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-rw-r--r--drivers/thunderbolt/property.c670
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);