3  *	linux/kernel/resource.c
8  * Arbitrary resource management.
35 struct resource ioport_resource = {
43 struct resource iomem_resource = {
59 static struct resource *next_resource(struct resource *p, bool skip_children,  in next_resource()
60 				      struct resource *subtree_root)  in next_resource()
73  * Traverse the resource subtree under @_root in pre-order, excluding
90 	struct resource *root = pde_data(file_inode(m->file));  in r_start()
91 	struct resource *p;  in r_start()
105 	struct resource *p = v;  in r_next()
120 	struct resource *root = pde_data(file_inode(m->file));  in r_show()
121 	struct resource *r = v, *p;  in r_show()
163 static void free_resource(struct resource *res)  in free_resource()
166 	 * If the resource was allocated using memblock early during boot  in free_resource()
169 	 * alloc_resource() overcomplicates resource handling.  in free_resource()
175 static struct resource *alloc_resource(gfp_t flags)  in alloc_resource()
177 	return kzalloc(sizeof(struct resource), flags);  in alloc_resource()
181 static struct resource * __request_resource(struct resource *root, struct resource *new)  in __request_resource()
185 	struct resource *tmp, **p;  in __request_resource()
209 static int __release_resource(struct resource *old, bool release_child)  in __release_resource()
211 	struct resource *tmp, **p, *chd;  in __release_resource()
238 static void __release_child_resources(struct resource *r)  in __release_child_resources()
240 	struct resource *tmp, *p;  in __release_child_resources()
253 		printk(KERN_DEBUG "release child resource %pR\n", tmp);  in __release_child_resources()
261 void release_child_resources(struct resource *r)  in release_child_resources()
269  * request_resource_conflict - request and reserve an I/O or memory resource
270  * @root: root resource descriptor
271  * @new: resource descriptor desired by caller
273  * Returns 0 for success, conflict resource on error.
275 struct resource *request_resource_conflict(struct resource *root, struct resource *new)  in request_resource_conflict()
277 	struct resource *conflict;  in request_resource_conflict()
286  * request_resource - request and reserve an I/O or memory resource
287  * @root: root resource descriptor
288  * @new: resource descriptor desired by caller
292 int request_resource(struct resource *root, struct resource *new)  in request_resource()
294 	struct resource *conflict;  in request_resource()
303  * release_resource - release a previously reserved resource
304  * @old: resource pointer
306 int release_resource(struct resource *old)  in release_resource()
318 static bool is_type_match(struct resource *p, unsigned long flags, unsigned long desc)  in is_type_match()
324  * find_next_iomem_res - Finds the lowest iomem resource that covers part of
327  * If a resource is found, returns 0 and @*res is overwritten with the part
328  * of the resource that's within [@start..@end]; if none is found, returns
331  * @start:	start address of the resource searched for
332  * @end:	end address of same resource
333  * @flags:	flags which the resource must have
334  * @desc:	descriptor the resource must have
335  * @res:	return ptr, if resource found
342 			       struct resource *res)  in find_next_iomem_res()
344 	struct resource *p;  in find_next_iomem_res()
355 		/* If we passed the resource we are looking for, stop */  in find_next_iomem_res()
372 		*res = (struct resource) {  in find_next_iomem_res()
388 				 int (*func)(struct resource *, void *))  in __walk_iomem_res_desc()  argument
390 	struct resource res;  in __walk_iomem_res_desc()
407  *			 with matching resource ranges.
409  * @desc: I/O resource descriptor. Use IORES_DESC_NONE to skip @desc check.
410  * @flags: I/O resource flags
414  * @func: callback function that is called for each qualifying resource area
420  * <linux/ioport.h> and set it in 'desc' of a target resource entry.
