[PATCH v2 08/15] blktrace: pass blk_user_trace2 to setup functions

Johannes Thumshirn posted 15 patches 6 days, 9 hours ago
[PATCH v2 08/15] blktrace: pass blk_user_trace2 to setup functions
Posted by Johannes Thumshirn 6 days, 9 hours ago
Pass struct blk_user_trace_setup2 to blktrace_setup_finalize(). This
prepares for the incoming extension of the blktrace protocol with a 64bit
act_mask.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
---
 include/linux/blktrace_api.h |  3 ++-
 kernel/trace/blktrace.c      | 27 ++++++++++++++++++++-------
 2 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h
index 122c62e561fc..05c8754456aa 100644
--- a/include/linux/blktrace_api.h
+++ b/include/linux/blktrace_api.h
@@ -14,11 +14,12 @@
 #include <linux/sysfs.h>
 
 struct blk_trace {
+	int version;
 	int trace_state;
 	struct rchan *rchan;
 	unsigned long __percpu *sequence;
 	unsigned char __percpu *msg_data;
-	u16 act_mask;
+	u64 act_mask;
 	u64 start_lba;
 	u64 end_lba;
 	u32 pid;
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index f6a41e9510f6..9cd8eb9e7b4b 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -599,7 +599,7 @@ static struct blk_trace *blk_trace_setup_prepare(struct request_queue *q,
 
 static void blk_trace_setup_finalize(struct request_queue *q,
 				     char *name, struct blk_trace *bt,
-				     struct blk_user_trace_setup *buts)
+				     struct blk_user_trace_setup2 *buts)
 
 {
 	strscpy_pad(buts->name, name, BLKTRACE_BDEV_SIZE);
@@ -631,6 +631,7 @@ int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 		    struct block_device *bdev,
 		    char __user *arg)
 {
+	struct blk_user_trace_setup2 buts2;
 	struct blk_user_trace_setup buts;
 	struct blk_trace *bt;
 	int ret;
@@ -642,6 +643,15 @@ int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 	if (!buts.buf_size || !buts.buf_nr)
 		return -EINVAL;
 
+	buts2 = (struct blk_user_trace_setup2) {
+		.act_mask = buts.act_mask,
+		.buf_size = buts.buf_size,
+		.buf_nr = buts.buf_nr,
+		.start_lba = buts.start_lba,
+		.end_lba = buts.end_lba,
+		.pid = buts.pid,
+	};
+
 	mutex_lock(&q->debugfs_mutex);
 	bt = blk_trace_setup_prepare(q, name, dev, buts.buf_size, buts.buf_nr,
 				     bdev);
@@ -649,7 +659,9 @@ int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 		mutex_unlock(&q->debugfs_mutex);
 		return PTR_ERR(bt);
 	}
-	blk_trace_setup_finalize(q, name, bt, &buts);
+	bt->version = 1;
+	blk_trace_setup_finalize(q, name, bt, &buts2);
+	strcpy(buts.name, buts2.name);
 	mutex_unlock(&q->debugfs_mutex);
 
 	if (copy_to_user(arg, &buts, sizeof(buts))) {
@@ -665,7 +677,7 @@ static int compat_blk_trace_setup(struct request_queue *q, char *name,
 				  dev_t dev, struct block_device *bdev,
 				  char __user *arg)
 {
-	struct blk_user_trace_setup buts;
+	struct blk_user_trace_setup2 buts2;
 	struct compat_blk_user_trace_setup cbuts;
 	struct blk_trace *bt;
 
@@ -675,7 +687,7 @@ static int compat_blk_trace_setup(struct request_queue *q, char *name,
 	if (!cbuts.buf_size || !cbuts.buf_nr)
 		return -EINVAL;
 
