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![Kevin Hao](/assets/img/avatar_default.png)
This line was introduced by fcb11918
("resources: add arch hook for
preventing allocation in reserved areas"). But the struct tmp was already
assigned to *new in the above line, so this seems superfluous. Just
remove it.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1362 lines
32 KiB
C
1362 lines
32 KiB
C
/*
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* linux/kernel/resource.c
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*
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* Copyright (C) 1999 Linus Torvalds
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* Copyright (C) 1999 Martin Mares <mj@ucw.cz>
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*
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* Arbitrary resource management.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/export.h>
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#include <linux/errno.h>
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#include <linux/ioport.h>
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#include <linux/init.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/fs.h>
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#include <linux/proc_fs.h>
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#include <linux/sched.h>
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#include <linux/seq_file.h>
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#include <linux/device.h>
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#include <linux/pfn.h>
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#include <linux/mm.h>
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#include <asm/io.h>
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struct resource ioport_resource = {
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.name = "PCI IO",
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.start = 0,
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.end = IO_SPACE_LIMIT,
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.flags = IORESOURCE_IO,
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};
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EXPORT_SYMBOL(ioport_resource);
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struct resource iomem_resource = {
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.name = "PCI mem",
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.start = 0,
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.end = -1,
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.flags = IORESOURCE_MEM,
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};
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EXPORT_SYMBOL(iomem_resource);
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/* constraints to be met while allocating resources */
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struct resource_constraint {
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resource_size_t min, max, align;
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resource_size_t (*alignf)(void *, const struct resource *,
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resource_size_t, resource_size_t);
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void *alignf_data;
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};
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static DEFINE_RWLOCK(resource_lock);
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/*
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* For memory hotplug, there is no way to free resource entries allocated
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* by boot mem after the system is up. So for reusing the resource entry
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* we need to remember the resource.
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*/
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static struct resource *bootmem_resource_free;
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static DEFINE_SPINLOCK(bootmem_resource_lock);
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static void *r_next(struct seq_file *m, void *v, loff_t *pos)
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{
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struct resource *p = v;
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(*pos)++;
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if (p->child)
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return p->child;
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while (!p->sibling && p->parent)
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p = p->parent;
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return p->sibling;
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}
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#ifdef CONFIG_PROC_FS
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enum { MAX_IORES_LEVEL = 5 };
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static void *r_start(struct seq_file *m, loff_t *pos)
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__acquires(resource_lock)
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{
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struct resource *p = m->private;
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loff_t l = 0;
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read_lock(&resource_lock);
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for (p = p->child; p && l < *pos; p = r_next(m, p, &l))
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;
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return p;
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}
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static void r_stop(struct seq_file *m, void *v)
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__releases(resource_lock)
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{
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read_unlock(&resource_lock);
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}
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static int r_show(struct seq_file *m, void *v)
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{
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struct resource *root = m->private;
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struct resource *r = v, *p;
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int width = root->end < 0x10000 ? 4 : 8;
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int depth;
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for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent)
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if (p->parent == root)
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break;
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seq_printf(m, "%*s%0*llx-%0*llx : %s\n",
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depth * 2, "",
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width, (unsigned long long) r->start,
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width, (unsigned long long) r->end,
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r->name ? r->name : "<BAD>");
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return 0;
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}
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static const struct seq_operations resource_op = {
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.start = r_start,
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.next = r_next,
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.stop = r_stop,
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.show = r_show,
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};
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static int ioports_open(struct inode *inode, struct file *file)
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{
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int res = seq_open(file, &resource_op);
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if (!res) {
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struct seq_file *m = file->private_data;
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m->private = &ioport_resource;
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}
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return res;
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}
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static int iomem_open(struct inode *inode, struct file *file)
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{
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int res = seq_open(file, &resource_op);
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if (!res) {
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struct seq_file *m = file->private_data;
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m->private = &iomem_resource;
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}
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return res;
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}
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static const struct file_operations proc_ioports_operations = {
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.open = ioports_open,
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.read = seq_read,
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.llseek = seq_lseek,
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.release = seq_release,
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};
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static const struct file_operations proc_iomem_operations = {
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.open = iomem_open,
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.read = seq_read,
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.llseek = seq_lseek,
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.release = seq_release,
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};
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static int __init ioresources_init(void)
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{
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proc_create("ioports", 0, NULL, &proc_ioports_operations);
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proc_create("iomem", 0, NULL, &proc_iomem_operations);
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return 0;
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}
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__initcall(ioresources_init);
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#endif /* CONFIG_PROC_FS */
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static void free_resource(struct resource *res)
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{
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if (!res)
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return;
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if (!PageSlab(virt_to_head_page(res))) {
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spin_lock(&bootmem_resource_lock);
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res->sibling = bootmem_resource_free;
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bootmem_resource_free = res;
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spin_unlock(&bootmem_resource_lock);
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} else {
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kfree(res);
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}
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}
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static struct resource *alloc_resource(gfp_t flags)
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{
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struct resource *res = NULL;
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spin_lock(&bootmem_resource_lock);
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if (bootmem_resource_free) {
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res = bootmem_resource_free;
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bootmem_resource_free = res->sibling;
