Linaro-mm-sig April 2025

linaro-mm-sig@lists.linaro.org

7 participants
13 discussions

[PATCH RFC 00/12] dma: Enable dmem cgroup tracking

by Maxime Ripard

Hi, Here's preliminary work to enable dmem tracking for heavy users of DMA allocations on behalf of userspace: v4l2, DRM, and dma-buf heaps. It's not really meant for inclusion at the moment, because I really don't like it that much, and would like to discuss solutions on how to make it nicer. In particular, the dma dmem region accessors don't feel that great to me. It duplicates the logic to select the proper accessor in dma_alloc_attrs(), and it looks fragile and potentially buggy to me. One solution I tried is to do the accounting in dma_alloc_attrs() directly, depending on a flag being set, similar to what __GFP_ACCOUNT is doing. It didn't work because dmem initialises a state pointer when charging an allocation to a region, and expects that state pointer to be passed back when uncharging. Since dma_alloc_attrs() returns a void pointer to the allocated buffer, we need to put that state into a higher-level structure, such as drm_gem_object, or dma_buf. Since we can't share the region selection logic, we need to get the region through some other mean. Another thing I consider was to return the region as part of the allocated buffer (through struct page or folio), but those are lost across the calls and dma_alloc_attrs() will only get a void pointer. So that's not doable without some heavy rework, if it's a good idea at all. So yeah, I went for the dumbest possible solution with the accessors, hoping you could suggest a much smarter idea :) Thanks, Maxime Signed-off-by: Maxime Ripard <mripard(a)kernel.org> --- Maxime Ripard (12): cma: Register dmem region for each cma region cma: Provide accessor to cma dmem region dma: coherent: Register dmem region for each coherent region dma: coherent: Provide accessor to dmem region dma: contiguous: Provide accessor to dmem region dma: direct: Provide accessor to dmem region dma: Create default dmem region for DMA allocations dma: Provide accessor to dmem region dma-buf: Clear cgroup accounting on release dma-buf: cma: Account for allocations in dmem cgroup drm/gem: Add cgroup memory accounting media: videobuf2: Track buffer allocations through the dmem cgroup drivers/dma-buf/dma-buf.c | 7 ++++ drivers/dma-buf/heaps/cma_heap.c | 18 ++++++++-- drivers/gpu/drm/drm_gem.c | 5 +++ drivers/gpu/drm/drm_gem_dma_helper.c | 6 ++++ .../media/common/videobuf2/videobuf2-dma-contig.c | 19 +++++++++++ include/drm/drm_device.h | 1 + include/drm/drm_gem.h | 2 ++ include/linux/cma.h | 9 +++++ include/linux/dma-buf.h | 5 +++ include/linux/dma-direct.h | 2 ++ include/linux/dma-map-ops.h | 32 ++++++++++++++++++ include/linux/dma-mapping.h | 11 ++++++ kernel/dma/coherent.c | 26 +++++++++++++++ kernel/dma/direct.c | 8 +++++ kernel/dma/mapping.c | 39 ++++++++++++++++++++++ mm/cma.c | 21 +++++++++++- mm/cma.h | 3 ++ 17 files changed, 211 insertions(+), 3 deletions(-) --- base-commit: 55a2aa61ba59c138bd956afe0376ec412a7004cf change-id: 20250307-dmem-cgroups-73febced0989 Best regards, -- Maxime Ripard <mripard(a)kernel.org>

2 hours, 53 minutes

Re: [PATCH v2] drm/nouveau: Prevent signalled fences in pending list

by Christian König

Am 03.04.25 um 15:15 schrieb Danilo Krummrich: > On Thu, Apr 03, 2025 at 02:58:13PM +0200, Philipp Stanner wrote: >> On Thu, 2025-04-03 at 14:08 +0200, Christian König wrote: >>> Am 03.04.25 um 12:13 schrieb Philipp Stanner: >>> BTW: nouveau_fence_no_signaling() looks completely broken as well. It >>> calls nouveau_fence_is_signaled() and then list_del() on the fence >>> head. >> I can assure you that a great many things in Nouveau look completely >> broken. >> >> The question for us is always the cost-benefit-ratio when fixing bugs. >> There are fixes that solve the bug with reasonable effort, and there >> are great reworks towards an ideal state. > That's just an additional thing that Christian noticed. It isn't really directly > related to what you want to fix with your patch. Well there is some relation. From nouveau_fence_no_signaling(): if (nouveau_fence_is_signaled(f)) { list_del(&fence->head); dma_fence_put(&fence->base); return false; } That looks like somebody realized that the fence needs to be removed from the pending list and the reference dropped. It's just that this was added to the wrong function, e.g. those lines need to be in nouveau_fence_is_signaled() and not here. Regards, Christian. > > I think the function can simply be dropped.

