forked from ~ljy/RK356X_SDK_RELEASE

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2023-12-11 d2ccde1c8e90d38cee87a1b0309ad2827f3fd30d 
 kernel/kernel/trace/blktrace.c
....@@ -67,23 +67,22 @@
6767  * Send out a notify message.
6868  */
6969 static void trace_note(struct blk_trace *bt, pid_t pid, int action,
70
-		       const void *data, size_t len,
71
-		       union kernfs_node_id *cgid)
70
+		       const void *data, size_t len, u64 cgid)
7271 {
7372 	struct blk_io_trace *t;
7473 	struct ring_buffer_event *event = NULL;
75
-	struct ring_buffer *buffer = NULL;
76
-	int pc = 0;
74
+	struct trace_buffer *buffer = NULL;
75
+	unsigned int trace_ctx = 0;
7776 	int cpu = smp_processor_id();
7877 	bool blk_tracer = blk_tracer_enabled;
79
-	ssize_t cgid_len = cgid ? sizeof(*cgid) : 0;
78
+	ssize_t cgid_len = cgid ? sizeof(cgid) : 0;
8079 
8180 	if (blk_tracer) {
82
-		buffer = blk_tr->trace_buffer.buffer;
83
-		pc = preempt_count();
81
+		buffer = blk_tr->array_buffer.buffer;
82
+		trace_ctx = tracing_gen_ctx_flags(0);
8483 		event = trace_buffer_lock_reserve(buffer, TRACE_BLK,
8584 						  sizeof(*t) + len + cgid_len,
86
-						  0, pc);
85
+						  trace_ctx);
8786 		if (!event)
8887 			return;
8988 		t = ring_buffer_event_data(event);
....@@ -103,12 +102,12 @@
103102 		t->pid = pid;
104103 		t->cpu = cpu;
105104 		t->pdu_len = len + cgid_len;
106
-		if (cgid)
107
-			memcpy((void *)t + sizeof(*t), cgid, cgid_len);
105
+		if (cgid_len)
106
+			memcpy((void *)t + sizeof(*t), &cgid, cgid_len);
108107 		memcpy((void *) t + sizeof(*t) + cgid_len, data, len);
109108 
110109 		if (blk_tracer)
111
-			trace_buffer_unlock_commit(blk_tr, buffer, event, 0, pc);
110
+			trace_buffer_unlock_commit(blk_tr, buffer, event, trace_ctx);
112111 	}
113112 }
114113 
....@@ -125,7 +124,7 @@
125124 	spin_lock_irqsave(&running_trace_lock, flags);
126125 	list_for_each_entry(bt, &running_trace_list, running_list) {
127126 		trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm,
128
-			   sizeof(tsk->comm), NULL);
127
+			   sizeof(tsk->comm), 0);
129128 	}
130129 	spin_unlock_irqrestore(&running_trace_lock, flags);
131130 }
....@@ -142,7 +141,7 @@
142141 	words[1] = now.tv_nsec;
143142 
144143 	local_irq_save(flags);
145
-	trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words), NULL);
144
+	trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words), 0);
146145 	local_irq_restore(flags);
147146 }
148147 
....@@ -174,10 +173,10 @@
174173 	if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CGROUP))
175174 		blkcg = NULL;
176175 #ifdef CONFIG_BLK_CGROUP
177
-	trace_note(bt, 0, BLK_TN_MESSAGE, buf, n,
178
-		blkcg ? cgroup_get_kernfs_id(blkcg->css.cgroup) : NULL);
176
+	trace_note(bt, current->pid, BLK_TN_MESSAGE, buf, n,
177
+		   blkcg ? cgroup_id(blkcg->css.cgroup) : 1);
179178 #else
180
-	trace_note(bt, 0, BLK_TN_MESSAGE, buf, n, NULL);
179
+	trace_note(bt, current->pid, BLK_TN_MESSAGE, buf, n, 0);
181180 #endif
182181 	local_irq_restore(flags);
183182 }
....@@ -215,18 +214,19 @@
215214  */
216215 static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
217216 		     int op, int op_flags, u32 what, int error, int pdu_len,
218
-		     void *pdu_data, union kernfs_node_id *cgid)
217
+		     void *pdu_data, u64 cgid)
219218 {
220219 	struct task_struct *tsk = current;
221220 	struct ring_buffer_event *event = NULL;
222
-	struct ring_buffer *buffer = NULL;
221
