On 5/5/25 00:41, T.J. Mercier wrote:
Expose the debugfs list and mutex so they are usable for the creation of a BPF iterator for dmabufs without the need for CONFIG_DEBUG_FS. Rename the symbols so it's clear debugfs is not required, and that the list contains dmabufs and not some other type.
Signed-off-by: T.J. Mercier tjmercier@google.com
Reviewed-by: Christian König christian.koenig@amd.com
v2: Make the DMA buffer list independent of CONFIG_DEBUG_FS per Christian König drivers/dma-buf/dma-buf.c | 40 +++++++++++++++------------------------ include/linux/dma-buf.h | 6 ++++-- 2 files changed, 19 insertions(+), 27 deletions(-)
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 5baa83b85515..7260bdd77c75 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -35,35 +35,25 @@ static inline int is_dma_buf_file(struct file *); -#if IS_ENABLED(CONFIG_DEBUG_FS) -static DEFINE_MUTEX(debugfs_list_mutex); -static LIST_HEAD(debugfs_list); +DEFINE_MUTEX(dmabuf_list_mutex); +LIST_HEAD(dmabuf_list); -static void __dma_buf_debugfs_list_add(struct dma_buf *dmabuf) +static void __dma_buf_list_add(struct dma_buf *dmabuf) {
- mutex_lock(&debugfs_list_mutex);
- list_add(&dmabuf->list_node, &debugfs_list);
- mutex_unlock(&debugfs_list_mutex);
- mutex_lock(&dmabuf_list_mutex);
- list_add(&dmabuf->list_node, &dmabuf_list);
- mutex_unlock(&dmabuf_list_mutex);
} -static void __dma_buf_debugfs_list_del(struct dma_buf *dmabuf) +static void __dma_buf_list_del(struct dma_buf *dmabuf) { if (!dmabuf) return;
- mutex_lock(&debugfs_list_mutex);
- mutex_lock(&dmabuf_list_mutex); list_del(&dmabuf->list_node);
- mutex_unlock(&debugfs_list_mutex);
- mutex_unlock(&dmabuf_list_mutex);
} -#else -static void __dma_buf_debugfs_list_add(struct dma_buf *dmabuf) -{ -}
-static void __dma_buf_debugfs_list_del(struct dma_buf *dmabuf) -{ -} -#endif static char *dmabuffs_dname(struct dentry *dentry, char *buffer, int buflen) { @@ -115,7 +105,7 @@ static int dma_buf_file_release(struct inode *inode, struct file *file) if (!is_dma_buf_file(file)) return -EINVAL;
- __dma_buf_debugfs_list_del(file->private_data);
- __dma_buf_list_del(file->private_data);
return 0; } @@ -689,7 +679,7 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info) file->f_path.dentry->d_fsdata = dmabuf; dmabuf->file = file;
- __dma_buf_debugfs_list_add(dmabuf);
- __dma_buf_list_add(dmabuf);
return dmabuf; @@ -1630,7 +1620,7 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused) size_t size = 0; int ret;
- ret = mutex_lock_interruptible(&debugfs_list_mutex);
- ret = mutex_lock_interruptible(&dmabuf_list_mutex);
if (ret) return ret; @@ -1639,7 +1629,7 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused) seq_printf(s, "%-8s\t%-8s\t%-8s\t%-8s\texp_name\t%-8s\tname\n", "size", "flags", "mode", "count", "ino");
- list_for_each_entry(buf_obj, &debugfs_list, list_node) {
- list_for_each_entry(buf_obj, &dmabuf_list, list_node) {
ret = dma_resv_lock_interruptible(buf_obj->resv, NULL); if (ret) @@ -1676,11 +1666,11 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused) seq_printf(s, "\nTotal %d objects, %zu bytes\n", count, size);
- mutex_unlock(&debugfs_list_mutex);
- mutex_unlock(&dmabuf_list_mutex); return 0;
error_unlock:
- mutex_unlock(&debugfs_list_mutex);
- mutex_unlock(&dmabuf_list_mutex); return ret;
} diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 36216d28d8bd..ebcd208272bf 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -18,6 +18,7 @@ #include <linux/err.h> #include <linux/scatterlist.h> #include <linux/list.h> +#include <linux/mutex.h> #include <linux/dma-mapping.h> #include <linux/fs.h> #include <linux/dma-fence.h> @@ -370,10 +371,8 @@ struct dma_buf { */ struct module *owner; -#if IS_ENABLED(CONFIG_DEBUG_FS) /** @list_node: node for dma_buf accounting and debugging. */ struct list_head list_node; -#endif /** @priv: exporter specific private data for this buffer object. */ void *priv; @@ -556,6 +555,9 @@ struct dma_buf_export_info { struct dma_buf_export_info name = { .exp_name = KBUILD_MODNAME, \ .owner = THIS_MODULE } +extern struct list_head dmabuf_list; +extern struct mutex dmabuf_list_mutex;
/**
- get_dma_buf - convenience wrapper for get_file.
- @dmabuf: [in] pointer to dma_buf