[PATCH v4 16/16] blktrace: handle BLKTRACESETUP2 ioctl
From: Johannes Thumshirn <hidden>
Date: 2025-10-20 13:42:41
Also in:
linux-block, lkml
Subsystem:
block layer, the rest, tracing · Maintainers:
Jens Axboe, Linus Torvalds, Steven Rostedt, Masami Hiramatsu
Handle the BLKTRACESETUP2 ioctl, requesting an extended version of the blktrace protocol from user-space. Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Johannes Thumshirn <redacted> --- block/ioctl.c | 1 + kernel/trace/blktrace.c | 36 ++++++++++++++++++++++++++++++++++++ 2 files changed, 37 insertions(+)
diff --git a/block/ioctl.c b/block/ioctl.c
index d7489a56b33c..3927ca4707d0 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c@@ -691,6 +691,7 @@ long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg) /* Incompatible alignment on i386 */ case BLKTRACESETUP: + case BLKTRACESETUP2: return blk_trace_ioctl(bdev, cmd, argp); default: break;
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 75994671d7ee..c4f0b84482ca 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c@@ -748,6 +748,38 @@ int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, } EXPORT_SYMBOL_GPL(blk_trace_setup); +static int blk_trace_setup2(struct request_queue *q, char *name, dev_t dev, + struct block_device *bdev, char __user *arg) +{ + struct blk_user_trace_setup2 buts2; + struct blk_trace *bt; + + if (copy_from_user(&buts2, arg, sizeof(buts2))) + return -EFAULT; + + if (!buts2.buf_size || !buts2.buf_nr) + return -EINVAL; + + if (buts2.flags != 0) + return -EINVAL; + + mutex_lock(&q->debugfs_mutex); + 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, 2, bt, &buts2); + mutex_unlock(&q->debugfs_mutex); + + if (copy_to_user(arg, &buts2, sizeof(buts2))) { + blk_trace_remove(q); + return -EFAULT; + } + return 0; +} + #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) static int compat_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, struct block_device *bdev,
@@ -838,6 +870,10 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) char b[BDEVNAME_SIZE]; switch (cmd) { + case BLKTRACESETUP2: + snprintf(b, sizeof(b), "%pg", bdev); + ret = blk_trace_setup2(q, b, bdev->bd_dev, bdev, arg); + break; case BLKTRACESETUP: snprintf(b, sizeof(b), "%pg", bdev); ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg);
--
2.51.0