423 		u64 end, void *arg, int (*func)(struct resource *, void *))  in walk_iomem_res_desc()  argument
437 			int (*func)(struct resource *, void *))  in walk_system_ram_res()  argument
452 				int (*func)(struct resource *, void *))  in walk_system_ram_res_rev()  argument
454 	struct resource res, *rams;  in walk_system_ram_res_rev()
460 	rams = kvcalloc(rams_size, sizeof(struct resource), GFP_KERNEL);  in walk_system_ram_res_rev()
470 			struct resource *rams_new;  in walk_system_ram_res_rev()
472 			rams_new = kvrealloc(rams, (rams_size + 16) * sizeof(struct resource),  in walk_system_ram_res_rev()
502 		 int (*func)(struct resource *, void *))  in walk_mem_res()  argument
520 	struct resource res;  in walk_system_ram_range()
555 static int __region_intersects(struct resource *parent, resource_size_t start,  in __region_intersects()
560 	struct resource *p, *dp;  in __region_intersects()
561 	struct resource res, o;  in __region_intersects()
581 		 * will behave similar as the following fake resource  in __region_intersects()
594 				 * isn't covered by matched resource.  in __region_intersects()
623  * @flags: flags of resource (in iomem_resource)
624  * @desc: descriptor of resource (in iomem_resource) or IORES_DESC_NONE
627  * resource identified by @flags and @desc (optional with IORES_DESC_NONE).
630  * resource, and return REGION_INTERSECTS if the region overlaps @flags/@desc
631  * and no other defined resource. Note that REGION_INTERSECTS is also
637  * through the resource table page by page.
652 void __weak arch_remove_reservations(struct resource *avail)  in arch_remove_reservations()
656 static void resource_clip(struct resource *res, resource_size_t min,  in resource_clip()
666  * Find empty space in the resource tree with the given range and
669 static int __find_resource_space(struct resource *root, struct resource *old,  in __find_resource_space()
670 				 struct resource *new, resource_size_t size,  in __find_resource_space()
673 	struct resource *this = root->child;  in __find_resource_space()
674 	struct resource tmp = *new, avail, alloc;  in __find_resource_space()
679 	 * Skip past an allocated resource that starts at 0, since the assignment  in __find_resource_space()
730  * find_resource_space - Find empty space in the resource tree
731  * @root:	Root resource descriptor
732  * @new:	Resource descriptor awaiting an empty resource space
736  * Finds an empty space under @root in the resource tree satisfying range and
743 int find_resource_space(struct resource *root, struct resource *new,  in find_resource_space()
752  * reallocate_resource - allocate a slot in the resource tree given range & alignment.
753  *	The resource will be relocated if the new size cannot be reallocated in the
756  * @root: root resource descriptor
757  * @old:  resource descriptor desired by caller
758  * @newsize: new size of the resource descriptor
761 static int reallocate_resource(struct resource *root, struct resource *old,  in reallocate_resource()
766 	struct resource new = *old;  in reallocate_resource()
767 	struct resource *conflict;  in reallocate_resource()
801  * allocate_resource - allocate empty slot in the resource tree given range & alignment.
802  * 	The resource will be reallocated with a new size if it was already allocated
803  * @root: root resource descriptor
804  * @new: resource descriptor desired by caller
805  * @size: requested resource region size
812 int allocate_resource(struct resource *root, struct resource *new,  in allocate_resource()
828 		/* resource is already allocated, try reallocating with  in allocate_resource()
844  * lookup_resource - find an existing resource by a resource start address
845  * @root: root resource descriptor
846  * @start: resource start address
848  * Returns a pointer to the resource if found, NULL otherwise
850 struct resource *lookup_resource(struct resource *root, resource_size_t start)  in lookup_resource()
852 	struct resource *res;  in lookup_resource()
865  * Insert a resource into the resource tree. If successful, return NULL,
866  * otherwise return the conflicting resource (compare to __request_resource())
868 static struct resource * __insert_resource(struct resource *parent, struct resource *new)  in __insert_resource()
870 	struct resource *first, *next;  in __insert_resource()
918  * insert_resource_conflict - Inserts resource in the resource tree
919  * @parent: parent of the new resource
920  * @new: new resource to insert
922  * Returns 0 on success, conflict resource if the resource can't be inserted.
926  * entirely fit within the range of the new resource, then the new
927  * resource is inserted and the conflicting resources become children of
928  * the new resource.
933 struct resource *insert_resource_conflict(struct resource *parent, struct resource *new)  in insert_resource_conflict()
935 	struct resource *conflict;  in insert_resource_conflict()
944  * insert_resource - Inserts a resource in the resource tree
945  * @parent: parent of the new resource
946  * @new: new resource to insert
948  * Returns 0 on success, -EBUSY if the resource can't be inserted.
953 int insert_resource(struct resource *parent, struct resource *new)  in insert_resource()
955 	struct resource *conflict;  in insert_resource()
963  * insert_resource_expand_to_fit - Insert a resource into the resource tree
964  * @root: root resource descriptor
965  * @new: new resource to insert
967  * Insert a resource into the resource tree, possibly expanding it in order
970 void insert_resource_expand_to_fit(struct resource *root, struct resource *new)  in insert_resource_expand_to_fit()
977 		struct resource *conflict;  in insert_resource_expand_to_fit()
985 		/* Ok, expand resource to cover the conflict, then try again .. */  in insert_resource_expand_to_fit()
991 		pr_info("Expanded resource %s due to conflict with %s\n", new->name, conflict->name);  in insert_resource_expand_to_fit()
997  * resource discovery, and late discovery of CXL resources are expected
1004  * remove_resource - Remove a resource in the resource tree
1005  * @old: resource to remove
1007  * Returns 0 on success, -EINVAL if the resource is not valid.
1009  * This function removes a resource previously inserted by insert_resource()
1012  * insert a new resource, and move any conflicting resources down to the
1013  * children of the new resource.
1018 int remove_resource(struct resource *old)  in remove_resource()
1029 static int __adjust_resource(struct resource *res, resource_size_t start,  in __adjust_resource()
1032 	struct resource *tmp, *parent = res->parent;  in __adjust_resource()
1067  * adjust_resource - modify a resource's start and size
1068  * @res: resource to modify
1072  * Given an existing resource, change its start and size to match the
1074  * Existing children of the resource are assumed to be immutable.
1076 int adjust_resource(struct resource *res, resource_size_t start,  in adjust_resource()
1089 __reserve_region_with_split(struct resource *root, resource_size_t start,  in __reserve_region_with_split()
1092 	struct resource *parent = root;  in __reserve_region_with_split()
1093 	struct resource *conflict;  in __reserve_region_with_split()
1094 	struct resource *res = alloc_resource(GFP_ATOMIC);  in __reserve_region_with_split()
1095 	struct resource *next_res = NULL;  in __reserve_region_with_split()
1150 reserve_region_with_split(struct resource *root, resource_size_t start,  in reserve_region_with_split()
1179  * resource_alignment - calculate resource's alignment
1180  * @res: resource pointer
1184 resource_size_t resource_alignment(struct resource *res)  in resource_alignment()
1212 static void revoke_iomem(struct resource *res)  in revoke_iomem()
1228 	 * the resource busy by this point, so devmem_is_allowed()  in revoke_iomem()
1230 	 * does not iterate the entire resource range.  in revoke_iomem()
1244 static void revoke_iomem(struct resource *res) {}  in revoke_iomem()
1258 static int __request_region_locked(struct resource *res, struct resource *parent,  in __request_region_locked()
1269 		struct resource *conflict;  in __request_region_locked()
1310  * __request_region - create a new busy resource region
1311  * @parent: parent resource descriptor
1312  * @start: resource start address
1313  * @n: resource region size
1315  * @flags: IO resource flags
1317 struct resource *__request_region(struct resource *parent,  in __request_region()
1321 	struct resource *res = alloc_resource(GFP_KERNEL);  in __request_region()
1344  * __release_region - release a previously reserved resource region
1345  * @parent: parent resource descriptor
1346  * @start: resource start address
1347  * @n: resource region size
1349  * The described resource region must match a currently busy region.
1351 void __release_region(struct resource *parent, resource_size_t start,  in __release_region()
1354 	struct resource **p;  in __release_region()
1363 		struct resource *res = *p;  in __release_region()
1386 	pr_warn("Trying to free nonexistent resource <%pa-%pa>\n", &start, &end);  in __release_region()
1393  * @start: resource start address
1394  * @size: resource region size
1397  * is released from a currently busy memory resource.  The requested region
1398  * must either match exactly or fit into a single busy resource entry.  In
1399  * the latter case, the remaining resource is adjusted accordingly.
1400  * Existing children of the busy memory resource must be immutable in the
1406  * - When a busy memory resource gets split into two entries, the code
1412 	struct resource *parent = &iomem_resource;  in release_mem_region_adjustable()
1413 	struct resource *new_res = NULL;  in release_mem_region_adjustable()
1415 	struct resource **p;  in release_mem_region_adjustable()
1416 	struct resource *res;  in release_mem_region_adjustable()
1440 		/* look for the next resource if it does not fit into */  in release_mem_region_adjustable()
1454 		/* found the target resource; let's adjust accordingly */  in release_mem_region_adjustable()
1468 			/* split into two entries - we need a new resource */  in release_mem_region_adjustable()
1502 static bool system_ram_resources_mergeable(struct resource *r1,  in system_ram_resources_mergeable()
1503 					   struct resource *r2)  in system_ram_resources_mergeable()
1512  * merge_system_ram_resource - mark the System RAM resource mergeable and try to
1514  * @res: resource descriptor
1518  * the actual resource boundaries are not of interest (e.g., it might be
1525  *   marked mergeable are used anymore after this call - the resource might
1529 void merge_system_ram_resource(struct resource *res)  in merge_system_ram_resource()
1532 	struct resource *cur;  in merge_system_ram_resource()
1562  * Managed region resource
1566 	struct resource **r = ptr;  in devm_resource_release()
1572  * devm_request_resource() - request and reserve an I/O or memory resource
1573  * @dev: device for which to request the resource
1574  * @root: root of the resource tree from which to request the resource
1575  * @new: descriptor of the resource to request
1580  * If for some reason the resource needs to be released explicitly, because
1585  * requested resource, an error message will be printed.
1589 int devm_request_resource(struct device *dev, struct resource *root,  in devm_request_resource()
1590 			  struct resource *new)  in devm_request_resource()
1592 	struct resource *conflict, **ptr;  in devm_request_resource()
1602 		dev_err(dev, "resource collision: %pR conflicts with %s %pR\n",  in devm_request_resource()
1615 	struct resource **ptr = res;  in devm_resource_match()
1621  * devm_release_resource() - release a previously requested resource
1622  * @dev: device for which to release the resource
1623  * @new: descriptor of the resource to release
1625  * Releases a resource previously requested using devm_request_resource().
1627 void devm_release_resource(struct device *dev, struct resource *new)  in devm_release_resource()
1635 	struct resource *parent;
1655 struct resource *
1656 __devm_request_region(struct device *dev, struct resource *parent,  in __devm_request_region()
1660 	struct resource *res;  in __devm_request_region()
1681 void __devm_release_region(struct device *dev, struct resource *parent,  in __devm_release_region()
1698 	static struct resource reserve[MAXRESERVE];  in reserve_setup()
1703 		struct resource *parent;  in reserve_setup()
1710 			struct resource *res = reserve + x;  in reserve_setup()
1739  * iomem resource tree.
1744 	struct resource *p;  in iomem_map_sanity_check()
1761 		 * if a resource is "BUSY", it's not a hardware resource  in iomem_map_sanity_check()
1762 		 * but a driver mapping of such a resource; we don't want  in iomem_map_sanity_check()
1769 		pr_warn("resource sanity check: requesting [mem %pa-%pa], which spans more than %s %pR\n",  in iomem_map_sanity_check()
1791 bool resource_is_exclusive(struct resource *root, u64 addr, resource_size_t size)  in resource_is_exclusive()
1796 	struct resource *p;  in resource_is_exclusive()
1821 		 * A resource is exclusive if IORESOURCE_EXCLUSIVE is set  in resource_is_exclusive()
1823 		 * resource is busy.  in resource_is_exclusive()
1844 struct resource_entry *resource_list_create_entry(struct resource *res,  in resource_list_create_entry()
1877 static resource_size_t gfr_start(struct resource *base, resource_size_t size,  in gfr_start()
1890 static bool gfr_continue(struct resource *base, resource_size_t addr,  in gfr_continue()
1913 	struct resource *res = _res;  in remove_free_mem_region()
1920 static struct resource *
1921 get_free_mem_region(struct device *dev, struct resource *base,  in get_free_mem_region()
1927 	struct resource *res;  in get_free_mem_region()
1985 			 * Only succeed if the resource hosts an exclusive  in get_free_mem_region()
2010  * @dev: device struct to bind the resource to
2012  * @base: resource tree to look in
2015  * contain the new resource, so that it can later be hotplugged as ZONE_DEVICE
2018 struct resource *devm_request_free_mem_region(struct device *dev,  in devm_request_free_mem_region()
2019 		struct resource *base, unsigned long size)  in devm_request_free_mem_region()
2029 struct resource *request_free_mem_region(struct resource *base,  in request_free_mem_region()
2041  * @base: resource that will parent the new resource
2044  * @name: resource name
2048  * Allocate and insert a new resource to cover a free, unclaimed by a
2051 struct resource *alloc_free_mem_region(struct resource *base,  in alloc_free_mem_region()
2055 	/* Default of ascending direction and insert resource */  in alloc_free_mem_region()