2 * linux/kernel/resource.c
4 * Copyright (C) 1999 Linus Torvalds
5 * Copyright (C) 1999 Martin Mares <mj@ucw.cz>
7 * Arbitrary resource management.
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 #include <linux/export.h>
13 #include <linux/errno.h>
14 #include <linux/ioport.h>
15 #include <linux/init.h>
16 #include <linux/slab.h>
17 #include <linux/spinlock.h>
19 #include <linux/proc_fs.h>
20 #include <linux/sched.h>
21 #include <linux/seq_file.h>
22 #include <linux/device.h>
23 #include <linux/pfn.h>
25 #include <linux/resource_ext.h>
29 struct resource ioport_resource
= {
32 .end
= IO_SPACE_LIMIT
,
33 .flags
= IORESOURCE_IO
,
35 EXPORT_SYMBOL(ioport_resource
);
37 struct resource iomem_resource
= {
41 .flags
= IORESOURCE_MEM
,
43 EXPORT_SYMBOL(iomem_resource
);
45 /* constraints to be met while allocating resources */
46 struct resource_constraint
{
47 resource_size_t min
, max
, align
;
48 resource_size_t (*alignf
)(void *, const struct resource
*,
49 resource_size_t
, resource_size_t
);
53 static DEFINE_RWLOCK(resource_lock
);
56 * For memory hotplug, there is no way to free resource entries allocated
57 * by boot mem after the system is up. So for reusing the resource entry
58 * we need to remember the resource.
60 static struct resource
*bootmem_resource_free
;
61 static DEFINE_SPINLOCK(bootmem_resource_lock
);
63 static struct resource
*next_resource(struct resource
*p
, bool sibling_only
)
65 /* Caller wants to traverse through siblings only */
71 while (!p
->sibling
&& p
->parent
)
76 static void *r_next(struct seq_file
*m
, void *v
, loff_t
*pos
)
78 struct resource
*p
= v
;
80 return (void *)next_resource(p
, false);
85 enum { MAX_IORES_LEVEL
= 5 };
87 static void *r_start(struct seq_file
*m
, loff_t
*pos
)
88 __acquires(resource_lock
)
90 struct resource
*p
= m
->private;
92 read_lock(&resource_lock
);
93 for (p
= p
->child
; p
&& l
< *pos
; p
= r_next(m
, p
, &l
))
98 static void r_stop(struct seq_file
*m
, void *v
)
99 __releases(resource_lock
)
101 read_unlock(&resource_lock
);
104 static int r_show(struct seq_file
*m
, void *v
)
106 struct resource
*root
= m
->private;
107 struct resource
*r
= v
, *p
;
108 unsigned long long start
, end
;
109 int width
= root
->end
< 0x10000 ? 4 : 8;
112 for (depth
= 0, p
= r
; depth
< MAX_IORES_LEVEL
; depth
++, p
= p
->parent
)
113 if (p
->parent
== root
)
116 if (file_ns_capable(m
->file
, &init_user_ns
, CAP_SYS_ADMIN
)) {
123 seq_printf(m
, "%*s%0*llx-%0*llx : %s\n",
127 r
->name
? r
->name
: "<BAD>");
131 static const struct seq_operations resource_op
= {
138 static int ioports_open(struct inode
*inode
, struct file
*file
)
140 int res
= seq_open(file
, &resource_op
);
142 struct seq_file
*m
= file
->private_data
;
143 m
->private = &ioport_resource
;
148 static int iomem_open(struct inode
*inode
, struct file
*file
)
150 int res
= seq_open(file
, &resource_op
);
152 struct seq_file
*m
= file
->private_data
;
153 m
->private = &iomem_resource
;
158 static const struct file_operations proc_ioports_operations
= {
159 .open
= ioports_open
,
162 .release
= seq_release
,
165 static const struct file_operations proc_iomem_operations
= {
169 .release
= seq_release
,
172 static int __init
ioresources_init(void)
174 proc_create("ioports", 0, NULL
, &proc_ioports_operations
);
175 proc_create("iomem", 0, NULL
, &proc_iomem_operations
);
178 __initcall(ioresources_init
);
180 #endif /* CONFIG_PROC_FS */
182 static void free_resource(struct resource
*res
)
187 if (!PageSlab(virt_to_head_page(res
))) {
188 spin_lock(&bootmem_resource_lock
);
189 res
->sibling
= bootmem_resource_free
;
190 bootmem_resource_free
= res
;
191 spin_unlock(&bootmem_resource_lock
);
197 static struct resource
*alloc_resource(gfp_t flags
)
199 struct resource
*res
= NULL
;
201 spin_lock(&bootmem_resource_lock
);
202 if (bootmem_resource_free
) {
203 res
= bootmem_resource_free
;
204 bootmem_resource_free
= res
->sibling
;
206 spin_unlock(&bootmem_resource_lock
);
209 memset(res
, 0, sizeof(struct resource
));
211 res
= kzalloc(sizeof(struct resource
), flags
);
216 /* Return the conflict entry if you can't request it */
217 static struct resource
* __request_resource(struct resource
*root
, struct resource
*new)
219 resource_size_t start
= new->start
;
220 resource_size_t end
= new->end
;
221 struct resource
*tmp
, **p
;
225 if (start
< root
->start
)
232 if (!tmp
|| tmp
->start
> end
) {
239 if (tmp
->end
< start
)
245 static int __release_resource(struct resource
*old
, bool release_child
)
247 struct resource
*tmp
, **p
, *chd
;
250 WARN(old
->sibling
, "sibling but no parent");
255 p
= &old
->parent
->child
;
261 if (release_child
|| !(tmp
->child
)) {
264 for (chd
= tmp
->child
;; chd
= chd
->sibling
) {
265 chd
->parent
= tmp
->parent
;
270 chd
->sibling
= tmp
->sibling
;
280 static void __release_child_resources(struct resource
*r
)
282 struct resource
*tmp
, *p
;
283 resource_size_t size
;
293 __release_child_resources(tmp
);
295 printk(KERN_DEBUG
"release child resource %pR\n", tmp
);
296 /* need to restore size, and keep flags */
297 size
= resource_size(tmp
);
303 void release_child_resources(struct resource
*r
)
305 write_lock(&resource_lock
);
306 __release_child_resources(r
);
307 write_unlock(&resource_lock
);
311 * request_resource_conflict - request and reserve an I/O or memory resource
312 * @root: root resource descriptor
313 * @new: resource descriptor desired by caller
315 * Returns 0 for success, conflict resource on error.