5 hours, 19 minutes

Re: [PATCH v2] drm/nouveau: Prevent signalled fences in pending list

by Christian König

Am 03.04.25 um 14:58 schrieb Philipp Stanner: > On Thu, 2025-04-03 at 14:08 +0200, Christian König wrote: >> Am 03.04.25 um 12:13 schrieb Philipp Stanner: >>> Nouveau currently relies on the assumption that dma_fences will >>> only >>> ever get signalled through nouveau_fence_signal(), which takes care >>> of >>> removing a signalled fence from the list >>> nouveau_fence_chan.pending. >>> >>> This self-imposed rule is violated in nouveau_fence_done(), where >>> dma_fence_is_signaled() can signal the fence without removing it >>> from >>> the list. This enables accesses to already signalled fences through >>> the >>> list, which is a bug. >>> >>> Furthermore, it must always be possible to use standard dma_fence >>> methods an a dma_fence and observe valid behavior. The canonical >>> way of >>> ensuring that signalling a fence has additional effects is to add >>> those >>> effects to a callback and register it on that fence. >>> >>> Move the code from nouveau_fence_signal() into a dma_fence >>> callback. >>> Register that callback when creating the fence. >>> >>> Cc: <stable(a)vger.kernel.org> # 4.10+ >>> Signed-off-by: Philipp Stanner <phasta(a)kernel.org> >>> --- >>> Changes in v2: >>> - Remove Fixes: tag. (Danilo) >>> - Remove integer "drop" and call nvif_event_block() in the fence >>> callback. (Danilo) >>> --- >>> drivers/gpu/drm/nouveau/nouveau_fence.c | 52 +++++++++++++-------- >>> ---- >>> drivers/gpu/drm/nouveau/nouveau_fence.h | 1 + >>> 2 files changed, 29 insertions(+), 24 deletions(-) >>> >>> diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.c >>> b/drivers/gpu/drm/nouveau/nouveau_fence.c >>> index 7cc84472cece..cf510ef9641a 100644 >>> --- a/drivers/gpu/drm/nouveau/nouveau_fence.c >>> +++ b/drivers/gpu/drm/nouveau/nouveau_fence.c >>> @@ -50,24 +50,24 @@ nouveau_fctx(struct nouveau_fence *fence) >>> return container_of(fence->base.lock, struct >>> nouveau_fence_chan, lock); >>> } >>> >>> -static int >>> -nouveau_fence_signal(struct nouveau_fence *fence) >>> +static void >>> +nouveau_fence_cleanup_cb(struct dma_fence *dfence, struct >>> dma_fence_cb *cb) >>> { >>> - int drop = 0; >>> + struct nouveau_fence_chan *fctx; >>> + struct nouveau_fence *fence; >>> + >>> + fence = container_of(dfence, struct nouveau_fence, base); >>> + fctx = nouveau_fctx(fence); >>> >>> - dma_fence_signal_locked(&fence->base); >>> list_del(&fence->head); >>> rcu_assign_pointer(fence->channel, NULL); >>> >>> if (test_bit(DMA_FENCE_FLAG_USER_BITS, &fence- >>>> base.flags)) { >>> - struct nouveau_fence_chan *fctx = >>> nouveau_fctx(fence); >>> - >>> if (!--fctx->notify_ref) >>> - drop = 1; >>> + nvif_event_block(&fctx->event); >>> } >>> >>> dma_fence_put(&fence->base); >>> - return drop; >>> } >>> >>> static struct nouveau_fence * >>> @@ -93,8 +93,7 @@ nouveau_fence_context_kill(struct >>> nouveau_fence_chan *fctx, int error) >>> if (error) >>> dma_fence_set_error(&fence->base, error); >>> >>> - if (nouveau_fence_signal(fence)) >>> - nvif_event_block(&fctx->event); >>> + dma_fence_signal_locked(&fence->base); >>> } >>> fctx->killed = 1; >>> spin_unlock_irqrestore(&fctx->lock, flags); >>> @@ -127,11 +126,10 @@ nouveau_fence_context_free(struct >>> nouveau_fence_chan *fctx) >>> kref_put(&fctx->fence_ref, nouveau_fence_context_put); >>> } >>> >>> -static int >>> +static void >>> nouveau_fence_update(struct nouveau_channel *chan, struct >>> nouveau_fence_chan *fctx) >>> { >>> struct nouveau_fence *fence; >>> - int drop = 0; >>> u32 seq = fctx->read(chan); >>> >>> while (!list_empty(&fctx->pending)) { >>> @@ -140,10 +138,8 @@ nouveau_fence_update(struct nouveau_channel >>> *chan, struct nouveau_fence_chan *fc >>> if ((int)(seq - fence->base.seqno) < 0) >>> break; >>> >>> - drop |= nouveau_fence_signal(fence); >>> + dma_fence_signal_locked(&fence->base); >>> } >>> - >>> - return drop; >>> } >>> >>> static void >>> @@ -152,7 +148,6 @@ nouveau_fence_uevent_work(struct work_struct >>> *work) >>> struct nouveau_fence_chan *fctx = container_of(work, >>> struct nouveau_fence_chan, >>> >>> uevent_work); >>> unsigned long flags; >>> - int drop = 0; >>> >>> spin_lock_irqsave(&fctx->lock, flags); >>> if (!list_empty(&fctx->pending)) { >>> @@ -161,11 +156,8 @@ nouveau_fence_uevent_work(struct work_struct >>> *work) >>> >>> fence = list_entry(fctx->pending.next, >>> typeof(*fence), head); >>> chan = rcu_dereference_protected(fence->channel, >>> lockdep_is_held(&fctx->lock)); >>> - if (nouveau_fence_update(chan, fctx)) >>> - drop = 1; >>> + nouveau_fence_update(chan, fctx); >>> } >>> - if (drop) >>> - nvif_event_block(&fctx->event); >>> >>> spin_unlock_irqrestore(&fctx->lock, flags); >>> } >>> @@ -235,6 +227,19 @@ nouveau_fence_emit(struct nouveau_fence >>> *fence) >>> &fctx->lock, fctx->context, ++fctx- >>>> sequence); >>> kref_get(&fctx->fence_ref); >>> >>> + fence->cb.func = nouveau_fence_cleanup_cb; >>> + /* Adding a callback runs into >>> __dma_fence_enable_signaling(), which will >>> + * ultimately run into nouveau_fence_no_signaling(), where >>> a WARN_ON >>> + * would fire because the refcount can be dropped there. >>> + * >>> + * Increment the refcount here temporarily to work around >>> that. >>> + */ >>> + dma_fence_get(&fence->base); >>> + ret = dma_fence_add_callback(&fence->base, &fence->cb, >>> nouveau_fence_cleanup_cb); >> That looks like a really really awkward approach. The driver >> basically uses a the DMA fence infrastructure as middle layer and >> callbacks into itself to cleanup it's own structures. > What else are callbacks good for, if not to do something automatically > when the fence gets signaled? Well if you add a callback for a signal you issued yourself then that's kind of awkward. E.g. you call into the DMA fence code, just for the DMA fence code to call yourself back again. >> Additional to that we don't guarantee any callback order for the DMA >> fence and so it can be that mix cleaning up the callback with other >> work which is certainly not good when you want to guarantee that the >> cleanup happens under the same lock. > Isn't my perception correct that the primary issue you have with this > approach is that dma_fence_put() is called from within the callback? Or > do you also take issue with deleting from the list? Well kind of both. The issue is that the caller of dma_fence_signal() or dma_fence_signal_locked() must hold the reference until the function returns. When you do the list cleanup and the drop inside the callback it is perfectly possible that the fence pointer becomes stale before you return and that's really not a good idea. > >> Instead the call to dma_fence_signal_locked() should probably be >> removed from nouveau_fence_signal() and into >> nouveau_fence_context_kill() and nouveau_fence_update(). >> >> This way nouveau_fence_is_signaled() can call this function as well. > Which "this function"? dma_fence_signal_locked() No the cleanup function for the list entry. Whatever you call that then, the name nouveau_fence_signal() is probably not appropriate any more. > >> BTW: nouveau_fence_no_signaling() looks completely broken as well. It >> calls nouveau_fence_is_signaled() and then list_del() on the fence >> head. > I can assure you that a great many things in Nouveau look completely > broken. > > The question for us is always the cost-benefit-ratio when fixing bugs. > There are fixes that solve the bug with reasonable effort, and there > are great reworks towards an ideal state. I would just simply drop that function. As far as I can see it severs no purpose other than doing exactly what the common DMA fence code does anyway. Just one less thing which could fail. Christian. > > P. > > >> As far as I can see that is completely superfluous and should >> probably be dropped. IIRC I once had a patch to clean that up but it >> was dropped for some reason. >> >> Regards, >> Christian. >> >> >>> + dma_fence_put(&fence->base); >>> + if (ret) >>> + return ret; >>> + >>> ret = fctx->emit(fence); >>> if (!ret) { >>> dma_fence_get(&fence->base); >>> @@ -246,8 +251,7 @@ nouveau_fence_emit(struct nouveau_fence *fence) >>> return -ENODEV; >>> } >>> >>> - if (nouveau_fence_update(chan, fctx)) >>> - nvif_event_block(&fctx->event); >>> + nouveau_fence_update(chan, fctx); >>> >>> list_add_tail(&fence->head, &fctx->pending); >>> spin_unlock_irq(&fctx->lock); >>> @@ -270,8 +274,8 @@ nouveau_fence_done(struct nouveau_fence *fence) >>> >>> spin_lock_irqsave(&fctx->lock, flags); >>> chan = rcu_dereference_protected(fence->channel, >>> lockdep_is_held(&fctx->lock)); >>> - if (chan && nouveau_fence_update(chan, fctx)) >>> - nvif_event_block(&fctx->event); >>> + if (chan) >>> + nouveau_fence_update(chan, fctx); >>> spin_unlock_irqrestore(&fctx->lock, flags); >>> } >>> return dma_fence_is_signaled(&fence->base); >>> diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.h >>> b/drivers/gpu/drm/nouveau/nouveau_fence.h >>> index 8bc065acfe35..e6b2df7fdc42 100644 >>> --- a/drivers/gpu/drm/nouveau/nouveau_fence.h >>> +++ b/drivers/gpu/drm/nouveau/nouveau_fence.h >>> @@ -10,6 +10,7 @@ struct nouveau_bo; >>> >>> struct nouveau_fence { >>> struct dma_fence base; >>> + struct dma_fence_cb cb; >>> >>> struct list_head head; >>>

5 hours, 30 minutes

Re: [PATCH v2] drm/nouveau: Prevent signalled fences in pending list

by Christian König

Am 03.04.25 um 12:25 schrieb Danilo Krummrich: > On Thu, Apr 03, 2025 at 12:17:29PM +0200, Philipp Stanner wrote: >> On Thu, 2025-04-03 at 12:13 +0200, Philipp Stanner wrote: >>> -static int >>> -nouveau_fence_signal(struct nouveau_fence *fence) >>> +static void >>> +nouveau_fence_cleanup_cb(struct dma_fence *dfence, struct >>> dma_fence_cb *cb) >>> { >>> - int drop = 0; >>> + struct nouveau_fence_chan *fctx; >>> + struct nouveau_fence *fence; >>> + >>> + fence = container_of(dfence, struct nouveau_fence, base); >>> + fctx = nouveau_fctx(fence); >>> >>> - dma_fence_signal_locked(&fence->base); >>> list_del(&fence->head); >>> rcu_assign_pointer(fence->channel, NULL); >>> >>> if (test_bit(DMA_FENCE_FLAG_USER_BITS, &fence->base.flags)) >>> { >>> - struct nouveau_fence_chan *fctx = >>> nouveau_fctx(fence); >>> - >>> if (!--fctx->notify_ref) >>> - drop = 1; >>> + nvif_event_block(&fctx->event); >>> } >>> >>> dma_fence_put(&fence->base); >> What I realized while coding this v2 is that we might want to think >> about whether we really want the dma_fence_put() in the fence callback? >> >> It should work fine, since it's exactly identical to the previous >> code's behavior – but effectively it means that the driver's reference >> will be dropped whenever it signals that fence. > Not quite, it's the reference of the fence context's pending list. > > When the fence is emitted, dma_fence_init() is called, which initializes the > reference count to 1. Subsequently, another reference is taken, when the fence > is added to the pending list. Once the fence is signaled and hence removed from > the pending list, we can (and have to) drop this reference. The general idea is that the caller must hold the reference until the signaling is completed. So for signaling from the interrupt handler it means that you need to call dma_fence_put() for the list reference *after* you called dma_fence_signal_locked(). For signaling from the .enable_signaling or .signaled callback you need to remove the fence from the linked list and call dma_fence_put() *before* you return (because the caller is holding the potential last reference). That's why I'm pretty sure that the approach with installing the callback won't work. As far as I know no other DMA fence implementation is doing that. Regards, Christian.

6 hours, 18 minutes

Re: [PATCH v2] drm/nouveau: Prevent signalled fences in pending list

by Christian König

Am 03.04.25 um 12:13 schrieb Philipp Stanner: > Nouveau currently relies on the assumption that dma_fences will only > ever get signalled through nouveau_fence_signal(), which takes care of > removing a signalled fence from the list nouveau_fence_chan.pending. > > This self-imposed rule is violated in nouveau_fence_done(), where > dma_fence_is_signaled() can signal the fence without removing it from > the list. This enables accesses to already signalled fences through the > list, which is a bug. > > Furthermore, it must always be possible to use standard dma_fence > methods an a dma_fence and observe valid behavior. The canonical way of > ensuring that signalling a fence has additional effects is to add those > effects to a callback and register it on that fence. > > Move the code from nouveau_fence_signal() into a dma_fence callback. > Register that callback when creating the fence. > > Cc: <stable(a)vger.kernel.org> # 4.10+ > Signed-off-by: Philipp Stanner <phasta(a)kernel.org> > --- > Changes in v2: > - Remove Fixes: tag. (Danilo) > - Remove integer "drop" and call nvif_event_block() in the fence > callback. (Danilo) > --- > drivers/gpu/drm/nouveau/nouveau_fence.c | 52 +++++++++++++------------ > drivers/gpu/drm/nouveau/nouveau_fence.h | 1 + > 2 files changed, 29 insertions(+), 24 deletions(-) > > diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.c b/drivers/gpu/drm/nouveau/nouveau_fence.c > index 7cc84472cece..cf510ef9641a 100644 > --- a/drivers/gpu/drm/nouveau/nouveau_fence.c > +++ b/drivers/gpu/drm/nouveau/nouveau_fence.c > @@ -50,24 +50,24 @@ nouveau_fctx(struct nouveau_fence *fence) > return container_of(fence->base.lock, struct nouveau_fence_chan, lock); > } > > -static int > -nouveau_fence_signal(struct nouveau_fence *fence) > +static void > +nouveau_fence_cleanup_cb(struct dma_fence *dfence, struct dma_fence_cb *cb) > { > - int drop = 0; > + struct nouveau_fence_chan *fctx; > + struct nouveau_fence *fence; > + > + fence = container_of(dfence, struct nouveau_fence, base); > + fctx = nouveau_fctx(fence); > > - dma_fence_signal_locked(&fence->base); > list_del(&fence->head); > rcu_assign_pointer(fence->channel, NULL); > > if (test_bit(DMA_FENCE_FLAG_USER_BITS, &fence->base.flags)) { > - struct nouveau_fence_chan *fctx = nouveau_fctx(fence); > - > if (!--fctx->notify_ref) > - drop = 1; > + nvif_event_block(&fctx->event); > } > > dma_fence_put(&fence->base); > - return drop; > } > > static struct nouveau_fence * > @@ -93,8 +93,7 @@ nouveau_fence_context_kill(struct nouveau_fence_chan *fctx, int error) > if (error) > dma_fence_set_error(&fence->base, error); > > - if (nouveau_fence_signal(fence)) > - nvif_event_block(&fctx->event); > + dma_fence_signal_locked(&fence->base); > } > fctx->killed = 1; > spin_unlock_irqrestore(&fctx->lock, flags); > @@ -127,11 +126,10 @@ nouveau_fence_context_free(struct nouveau_fence_chan *fctx) > kref_put(&fctx->fence_ref, nouveau_fence_context_put); > } > > -static int > +static void > nouveau_fence_update(struct nouveau_channel *chan, struct nouveau_fence_chan *fctx) > { > struct nouveau_fence *fence; > - int drop = 0; > u32 seq = fctx->read(chan); > > while (!list_empty(&fctx->pending)) { > @@ -140,10 +138,8 @@ nouveau_fence_update(struct nouveau_channel *chan, struct nouveau_fence_chan *fc > if ((int)(seq - fence->base.seqno) < 0) > break; > > - drop |= nouveau_fence_signal(fence); > + dma_fence_signal_locked(&fence->base); > } > - > - return drop; > } > > static void > @@ -152,7 +148,6 @@ nouveau_fence_uevent_work(struct work_struct *work) > struct nouveau_fence_chan *fctx = container_of(work, struct nouveau_fence_chan, > uevent_work); > unsigned long flags; > - int drop = 0; > > spin_lock_irqsave(&fctx->lock, flags); > if (!list_empty(&fctx->pending)) { > @@ -161,11 +156,8 @@ nouveau_fence_uevent_work(struct work_struct *work) > > fence = list_entry(fctx->pending.next, typeof(*fence), head); > chan = rcu_dereference_protected(fence->channel, lockdep_is_held(&fctx->lock)); > - if (nouveau_fence_update(chan, fctx)) > - drop = 1; > + nouveau_fence_update(chan, fctx); > } > - if (drop) > - nvif_event_block(&fctx->event); > > spin_unlock_irqrestore(&fctx->lock, flags); > } > @@ -235,6 +227,19 @@ nouveau_fence_emit(struct nouveau_fence *fence) > &fctx->lock, fctx->context, ++fctx->sequence); > kref_get(&fctx->fence_ref); > > + fence->cb.func = nouveau_fence_cleanup_cb; > + /* Adding a callback runs into __dma_fence_enable_signaling(), which will > + * ultimately run into nouveau_fence_no_signaling(), where a WARN_ON > + * would fire because the refcount can be dropped there. > + * > + * Increment the refcount here temporarily to work around that. > + */ > + dma_fence_get(&fence->base); > + ret = dma_fence_add_callback(&fence->base, &fence->cb, nouveau_fence_cleanup_cb); That looks like a really really awkward approach. The driver basically uses a the DMA fence infrastructure as middle layer and callbacks into itself to cleanup it's own structures. Additional to that we don't guarantee any callback order for the DMA fence and so it can be that mix cleaning up the callback with other work which is certainly not good when you want to guarantee that the cleanup happens under the same lock. Instead the call to dma_fence_signal_locked() should probably be removed from nouveau_fence_signal() and into nouveau_fence_context_kill() and nouveau_fence_update(). This way nouveau_fence_is_signaled() can call this function as well. BTW: nouveau_fence_no_signaling() looks completely broken as well. It calls nouveau_fence_is_signaled() and then list_del() on the fence head. As far as I can see that is completely superfluous and should probably be dropped. IIRC I once had a patch to clean that up but it was dropped for some reason. Regards, Christian. > + dma_fence_put(&fence->base); > + if (ret) > + return ret; > + > ret = fctx->emit(fence); > if (!ret) { > dma_fence_get(&fence->base); > @@ -246,8 +251,7 @@ nouveau_fence_emit(struct nouveau_fence *fence) > return -ENODEV; > } > > - if (nouveau_fence_update(chan, fctx)) > - nvif_event_block(&fctx->event); > + nouveau_fence_update(chan, fctx); > > list_add_tail(&fence->head, &fctx->pending); > spin_unlock_irq(&fctx->lock); > @@ -270,8 +274,8 @@ nouveau_fence_done(struct nouveau_fence *fence) > > spin_lock_irqsave(&fctx->lock, flags); > chan = rcu_dereference_protected(fence->channel, lockdep_is_held(&fctx->lock)); > - if (chan && nouveau_fence_update(chan, fctx)) > - nvif_event_block(&fctx->event); > + if (chan) > + nouveau_fence_update(chan, fctx); > spin_unlock_irqrestore(&fctx->lock, flags); > } > return dma_fence_is_signaled(&fence->base); > diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.h b/drivers/gpu/drm/nouveau/nouveau_fence.h > index 8bc065acfe35..e6b2df7fdc42 100644 > --- a/drivers/gpu/drm/nouveau/nouveau_fence.h > +++ b/drivers/gpu/drm/nouveau/nouveau_fence.h > @@ -10,6 +10,7 @@ struct nouveau_bo; > > struct nouveau_fence { > struct dma_fence base; > + struct dma_fence_cb cb; > > struct list_head head; >

