block: push BKL into blktrace ioctls
The blktrace driver currently needs the BKL, but
we should not need to take that in the block layer,
so just push it down into the driver itself.
It is quite likely that the BKL is not actually
required in blktrace code and could be removed
in a follow-on patch.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 3b4a695..82499a5 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -552,6 +552,41 @@
}
EXPORT_SYMBOL_GPL(blk_trace_setup);
+#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,
+ char __user *arg)
+{
+ struct blk_user_trace_setup buts;
+ struct compat_blk_user_trace_setup cbuts;
+ int ret;
+
+ if (copy_from_user(&cbuts, arg, sizeof(cbuts)))
+ return -EFAULT;
+
+ buts = (struct blk_user_trace_setup) {
+ .act_mask = cbuts.act_mask,
+ .buf_size = cbuts.buf_size,
+ .buf_nr = cbuts.buf_nr,
+ .start_lba = cbuts.start_lba,
+ .end_lba = cbuts.end_lba,
+ .pid = cbuts.pid,
+ };
+ memcpy(&buts.name, &cbuts.name, 32);
+
+ ret = do_blk_trace_setup(q, name, dev, bdev, &buts);
+ if (ret)
+ return ret;
+
+ if (copy_to_user(arg, &buts.name, 32)) {
+ blk_trace_remove(q);
+ return -EFAULT;
+ }
+
+ return 0;
+}
+#endif
+
int blk_trace_startstop(struct request_queue *q, int start)
{
int ret;
@@ -604,6 +639,7 @@
if (!q)
return -ENXIO;
+ lock_kernel();
mutex_lock(&bdev->bd_mutex);
switch (cmd) {
@@ -611,6 +647,12 @@
bdevname(bdev, b);
ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg);
break;
+#if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64)
+ case BLKTRACESETUP32:
+ bdevname(bdev, b);
+ ret = compat_blk_trace_setup(q, b, bdev->bd_dev, bdev, arg);
+ break;
+#endif
case BLKTRACESTART:
start = 1;
case BLKTRACESTOP:
@@ -625,6 +667,7 @@
}
mutex_unlock(&bdev->bd_mutex);
+ unlock_kernel();
return ret;
}