On 8/7/26 17:54, Thierry Reding wrote: > From: Thierry Reding <[email protected]> > > Add a callback to struct dma_heap_ops that heap providers can implement > to show information about the state of the heap in debugfs. A top-level > directory named "dma_heap" is created in debugfs and individual files > will be named after the heaps. > > Reviewed-by: Maxime Ripard <[email protected]> > Signed-off-by: Thierry Reding <[email protected]>
Reviewed-by: Christian König <[email protected]> > --- > drivers/dma-buf/dma-heap.c | 56 > ++++++++++++++++++++++++++++++++++++++++++++++ > include/linux/dma-heap.h | 2 ++ > 2 files changed, 58 insertions(+) > > diff --git a/drivers/dma-buf/dma-heap.c b/drivers/dma-buf/dma-heap.c > index 3937dd41bb0f..389cddd07c8d 100644 > --- a/drivers/dma-buf/dma-heap.c > +++ b/drivers/dma-buf/dma-heap.c > @@ -7,6 +7,7 @@ > */ > > #include <linux/cdev.h> > +#include <linux/debugfs.h> > #include <linux/device.h> > #include <linux/dma-buf.h> > #include <linux/dma-heap.h> > @@ -225,6 +226,46 @@ const char *dma_heap_get_name(struct dma_heap *heap) > } > EXPORT_SYMBOL_NS_GPL(dma_heap_get_name, "DMA_BUF_HEAP"); > > +#ifdef CONFIG_DEBUG_FS > +static int dma_heap_debug_show(struct seq_file *s, void *unused) > +{ > + struct dma_heap *heap = s->private; > + int err = 0; > + > + if (heap->ops && heap->ops->show) > + err = heap->ops->show(s, heap); > + > + return err; > +} > +DEFINE_SHOW_ATTRIBUTE(dma_heap_debug); > + > +static struct dentry *dma_heap_debugfs_dir; > + > +static void dma_heap_init_debugfs(void) > +{ > + struct dentry *dir; > + > + dir = debugfs_create_dir("dma_heap", NULL); > + if (IS_ERR(dir)) > + return; > + > + dma_heap_debugfs_dir = dir; > +} > + > +static void dma_heap_exit_debugfs(void) > +{ > + debugfs_remove_recursive(dma_heap_debugfs_dir); > +} > +#else > +static void dma_heap_init_debugfs(void) > +{ > +} > + > +static void dma_heap_exit_debugfs(void) > +{ > +} > +#endif > + > /** > * dma_heap_add - adds a heap to dmabuf heaps > * @exp_info: information needed to register this heap > @@ -299,6 +340,13 @@ struct dma_heap *dma_heap_add(const struct > dma_heap_export_info *exp_info) > > /* Add heap to the list */ > list_add(&heap->list, &heap_list); > + > +#ifdef CONFIG_DEBUG_FS > + if (heap->ops && heap->ops->show) > + debugfs_create_file(heap->name, 0444, dma_heap_debugfs_dir, > + heap, &dma_heap_debug_fops); > +#endif > + > mutex_unlock(&heap_list_lock); > > return heap; > @@ -335,6 +383,14 @@ static int dma_heap_init(void) > } > dma_heap_class->devnode = dma_heap_devnode; > > + dma_heap_init_debugfs(); > + > return 0; > } > subsys_initcall(dma_heap_init); > + > +static void __exit dma_heap_exit(void) > +{ > + dma_heap_exit_debugfs(); > +} > +__exitcall(dma_heap_exit); > diff --git a/include/linux/dma-heap.h b/include/linux/dma-heap.h > index 648328a64b27..1c9bed1f4dde 100644 > --- a/include/linux/dma-heap.h > +++ b/include/linux/dma-heap.h > @@ -12,6 +12,7 @@ > #include <linux/types.h> > > struct dma_heap; > +struct seq_file; > > /** > * struct dma_heap_ops - ops to operate on a given heap > @@ -24,6 +25,7 @@ struct dma_heap_ops { > unsigned long len, > u32 fd_flags, > u64 heap_flags); > + int (*show)(struct seq_file *s, struct dma_heap *heap); > }; > > /** >
