USB: dwc3: remove debugfs root dentry storage

There is no need to keep around the debugfs "root" directory for the
dwc3 device.  Instead, look it up anytime we need to find it.  This will
help when callers get out-of-order and we had the potential to have a
"stale" pointer around for the root dentry, as has happened in the past.

Tested-by: Jack Pham <jackp@codeaurora.org>
Reviewed-by: Peter Chen <peter.chen@kernel.org>
Acked-by: Felipe Balbi <balbi@kernel.org>
Link: https://lore.kernel.org/r/20210609093924.3293230-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index c5d5760cdf53e63fdcbb6bed12b2cfccab084e01..dccdf13b5f9e2b7f37badcfc8aeff60346d87f53 100644 (file)
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -1013,7 +1013,6 @@ struct dwc3_scratchpad_array {
  * @link_state: link state
  * @speed: device speed (super, high, full, low)
  * @hwparams: copy of hwparams registers
- * @root: debugfs root folder pointer
  * @regset: debugfs pointer to regdump file
  * @dbg_lsp_select: current debug lsp mux register selection
  * @test_mode: true when we're entering a USB test mode
@@ -1222,7 +1221,6 @@ struct dwc3 {
        u8                      num_eps;
 
        struct dwc3_hwparams    hwparams;
-       struct dentry           *root;
        struct debugfs_regset32 *regset;
 
        u32                     dbg_lsp_select;

diff --git a/drivers/usb/dwc3/debugfs.c b/drivers/usb/dwc3/debugfs.c
index 5dbbe53269d391c58eaed4f09dd6f41cd4b6394f..f2b7675c7f6212cfa9ba90a4262d16f375f3a2a9 100644 (file)
--- a/drivers/usb/dwc3/debugfs.c
+++ b/drivers/usb/dwc3/debugfs.c
@@ -889,8 +889,10 @@ static void dwc3_debugfs_create_endpoint_files(struct dwc3_ep *dep,
 void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep)
 {
        struct dentry           *dir;
+       struct dentry           *root;
 
-       dir = debugfs_create_dir(dep->name, dep->dwc->root);
+       root = debugfs_lookup(dev_name(dep->dwc->dev), usb_debug_root);
+       dir = debugfs_create_dir(dep->name, root);
        dwc3_debugfs_create_endpoint_files(dep, dir);
 }
 
@@ -909,8 +911,6 @@ void dwc3_debugfs_init(struct dwc3 *dwc)
        dwc->regset->base = dwc->regs - DWC3_GLOBALS_REGS_START;
 
        root = debugfs_create_dir(dev_name(dwc->dev), usb_debug_root);
-       dwc->root = root;
-
        debugfs_create_regset32("regdump", 0444, root, dwc->regset);
        debugfs_create_file("lsp_dump", 0644, root, dwc, &dwc3_lsp_fops);
 
@@ -929,6 +929,6 @@ void dwc3_debugfs_init(struct dwc3 *dwc)
 
 void dwc3_debugfs_exit(struct dwc3 *dwc)
 {
-       debugfs_remove_recursive(dwc->root);
+       debugfs_remove(debugfs_lookup(dev_name(dwc->dev), usb_debug_root));
        kfree(dwc->regset);
 }

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 7cc99b6d0bfe815eb74bd08e1c2d9b2ef8a1b2c2..026a2ad0fc80fffa41d86a4699ed819042e049e0 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2799,7 +2799,9 @@ static void dwc3_gadget_free_endpoints(struct dwc3 *dwc)
                        list_del(&dep->endpoint.ep_list);
                }
 
-               debugfs_remove_recursive(debugfs_lookup(dep->name, dwc->root));
+               debugfs_remove_recursive(debugfs_lookup(dep->name,
+                               debugfs_lookup(dev_name(dep->dwc->dev),
+                                              usb_debug_root)));
                kfree(dep);
        }
 }