6 hours, 32 minutes

[PATCH v2 0/2] dma-buf: heaps: Support carved-out heaps

by Maxime Ripard

Hi, This series is the follow-up of the discussion that John and I had some time ago here: https://lore.kernel.org/all/CANDhNCquJn6bH3KxKf65BWiTYLVqSd9892-xtFDHHqqyrr… The initial problem we were discussing was that I'm currently working on a platform which has a memory layout with ECC enabled. However, enabling the ECC has a number of drawbacks on that platform: lower performance, increased memory usage, etc. So for things like framebuffers, the trade-off isn't great and thus there's a memory region with ECC disabled to allocate from for such use cases. After a suggestion from John, I chose to first start using heap allocations flags to allow for userspace to ask for a particular ECC setup. This is then backed by a new heap type that runs from reserved memory chunks flagged as such, and the existing DT properties to specify the ECC properties. After further discussion, it was considered that flags were not the right solution, and relying on the names of the heaps would be enough to let userspace know the kind of buffer it deals with. Thus, even though the uAPI part of it has been dropped in this second version, we still need a driver to create heaps out of carved-out memory regions. In addition to the original usecase, a similar driver can be found in BSPs from most vendors, so I believe it would be a useful addition to the kernel. I submitted a draft PR to the DT schema for the bindings used in this PR: https://github.com/devicetree-org/dt-schema/pull/138 Let me know what you think, Maxime Signed-off-by: Maxime Ripard <mripard(a)kernel.org> --- Changes in v2: - Add vmap/vunmap operations - Drop ECC flags uapi - Rebase on top of 6.14 - Link to v1: https://lore.kernel.org/r/20240515-dma-buf-ecc-heap-v1-0-54cbbd049511@kerne… --- Maxime Ripard (2): dma-buf: heaps: system: Remove global variable dma-buf: heaps: Introduce a new heap for reserved memory drivers/dma-buf/heaps/Kconfig | 8 + drivers/dma-buf/heaps/Makefile | 1 + drivers/dma-buf/heaps/carveout_heap.c | 360 ++++++++++++++++++++++++++++++++++ drivers/dma-buf/heaps/system_heap.c | 17 +- 4 files changed, 381 insertions(+), 5 deletions(-) --- base-commit: fcbf30774e82a441890b722bf0c26542fb82150f change-id: 20240515-dma-buf-ecc-heap-28a311d2c94e Best regards, -- Maxime Ripard <mripard(a)kernel.org>

11 hours, 36 minutes

[PATCH v6] drm/syncobj: Extend EXPORT_SYNC_FILE for timeline syncobjs

by Rob Clark

From: Rob Clark <robdclark(a)chromium.org> Add support for exporting a dma_fence fd for a specific point on a timeline. This is needed for vtest/vpipe[1][2] to implement timeline syncobj support, as it needs a way to turn a point on a timeline back into a dma_fence fd. It also closes an odd omission from the syncobj UAPI. [1] https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33433 [2] https://gitlab.freedesktop.org/virgl/virglrenderer/-/merge_requests/805 v2: Add DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE v3: Add unstaged uabi header hunk v4: Also handle IMPORT_SYNC_FILE case v5: Address comments from Dmitry v6: checkpatch.pl nits Signed-off-by: Rob Clark <robdclark(a)chromium.org> Reviewed-by: Christian König <christian.koenig(a)amd.com> Reviewed-by: Dmitry Osipenko <dmitry.osipenko(a)collabora.com> --- drivers/gpu/drm/drm_syncobj.c | 47 +++++++++++++++++++++++++++-------- include/uapi/drm/drm.h | 4 +++ 2 files changed, 41 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c index 4f2ab8a7b50f..636cd83ca29e 100644 --- a/drivers/gpu/drm/drm_syncobj.c +++ b/drivers/gpu/drm/drm_syncobj.c @@ -741,7 +741,7 @@ static int drm_syncobj_fd_to_handle(struct drm_file *file_private, } static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private, - int fd, int handle) + int fd, int handle, u64 point) { struct dma_fence *fence = sync_file_get_fence(fd); struct drm_syncobj *syncobj; @@ -755,14 +755,24 @@ static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private, return -ENOENT; } - drm_syncobj_replace_fence(syncobj, fence); + if (point) { + struct dma_fence_chain *chain = dma_fence_chain_alloc(); + + if (!chain) + return -ENOMEM; + + drm_syncobj_add_point(syncobj, chain, fence, point); + } else { + drm_syncobj_replace_fence(syncobj, fence); + } + dma_fence_put(fence); drm_syncobj_put(syncobj); return 0; } static int drm_syncobj_export_sync_file(struct drm_file *file_private, - int handle, int *p_fd) + int handle, u64 point, int *p_fd) { int ret; struct dma_fence *fence; @@ -772,7 +782,7 @@ static int drm_syncobj_export_sync_file(struct drm_file *file_private, if (fd < 0) return fd; - ret = drm_syncobj_find_fence(file_private, handle, 0, 0, &fence); + ret = drm_syncobj_find_fence(file_private, handle, point, 0, &fence); if (ret) goto err_put_fd; @@ -869,6 +879,9 @@ drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data, struct drm_file *file_private) { struct drm_syncobj_handle *args = data; + unsigned int valid_flags = DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE | + DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE; + u64 point = 0; if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ)) return -EOPNOTSUPP; @@ -876,13 +889,18 @@ drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data, if (args->pad) return -EINVAL; - if (args->flags != 0 && - args->flags != DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE) + if (args->flags & ~valid_flags) return -EINVAL; + if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE) + point = args->point; + if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE) return drm_syncobj_export_sync_file(file_private, args->handle, - &args->fd); + point, &args->fd); + + if (args->point) + return -EINVAL; return drm_syncobj_handle_to_fd(file_private, args->handle, &args->fd); @@ -893,6 +911,9 @@ drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data, struct drm_file *file_private) { struct drm_syncobj_handle *args = data; + unsigned int valid_flags = DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE | + DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE; + u64 point = 0; if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ)) return -EOPNOTSUPP; @@ -900,14 +921,20 @@ drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data, if (args->pad) return -EINVAL; - if (args->flags != 0 && - args->flags != DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE) + if (args->flags & ~valid_flags) return -EINVAL; + if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE) + point = args->point; + if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE) return drm_syncobj_import_sync_file_fence(file_private, args->fd, - args->handle); + args->handle, + point); + + if (args->point) + return -EINVAL; return drm_syncobj_fd_to_handle(file_private, args->fd, &args->handle); diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h index 7fba37b94401..e63a71d3c607 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -905,13 +905,17 @@ struct drm_syncobj_destroy { }; #define DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE (1 << 0) +#define DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE (1 << 1) #define DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE (1 << 0) +#define DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE (1 << 1) struct drm_syncobj_handle { __u32 handle; __u32 flags; __s32 fd; __u32 pad; + + __u64 point; }; struct drm_syncobj_transfer { -- 2.49.0

