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- /*
- * linux/kernel/resource.c
- *
- * Copyright (C) 1999 Linus Torvalds
- * Copyright (C) 1999 Martin Mares <mj@ucw.cz>
- *
- * Arbitrary resource management.
- */
- #include <linux/module.h>
- #include <linux/errno.h>
- #include <linux/ioport.h>
- #include <linux/init.h>
- #include <linux/slab.h>
- #include <linux/spinlock.h>
- #include <linux/fs.h>
- #include <linux/proc_fs.h>
- #include <linux/sched.h>
- #include <linux/seq_file.h>
- #include <linux/device.h>
- #include <linux/pfn.h>
- #include <asm/io.h>
- struct resource ioport_resource = {
- .name = "PCI IO",
- .start = 0,
- .end = IO_SPACE_LIMIT,
- .flags = IORESOURCE_IO,
- };
- EXPORT_SYMBOL(ioport_resource);
- struct resource iomem_resource = {
- .name = "PCI mem",
- .start = 0,
- .end = -1,
- .flags = IORESOURCE_MEM,
- };
- EXPORT_SYMBOL(iomem_resource);
- /* constraints to be met while allocating resources */
- struct resource_constraint {
- resource_size_t min, max, align;
- resource_size_t (*alignf)(void *, const struct resource *,
- resource_size_t, resource_size_t);
- void *alignf_data;
- };
- static DEFINE_RWLOCK(resource_lock);
- static void *r_next(struct seq_file *m, void *v, loff_t *pos)
- {
- struct resource *p = v;
- (*pos)++;
- if (p->child)
- return p->child;
- while (!p->sibling && p->parent)
- p = p->parent;
- return p->sibling;
- }
- #ifdef CONFIG_PROC_FS
- enum { MAX_IORES_LEVEL = 5 };
- static void *r_start(struct seq_file *m, loff_t *pos)
- __acquires(resource_lock)
- {
- struct resource *p = m->private;
- loff_t l = 0;
- read_lock(&resource_lock);
- for (p = p->child; p && l < *pos; p = r_next(m, p, &l))
- ;
- return p;
- }
- static void r_stop(struct seq_file *m, void *v)
- __releases(resource_lock)
- {
- read_unlock(&resource_lock);
- }
- static int r_show(struct seq_file *m, void *v)
- {
- struct resource *root = m->private;
- struct resource *r = v, *p;
- int width = root->end < 0x10000 ? 4 : 8;
- int depth;
- for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent)
- if (p->parent == root)
- break;
- seq_printf(m, "%*s%0*llx-%0*llx : %s\n",
- depth * 2, "",
- width, (unsigned long long) r->start,
- width, (unsigned long long) r->end,
- r->name ? r->name : "<BAD>");
- return 0;
- }
- static const struct seq_operations resource_op = {
- .start = r_start,
- .next = r_next,
- .stop = r_stop,
- .show = r_show,
- };
- static int ioports_open(struct inode *inode, struct file *file)
- {
- int res = seq_open(file, &resource_op);
- if (!res) {
- struct seq_file *m = file->private_data;
- m->private = &ioport_resource;
- }
- return res;
- }
- static int iomem_open(struct inode *inode, struct file *file)
- {
- int res = seq_open(file, &resource_op);
- if (!res) {
- struct seq_file *m = file->private_data;
- m->private = &iomem_resource;
- }
- return res;
- }
- static const struct file_operations proc_ioports_operations = {
- .open = ioports_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = seq_release,
- };
- static const struct file_operations proc_iomem_operations = {
- .open = iomem_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = seq_release,
- };
- static int __init ioresources_init(void)
- {
- proc_create("ioports", 0, NULL, &proc_ioports_operations);
- proc_create("iomem", 0, NULL, &proc_iomem_operations);
- return 0;
- }
- __initcall(ioresources_init);
- #endif /* CONFIG_PROC_FS */
- /* Return the conflict entry if you can't request it */
- static struct resource * __request_resource(struct resource *root, struct resource *new)
- {
- resource_size_t start = new->start;
- resource_size_t end = new->end;
- struct resource *tmp, **p;
- if (end < start)