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}
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spin_unlock(&bootmem_resource_lock);
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if (res)
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memset(res, 0, sizeof(struct resource));
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else
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res = kzalloc(sizeof(struct resource), flags);
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return res;
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}
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/* Return the conflict entry if you can't request it */
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static struct resource * __request_resource(struct resource *root, struct resource *new)
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{
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resource_size_t start = new->start;
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resource_size_t end = new->end;
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struct resource *tmp, **p;
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if (end < start)
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return root;
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if (start < root->start)
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return root;
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if (end > root->end)
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return root;
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p = &root->child;
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for (;;) {
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tmp = *p;
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if (!tmp || tmp->start > end) {
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new->sibling = tmp;
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*p = new;
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new->parent = root;
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return NULL;
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}
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p = &tmp->sibling;
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if (tmp->end < start)
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continue;
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return tmp;
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}
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}
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static int __release_resource(struct resource *old)
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{
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struct resource *tmp, **p;
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p = &old->parent->child;
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for (;;) {
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tmp = *p;
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if (!tmp)
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break;
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if (tmp == old) {
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*p = tmp->sibling;
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old->parent = NULL;
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return 0;
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}
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p = &tmp->sibling;
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}
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return -EINVAL;
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}
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static void __release_child_resources(struct resource *r)
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{
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struct resource *tmp, *p;
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resource_size_t size;
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p = r->child;
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r->child = NULL;
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while (p) {
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tmp = p;
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p = p->sibling;
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tmp->parent = NULL;
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tmp->sibling = NULL;
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__release_child_resources(tmp);
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printk(KERN_DEBUG "release child resource %pR\n", tmp);
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/* need to restore size, and keep flags */
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size = resource_size(tmp);
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tmp->start = 0;
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tmp->end = size - 1;
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}
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}
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void release_child_resources(struct resource *r)
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{
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write_lock(&resource_lock);
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__release_child_resources(r);
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write_unlock(&resource_lock);
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}
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/**
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* request_resource_conflict - request and reserve an I/O or memory resource
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* @root: root resource descriptor
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* @new: resource descriptor desired by caller
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*
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* Returns 0 for success, conflict resource on error.
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*/
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struct resource *request_resource_conflict(struct resource *root, struct resource *new)
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{
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struct resource *conflict;
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write_lock(&resource_lock);
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conflict = __request_resource(root, new);
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write_unlock(&resource_lock);
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return conflict;
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}
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/**
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* request_resource - request and reserve an I/O or memory resource
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* @root: root resource descriptor
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* @new: resource descriptor desired by caller
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*
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* Returns 0 for success, negative error code on error.
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*/
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int request_resource(struct resource *root, struct resource *new)
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{
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struct resource *conflict;
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conflict = request_resource_conflict(root, new);
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return conflict ? -EBUSY : 0;
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}
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EXPORT_SYMBOL(request_resource);
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/**
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* release_resource - release a previously reserved resource
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* @old: resource pointer
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*/
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int release_resource(struct resource *old)
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{
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int retval;
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write_lock(&resource_lock);
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retval = __release_resource(old);
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write_unlock(&resource_lock);
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return retval;
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}
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EXPORT_SYMBOL(release_resource);
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#if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
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/*
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* Finds the lowest memory reosurce exists within [res->start.res->end)
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* the caller must specify res->start, res->end, res->flags and "name".
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* If found, returns 0, res is overwritten, if not found, returns -1.
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*/
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static int find_next_system_ram(struct resource *res, char *name)
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{
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resource_size_t start, end;
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struct resource *p;
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BUG_ON(!res);
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start = res->start;
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end = res->end;
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BUG_ON(start >= end);
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read_lock(&resource_lock);
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for (p = iomem_resource.child; p ; p = p->sibling) {
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/* system ram is just marked as IORESOURCE_MEM */
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if (p->flags != res->flags)
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continue;
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if (name && strcmp(p->name, name))
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continue;
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if (p->start > end) {
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p = NULL;
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break;
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}
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if ((p->end >= start) && (p->start < end))
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break;
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}
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read_unlock(&resource_lock);
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if (!p)
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return -1;
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/* copy data */
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if (res->start < p->start)
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res->start = p->start;
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if (res->end > p->end)
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res->end = p->end;
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return 0;
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}
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/*
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* This function calls callback against all memory range of "System RAM"
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* which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
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* Now, this function is only for "System RAM".
