see that separation may ease reviewing of the dma-buf changes, so
let's try it.
I have tried this before and failed because catching all the locks inSure, I'll fix up all the reported things in the next iteration.
the right code paths are very tricky. So expect some fallout from this
and make sure the kernel test robot and CI systems are clean.
BTW, have you ever posted yours version of the patch? Will be great if
we could compare the changed code paths.
Do we really want to move all the locks to the importers? Seems theThis patch introduces new locking convention for dma-buf users. From nowInstead of adding new locked variants please mark all variants which
on all dma-buf importers are responsible for holding dma-buf reservation
lock around operations performed over dma-bufs.
This patch implements the new dma-buf locking convention by:
1. Making dma-buf API functions to take the reservation lock.
2. Adding new locked variants of the dma-buf API functions for drivers
that need to manage imported dma-bufs under the held lock.
expect to be called without a lock with an _unlocked postfix.
This should make it easier to remove those in a follow up patch set and
then fully move the locking into the importer.
majority of drivers should be happy with the dma-buf helpers handling
the locking for them.
Radeon and Nouveau use gem_prime_import_sg_table() and they take resv3. Converting all drivers to the new locking scheme.I have strong doubts that you got all of them. At least radeon and
nouveau should grab the reservation lock in their ->attach callbacks
somehow.
lock already, seems they should be okay (?)
I assume all the basics should covered in this v6. At minimum Intel,
Tegra, Panfrost, Lima and Rockchip drivers should be good. If I missed
something, then please let me know and I'll correct it.
AlrightSigned-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>Please make removing dmabuf->lock a separate change.
---
drivers/dma-buf/dma-buf.c | 270 +++++++++++-------
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 6 +-
drivers/gpu/drm/drm_client.c | 4 +-
drivers/gpu/drm/drm_gem.c | 33 +++
drivers/gpu/drm/drm_gem_framebuffer_helper.c | 6 +-
drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c | 10 +-
drivers/gpu/drm/qxl/qxl_object.c | 17 +-
drivers/gpu/drm/qxl/qxl_prime.c | 4 +-
.../common/videobuf2/videobuf2-dma-contig.c | 11 +-
.../media/common/videobuf2/videobuf2-dma-sg.c | 11 +-
.../common/videobuf2/videobuf2-vmalloc.c | 11 +-
include/drm/drm_gem.h | 3 +
include/linux/dma-buf.h | 14 +-
13 files changed, 241 insertions(+), 159 deletions(-)
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index 32f55640890c..64a9909ccfa2 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -552,7 +552,6 @@ struct dma_buf *dma_buf_export(const struct
dma_buf_export_info *exp_info)
file->f_mode |= FMODE_LSEEK;
dmabuf->file = file;
- mutex_init(&dmabuf->lock);