+	struct trace_buffer *buffer = NULL;
223222 	struct blk_io_trace *t;
224223 	unsigned long flags = 0;
225224 	unsigned long *sequence;
225
+	unsigned int trace_ctx = 0;
226226 	pid_t pid;
227
-	int cpu, pc = 0;
227
+	int cpu;
228228 	bool blk_tracer = blk_tracer_enabled;
229
-	ssize_t cgid_len = cgid ? sizeof(*cgid) : 0;
229
+	ssize_t cgid_len = cgid ? sizeof(cgid) : 0;
230230 
231231 	if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer))
232232 		return;
....@@ -252,11 +252,11 @@
252252 	if (blk_tracer) {
253253 		tracing_record_cmdline(current);
254254 
255
-		buffer = blk_tr->trace_buffer.buffer;
256
-		pc = preempt_count();
255
+		buffer = blk_tr->array_buffer.buffer;
256
+		trace_ctx = tracing_gen_ctx_flags(0);
257257 		event = trace_buffer_lock_reserve(buffer, TRACE_BLK,
258258 						  sizeof(*t) + pdu_len + cgid_len,
259
-						  0, pc);
259
+						  trace_ctx);
260260 		if (!event)
261261 			return;
262262 		t = ring_buffer_event_data(event);
....@@ -297,12 +297,12 @@
297297 		t->pdu_len = pdu_len + cgid_len;
298298 
299299 		if (cgid_len)
300
-			memcpy((void *)t + sizeof(*t), cgid, cgid_len);
300
+			memcpy((void *)t + sizeof(*t), &cgid, cgid_len);
301301 		if (pdu_len)
302302 			memcpy((void *)t + sizeof(*t) + cgid_len, pdu_data, pdu_len);
303303 
304304 		if (blk_tracer) {
305
-			trace_buffer_unlock_commit(blk_tr, buffer, event, 0, pc);
305
+			trace_buffer_unlock_commit(blk_tr, buffer, event, trace_ctx);
306306 			return;
307307 		}
308308 	}
....@@ -348,7 +348,8 @@
348348 {
349349 	struct blk_trace *bt;
350350 
351
-	bt = xchg(&q->blk_trace, NULL);
351
+	bt = rcu_replace_pointer(q->blk_trace, NULL,
352
+				 lockdep_is_held(&q->debugfs_mutex));
352353 	if (!bt)
353354 		return -EINVAL;
354355 
....@@ -362,9 +363,9 @@
362363 {
363364 	int ret;
364365 
365
-	mutex_lock(&q->blk_trace_mutex);
366
+	mutex_lock(&q->debugfs_mutex);
366367 	ret = __blk_trace_remove(q);
367
-	mutex_unlock(&q->blk_trace_mutex);
368
+	mutex_unlock(&q->debugfs_mutex);
368369 
369370 	return ret;
370371 }
....@@ -483,11 +484,10 @@
483484 	struct dentry *dir = NULL;
484485 	int ret;
485486 
487
+	lockdep_assert_held(&q->debugfs_mutex);
488
+
486489 	if (!buts->buf_size || !buts->buf_nr)
487490 		return -EINVAL;
488
-
489
-	if (!blk_debugfs_root)
490
-		return -ENOENT;
491491 
492492 	strncpy(buts->name, name, BLKTRACE_BDEV_SIZE);
493493 	buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0';
....@@ -502,7 +502,8 @@
502502 	 * bdev can be NULL, as with scsi-generic, this is a helpful as
503503 	 * we can be.
504504 	 */
505
-	if (q->blk_trace) {
505
+	if (rcu_dereference_protected(q->blk_trace,
506
+				      lockdep_is_held(&q->debugfs_mutex))) {
506507 		pr_warn("Concurrent blktraces are not allowed on %s\n",
507508 			buts->name);
508509 		return -EBUSY;
....@@ -521,21 +522,16 @@
521522 	if (!bt->msg_data)
522523 		goto err;
523524 
524
-#ifdef CONFIG_BLK_DEBUG_FS
525525 	/*
526
-	 * When tracing whole make_request drivers (multiqueue) block devices,
527
-	 * reuse the existing debugfs directory created by the block layer on
528
-	 * init. For request-based block devices, all partitions block devices,
526
+	 * When tracing the whole disk reuse the existing debugfs directory
527
+	 * created by the block layer on init. For partitions block devices,
529528 	 * and scsi-generic block devices we create a temporary new debugfs
530529 	 * directory that will be removed once the trace ends.
