| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * drivers/base/devres.c - device resource management |
| * |
| * Copyright (c) 2006 SUSE Linux Products GmbH |
| * Copyright (c) 2006 Tejun Heo <teheo@suse.de> |
| */ |
| |
| #include <linux/device.h> |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| #include <linux/percpu.h> |
| |
| #include <asm/sections.h> |
| |
| #include "base.h" |
| #include "trace.h" |
| |
| struct devres_node { |
| struct list_head entry; |
| dr_release_t release; |
| const char *name; |
| size_t size; |
| }; |
| |
| struct devres { |
| struct devres_node node; |
| /* |
| * Some archs want to perform DMA into kmalloc caches |
| * and need a guaranteed alignment larger than |
| * the alignment of a 64-bit integer. |
| * Thus we use ARCH_KMALLOC_MINALIGN here and get exactly the same |
| * buffer alignment as if it was allocated by plain kmalloc(). |
| */ |
| u8 __aligned(ARCH_KMALLOC_MINALIGN) data[]; |
| }; |
| |
| struct devres_group { |
| struct devres_node node[2]; |
| void *id; |
| int color; |
| /* -- 8 pointers */ |
| }; |
| |
| static void set_node_dbginfo(struct devres_node *node, const char *name, |
| size_t size) |
| { |
| node->name = name; |
| node->size = size; |
| } |
| |
| #ifdef CONFIG_DEBUG_DEVRES |
| static int log_devres = 0; |
| module_param_named(log, log_devres, int, S_IRUGO | S_IWUSR); |
| |
| static void devres_dbg(struct device *dev, struct devres_node *node, |
| const char *op) |
| { |
| if (unlikely(log_devres)) |
| dev_err(dev, "DEVRES %3s %p %s (%zu bytes)\n", |
| op, node, node->name, node->size); |
| } |
| #else /* CONFIG_DEBUG_DEVRES */ |
| #define devres_dbg(dev, node, op) do {} while (0) |
| #endif /* CONFIG_DEBUG_DEVRES */ |
| |
| static void devres_log(struct device *dev, struct devres_node *node, |
| const char *op) |
| { |
| trace_devres_log(dev, op, node, node->name, node->size); |
| devres_dbg(dev, node, op); |
| } |
| |
| /* |
| * Release functions for devres group. These callbacks are used only |
| * for identification. |
| */ |
| static void group_open_release(struct device *dev, void *res) |
| { |
| /* noop */ |
| } |
| |
| static void group_close_release(struct device *dev, void *res) |
| { |
| /* noop */ |
| } |
| |
| static struct devres_group * node_to_group(struct devres_node *node) |
| { |
| if (node->release == &group_open_release) |
| return container_of(node, struct devres_group, node[0]); |
| if (node->release == &group_close_release) |
| return container_of(node, struct devres_group, node[1]); |
| return NULL; |
| } |
| |
| static bool check_dr_size(size_t size, size_t *tot_size) |
| { |
| /* We must catch any near-SIZE_MAX cases that could overflow. */ |
| if (unlikely(check_add_overflow(sizeof(struct devres), |
| size, tot_size))) |
| return false; |
| |
| return true; |
| } |
| |
| static __always_inline struct devres * alloc_dr(dr_release_t release, |
| size_t size, gfp_t gfp, int nid) |
| { |
| size_t tot_size; |
| struct devres *dr; |
| |
| if (!check_dr_size(size, &tot_size)) |
| return NULL; |
| |
| dr = kmalloc_node_track_caller(tot_size, gfp, nid); |
| if (unlikely(!dr)) |
| return NULL; |
| |
| /* No need to clear memory twice */ |
| if (!(gfp & __GFP_ZERO)) |
| memset(dr, 0, offsetof(struct devres, data)); |
| |
| INIT_LIST_HEAD(&dr->node.entry); |
| dr->node.release = release; |
| return dr; |
| } |
| |
| static void add_dr(struct device *dev, struct devres_node *node) |
| { |
| devres_log(dev, node, "ADD"); |
| BUG_ON(!list_empty(&node->entry)); |
| list_add_tail(&node->entry, &dev->devres_head); |
| } |
| |
| static void replace_dr(struct device *dev, |
| struct devres_node *old, struct devres_node *new) |
| { |