317 struct resource
*request_resource_conflict(struct resource
*root
, struct resource
*new)
319 struct resource
*conflict
;
321 write_lock(&resource_lock
);
322 conflict
= __request_resource(root
, new);
323 write_unlock(&resource_lock
);
328 * request_resource - request and reserve an I/O or memory resource
329 * @root: root resource descriptor
330 * @new: resource descriptor desired by caller
332 * Returns 0 for success, negative error code on error.
334 int request_resource(struct resource
*root
, struct resource
*new)
336 struct resource
*conflict
;
338 conflict
= request_resource_conflict(root
, new);
339 return conflict
? -EBUSY
: 0;
342 EXPORT_SYMBOL(request_resource
);
345 * release_resource - release a previously reserved resource
346 * @old: resource pointer
348 int release_resource(struct resource
*old
)
352 write_lock(&resource_lock
);
353 retval
= __release_resource(old
, true);
354 write_unlock(&resource_lock
);
358 EXPORT_SYMBOL(release_resource
);
361 * Finds the lowest iomem resource existing within [res->start.res->end).
362 * The caller must specify res->start, res->end, res->flags, and optionally
363 * desc. If found, returns 0, res is overwritten, if not found, returns -1.
364 * This function walks the whole tree and not just first level children until
365 * and unless first_level_children_only is true.
367 static int find_next_iomem_res(struct resource
*res
, unsigned long desc
,
368 bool first_level_children_only
)
370 resource_size_t start
, end
;
372 bool sibling_only
= false;
378 BUG_ON(start
>= end
);
380 if (first_level_children_only
)
383 read_lock(&resource_lock
);
385 for (p
= iomem_resource
.child
; p
; p
= next_resource(p
, sibling_only
)) {
386 if ((p
->flags
& res
->flags
) != res
->flags
)
388 if ((desc
!= IORES_DESC_NONE
) && (desc
!= p
->desc
))
390 if (p
->start
> end
) {
394 if ((p
->end
>= start
) && (p
->start
< end
))
398 read_unlock(&resource_lock
);
402 if (res
->start
< p
->start
)
403 res
->start
= p
->start
;
404 if (res
->end
> p
->end
)
410 * Walks through iomem resources and calls func() with matching resource
411 * ranges. This walks through whole tree and not just first level children.
412 * All the memory ranges which overlap start,end and also match flags and
413 * desc are valid candidates.
415 * @desc: I/O resource descriptor. Use IORES_DESC_NONE to skip @desc check.
416 * @flags: I/O resource flags
420 * NOTE: For a new descriptor search, define a new IORES_DESC in
421 * <linux/ioport.h> and set it in 'desc' of a target resource entry.
423 int walk_iomem_res_desc(unsigned long desc
, unsigned long flags
, u64 start
,
424 u64 end
, void *arg
, int (*func
)(u64
, u64
, void *))
435 while ((res
.start
< res
.end
) &&
436 (!find_next_iomem_res(&res
, desc
, false))) {
438 ret
= (*func
)(res
.start
, res
.end
, arg
);
442 res
.start
= res
.end
+ 1;
450 * This function calls the @func callback against all memory ranges of type
451 * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY.
452 * Now, this function is only for System RAM, it deals with full ranges and
453 * not PFNs. If resources are not PFN-aligned, dealing with PFNs can truncate
456 int walk_system_ram_res(u64 start
, u64 end
, void *arg
,
457 int (*func
)(u64
, u64
, void *))
465 res
.flags
= IORESOURCE_SYSTEM_RAM
| IORESOURCE_BUSY
;
467 while ((res
.start
< res
.end
) &&
468 (!find_next_iomem_res(&res
, IORES_DESC_NONE
, true))) {
469 ret
= (*func
)(res
.start
, res
.end
, arg
);
472 res
.start
= res
.end
+ 1;
478 #if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
481 * This function calls the @func callback against all memory ranges of type
482 * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY.