1 day, 2 hours

[PATCH v7] drm/syncobj: Extend EXPORT_SYNC_FILE for timeline syncobjs

by Rob Clark

From: Rob Clark <robdclark(a)chromium.org> Add support for exporting a dma_fence fd for a specific point on a timeline. This is needed for vtest/vpipe[1][2] to implement timeline syncobj support, as it needs a way to turn a point on a timeline back into a dma_fence fd. It also closes an odd omission from the syncobj UAPI. [1] https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33433 [2] https://gitlab.freedesktop.org/virgl/virglrenderer/-/merge_requests/805 v2: Add DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE v3: Add unstaged uabi header hunk v4: Also handle IMPORT_SYNC_FILE case v5: Address comments from Dmitry v6: checkpatch.pl nits v7: Add check for DRIVER_SYNCOBJ_TIMELINE Signed-off-by: Rob Clark <robdclark(a)chromium.org> Reviewed-by: Christian König <christian.koenig(a)amd.com> Reviewed-by: Dmitry Osipenko <dmitry.osipenko(a)collabora.com> --- drivers/gpu/drm/drm_syncobj.c | 53 ++++++++++++++++++++++++++++------- include/uapi/drm/drm.h | 4 +++ 2 files changed, 47 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c index 4f2ab8a7b50f..3e41461eb9d6 100644 --- a/drivers/gpu/drm/drm_syncobj.c +++ b/drivers/gpu/drm/drm_syncobj.c @@ -741,7 +741,7 @@ static int drm_syncobj_fd_to_handle(struct drm_file *file_private, } static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private, - int fd, int handle) + int fd, int handle, u64 point) { struct dma_fence *fence = sync_file_get_fence(fd); struct drm_syncobj *syncobj; @@ -755,14 +755,24 @@ static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private, return -ENOENT; } - drm_syncobj_replace_fence(syncobj, fence); + if (point) { + struct dma_fence_chain *chain = dma_fence_chain_alloc(); + + if (!chain) + return -ENOMEM; + + drm_syncobj_add_point(syncobj, chain, fence, point); + } else { + drm_syncobj_replace_fence(syncobj, fence); + } + dma_fence_put(fence); drm_syncobj_put(syncobj); return 0; } static int drm_syncobj_export_sync_file(struct drm_file *file_private, - int handle, int *p_fd) + int handle, u64 point, int *p_fd) { int ret; struct dma_fence *fence; @@ -772,7 +782,7 @@ static int drm_syncobj_export_sync_file(struct drm_file *file_private, if (fd < 0) return fd; - ret = drm_syncobj_find_fence(file_private, handle, 0, 0, &fence); + ret = drm_syncobj_find_fence(file_private, handle, point, 0, &fence); if (ret) goto err_put_fd; @@ -869,6 +879,9 @@ drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data, struct drm_file *file_private) { struct drm_syncobj_handle *args = data; + unsigned int valid_flags = DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE | + DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE; + u64 point = 0; if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ)) return -EOPNOTSUPP; @@ -876,13 +889,21 @@ drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data, if (args->pad) return -EINVAL; - if (args->flags != 0 && - args->flags != DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE) + if (args->flags & ~valid_flags) return -EINVAL; + if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE) { + if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE)) + return -EOPNOTSUPP; + point = args->point; + } + if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE) return drm_syncobj_export_sync_file(file_private, args->handle, - &args->fd); + point, &args->fd); + + if (args->point) + return -EINVAL; return drm_syncobj_handle_to_fd(file_private, args->handle, &args->fd); @@ -893,6 +914,9 @@ drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data, struct drm_file *file_private) { struct drm_syncobj_handle *args = data; + unsigned int valid_flags = DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE | + DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE; + u64 point = 0; if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ)) return -EOPNOTSUPP; @@ -900,14 +924,23 @@ drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data, if (args->pad) return -EINVAL; - if (args->flags != 0 && - args->flags != DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE) + if (args->flags & ~valid_flags) return -EINVAL; + if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE) { + if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE)) + return -EOPNOTSUPP; + point = args->point; + } + if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE) return drm_syncobj_import_sync_file_fence(file_private, args->fd, - args->handle); + args->handle, + point); + + if (args->point) + return -EINVAL; return drm_syncobj_fd_to_handle(file_private, args->fd, &args->handle); diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h index 7fba37b94401..e63a71d3c607 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -905,13 +905,17 @@ struct drm_syncobj_destroy { }; #define DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE (1 << 0) +#define DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE (1 << 1) #define DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE (1 << 0) +#define DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE (1 << 1) struct drm_syncobj_handle { __u32 handle; __u32 flags; __s32 fd; __u32 pad; + + __u64 point; }; struct drm_syncobj_transfer { -- 2.49.0

1 day, 20 hours

[PATCH v5] drm/syncobj: Extend EXPORT_SYNC_FILE for timeline syncobjs

by Rob Clark

From: Rob Clark <robdclark(a)chromium.org> Add support for exporting a dma_fence fd for a specific point on a timeline. This is needed for vtest/vpipe[1][2] to implement timeline syncobj support, as it needs a way to turn a point on a timeline back into a dma_fence fd. It also closes an odd omission from the syncobj UAPI. [1] https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33433 [2] https://gitlab.freedesktop.org/virgl/virglrenderer/-/merge_requests/805 v2: Add DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE v3: Add unstaged uabi header hunk v4: Also handle IMPORT_SYNC_FILE case v5: Address comments from Dmitry Signed-off-by: Rob Clark <robdclark(a)chromium.org> --- drivers/gpu/drm/drm_syncobj.c | 45 +++++++++++++++++++++++++++-------- include/uapi/drm/drm.h | 4 ++++ 2 files changed, 39 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c index 4f2ab8a7b50f..b0a4c58fe726 100644 --- a/drivers/gpu/drm/drm_syncobj.c +++ b/drivers/gpu/drm/drm_syncobj.c @@ -741,7 +741,7 @@ static int drm_syncobj_fd_to_handle(struct drm_file *file_private, } static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private, - int fd, int handle) + int fd, int handle, u64 point) { struct dma_fence *fence = sync_file_get_fence(fd); struct drm_syncobj *syncobj; @@ -755,14 +755,22 @@ static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private, return -ENOENT; } - drm_syncobj_replace_fence(syncobj, fence); + if (point) { + struct dma_fence_chain *chain = dma_fence_chain_alloc(); + if (!chain) + return -ENOMEM; + drm_syncobj_add_point(syncobj, chain, fence, point); + } else { + drm_syncobj_replace_fence(syncobj, fence); + } + dma_fence_put(fence); drm_syncobj_put(syncobj); return 0; } static int drm_syncobj_export_sync_file(struct drm_file *file_private, - int handle, int *p_fd) + int handle, u64 point, int *p_fd) { int ret; struct dma_fence *fence; @@ -772,7 +780,7 @@ static int drm_syncobj_export_sync_file(struct drm_file *file_private, if (fd < 0) return fd; - ret = drm_syncobj_find_fence(file_private, handle, 0, 0, &fence); + ret = drm_syncobj_find_fence(file_private, handle, point, 0, &fence); if (ret) goto err_put_fd; @@ -869,6 +877,9 @@ drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data, struct drm_file *file_private) { struct drm_syncobj_handle *args = data; + unsigned valid_flags = DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE | + DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE; + u64 point = 0; if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ)) return -EOPNOTSUPP; @@ -876,13 +887,18 @@ drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data, if (args->pad) return -EINVAL; - if (args->flags != 0 && - args->flags != DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE) + if (args->flags & ~valid_flags) return -EINVAL; + if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE) + point = args->point; + if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE) return drm_syncobj_export_sync_file(file_private, args->handle, - &args->fd); + point, &args->fd); + + if (args->point) + return -EINVAL; return drm_syncobj_handle_to_fd(file_private, args->handle, &args->fd); @@ -893,6 +909,9 @@ drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data, struct drm_file *file_private) { struct drm_syncobj_handle *args = data; + unsigned valid_flags = DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE | + DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE; + u64 point = 0; if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ)) return -EOPNOTSUPP; @@ -900,14 +919,20 @@ drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data, if (args->pad) return -EINVAL; - if (args->flags != 0 && - args->flags != DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE) + if (args->flags & ~valid_flags) return -EINVAL; + if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE) + point = args->point; + if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE) return drm_syncobj_import_sync_file_fence(file_private, args->fd, - args->handle); + args->handle, + point); + + if (args->point) + return -EINVAL; return drm_syncobj_fd_to_handle(file_private, args->fd, &args->handle); diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h index 7fba37b94401..e63a71d3c607 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -905,13 +905,17 @@ struct drm_syncobj_destroy { }; #define DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE (1 << 0) +#define DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE (1 << 1) #define DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE (1 << 0) +#define DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE (1 << 1) struct drm_syncobj_handle { __u32 handle; __u32 flags; __s32 fd; __u32 pad; + + __u64 point; }; struct drm_syncobj_transfer { -- 2.49.0