531530 	 */
532
-	if (q->mq_ops && bdev && bdev == bdev->bd_contains)
531
+	if (bdev && !bdev_is_partition(bdev))
533532 		dir = q->debugfs_dir;
534533 	else
535
-#endif
536534 		bt->dir = dir = debugfs_create_dir(buts->name, blk_debugfs_root);
537
-	if (!dir)
538
-		goto err;
539535 
540536 	/*
541537 	 * As blktrace relies on debugfs for its interface the debugfs directory
....@@ -556,12 +552,8 @@
556552 	ret = -EIO;
557553 	bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt,
558554 					       &blk_dropped_fops);
559
-	if (!bt->dropped_file)
560
-		goto err;
561555 
562556 	bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops);
563
-	if (!bt->msg_file)
564
-		goto err;
565557 
566558 	bt->rchan = relay_open("trace", dir, buts->buf_size,
567559 				buts->buf_nr, &blk_relay_callbacks, bt);
....@@ -583,10 +575,7 @@
583575 	bt->pid = buts->pid;
584576 	bt->trace_state = Blktrace_setup;
585577 
586
-	ret = -EBUSY;
587
-	if (cmpxchg(&q->blk_trace, NULL, bt))
588
-		goto err;
589
-
578
+	rcu_assign_pointer(q->blk_trace, bt);
590579 	get_probe_ref();
591580 
592581 	ret = 0;
....@@ -623,9 +612,9 @@
623612 {
624613 	int ret;
625614 
626
-	mutex_lock(&q->blk_trace_mutex);
615
+	mutex_lock(&q->debugfs_mutex);
627616 	ret = __blk_trace_setup(q, name, dev, bdev, arg);
628
-	mutex_unlock(&q->blk_trace_mutex);
617
+	mutex_unlock(&q->debugfs_mutex);
629618 
630619 	return ret;
631620 }
....@@ -671,7 +660,7 @@
671660 	struct blk_trace *bt;
672661 
673662 	bt = rcu_dereference_protected(q->blk_trace,
674
-				       lockdep_is_held(&q->blk_trace_mutex));
663
+				       lockdep_is_held(&q->debugfs_mutex));
675664 	if (bt == NULL)
676665 		return -EINVAL;
677666 
....@@ -711,9 +700,9 @@
711700 {
712701 	int ret;
713702 
714
-	mutex_lock(&q->blk_trace_mutex);
703
+	mutex_lock(&q->debugfs_mutex);
715704 	ret = __blk_trace_startstop(q, start);
716
-	mutex_unlock(&q->blk_trace_mutex);
705
+	mutex_unlock(&q->debugfs_mutex);
717706 
718707 	return ret;
719708 }
....@@ -742,7 +731,7 @@
742731 	if (!q)
743732 		return -ENXIO;
744733 
745
-	mutex_lock(&q->blk_trace_mutex);
734
+	mutex_lock(&q->debugfs_mutex);
746735 
747736 	switch (cmd) {
748737 	case BLKTRACESETUP:
....@@ -757,6 +746,7 @@
757746 #endif
758747 	case BLKTRACESTART:
759748 		start = 1;
749
+		fallthrough;
760750 	case BLKTRACESTOP:
761751 		ret = __blk_trace_startstop(q, start);
762752 		break;
....@@ -768,7 +758,7 @@
768758 		break;
769759 	}
770760 
771
-	mutex_unlock(&q->blk_trace_mutex);
761
+	mutex_unlock(&q->debugfs_mutex);
772762 	return ret;
773763 }
774764 
....@@ -779,44 +769,42 @@
779769  **/
780770 void blk_trace_shutdown(struct request_queue *q)
781771 {
782
-	mutex_lock(&q->blk_trace_mutex);
772
+	mutex_lock(&q->debugfs_mutex);
783773 	if (rcu_dereference_protected(q->blk_trace,
784
-				      lockdep_is_held(&q->blk_trace_mutex))) {
774
+				      lockdep_is_held(&q->debugfs_mutex))) {
785775 		__blk_trace_startstop(q, 0);
786776 		__blk_trace_remove(q);
787777 	}
788778 
789
-	mutex_unlock(&q->blk_trace_mutex);
779
+	mutex_unlock(&q->debugfs_mutex);
790780 }
791781 
792782 #ifdef CONFIG_BLK_CGROUP
793
-static union kernfs_node_id *
794
-blk_trace_bio_get_cgid(struct request_queue *q, struct bio *bio)
783