- return root;
- if (start < root->start)
- return root;
- if (end > root->end)
- return root;
- p = &root->child;
- for (;;) {
- tmp = *p;
- if (!tmp || tmp->start > end) {
- new->sibling = tmp;
- *p = new;
- new->parent = root;
- return NULL;
- }
- p = &tmp->sibling;
- if (tmp->end < start)
- continue;
- return tmp;
- }
- }
- static int __release_resource(struct resource *old)
- {
- struct resource *tmp, **p;
- p = &old->parent->child;
- for (;;) {
- tmp = *p;
- if (!tmp)
- break;
- if (tmp == old) {
- *p = tmp->sibling;
- old->parent = NULL;
- return 0;
- }
- p = &tmp->sibling;
- }
- return -EINVAL;
- }
- static void __release_child_resources(struct resource *r)
- {
- struct resource *tmp, *p;
- resource_size_t size;
- p = r->child;
- r->child = NULL;
- while (p) {
- tmp = p;
- p = p->sibling;
- tmp->parent = NULL;
- tmp->sibling = NULL;
- __release_child_resources(tmp);
- printk(KERN_DEBUG "release child resource %pR\n", tmp);
- /* need to restore size, and keep flags */
- size = resource_size(tmp);
- tmp->start = 0;
- tmp->end = size - 1;
- }
- }
- void release_child_resources(struct resource *r)
- {
- write_lock(&resource_lock);
- __release_child_resources(r);
- write_unlock(&resource_lock);
- }
- /**
- * request_resource_conflict - request and reserve an I/O or memory resource
- * @root: root resource descriptor
- * @new: resource descriptor desired by caller
- *
- * Returns 0 for success, conflict resource on error.
- */
- struct resource *request_resource_conflict(struct resource *root, struct resource *new)
- {
- struct resource *conflict;
- write_lock(&resource_lock);
- conflict = __request_resource(root, new);
- write_unlock(&resource_lock);
- return conflict;
- }
- /**
- * request_resource - request and reserve an I/O or memory resource
- * @root: root resource descriptor
- * @new: resource descriptor desired by caller
- *
- * Returns 0 for success, negative error code on error.
- */
- int request_resource(struct resource *root, struct resource *new)
- {
- struct resource *conflict;
- conflict = request_resource_conflict(root, new);
- return conflict ? -EBUSY : 0;
- }
- EXPORT_SYMBOL(request_resource);
- /**
- * release_resource - release a previously reserved resource
- * @old: resource pointer
- */
- int release_resource(struct resource *old)
- {
- int retval;
- write_lock(&resource_lock);
- retval = __release_resource(old);
- write_unlock(&resource_lock);
- return retval;
- }
- EXPORT_SYMBOL(release_resource);
- #if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
- /*
- * Finds the lowest memory reosurce exists within [res->start.res->end)
- * the caller must specify res->start, res->end, res->flags and "name".
- * If found, returns 0, res is overwritten, if not found, returns -1.
- */
- static int find_next_system_ram(struct resource *res, char *name)
- {
- resource_size_t start, end;
- struct resource *p;
- BUG_ON(!res);
- start = res->start;
- end = res->end;
- BUG_ON(start >= end);
- read_lock(&resource_lock);
- for (p = iomem_resource.child; p ; p = p->sibling) {
- /* system ram is just marked as IORESOURCE_MEM */
- if (p->flags != res->flags)
- continue;
- if (name && strcmp(p->name, name))
- continue;
- if (p->start > end) {
- p = NULL;
- break;
- }
- if ((p->end >= start) && (p->start < end))
- break;
- }
- read_unlock(&resource_lock);
- if (!p)
- return -1;
- /* copy data */
- if (res->start < p->start)
- res->start = p->start;
- if (res->end > p->end)
- res->end = p->end;
- return 0;
- }
- /*
- * This function calls callback against all memory range of "System RAM"
- * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
- * Now, this function is only for "System RAM".
