diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-30 09:22:00 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-30 09:22:00 -0700 |
| commit | 034dd340b08be1f2f0477ad16131d609f9dbd53c (patch) | |
| tree | 2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /drivers/thunderbolt/property.c | |
| download | linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip | |
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt:
- Fix error output of boot instance creation failure
Currently if a boot instance creation fails, instead of printing out
the name of the instance that failed, it prints "(null)". That is
because it prints "cur_str" that had already been processed by
strsep(). Print the saved name instead.
While at it, print the error code of the failure.
- Fix use-after-free for same named historgrams
Histograms can be named so that they can be used in multiple events.
But if the named histogram has a variable attached, the second event
that uses the named histogram which duplicates it and needs to free
the original after duplication leaves the old variable in place and
still visible. If another histogram uses than variable, it will use
the stale one which will try to reference the freed duplicate
histogram and crash the kernel.
Free the duplicate variables along with the duplicated histogram
data.
- Check return value of kthread_run() in event self test
The events self tests uses a kthread for testing but does not check
if it succeeded in creating a kthread. If the kthread creation were
to fail, the code will still try to call kthread_stop() on the error
returned.
- Fix race between reading trace_pipe and updating subbuffer size
If a user is reading the trace_pipe file at the same time they update
the ring buffer sub-buffer size, can cause the trace_pipe read to
read stale data. Add trace_access_lock() around updating the ring
buffer sub-buffer size.
- Fix eventfs_inode on failure path in creation of the events directory
In the creation of the "events" directory, if after allocating the
eventfs_inode a failure is detected, it calls cleanup_ei() which
calls free_ei(). The free_ei() will test if eventfs_inode being freed
has no children. It is a bug if it does. But on the failure case of
the creation of the "events" directory, the children lists have not
yet been initialized and the free will trigger a warning because
list_empty() on an uninitialized list returns false.
Move the initialization into init_ei() where it makes more sense and
makes sure that a created eventfs_inode has its lists initialized
upon creation.
- Check return value of kthread_run() in ftrace direct sample code
The sample code that shows how to use the ftrace direct calls does
not test the return of kthread_run() to see if it succeeds. Return a
failure if the kthread_run() doesn't succeed.
- Clear user events state on fork in case of alloc failure
On fork, the child gets a pointer to the parent's user events state.
It makes a copy of it then updates the child's pointer to it. But if
the allocation fails, the duplication function leaves the child with
a pointer to its parent's descriptor. When the child cleans up its
data, it will free the parent's descriptor while the parent is still
using it.
In the duplication function, set the child's user_event_mm to NULL
before testing if the allocation succeeded, and when it exits it will
not free the parent's descriptor.
- Fix retry exhaustion in simple ring buffer reader swap
simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
post-decrements it only after a failed link replacement. On the final
attempt, a successful replacement leaves retry at zero, while a
failed replacement leaves it at -1.
But the check for success expects the retry value to be non-zero and
exits with an error on zero. This is the opposite result. Fix it.
- Fail nicely when the remote swap_reader_page() returns an error
Currently, if the swap_reader_page() of a remote buffer fails, it
triggers a WARN_ON_ONCE() and continues normally. Instead, have it
exit with an error and a pr_warn() print instead of a full WARNING.
* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Stop remote reader update when page swap fails
tracing: Fix retry exhaustion in simple ring buffer reader swap
tracing/user_events: Clear copied tracing state before fork duplication
samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
eventfs: Initialize ei->children and ei->list in init_ei()
tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
tracing: Fix crash passing ERR_PTR to kthread_stop()
tracing: Fix use-after-free with same-name named triggers
tracing: Fix logged instance name on creation failure
Diffstat (limited to 'drivers/thunderbolt/property.c')
| -rw-r--r-- | drivers/thunderbolt/property.c | 858 |
1 files changed, 858 insertions, 0 deletions
diff --git a/drivers/thunderbolt/property.c b/drivers/thunderbolt/property.c new file mode 100644 index 000000000..df18a6d69 --- /dev/null +++ b/drivers/thunderbolt/property.c @@ -0,0 +1,858 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Thunderbolt XDomain property support + * + * Copyright (C) 2017, Intel Corporation + * Authors: Michael Jamet <michael.jamet@intel.com> + * Mika Westerberg <mika.westerberg@linux.intel.com> + */ + +#include <linux/err.h> +#include <linux/overflow.