diff options
Diffstat (limited to 'drivers/base/devres.c')
| -rw-r--r-- | drivers/base/devres.c | 310 |
1 files changed, 295 insertions, 15 deletions
diff --git a/drivers/base/devres.c b/drivers/base/devres.c index cf7a0c78805..52302946770 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -50,8 +50,8 @@ static void devres_log(struct device *dev, struct devres_node *node, const char *op) { if (unlikely(log_devres)) - dev_printk(KERN_ERR, dev, "DEVRES %3s %p %s (%lu bytes)\n", - op, node, node->name, (unsigned long)node->size); + dev_err(dev, "DEVRES %3s %p %s (%lu bytes)\n", + op, node, node->name, (unsigned long)node->size); } #else /* CONFIG_DEBUG_DEVRES */ #define set_node_dbginfo(node, n, s) do {} while (0) @@ -91,7 +91,8 @@ static __always_inline struct devres * alloc_dr(dr_release_t release, if (unlikely(!dr)) return NULL; - memset(dr, 0, tot_size); + memset(dr, 0, offsetof(struct devres, data)); + INIT_LIST_HEAD(&dr->node.entry); dr->node.release = release; return dr; @@ -110,7 +111,7 @@ void * __devres_alloc(dr_release_t release, size_t size, gfp_t gfp, { struct devres *dr; - dr = alloc_dr(release, size, gfp); + dr = alloc_dr(release, size, gfp | __GFP_ZERO); if (unlikely(!dr)) return NULL; set_node_dbginfo(&dr->node, name, size); @@ -135,7 +136,7 @@ void * devres_alloc(dr_release_t release, size_t size, gfp_t gfp) { struct devres *dr; - dr = alloc_dr(release, size, gfp); + dr = alloc_dr(release, size, gfp | __GFP_ZERO); if (unlikely(!dr)) return NULL; return dr->data; @@ -144,6 +145,48 @@ EXPORT_SYMBOL_GPL(devres_alloc); #endif /** + * devres_for_each_res - Resource iterator + * @dev: Device to iterate resource from + * @release: Look for resources associated with this release function + * @match: Match function (optional) + * @match_data: Data for the match function + * @fn: Function to be called for each matched resource. + * @data: Data for @fn, the 3rd parameter of @fn + * + * Call @fn for each devres of @dev which is associated with @release + * and for which @match returns 1. + * + * RETURNS: + * void + */ +void devres_for_each_res(struct device *dev, dr_release_t release, + dr_match_t match, void *match_data, + void (*fn)(struct device *, void *, void *), + void *data) +{ + struct devres_node *node; + struct devres_node *tmp; + unsigned long flags; + + if (!fn) + return; + + spin_lock_irqsave(&dev->devres_lock, flags); + list_for_each_entry_safe_reverse(node, tmp, + &dev->devres_head, entry) { + struct devres *dr = container_of(node, struct devres, node); + + if (node->release != release) + continue; + if (match && !match(dev, dr->data, match_data)) + continue; + fn(dev, dr->data, data); + } + spin_unlock_irqrestore(&dev->devres_lock, flags); +} +EXPORT_SYMBOL_GPL(devres_for_each_res); + +/** * devres_free - Free device resource data * @res: Pointer to devres data to free * @@ -309,6 +352,10 @@ EXPORT_SYMBOL_GPL(devres_remove); * which @match returns 1. If @match is NULL, it's considered to * match all. If found, the resource is removed atomically and freed. * + * Note that the release function for the resource will not be called, + * only the devres-allocated data will be freed. The caller becomes + * responsible for freeing any other data. + * * RETURNS: * 0 if devres is found and freed, -ENOENT if not found. */ @@ -326,6 +373,37 @@ int devres_destroy(struct device *dev, dr_release_t release, } EXPORT_SYMBOL_GPL(devres_destroy); + +/** + * devres_release - Find a device resource and destroy it, calling release + * @dev: Device to find resource from + * @release: Look for resources associated with this release function + * @match: Match function (optional) + * @match_data: Data for the match function + * + * Find the latest devres of @dev associated with @release and for + * which @match returns 1. If @match is NULL, it's considered to + * match all. If found, the resource is