- */
- int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
- void *arg, int (*func)(unsigned long, unsigned long, void *))
- {
- struct resource res;
- unsigned long pfn, end_pfn;
- u64 orig_end;
- int ret = -1;
- res.start = (u64) start_pfn << PAGE_SHIFT;
- res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
- res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
- orig_end = res.end;
- while ((res.start < res.end) &&
- (find_next_system_ram(&res, "System RAM") >= 0)) {
- pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT;
- end_pfn = (res.end + 1) >> PAGE_SHIFT;
- if (end_pfn > pfn)
- ret = (*func)(pfn, end_pfn - pfn, arg);
- if (ret)
- break;
- res.start = res.end + 1;
- res.end = orig_end;
- }
- return ret;
- }
- #endif
- static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg)
- {
- return 1;
- }
- /*
- * This generic page_is_ram() returns true if specified address is
- * registered as "System RAM" in iomem_resource list.
- */
- int __weak page_is_ram(unsigned long pfn)
- {
- return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
- }
- void __weak arch_remove_reservations(struct resource *avail)
- {
- }
- static resource_size_t simple_align_resource(void *data,
- const struct resource *avail,
- resource_size_t size,
- resource_size_t align)
- {
- return avail->start;
- }
- static void resource_clip(struct resource *res, resource_size_t min,
- resource_size_t max)
- {
- if (res->start < min)
- res->start = min;
- if (res->end > max)
- res->end = max;
- }
- static bool resource_contains(struct resource *res1, struct resource *res2)
- {
- return res1->start <= res2->start && res1->end >= res2->end;
- }
- /*
- * Find empty slot in the resource tree with the given range and
- * alignment constraints
- */
- static int __find_resource(struct resource *root, struct resource *old,
- struct resource *new,
- resource_size_t size,
- struct resource_constraint *constraint)
- {
- struct resource *this = root->child;
- struct resource tmp = *new, avail, alloc;
- tmp.flags = new->flags;
- tmp.start = root->start;
- /*
- * Skip past an allocated resource that starts at 0, since the assignment
- * of this->start - 1 to tmp->end below would cause an underflow.
- */
- if (this && this->start == root->start) {
- tmp.start = (this == old) ? old->start : this->end + 1;
- this = this->sibling;
- }
- for(;;) {
- if (this)
- tmp.end = (this == old) ? this->end : this->start - 1;
- else
- tmp.end = root->end;
- resource_clip(&tmp, constraint->min, constraint->max);
- arch_remove_reservations(&tmp);
- /* Check for overflow after ALIGN() */
- avail = *new;
- avail.start = ALIGN(tmp.start, constraint->align);
- avail.end = tmp.end;
- if (avail.start >= tmp.start) {
- alloc.start = constraint->alignf(constraint->alignf_data, &avail,
- size, constraint->align);
- alloc.end = alloc.start + size - 1;
- if (resource_contains(&avail, &alloc)) {
- new->start = alloc.start;
- new->end = alloc.end;
- return 0;
- }
- }
- if (!this)
- break;
- if (this != old)
- tmp.start = this->end + 1;
- this = this->sibling;
- }
- return -EBUSY;
- }
- /*
- * Find empty slot in the resource tree given range and alignment.
- */
- static int find_resource(struct resource *root, struct resource *new,
- resource_size_t size,
- struct resource_constraint *constraint)
- {
- return __find_resource(root, NULL, new, size, constraint);
- }
- /**
- * reallocate_resource - allocate a slot in the resource tree given range & alignment.
- * The resource will be relocated if the new size cannot be reallocated in the
- * current location.
- *
- * @root: root resource descriptor
- * @old: resource descriptor desired by caller
- * @newsize: new size of the resource descriptor
- * @constraint: the size and alignment constraints to be met.
- */
- int reallocate_resource(struct resource *root, struct resource *old,
- resource_size_t newsize,
- struct resource_constraint *constraint)
- {
- int err=0;
- struct resource new = *old;
- struct resource *conflict;
- write_lock(&resource_lock);
- if ((err = __find_resource(root, old, &new, newsize, constraint)))
- goto out;
- if (resource_contains(&new, old)) {
- old->start = new.start;
- old->end = new.end;
- goto out;
- }
- if (old->child) {
- err = -EBUSY;
- goto out;
- }
- if (resource_contains(old, &new)) {
- old->start = new.start;
- old->end = new.end;
- } else {
- __release_resource(old);
- *old = new;
- conflict = __request_resource(root, old);
- BUG_ON(conflict);
- }
- out:
- write_unlock(&resource_lock);
- return err;
- }
- /**
- * allocate_resource - allocate empty slot in the resource tree given range & alignment.