+static u64 blk_trace_bio_get_cgid(struct request_queue *q, struct bio *bio)
795784 {
796785 	struct blk_trace *bt;
797786 
798787 	/* We don't use the 'bt' value here except as an optimization... */
799788 	bt = rcu_dereference_protected(q->blk_trace, 1);
800789 	if (!bt || !(blk_tracer_flags.val & TRACE_BLK_OPT_CGROUP))
801
-		return NULL;
790
+		return 0;
802791 
803
-	if (!bio->bi_css)
804
-		return NULL;
805
-	return cgroup_get_kernfs_id(bio->bi_css->cgroup);
792
+	if (!bio->bi_blkg)
793
+		return 0;
794
+	return cgroup_id(bio_blkcg(bio)->css.cgroup);
806795 }
807796 #else
808
-static union kernfs_node_id *
809
-blk_trace_bio_get_cgid(struct request_queue *q, struct bio *bio)
797
+static u64 blk_trace_bio_get_cgid(struct request_queue *q, struct bio *bio)
810798 {
811
-	return NULL;
799
+	return 0;
812800 }
813801 #endif
814802 
815
-static union kernfs_node_id *
803
+static u64
816804 blk_trace_request_get_cgid(struct request_queue *q, struct request *rq)
817805 {
818806 	if (!rq->bio)
819
-		return NULL;
807
+		return 0;
820808 	/* Use the first bio */
821809 	return blk_trace_bio_get_cgid(q, rq->bio);
822810 }
....@@ -838,8 +826,7 @@
838826  *
839827  **/
840828 static void blk_add_trace_rq(struct request *rq, int error,
841
-			     unsigned int nr_bytes, u32 what,
842
-			     union kernfs_node_id *cgid)
829
+			     unsigned int nr_bytes, u32 what, u64 cgid)
843830 {
844831 	struct blk_trace *bt;
845832 
....@@ -871,6 +858,13 @@
871858 				   struct request_queue *q, struct request *rq)
872859 {
873860 	blk_add_trace_rq(rq, 0, blk_rq_bytes(rq), BLK_TA_ISSUE,
861
+			 blk_trace_request_get_cgid(q, rq));
862
+}
863
+
864
+static void blk_add_trace_rq_merge(void *ignore,
865
+				   struct request_queue *q, struct request *rq)
866
+{
867
+	blk_add_trace_rq(rq, 0, blk_rq_bytes(rq), BLK_TA_BACKMERGE,
874868 			 blk_trace_request_get_cgid(q, rq));
875869 }
876870 
....@@ -925,10 +919,10 @@
925919 }
926920 
927921 static void blk_add_trace_bio_complete(void *ignore,
928
-				       struct request_queue *q, struct bio *bio,
929
-				       int error)
922
+				       struct request_queue *q, struct bio *bio)
930923 {
931
-	blk_add_trace_bio(q, bio, BLK_TA_COMPLETE, error);
924
+	blk_add_trace_bio(q, bio, BLK_TA_COMPLETE,
925
+			  blk_status_to_errno(bio->bi_status));
932926 }
933927 
934928 static void blk_add_trace_bio_backmerge(void *ignore,
....@@ -966,7 +960,7 @@
966960 		bt = rcu_dereference(q->blk_trace);
967961 		if (bt)
968962 			__blk_add_trace(bt, 0, 0, rw, 0, BLK_TA_GETRQ, 0, 0,
969
-					NULL, NULL);
963
+					NULL, 0);
970964 		rcu_read_unlock();
971965 	}
972966 }
....@@ -985,7 +979,7 @@
985979 		bt = rcu_dereference(q->blk_trace);
986980 		if (bt)
987981 			__blk_add_trace(bt, 0, 0, rw, 0, BLK_TA_SLEEPRQ,
988
-					0, 0, NULL, NULL);
982
+					0, 0, NULL, 0);
989983 		rcu_read_unlock();
990984 	}
991985 }
....@@ -997,7 +991,7 @@
997991 	rcu_read_lock();
998992 	bt = rcu_dereference(q->blk_trace);
999993 	if (bt)
1000
-		__blk_add_trace(bt, 0, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL, NULL);
994
+		__blk_add_trace(bt, 0, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL, 0);
1001995 	rcu_read_unlock();
1002996 }
1003997 
....@@ -1017,7 +1011,7 @@
10171011 		else