| devres_log(dev, old, "REPLACE"); |
| BUG_ON(!list_empty(&new->entry)); |
| list_replace(&old->entry, &new->entry); |
| } |
| |
| /** |
| * __devres_alloc_node - Allocate device resource data |
| * @release: Release function devres will be associated with |
| * @size: Allocation size |
| * @gfp: Allocation flags |
| * @nid: NUMA node |
| * @name: Name of the resource |
| * |
| * Allocate devres of @size bytes. The allocated area is zeroed, then |
| * associated with @release. The returned pointer can be passed to |
| * other devres_*() functions. |
| * |
| * RETURNS: |
| * Pointer to allocated devres on success, NULL on failure. |
| */ |
| void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp, int nid, |
| const char *name) |
| { |
| struct devres *dr; |
| |
| dr = alloc_dr(release, size, gfp | __GFP_ZERO, nid); |
| if (unlikely(!dr)) |
| return NULL; |
| set_node_dbginfo(&dr->node, name, size); |
| return dr->data; |
| } |
| EXPORT_SYMBOL_GPL(__devres_alloc_node); |
| |
| /** |
| * 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 |
| * |
| * Free devres created with devres_alloc(). |
| */ |
| void devres_free(void *res) |
| { |
| if (res) { |
| struct devres *dr = container_of(res, struct devres, data); |
| |
| BUG_ON(!list_empty(&dr->node.entry)); |
| kfree(dr); |
| } |
| } |
| EXPORT_SYMBOL_GPL(devres_free); |
| |
| /** |
| * devres_add - Register device resource |
| * @dev: Device to add resource to |
| * @res: Resource to register |
| * |
| * Register devres @res to @dev. @res should have been allocated |
| * using devres_alloc(). On driver detach, the associated release |
| * function will be invoked and devres will be freed automatically. |
| */ |
| void devres_add(struct device *dev, void *res) |
| { |
| struct devres *dr = container_of(res, struct devres, data); |
| unsigned long flags; |
| |
| spin_lock_irqsave(&dev->devres_lock, flags); |
| add_dr(dev, &dr->node); |
| spin_unlock_irqrestore(&dev->devres_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(devres_add); |
| |
| static struct devres *find_dr(struct device *dev, dr_release_t release, |
| dr_match_t match, void *match_data) |
| { |
| struct devres_node *node; |
| |
| list_for_each_entry_reverse(node, &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; |
| return dr; |
| } |
| |
| return NULL; |
| } |
| |
| /** |
| * devres_find - Find device resource |
| * @dev: Device to lookup 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 which is associated with @release |
| * and for which @match returns 1. If @match is NULL, it's considered |
| * to match all. |
| * |
| * RETURNS: |
| * Pointer to found devres, NULL if not found. |
| */ |
| void * devres_find(struct device *dev, dr_release_t release, |
| dr_match_t match, void *match_data) |
| { |
| struct devres *dr; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&dev->devres_lock, flags); |
| dr = find_dr(dev, release, match, match_data); |
| spin_unlock_irqrestore(&dev->devres_lock, flags); |
| |
| if (dr) |
| return dr->data; |
| return NULL; |
| } |
| EXPORT_SYMBOL_GPL(devres_find); |
| |
| /** |
| * devres_get - Find devres, if non-existent, add one atomically |
| * @dev: Device to lookup or add devres for |
| * @new_res: Pointer to new initialized devres to add if not found |
| * @match: Match function (optional) |
| * @match_data: Data for the match function |
| * |
| * Find the latest devres of @dev which has the same release function |
| * as @new_res and for which @match return 1. If found, @new_res is |
| * freed; otherwise, @new_res is added atomically. |
| * |
| * RETURNS: |
| * Pointer to found or added devres. |
| */ |
| void * devres_get(struct device *dev, void *new_res, |
| dr_match_t match, void *match_data) |
| { |
| struct devres *new_dr = container_of(new_res, struct devres, data); |
| struct devres *dr; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&dev->devres_lock, flags); |
| dr = find_dr(dev, new_dr->node.release, match, match_data); |
| if (!dr) { |
| add_dr(dev, &new_dr->node); |
| dr = new_dr; |
| new_res = NULL; |
| } |
| spin_unlock_irqrestore(&dev->devres_lock, flags); |
| devres_free(new_res); |
| |
| return dr->data; |
| } |
| EXPORT_SYMBOL_GPL(devres_get); |
| |
| /** |
| * devres_remove - Find a device resource and remove it |
| * @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 and |
| * returned. |
| * |
| * RETURNS: |
| * Pointer to removed devres on success, NULL if not found. |
| */ |
| void * devres_remove(struct device *dev, dr_release_t release, |
| dr_match_t match, void *match_data) |
| { |
| struct devres *dr; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&dev->devres_lock, flags); |
| dr = find_dr(dev, release, match, match_data); |
| if (dr) { |
| list_del_init(&dr->node.entry); |
| devres_log(dev, &dr->node, "REM"); |
| } |
| spin_unlock_irqrestore(&dev->devres_lock, flags); |
| |
| if (dr) |
| return dr->data; |
| return NULL; |
| } |
| EXPORT_SYMBOL_GPL(devres_remove); |
| |
| /** |
| * devres_destroy - Find a device resource and destroy it |
| * @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 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. |
| */ |
| int devres_destroy(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; |
| |
| devres_free(res); |
| return 0; |
| } |
| 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) |
| { |
| struct devres_node *node, *n; |
| int cnt = 0, nr_groups = 0; |
| |
| /* First pass - move normal devres entries to @todo and clear |
| * devres_group colors. |
| */ |
| node = list_entry(first, struct devres_node, entry); |
| list_for_each_entry_safe_from(node, n, end, entry) { |
| struct devres_group *grp; |
| |
| grp = node_to_group(node); |
| if (grp) { |
| /* clear color of group markers in the first pass */ |
| grp->color = 0; |
| nr_groups++; |
| } else { |
| /* regular devres entry */ |
| if (&node->entry == first) |
| first = first->next; |
| list_move_tail(&node->entry, todo); |
| cnt++; |
| } |
| } |
| |
| if (!nr_groups) |
| return cnt; |
| |
| /* Second pass - Scan groups and color them. A group gets |
| * color value of two iff the group is wholly contained in |
| * [current node, end). That is, for a closed group, both opening |
| * and closing markers should be in the range, while just the |
| * opening marker is enough for an open group. |
| */ |
| node = list_entry(first, struct devres_node, entry); |
| list_for_each_entry_safe_from(node, n, end, entry) { |
| struct devres_group *grp; |
| |
| grp = node_to_group(node); |
| BUG_ON(!grp || list_empty(&grp->node[0].entry)); |
| |
| grp->color++; |
| if (list_empty(&grp->node[1].entry)) |
| grp->color++; |
| |
| BUG_ON(grp->color <= 0 || grp->color > 2); |
| if (grp->color == 2) { |
| /* No need to update current node or end. The removed |
| * nodes are always before both. |
| */ |
| list_move_tail(&grp->node[0].entry, todo); |
| list_del_init(&grp->node[1].entry); |
| } |
| } |
| |
| return cnt; |
| } |
| |
| static void release_nodes(struct device *dev, struct list_head *todo) |
| { |
| struct devres *dr, *tmp; |
| |
| /* Release. Note that both devres and devres_group are |
| * handled as devres in the following loop. This is safe. |
| */ |
| list_for_each_entry_safe_reverse(dr, tmp, todo, node.entry) { |
| devres_log(dev, &dr->node, "REL"); |
| dr->node.release(dev, dr->data); |
| kfree(dr); |
| } |
| } |
| |
| /** |
| * devres_release_all - Release all managed resources |
| * @dev: Device to release resources for |
| * |
| * Release all resources associated with @dev. This function is |
| * called on driver detach. |
| */ |
| int devres_release_all(struct device *dev) |
| { |
| unsigned long flags; |
| LIST_HEAD(todo); |
| int cnt; |
| |
| /* Looks like an uninitialized device structure */ |
| if (WARN_ON(dev->devres_head.next == NULL)) |
| return -ENODEV; |
| |
| /* Nothing to release if list is empty */ |
| if (list_empty(&dev->devres_head)) |
| return 0; |
| |
| spin_lock_irqsave(&dev->devres_lock, flags); |
| cnt = remove_nodes(dev, dev->devres_head.next, &dev->devres_head, &todo); |
| spin_unlock_irqrestore(&dev->devres_lock, flags); |
| |
| release_nodes(dev, &todo); |
| return cnt; |
| } |
| |
| /** |
| * devres_open_group - Open a new devres group |
| * @dev: Device to open devres group for |
| * @id: Separator ID |
| * @gfp: Allocation flags |
| * |
| * Open a new devres group for @dev with @id. For @id, using a |
| * pointer to an object which won't be used for another group is |
| * recommended. If @id is NULL, address-wise unique ID is created. |
| * |
| * RETURNS: |
| * ID of the new group, NULL on failure. |
| */ |
| void * devres_open_group(struct device *dev, void *id, gfp_t gfp) |
| { |
| struct devres_group *grp; |
| unsigned long flags; |
| |
| grp = kmalloc(sizeof(*grp), gfp); |
| if (unlikely(!grp)) |
| return NULL; |
| |
| grp->node[0].release = &group_open_release; |
| grp->node[1].release = &group_close_release; |
| INIT_LIST_HEAD(&grp->node[0].entry); |
| INIT_LIST_HEAD(&grp->node[1].entry); |
| set_node_dbginfo(&grp->node[0], "grp<", 0); |
| set_node_dbginfo(&grp->node[1], "grp>", 0); |
| grp->id = grp; |
| if (id) |
| grp->id = id; |
| |
| spin_lock_irqsave(&dev->devres_lock, flags); |
| add_dr(dev, &grp->node[0]); |
| spin_unlock_irqrestore(&dev->devres_lock, flags); |
| return grp->id; |
| } |
| EXPORT_SYMBOL_GPL(devres_open_group); |
| |
| /* Find devres group with ID @id. If @id is NULL, look for the latest. */ |
| static struct devres_group * find_group(struct device *dev, void *id) |
| { |
| struct devres_node *node; |
| |
| list_for_each_entry_reverse(node, &dev->devres_head, entry) { |
| struct devres_group *grp; |
| |
| if (node->release != &group_open_release) |
| continue; |
| |
| grp = container_of(node, struct devres_group, node[0]); |
| |
| if (id) { |
| if (grp->id == id) |
| return grp; |
| } else if (list_empty(&grp->node[1].entry)) |
| return grp; |
| } |
| |
| return NULL; |
| } |
| |
| /** |
| * devres_close_group - Close a devres group |
| * @dev: Device to close devres group for |
| * @id: ID of target group, can be NULL |
| * |
| * Close the group identified by @id. If @id is NULL, the latest open |
| * group is selected. |
| */ |
| void devres_close_group(struct device *dev, void *id) |
| { |
| struct devres_group *grp; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&dev->devres_lock, flags); |
| |
| grp = find_group(dev, id); |
| if (grp) |
| add_dr(dev, &grp->node[1]); |
| else |
| WARN_ON(1); |
| |
| spin_unlock_irqrestore(&dev->devres_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(devres_close_group); |
| |
| /** |
| * devres_remove_group - Remove a devres group |
| * @dev: Device to remove group for |
| * @id: ID of target group, can be NULL |
| * |
| * Remove the group identified by @id. If @id is NULL, the latest |
| * open group is selected. Note that removing a group doesn't affect |
| * any other resources. |
| */ |
| void devres_remove_group(struct device *dev, void *id) |
| { |
| struct devres_group *grp; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&dev->devres_lock, flags); |
| |
| grp = find_group(dev, id); |
| if (grp) { |
| list_del_init(&grp->node[0].entry); |
| list_del_init(&grp->node[1].entry); |
| devres_log(dev, &grp->node[0], "REM"); |
| } else |
| WARN_ON(1); |
| |
| spin_unlock_irqrestore(&dev->devres_lock, flags); |
| |
| kfree(grp); |
| } |
| EXPORT_SYMBOL_GPL(devres_remove_group); |
| |
| /** |
| * devres_release_group - Release resources in a devres group |
| * @dev: Device to release group for |
| * @id: ID of target group, can be NULL |
| * |
| * Release all resources in the group identified by @id. If @id is |
| * NULL, the latest open group is selected. The selected group and |
| * groups properly nested inside the selected group are removed. |
| * |
| * RETURNS: |
| * The number of released non-group resources. |
| */ |
| int devres_release_group(struct device *dev, void *id) |
| { |
| struct devres_group *grp; |
| unsigned long flags; |
| LIST_HEAD(todo); |
| int cnt = 0; |
| |
| spin_lock_irqsave(&dev->devres_lock, flags); |
| |
| grp = find_group(dev, id); |
| if (grp) { |
| struct list_head *first = &grp->node[0].entry; |
| struct list_head *end = &dev->devres_head; |
| |
| if (!list_empty(&grp->node[1].entry)) |
| end = grp->node[1].entry.next; |
| |
| cnt = remove_nodes(dev, first, end, &todo); |
| spin_unlock_irqrestore(&dev->devres_lock, flags); |
| |
| release_nodes(dev, &todo); |
| } else { |
| WARN_ON(1); |
| spin_unlock_irqrestore(&dev->devres_lock, flags); |
| } |
| |
| return cnt; |
| } |
| EXPORT_SYMBOL_GPL(devres_release_group); |
| |
| /* |
| * Custom devres actions allow inserting a simple function call |
| * into the teardown 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); |
| |
| /** |
| * devm_release_action() - release previously added custom action |
| * @dev: Device that owns the action |
| * @action: Function implementing the action |
| * @data: Pointer to data passed to @action implementation |
| * |
| * Releases and removes instance of @action previously added by |
| * devm_add_action(). Both action and data should match one of the |
| * existing entries. |
| */ |
| void devm_release_action(struct device *dev, void (*action)(void *), void *data) |
| { |
| struct action_devres devres = { |
| .data = data, |
| .action = action, |
| }; |
| |
| WARN_ON(devres_release(dev, devm_action_release, devm_action_match, |
| &devres)); |
| |
| } |
| EXPORT_SYMBOL_GPL(devm_release_action); |
| |
| /* |
| * Managed kmalloc/kfree |
| */ |
| static void devm_kmalloc_release(struct device *dev, void *res) |
| { |
| /* noop */ |
| } |
| |
| static int devm_kmalloc_match(struct device *dev, void *res, void *data) |
| { |
| return res == data; |
| } |
| |
| /** |
| * devm_kmalloc - Resource-managed kmalloc |
| * @dev: Device to allocate memory for |
| * @size: Allocation size |
| * @gfp: Allocation gfp flags |
| * |
| * 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_kmalloc(struct device *dev, size_t size, gfp_t gfp) |
| { |
| struct devres *dr; |
| |
| if (unlikely(!size)) |
| return ZERO_SIZE_PTR; |
| |
| /* use raw alloc_dr for kmalloc caller tracing */ |
| dr = alloc_dr(devm_kmalloc_release, size, gfp, dev_to_node(dev)); |
| 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_kmalloc); |
| |
| /** |
| * devm_krealloc - Resource-managed krealloc() |
| * @dev: Device to re-allocate memory for |
| * @ptr: Pointer to the memory chunk to re-allocate |
| * @new_size: New allocation size |
| * @gfp: Allocation gfp flags |
| * |
| * Managed krealloc(). Resizes the memory chunk allocated with devm_kmalloc(). |
| * Behaves similarly to regular krealloc(): if @ptr is NULL or ZERO_SIZE_PTR, |
| * it's the equivalent of devm_kmalloc(). If new_size is zero, it frees the |
| * previously allocated memory and returns ZERO_SIZE_PTR. This function doesn't |
| * change the order in which the release callback for the re-alloc'ed devres |
| * will be called (except when falling back to devm_kmalloc() or when freeing |
| * resources when new_size is zero). The contents of the memory are preserved |
| * up to the lesser of new and old sizes. |
| */ |
| void *devm_krealloc(struct device *dev, void *ptr, size_t new_size, gfp_t gfp) |
| { |
| size_t total_new_size, total_old_size; |
| struct devres *old_dr, *new_dr; |
| unsigned long flags; |
| |
| if (unlikely(!new_size)) { |
| devm_kfree(dev, ptr); |
| return ZERO_SIZE_PTR; |
| } |
| |
| if (unlikely(ZERO_OR_NULL_PTR(ptr))) |
| return devm_kmalloc(dev, new_size, gfp); |
| |
| if (WARN_ON(is_kernel_rodata((unsigned long)ptr))) |
| /* |
| * We cannot reliably realloc a const string returned by |
| * devm_kstrdup_const(). |
| */ |
| return NULL; |
| |
| if (!check_dr_size(new_size, &total_new_size)) |
| return NULL; |
| |
| total_old_size = ksize(container_of(ptr, struct devres, data)); |
| if (total_old_size == 0) { |
| WARN(1, "Pointer doesn't point to dynamically allocated memory."); |
| return NULL; |
| } |
| |
| /* |
| * If new size is smaller or equal to the actual number of bytes |
| * allocated previously - just return the same pointer. |
| */ |
| if (total_new_size <= total_old_size) |
| return ptr; |
| |
| /* |
| * Otherwise: allocate new, larger chunk. We need to allocate before |
| * taking the lock as most probably the caller uses GFP_KERNEL. |
| */ |
| new_dr = alloc_dr(devm_kmalloc_release, |
| total_new_size, gfp, dev_to_node(dev)); |
| if (!new_dr) |
| return NULL; |
| |
| /* |
| * The spinlock protects the linked list against concurrent |
| * modifications but not the resource itself. |
| */ |
| spin_lock_irqsave(&dev->devres_lock, flags); |
| |
| old_dr = find_dr(dev, devm_kmalloc_release, devm_kmalloc_match, ptr); |
| if (!old_dr) { |
| spin_unlock_irqrestore(&dev->devres_lock, flags); |
| kfree(new_dr); |
| WARN(1, "Memory chunk not managed or managed by a different device."); |
| return NULL; |
| } |
| |
| replace_dr(dev, &old_dr->node, &new_dr->node); |
| |
| spin_unlock_irqrestore(&dev->devres_lock, flags); |
| |
| /* |
| * We can copy the memory contents after releasing the lock as we're |
| * no longer modifying the list links. |
| */ |
| memcpy(new_dr->data, old_dr->data, |
| total_old_size - offsetof(struct devres, data)); |
| /* |
| * Same for releasing the old devres - it's now been removed from the |
| * list. This is also the reason why we must not use devm_kfree() - the |
| * links are no longer valid. |
| */ |
| kfree(old_dr); |
| |
| return new_dr->data; |
| } |
| EXPORT_SYMBOL_GPL(devm_krealloc); |
| |
| /** |
| * 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_kstrdup_const - resource managed conditional string duplication |
| * @dev: device for which to duplicate the string |
| * @s: the string to duplicate |
| * @gfp: the GFP mask used in the kmalloc() call when allocating memory |
| * |
| * Strings allocated by devm_kstrdup_const will be automatically freed when |
| * the associated device is detached. |
| * |
| * RETURNS: |
| * Source string if it is in .rodata section otherwise it falls back to |
| * devm_kstrdup. |
| */ |
| const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp) |
| { |
| if (is_kernel_rodata((unsigned long)s)) |
| return s; |
| |
| return devm_kstrdup(dev, s, gfp); |
| } |
| EXPORT_SYMBOL_GPL(devm_kstrdup_const); |
| |
| /** |
| * devm_kvasprintf - Allocate resource managed space and format a string |
| * into that. |
| * @dev: Device to allocate memory for |
| * @gfp: the GFP mask used in the devm_kmalloc() call when |
| * allocating memory |
| * @fmt: The printf()-style format string |
| * @ap: Arguments for the format string |
| * RETURNS: |
| * Pointer to allocated string on success, NULL on failure. |
| */ |
| char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt, |
| va_list ap) |
| { |
| unsigned int len; |
| char *p; |
| va_list aq; |
| |
| va_copy(aq, ap); |
| len = vsnprintf(NULL, 0, fmt, aq); |
| va_end(aq); |
| |
| p = devm_kmalloc(dev, len+1, gfp); |
| if (!p) |
| return NULL; |
| |
| vsnprintf(p, len+1, fmt, ap); |
| |
| return p; |
| } |
| EXPORT_SYMBOL(devm_kvasprintf); |
| |
| /** |
| * devm_kasprintf - Allocate resource managed space and format a string |
| * into that. |
| * @dev: Device to allocate memory for |
| * @gfp: the GFP mask used in the devm_kmalloc() call when |
| * allocating memory |
| * @fmt: The printf()-style format string |
| * @...: Arguments for the format string |
| * RETURNS: |
| * Pointer to allocated string on success, NULL on failure. |
| */ |
| char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...) |
| { |
| va_list ap; |
| char *p; |
| |
| va_start(ap, fmt); |
| p = devm_kvasprintf(dev, gfp, fmt, ap); |
| va_end(ap); |
| |
| return p; |
| } |
| EXPORT_SYMBOL_GPL(devm_kasprintf); |
| |
| /** |
| * devm_kfree - Resource-managed kfree |
| * @dev: Device this memory belongs to |
| * @p: Memory to free |
| * |
| * Free memory allocated with devm_kmalloc(). |
| */ |
| void devm_kfree(struct device *dev, const void *p) |
| { |
| int rc; |
| |
| /* |
| * Special cases: pointer to a string in .rodata returned by |
| * devm_kstrdup_const() or NULL/ZERO ptr. |
| */ |
| if (unlikely(is_kernel_rodata((unsigned long)p) || ZERO_OR_NULL_PTR(p))) |
| return; |
| |
| rc = devres_destroy(dev, devm_kmalloc_release, |
| devm_kmalloc_match, (void *)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); |
| |
| static void devm_percpu_release(struct device *dev, void *pdata) |
| { |
| void __percpu *p; |
| |
| p = *(void __percpu **)pdata; |
| free_percpu(p); |
| } |
| |
| static int devm_percpu_match(struct device *dev, void *data, void *p) |
| { |
| struct devres *devr = container_of(data, struct devres, data); |
| |
| return *(void **)devr->data == p; |
| } |
| |
| /** |
| * __devm_alloc_percpu - Resource-managed alloc_percpu |
| * @dev: Device to allocate per-cpu memory for |
| * @size: Size of per-cpu memory to allocate |
| * @align: Alignment of per-cpu memory to allocate |
| * |
| * Managed alloc_percpu. Per-cpu memory allocated with this function is |
| * automatically freed on driver detach. |
| * |
| * RETURNS: |
| * Pointer to allocated memory on success, NULL on failure. |
| */ |
| void __percpu *__devm_alloc_percpu(struct device *dev, size_t size, |
| size_t align) |
| { |
| void *p; |
| void __percpu *pcpu; |
| |
| pcpu = __alloc_percpu(size, align); |
| if (!pcpu) |
| return NULL; |
| |
| p = devres_alloc(devm_percpu_release, sizeof(void *), GFP_KERNEL); |
| if (!p) { |
| free_percpu(pcpu); |
| return NULL; |
| } |
| |
| *(void __percpu **)p = pcpu; |
| |
| devres_add(dev, p); |
| |
| return pcpu; |
| } |
| EXPORT_SYMBOL_GPL(__devm_alloc_percpu); |
| |
| /** |
| * devm_free_percpu - Resource-managed free_percpu |
| * @dev: Device this memory belongs to |
| * @pdata: Per-cpu memory to free |
| * |
| * Free memory allocated with devm_alloc_percpu(). |
| */ |
| void devm_free_percpu(struct device *dev, void __percpu *pdata) |
| { |
| WARN_ON(devres_destroy(dev, devm_percpu_release, devm_percpu_match, |
| (__force void *)pdata)); |
| } |
| EXPORT_SYMBOL_GPL(devm_free_percpu); |