Merge "msm: pm: Add mutex lock for shared data" (8e5775b7) · Commits · e / devices / android_kernel_xiaomi_markw

drivers/power/qcom/msm-pm.c

+33 −12

Original line number	Diff line number	Diff line
		/* Copyright (c) 2010-2016, The Linux Foundation. All rights reserved.
		/* Copyright (c) 2010-2017, The Linux Foundation. All rights reserved.
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License version 2 and
		@@ -87,6 +87,7 @@ static long *msm_pc_debug_counters;

		static cpumask_t retention_cpus;
		static DEFINE_SPINLOCK(retention_lock);
		static DEFINE_MUTEX(msm_pc_debug_mutex);

		static bool msm_pm_is_L1_writeback(void)
		{
		@@ -678,33 +679,48 @@ static ssize_t msm_pc_debug_counters_file_read(struct file *file,
		char __user bufu, size_t count, loff_t ppos)
		{
		struct msm_pc_debug_counters_buffer *data;
		ssize_t ret;

		mutex_lock(&msm_pc_debug_mutex);
		data = file->private_data;

		if (!data)
		return -EINVAL;
		if (!data) {
		ret = -EINVAL;
		goto exit;
		}

		if (!bufu)
		return -EINVAL;
		if (!bufu) {
		ret = -EINVAL;
		goto exit;
		}

		if (!access_ok(VERIFY_WRITE, bufu, count))
		return -EFAULT;
		if (!access_ok(VERIFY_WRITE, bufu, count)) {
		ret = -EFAULT;
		goto exit;
		}

		if (*ppos >= data->len && data->len == 0)
		data->len = msm_pc_debug_counters_copy(data);

		return simple_read_from_buffer(bufu, count, ppos,
		ret = simple_read_from_buffer(bufu, count, ppos,
		data->buf, data->len);
		exit:
		mutex_unlock(&msm_pc_debug_mutex);
		return ret;
		}

		static int msm_pc_debug_counters_file_open(struct inode *inode,
		struct file *file)
		{
		struct msm_pc_debug_counters_buffer *buf;
		int ret = 0;

		mutex_lock(&msm_pc_debug_mutex);

		if (!inode->i_private)
		return -EINVAL;
		if (!inode->i_private) {
		ret = -EINVAL;
		goto exit;
		}

		file->private_data = kzalloc(
		sizeof(struct msm_pc_debug_counters_buffer), GFP_KERNEL);
		@@ -713,19 +729,24 @@ static int msm_pc_debug_counters_file_open(struct inode *inode,
		pr_err("%s: ERROR kmalloc failed to allocate %zu bytes\n",
		__func__, sizeof(struct msm_pc_debug_counters_buffer));

		return -ENOMEM;
		ret = -ENOMEM;
		goto exit;
		}

		buf = file->private_data;
		buf->reg = (long *)inode->i_private;

		return 0;
		exit:
		mutex_unlock(&msm_pc_debug_mutex);
		return ret;
		}

		static int msm_pc_debug_counters_file_close(struct inode *inode,
		struct file *file)
		{
		mutex_lock(&msm_pc_debug_mutex);
		kfree(file->private_data);
		mutex_unlock(&msm_pc_debug_mutex);
		return 0;
		}