Both debugfs_create_dir() and debugfs_create_file() return ERR_PTR
and never return NULL.
As Hans suggested, this patch removes the error checking for both
debugfs_create_dir() and debugfs_create_file() in smsdvb_debugfs_create().
This is because the DebugFS kernel API is developed in a way that the
caller can safely ignore the errors that occur during the creation of
DebugFS nodes. The debugfs APIs have a IS_ERR() judge in start_creating()
which can handle it gracefully. So these checks are unnecessary.
And as Hans pointed out, it's much better to first allocate debug_data
before calling debugfs_create_dir, which need not to clean anything up in
that case.
Fixes: 503efe5cfc9f ("[media] siano: split debugfs code into a separate file")
Signed-off-by: Jinjie Ruan <ruanjinjie@xxxxxxxxxx>
Suggested-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
---
v2:
- Remove the err check instead of using IS_ERR to replace NULL check.
- Allocate debug_data before calling debugfs_create_dir().
- Update the commit message and title.
- Add suggested-by.
---
drivers/media/common/siano/smsdvb-debugfs.c | 22 ++++++---------------
1 file changed, 6 insertions(+), 16 deletions(-)
diff --git a/drivers/media/common/siano/smsdvb-debugfs.c b/drivers/media/common/siano/smsdvb-debugfs.c
index e0beefd80d7b..73990e469df9 100644
--- a/drivers/media/common/siano/smsdvb-debugfs.c
+++ b/drivers/media/common/siano/smsdvb-debugfs.c
@@ -353,31 +353,21 @@ static const struct file_operations debugfs_stats_ops = {
int smsdvb_debugfs_create(struct smsdvb_client_t *client)
{
struct smscore_device_t *coredev = client->coredev;
- struct dentry *d;
struct smsdvb_debugfs *debug_data;
if (!smsdvb_debugfs_usb_root || !coredev->is_usb_device)
return -ENODEV;
- client->debugfs = debugfs_create_dir(coredev->devpath,
- smsdvb_debugfs_usb_root);
- if (IS_ERR_OR_NULL(client->debugfs)) {
- pr_info("Unable to create debugfs %s directory.\n",
- coredev->devpath);
- return -ENODEV;
- }
-
- d = debugfs_create_file("stats", S_IRUGO | S_IWUSR, client->debugfs,
- client, &debugfs_stats_ops);
- if (!d) {
- debugfs_remove(client->debugfs);
- return -ENOMEM;
- }
-
debug_data = kzalloc(sizeof(*client->debug_data), GFP_KERNEL);
if (!debug_data)
return -ENOMEM;
+ client->debugfs = debugfs_create_dir(coredev->devpath,
+ smsdvb_debugfs_usb_root);
+
+ debugfs_create_file("stats", S_IRUGO | S_IWUSR, client->debugfs,
+ client, &debugfs_stats_ops);
+
client->debug_data = debug_data;
client->prt_dvb_stats = smsdvb_print_dvb_stats;
client->prt_isdb_stats = smsdvb_print_isdb_stats;
--
2.34.1