removed atomically, the + * release function called and the resource freed. + * + * RETURNS: + * 0 if devres is found and freed, -ENOENT if not found. + */ +int devres_release(struct device *dev, dr_release_t release, + dr_match_t match, void *match_data) +{ + void *res; + + res = devres_remove(dev, release, match, match_data); + if (unlikely(!res)) + return -ENOENT; + + (*release)(dev, res); + devres_free(res); + return 0; +} +EXPORT_SYMBOL_GPL(devres_release); + static int remove_nodes(struct device *dev, struct list_head *first, struct list_head *end, struct list_head *todo) @@ -397,6 +475,7 @@ static int remove_nodes(struct device *dev, static int release_nodes(struct device *dev, struct list_head *first, struct list_head *end, unsigned long flags) + __releases(&dev->devres_lock) { LIST_HEAD(todo); int cnt; @@ -593,58 +672,259 @@ int devres_release_group(struct device *dev, void *id) EXPORT_SYMBOL_GPL(devres_release_group); /* - * Managed kzalloc/kfree + * Custom devres actions allow inserting a simple function call + * into the teadown sequence. + */ + +struct action_devres { + void *data; + void (*action)(void *); +}; + +static int devm_action_match(struct device *dev, void *res, void *p) +{ + struct action_devres *devres = res; + struct action_devres *target = p; + + return devres->action == target->action && + devres->data == target->data; +} + +static void devm_action_release(struct device *dev, void *res) +{ + struct action_devres *devres = res; + + devres->action(devres->data); +} + +/** + * devm_add_action() - add a custom action to list of managed resources + * @dev: Device that owns the action + * @action: Function that should be called + * @data: Pointer to data passed to @action implementation + * + * This adds a custom action to the list of managed resources so that + * it gets executed as part of standard resource unwinding. + */ +int devm_add_action(struct device *dev, void (*action)(void *), void *data) +{ + struct action_devres *devres; + + devres = devres_alloc(devm_action_release, + sizeof(struct action_devres), GFP_KERNEL); + if (!devres) + return -ENOMEM; + + devres->data = data; + devres->action = action; + + devres_add(dev, devres); + return 0; +} +EXPORT_SYMBOL_GPL(devm_add_action); + +/** + * devm_remove_action() - removes previously added custom action + * @dev: Device that owns the action + * @action: Function implementing the action + * @data: Pointer to data passed to @action implementation + * + * Removes instance of @action previously added by devm_add_action(). + * Both action and data should match one of the existing entries. + */ +void devm_remove_action(struct device *dev, void (*action)(void *), void *data) +{ + struct action_devres devres = { + .data = data, + .action = action, + }; + + WARN_ON(devres_destroy(dev, devm_action_release, devm_action_match, + &devres)); + +} +EXPORT_SYMBOL_GPL(devm_remove_action); + +/* + * Managed kmalloc/kfree */ -static void devm_kzalloc_release(struct device *dev, void *res) +static void devm_kmalloc_release(struct device *dev, void *res) { /* noop */ } -static int devm_kzalloc_match(struct device *dev, void *res, void *data) +static int devm_kmalloc_match(struct device *dev, void *res, void *data) { return res == data; } /** - * devm_kzalloc - Resource-managed kzalloc + * devm_kmalloc - Resource-managed kmalloc * @dev: Device to allocate memory for * @size: Allocation size * @gfp: Allocation gfp flags * - * Managed kzalloc. Memory allocated with this function is + * Managed kmalloc. Memory allocated with this function is * automatically freed on driver detach. Like all other devres * resources, guaranteed alignment is unsigned long long. * * RETURNS: * Pointer to allocated memory on success, NULL on failure. */ -void * devm_kzalloc(struct device *dev, size_t size, gfp_t gfp) +void * devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) { struct