2 days, 2 hours

Re: [PATCH v6 06/10] tee: new ioctl to a register tee_shm from a dmabuf file descriptor

by Jens Wiklander

On Tue, Apr 1, 2025 at 10:46 AM Sumit Garg <sumit.garg(a)kernel.org> wrote: > > On Tue, Mar 25, 2025 at 12:17:20PM +0100, Jens Wiklander wrote: > > Hi Sumit, > > > > On Tue, Mar 25, 2025 at 7:50 AM Sumit Garg <sumit.garg(a)kernel.org> wrote: > > > > > > Hi Jens, > > > > > > On Wed, Mar 05, 2025 at 02:04:12PM +0100, Jens Wiklander wrote: > > > > From: Etienne Carriere <etienne.carriere(a)linaro.org> > > > > > > > > Enable userspace to create a tee_shm object that refers to a dmabuf > > > > reference. > > > > > > > > Userspace registers the dmabuf file descriptor as in a tee_shm object. > > > > The registration is completed with a tee_shm file descriptor returned to > > > > userspace. > > > > > > > > Userspace is free to close the dmabuf file descriptor now since all the > > > > resources are now held via the tee_shm object. > > > > > > > > Closing the tee_shm file descriptor will release all resources used by the > > > > tee_shm object. > > > > > > > > This change only support dmabuf references that relates to physically > > > > contiguous memory buffers. > > Let's try to reframe this commit message to say that new ioctl allows to > register DMA buffers allocated from restricted/protected heaps with TEE > subsystem. > > > > > > > > > New tee_shm flag to identify tee_shm objects built from a registered > > > > dmabuf, TEE_SHM_DMA_BUF. > > > > > > > > Signed-off-by: Etienne Carriere <etienne.carriere(a)linaro.org> > > > > Signed-off-by: Olivier Masse <olivier.masse(a)nxp.com> > > > > Signed-off-by: Jens Wiklander <jens.wiklander(a)linaro.org> > > > > --- > > > > drivers/tee/tee_core.c | 145 ++++++++++++++++++++++++++----------- > > > > drivers/tee/tee_private.h | 1 + > > > > drivers/tee/tee_shm.c | 146 ++++++++++++++++++++++++++++++++++++-- > > > > include/linux/tee_core.h | 1 + > > > > include/linux/tee_drv.h | 10 +++ > > > > include/uapi/linux/tee.h | 29 ++++++++ > > > > 6 files changed, 288 insertions(+), 44 deletions(-) > > > > > > > > > > I am still trying to find if we really need a separate IOCTL to register > > > DMA heap with TEE subsystem. Can't we initialize tee_shm as a member of > > > struct tee_heap_buffer in tee_dma_heap_alloc() where the allocation > > > happens? > > > > No, that's not possible since we don't have a tee_context availble so > > we can't assign an ID that userspace can use for this shm object. > > > > We could add new attribute types TEE_IOCTL_PARAM_ATTR_TYPE_MEMFD_*, > > but it's a bit more complicated than that since we'd also need to > > update for the life cycle. > > Okay, that's fair enough. Lets take this new IOCTL approach then. > > > > > > > > We can always find a reference back to tee_shm object from DMA > > > buffer. > > > > Yes > > > > Cheers, > > Jens > > > > > > > > -Sumit > > > > > > > diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c > > > > index 685afcaa3ea1..3a71643766d5 100644 > > > > --- a/drivers/tee/tee_core.c > > > > +++ b/drivers/tee/tee_core.c > > > > @@ -353,6 +353,103 @@ tee_ioctl_shm_register(struct tee_context *ctx, > > > > return ret; > > > > } > > > > > > > > +static int > > > > +tee_ioctl_shm_register_fd(struct tee_context *ctx, > > > > + struct tee_ioctl_shm_register_fd_data __user *udata) > > > > +{ > > > > + struct tee_ioctl_shm_register_fd_data data; > > > > + struct tee_shm *shm; > > > > + long ret; > > > > + > > > > + if (copy_from_user(&data, udata, sizeof(data))) > > > > + return -EFAULT; > > > > + > > > > + /* Currently no input flags are supported */ > > > > + if (data.flags) > > > > + return -EINVAL; > > > > + > > > > + shm = tee_shm_register_fd(ctx, data.fd); > > > > + if (IS_ERR(shm)) > > > > + return -EINVAL; > > > > + > > > > + data.id = shm->id; > > > > + data.flags = shm->flags; > > > > + data.size = shm->size; > > > > + > > > > + if (copy_to_user(udata, &data, sizeof(data))) > > > > + ret = -EFAULT; > > > > + else > > > > + ret = tee_shm_get_fd(shm); > > > > + > > > > + /* > > > > + * When user space closes the file descriptor the shared memory > > > > + * should be freed or if tee_shm_get_fd() failed then it will > > > > + * be freed immediately. > > > > + */ > > > > + tee_shm_put(shm); > > > > + return ret; > > > > +} > > > > + > > > > +static int param_from_user_memref(struct tee_context *ctx, > > > > + struct tee_param_memref *memref, > > > > + struct tee_ioctl_param *ip) > > > > +{ > > > > + struct tee_shm *shm; > > > > + size_t offs = 0; > > > > + > > > > + /* > > > > + * If a NULL pointer is passed to a TA in the TEE, > > > > + * the ip.c IOCTL parameters is set to TEE_MEMREF_NULL > > > > + * indicating a NULL memory reference. > > > > + */ > > > > + if (ip->c != TEE_MEMREF_NULL) { > > > > + /* > > > > + * If we fail to get a pointer to a shared > > > > + * memory object (and increase the ref count) > > > > + * from an identifier we return an error. All > > > > + * pointers that has been added in params have > > > > + * an increased ref count. It's the callers > > > > + * responibility to do tee_shm_put() on all > > > > + * resolved pointers. > > > > + */ > > > > + shm = tee_shm_get_from_id(ctx, ip->c); > > > > + if (IS_ERR(shm)) > > > > + return PTR_ERR(shm); > > > > + > > > > + /* > > > > + * Ensure offset + size does not overflow > > > > + * offset and does not overflow the size of > > > > + * the referred shared memory object. > > > > + */ > > > > + if ((ip->a + ip->b) < ip->a || > > > > + (ip->a + ip->b) > shm->size) { > > > > + tee_shm_put(shm); > > > > + return -EINVAL; > > > > + } > > > > + > > > > + if (shm->flags & TEE_SHM_DMA_BUF) { > > This check is already done within tee_shm_get_parent_shm(), is it > redundant here? Yes, I'll remove it. > > > > > + struct tee_shm *parent_shm; > > > > + > > > > + parent_shm = tee_shm_get_parent_shm(shm, &offs); > > > > + if (parent_shm) { > > > > + tee_shm_put(shm); > > > > + shm = parent_shm; > > > > + } > > > > + } > > > > + } else if (ctx->cap_memref_null) { > > > > + /* Pass NULL pointer to OP-TEE */ > > > > + shm = NULL; > > > > + } else { > > > > + return -EINVAL; > > > > + } > > > > + > > > > + memref->shm_offs = ip->a + offs; > > > > + memref->size = ip->b; > > > > + memref->shm = shm; > > > > + > > > > + return 0; > > > > +} > > > > + > > > > static int params_from_user(struct tee_context *ctx, struct tee_param *params, > > > > size_t num_params, > > > > struct tee_ioctl_param __user *uparams) > > > > @@ -360,8 +457,8 @@ static int params_from_user(struct tee_context *ctx, struct tee_param *params, > > > > size_t n; > > > > > > > > for (n = 0; n < num_params; n++) { > > > > - struct tee_shm *shm; > > > > struct