[linux-block.git] / include / linux / bootconfig.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_XBC_H
#define _LINUX_XBC_H
/*
 * Extra Boot Config
 * Copyright (C) 2019 Linaro Ltd.
 * Author: Masami Hiramatsu <mhiramat@kernel.org>
 */

#ifdef __KERNEL__
#include <linux/kernel.h>
#include <linux/types.h>
#else /* !__KERNEL__ */
/*
 * NOTE: This is only for tools/bootconfig, because tools/bootconfig will
 * run the parser sanity test.
 * This does NOT mean linux/bootconfig.h is available in the user space.
 * However, if you change this file, please make sure the tools/bootconfig
 * has no issue on building and running.
 */
#endif

#define BOOTCONFIG_MAGIC	"#BOOTCONFIG\n"
#define BOOTCONFIG_MAGIC_LEN	12
#define BOOTCONFIG_ALIGN_SHIFT	2
#define BOOTCONFIG_ALIGN	(1 << BOOTCONFIG_ALIGN_SHIFT)
#define BOOTCONFIG_ALIGN_MASK	(BOOTCONFIG_ALIGN - 1)

/**
 * xbc_calc_checksum() - Calculate checksum of bootconfig
 * @data: Bootconfig data.
 * @size: The size of the bootconfig data.
 *
 * Calculate the checksum value of the bootconfig data.
 * The checksum will be used with the BOOTCONFIG_MAGIC and the size for
 * embedding the bootconfig in the initrd image.
 */
static inline __init uint32_t xbc_calc_checksum(void *data, uint32_t size)
{
	unsigned char *p = data;
	uint32_t ret = 0;

	while (size--)
		ret += *p++;

	return ret;
}

/* XBC tree node */
struct xbc_node {
	uint16_t next;
	uint16_t child;
	uint16_t parent;
	uint16_t data;
} __attribute__ ((__packed__));

#define XBC_KEY		0
#define XBC_VALUE	(1 << 15)
/* Maximum size of boot config is 32KB - 1 */
#define XBC_DATA_MAX	(XBC_VALUE - 1)

#define XBC_NODE_MAX	8192
#define XBC_KEYLEN_MAX	256
#define XBC_DEPTH_MAX	16

/* Node tree access raw APIs */
struct xbc_node * __init xbc_root_node(void);
int __init xbc_node_index(struct xbc_node *node);
struct xbc_node * __init xbc_node_get_parent(struct xbc_node *node);
struct xbc_node * __init xbc_node_get_child(struct xbc_node *node);
struct xbc_node * __init xbc_node_get_next(struct xbc_node *node);
const char * __init xbc_node_get_data(struct xbc_node *node);

/**
 * xbc_node_is_value() - Test the node is a value node
 * @node: An XBC node.
 *
 * Test the @node is a value node and return true if a value node, false if not.
 */
static inline __init bool xbc_node_is_value(struct xbc_node *node)
{
	return node->data & XBC_VALUE;
}

/**
 * xbc_node_is_key() - Test the node is a key node
 * @node: An XBC node.
 *
 * Test the @node is a key node and return true if a key node, false if not.
 */
static inline __init bool xbc_node_is_key(struct xbc_node *node)
{
	return !xbc_node_is_value(node);
}

/**
 * xbc_node_is_array() - Test the node is an arraied value node
 * @node: An XBC node.
 *
 * Test the @node is an arraied value node.
 */
static inline __init bool xbc_node_is_array(struct xbc_node *node)
{
	return xbc_node_is_value(node) && node->child != 0;
}

/**
 * xbc_node_is_leaf() - Test the node is a leaf key node
 * @node: An XBC node.
 *
 * Test the @node is a leaf key node which is a key node and has a value node
 * or no child. Returns true if it is a leaf node, or false if not.
 * Note that the leaf node can have subkey nodes in addition to the
 * value node.
 */
static inline __init bool xbc_node_is_leaf(struct xbc_node *node)
{
	return xbc_node_is_key(node) &&
		(!node->child || xbc_node_is_value(xbc_node_get_child(node)));
}