devres *dr; /* use raw alloc_dr for kmalloc caller tracing */ - dr = alloc_dr(devm_kzalloc_release, size, gfp); + dr = alloc_dr(devm_kmalloc_release, size, gfp); if (unlikely(!dr)) return NULL; + /* + * This is named devm_kzalloc_release for historical reasons + * The initial implementation did not support kmalloc, only kzalloc + */ set_node_dbginfo(&dr->node, "devm_kzalloc_release", size); devres_add(dev, dr->data); return dr->data; } -EXPORT_SYMBOL_GPL(devm_kzalloc); +EXPORT_SYMBOL_GPL(devm_kmalloc); + +/** + * devm_kstrdup - Allocate resource managed space and + * copy an existing string into that. + * @dev: Device to allocate memory for + * @s: the string to duplicate + * @gfp: the GFP mask used in the devm_kmalloc() call when + * allocating memory + * RETURNS: + * Pointer to allocated string on success, NULL on failure. + */ +char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) +{ + size_t size; + char *buf; + + if (!s) + return NULL; + + size = strlen(s) + 1; + buf = devm_kmalloc(dev, size, gfp); + if (buf) + memcpy(buf, s, size); + return buf; +} +EXPORT_SYMBOL_GPL(devm_kstrdup); /** * devm_kfree - Resource-managed kfree * @dev: Device this memory belongs to * @p: Memory to free * - * Free memory allocated with dev_kzalloc(). + * Free memory allocated with devm_kmalloc(). */ void devm_kfree(struct device *dev, void *p) { int rc; - rc = devres_destroy(dev, devm_kzalloc_release, devm_kzalloc_match, p); + rc = devres_destroy(dev, devm_kmalloc_release, devm_kmalloc_match, p); WARN_ON(rc); } EXPORT_SYMBOL_GPL(devm_kfree); + +/** + * devm_kmemdup - Resource-managed kmemdup + * @dev: Device this memory belongs to + * @src: Memory region to duplicate + * @len: Memory region length + * @gfp: GFP mask to use + * + * Duplicate region of a memory using resource managed kmalloc + */ +void *devm_kmemdup(struct device *dev, const void *src, size_t len, gfp_t gfp) +{ + void *p; + + p = devm_kmalloc(dev, len, gfp); + if (p) + memcpy(p, src, len); + + return p; +} +EXPORT_SYMBOL_GPL(devm_kmemdup); + +struct pages_devres { + unsigned long addr; + unsigned int order; +}; + +static int devm_pages_match(struct device *dev, void *res, void *p) +{ + struct pages_devres *devres = res; + struct pages_devres *target = p; + + return devres->addr == target->addr; +} + +static void devm_pages_release(struct device *dev, void *res) +{ + struct pages_devres *devres = res; + + free_pages(devres->addr, devres->order); +} + +/** + * devm_get_free_pages - Resource-managed __get_free_pages + * @dev: Device to allocate memory for + * @gfp_mask: Allocation gfp flags + * @order: Allocation size is (1 << order) pages + * + * Managed get_free_pages. Memory allocated with this function is + * automatically freed on driver detach. + * + * RETURNS: + * Address of allocated memory on success, 0 on failure. + */ + +unsigned long devm_get_free_pages(struct device *dev, + gfp_t gfp_mask, unsigned int order) +{ + struct pages_devres *devres; + unsigned long addr; + + addr = __get_free_pages(gfp_mask, order); + + if (unlikely(!addr)) + return 0; + + devres = devres_alloc(devm_pages_release, + sizeof(struct pages_devres), GFP_KERNEL); + if (unlikely(!devres)) { + free_pages(addr, order); + return 0; + } + + devres->addr = addr; + devres->order = order; + + devres_add(dev, devres); + return addr; +} +EXPORT_SYMBOL_GPL(devm_get_free_pages); + +/** + * devm_free_pages - Resource-managed free_pages + * @dev: Device this memory belongs to + * @addr: Memory to free + * + * Free memory allocated with devm_get_free_pages(). Unlike free_pages, + * there is no need to supply the @order. + */ +void devm_free_pages(struct device *dev, unsigned long addr) +{ + struct pages_devres devres = { .addr = addr }; + + WARN_ON(devres_release(dev, devm_pages_release, devm_pages_match, + &devres)); +} +EXPORT_SYMBOL_GPL(devm_free_pages); |
