[1/2] blktrace: don't centralize grabbing q->debugfs_mutex in blk_trace_ioctl

Commit Message

Ming Lei Nov. 28, 2024, 12:50 p.m. UTC

Call each handler directly and the handler do grab q->debugfs_mutex,
prepare for killing dependency between ->debug_mutex and ->mmap_lock.

Signed-off-by: Ming Lei <[e-mail]>
---
 kernel/trace/blktrace.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

Patch

diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 8fd292d34d89..f01aae3a2f7b 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -732,34 +732,32 @@  int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg)
 	int ret, start = 0;
 	char b[BDEVNAME_SIZE];
 
-	mutex_lock(&q->debugfs_mutex);
-
 	switch (cmd) {
 	case BLKTRACESETUP:
 		snprintf(b, sizeof(b), "%pg", bdev);
-		ret = __blk_trace_setup(q, b, bdev->bd_dev, bdev, arg);
+		ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg);
 		break;
 #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64)
 	case BLKTRACESETUP32:
 		snprintf(b, sizeof(b), "%pg", bdev);
+		mutex_lock(&q->debugfs_mutex);
 		ret = compat_blk_trace_setup(q, b, bdev->bd_dev, bdev, arg);
+		mutex_unlock(&q->debugfs_mutex);
 		break;
 #endif
 	case BLKTRACESTART:
 		start = 1;
 		fallthrough;
 	case BLKTRACESTOP:
-		ret = __blk_trace_startstop(q, start);
+		ret = blk_trace_startstop(q, start);
 		break;
 	case BLKTRACETEARDOWN:
-		ret = __blk_trace_remove(q);
+		ret = blk_trace_remove(q);
 		break;
 	default:
 		ret = -ENOTTY;
 		break;
 	}
-
-	mutex_unlock(&q->debugfs_mutex);
 	return ret;
 }