10181012 			what = BLK_TA_UNPLUG_TIMER;
10191013 
1020
-		__blk_add_trace(bt, 0, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu, NULL);
1014
+		__blk_add_trace(bt, 0, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu, 0);
10211015 	}
10221016 	rcu_read_unlock();
10231017 }
....@@ -1158,6 +1152,8 @@
11581152 	WARN_ON(ret);
11591153 	ret = register_trace_block_rq_issue(blk_add_trace_rq_issue, NULL);
11601154 	WARN_ON(ret);
1155
+	ret = register_trace_block_rq_merge(blk_add_trace_rq_merge, NULL);
1156
+	WARN_ON(ret);
11611157 	ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL);
11621158 	WARN_ON(ret);
11631159 	ret = register_trace_block_rq_complete(blk_add_trace_rq_complete, NULL);
....@@ -1204,6 +1200,7 @@
12041200 	unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL);
12051201 	unregister_trace_block_rq_complete(blk_add_trace_rq_complete, NULL);
12061202 	unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL);
1203
+	unregister_trace_block_rq_merge(blk_add_trace_rq_merge, NULL);
12071204 	unregister_trace_block_rq_issue(blk_add_trace_rq_issue, NULL);
12081205 	unregister_trace_block_rq_insert(blk_add_trace_rq_insert, NULL);
12091206 
....@@ -1256,19 +1253,17 @@
12561253 
12571254 static inline const void *pdu_start(const struct trace_entry *ent, bool has_cg)
12581255 {
1259
-	return (void *)(te_blk_io_trace(ent) + 1) +
1260
-		(has_cg ? sizeof(union kernfs_node_id) : 0);
1256
+	return (void *)(te_blk_io_trace(ent) + 1) + (has_cg ? sizeof(u64) : 0);
12611257 }
12621258 
1263
-static inline const void *cgid_start(const struct trace_entry *ent)
1259
+static inline u64 t_cgid(const struct trace_entry *ent)
12641260 {
1265
-	return (void *)(te_blk_io_trace(ent) + 1);
1261
+	return *(u64 *)(te_blk_io_trace(ent) + 1);
12661262 }
12671263 
12681264 static inline int pdu_real_len(const struct trace_entry *ent, bool has_cg)
12691265 {
1270
-	return te_blk_io_trace(ent)->pdu_len -
1271
-			(has_cg ? sizeof(union kernfs_node_id) : 0);
1266
+	return te_blk_io_trace(ent)->pdu_len - (has_cg ? sizeof(u64) : 0);
12721267 }
12731268 
12741269 static inline u32 t_action(const struct trace_entry *ent)
....@@ -1330,7 +1325,7 @@
13301325 
13311326 	fill_rwbs(rwbs, t);
13321327 	if (has_cg) {
1333
-		const union kernfs_node_id *id = cgid_start(iter->ent);
1328
+		u64 id = t_cgid(iter->ent);
13341329 
13351330 		if (blk_tracer_flags.val & TRACE_BLK_OPT_CGNAME) {
13361331 			char blkcg_name_buf[NAME_MAX + 1] = "<...>";
....@@ -1340,11 +1335,25 @@
13401335 			trace_seq_printf(&iter->seq, "%3d,%-3d %s %2s %3s ",
13411336 				 MAJOR(t->device), MINOR(t->device),
13421337 				 blkcg_name_buf, act, rwbs);
1343
-		} else
1338
+		} else {
1339
+			/*
1340
+			 * The cgid portion used to be "INO,GEN".  Userland
1341
+			 * builds a FILEID_INO32_GEN fid out of them and
1342
+			 * opens the cgroup using open_by_handle_at(2).
1343
+			 * While 32bit ino setups are still the same, 64bit
1344
+			 * ones now use the 64bit ino as the whole ID and
1345
+			 * no longer use generation.
1346
+			 *
1347
+			 * Regarldess of the content, always output
1348
+			 * "LOW32,HIGH32" so that FILEID_INO32_GEN fid can
1349
+			 * be mapped back to @id on both 64 and 32bit ino
1350
+			 * setups.  See __kernfs_fh_to_dentry().
