[PATCH v7 02/15] swiotlb: Refactor swiotlb_create_debugfs

Claire Chang
2021-05-18T06:42:54Z

Split the debugfs creation to make the code reusable for supporting
different bounce buffer pools, e.g. restricted DMA pool.

Signed-off-by: Claire Chang <tientzu@chromium.org>
---
kernel/dma/swiotlb.c | 25 +++++++++++++++++++------
1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index d3232fc19385..b849b01a446f 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -64,6 +64,7 @@
enum swiotlb_force swiotlb_force;

struct io_tlb_mem *io_tlb_default_mem;
+static struct dentry *debugfs_dir;

/*
* Max segment that we can provide which (if pages are contingous) will
@@ -662,18 +663,30 @@ EXPORT_SYMBOL_GPL(is_swiotlb_active);

#ifdef CONFIG_DEBUG_FS

-static int __init swiotlb_create_debugfs(void)
+static void swiotlb_create_debugfs(struct io_tlb_mem *mem, const char *name)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
-
if (!mem)
- return 0;
- mem->debugfs = debugfs_create_dir("swiotlb", NULL);
+ return;
+
+ mem->debugfs = debugfs_create_dir(name, debugfs_dir);
debugfs_create_ulong("io_tlb_nslabs", 0400, mem->debugfs, &mem->nslabs);
debugfs_create_ulong("io_tlb_used", 0400, mem->debugfs, &mem->used);
+}
+
+static int __init swiotlb_create_default_debugfs(void)
+{
+ struct io_tlb_mem *mem = io_tlb_default_mem;
+
+ if (mem) {
+ swiotlb_create_debugfs(mem, "swiotlb");
+ debugfs_dir = mem->debugfs;
+ } else {
+ debugfs_dir = debugfs_create_dir("swiotlb", NULL);
+ }
+
return 0;
}

-late_initcall(swiotlb_create_debugfs);
+late_initcall(swiotlb_create_default_debugfs);

#endif
--
2.31.1.751.gd2f1c929bd-goog