483 * It is to be used only for System RAM.
485 int walk_system_ram_range(unsigned long start_pfn
, unsigned long nr_pages
,
486 void *arg
, int (*func
)(unsigned long, unsigned long, void *))
489 unsigned long pfn
, end_pfn
;
493 res
.start
= (u64
) start_pfn
<< PAGE_SHIFT
;
494 res
.end
= ((u64
)(start_pfn
+ nr_pages
) << PAGE_SHIFT
) - 1;
495 res
.flags
= IORESOURCE_SYSTEM_RAM
| IORESOURCE_BUSY
;
497 while ((res
.start
< res
.end
) &&
498 (find_next_iomem_res(&res
, IORES_DESC_NONE
, true) >= 0)) {
499 pfn
= (res
.start
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
500 end_pfn
= (res
.end
+ 1) >> PAGE_SHIFT
;
502 ret
= (*func
)(pfn
, end_pfn
- pfn
, arg
);
505 res
.start
= res
.end
+ 1;
513 static int __is_ram(unsigned long pfn
, unsigned long nr_pages
, void *arg
)
518 * This generic page_is_ram() returns true if specified address is
519 * registered as System RAM in iomem_resource list.
521 int __weak
page_is_ram(unsigned long pfn
)
523 return walk_system_ram_range(pfn
, 1, NULL
, __is_ram
) == 1;
525 EXPORT_SYMBOL_GPL(page_is_ram
);
528 * region_intersects() - determine intersection of region with known resources
529 * @start: region start address
530 * @size: size of region
531 * @flags: flags of resource (in iomem_resource)
532 * @desc: descriptor of resource (in iomem_resource) or IORES_DESC_NONE
534 * Check if the specified region partially overlaps or fully eclipses a
535 * resource identified by @flags and @desc (optional with IORES_DESC_NONE).
536 * Return REGION_DISJOINT if the region does not overlap @flags/@desc,
537 * return REGION_MIXED if the region overlaps @flags/@desc and another
538 * resource, and return REGION_INTERSECTS if the region overlaps @flags/@desc
539 * and no other defined resource. Note that REGION_INTERSECTS is also
540 * returned in the case when the specified region overlaps RAM and undefined
543 * region_intersect() is used by memory remapping functions to ensure
544 * the user is not remapping RAM and is a vast speed up over walking
545 * through the resource table page by page.
547 int region_intersects(resource_size_t start
, size_t size
, unsigned long flags
,
550 resource_size_t end
= start
+ size
- 1;
551 int type
= 0; int other
= 0;
554 read_lock(&resource_lock
);
555 for (p
= iomem_resource
.child
; p
; p
= p
->sibling
) {
556 bool is_type
= (((p
->flags
& flags
) == flags
) &&
557 ((desc
== IORES_DESC_NONE
) ||
560 if (start
>= p
->start
&& start
<= p
->end
)
561 is_type
? type
++ : other
++;
562 if (end
>= p
->start
&& end
<= p
->end
)
563 is_type
? type
++ : other
++;
564 if (p
->start
>= start
&& p
->end
<= end
)
565 is_type
? type
++ : other
++;
567 read_unlock(&resource_lock
);
570 return type
? REGION_INTERSECTS
: REGION_DISJOINT
;
575 return REGION_DISJOINT
;
577 EXPORT_SYMBOL_GPL(region_intersects
);
579 void __weak
arch_remove_reservations(struct resource
*avail
)
583 static resource_size_t
simple_align_resource(void *data
,
584 const struct resource
*avail
,
585 resource_size_t size
,
586 resource_size_t align
)
591 static void resource_clip(struct resource
*res
, resource_size_t min
,
594 if (res
->start
< min
)
601 * Find empty slot in the resource tree with the given range and
602 * alignment constraints
604 static int __find_resource(struct resource
*root
, struct resource
*old
,
605 struct resource
*new,
606 resource_size_t size
,
607 struct resource_constraint
*constraint
)
609 struct resource
*this = root
->child
;
610 struct resource tmp
= *new, avail
, alloc
;
612 tmp
.start
= root
->start
;
614 * Skip past an allocated resource that starts at 0, since the assignment
615 * of this->start - 1 to tmp->end below would cause an underflow.
617 if (this && this->start
== root
->start
) {
618 tmp
.start
= (this == old
) ? old
->start
: this->end
+ 1;
619 this = this->sibling
;
623 tmp
.end
= (this == old
) ? this->end
: this->start
- 1;
627 if (tmp
.end
< tmp
.start
)
630 resource_clip(&tmp
, constraint
->min
, constraint
->max
);
631 arch_remove_reservations(&tmp
);
633 /* Check for overflow after ALIGN() */
634 avail
.start
= ALIGN(tmp
.start
, constraint
->align
);
636 avail
.flags
= new->flags
& ~IORESOURCE_UNSET
;
637 if (avail
.start
>= tmp
.start
) {
638 alloc
.flags
= avail
.flags
;
639 alloc
.start
= constraint
->alignf(constraint
->alignf_data
, &avail
,
640 size
, constraint
->align
);
641 alloc
.end
= alloc
.start
+ size
- 1;
642 if (resource_contains(&avail
, &alloc
)) {
643 new->start
= alloc
.start
;
644 new->end
= alloc
.end
;
649 next
: if (!this || this->end
== root
->end
)
653 tmp
.start
= this->end
+ 1;
654 this = this->sibling
;
660 * Find empty slot in the resource tree given range and alignment.
662 static int find_resource(struct resource
*root
, struct resource
*new,
663 resource_size_t size
,
664 struct resource_constraint
*constraint
)
666 return __find_resource(root
, NULL
, new, size
, constraint
);
670 * reallocate_resource - allocate a slot in the resource tree given range & alignment.
671 * The resource will be relocated if the new size cannot be reallocated in the
674 * @root: root resource descriptor
675 * @old: resource descriptor desired by caller
676 * @newsize: new size of the resource descriptor
677 * @constraint: the size and alignment constraints to be met.
679 static int reallocate_resource(struct resource
*root
, struct resource
*old
,
680 resource_size_t newsize
,
681 struct resource_constraint
*constraint
)
684 struct resource
new = *old
;
685 struct resource
*conflict
;
687 write_lock(&resource_lock
);
689 if ((err
= __find_resource(root
, old
, &new, newsize
, constraint
)))
692 if (resource_contains(&new, old
)) {
693 old
->start
= new.start
;
703 if (resource_contains(old
, &new)) {
704 old
->start
= new.start
;
707 __release_resource(old
, true);
709 conflict
= __request_resource(root
, old
);
713 write_unlock(&resource_lock
);
719 * allocate_resource - allocate empty slot in the resource tree given range & alignment.
720 * The resource will be reallocated with a new size if it was already allocated
721 * @root: root resource descriptor
722 * @new: resource descriptor desired by caller
723 * @size: requested resource region size
724 * @min: minimum boundary to allocate
725 * @max: maximum boundary to allocate
726 * @align: alignment requested, in bytes
727 * @alignf: alignment function, optional, called if not NULL
728 * @alignf_data: arbitrary data to pass to the @alignf function
730 int allocate_resource(struct resource
*root
, struct resource
*new,
731 resource_size_t size
, resource_size_t min
,
732 resource_size_t max
, resource_size_t align
,
733 resource_size_t (*alignf
)(void *,
734 const struct resource
*,
740 struct resource_constraint constraint
;
743 alignf
= simple_align_resource
;
745 constraint
.min
= min
;
746 constraint
.max
= max
;
747 constraint
.align
= align
;
748 constraint
.alignf
= alignf
;
749 constraint
.alignf_data
= alignf_data
;
752 /* resource is already allocated, try reallocating with
753 the new constraints */
754 return reallocate_resource(root
, new, size
, &constraint
);
757 write_lock(&resource_lock
);
758 err
= find_resource(root
, new, size
, &constraint
);
759 if (err
>= 0 && __request_resource(root
, new))
761 write_unlock(&resource_lock
);
765 EXPORT_SYMBOL(allocate_resource
);
768 * lookup_resource - find an existing resource by a resource start address
769 * @root: root resource descriptor
770 * @start: resource start address
772 * Returns a pointer to the resource if found, NULL otherwise
774 struct resource
*lookup_resource(struct resource
*root
, resource_size_t start
)
776 struct resource
*res
;
778 read_lock(&resource_lock
);
779 for (res
= root
->child
; res
; res
= res
->sibling
) {
780 if (res
->start
== start
)
783 read_unlock(&resource_lock
);
789 * Insert a resource into the resource tree. If successful, return NULL,
790 * otherwise return the conflicting resource (compare to __request_resource())
792 static struct resource
* __insert_resource(struct resource
*parent
, struct resource
*new)
794 struct resource
*first
, *next
;
796 for (;; parent
= first
) {
797 first
= __request_resource(parent
, new);
803 if (WARN_ON(first
== new)) /* duplicated insertion */
806 if ((first
->start
> new->start
) || (first
->end
< new->end
))
808 if ((first
->start
== new->start
) && (first
->end
== new->end
))
812 for (next
= first
; ; next
= next
->sibling
) {
813 /* Partial overlap? Bad, and unfixable */
814 if (next
->start
< new->start
|| next
->end
> new->end
)
818 if (next
->sibling
->start
> new->end
)
822 new->parent
= parent
;
823 new->sibling
= next
->sibling
;
826 next
->sibling
= NULL
;
827 for (next
= first
; next
; next
= next
->sibling
)
830 if (parent
->child
== first
) {
833 next
= parent
->child
;
834 while (next
->sibling
!= first
)
835 next
= next
->sibling
;
842 * insert_resource_conflict - Inserts resource in the resource tree
843 * @parent: parent of the new resource
844 * @new: new resource to insert
846 * Returns 0 on success, conflict resource if the resource can't be inserted.
848 * This function is equivalent to request_resource_conflict when no conflict
849 * happens. If a conflict happens, and the conflicting resources
850 * entirely fit within the range of the new resource, then the new
851 * resource is inserted and the conflicting resources become children of
854 * This function is intended for producers of resources, such as FW modules
857 struct resource
*insert_resource_conflict(struct resource
*parent
, struct resource
*new)
859 struct resource
*conflict
;
861 write_lock(&resource_lock
);
862 conflict
= __insert_resource(parent
, new);
863 write_unlock(&resource_lock
);
868 * insert_resource - Inserts a resource in the resource tree
869 * @parent: parent of the new resource
870 * @new: new resource to insert
872 * Returns 0 on success, -EBUSY if the resource can't be inserted.
874 * This function is intended for producers of resources, such as FW modules
877 int insert_resource(struct resource
*parent
, struct resource
*new)
879 struct resource
*conflict
;
881 conflict
= insert_resource_conflict(parent
, new);
882 return conflict
? -EBUSY
: 0;
884 EXPORT_SYMBOL_GPL(insert_resource
);
887 * insert_resource_expand_to_fit - Insert a resource into the resource tree
888 * @root: root resource descriptor
889 * @new: new resource to insert
891 * Insert a resource into the resource tree, possibly expanding it in order
892 * to make it encompass any conflicting resources.
894 void insert_resource_expand_to_fit(struct resource
*root
, struct resource
*new)
899 write_lock(&resource_lock
);
901 struct resource
*conflict
;
903 conflict
= __insert_resource(root
, new);
906 if (conflict
== root
)
909 /* Ok, expand resource to cover the conflict, then try again .. */
910 if (conflict
->start
< new->start
)
911 new->start
= conflict
->start
;
912 if (conflict
->end
> new->end
)
913 new->end
= conflict
->end
;
915 printk("Expanded resource %s due to conflict with %s\n", new->name
, conflict
->name
);
917 write_unlock(&resource_lock
);
921 * remove_resource - Remove a resource in the resource tree
922 * @old: resource to remove
924 * Returns 0 on success, -EINVAL if the resource is not valid.
926 * This function removes a resource previously inserted by insert_resource()
927 * or insert_resource_conflict(), and moves the children (if any) up to
928 * where they were before. insert_resource() and insert_resource_conflict()
929 * insert a new resource, and move any conflicting resources down to the
930 * children of the new resource.
932 * insert_resource(), insert_resource_conflict() and remove_resource() are
933 * intended for producers of resources, such as FW modules and bus drivers.
935 int remove_resource(struct resource
*old
)
939 write_lock(&resource_lock
);
940 retval
= __release_resource(old
, false);
941 write_unlock(&resource_lock
);
944 EXPORT_SYMBOL_GPL(remove_resource
);
946 static int __adjust_resource(struct resource
*res
, resource_size_t start
,
947 resource_size_t size
)
949 struct resource
*tmp
, *parent
= res
->parent
;
950 resource_size_t end
= start
+ size
- 1;
956 if ((start
< parent
->start
) || (end
> parent
->end
))
959 if (res
->sibling
&& (res
->sibling
->start
<= end
))
964 while (tmp
->sibling
!= res
)
966 if (start
<= tmp
->end
)
971 for (tmp
= res
->child
; tmp
; tmp
= tmp
->sibling
)
972 if ((tmp
->start
< start
) || (tmp
->end
> end
))
984 * adjust_resource - modify a resource's start and size
985 * @res: resource to modify
986 * @start: new start value
989 * Given an existing resource, change its start and size to match the
990 * arguments. Returns 0 on success, -EBUSY if it can't fit.
991 * Existing children of the resource are assumed to be immutable.
993 int adjust_resource(struct resource
*res
, resource_size_t start
,
994 resource_size_t size
)
998 write_lock(&resource_lock
);
999 result
= __adjust_resource(res
, start
, size
);
1000 write_unlock(&resource_lock
);
1003 EXPORT_SYMBOL(adjust_resource
);
1005 static void __init
__reserve_region_with_split(struct resource
*root
,
1006 resource_size_t start
, resource_size_t end
,
1009 struct resource
*parent
= root
;
1010 struct resource
*conflict
;
1011 struct resource
*res
= alloc_resource(GFP_ATOMIC
);
1012 struct resource
*next_res
= NULL
;
1020 res
->flags
= IORESOURCE_BUSY
;
1021 res
->desc
= IORES_DESC_NONE
;
1025 conflict
= __request_resource(parent
, res
);
1034 /* conflict covered whole area */
1035 if (conflict
->start
<= res
->start
&&
1036 conflict
->end
>= res
->end
) {
1042 /* failed, split and try again */
1043 if (conflict
->start
> res
->start
) {
1045 res
->end
= conflict
->start
- 1;
1046 if (conflict
->end
< end
) {
1047 next_res
= alloc_resource(GFP_ATOMIC
);
1052 next_res
->name
= name
;
1053 next_res
->start
= conflict
->end
+ 1;
1054 next_res
->end
= end
;
1055 next_res
->flags
= IORESOURCE_BUSY
;
1056 next_res
->desc
= IORES_DESC_NONE
;
1059 res
->start
= conflict
->end
+ 1;
1065 void __init
reserve_region_with_split(struct resource
*root
,
1066 resource_size_t start
, resource_size_t end
,
1071 write_lock(&resource_lock
);
1072 if (root
->start
> start
|| root
->end
< end
) {
1073 pr_err("requested range [0x%llx-0x%llx] not in root %pr\n",
1074 (unsigned long long)start
, (unsigned long long)end
,
1076 if (start
> root
->end
|| end
< root
->start
)
1079 if (end
> root
->end
)
1081 if (start
< root
->start
)
1082 start
= root
->start
;
1083 pr_err("fixing request to [0x%llx-0x%llx]\n",
1084 (unsigned long long)start
,
1085 (unsigned long long)end
);
1090 __reserve_region_with_split(root
, start
, end
, name
);
1091 write_unlock(&resource_lock
);
1095 * resource_alignment - calculate resource's alignment
1096 * @res: resource pointer
1098 * Returns alignment on success, 0 (invalid alignment) on failure.
1100 resource_size_t
resource_alignment(struct resource
*res
)
1102 switch (res
->flags
& (IORESOURCE_SIZEALIGN
| IORESOURCE_STARTALIGN
)) {
1103 case IORESOURCE_SIZEALIGN
:
1104 return resource_size(res
);
1105 case IORESOURCE_STARTALIGN
:
1113 * This is compatibility stuff for IO resources.
1115 * Note how this, unlike the above, knows about
1116 * the IO flag meanings (busy etc).
1118 * request_region creates a new busy region.
1120 * release_region releases a matching busy region.
1123 static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait
);
1126 * __request_region - create a new busy resource region
1127 * @parent: parent resource descriptor
1128 * @start: resource start address
1129 * @n: resource region size
1130 * @name: reserving caller's ID string
1131 * @flags: IO resource flags
1133 struct resource
* __request_region(struct resource
*parent
,
1134 resource_size_t start
, resource_size_t n
,
1135 const char *name
, int flags
)
1137 DECLARE_WAITQUEUE(wait
, current
);
1138 struct resource
*res
= alloc_resource(GFP_KERNEL
);
1145 res
->end
= start
+ n
- 1;
1147 write_lock(&resource_lock
);
1150 struct resource
*conflict
;
1152 res
->flags
= resource_type(parent
) | resource_ext_type(parent
);
1153 res
->flags
|= IORESOURCE_BUSY
| flags
;
1154 res
->desc
= parent
->desc
;
1156 conflict
= __request_resource(parent
, res
);
1159 if (conflict
!= parent
) {
1160 if (!(conflict
->flags
& IORESOURCE_BUSY
)) {
1165 if (conflict
->flags
& flags
& IORESOURCE_MUXED
) {
1166 add_wait_queue(&muxed_resource_wait
, &wait
);
1167 write_unlock(&resource_lock
);
1168 set_current_state(TASK_UNINTERRUPTIBLE
);
1170 remove_wait_queue(&muxed_resource_wait
, &wait
);
1171 write_lock(&resource_lock
);
1174 /* Uhhuh, that didn't work out.. */
1179 write_unlock(&resource_lock
);
1182 EXPORT_SYMBOL(__request_region
);
1185 * __release_region - release a previously reserved resource region
1186 * @parent: parent resource descriptor
1187 * @start: resource start address
1188 * @n: resource region size
1190 * The described resource region must match a currently busy region.
1192 void __release_region(struct resource
*parent
, resource_size_t start
,
1195 struct resource
**p
;
1196 resource_size_t end
;
1199 end
= start
+ n
- 1;
1201 write_lock(&resource_lock
);
1204 struct resource
*res
= *p
;
1208 if (res
->start
<= start
&& res
->end
>= end
) {
1209 if (!(res
->flags
& IORESOURCE_BUSY
)) {
1213 if (res
->start
!= start
|| res
->end
!= end
)
1216 write_unlock(&resource_lock
);
1217 if (res
->flags
& IORESOURCE_MUXED
)
1218 wake_up(&muxed_resource_wait
);
1225 write_unlock(&resource_lock
);
1227 printk(KERN_WARNING
"Trying to free nonexistent resource "
1228 "<%016llx-%016llx>\n", (unsigned long long)start
,
1229 (unsigned long long)end
);
1231 EXPORT_SYMBOL(__release_region
);
1233 #ifdef CONFIG_MEMORY_HOTREMOVE
1235 * release_mem_region_adjustable - release a previously reserved memory region
1236 * @parent: parent resource descriptor
1237 * @start: resource start address
1238 * @size: resource region size
1240 * This interface is intended for memory hot-delete. The requested region
1241 * is released from a currently busy memory resource. The requested region
1242 * must either match exactly or fit into a single busy resource entry. In
1243 * the latter case, the remaining resource is adjusted accordingly.
1244 * Existing children of the busy memory resource must be immutable in the
1248 * - Additional release conditions, such as overlapping region, can be
1249 * supported after they are confirmed as valid cases.
1250 * - When a busy memory resource gets split into two entries, the code
1251 * assumes that all children remain in the lower address entry for
1252 * simplicity. Enhance this logic when necessary.
1254 int release_mem_region_adjustable(struct resource
*parent
,
1255 resource_size_t start
, resource_size_t size
)
1257 struct resource
**p
;
1258 struct resource
*res
;
1259 struct resource
*new_res
;
1260 resource_size_t end
;
1263 end
= start
+ size
- 1;
1264 if ((start
< parent
->start
) || (end
> parent
->end
))
1267 /* The alloc_resource() result gets checked later */
1268 new_res
= alloc_resource(GFP_KERNEL
);
1271 write_lock(&resource_lock
);
1273 while ((res
= *p
)) {
1274 if (res
->start
>= end
)
1277 /* look for the next resource if it does not fit into */
1278 if (res
->start
> start
|| res
->end
< end
) {
1283 if (!(res
->flags
& IORESOURCE_MEM
))
1286 if (!(res
->flags
& IORESOURCE_BUSY
)) {
1291 /* found the target resource; let's adjust accordingly */
1292 if (res
->start
== start
&& res
->end
== end
) {
1293 /* free the whole entry */
1297 } else if (res
->start
== start
&& res
->end
!= end
) {
1298 /* adjust the start */
1299 ret
= __adjust_resource(res
, end
+ 1,
1301 } else if (res
->start
!= start
&& res
->end
== end
) {
1302 /* adjust the end */
1303 ret
= __adjust_resource(res
, res
->start
,
1304 start
- res
->start
);
1306 /* split into two entries */
1311 new_res
->name
= res
->name
;
1312 new_res
->start
= end
+ 1;
1313 new_res
->end
= res
->end
;
1314 new_res
->flags
= res
->flags
;
1315 new_res
->desc
= res
->desc
;
1316 new_res
->parent
= res
->parent
;
1317 new_res
->sibling
= res
->sibling
;
1318 new_res
->child
= NULL
;
1320 ret
= __adjust_resource(res
, res
->start
,
1321 start
- res
->start
);
1324 res
->sibling
= new_res
;
1331 write_unlock(&resource_lock
);
1332 free_resource(new_res
);
1335 #endif /* CONFIG_MEMORY_HOTREMOVE */
1338 * Managed region resource
1340 static void devm_resource_release(struct device
*dev
, void *ptr
)
1342 struct resource
**r
= ptr
;
1344 release_resource(*r
);
1348 * devm_request_resource() - request and reserve an I/O or memory resource
1349 * @dev: device for which to request the resource
1350 * @root: root of the resource tree from which to request the resource
1351 * @new: descriptor of the resource to request
1353 * This is a device-managed version of request_resource(). There is usually
1354 * no need to release resources requested by this function explicitly since
1355 * that will be taken care of when the device is unbound from its driver.
1356 * If for some reason the resource needs to be released explicitly, because
1357 * of ordering issues for example, drivers must call devm_release_resource()
1358 * rather than the regular release_resource().
1360 * When a conflict is detected between any existing resources and the newly
1361 * requested resource, an error message will be printed.
1363 * Returns 0 on success or a negative error code on failure.
1365 int devm_request_resource(struct device
*dev
, struct resource
*root
,
1366 struct resource
*new)
1368 struct resource
*conflict
, **ptr
;
1370 ptr
= devres_alloc(devm_resource_release
, sizeof(*ptr
), GFP_KERNEL
);
1376 conflict
= request_resource_conflict(root
, new);
1378 dev_err(dev
, "resource collision: %pR conflicts with %s %pR\n",
1379 new, conflict
->name
, conflict
);
1384 devres_add(dev
, ptr
);
1387 EXPORT_SYMBOL(devm_request_resource
);
1389 static int devm_resource_match(struct device
*dev
, void *res
, void *data
)
1391 struct resource
**ptr
= res
;
1393 return *ptr
== data
;
1397 * devm_release_resource() - release a previously requested resource
1398 * @dev: device for which to release the resource
1399 * @new: descriptor of the resource to release
1401 * Releases a resource previously requested using devm_request_resource().
1403 void devm_release_resource(struct device
*dev
, struct resource
*new)
1405 WARN_ON(devres_release(dev
, devm_resource_release
, devm_resource_match
,
1408 EXPORT_SYMBOL(devm_release_resource
);
1410 struct region_devres
{
1411 struct resource
*parent
;
1412 resource_size_t start
;
1416 static void devm_region_release(struct device
*dev
, void *res
)
1418 struct region_devres
*this = res
;
1420 __release_region(this->parent
, this->start
, this->n
);
1423 static int devm_region_match(struct device
*dev
, void *res
, void *match_data
)
1425 struct region_devres
*this = res
, *match
= match_data
;
1427 return this->parent
== match
->parent
&&
1428 this->start
== match
->start
&& this->n
== match
->n
;
1431 struct resource
* __devm_request_region(struct device
*dev
,
1432 struct resource
*parent
, resource_size_t start
,
1433 resource_size_t n
, const char *name
)
1435 struct region_devres
*dr
= NULL
;
1436 struct resource
*res
;
1438 dr
= devres_alloc(devm_region_release
, sizeof(struct region_devres
),
1443 dr
->parent
= parent
;
1447 res
= __request_region(parent
, start
, n
, name
, 0);
1449 devres_add(dev
, dr
);
1455 EXPORT_SYMBOL(__devm_request_region
);
1457 void __devm_release_region(struct device
*dev
, struct resource
*parent
,
1458 resource_size_t start
, resource_size_t n
)
1460 struct region_devres match_data
= { parent
, start
, n
};
1462 __release_region(parent
, start
, n
);
1463 WARN_ON(devres_destroy(dev
, devm_region_release
, devm_region_match
,
1466 EXPORT_SYMBOL(__devm_release_region
);
1469 * Called from init/main.c to reserve IO ports.
1471 #define MAXRESERVE 4
1472 static int __init
reserve_setup(char *str
)
1474 static int reserved
;
1475 static struct resource reserve
[MAXRESERVE
];
1478 unsigned int io_start
, io_num
;
1481 if (get_option (&str
, &io_start
) != 2)
1483 if (get_option (&str
, &io_num
) == 0)
1485 if (x
< MAXRESERVE
) {
1486 struct resource
*res
= reserve
+ x
;
1487 res
->name
= "reserved";
1488 res
->start
= io_start
;
1489 res
->end
= io_start
+ io_num
- 1;
1490 res
->flags
= IORESOURCE_BUSY
;
1491 res
->desc
= IORES_DESC_NONE
;
1493 if (request_resource(res
->start
>= 0x10000 ? &iomem_resource
: &ioport_resource
, res
) == 0)
1500 __setup("reserve=", reserve_setup
);
1503 * Check if the requested addr and size spans more than any slot in the
1504 * iomem resource tree.
1506 int iomem_map_sanity_check(resource_size_t addr
, unsigned long size
)
1508 struct resource
*p
= &iomem_resource
;
1512 read_lock(&resource_lock
);
1513 for (p
= p
->child
; p
; p
= r_next(NULL
, p
, &l
)) {
1515 * We can probably skip the resources without
1516 * IORESOURCE_IO attribute?
1518 if (p
->start
>= addr
+ size
)
1522 if (PFN_DOWN(p
->start
) <= PFN_DOWN(addr
) &&
1523 PFN_DOWN(p
->end
) >= PFN_DOWN(addr
+ size
- 1))
1526 * if a resource is "BUSY", it's not a hardware resource
1527 * but a driver mapping of such a resource; we don't want
1528 * to warn for those; some drivers legitimately map only
1529 * partial hardware resources. (example: vesafb)
1531 if (p
->flags
& IORESOURCE_BUSY
)
1534 printk(KERN_WARNING
"resource sanity check: requesting [mem %#010llx-%#010llx], which spans more than %s %pR\n",
1535 (unsigned long long)addr
,
1536 (unsigned long long)(addr
+ size
- 1),
1541 read_unlock(&resource_lock
);
1546 #ifdef CONFIG_STRICT_DEVMEM
1547 static int strict_iomem_checks
= 1;
1549 static int strict_iomem_checks
;
1553 * check if an address is reserved in the iomem resource tree
1554 * returns 1 if reserved, 0 if not reserved.
1556 int iomem_is_exclusive(u64 addr
)
1558 struct resource
*p
= &iomem_resource
;
1561 int size
= PAGE_SIZE
;
1563 if (!strict_iomem_checks
)
1566 addr
= addr
& PAGE_MASK
;
1568 read_lock(&resource_lock
);
1569 for (p
= p
->child
; p
; p
= r_next(NULL
, p
, &l
)) {
1571 * We can probably skip the resources without
1572 * IORESOURCE_IO attribute?
1574 if (p
->start
>= addr
+ size
)
1579 * A resource is exclusive if IORESOURCE_EXCLUSIVE is set
1580 * or CONFIG_IO_STRICT_DEVMEM is enabled and the
1583 if ((p
->flags
& IORESOURCE_BUSY
) == 0)
1585 if (IS_ENABLED(CONFIG_IO_STRICT_DEVMEM
)
1586 || p
->flags
& IORESOURCE_EXCLUSIVE
) {
1591 read_unlock(&resource_lock
);
1596 struct resource_entry
*resource_list_create_entry(struct resource
*res
,
1599 struct resource_entry
*entry
;
1601 entry
= kzalloc(sizeof(*entry
) + extra_size
, GFP_KERNEL
);
1603 INIT_LIST_HEAD(&entry
->node
);
1604 entry
->res
= res
? res
: &entry
->__res
;
1609 EXPORT_SYMBOL(resource_list_create_entry
);
1611 void resource_list_free(struct list_head
*head
)
1613 struct resource_entry
*entry
, *tmp
;
1615 list_for_each_entry_safe(entry
, tmp
, head
, node
)
1616 resource_list_destroy_entry(entry
);
1618 EXPORT_SYMBOL(resource_list_free
);
1620 static int __init
strict_iomem(char *str
)
1622 if (strstr(str
, "relaxed"))
1623 strict_iomem_checks
= 0;
1624 if (strstr(str
, "strict"))
1625 strict_iomem_checks
= 1;
1629 __setup("iomem=", strict_iomem
);