mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 19:00:25 +00:00
![Denis V. Lunev](/assets/img/avatar_default.png)
Use proc_create()/proc_create_data() to make sure that ->proc_fops and ->data be setup before gluing PDE to main tree. Signed-off-by: Denis V. Lunev <den@openvz.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
727 lines
16 KiB
C
727 lines
16 KiB
C
/*
|
|
* 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/seq_file.h>
|
|
#include <linux/device.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);
|
|
|
|
static DEFINE_RWLOCK(resource_lock);
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
|
|
enum { MAX_IORES_LEVEL = 5 };
|
|
|
|
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;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
/**
|
|
* 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;
|
|
|
|
write_lock(&resource_lock);
|
|
conflict = __request_resource(root, new);
|
|
write_unlock(&resource_lock);
|
|
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_MEMORY_HOTPLUG) && !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.
|
|
* If found, returns 0, res is overwritten, if not found, returns -1.
|
|
*/
|
|
static int find_next_system_ram(struct resource *res)
|
|
{
|
|
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 (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;
|
|
}
|
|
int
|
|
walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg,
|
|
int (*func)(unsigned long, unsigned long, void *))
|
|
{
|
|
struct resource res;
|
|
unsigned long pfn, len;
|
|
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) >= 0)) {
|
|
pfn = (unsigned long)(res.start >> PAGE_SHIFT);
|
|
len = (unsigned long)((res.end + 1 - res.start) >> PAGE_SHIFT);
|
|
ret = (*func)(pfn, len, arg);
|
|
if (ret)
|
|
break;
|
|
res.start = res.end + 1;
|
|
res.end = orig_end;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
#endif
|
|
|
|
/*
|
|
* 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, resource_size_t min,
|
|
resource_size_t max, resource_size_t align,
|
|
void (*alignf)(void *, struct resource *,
|
|
resource_size_t, resource_size_t),
|
|
void *alignf_data)
|
|
{
|
|
struct resource *this = root->child;
|
|
|
|
new->start = root->start;
|
|
/*
|
|
* Skip past an allocated resource that starts at 0, since the assignment
|
|
* of this->start - 1 to new->end below would cause an underflow.
|
|
*/
|
|
if (this && this->start == 0) {
|
|
new->start = this->end + 1;
|
|
this = this->sibling;
|
|
}
|
|
for(;;) {
|
|
if (this)
|
|
new->end = this->start - 1;
|
|
else
|
|
new->end = root->end;
|
|
if (new->start < min)
|
|
new->start = min;
|
|
if (new->end > max)
|
|
new->end = max;
|
|
new->start = ALIGN(new->start, align);
|
|
if (alignf)
|
|
alignf(alignf_data, new, size, align);
|
|
if (new->start < new->end && new->end - new->start >= size - 1) {
|
|
new->end = new->start + size - 1;
|
|
return 0;
|
|
}
|
|
if (!this)
|
|
break;
|
|
new->start = this->end + 1;
|
|
this = this->sibling;
|
|
}
|
|
return -EBUSY;
|
|
}
|
|
|
|
/**
|
|
* allocate_resource - allocate empty slot in the resource tree given range & alignment
|
|
* @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,
|
|
void (*alignf)(void *, struct resource *,
|
|
resource_size_t, resource_size_t),
|
|
void *alignf_data)
|
|
{
|
|
int err;
|
|
|
|
write_lock(&resource_lock);
|
|
err = find_resource(root, new, size, min, max, align, alignf, alignf_data);
|
|
if (err >= 0 && __request_resource(root, new))
|
|
err = -EBUSY;
|
|
write_unlock(&resource_lock);
|
|
return err;
|
|
}
|
|
|
|
EXPORT_SYMBOL(allocate_resource);
|
|
|
|
/**
|
|
* 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.
|
|
*
|
|
* This function is equivalent to request_resource 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.
|
|
*/
|
|
int insert_resource(struct resource *parent, struct resource *new)
|
|
{
|
|
int result;
|
|
struct resource *first, *next;
|
|
|
|
write_lock(&resource_lock);
|
|
|
|
for (;; parent = first) {
|
|
result = 0;
|
|
first = __request_resource(parent, new);
|
|
if (!first)
|
|
goto out;
|
|
|
|
result = -EBUSY;
|
|
if (first == parent)
|
|
goto out;
|
|
|
|
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)
|
|
goto out;
|
|
if (!next->sibling)
|
|
break;
|
|
if (next->sibling->start > new->end)
|
|
break;
|
|
}
|
|
|
|
result = 0;
|
|
|
|
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;
|
|
}
|
|
|
|
out:
|
|
write_unlock(&resource_lock);
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* 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;
|
|
}
|
|
|
|
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 res->end - res->start + 1;
|
|
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.
|
|
*/
|
|
|
|
/**
|
|
* __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
|
|
*/
|
|
struct resource * __request_region(struct resource *parent,
|
|
resource_size_t start, resource_size_t n,
|
|
const char *name)
|
|
{
|
|
struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL);
|
|
|
|
if (res) {
|
|
res->name = name;
|
|
res->start = start;
|
|
res->end = start + n - 1;
|
|
res->flags = IORESOURCE_BUSY;
|
|
|
|
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;
|
|
}
|
|
|
|
/* 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");
|
|
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);
|
|
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);
|
|
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 (;;) {
|
|
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);
|