diff options
Diffstat (limited to 'drivers/mailbox/mailbox-test.c')
| -rw-r--r-- | drivers/mailbox/mailbox-test.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c index 4555d678fadd..c4a705c30331 100644 --- a/drivers/mailbox/mailbox-test.c +++ b/drivers/mailbox/mailbox-test.c @@ -12,10 +12,12 @@ #include <linux/kernel.h> #include <linux/mailbox_client.h> #include <linux/module.h> +#include <linux/mutex.h> #include <linux/of.h> #include <linux/platform_device.h> #include <linux/poll.h> #include <linux/slab.h> +#include <linux/spinlock.h> #include <linux/uaccess.h> #include <linux/sched/signal.h> @@ -38,6 +40,7 @@ struct mbox_test_device { char *signal; char *message; spinlock_t lock; + struct mutex mutex; wait_queue_head_t waitq; struct fasync_struct *async_queue; struct dentry *root_debugfs_dir; @@ -110,6 +113,8 @@ static ssize_t mbox_test_message_write(struct file *filp, return -EINVAL; } + mutex_lock(&tdev->mutex); + tdev->message = kzalloc(MBOX_MAX_MSG_LEN, GFP_KERNEL); if (!tdev->message) return -ENOMEM; @@ -144,6 +149,8 @@ out: kfree(tdev->message); tdev->signal = NULL; + mutex_unlock(&tdev->mutex); + return ret < 0 ? ret : count; } @@ -392,6 +399,7 @@ static int mbox_test_probe(struct platform_device *pdev) platform_set_drvdata(pdev, tdev); spin_lock_init(&tdev->lock); + mutex_init(&tdev->mutex); if (tdev->rx_channel) { tdev->rx_buffer = devm_kzalloc(&pdev->dev, |