Merge "iommu/iommu-debug: Provide debugfs for iommu_reg_{read,write}" into msm-4.8 (6529900a) · Commits · e / devices / android_kernel_fairphone_FP3

drivers/iommu/iommu-debug.c

+105 −0

Original line number	Diff line number	Diff line
		@@ -35,6 +35,7 @@ struct iommu_debug_attachment {
		struct device *dev;
		struct dentry *dentry;
		struct list_head list;
		unsigned long reg_offset;
		};

		static int iommu_debug_attachment_info_show(struct seq_file s, void ignored)
		@@ -93,6 +94,84 @@ iommu_debug_attachment_trigger_fault_fops = {
		.write = iommu_debug_attachment_trigger_fault_write,
		};

		static ssize_t iommu_debug_attachment_reg_offset_write(
		struct file file, const char __user ubuf, size_t count,
		loff_t *offset)
		{
		struct iommu_debug_attachment *attach = file->private_data;
		unsigned long reg_offset;

		if (kstrtoul_from_user(ubuf, count, 0, &reg_offset)) {
		pr_err("Invalid reg_offset format\n");
		return -EFAULT;
		}

		attach->reg_offset = reg_offset;

		return count;
		}

		static const struct file_operations iommu_debug_attachment_reg_offset_fops = {
		.open = simple_open,
		.write = iommu_debug_attachment_reg_offset_write,
		};

		static ssize_t iommu_debug_attachment_reg_read_read(
		struct file file, char __user ubuf, size_t count, loff_t *offset)
		{
		struct iommu_debug_attachment *attach = file->private_data;
		unsigned long val;
		char *val_str;
		ssize_t val_str_len;

		if (*offset)
		return 0;

		val = iommu_reg_read(attach->domain, attach->reg_offset);
		val_str = kasprintf(GFP_KERNEL, "0x%lx\n", val);
		if (!val_str)
		return -ENOMEM;
		val_str_len = strlen(val_str);

		if (copy_to_user(ubuf, val_str, val_str_len)) {
		pr_err("copy_to_user failed\n");
		val_str_len = -EFAULT;
		goto out;
		}
		offset = 1; / non-zero means we're done */

		out:
		kfree(val_str);
		return val_str_len;
		}

		static const struct file_operations iommu_debug_attachment_reg_read_fops = {
		.open = simple_open,
		.read = iommu_debug_attachment_reg_read_read,
		};

		static ssize_t iommu_debug_attachment_reg_write_write(
		struct file file, const char __user ubuf, size_t count,
		loff_t *offset)
		{
		struct iommu_debug_attachment *attach = file->private_data;
		unsigned long val;

		if (kstrtoul_from_user(ubuf, count, 0, &val)) {
		pr_err("Invalid val format\n");
		return -EFAULT;
		}

		iommu_reg_write(attach->domain, attach->reg_offset, val);

		return count;
		}

		static const struct file_operations iommu_debug_attachment_reg_write_fops = {
		.open = simple_open,
		.write = iommu_debug_attachment_reg_write_write,
		};

		/* should be called with iommu_debug_attachments_lock locked */
		static int iommu_debug_attach_add_debugfs(
		struct iommu_debug_attachment *attach)
		@@ -144,6 +223,32 @@ static int iommu_debug_attach_add_debugfs(
		pr_err("Couldn't create iommu/attachments/%s/trigger_fault debugfs file for domain 0x%p\n",
		dev_name(dev), domain);
		goto err_rmdir;
		}

		if (!debugfs_create_file(
		"reg_offset", S_IRUSR, attach->dentry, attach,
		&iommu_debug_attachment_reg_offset_fops)) {
		pr_err("Couldn't create iommu/attachments/%s/reg_offset debugfs file for domain 0x%p\n",
		dev_name(dev), domain);
		goto err_rmdir;
		}

		if (!debugfs_create_file(
		"reg_read", S_IRUSR, attach->dentry, attach,
		&iommu_debug_attachment_reg_read_fops)) {
		pr_err("Couldn't create iommu/attachments/%s/reg_read debugfs file for domain 0x%p\n",
		dev_name(dev), domain);
		goto err_rmdir;
		}

		if (!debugfs_create_file(
		"reg_write", S_IRUSR, attach->dentry, attach,
		&iommu_debug_attachment_reg_write_fops)) {
		pr_err("Couldn't create iommu/attachments/%s/reg_write debugfs file for domain 0x%p\n",
		dev_name(dev), domain);
		goto err_rmdir;
		}

		return 0;

		err_rmdir: