3  *	linux/kernel/resource.c
8  * Arbitrary resource management.
33 struct resource ioport_resource = {
41 struct resource iomem_resource = {
52 	resource_size_t (*alignf)(void *, const struct resource *,
59 static struct resource *next_resource(struct resource *p)  in next_resource()
68 static struct resource *next_resource_skip_children(struct resource *p)  in next_resource_skip_children()
82 	struct resource *p = v;  in r_next()
94 	struct resource *p = pde_data(file_inode(m->file));  in r_start()
110 	struct resource *root = pde_data(file_inode(m->file));  in r_show()
111 	struct resource *r = v, *p;  in r_show()
153 static void free_resource(struct resource *res)  in free_resource()
156 	 * If the resource was allocated using memblock early during boot  in free_resource()
159 	 * alloc_resource() overcomplicates resource handling.  in free_resource()
165 static struct resource *alloc_resource(gfp_t flags)  in alloc_resource()
167 	return kzalloc(sizeof(struct resource), flags);  in alloc_resource()
171 static struct resource * __request_resource(struct resource *root, struct resource *new)  in __request_resource()
175 	struct resource *tmp, **p;  in __request_resource()
199 static int __release_resource(struct resource *old, bool release_child)  in __release_resource()
201 	struct resource *tmp, **p, *chd;  in __release_resource()
228 static void __release_child_resources(struct resource *r)  in __release_child_resources()
230 	struct resource *tmp, *p;  in __release_child_resources()
243 		printk(KERN_DEBUG "release child resource %pR\n", tmp);  in __release_child_resources()
251 void release_child_resources(struct resource *r)  in release_child_resources()
259  * request_resource_conflict - request and reserve an I/O or memory resource
260  * @root: root resource descriptor
261  * @new: resource descriptor desired by caller
263  * Returns 0 for success, conflict resource on error.
265 struct resource *request_resource_conflict(struct resource *root, struct resource *new)  in request_resource_conflict()
267 	struct resource *conflict;  in request_resource_conflict()
276  * request_resource - request and reserve an I/O or memory resource
277  * @root: root resource descriptor
278  * @new: resource descriptor desired by caller
282 int request_resource(struct resource *root, struct resource *new)  in request_resource()
284 	struct resource *conflict;  in request_resource()
293  * release_resource - release a previously reserved resource
294  * @old: resource pointer
296 int release_resource(struct resource *old)  in release_resource()
309  * find_next_iomem_res - Finds the lowest iomem resource that covers part of
312  * If a resource is found, returns 0 and @*res is overwritten with the part
313  * of the resource that's within [@start..@end]; if none is found, returns
316  * @start:	start address of the resource searched for
317  * @end:	end address of same resource
318  * @flags:	flags which the resource must have
319  * @desc:	descriptor the resource must have
320  * @res:	return ptr, if resource found
327 			       struct resource *res)  in find_next_iomem_res()
329 	struct resource *p;  in find_next_iomem_res()
340 		/* If we passed the resource we are looking for, stop */  in find_next_iomem_res()
361 		*res = (struct resource) {  in find_next_iomem_res()
377 				 int (*func)(struct resource *, void *))  in __walk_iomem_res_desc()  argument
379 	struct resource res;  in __walk_iomem_res_desc()
396  *			 with matching resource ranges.
398  * @desc: I/O resource descriptor. Use IORES_DESC_NONE to skip @desc check.
399  * @flags: I/O resource flags
403  * @func: callback function that is called for each qualifying resource area
409  * <linux/ioport.h> and set it in 'desc' of a target resource entry.
412 		u64 end, void *arg, int (*func)(struct resource *, void *))  in walk_iomem_res_desc()  argument
426 			int (*func)(struct resource *, void *))  in walk_system_ram_res()  argument
439 		 int (*func)(struct resource *, void *))  in walk_mem_res()  argument
457 	struct resource res;  in walk_system_ram_range()
492 static int __region_intersects(struct resource *parent, resource_size_t start,  in __region_intersects()
498 	struct resource *p, *dp;  in __region_intersects()
500 	struct resource res;  in __region_intersects()
521 		 * will behave similar as the following fake resource  in __region_intersects()
538 				 * isn't covered by matched resource.  in __region_intersects()
567  * @flags: flags of resource (in iomem_resource)
568  * @desc: descriptor of resource (in iomem_resource) or IORES_DESC_NONE
571  * resource identified by @flags and @desc (optional with IORES_DESC_NONE).
574  * resource, and return REGION_INTERSECTS if the region overlaps @flags/@desc
575  * and no other defined resource. Note that REGION_INTERSECTS is also
581  * through the resource table page by page.
596 void __weak arch_remove_reservations(struct resource *avail)  in arch_remove_reservations()
601 					     const struct resource *avail,  in simple_align_resource()
608 static void resource_clip(struct resource *res, resource_size_t min,  in resource_clip()
618  * Find empty slot in the resource tree with the given range and
621 static int __find_resource(struct resource *root, struct resource *old,  in __find_resource()
622 			 struct resource *new,  in __find_resource()
626 	struct resource *this = root->child;  in __find_resource()
627 	struct resource tmp = *new, avail, alloc;  in __find_resource()
631 	 * Skip past an allocated resource that starts at 0, since the assignment  in __find_resource()
678  * Find empty slot in the resource tree given range and alignment.
680 static int find_resource(struct resource *root, struct resource *new,  in find_resource()
688  * reallocate_resource - allocate a slot in the resource tree given range & alignment.
689  *	The resource will be relocated if the new size cannot be reallocated in the
692  * @root: root resource descriptor
693  * @old:  resource descriptor desired by caller
694  * @newsize: new size of the resource descriptor
697 static int reallocate_resource(struct resource *root, struct resource *old,  in reallocate_resource()
702 	struct resource new = *old;  in reallocate_resource()
703 	struct resource *conflict;  in reallocate_resource()
737  * allocate_resource - allocate empty slot in the resource tree given range & alignment.
738  * 	The resource will be reallocated with a new size if it was already allocated
739  * @root: root resource descriptor
740  * @new: resource descriptor desired by caller
741  * @size: requested resource region size
748 int allocate_resource(struct resource *root, struct resource *new,  in allocate_resource()
752 						const struct resource *,  in allocate_resource()  argument
770 		/* resource is already allocated, try reallocating with  in allocate_resource()
786  * lookup_resource - find an existing resource by a resource start address
787  * @root: root resource descriptor
788  * @start: resource start address
790  * Returns a pointer to the resource if found, NULL otherwise
792 struct resource *lookup_resource(struct resource *root, resource_size_t start)  in lookup_resource()
794 	struct resource *res;  in lookup_resource()
807  * Insert a resource into the resource tree. If successful, return NULL,
808  * otherwise return the conflicting resource (compare to __request_resource())
810 static struct resource * __insert_resource(struct resource *parent, struct resource *new)  in __insert_resource()
812 	struct resource *first, *next;  in __insert_resource()
860  * insert_resource_conflict - Inserts resource in the resource tree
861  * @parent: parent of the new resource
862  * @new: new resource to insert
864  * Returns 0 on success, conflict resource if the resource can't be inserted.
868  * entirely fit within the range of the new resource, then the new
869  * resource is inserted and the conflicting resources become children of
870  * the new resource.
875 struct resource *insert_resource_conflict(struct resource *parent, struct resource *new)  in insert_resource_conflict()
877 	struct resource *conflict;  in insert_resource_conflict()
886  * insert_resource - Inserts a resource in the resource tree
887  * @parent: parent of the new resource
888  * @new: new resource to insert
890  * Returns 0 on success, -EBUSY if the resource can't be inserted.
895 int insert_resource(struct resource *parent, struct resource *new)  in insert_resource()
897 	struct resource *conflict;  in insert_resource()
905  * insert_resource_expand_to_fit - Insert a resource into the resource tree
906  * @root: root resource descriptor
907  * @new: new resource to insert
909  * Insert a resource into the resource tree, possibly expanding it in order
912 void insert_resource_expand_to_fit(struct resource *root, struct resource *new)  in insert_resource_expand_to_fit()
919 		struct resource *conflict;  in insert_resource_expand_to_fit()
927 		/* Ok, expand resource to cover the conflict, then try again .. */  in insert_resource_expand_to_fit()
933 		pr_info("Expanded resource %s due to conflict with %s\n", new->name, conflict->name);  in insert_resource_expand_to_fit()
939  * resource discovery, and late discovery of CXL resources are expected
946  * remove_resource - Remove a resource in the resource tree
947  * @old: resource to remove
949  * Returns 0 on success, -EINVAL if the resource is not valid.
