Merge "drm/msm: protect register dumps and debugfs with mutex" (349c988a) · Commits · e / devices / android_kernel_sony_msm8998

drivers/gpu/drm/msm/sde_dbg.c

+52 −12

Original line number	Diff line number	Diff line
		@@ -153,6 +153,7 @@ struct sde_dbg_vbif_debug_bus {
		* @reg_base_list: list of register dumping regions
		* @root: base debugfs root
		* @dev: device pointer
		* @mutex: mutex to serialize access to serialze dumps, debugfs access
		* @power_ctrl: callback structure for enabling power for reading hw registers
		* @req_dump_blks: list of blocks requested for dumping
		* @panic_on_err: whether to kernel panic after triggering dump via debugfs
		@@ -167,6 +168,7 @@ static struct sde_dbg_base {
		struct list_head reg_base_list;
		struct dentry *root;
		struct device *dev;
		struct mutex mutex;
		struct sde_dbg_power_ctrl power_ctrl;

		struct sde_dbg_reg_base *req_dump_blks[SDE_DBG_BASE_MAX];
		@@ -1450,6 +1452,8 @@ static void _sde_dump_array(struct sde_dbg_reg_base *blk_arr[],
		{
		int i;

		mutex_lock(&sde_dbg_base.mutex);

		for (i = 0; i < len; i++) {
		if (blk_arr[i] != NULL)
		_sde_dump_reg_by_ranges(blk_arr[i],
		@@ -1466,6 +1470,8 @@ static void _sde_dump_array(struct sde_dbg_reg_base *blk_arr[],

		if (do_panic && sde_dbg_base.panic_on_err)
		panic(name);

		mutex_unlock(&sde_dbg_base.mutex);
		}

		/**
		@@ -1663,6 +1669,7 @@ int sde_dbg_init(struct dentry debugfs_root, struct device dev,
		{
		int i;

		mutex_init(&sde_dbg_base.mutex);
		INIT_LIST_HEAD(&sde_dbg_base.reg_base_list);
		sde_dbg_base.dev = dev;
		sde_dbg_base.power_ctrl = *power_ctrl;
		@@ -1718,6 +1725,7 @@ void sde_dbg_destroy(void)
		sde_dbg_base_evtlog = NULL;
		sde_evtlog_destroy(sde_dbg_base.evtlog);
		sde_dbg_base.evtlog = NULL;
		mutex_destroy(&sde_dbg_base.mutex);
		}

		/**
		@@ -1730,11 +1738,14 @@ static int sde_dbg_reg_base_release(struct inode inode, struct file file)
		{
		struct sde_dbg_reg_base *dbg = file->private_data;

		mutex_lock(&sde_dbg_base.mutex);
		if (dbg && dbg->buf) {
		kfree(dbg->buf);
		dbg->buf_len = 0;
		dbg->buf = NULL;
		}
		mutex_unlock(&sde_dbg_base.mutex);

		return 0;
		}

		@@ -1753,6 +1764,7 @@ static ssize_t sde_dbg_reg_base_offset_write(struct file *file,
		u32 off = 0;
		u32 cnt = DEFAULT_BASE_REG_CNT;
		char buf[24];
		ssize_t rc = count;

		if (!dbg)
		return -ENODEV;
		@@ -1768,24 +1780,33 @@ static ssize_t sde_dbg_reg_base_offset_write(struct file *file,
		if (sscanf(buf, "%x %x", &off, &cnt) != 2)
		return -EFAULT;

		if (off > dbg->max_offset)
		return -EINVAL;
		mutex_lock(&sde_dbg_base.mutex);
		if (off > dbg->max_offset) {
		rc = -EINVAL;
		goto exit;
		}

		if (off % sizeof(u32))
		return -EINVAL;
		if (off % sizeof(u32)) {
		rc = -EINVAL;
		goto exit;
		}

		if (cnt > (dbg->max_offset - off))
		cnt = dbg->max_offset - off;

		if (cnt % sizeof(u32))
		return -EINVAL;
		if (cnt % sizeof(u32)) {
		rc = -EINVAL;
		goto exit;
		}

		dbg->off = off;
		dbg->cnt = cnt;

		exit:
		mutex_unlock(&sde_dbg_base.mutex);
		pr_debug("offset=%x cnt=%x\n", off, cnt);

		return count;
		return rc;
		}

		/**
		@@ -1808,14 +1829,20 @@ static ssize_t sde_dbg_reg_base_offset_read(struct file *file,
		if (*ppos)
		return 0; /* the end */

		mutex_lock(&sde_dbg_base.mutex);
		len = snprintf(buf, sizeof(buf), "0x%08zx %zx\n", dbg->off, dbg->cnt);
		if (len < 0 \|\| len >= sizeof(buf))
		if (len < 0 \|\| len >= sizeof(buf)) {
		mutex_unlock(&sde_dbg_base.mutex);
		return 0;
		}

		if ((count < sizeof(buf)) \|\| copy_to_user(buff, buf, len))
		if ((count < sizeof(buf)) \|\| copy_to_user(buff, buf, len)) {
		mutex_unlock(&sde_dbg_base.mutex);
		return -EFAULT;
		}

		ppos += len; / increase offset */
		mutex_unlock(&sde_dbg_base.mutex);

		return len;
		}
		@@ -1851,8 +1878,11 @@ static ssize_t sde_dbg_reg_base_reg_write(struct file *file,
		if (cnt < 2)
		return -EFAULT;

		if (off >= dbg->max_offset)
		mutex_lock(&sde_dbg_base.mutex);
		if (off >= dbg->max_offset) {
		mutex_unlock(&sde_dbg_base.mutex);
		return -EFAULT;
		}

		_sde_dbg_enable_power(true);

		@@ -1860,6 +1890,8 @@ static ssize_t sde_dbg_reg_base_reg_write(struct file *file,

		_sde_dbg_enable_power(false);

		mutex_unlock(&sde_dbg_base.mutex);

		pr_debug("addr=%zx data=%x\n", off, data);

		return count;
		@@ -1883,6 +1915,7 @@ static ssize_t sde_dbg_reg_base_reg_read(struct file *file,
		return -ENODEV;
		}

		mutex_lock(&sde_dbg_base.mutex);
		if (!dbg->buf) {
		char *hwbuf;
		char dump_buf[64];
		@@ -1897,12 +1930,15 @@ static ssize_t sde_dbg_reg_base_reg_read(struct file *file,

		dbg->buf = kzalloc(dbg->buf_len, GFP_KERNEL);

		if (!dbg->buf)
		if (!dbg->buf) {
		mutex_unlock(&sde_dbg_base.mutex);
		return -ENOMEM;
		}

		hwbuf = kzalloc(ROW_BYTES, GFP_KERNEL);
		if (!hwbuf) {
		kfree(dbg->buf);
		mutex_unlock(&sde_dbg_base.mutex);
		return -ENOMEM;
		}

		@@ -1934,16 +1970,20 @@ static ssize_t sde_dbg_reg_base_reg_read(struct file *file,
		kfree(hwbuf);
		}

		if (*ppos >= dbg->buf_len)
		if (*ppos >= dbg->buf_len) {
		mutex_unlock(&sde_dbg_base.mutex);
		return 0; /* done reading */
		}

		len = min(count, dbg->buf_len - (size_t) *ppos);
		if (copy_to_user(user_buf, dbg->buf + *ppos, len)) {
		mutex_unlock(&sde_dbg_base.mutex);
		pr_err("failed to copy to user\n");
		return -EFAULT;
		}

		ppos += len; / increase offset */
		mutex_unlock(&sde_dbg_base.mutex);

		return len;
		}