tee_ioctl_param ip; > > > > + int rc; > > > > > > > > if (copy_from_user(&ip, uparams + n, sizeof(ip))) > > > > return -EFAULT; > > > > @@ -384,45 +481,10 @@ static int params_from_user(struct tee_context *ctx, struct tee_param *params, > > > > case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT: > > > > case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT: > > > > case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT: > > > > - /* > > > > - * If a NULL pointer is passed to a TA in the TEE, > > > > - * the ip.c IOCTL parameters is set to TEE_MEMREF_NULL > > > > - * indicating a NULL memory reference. > > > > - */ > > > > - if (ip.c != TEE_MEMREF_NULL) { > > > > - /* > > > > - * If we fail to get a pointer to a shared > > > > - * memory object (and increase the ref count) > > > > - * from an identifier we return an error. All > > > > - * pointers that has been added in params have > > > > - * an increased ref count. It's the callers > > > > - * responibility to do tee_shm_put() on all > > > > - * resolved pointers. > > > > - */ > > > > - shm = tee_shm_get_from_id(ctx, ip.c); > > > > - if (IS_ERR(shm)) > > > > - return PTR_ERR(shm); > > > > - > > > > - /* > > > > - * Ensure offset + size does not overflow > > > > - * offset and does not overflow the size of > > > > - * the referred shared memory object. > > > > - */ > > > > - if ((ip.a + ip.b) < ip.a || > > > > - (ip.a + ip.b) > shm->size) { > > > > - tee_shm_put(shm); > > > > - return -EINVAL; > > > > - } > > > > - } else if (ctx->cap_memref_null) { > > > > - /* Pass NULL pointer to OP-TEE */ > > > > - shm = NULL; > > > > - } else { > > > > - return -EINVAL; > > > > - } > > > > - > > > > - params[n].u.memref.shm_offs = ip.a; > > > > - params[n].u.memref.size = ip.b; > > > > - params[n].u.memref.shm = shm; > > > > + rc = param_from_user_memref(ctx, &params[n].u.memref, > > > > + &ip); > > > > + if (rc) > > > > + return rc; > > This looks more of a refactoring, can we split it as a separate commit? Sure > > > > > break; > > > > default: > > > > /* Unknown attribute */ > > > > @@ -827,6 +889,8 @@ static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > > > > return tee_ioctl_shm_alloc(ctx, uarg); > > > > case TEE_IOC_SHM_REGISTER: > > > > return tee_ioctl_shm_register(ctx, uarg); > > > > + case TEE_IOC_SHM_REGISTER_FD: > > > > + return tee_ioctl_shm_register_fd(ctx, uarg); > > > > case TEE_IOC_OPEN_SESSION: > > > > return tee_ioctl_open_session(ctx, uarg); > > > > case TEE_IOC_INVOKE: > > > > @@ -1288,3 +1352,4 @@ MODULE_AUTHOR("Linaro"); > > > > MODULE_DESCRIPTION("TEE Driver"); > > > > MODULE_VERSION("1.0"); > > > > MODULE_LICENSE("GPL v2"); > > > > +MODULE_IMPORT_NS("DMA_BUF"); > > > > diff --git a/drivers/tee/tee_private.h b/drivers/tee/tee_private.h > > > > index 6c6ff5d5eed2..aad7f6c7e0f0 100644 > > > > --- a/drivers/tee/tee_private.h > > > > +++ b/drivers/tee/tee_private.h > > > > @@ -24,6 +24,7 @@ void teedev_ctx_put(struct tee_context *ctx); > > > > struct tee_shm *tee_shm_alloc_user_buf(struct tee_context *ctx, size_t size); > > > > struct tee_shm *tee_shm_register_user_buf(struct tee_context *ctx, > > > > unsigned long addr, size_t length); > > > > +struct tee_shm *tee_shm_get_parent_shm(struct tee_shm *shm, size_t *offs); > > > > > > > > int tee_heap_update_from_dma_buf(struct tee_device *teedev, > > > > struct dma_buf *dmabuf, size_t *offset, > > > > diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c > > > > index daf6e5cfd59a..8b79918468b5 100644 > > > > --- a/drivers/tee/tee_shm.c > > > > +++ b/drivers/tee/tee_shm.c > > > > @@ -4,6 +4,7 @@ > > > > */ > > > > #include <linux/anon_inodes.h> > > > > #include <linux/device.h> > > > > +#include <linux/dma-buf.h> > > > > #include <linux/idr.h> > > > > #include <linux/io.h> > > > > #include <linux/mm.h> > > > > @@ -15,6 +16,16 @@ > > > > #include <linux/highmem.h> > > > > #include "tee_private.h" > > > > > > > > +/* extra references appended to shm object for registered shared memory */ > > > > +struct tee_shm_dmabuf_ref { > > > > + struct tee_shm shm; > > > > + size_t offset; > > > > + struct dma_buf *dmabuf; > > > > + struct dma_buf_attachment *attach; > > > > + struct sg_table *sgt; > > > > + struct tee_shm *parent_shm; > > > > +}; > > > > + > > > > static void shm_put_kernel_pages(struct page **pages, size_t page_count) > > > > { > > > > size_t n; > > > > @@ -45,7 +56,23 @@ static void release_registered_pages(struct tee_shm *shm) > > > > > > > > static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm) > > > > { > > > > - if (shm->flags & TEE_SHM_POOL) { > > > > + struct tee_shm *parent_shm = NULL; > > > > + void *p = shm; > > > > + > > > > + if (shm->flags & TEE_SHM_DMA_BUF) { > > > > + struct tee_shm_dmabuf_ref *ref; > > > > + > > > > + ref = container_of(shm, struct tee_shm_dmabuf_ref, shm); > > > > + parent_shm = ref->parent_shm; > > > > + p = ref; > > > > + if (ref->attach) { > > > > + dma_buf_unmap_attachment(ref->attach, ref->sgt, > > > > + DMA_BIDIRECTIONAL); > > > > + > > > > + dma_buf_detach(ref->dmabuf, ref->attach); > > > > + } > > > > + dma_buf_put(ref->dmabuf); > > > > + } else if (shm->flags & TEE_SHM_POOL) { > > > > teedev->pool->ops->free(teedev->pool, shm); > > > > } else if (shm->flags & TEE_SHM_DYNAMIC) { > > > > int rc = teedev->desc->ops->shm_unregister(shm->ctx, shm); > > > > @@ -57,9 +84,10 @@ static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm) > > > > release_registered_pages(shm); > > > > } > > > > > > > > - teedev_ctx_put(shm->ctx); > > > > + if (shm->ctx) > > > > + teedev_ctx_put(shm->ctx); > > > > > > > > - kfree(shm); > > > > + kfree(p); > > > > > > > > tee_device_put(teedev); > > > > } > > > > @@ -169,7 +197,7 @@ struct tee_shm *tee_shm_alloc_user_buf(struct tee_context *ctx, size_t size) > > > > * tee_client_invoke_func(). The memory allocated is later freed with a > > > > * call to tee_shm_free(). > > > > * > > > > - * @returns a pointer to 'struct tee_shm' > > > > + * @returns a pointer to 'struct tee_shm' on success, and ERR_PTR on failure > > > > */ > > > > struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size) > > > > { > > > > @@ -179,6 +207,116 @@ struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size) > > > > } > > > > EXPORT_SYMBOL_GPL(tee_shm_alloc_kernel_buf); > > > > > > > > +struct tee_shm *tee_shm_register_fd(struct tee_context *ctx, int fd) > > > > +{ > > > > + struct tee_shm_dmabuf_ref *ref; > > > > + int rc; > > > > + > > > > + if (!tee_device_get(ctx->teedev)) > > > > + return ERR_PTR(-EINVAL); > > > > + > > > > + teedev_ctx_get(ctx); > > > > + > > > > + ref = kzalloc(sizeof(*ref), GFP_KERNEL); > > > > + if (!ref) { > > > > + rc = -ENOMEM; > > > > + goto