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 +#define TB_PROPERTY_MAX_DEPTH 8 + +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, unsigned int depth); +static struct tb_property *tb_property_copy(const struct tb_property *property); + +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) +{ + u32 end; + + switch (entry->type) { + case TB_PROPERTY_TYPE_DIRECTORY: + case TB_PROPERTY_TYPE_DATA: + case TB_PROPERTY_TYPE_TEXT: + if (!entry->length) + return false; + if (entry->length > block_len) + return false; + if (check_add_overflow(entry->value, entry->length, &end) || + end > 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_obj(*property); + 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, + unsigned int depth) +{ + 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, depth + 1); + 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, + unsigned int depth) +{ + const struct tb_property_entry *entries; + size_t i, content_len, nentries; + unsigned int content_offset; + struct tb_property_dir *dir; + + if (depth > TB_PROPERTY_MAX_DEPTH) + return NULL; + + dir = kzalloc_obj(*dir); + if (!dir) + return NULL; + + INIT_LIST_HEAD(&dir->properties); + + if (is_root) { + content_offset = dir_offset + 2; + content_len = dir_len; + if (content_offset + content_len > block_len) { + tb_property_free_dir(dir); + return NULL; + } + } else { + if (dir_len < 4) { + tb_property_free_dir(dir); + return NULL; + } + dir->uuid = kmemdup(&block[dir_offset], sizeof(*dir->uuid), + GFP_KERNEL); + if (!dir->uuid) { + tb_property_free_dir(dir); + return NULL; + } + 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); + + for (i = 0; i < nentries; i++) { + struct tb_property *property; + + property = tb_property_parse(block, block_len, &entries[i], depth); + 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. + * + * 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. + * + * Return: Pointer to &struct tb_property_dir, %NULL in case of failure. + */ +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, 0); +} + +/** + * 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. + * + * Return: Pointer to &struct tb_property_dir, %NULL in case of failure. + */ +struct tb_property_dir *tb_property_create_dir(const uuid_t *uuid) +{ + struct tb_property_dir *dir; + + dir = kzalloc_obj(*dir); + 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 sent over the thunderbolt fabric to receiving host. + * + * Passing %NULL in @block returns number of entries the block takes. + * + * Return: %0 on success, negative errno otherwise. + */ +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; +} + +static struct tb_property_dir *copy_dir(const struct tb_property_dir *dir) +{ + struct tb_property *property, *p; + struct tb_property_dir *d; + + if (!dir) + return NULL; + + d = tb_property_create_dir(dir->uuid); + if (!d) + return NULL; + + list_for_each_entry(property, &dir->properties, list) { + p = tb_property_copy(property); + if (!p) + goto err_free; + list_add_tail(&p->list, &d->properties); + } + + return d; + +err_free: + tb_property_free_dir(d); + return NULL; +} + +static struct tb_property *tb_property_copy(const struct tb_property *property) +{ + struct tb_property *p; + + p = tb_property_alloc(property->key, property->type); + if (!p) + return NULL; + + p->length = property->length; + switch (property->type) { + case TB_PROPERTY_TYPE_DIRECTORY: + p->value.dir = copy_dir(property->value.dir); + if (!p->value.dir) + goto err_free; + break; + + case TB_PROPERTY_TYPE_DATA: + p->value.data = kmemdup(property->value.data, + property->length * 4, + GFP_KERNEL); + if (!p->value.data) + goto err_free; + break; + + case TB_PROPERTY_TYPE_TEXT: + p->value.text = kzalloc(p->length * 4, GFP_KERNEL); + if (!p->value.text) + goto err_free; + strcpy(p->value.text, property->value.text); + break; + + case TB_PROPERTY_TYPE_VALUE: + p->value.immediate = property->value.immediate; + break; + + default: + break; + } + + return p; + +err_free: + kfree(p); + return NULL; +} + +/** + * tb_property_copy_dir() - Take a deep copy of directory + * @dir: Directory to copy + * + * The resulting directory needs to be released by calling tb_property_free_dir(). + * + * Return: Pointer to &struct tb_property_dir, %NULL in case of failure. + */ +struct tb_property_dir *tb_property_copy_dir(const struct tb_property_dir *dir) +{ + return copy_dir(dir); +} +EXPORT_SYMBOL_GPL(tb_property_copy_dir); + +/** + * tb_property_merge_dir() - Merges directory into parent + * @parent: Directory to merge @dir + * @dir: Directory that is merged + * @replace: Replace existing entries + * + * This will merge @dir into @parent. Both must have same UUID. The + * properties in @dir will overwrite overlapping properties in @parent + * if @replace is %true. Contents of @dir is copied (so if it is not + * needed afterwards it needs to relesed by calling tb_property_free_dir()). + */ +int tb_property_merge_dir(struct tb_property_dir *parent, + const struct tb_property_dir *dir, + bool replace) +{ + const struct tb_property *property; + + if (WARN_ON(parent == dir)) + return -EINVAL; + + if (!uuid_equal(parent->uuid, dir->uuid)) + return -EINVAL; + + list_for_each_entry(property, &dir->properties, list) { + struct tb_property *p, *tmp; + + tmp = tb_property_copy(property); + if (!tmp) + return -ENOMEM; + + p = tb_property_find(parent, property->key, property->type); + if (p) { + if (replace) { + /* + * Found existing property in parent so + * replace with the new one. + */ + list_replace(&p->list, &tmp->list); + tb_property_free(p); + } else { + tb_property_free(tmp); + continue; + } + } else { + list_add_tail(&tmp->list, &parent->properties); + } + } + + return 0; +} +EXPORT_SYMBOL_GPL(tb_property_merge_dir); + +/** + * 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 + * + * Return: %0 on success, negative errno otherwise. + */ +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. + * + * Return: %0 on success, negative errno otherwise. + */ +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); + if (!property->value.data) { + kfree(property); + return -ENOMEM; + } + + 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. + * + * Return: %0 on success, negative errno otherwise. + */ +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.text = kzalloc(size, GFP_KERNEL); + if (!property->value.text) { + kfree(property); + return -ENOMEM; + } + + 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 + * + * Return: %0 on success, negative errno otherwise. + */ +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. + * + * Return: Pointer to &struct tb_property, %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) + * + * Return: Pointer to &struct tb_property, %NULL if property was not found. + */ +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); |