- * The resource will be reallocated with a new size if it was already allocated
- * @root: root resource descriptor
- * @new: resource descriptor desired by caller
- * @size: requested resource region size
- * @min: minimum size to allocate
- * @max: maximum size to allocate
- * @align: alignment requested, in bytes
- * @alignf: alignment function, optional, called if not NULL
- * @alignf_data: arbitrary data to pass to the @alignf function
- */
- int allocate_resource(struct resource *root, struct resource *new,
- resource_size_t size, resource_size_t min,
- resource_size_t max, resource_size_t align,
- resource_size_t (*alignf)(void *,
- const struct resource *,
- resource_size_t,
- resource_size_t),
- void *alignf_data)
- {
- int err;
- struct resource_constraint constraint;
- if (!alignf)
- alignf = simple_align_resource;
- constraint.min = min;
- constraint.max = max;
- constraint.align = align;
- constraint.alignf = alignf;
- constraint.alignf_data = alignf_data;
- if ( new->parent ) {
- /* resource is already allocated, try reallocating with
- the new constraints */
- return reallocate_resource(root, new, size, &constraint);
- }
- write_lock(&resource_lock);
- err = find_resource(root, new, size, &constraint);
- if (err >= 0 && __request_resource(root, new))
- err = -EBUSY;
- write_unlock(&resource_lock);
- return err;
- }
- EXPORT_SYMBOL(allocate_resource);
- /*
- * Insert a resource into the resource tree. If successful, return NULL,
- * otherwise return the conflicting resource (compare to __request_resource())
- */
- static struct resource * __insert_resource(struct resource *parent, struct resource *new)
- {
- struct resource *first, *next;
- for (;; parent = first) {
- first = __request_resource(parent, new);
- if (!first)
- return first;
- if (first == parent)
- return first;
- if (WARN_ON(first == new)) /* duplicated insertion */
- return first;
- if ((first->start > new->start) || (first->end < new->end))
- break;
- if ((first->start == new->start) && (first->end == new->end))
- break;
- }
- for (next = first; ; next = next->sibling) {
- /* Partial overlap? Bad, and unfixable */
- if (next->start < new->start || next->end > new->end)
- return next;
- if (!next->sibling)
- break;
- if (next->sibling->start > new->end)
- break;
- }
- new->parent = parent;
- new->sibling = next->sibling;
- new->child = first;
- next->sibling = NULL;
- for (next = first; next; next = next->sibling)
- next->parent = new;
- if (parent->child == first) {
- parent->child = new;
- } else {
- next = parent->child;
- while (next->sibling != first)
- next = next->sibling;
- next->sibling = new;
- }
- return NULL;
- }
- /**
- * insert_resource_conflict - Inserts resource in the resource tree
- * @parent: parent of the new resource
- * @new: new resource to insert
- *
- * Returns 0 on success, conflict resource if the resource can't be inserted.
- *
- * This function is equivalent to request_resource_conflict when no conflict
- * happens. If a conflict happens, and the conflicting resources
- * entirely fit within the range of the new resource, then the new
- * resource is inserted and the conflicting resources become children of
- * the new resource.
- */
- struct resource *insert_resource_conflict(struct resource *parent, struct resource *new)
- {
- struct resource *conflict;
- write_lock(&resource_lock);
- conflict = __insert_resource(parent, new);
- write_unlock(&resource_lock);
- return conflict;
- }
- /**
- * insert_resource - Inserts a resource in the resource tree
- * @parent: parent of the new resource
- * @new: new resource to insert
- *
- * Returns 0 on success, -EBUSY if the resource can't be inserted.
- */
- int insert_resource(struct resource *parent, struct resource *new)
- {
- struct resource *conflict;
- conflict = insert_resource_conflict(parent, new);
- return conflict ? -EBUSY : 0;
- }
- /**
- * insert_resource_expand_to_fit - Insert a resource into the resource tree
- * @root: root resource descriptor
- * @new: new resource to insert
- *
- * Insert a resource into the resource tree, possibly expanding it in order
- * to make it encompass any conflicting resources.
- */
- void insert_resource_expand_to_fit(struct resource *root, struct resource *new)
- {
- if (new->parent)
- return;
- write_lock(&resource_lock);
- for (;;) {
- struct resource *conflict;
- conflict = __insert_resource(root, new);
- if (!conflict)
- break;
- if (conflict == root)
- break;
- /* Ok, expand resource to cover the conflict, then try again .. */
- if (conflict->start < new->start)
- new->start = conflict->start;
- if (conflict->end > new->end)
- new->end = conflict->end;
- printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name);
- }
- write_unlock(&resource_lock);
- }
- /**
- * adjust_resource - modify a resource's start and size
- * @res: resource to modify
- * @start: new start value
- * @size: new size
- *
- * Given an existing resource, change its start and size to match the
- * arguments. Returns 0 on success, -EBUSY if it can't fit.
- * Existing children of the resource are assumed to be immutable.
- */
- int adjust_resource(struct resource *res, resource_size_t start, resource_size_t size)
- {
- struct resource *tmp, *parent = res->parent;
- resource_size_t end = start + size - 1;
- int result = -EBUSY;
- write_lock(&resource_lock);
- if ((start < parent->start) || (end > parent->end))
- goto out;
- for (tmp = res->child; tmp; tmp = tmp->sibling) {
- if ((tmp->start < start) || (tmp->end > end))
- goto out;
- }
- if (res->sibling && (res->sibling->start <= end))
- goto out;
- tmp = parent->child;
- if (tmp != res) {
- while (tmp->sibling != res)
- tmp = tmp->sibling;
- if (start <= tmp->end)
- goto out;
- }
- res->start = start;
- res->end = end;
- result = 0;
- out:
- write_unlock(&resource_lock);
- return result;
- }
- static void __init __reserve_region_with_split(struct resource *root,
- resource_size_t start, resource_size_t end,
- const char *name)
- {
- struct resource *parent = root;
- struct resource *conflict;
- struct resource *res = kzalloc(sizeof(*res), GFP_ATOMIC);
- if (!res)
- return;
- res->name = name;
- res->start = start;
- res->end = end;
- res->flags = IORESOURCE_BUSY;
- conflict = __request_resource(parent, res);
- if (!conflict)
- return;
- /* failed, split and try again */
- kfree(res);
- /* conflict covered whole area */
- if (conflict->start <= start && conflict->end >= end)
- return;
- if (conflict->start > start)
- __reserve_region_with_split(root, start, conflict->start-1, name);
- if (conflict->end < end)
- __reserve_region_with_split(root, conflict->end+1, end, name);
- }
- void __init reserve_region_with_split(struct resource *root,
- resource_size_t start, resource_size_t end,
- const char *name)
- {
- write_lock(&resource_lock);
- __reserve_region_with_split(root, start, end, name);
- write_unlock(&resource_lock);
- }
- EXPORT_SYMBOL(adjust_resource);
- /**
- * resource_alignment - calculate resource's alignment
- * @res: resource pointer
- *
- * Returns alignment on success, 0 (invalid alignment) on failure.
- */
- resource_size_t resource_alignment(struct resource *res)
- {
- switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) {
- case IORESOURCE_SIZEALIGN:
- return resource_size(res);
- case IORESOURCE_STARTALIGN:
- return res->start;
- default:
- return 0;
- }
- }
- /*
- * This is compatibility stuff for IO resources.
- *
- * Note how this, unlike the above, knows about
- * the IO flag meanings (busy etc).
- *
- * request_region creates a new busy region.
- *
- * check_region returns non-zero if the area is already busy.
- *
- * release_region releases a matching busy region.
- */
- static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait);
- /**
- * __request_region - create a new busy resource region
- * @parent: parent resource descriptor
- * @start: resource start address
- * @n: resource region size
- * @name: reserving caller's ID string
- * @flags: IO resource flags
- */
- struct resource * __request_region(struct resource *parent,
- resource_size_t start, resource_size_t n,
- const char *name, int flags)
- {
- DECLARE_WAITQUEUE(wait, current);
- struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL);
- if (!res)
- return NULL;
- res->name = name;
- res->start = start;
- res->end = start + n - 1;
- res->flags = IORESOURCE_BUSY;
- res->flags |= flags;
- write_lock(&resource_lock);
- for (;;) {
- struct resource *conflict;
- conflict = __request_resource(parent, res);
- if (!conflict)
- break;
- if (conflict != parent) {
- parent = conflict;
- if (!(conflict->flags & IORESOURCE_BUSY))
- continue;
- }
- if (conflict->flags & flags & IORESOURCE_MUXED) {
- add_wait_queue(&muxed_resource_wait, &wait);
- write_unlock(&resource_lock);
- set_current_state(TASK_UNINTERRUPTIBLE);
- schedule();
- remove_wait_queue(&muxed_resource_wait, &wait);
- write_lock(&resource_lock);
- continue;
- }
- /* Uhhuh, that didn't work out.. */
- kfree(res);
- res = NULL;
- break;
- }
- write_unlock(&resource_lock);
- return res;
- }
- EXPORT_SYMBOL(__request_region);
- /**
- * __check_region - check if a resource region is busy or free
- * @parent: parent resource descriptor
- * @start: resource start address
- * @n: resource region size
- *
- * Returns 0 if the region is free at the moment it is checked,
- * returns %-EBUSY if the region is busy.
- *
- * NOTE:
- * This function is deprecated because its use is racy.
- * Even if it returns 0, a subsequent call to request_region()
- * may fail because another driver etc. just allocated the region.
- * Do NOT use it. It will be removed from the kernel.
- */
- int __check_region(struct resource *parent, resource_size_t start,
- resource_size_t n)
- {
- struct resource * res;
- res = __request_region(parent, start, n, "check-region", 0);
- if (!res)
- return -EBUSY;
- release_resource(res);
- kfree(res);
- return 0;
- }
- EXPORT_SYMBOL(__check_region);
- /**
- * __release_region - release a previously reserved resource region
- * @parent: parent resource descriptor
- * @start: resource start address
- * @n: resource region size
- *
- * The described resource region must match a currently busy region.
- */
- void __release_region(struct resource *parent, resource_size_t start,
- resource_size_t n)
- {
- struct resource **p;
- resource_size_t end;
- p = &parent->child;
- end = start + n - 1;
- write_lock(&resource_lock);
- for (;;) {
- struct resource *res = *p;
- if (!res)
- break;
- if (res->start <= start && res->end >= end) {
- if (!(res->flags & IORESOURCE_BUSY)) {
- p = &res->child;
- continue;
- }
- if (res->start != start || res->end != end)
- break;
- *p = res->sibling;
- write_unlock(&resource_lock);
- if (res->flags & IORESOURCE_MUXED)
- wake_up(&muxed_resource_wait);
- kfree(res);
- return;
- }
- p = &res->sibling;
- }
- write_unlock(&resource_lock);
- printk(KERN_WARNING "Trying to free nonexistent resource "
- "<%016llx-%016llx>\n", (unsigned long long)start,
- (unsigned long long)end);
- }
- EXPORT_SYMBOL(__release_region);
- /*
- * Managed region resource
- */
- struct region_devres {
- struct resource *parent;
- resource_size_t start;
- resource_size_t n;
- };
- static void devm_region_release(struct device *dev, void *res)
- {
- struct region_devres *this = res;
- __release_region(this->parent, this->start, this->n);
- }
- static int devm_region_match(struct device *dev, void *res, void *match_data)
- {
- struct region_devres *this = res, *match = match_data;
- return this->parent == match->parent &&
- this->start == match->start && this->n == match->n;
- }
- struct resource * __devm_request_region(struct device *dev,
- struct resource *parent, resource_size_t start,
- resource_size_t n, const char *name)
- {
- struct region_devres *dr = NULL;
- struct resource *res;
- dr = devres_alloc(devm_region_release, sizeof(struct region_devres),
- GFP_KERNEL);
- if (!dr)
- return NULL;
- dr->parent = parent;
- dr->start = start;
- dr->n = n;
- res = __request_region(parent, start, n, name, 0);
- if (res)
- devres_add(dev, dr);
- else
- devres_free(dr);
- return res;
- }
- EXPORT_SYMBOL(__devm_request_region);
- void __devm_release_region(struct device *dev, struct resource *parent,
- resource_size_t start, resource_size_t n)
- {
- struct region_devres match_data = { parent, start, n };
- __release_region(parent, start, n);
- WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match,
- &match_data));
- }
- EXPORT_SYMBOL(__devm_release_region);
- /*
- * Called from init/main.c to reserve IO ports.