err_put_tee; > > > > + } > > > > + > > > > + refcount_set(&ref->shm.refcount, 1); > > > > + ref->shm.ctx = ctx; > > > > + ref->shm.id = -1; > > > > + ref->shm.flags = TEE_SHM_DMA_BUF; > > > > + > > > > + ref->dmabuf = dma_buf_get(fd); > > > > + if (IS_ERR(ref->dmabuf)) { > > > > + rc = PTR_ERR(ref->dmabuf); > > > > + goto err_kfree_ref; > > > > + } > > > > + > > > > + rc = tee_heap_update_from_dma_buf(ctx->teedev, ref->dmabuf, > > > > + &ref->offset, &ref->shm, > > > > + &ref->parent_shm); > > > > + if (!rc) > > > > + goto out; > > > > + if (rc != -EINVAL) > > > > + goto err_put_dmabuf; > > > > + > > > > + ref->attach = dma_buf_attach(ref->dmabuf, &ctx->teedev->dev); > > > > + if (IS_ERR(ref->attach)) { > > > > + rc = PTR_ERR(ref->attach); > > > > + goto err_put_dmabuf; > > > > + } > > > > + > > > > + ref->sgt = dma_buf_map_attachment(ref->attach, DMA_BIDIRECTIONAL); > > > > + if (IS_ERR(ref->sgt)) { > > > > + rc = PTR_ERR(ref->sgt); > > > > + goto err_detach; > > > > + } > > > > + > > > > + if (sg_nents(ref->sgt->sgl) != 1) { > > > > + rc = PTR_ERR(ref->sgt->sgl); > > > > + goto err_unmap_attachement; > > > > + } > > > > + > > > > + ref->shm.paddr = page_to_phys(sg_page(ref->sgt->sgl)); > > > > + ref->shm.size = ref->sgt->sgl->length; > > > > + > > > > +out: > > > > + mutex_lock(&ref->shm.ctx->teedev->mutex); > > > > + ref->shm.id = idr_alloc(&ref->shm.ctx->teedev->idr, &ref->shm, > > > > + 1, 0, GFP_KERNEL); > > > > + mutex_unlock(&ref->shm.ctx->teedev->mutex); > > > > + if (ref->shm.id < 0) { > > > > + rc = ref->shm.id; > > > > + if (ref->attach) > > > > + goto err_unmap_attachement; > > > > + goto err_put_dmabuf; > > > > + } > > > > + > > > > + return &ref->shm; > > > > + > > > > +err_unmap_attachement: > > > > + dma_buf_unmap_attachment(ref->attach, ref->sgt, DMA_BIDIRECTIONAL); > > > > +err_detach: > > > > + dma_buf_detach(ref->dmabuf, ref->attach); > > > > +err_put_dmabuf: > > > > + dma_buf_put(ref->dmabuf); > > > > +err_kfree_ref: > > > > + kfree(ref); > > > > +err_put_tee: > > > > + teedev_ctx_put(ctx); > > > > + tee_device_put(ctx->teedev); > > > > + > > > > + return ERR_PTR(rc); > > > > +} > > > > +EXPORT_SYMBOL_GPL(tee_shm_register_fd); > > > > + > > > > +struct tee_shm *tee_shm_get_parent_shm(struct tee_shm *shm, size_t *offs) > > > > +{ > > > > + struct tee_shm *parent_shm = NULL; > > > > + > > > > + if (shm->flags & TEE_SHM_DMA_BUF) { > > > > + struct tee_shm_dmabuf_ref *ref; > > > > + > > > > + ref = container_of(shm, struct tee_shm_dmabuf_ref, shm); > > > > + if (ref->parent_shm) { > > > > + /* > > > > + * the shm already has one reference to > > > > + * ref->parent_shm so we should be clear of 0. > > > > + * We're getting another reference since the caller > > > > + * of this function expects to put the returned > > > > + * parent_shm when it's done with it. > > This seems a bit complicated, can we rather inline this API as I can't > see any other current user? OK Cheers, Jens > > -Sumit > > > > > + */ > > > > + parent_shm = ref->parent_shm; > > > > + refcount_inc(&parent_shm->refcount); > > > > + *offs = ref->offset; > > > > + } > > > > + } > > > > + > > > > + return parent_shm; > > > > +} > > > > + > > > > /** > > > > * tee_shm_alloc_priv_buf() - Allocate shared memory for a privately shared > > > > * kernel buffer > > > > diff --git a/include/linux/tee_core.h b/include/linux/tee_core.h > > > > index 16ef078247ae..6bd833b6d0e1 100644 > > > > --- a/include/linux/tee_core.h > > > > +++ b/include/linux/tee_core.h > > > > @@ -28,6 +28,7 @@ > > > > #define TEE_SHM_USER_MAPPED BIT(1) /* Memory mapped in user space */ > > > > #define TEE_SHM_POOL BIT(2) /* Memory allocated from pool */ > > > > #define TEE_SHM_PRIV BIT(3) /* Memory private to TEE driver */ > > > > +#define TEE_SHM_DMA_BUF BIT(4) /* Memory with dma-buf handle */ > > > > > > > > #define TEE_DEVICE_FLAG_REGISTERED 0x1 > > > > #define TEE_MAX_DEV_NAME_LEN 32 > > > > diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h > > > > index a54c203000ed..824f1251de60 100644 > > > > --- a/include/linux/tee_drv.h > > > > +++ b/include/linux/tee_drv.h > > > > @@ -116,6 +116,16 @@ struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size); > > > > struct tee_shm *tee_shm_register_kernel_buf(struct tee_context *ctx, > > > > void *addr, size_t length); > > > > > > > > +/** > > > > + * tee_shm_register_fd() - Register shared memory from file descriptor > > > > + * > > > > + * @ctx: Context that allocates the shared memory > > > > + * @fd: Shared memory file descriptor reference > > > > + * > > > > + * @returns a pointer to 'struct tee_shm' on success, and ERR_PTR on failure > > > > + */ > > > > +struct tee_shm *tee_shm_register_fd(struct tee_context *ctx, int fd); > > > > + > > > > /** > > > > * tee_shm_free() - Free shared memory > > > > * @shm: Handle to shared memory to free > > > > diff --git a/include/uapi/linux/tee.h b/include/uapi/linux/tee.h > > > > index d0430bee8292..1f9a4ac2b211 100644 > > > > --- a/include/uapi/linux/tee.h > > > > +++ b/include/uapi/linux/tee.h > > > > @@ -118,6 +118,35 @@ struct tee_ioctl_shm_alloc_data { > > > > #define TEE_IOC_SHM_ALLOC _IOWR(TEE_IOC_MAGIC, TEE_IOC_BASE + 1, \ > > > > struct tee_ioctl_shm_alloc_data) > > > > > > > > +/** > > > > + * struct tee_ioctl_shm_register_fd_data - Shared memory registering argument > > > > + * @fd: [in] File descriptor identifying the shared memory > > > > + * @size: [out] Size of shared memory to allocate > > > > + * @flags: [in] Flags to/from allocation. > > > > + * @id: [out] Identifier of the shared memory > > > > + * > > > > + * The flags field should currently be zero as input. Updated by the call > > > > + * with actual flags as defined by TEE_IOCTL_SHM_* above. > > > > + * This structure is used as argument for TEE_IOC_SHM_REGISTER_FD below. > > > > + */ > > > > +struct tee_ioctl_shm_register_fd_data { > > > > + __s64 fd; > > > > + __u64 size; > > > > + __u32 flags; > > > > + __s32 id; > > > > +}; > > > > + > > > > +/** > > > > + * TEE_IOC_SHM_REGISTER_FD - register a shared memory from a file descriptor > > > > + * > > > > + * Returns a file descriptor on success or < 0 on failure > > > > + * > > > > + * The returned file descriptor refers to the shared memory object in kernel > > > > + * land. The shared memory is freed when the descriptor is closed. > > > > + */ > > > > +#define TEE_IOC_SHM_REGISTER_FD _IOWR(TEE_IOC_MAGIC, TEE_IOC_BASE + 8, \ > > > > + struct tee_ioctl_shm_register_fd_data) > > > > + > > > > /** > > > > * struct tee_ioctl_buf_data - Variable sized buffer > > > > * @buf_ptr: [in] A __user pointer to a buffer > > > > -- > > > > 2.43.0 > > > >

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Linaro-mm-sig April 2025