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.
Signed-off-by: Thierry Reding <[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 d230ddeb24e0..9784fa74ce53 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> @@ -223,6 +224,46 @@ 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 @@ -297,6 +338,13 @@ 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; @@ -333,6 +381,14 @@ 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); }; /** -- 2.52.0