/* Tree-based key-value access APIs */
struct xbc_node * __init xbc_node_find_subkey(struct xbc_node *parent,
					     const char *key);

const char * __init xbc_node_find_value(struct xbc_node *parent,
					const char *key,
					struct xbc_node **vnode);

struct xbc_node * __init xbc_node_find_next_leaf(struct xbc_node *root,
						 struct xbc_node *leaf);

const char * __init xbc_node_find_next_key_value(struct xbc_node *root,
						 struct xbc_node **leaf);

/**
 * xbc_find_value() - Find a value which matches the key
 * @key: Search key
 * @vnode: A container pointer of XBC value node.
 *
 * Search a value whose key matches @key from whole of XBC tree and return
 * the value if found. Found value node is stored in *@vnode.
 * Note that this can return 0-length string and store NULL in *@vnode for
 * key-only (non-value) entry.
 */
static inline const char * __init
xbc_find_value(const char *key, struct xbc_node **vnode)
{
	return xbc_node_find_value(NULL, key, vnode);
}

/**
 * xbc_find_node() - Find a node which matches the key
 * @key: Search key
 *
 * Search a (key) node whose key matches @key from whole of XBC tree and
 * return the node if found. If not found, returns NULL.
 */
static inline struct xbc_node * __init xbc_find_node(const char *key)
{
	return xbc_node_find_subkey(NULL, key);
}

/**
 * xbc_node_get_subkey() - Return the first subkey node if exists
 * @node: Parent node
 *
 * Return the first subkey node of the @node. If the @node has no child
 * or only value node, this will return NULL.
 */
static inline struct xbc_node * __init xbc_node_get_subkey(struct xbc_node *node)
{
	struct xbc_node *child = xbc_node_get_child(node);

	if (child && xbc_node_is_value(child))
		return xbc_node_get_next(child);
	else
		return child;
}

/**
 * xbc_array_for_each_value() - Iterate value nodes on an array
 * @anode: An XBC arraied value node
 * @value: A value
 *
 * Iterate array value nodes and values starts from @anode. This is expected to
 * be used with xbc_find_value() and xbc_node_find_value(), so that user can
 * process each array entry node.
 */
#define xbc_array_for_each_value(anode, value)				\
	for (value = xbc_node_get_data(anode); anode != NULL ;		\
	     anode = xbc_node_get_child(anode),				\
	     value = anode ? xbc_node_get_data(anode) : NULL)

/**
 * xbc_node_for_each_child() - Iterate child nodes
 * @parent: An XBC node.
 * @child: Iterated XBC node.
 *
 * Iterate child nodes of @parent. Each child nodes are stored to @child.
 * The @child can be mixture of a value node and subkey nodes.
 */
#define xbc_node_for_each_child(parent, child)				\
	for (child = xbc_node_get_child(parent); child != NULL ;	\
	     child = xbc_node_get_next(child))

/**
 * xbc_node_for_each_subkey() - Iterate child subkey nodes
 * @parent: An XBC node.
 * @child: Iterated XBC node.
 *
 * Iterate subkey nodes of @parent. Each child nodes are stored to @child.
 * The @child is only the subkey node.
 */
#define xbc_node_for_each_subkey(parent, child)				\
	for (child = xbc_node_get_subkey(parent); child != NULL ;	\
	     child = xbc_node_get_next(child))

/**
 * xbc_node_for_each_array_value() - Iterate array entries of geven key
 * @node: An XBC node.
 * @key: A key string searched under @node
 * @anode: Iterated XBC node of array entry.
 * @value: Iterated value of array entry.
 *
 * Iterate array entries of given @key under @node. Each array entry node
 * is stored to @anode and @value. If the @node doesn't have @key node,
 * it does nothing.
 * Note that even if the found key node has only one value (not array)
 * this executes block once. However, if the found key node has no value
 * (key-only node), this does nothing. So don't use this for testing the
 * key-value pair existence.
 */
#define xbc_node_for_each_array_value(node, key, anode, value)		\
	for (value = xbc_node_find_value(node, key, &anode); value != NULL; \
	     anode = xbc_node_get_child(anode),				\
	     value = anode ? xbc_node_get_data(anode) : NULL)

/**
 * xbc_node_for_each_key_value() - Iterate key-value pairs under a node
 * @node: An XBC node.
 * @knode: Iterated key node
 * @value: Iterated value string
 *
 * Iterate key-value pairs under @node. Each key node and value string are
 * stored in @knode and @value respectively.
 */
#define xbc_node_for_each_key_value(node, knode, value)			\
	for (knode = NULL, value = xbc_node_find_next_key_value(node, &knode);\
	     knode != NULL; value = xbc_node_find_next_key_value(node, &knode))

/**
 * xbc_for_each_key_value() - Iterate key-value pairs
 * @knode: Iterated key node
 * @value: Iterated value string
 *
 * Iterate key-value pairs in whole XBC tree. Each key node and value string
 * are stored in @knode and @value respectively.
 */
#define xbc_for_each_key_value(knode, value)				\
	xbc_node_for_each_key_value(NULL, knode, value)

/* Compose partial key */
int __init xbc_node_compose_key_after(struct xbc_node *root,
			struct xbc_node *node, char *buf, size_t size);

/**
 * xbc_node_compose_key() - Compose full key string of the XBC node
 * @node: An XBC node.
 * @buf: A buffer to store the key.
 * @size: The size of the @buf.
 *
 * Compose the full-length key of the @node into @buf. Returns the total
 * length of the key stored in @buf. Or returns -EINVAL if @node is NULL,
 * and -ERANGE if the key depth is deeper than max depth.
 */
static inline int __init xbc_node_compose_key(struct xbc_node *node,
					      char *buf, size_t size)
{
	return xbc_node_compose_key_after(NULL, node, buf, size);
}

/* XBC node initializer */
int __init xbc_init(const char *buf, size_t size, const char **emsg, int *epos);

/* XBC node and size information */
int __init xbc_get_info(int *node_size, size_t *data_size);

/* XBC cleanup data structures */
void __init xbc_exit(void);

/* XBC embedded bootconfig data in kernel */
#ifdef CONFIG_BOOT_CONFIG_EMBED
const char * __init xbc_get_embedded_bootconfig(size_t *size);
#else
static inline const char *xbc_get_embedded_bootconfig(size_t *size)
{
	return NULL;
}
#endif

#endif
Commit	Line	Data
76db5a27 MH	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	#ifndef _LINUX_XBC_H
	3	#define _LINUX_XBC_H
	4	/*
	5	* Extra Boot Config
	6	* Copyright (C) 2019 Linaro Ltd.
	7	* Author: Masami Hiramatsu <mhiramat@kernel.org>
	8	*/
	9
4ee1b4ca	10	#ifdef __KERNEL__
76db5a27 MH	11	#include <linux/kernel.h>
76db5a27 MH	12	#include <linux/types.h>
4ee1b4ca MH	13	#else /* !__KERNEL__ */
	14	/*
	15	* NOTE: This is only for tools/bootconfig, because tools/bootconfig will
	16	* run the parser sanity test.
	17	* This does NOT mean linux/bootconfig.h is available in the user space.
	18	* However, if you change this file, please make sure the tools/bootconfig
	19	* has no issue on building and running.
	20	*/
	21	#endif
76db5a27	22
85c46b78 MH	23	#define BOOTCONFIG_MAGIC "#BOOTCONFIG\n"
85c46b78 MH	24	#define BOOTCONFIG_MAGIC_LEN 12
e1cef2d4 MH	25	#define BOOTCONFIG_ALIGN_SHIFT 2
	26	#define BOOTCONFIG_ALIGN (1 << BOOTCONFIG_ALIGN_SHIFT)
	27	#define BOOTCONFIG_ALIGN_MASK (BOOTCONFIG_ALIGN - 1)
85c46b78	28
99f4f5d6 MH	29	/**
	30	* xbc_calc_checksum() - Calculate checksum of bootconfig
	31	* @data: Bootconfig data.
	32	* @size: The size of the bootconfig data.
	33	*
	34	* Calculate the checksum value of the bootconfig data.
	35	* The checksum will be used with the BOOTCONFIG_MAGIC and the size for
	36	* embedding the bootconfig in the initrd image.
	37	*/
4f292c48	38	static inline __init uint32_t xbc_calc_checksum(void *data, uint32_t size)
99f4f5d6 MH	39	{
99f4f5d6 MH	40	unsigned char *p = data;
4f292c48	41	uint32_t ret = 0;
99f4f5d6 MH	42
	43	while (size--)
	44	ret += *p++;
	45
	46	return ret;
	47	}
	48
76db5a27 MH	49	/* XBC tree node */
76db5a27 MH	50	struct xbc_node {
4f292c48 MH	51	uint16_t next;
	52	uint16_t child;
	53	uint16_t parent;
	54	uint16_t data;
76db5a27 MH	55	} __attribute__ ((__packed__));
	56
	57	#define XBC_KEY 0
	58	#define XBC_VALUE (1 << 15)
	59	/* Maximum size of boot config is 32KB - 1 */
	60	#define XBC_DATA_MAX (XBC_VALUE - 1)
	61
6c406249	62	#define XBC_NODE_MAX 8192
76db5a27 MH	63	#define XBC_KEYLEN_MAX 256
	64	#define XBC_DEPTH_MAX 16
	65
	66	/* Node tree access raw APIs */
	67	struct xbc_node * __init xbc_root_node(void);
	68	int __init xbc_node_index(struct xbc_node *node);
	69	struct xbc_node * __init xbc_node_get_parent(struct xbc_node *node);
	70	struct xbc_node * __init xbc_node_get_child(struct xbc_node *node);
	71	struct xbc_node * __init xbc_node_get_next(struct xbc_node *node);
	72	const char * __init xbc_node_get_data(struct xbc_node *node);
	73
	74	/**
	75	* xbc_node_is_value() - Test the node is a value node
	76	* @node: An XBC node.
	77	*
	78	* Test the @node is a value node and return true if a value node, false if not.
	79	*/
	80	static inline __init bool xbc_node_is_value(struct xbc_node *node)
	81	{
	82	return node->data & XBC_VALUE;
	83	}
	84
	85	/**
	86	* xbc_node_is_key() - Test the node is a key node
	87	* @node: An XBC node.
	88	*
	89	* Test the @node is a key node and return true if a key node, false if not.
	90	*/
	91	static inline __init bool xbc_node_is_key(struct xbc_node *node)
	92	{
	93	return !xbc_node_is_value(node);
	94	}
	95
	96	/**
	97	* xbc_node_is_array() - Test the node is an arraied value node
	98	* @node: An XBC node.
	99	*
	100	* Test the @node is an arraied value node.
	101	*/
	102	static inline __init bool xbc_node_is_array(struct xbc_node *node)
	103	{
ca24306d	104	return xbc_node_is_value(node) && node->child != 0;
76db5a27 MH	105	}
	106
	107	/**
	108	* xbc_node_is_leaf() - Test the node is a leaf key node
	109	* @node: An XBC node.
	110	*
	111	* Test the @node is a leaf key node which is a key node and has a value node
	112	* or no child. Returns true if it is a leaf node, or false if not.
e5efaeb8 MH	113	* Note that the leaf node can have subkey nodes in addition to the
e5efaeb8 MH	114	* value node.
76db5a27 MH	115	*/
	116	static inline __init bool xbc_node_is_leaf(struct xbc_node *node)
	117	{
	118	return xbc_node_is_key(node) &&
	119	(!node->child \|\| xbc_node_is_value(xbc_node_get_child(node)));
	120	}
	121
	122	/* Tree-based key-value access APIs */
5dfe50b0	123	struct xbc_node * __init xbc_node_find_subkey(struct xbc_node *parent,
76db5a27 MH	124	const char *key);
	125
	126	const char * __init xbc_node_find_value(struct xbc_node *parent,
	127	const char *key,
	128	struct xbc_node **vnode);
	129
	130	struct xbc_node * __init xbc_node_find_next_leaf(struct xbc_node *root,
	131	struct xbc_node *leaf);
	132
	133	const char * __init xbc_node_find_next_key_value(struct xbc_node *root,
	134	struct xbc_node **leaf);
	135
	136	/**
	137	* xbc_find_value() - Find a value which matches the key
	138	* @key: Search key
	139	* @vnode: A container pointer of XBC value node.
	140	*
	141	* Search a value whose key matches @key from whole of XBC tree and return
	142	* the value if found. Found value node is stored in *@vnode.
	143	* Note that this can return 0-length string and store NULL in *@vnode for
	144	* key-only (non-value) entry.
	145	*/
	146	static inline const char * __init
	147	xbc_find_value(const char key, struct xbc_node *vnode)
	148	{
	149	return xbc_node_find_value(NULL, key, vnode);
	150	}
	151
	152	/**
	153	* xbc_find_node() - Find a node which matches the key
	154	* @key: Search key
	155	*
	156	* Search a (key) node whose key matches @key from whole of XBC tree and
	157	* return the node if found. If not found, returns NULL.
	158	*/
	159	static inline struct xbc_node * __init xbc_find_node(const char *key)
	160	{
5dfe50b0	161	return xbc_node_find_subkey(NULL, key);
76db5a27 MH	162	}
76db5a27 MH	163
e5efaeb8 MH	164	/**
	165	* xbc_node_get_subkey() - Return the first subkey node if exists
	166	* @node: Parent node
	167	*
	168	* Return the first subkey node of the @node. If the @node has no child
	169	* or only value node, this will return NULL.
	170	*/
	171	static inline struct xbc_node * __init xbc_node_get_subkey(struct xbc_node *node)
	172	{
	173	struct xbc_node *child = xbc_node_get_child(node);
	174
	175	if (child && xbc_node_is_value(child))
	176	return xbc_node_get_next(child);
	177	else
	178	return child;
	179	}
	180
76db5a27 MH	181	/**
	182	* xbc_array_for_each_value() - Iterate value nodes on an array
	183	* @anode: An XBC arraied value node
	184	* @value: A value
	185	*
	186	* Iterate array value nodes and values starts from @anode. This is expected to
	187	* be used with xbc_find_value() and xbc_node_find_value(), so that user can
	188	* process each array entry node.
	189	*/
	190	#define xbc_array_for_each_value(anode, value) \
	191	for (value = xbc_node_get_data(anode); anode != NULL ; \
ca24306d	192	anode = xbc_node_get_child(anode), \
76db5a27 MH	193	value = anode ? xbc_node_get_data(anode) : NULL)
	194
	195	/**
	196	* xbc_node_for_each_child() - Iterate child nodes
	197	* @parent: An XBC node.
	198	* @child: Iterated XBC node.
	199	*
	200	* Iterate child nodes of @parent. Each child nodes are stored to @child.
e5efaeb8	201	* The @child can be mixture of a value node and subkey nodes.
76db5a27 MH	202	*/
	203	#define xbc_node_for_each_child(parent, child) \
	204	for (child = xbc_node_get_child(parent); child != NULL ; \
	205	child = xbc_node_get_next(child))
	206
e5efaeb8 MH	207	/**
	208	* xbc_node_for_each_subkey() - Iterate child subkey nodes
	209	* @parent: An XBC node.
	210	* @child: Iterated XBC node.
	211	*
	212	* Iterate subkey nodes of @parent. Each child nodes are stored to @child.
	213	* The @child is only the subkey node.
	214	*/
	215	#define xbc_node_for_each_subkey(parent, child) \
	216	for (child = xbc_node_get_subkey(parent); child != NULL ; \
	217	child = xbc_node_get_next(child))
	218
76db5a27 MH	219	/**
	220	* xbc_node_for_each_array_value() - Iterate array entries of geven key
	221	* @node: An XBC node.
	222	* @key: A key string searched under @node
	223	* @anode: Iterated XBC node of array entry.
	224	* @value: Iterated value of array entry.
	225	*
	226	* Iterate array entries of given @key under @node. Each array entry node
c23c8082	227	* is stored to @anode and @value. If the @node doesn't have @key node,
76db5a27 MH	228	* it does nothing.
76db5a27 MH	229	* Note that even if the found key node has only one value (not array)
c23c8082	230	* this executes block once. However, if the found key node has no value
76db5a27 MH	231	* (key-only node), this does nothing. So don't use this for testing the
	232	* key-value pair existence.
	233	*/
	234	#define xbc_node_for_each_array_value(node, key, anode, value) \
	235	for (value = xbc_node_find_value(node, key, &anode); value != NULL; \
ca24306d	236	anode = xbc_node_get_child(anode), \
76db5a27 MH	237	value = anode ? xbc_node_get_data(anode) : NULL)
	238
	239	/**
	240	* xbc_node_for_each_key_value() - Iterate key-value pairs under a node
	241	* @node: An XBC node.
	242	* @knode: Iterated key node
	243	* @value: Iterated value string
	244	*
	245	* Iterate key-value pairs under @node. Each key node and value string are
	246	* stored in @knode and @value respectively.
	247	*/
	248	#define xbc_node_for_each_key_value(node, knode, value) \
	249	for (knode = NULL, value = xbc_node_find_next_key_value(node, &knode);\
	250	knode != NULL; value = xbc_node_find_next_key_value(node, &knode))
	251
	252	/**
	253	* xbc_for_each_key_value() - Iterate key-value pairs
	254	* @knode: Iterated key node
	255	* @value: Iterated value string
	256	*
	257	* Iterate key-value pairs in whole XBC tree. Each key node and value string
	258	* are stored in @knode and @value respectively.
	259	*/
	260	#define xbc_for_each_key_value(knode, value) \
	261	xbc_node_for_each_key_value(NULL, knode, value)
	262
	263	/* Compose partial key */
	264	int __init xbc_node_compose_key_after(struct xbc_node *root,
	265	struct xbc_node node, char buf, size_t size);
	266
	267	/**
	268	* xbc_node_compose_key() - Compose full key string of the XBC node
	269	* @node: An XBC node.
	270	* @buf: A buffer to store the key.
	271	* @size: The size of the @buf.
	272	*
	273	* Compose the full-length key of the @node into @buf. Returns the total
	274	* length of the key stored in @buf. Or returns -EINVAL if @node is NULL,
	275	* and -ERANGE if the key depth is deeper than max depth.
	276	*/
	277	static inline int __init xbc_node_compose_key(struct xbc_node *node,
	278	char *buf, size_t size)
	279	{
	280	return xbc_node_compose_key_after(NULL, node, buf, size);
	281	}
	282
	283	/* XBC node initializer */
bdac5c2b	284	int __init xbc_init(const char buf, size_t size, const char emsg, int epos);
89b74cac	285
e306220c MH	286	/* XBC node and size information */
e306220c MH	287	int __init xbc_get_info(int node_size, size_t data_size);
76db5a27 MH	288
76db5a27 MH	289	/* XBC cleanup data structures */
115d4d08	290	void __init xbc_exit(void);
76db5a27	291
a2a9d67a MH	292	/* XBC embedded bootconfig data in kernel */
	293	#ifdef CONFIG_BOOT_CONFIG_EMBED
	294	const char * __init xbc_get_embedded_bootconfig(size_t *size);
	295	#else
	296	static inline const char xbc_get_embedded_bootconfig(size_t size)
	297	{
	298	return NULL;
	299	}
	300	#endif
	301
76db5a27	302	#endif