- */
- #define MAXRESERVE 4
- static int __init reserve_setup(char *str)
- {
- static int reserved;
- static struct resource reserve[MAXRESERVE];
- for (;;) {
- unsigned int io_start, io_num;
- int x = reserved;
- if (get_option (&str, &io_start) != 2)
- break;
- if (get_option (&str, &io_num) == 0)
- break;
- if (x < MAXRESERVE) {
- struct resource *res = reserve + x;
- res->name = "reserved";
- res->start = io_start;
- res->end = io_start + io_num - 1;
- res->flags = IORESOURCE_BUSY;
- res->child = NULL;
- if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0)
- reserved = x+1;
- }
- }
- return 1;
- }
- __setup("reserve=", reserve_setup);
- /*
- * Check if the requested addr and size spans more than any slot in the
- * iomem resource tree.
- */
- int iomem_map_sanity_check(resource_size_t addr, unsigned long size)
- {
- struct resource *p = &iomem_resource;
- int err = 0;
- loff_t l;
- read_lock(&resource_lock);
- for (p = p->child; p ; p = r_next(NULL, p, &l)) {
- /*
- * We can probably skip the resources without
- * IORESOURCE_IO attribute?
- */
- if (p->start >= addr + size)
- continue;
- if (p->end < addr)
- continue;
- if (PFN_DOWN(p->start) <= PFN_DOWN(addr) &&
- PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1))
- continue;
- /*
- * if a resource is "BUSY", it's not a hardware resource
- * but a driver mapping of such a resource; we don't want
- * to warn for those; some drivers legitimately map only
- * partial hardware resources. (example: vesafb)
- */
- if (p->flags & IORESOURCE_BUSY)
- continue;
- printk(KERN_WARNING "resource map sanity check conflict: "
- "0x%llx 0x%llx 0x%llx 0x%llx %s\n",
- (unsigned long long)addr,
- (unsigned long long)(addr + size - 1),
- (unsigned long long)p->start,
- (unsigned long long)p->end,
- p->name);
- err = -1;
- break;
- }
- read_unlock(&resource_lock);
- return err;
- }
- #ifdef CONFIG_STRICT_DEVMEM
- static int strict_iomem_checks = 1;
- #else
- static int strict_iomem_checks;
- #endif
- /*
- * check if an address is reserved in the iomem resource tree
- * returns 1 if reserved, 0 if not reserved.
- */
- int iomem_is_exclusive(u64 addr)
- {
- struct resource *p = &iomem_resource;
- int err = 0;
- loff_t l;
- int size = PAGE_SIZE;
- if (!strict_iomem_checks)
- return 0;
- addr = addr & PAGE_MASK;
- read_lock(&resource_lock);
- for (p = p->child; p ; p = r_next(NULL, p, &l)) {
- /*
- * We can probably skip the resources without
- * IORESOURCE_IO attribute?
- */
- if (p->start >= addr + size)
- break;
- if (p->end < addr)
- continue;
- if (p->flags & IORESOURCE_BUSY &&
- p->flags & IORESOURCE_EXCLUSIVE) {
- err = 1;
- break;
- }
- }
- read_unlock(&resource_lock);
- return err;
- }
- static int __init strict_iomem(char *str)
- {
- if (strstr(str, "relaxed"))
- strict_iomem_checks = 0;
- if (strstr(str, "strict"))
- strict_iomem_checks = 1;
- return 1;
- }
- __setup("iomem=", strict_iomem);
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