1351
+			 */
13441352 			trace_seq_printf(&iter->seq,
1345
-				 "%3d,%-3d %x,%-x %2s %3s ",
1353
+				 "%3d,%-3d %llx,%-llx %2s %3s ",
13461354 				 MAJOR(t->device), MINOR(t->device),
1347
-				 id->ino, id->generation, act, rwbs);
1355
+				 id & U32_MAX, id >> 32, act, rwbs);
1356
+		}
13481357 	} else
13491358 		trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ",
13501359 				 MAJOR(t->device), MINOR(t->device), act, rwbs);
....@@ -1657,7 +1666,8 @@
16571666 {
16581667 	struct blk_trace *bt;
16591668 
1660
-	bt = xchg(&q->blk_trace, NULL);
1669
+	bt = rcu_replace_pointer(q->blk_trace, NULL,
1670
+				 lockdep_is_held(&q->debugfs_mutex));
16611671 	if (bt == NULL)
16621672 		return -EINVAL;
16631673 
....@@ -1697,10 +1707,7 @@
16971707 
16981708 	blk_trace_setup_lba(bt, bdev);
16991709 
1700
-	ret = -EBUSY;
1701
-	if (cmpxchg(&q->blk_trace, NULL, bt))
1702
-		goto free_bt;
1703
-
1710
+	rcu_assign_pointer(q->blk_trace, bt);
17041711 	get_probe_ref();
17051712 	return 0;
17061713 
....@@ -1829,13 +1836,11 @@
18291836 					 struct device_attribute *attr,
18301837 					 char *buf)
18311838 {
1832
-	struct hd_struct *p = dev_to_part(dev);
1839
+	struct block_device *bdev = bdget_part(dev_to_part(dev));
18331840 	struct request_queue *q;
1834
-	struct block_device *bdev;
18351841 	struct blk_trace *bt;
18361842 	ssize_t ret = -ENXIO;
18371843 
1838
-	bdev = bdget(part_devt(p));
18391844 	if (bdev == NULL)
18401845 		goto out;
18411846 
....@@ -1843,10 +1848,10 @@
18431848 	if (q == NULL)
18441849 		goto out_bdput;
18451850 
1846
-	mutex_lock(&q->blk_trace_mutex);
1851
+	mutex_lock(&q->debugfs_mutex);
18471852 
18481853 	bt = rcu_dereference_protected(q->blk_trace,
1849
-				       lockdep_is_held(&q->blk_trace_mutex));
1854
+				       lockdep_is_held(&q->debugfs_mutex));
18501855 	if (attr == &dev_attr_enable) {
18511856 		ret = sprintf(buf, "%u\n", !!bt);
18521857 		goto out_unlock_bdev;
....@@ -1864,7 +1869,7 @@
18641869 		ret = sprintf(buf, "%llu\n", bt->end_lba);
18651870 
18661871 out_unlock_bdev:
1867
-	mutex_unlock(&q->blk_trace_mutex);
1872
+	mutex_unlock(&q->debugfs_mutex);
18681873 out_bdput:
18691874 	bdput(bdev);
18701875 out:
....@@ -1877,7 +1882,6 @@
18771882 {
18781883 	struct block_device *bdev;
18791884 	struct request_queue *q;
1880
-	struct hd_struct *p;
18811885 	struct blk_trace *bt;
18821886 	u64 value;
18831887 	ssize_t ret = -EINVAL;
....@@ -1897,9 +1901,7 @@
18971901 		goto out;
18981902 
18991903 	ret = -ENXIO;
1900
-
1901
-	p = dev_to_part(dev);
1902
-	bdev = bdget(part_devt(p));
1904
+	bdev = bdget_part(dev_to_part(dev));
19031905 	if (bdev == NULL)
19041906 		goto out;
19051907 
....@@ -1907,10 +1909,10 @@
19071909 	if (q == NULL)
19081910 		goto out_bdput;
19091911 
1910
-	mutex_lock(&q->blk_trace_mutex);
1912
+	mutex_lock(&q->debugfs_mutex);
19111913 
19121914 	bt = rcu_dereference_protected(q->blk_trace,
1913
-				       lockdep_is_held(&q->blk_trace_mutex));
1915
+				       lockdep_is_held(&q->debugfs_mutex));
19141916 	if (attr == &dev_attr_enable) {
19151917 		if (!!value == !!bt) {
19161918 			ret = 0;
....@@ -1927,7 +1929,7 @@
19271929 	if (bt == NULL) {
19281930 		ret = blk_trace_setup_queue(q, bdev);
19291931 		bt = rcu_dereference_protected(q->blk_trace,
1930
-				lockdep_is_held(&q->blk_trace_mutex));
1932
+				lockdep_is_held(&q->debugfs_mutex));
19311933 	}
19321934 
19331935 	if (ret == 0) {
....@@ -1942,7 +1944,7 @@
19421944 	}
19431945 
19441946 out_unlock_bdev:
1945
-	mutex_unlock(&q->blk_trace_mutex);
1947
+	mutex_unlock(&q->debugfs_mutex);
19461948 out_bdput:
19471949 	bdput(bdev);
19481950 out: