From 747bda7bb5b1644a06734900326847a5d353c448 Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann Date: Fri, 19 Apr 2024 10:29:00 +0200 Subject: fbdev/deferred-io: Provide get_page hook in struct fb_deferred_io Add a callback for drivers to provide framebuffer pages to fbdev's deferred-I/O helpers. Implementations need to acquire a reference on the page before returning it. Returning NULL generates a SIGBUS signal. This will be useful for DRM's fbdev emulation with GEM-shmem buffer objects. v2: - fix typo in commit message (Javier) Signed-off-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/20240419083331.7761-8-tzimmermann@suse.de --- include/linux/fb.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/fb.h b/include/linux/fb.h index 811e47f9d1c3..5358edbb9c0b 100644 --- a/include/linux/fb.h +++ b/include/linux/fb.h @@ -225,6 +225,7 @@ struct fb_deferred_io { struct mutex lock; /* mutex that protects the pageref list */ struct list_head pagereflist; /* list of pagerefs for touched pages */ /* callback */ + struct page *(*get_page)(struct fb_info *info, unsigned long offset); void (*deferred_io)(struct fb_info *info, struct list_head *pagelist); }; #endif -- cgit v1.2.3 From 983095eaf6c161ef73d96152bfc1a99ca051cd57 Mon Sep 17 00:00:00 2001 From: Christophe JAILLET Date: Sat, 25 May 2024 18:00:31 +0200 Subject: dma-buf/fence-array: Add flex array to struct dma_fence_array MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This is an effort to get rid of all multiplications from allocation functions in order to prevent integer overflows [1][2]. The "struct dma_fence_array" can be refactored to add a flex array in order to have the "callback structures allocated behind the array" be more explicit. Do so: - makes the code more readable and safer. - allows using __counted_by() for additional checks - avoids some pointer arithmetic in dma_fence_array_enable_signaling() Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] Link: https://github.com/KSPP/linux/issues/160 [2] Signed-off-by: Christophe JAILLET Reviewed-by: Kees Cook Reviewed-by: Christian König Link: https://patchwork.freedesktop.org/patch/msgid/8b4e556e07b5dd78bb8a39b67ea0a43b199083c8.1716652811.git.christophe.jaillet@wanadoo.fr Signed-off-by: Christian König --- drivers/dma-buf/dma-fence-array.c | 10 ++++------ include/linux/dma-fence-array.h | 3 +++ 2 files changed, 7 insertions(+), 6 deletions(-) (limited to 'include/linux') diff --git a/drivers/dma-buf/dma-fence-array.c b/drivers/dma-buf/dma-fence-array.c index 9b3ce8948351..c74ac197d5fe 100644 --- a/drivers/dma-buf/dma-fence-array.c +++ b/drivers/dma-buf/dma-fence-array.c @@ -70,7 +70,7 @@ static void dma_fence_array_cb_func(struct dma_fence *f, static bool dma_fence_array_enable_signaling(struct dma_fence *fence) { struct dma_fence_array *array = to_dma_fence_array(fence); - struct dma_fence_array_cb *cb = (void *)(&array[1]); + struct dma_fence_array_cb *cb = array->callbacks; unsigned i; for (i = 0; i < array->num_fences; ++i) { @@ -168,22 +168,20 @@ struct dma_fence_array *dma_fence_array_create(int num_fences, bool signal_on_any) { struct dma_fence_array *array; - size_t size = sizeof(*array); WARN_ON(!num_fences || !fences); - /* Allocate the callback structures behind the array. */ - size += num_fences * sizeof(struct dma_fence_array_cb); - array = kzalloc(size, GFP_KERNEL); + array = kzalloc(struct_size(array, callbacks, num_fences), GFP_KERNEL); if (!array) return NULL; + array->num_fences = num_fences; + spin_lock_init(&array->lock); dma_fence_init(&array->base, &dma_fence_array_ops, &array->lock, context, seqno); init_irq_work(&array->work, irq_dma_fence_array_work); - array->num_fences = num_fences; atomic_set(&array->num_pending, signal_on_any ? 1 : num_fences); array->fences = fences; diff --git a/include/linux/dma-fence-array.h b/include/linux/dma-fence-array.h index ec7f25def392..29c5650c1038 100644 --- a/include/linux/dma-fence-array.h +++ b/include/linux/dma-fence-array.h @@ -33,6 +33,7 @@ struct dma_fence_array_cb { * @num_pending: fences in the array still pending * @fences: array of the fences * @work: internal irq_work function + * @callbacks: array of callback helpers */ struct dma_fence_array { struct dma_fence base; @@ -43,6 +44,8 @@ struct dma_fence_array { struct dma_fence **fences; struct irq_work work; + + struct dma_fence_array_cb callbacks[] __counted_by(num_fences); }; /** -- cgit v1.2.3