951  * This function removes a resource previously inserted by insert_resource()
954  * insert a new resource, and move any conflicting resources down to the
955  * children of the new resource.
960 int remove_resource(struct resource *old)  in remove_resource()
971 static int __adjust_resource(struct resource *res, resource_size_t start,  in __adjust_resource()
974 	struct resource *tmp, *parent = res->parent;  in __adjust_resource()
1009  * adjust_resource - modify a resource's start and size
1010  * @res: resource to modify
1014  * Given an existing resource, change its start and size to match the
1016  * Existing children of the resource are assumed to be immutable.
1018 int adjust_resource(struct resource *res, resource_size_t start,  in adjust_resource()
1031 __reserve_region_with_split(struct resource *root, resource_size_t start,  in __reserve_region_with_split()
1034 	struct resource *parent = root;  in __reserve_region_with_split()
1035 	struct resource *conflict;  in __reserve_region_with_split()
1036 	struct resource *res = alloc_resource(GFP_ATOMIC);  in __reserve_region_with_split()
1037 	struct resource *next_res = NULL;  in __reserve_region_with_split()
1092 reserve_region_with_split(struct resource *root, resource_size_t start,  in reserve_region_with_split()
1121  * resource_alignment - calculate resource's alignment
1122  * @res: resource pointer
1126 resource_size_t resource_alignment(struct resource *res)  in resource_alignment()
1154 static void revoke_iomem(struct resource *res)  in revoke_iomem()
1170 	 * the resource busy by this point, so devmem_is_allowed()  in revoke_iomem()
1172 	 * does not iterate the entire resource range.  in revoke_iomem()
1186 static void revoke_iomem(struct resource *res) {}  in revoke_iomem()
1200 static int __request_region_locked(struct resource *res, struct resource *parent,  in __request_region_locked()
1211 		struct resource *conflict;  in __request_region_locked()
1252  * __request_region - create a new busy resource region
1253  * @parent: parent resource descriptor
1254  * @start: resource start address
1255  * @n: resource region size
1257  * @flags: IO resource flags
1259 struct resource *__request_region(struct resource *parent,  in __request_region()
1263 	struct resource *res = alloc_resource(GFP_KERNEL);  in __request_region()
1286  * __release_region - release a previously reserved resource region
1287  * @parent: parent resource descriptor
1288  * @start: resource start address
1289  * @n: resource region size
1291  * The described resource region must match a currently busy region.
1293 void __release_region(struct resource *parent, resource_size_t start,  in __release_region()
1296 	struct resource **p;  in __release_region()
1305 		struct resource *res = *p;  in __release_region()
1328 	pr_warn("Trying to free nonexistent resource <%pa-%pa>\n", &start, &end);  in __release_region()
1335  * @start: resource start address
1336  * @size: resource region size
1339  * is released from a currently busy memory resource.  The requested region
1340  * must either match exactly or fit into a single busy resource entry.  In
1341  * the latter case, the remaining resource is adjusted accordingly.
1342  * Existing children of the busy memory resource must be immutable in the
1348  * - When a busy memory resource gets split into two entries, the code
1354 	struct resource *parent = &iomem_resource;  in release_mem_region_adjustable()
1355 	struct resource *new_res = NULL;  in release_mem_region_adjustable()
1357 	struct resource **p;  in release_mem_region_adjustable()
1358 	struct resource *res;  in release_mem_region_adjustable()
1382 		/* look for the next resource if it does not fit into */  in release_mem_region_adjustable()
1396 		/* found the target resource; let's adjust accordingly */  in release_mem_region_adjustable()
1410 			/* split into two entries - we need a new resource */  in release_mem_region_adjustable()
1444 static bool system_ram_resources_mergeable(struct resource *r1,  in system_ram_resources_mergeable()
1445 					   struct resource *r2)  in system_ram_resources_mergeable()
1454  * merge_system_ram_resource - mark the System RAM resource mergeable and try to
1456  * @res: resource descriptor
1460  * the actual resource boundaries are not of interest (e.g., it might be
1467  *   marked mergeable are used anymore after this call - the resource might
1471 void merge_system_ram_resource(struct resource *res)  in merge_system_ram_resource()
1474 	struct resource *cur;  in merge_system_ram_resource()
1504  * Managed region resource
1508 	struct resource **r = ptr;  in devm_resource_release()
1514  * devm_request_resource() - request and reserve an I/O or memory resource
1515  * @dev: device for which to request the resource
1516  * @root: root of the resource tree from which to request the resource
1517  * @new: descriptor of the resource to request
1522  * If for some reason the resource needs to be released explicitly, because
1527  * requested resource, an error message will be printed.
1531 int devm_request_resource(struct device *dev, struct resource *root,  in devm_request_resource()
1532 			  struct resource *new)  in devm_request_resource()
1534 	struct resource *conflict, **ptr;  in devm_request_resource()
1544 		dev_err(dev, "resource collision: %pR conflicts with %s %pR\n",  in devm_request_resource()
1557 	struct resource **ptr = res;  in devm_resource_match()
1563  * devm_release_resource() - release a previously requested resource
1564  * @dev: device for which to release the resource
1565  * @new: descriptor of the resource to release
1567  * Releases a resource previously requested using devm_request_resource().
1569 void devm_release_resource(struct device *dev, struct resource *new)  in devm_release_resource()
1577 	struct resource *parent;
1597 struct resource *
1598 __devm_request_region(struct device *dev, struct resource *parent,  in __devm_request_region()
1602 	struct resource *res;  in __devm_request_region()
1623 void __devm_release_region(struct device *dev, struct resource *parent,  in __devm_release_region()
1641 	static struct resource reserve[MAXRESERVE];  in reserve_setup()
1646 		struct resource *parent;  in reserve_setup()
1653 			struct resource *res = reserve + x;  in reserve_setup()
1682  * iomem resource tree.
1686 	struct resource *p = &iomem_resource;  in iomem_map_sanity_check()
1705 		 * if a resource is "BUSY", it's not a hardware resource  in iomem_map_sanity_check()
1706 		 * but a driver mapping of such a resource; we don't want  in iomem_map_sanity_check()
1713 		pr_warn("resource sanity check: requesting [mem %pa-%pa], which spans more than %s %pR\n",  in iomem_map_sanity_check()
1735 bool resource_is_exclusive(struct resource *root, u64 addr, resource_size_t size)  in resource_is_exclusive()
1740 	struct resource *p;  in resource_is_exclusive()
1765 		 * A resource is exclusive if IORESOURCE_EXCLUSIVE is set  in resource_is_exclusive()
1767 		 * resource is busy.  in resource_is_exclusive()
1788 struct resource_entry *resource_list_create_entry(struct resource *res,  in resource_list_create_entry()
1817 static resource_size_t gfr_start(struct resource *base, resource_size_t size,  in gfr_start()
1830 static bool gfr_continue(struct resource *base, resource_size_t addr,  in gfr_continue()
1853 	struct resource *res = _res;  in remove_free_mem_region()
1860 static struct resource *
1861 get_free_mem_region(struct device *dev, struct resource *base,  in get_free_mem_region()
1867 	struct resource *res;  in get_free_mem_region()
1925 			 * Only succeed if the resource hosts an exclusive  in get_free_mem_region()
1950  * @dev: device struct to bind the resource to
1952  * @base: resource tree to look in
1955  * contain the new resource, so that it can later be hotplugged as ZONE_DEVICE
1958 struct resource *devm_request_free_mem_region(struct device *dev,  in devm_request_free_mem_region()
1959 		struct resource *base, unsigned long size)  in devm_request_free_mem_region()
1969 struct resource *request_free_mem_region(struct resource *base,  in request_free_mem_region()
1981  * @base: resource that will parent the new resource
1984  * @name: resource name
1988  * Allocate and insert a new resource to cover a free, unclaimed by a
1991 struct resource *alloc_free_mem_region(struct resource *base,  in alloc_free_mem_region()
1995 	/* Default of ascending direction and insert resource */  in alloc_free_mem_region()