-	buts = (struct blk_user_trace_setup) {
+	buts2 = (struct blk_user_trace_setup2) {
 		.act_mask = cbuts.act_mask,
 		.buf_size = cbuts.buf_size,
 		.buf_nr = cbuts.buf_nr,
@@ -685,16 +697,17 @@ static int compat_blk_trace_setup(struct request_queue *q, char *name,
 	};
 
 	mutex_lock(&q->debugfs_mutex);
-	bt = blk_trace_setup_prepare(q, name, dev, buts.buf_size, buts.buf_nr,
+	bt = blk_trace_setup_prepare(q, name, dev, buts2.buf_size, buts2.buf_nr,
 				     bdev);
 	if (IS_ERR(bt)) {
 		mutex_unlock(&q->debugfs_mutex);
 		return PTR_ERR(bt);
 	}
-	blk_trace_setup_finalize(q, name, bt, &buts);
+	bt->version = 1;
+	blk_trace_setup_finalize(q, name, bt, &buts2);
 	mutex_unlock(&q->debugfs_mutex);
 
-	if (copy_to_user(arg, &buts.name, ARRAY_SIZE(buts.name))) {
+	if (copy_to_user(arg, &buts2.name, ARRAY_SIZE(buts2.name))) {
 		blk_trace_remove(q);
 		return -EFAULT;
 	}
-- 
2.51.0
Re: [PATCH v2 08/15] blktrace: pass blk_user_trace2 to setup functions
Posted by Damien Le Moal 18 hours ago
On 9/26/25 00:02, Johannes Thumshirn wrote:
> Pass struct blk_user_trace_setup2 to blktrace_setup_finalize(). This
> prepares for the incoming extension of the blktrace protocol with a 64bit
> act_mask.
> 
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>

Reviewed-by: Damien Le Moal <dlemoal@kernel.org>

One nit below.

> @@ -649,7 +659,9 @@ int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
>  		mutex_unlock(&q->debugfs_mutex);
>  		return PTR_ERR(bt);
>  	}
> -	blk_trace_setup_finalize(q, name, bt, &buts);
> +	bt->version = 1;
> +	blk_trace_setup_finalize(q, name, bt, &buts2);

I wonder if it may not be cleaner to pass the version number to
blk_trace_setup_finalize() and have that function do "bt->version = version;" ?


> +	strcpy(buts.name, buts2.name);
>  	mutex_unlock(&q->debugfs_mutex);
>  
>  	if (copy_to_user(arg, &buts, sizeof(buts))) {
> @@ -665,7 +677,7 @@ static int compat_blk_trace_setup(struct request_queue *q, char *name,
>  				  dev_t dev, struct block_device *bdev,
>  				  char __user *arg)
>  {
> -	struct blk_user_trace_setup buts;
> +	struct blk_user_trace_setup2 buts2;
>  	struct compat_blk_user_trace_setup cbuts;
>  	struct blk_trace *bt;
>  
> @@ -675,7 +687,7 @@ static int compat_blk_trace_setup(struct request_queue *q, char *name,
>  	if (!cbuts.buf_size || !cbuts.buf_nr)
>  		return -EINVAL;
>  
> -	buts = (struct blk_user_trace_setup) {
> +	buts2 = (struct blk_user_trace_setup2) {
>  		.act_mask = cbuts.act_mask,
>  		.buf_size = cbuts.buf_size,
>  		.buf_nr = cbuts.buf_nr,
> @@ -685,16 +697,17 @@ static int compat_blk_trace_setup(struct request_queue *q, char *name,
>  	};
>  
>  	mutex_lock(&q->debugfs_mutex);
> -	bt = blk_trace_setup_prepare(q, name, dev, buts.buf_size, buts.buf_nr,
> +	bt = blk_trace_setup_prepare(q, name, dev, buts2.buf_size, buts2.buf_nr,
>  				     bdev);
>  	if (IS_ERR(bt)) {
>  		mutex_unlock(&q->debugfs_mutex);
>  		return PTR_ERR(bt);
>  	}
> -	blk_trace_setup_finalize(q, name, bt, &buts);
> +	bt->version = 1;
> +	blk_trace_setup_finalize(q, name, bt, &buts2);
>  	mutex_unlock(&q->debugfs_mutex);
>  
> -	if (copy_to_user(arg, &buts.name, ARRAY_SIZE(buts.name))) {
> +	if (copy_to_user(arg, &buts2.name, ARRAY_SIZE(buts2.name))) {
>  		blk_trace_remove(q);
>  		return -EFAULT;
>  	}


-- 
Damien Le Moal
Western Digital Research