firmware/efi/dev-path-parser.c

15 static long __init parse_acpi_path(const struct efi_dev_path *node,
22 	if (node->header.length != 12)
26 		'A' + ((node->acpi.hid >> 10) & 0x1f) - 1,
27 		'A' + ((node->acpi.hid >>  5) & 0x1f) - 1,
28 		'A' + ((node->acpi.hid >>  0) & 0x1f) - 1,
29 			node->acpi.hid >> 16);
32 		if (acpi_dev_uid_match(adev, node->acpi.uid))
34 		if (!acpi_device_uid(adev) && node->acpi.uid == 0)
57 static long __init parse_pci_path(const struct efi_dev_path *node,
62 	if (node->header.length != 6)
67 	devfn = PCI_DEVFN(node->pci.dev, node->pci.fn);
77  * Insert parsers for further node types here.
79  * Each parser takes a pointer to the @node and to the @parent (will be NULL
80  * for the first device path node). If a device corresponding to @node was
89  * Be sure to validate the node length and contents before commencing the
93 static long __init parse_end_path(const struct efi_dev_path *node,
96 	if (node->header.length != 4)
98 	if (node->header.sub_type != EFI_DEV_END_INSTANCE &&
99 	    node->header.sub_type != EFI_DEV_END_ENTIRE)
105 	return node->header.sub_type;
110  * @node: EFI Device Path
113  * Parse a series of EFI Device Path nodes at @node and find the corresponding
116  * put_device() after use.  The @node pointer is updated to point to the
117  * location immediately after the "End of Hardware Device Path" node.
122  * If a Device Path node is malformed or its corresponding device is not found,
123  * @node is updated to point to this offending node and an ERR_PTR is returned.
128  *	while (!IS_ERR_OR_NULL(dev = efi_get_device_by_path(&node, &len))) {
141  *	%ERR_PTR(-EINVAL) if a node is malformed or exceeds @len,
142  *	%ERR_PTR(-ENOTSUPP) if support for a node type is not yet implemented.
144 struct device * __init efi_get_device_by_path(const struct efi_dev_path **node,
154 		if (*len < 4 || *len < (*node)->header.length)
156 		else if ((*node)->header.type		== EFI_DEV_ACPI &&
157 			 (*node)->header.sub_type	== EFI_DEV_BASIC_ACPI)
158 			ret = parse_acpi_path(*node, parent, &child);
159 		else if ((*node)->header.type		== EFI_DEV_HW &&
160 			 (*node)->header.sub_type	== EFI_DEV_PCI)
161 			ret = parse_pci_path(*node, parent, &child);
162 		else if (((*node)->header.type		== EFI_DEV_END_PATH ||
163 			  (*node)->header.type		== EFI_DEV_END_PATH2))
164 			ret = parse_end_path(*node, parent, &child);
173 		*node  = (void *)*node + (*node)->header.length;
174 		*len  -= (*node)->header.length;