diff options
Diffstat (limited to 'drivers/thunderbolt/property.c')
| -rw-r--r-- | drivers/thunderbolt/property.c | 670 |
1 files changed, 670 insertions, 0 deletions
diff --git a/drivers/thunderbolt/property.c b/drivers/thunderbolt/property.c new file mode 100644 index 000000000000..8fe913a95b4a --- /dev/null +++ b/drivers/thunderbolt/property.c @@ -0,0 +1,670 @@ +/* + * Thunderbolt XDomain property support + * + * Copyright (C) 2017, Intel Corporation + * Authors: Michael Jamet <michael.jamet@intel.com> + * Mika Westerberg <mika.westerberg@linux.intel.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/err.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/uuid.h> +#include <linux/thunderbolt.h> + +struct tb_property_entry { + u32 key_hi; + u32 key_lo; + u16 length; + u8 reserved; + u8 type; + u32 value; +}; + +struct tb_property_rootdir_entry { + u32 magic; + u32 length; + struct tb_property_entry entries[]; +}; + +struct tb_property_dir_entry { + u32 uuid[4]; + struct tb_property_entry entries[]; +}; + +#define TB_PROPERTY_ROOTDIR_MAGIC 0x55584401 + +static struct tb_property_dir *__tb_property_parse_dir(const u32 *block, + size_t block_len, unsigned int dir_offset, size_t dir_len, + bool is_root); + +static inline void parse_dwdata(void *dst, const void *src, size_t dwords) +{ + be32_to_cpu_array(dst, src, dwords); +} + +static inline void format_dwdata(void *dst, const void *src, size_t dwords) +{ + cpu_to_be32_array(dst, src, dwords); +} + +static bool tb_property_entry_valid(const struct tb_property_entry *entry, + size_t block_len) +{ + switch (entry->type) { + case TB_PROPERTY_TYPE_DIRECTORY: + case TB_PROPERTY_TYPE_DATA: + case TB_PROPERTY_TYPE_TEXT: + if (entry->length > block_len) + return false; + if (entry->value + entry->length > block_len) + return false; + break; + + case TB_PROPERTY_TYPE_VALUE: + if (entry->length != 1) + return false; + break; + } + + return true; +} + +static bool tb_property_key_valid(const char *key) +{ + return key && strlen(key) <= TB_PROPERTY_KEY_SIZE; +} + +static struct tb_property * +tb_property_alloc(const char *key, enum tb_property_type type) +{ + struct tb_property *property; + + property = kzalloc(sizeof(*property), GFP_KERNEL); + if (!property) + return NULL; + + strcpy(property->key, key); + property->type = type; + INIT_LIST_HEAD(&property->list); + + return property; +} + +static struct tb_property *tb_property_parse(const u32 *block, size_t block_len, + const struct tb_property_entry *entry) +{ + char key[TB_PROPERTY_KEY_SIZE + 1]; + struct tb_property *property; + struct tb_property_dir *dir; + + if (!tb_property_entry_valid(entry, block_len)) + return NULL; + + parse_dwdata(key, entry, 2); + key[TB_PROPERTY_KEY_SIZE] = '\0'; + + property = tb_property_alloc(key, entry->type); + if (!property) + return NULL; + + property->length = entry->length; + + switch (property->type) { + case TB_PROPERTY_TYPE_DIRECTORY: + dir = __tb_property_parse_dir(block, block_len, entry->value, + entry->length, false); + if (!dir) { + kfree(property); + return NULL; + } + property->value.dir = dir; + break; + + case TB_PROPERTY_TYPE_DATA: + property->value.data = kcalloc(property->length, sizeof(u32), + GFP_KERNEL); + if (!property->value.data) { + kfree(property); + return NULL; + } + parse_dwdata(property->value.data, block + entry->value, + entry->length); + break; + + case TB_PROPERTY_TYPE_TEXT: + property->value.text = kcalloc(property->length, sizeof(u32), + GFP_KERNEL); + if (!property->value.text) { + kfree(property); + return NULL; + } + parse_dwdata(property->value.text, block + entry->value, + entry->length); + /* Force null termination */ + property->value.text[property->length * 4 - 1] = '\0'; + break; + + case TB_PROPERTY_TYPE_VALUE: + property->value.immediate = entry->value; + break; + + default: + property->type = TB_PROPERTY_TYPE_UNKNOWN; + break; + } + + return property; +} + +static struct tb_property_dir *__tb_property_parse_dir(const u32 *block, + size_t block_len, unsigned int dir_offset, size_t dir_len, bool is_root) +{ + const struct tb_property_entry *entries; + size_t i, content_len, nentries; + unsigned int content_offset; + struct tb_property_dir *dir; + + dir = kzalloc(sizeof(*dir), GFP_KERNEL); + if (!dir) + return NULL; + + if (is_root) { + content_offset = dir_offset + 2; + content_len = dir_len; + } else { + dir->uuid = kmemdup(&block[dir_offset], sizeof(*dir->uuid), + GFP_KERNEL); + content_offset = dir_offset + 4; + content_len = dir_len - 4; /* Length includes UUID */ + } + + entries = (const struct tb_property_entry *)&block[content_offset]; + nentries = content_len / (sizeof(*entries) / 4); + + INIT_LIST_HEAD(&dir->properties); + + for (i = 0; i < nentries; i++) { + struct tb_property *property; + + property = tb_property_parse(block, block_len, &entries[i]); + if (!property) { + tb_property_free_dir(dir); + return NULL; + } + + list_add_tail(&property->list, &dir->properties); + } + + return dir; +} + +/** + * tb_property_parse_dir() - Parses properties from given property block + * @block: Property block to parse + * @block_len: Number of dword elements in the property block + * + * This function parses the XDomain properties data block into format that + * can be traversed using the helper functions provided by this module. + * Upon success returns the parsed directory. In case of error returns + * %NULL. The resulting &struct tb_property_dir needs to be released by + * calling tb_property_free_dir() when not needed anymore. + * + * The @block is expected to be root directory. + */ +struct tb_property_dir *tb_property_parse_dir(const u32 *block, + size_t block_len) +{ + const struct tb_property_rootdir_entry *rootdir = + (const struct tb_property_rootdir_entry *)block; + + if (rootdir->magic != TB_PROPERTY_ROOTDIR_MAGIC) + return NULL; + if (rootdir->length > block_len) + return NULL; + + return __tb_property_parse_dir(block, block_len, 0, rootdir->length, + true); +} + +/** + * tb_property_create_dir() - Creates new property directory + * @uuid: UUID used to identify the particular directory + * + * Creates new, empty property directory. If @uuid is %NULL then the + * directory is assumed to be root directory. + */ +struct tb_property_dir *tb_property_create_dir(const uuid_t *uuid) +{ + struct tb_property_dir *dir; + + dir = kzalloc(sizeof(*dir), GFP_KERNEL); + if (!dir) + return NULL; + + INIT_LIST_HEAD(&dir->properties); + if (uuid) { + dir->uuid = kmemdup(uuid, sizeof(*dir->uuid), GFP_KERNEL); + if (!dir->uuid) { + kfree(dir); + return NULL; + } + } + + return dir; +} +EXPORT_SYMBOL_GPL(tb_property_create_dir); + +static void tb_property_free(struct tb_property *property) +{ + switch (property->type) { + case TB_PROPERTY_TYPE_DIRECTORY: + tb_property_free_dir(property->value.dir); + break; + + case TB_PROPERTY_TYPE_DATA: + kfree(property->value.data); + break; + + case TB_PROPERTY_TYPE_TEXT: + kfree(property->value.text); + break; + + default: + break; + } + + kfree(property); +} + +/** + * tb_property_free_dir() - Release memory allocated for property directory + * @dir: Directory to release + * + * This will release all the memory the directory occupies including all + * descendants. It is OK to pass %NULL @dir, then the function does + * nothing. + */ +void tb_property_free_dir(struct tb_property_dir *dir) +{ + struct tb_property *property, *tmp; + + if (!dir) + return; + + list_for_each_entry_safe(property, tmp, &dir->properties, list) { + list_del(&property->list); + tb_property_free(property); + } + kfree(dir->uuid); + kfree(dir); +} +EXPORT_SYMBOL_GPL(tb_property_free_dir); + +static size_t tb_property_dir_length(const struct tb_property_dir *dir, + bool recurse, size_t *data_len) +{ + const struct tb_property *property; + size_t len = 0; + + if (dir->uuid) + len += sizeof(*dir->uuid) / 4; + else + len += sizeof(struct tb_property_rootdir_entry) / 4; + + list_for_each_entry(property, &dir->properties, list) { + len += sizeof(struct tb_property_entry) / 4; + + switch (property->type) { + case TB_PROPERTY_TYPE_DIRECTORY: + if (recurse) { + len += tb_property_dir_length( + property->value.dir, recurse, data_len); + } + /* Reserve dword padding after each directory */ + if (data_len) + *data_len += 1; + break; + + case TB_PROPERTY_TYPE_DATA: + case TB_PROPERTY_TYPE_TEXT: + if (data_len) + *data_len += property->length; + break; + + default: + break; + } + } + + return len; +} + +static ssize_t __tb_property_format_dir(const struct tb_property_dir *dir, + u32 *block, unsigned int start_offset, size_t block_len) +{ + unsigned int data_offset, dir_end; + const struct tb_property *property; + struct tb_property_entry *entry; + size_t dir_len, data_len = 0; + int ret; + + /* + * The structure of property block looks like following. Leaf + * data/text is included right after the directory and each + * directory follows each other (even nested ones). + * + * +----------+ <-- start_offset + * | header | <-- root directory header + * +----------+ --- + * | entry 0 | -^--------------------. + * +----------+ | | + * | entry 1 | -|--------------------|--. + * +----------+ | | | + * | entry 2 | -|-----------------. | | + * +----------+ | | | | + * : : | dir_len | | | + * . . | | | | + * : : | | | | + * +----------+ | | | | + * | entry n | v | | | + * +----------+ <-- data_offset | | | + * | data 0 | <------------------|--' | + * +----------+ | | + * | data 1 | <------------------|-----' + * +----------+ | + * | 00000000 | padding | + * +----------+ <-- dir_end <------' + * | UUID | <-- directory UUID (child directory) + * +----------+ + * | entry 0 | + * +----------+ + * | entry 1 | + * +----------+ + * : : + * . . + * : : + * +----------+ + * | entry n | + * +----------+ + * | data 0 | + * +----------+ + * + * We use dir_end to hold pointer to the end of the directory. It + * will increase as we add directories and each directory should be + * added starting from previous dir_end. + */ + dir_len = tb_property_dir_length(dir, false, &data_len); + data_offset = start_offset + dir_len; + dir_end = start_offset + data_len + dir_len; + + if (data_offset > dir_end) + return -EINVAL; + if (dir_end > block_len) + return -EINVAL; + + /* Write headers first */ + if (dir->uuid) { + struct tb_property_dir_entry *pe; + + pe = (struct tb_property_dir_entry *)&block[start_offset]; + memcpy(pe->uuid, dir->uuid, sizeof(pe->uuid)); + entry = pe->entries; + } else { + struct tb_property_rootdir_entry *re; + + re = (struct tb_property_rootdir_entry *)&block[start_offset]; + re->magic = TB_PROPERTY_ROOTDIR_MAGIC; + re->length = dir_len - sizeof(*re) / 4; + entry = re->entries; + } + + list_for_each_entry(property, &dir->properties, list) { + const struct tb_property_dir *child; + + format_dwdata(entry, property->key, 2); + entry->type = property->type; + + switch (property->type) { + case TB_PROPERTY_TYPE_DIRECTORY: + child = property->value.dir; + ret = __tb_property_format_dir(child, block, dir_end, + block_len); + if (ret < 0) + return ret; + entry->length = tb_property_dir_length(child, false, + NULL); + entry->value = dir_end; + dir_end = ret; + break; + + case TB_PROPERTY_TYPE_DATA: + format_dwdata(&block[data_offset], property->value.data, + property->length); + entry->length = property->length; + entry->value = data_offset; + data_offset += entry->length; + break; + + case TB_PROPERTY_TYPE_TEXT: + format_dwdata(&block[data_offset], property->value.text, + property->length); + entry->length = property->length; + entry->value = data_offset; + data_offset += entry->length; + break; + + case TB_PROPERTY_TYPE_VALUE: + entry->length = property->length; + entry->value = property->value.immediate; + break; + + default: + break; + } + + entry++; + } + + return dir_end; +} + +/** + * tb_property_format_dir() - Formats directory to the packed XDomain format + * @dir: Directory to format + * @block: Property block where the packed data is placed + * @block_len: Length of the property block + * + * This function formats the directory to the packed format that can be + * then send over the thunderbolt fabric to receiving host. Returns %0 in + * case of success and negative errno on faulure. Passing %NULL in @block + * returns number of entries the block takes. + */ +ssize_t tb_property_format_dir(const struct tb_property_dir *dir, u32 *block, + size_t block_len) +{ + ssize_t ret; + + if (!block) { + size_t dir_len, data_len = 0; + + dir_len = tb_property_dir_length(dir, true, &data_len); + return dir_len + data_len; + } + + ret = __tb_property_format_dir(dir, block, 0, block_len); + return ret < 0 ? ret : 0; +} + +/** + * tb_property_add_immediate() - Add immediate property to directory + * @parent: Directory to add the property + * @key: Key for the property + * @value: Immediate value to store with the property + */ +int tb_property_add_immediate(struct tb_property_dir *parent, const char *key, + u32 value) +{ + struct tb_property *property; + + if (!tb_property_key_valid(key)) + return -EINVAL; + + property = tb_property_alloc(key, TB_PROPERTY_TYPE_VALUE); + if (!property) + return -ENOMEM; + + property->length = 1; + property->value.immediate = value; + + list_add_tail(&property->list, &parent->properties); + return 0; +} +EXPORT_SYMBOL_GPL(tb_property_add_immediate); + +/** + * tb_property_add_data() - Adds arbitrary data property to directory + * @parent: Directory to add the property + * @key: Key for the property + * @buf: Data buffer to add + * @buflen: Number of bytes in the data buffer + * + * Function takes a copy of @buf and adds it to the directory. + */ +int tb_property_add_data(struct tb_property_dir *parent, const char *key, + const void *buf, size_t buflen) +{ + /* Need to pad to dword boundary */ + size_t size = round_up(buflen, 4); + struct tb_property *property; + + if (!tb_property_key_valid(key)) + return -EINVAL; + + property = tb_property_alloc(key, TB_PROPERTY_TYPE_DATA); + if (!property) + return -ENOMEM; + + property->length = size / 4; + property->value.data = kzalloc(size, GFP_KERNEL); + memcpy(property->value.data, buf, buflen); + + list_add_tail(&property->list, &parent->properties); + return 0; +} +EXPORT_SYMBOL_GPL(tb_property_add_data); + +/** + * tb_property_add_text() - Adds string property to directory + * @parent: Directory to add the property + * @key: Key for the property + * @text: String to add + * + * Function takes a copy of @text and adds it to the directory. + */ +int tb_property_add_text(struct tb_property_dir *parent, const char *key, + const char *text) +{ + /* Need to pad to dword boundary */ + size_t size = round_up(strlen(text) + 1, 4); + struct tb_property *property; + + if (!tb_property_key_valid(key)) + return -EINVAL; + + property = tb_property_alloc(key, TB_PROPERTY_TYPE_TEXT); + if (!property) + return -ENOMEM; + + property->length = size / 4; + property->value.data = kzalloc(size, GFP_KERNEL); + strcpy(property->value.text, text); + + list_add_tail(&property->list, &parent->properties); + return 0; +} +EXPORT_SYMBOL_GPL(tb_property_add_text); + +/** + * tb_property_add_dir() - Adds a directory to the parent directory + * @parent: Directory to add the property + * @key: Key for the property + * @dir: Directory to add + */ +int tb_property_add_dir(struct tb_property_dir *parent, const char *key, + struct tb_property_dir *dir) +{ + struct tb_property *property; + + if (!tb_property_key_valid(key)) + return -EINVAL; + + property = tb_property_alloc(key, TB_PROPERTY_TYPE_DIRECTORY); + if (!property) + return -ENOMEM; + + property->value.dir = dir; + + list_add_tail(&property->list, &parent->properties); + return 0; +} +EXPORT_SYMBOL_GPL(tb_property_add_dir); + +/** + * tb_property_remove() - Removes property from a parent directory + * @property: Property to remove + * + * Note memory for @property is released as well so it is not allowed to + * touch the object after call to this function. + */ +void tb_property_remove(struct tb_property *property) +{ + list_del(&property->list); + kfree(property); +} +EXPORT_SYMBOL_GPL(tb_property_remove); + +/** + * tb_property_find() - Find a property from a directory + * @dir: Directory where the property is searched + * @key: Key to look for + * @type: Type of the property + * + * Finds and returns property from the given directory. Does not recurse + * into sub-directories. Returns %NULL if the property was not found. + */ +struct tb_property *tb_property_find(struct tb_property_dir *dir, + const char *key, enum tb_property_type type) +{ + struct tb_property *property; + + list_for_each_entry(property, &dir->properties, list) { + if (property->type == type && !strcmp(property->key, key)) + return property; + } + + return NULL; +} +EXPORT_SYMBOL_GPL(tb_property_find); + +/** + * tb_property_get_next() - Get next property from directory + * @dir: Directory holding properties + * @prev: Previous property in the directory (%NULL returns the first) + */ +struct tb_property *tb_property_get_next(struct tb_property_dir *dir, + struct tb_property *prev) +{ + if (prev) { + if (list_is_last(&prev->list, &dir->properties)) + return NULL; + return list_next_entry(prev, list); + } + return list_first_entry_or_null(&dir->properties, struct tb_property, + list); +} +EXPORT_SYMBOL_GPL(tb_property_get_next); |