/* * drivers/base/devres.c - device resource management * * Copyright (c) 2006 SUSE Linux Products GmbH * Copyright (c) 2006 Tejun Heo <teheo@suse.de> * * This file is released under the GPLv2. */ #include <linux/device.h>#include <linux/module.h>#include <linux/slab.h> #include "base.h" struct devres_node { struct list_head entry; dr_release_t release;#ifdef CONFIG_DEBUG_DEVRES const char *name; size_t size;#endif}; struct devres { struct devres_node node; /* -- 3 pointers */ unsigned long long data[]; /* guarantee ull alignment */}; struct devres_group { struct devres_node node[2]; void *id; int color; /* -- 8 pointers */}; #ifdef CONFIG_DEBUG_DEVRESstatic int log_devres = 0;module_param_named(log, log_devres, int, S_IRUGO | S_IWUSR); static void set_node_dbginfo(struct devres_node *node, const char *name, size_t size){ node->name = name; node->size = size;} 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);}#else /* CONFIG_DEBUG_DEVRES */#define set_node_dbginfo(node, n, s) do {} while (0)#define devres_log(dev, node, op) do {} while (0)#endif /* CONFIG_DEBUG_DEVRES */ /* * 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 __always_inline struct devres * alloc_dr(dr_release_t release, size_t size, gfp_t gfp){ size_t tot_size = sizeof(struct devres) + size; struct devres *dr; dr = kmalloc_track_caller(tot_size, gfp); if (unlikely(!dr)) return NULL; memset(dr, 0, tot_size); 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);} #ifdef CONFIG_DEBUG_DEVRESvoid * __devres_alloc(dr_release_t release, size_t size, gfp_t gfp, const char *name){ struct devres *dr; dr = alloc_dr(release, size, gfp); if (unlikely(!dr)) return NULL; set_node_dbginfo(&dr->node, name, size); return dr->data;}EXPORT_SYMBOL_GPL(__devres_alloc);#else/** * devres_alloc - Allocate device resource data * @release: Release function devres will be associated with * @size: Allocation size * @gfp: Allocation flags * * 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(dr_release_t release, size_t size, gfp_t gfp){ struct devres *dr; dr = alloc_dr(release, size, gfp); if (unlikely(!dr)) return NULL; return dr->data;}EXPORT_SYMBOL_GPL(devres_alloc);#endif /** * 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_dr = NULL; } spin_unlock_irqrestore(&dev->devres_lock, flags); devres_free(new_dr); 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. * * 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); static int remove_nodes(struct device *dev, struct list_head *first, struct list_head *end, struct list_head *todo){ int cnt = 0, nr_groups = 0; struct list_head *cur; /* First pass - move normal devres entries to @todo and clear * devres_group colors. */ cur = first; while (cur != end) { struct devres_node *node; struct devres_group *grp; node = list_entry(cur, struct devres_node, entry); cur = cur->next; 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 * [cur, 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. */ cur = first; while (cur != end) { struct devres_node *node; struct devres_group *grp; node = list_entry(cur, struct devres_node, entry); cur = cur->next; 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 cur 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 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; struct devres *dr, *tmp; cnt = remove_nodes(dev, first, end, &todo); spin_unlock_irqrestore(&dev->devres_lock, flags); /* 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); } return cnt;} /** * 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; /* Looks like an uninitialized device structure */ if (WARN_ON(dev->devres_head.next == NULL)) return -ENODEV; spin_lock_irqsave(&dev->devres_lock, flags); return release_nodes(dev, dev->devres_head.next, &dev->devres_head, flags);} /** * 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;Lines 1–500 of 651. Load more
/* * drivers/base/devres.c - device resource management * * Copyright (c) 2006 SUSE Linux Products GmbH * Copyright (c) 2006 Tejun Heo <teheo@suse.de> * * This file is released under the GPLv2. */ #include <linux/device.h> #include <linux/module.h> #include <linux/slab.h> #include "base.h" struct devres_node { struct list_head entry; dr_release_t release; #ifdef CONFIG_DEBUG_DEVRES const char *name; size_t size; #endif }; struct devres { struct devres_node node; /* -- 3 pointers */ unsigned long long data[]; /* guarantee ull alignment */ }; struct devres_group { struct devres_node node[2]; void *id; int color; /* -- 8 pointers */ }; #ifdef CONFIG_DEBUG_DEVRES static int log_devres = 0; module_param_named(log, log_devres, int, S_IRUGO | S_IWUSR); static void set_node_dbginfo(struct devres_node *node, const char *name, size_t size) { node->name = name; node->size = size; } 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); } #else /* CONFIG_DEBUG_DEVRES */ #define set_node_dbginfo(node, n, s) do {} while (0) #define devres_log(dev, node, op) do {} while (0) #endif /* CONFIG_DEBUG_DEVRES */ /* * 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 __always_inline struct devres * alloc_dr(dr_release_t release, size_t size, gfp_t gfp) { size_t tot_size = sizeof(struct devres) + size; struct devres *dr; dr = kmalloc_track_caller(tot_size, gfp); if (unlikely(!dr)) return NULL; memset(dr, 0, tot_size); 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); } #ifdef CONFIG_DEBUG_DEVRES void * __devres_alloc(dr_release_t release, size_t size, gfp_t gfp, const char *name) { struct devres *dr; dr = alloc_dr(release, size, gfp); if (unlikely(!dr)) return NULL; set_node_dbginfo(&dr->node, name, size); return dr->data; } EXPORT_SYMBOL_GPL(__devres_alloc); #else /** * devres_alloc - Allocate device resource data * @release: Release function devres will be associated with * @size: Allocation size * @gfp: Allocation flags * * 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(dr_release_t release, size_t size, gfp_t gfp) { struct devres *dr; dr = alloc_dr(release, size, gfp); if (unlikely(!dr)) return NULL; return dr->data; } EXPORT_SYMBOL_GPL(devres_alloc); #endif /** * 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_dr = NULL; } spin_unlock_irqrestore(&dev->devres_lock, flags); devres_free(new_dr); 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. * * 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); static int remove_nodes(struct device *dev, struct list_head *first, struct list_head *end, struct list_head *todo) { int cnt = 0, nr_groups = 0; struct list_head *cur; /* First pass - move normal devres entries to @todo and clear * devres_group colors. */ cur = first; while (cur != end) { struct devres_node *node; struct devres_group *grp; node = list_entry(cur, struct devres_node, entry); cur = cur->next; 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 * [cur, 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. */ cur = first; while (cur != end) { struct devres_node *node; struct devres_group *grp; node = list_entry(cur, struct devres_node, entry); cur = cur->next; 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 cur 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 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; struct devres *dr, *tmp; cnt = remove_nodes(dev, first, end, &todo); spin_unlock_irqrestore(&dev->devres_lock, flags); /* 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); } return cnt; } /** * 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; /* Looks like an uninitialized device structure */ if (WARN_ON(dev->devres_head.next == NULL)) return -ENODEV; spin_lock_irqsave(&dev->devres_lock, flags); return release_nodes(dev, dev->devres_head.next, &dev->devres_head, flags); } /** * 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;