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*/
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int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
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void *arg, int (*func)(unsigned long, unsigned long, void *))
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{
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struct resource res;
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unsigned long pfn, end_pfn;
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u64 orig_end;
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int ret = -1;
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res.start = (u64) start_pfn << PAGE_SHIFT;
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res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
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res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
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orig_end = res.end;
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while ((res.start < res.end) &&
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(find_next_system_ram(&res, "System RAM") >= 0)) {
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pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT;
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end_pfn = (res.end + 1) >> PAGE_SHIFT;
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if (end_pfn > pfn)
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ret = (*func)(pfn, end_pfn - pfn, arg);
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if (ret)
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break;
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res.start = res.end + 1;
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res.end = orig_end;
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}
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return ret;
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}
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#endif
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static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg)
|
|
{
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return 1;
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}
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/*
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* This generic page_is_ram() returns true if specified address is
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* registered as "System RAM" in iomem_resource list.
|
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*/
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int __weak page_is_ram(unsigned long pfn)
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{
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return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
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}
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EXPORT_SYMBOL_GPL(page_is_ram);
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|
|
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void __weak arch_remove_reservations(struct resource *avail)
|
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{
|
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}
|
|
|
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static resource_size_t simple_align_resource(void *data,
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const struct resource *avail,
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resource_size_t size,
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resource_size_t align)
|
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{
|
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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)
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|
res->end = max;
|
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}
|
|
|
|
static bool resource_contains(struct resource *res1, struct resource *res2)
|
|
{
|
|
return res1->start <= res2->start && res1->end >= res2->end;
|
|
}
|
|
|
|
/*
|
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* Find empty slot in the resource tree with the given range and
|
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* alignment constraints
|
|
*/
|
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static int __find_resource(struct resource *root, struct resource *old,
|
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struct resource *new,
|
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resource_size_t size,
|
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struct resource_constraint *constraint)
|
|
{
|
|
struct resource *this = root->child;
|
|
struct resource tmp = *new, avail, alloc;
|
|
|
|
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;
|
|
|
|
if (tmp.end < tmp.start)
|
|
goto next;
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
next: if (!this || this->end == root->end)
|
|
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 boundary to allocate
|
|
* @max: maximum boundary 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);
|
|
|
|
/**
|
|
* lookup_resource - find an existing resource by a resource start address
|
|
* @root: root resource descriptor
|
|
* @start: resource start address
|
|
*
|
|
* Returns a pointer to the resource if found, NULL otherwise
|
|
*/
|
|
struct resource *lookup_resource(struct resource *root, resource_size_t start)
|
|
{
|
|
struct resource *res;
|
|
|
|
read_lock(&resource_lock);
|
|
for (res = root->child; res; res = res->sibling) {
|
|
if (res->start == start)
|
|
break;
|
|
}
|
|
read_unlock(&resource_lock);
|
|
|
|
return res;
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
}
|
|
|
|
static 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;
|
|
|
|
if (!parent)
|
|
goto skip;
|
|
|
|
if ((start < parent->start) || (end > parent->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;
|
|
}
|
|
|
|
skip:
|
|
for (tmp = res->child; tmp; tmp = tmp->sibling)
|
|
if ((tmp->start < start) || (tmp->end > end))
|
|
goto out;
|
|
|
|
res->start = start;
|
|
res->end = end;
|
|
result = 0;
|
|
|
|
out:
|
|
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)
|
|
{
|
|
int result;
|
|
|
|
write_lock(&resource_lock);
|
|
result = __adjust_resource(res, start, size);
|
|
write_unlock(&resource_lock);
|
|
return result;
|
|
}
|
|
EXPORT_SYMBOL(adjust_resource);
|
|
|
|
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 = alloc_resource(GFP_ATOMIC);
|
|
struct resource *next_res = NULL;
|
|
|
|
if (!res)
|
|
return;
|
|
|
|
res->name = name;
|
|
res->start = start;
|
|
res->end = end;
|
|
res->flags = IORESOURCE_BUSY;
|
|
|
|
while (1) {
|
|
|
|
conflict = __request_resource(parent, res);
|
|
if (!conflict) {
|
|
if (!next_res)
|
|
break;
|
|
res = next_res;
|
|
next_res = NULL;
|
|
continue;
|
|
}
|
|
|
|
/* conflict covered whole area */
|
|
if (conflict->start <= res->start &&
|
|
conflict->end >= res->end) {
|
|
free_resource(res);
|
|
WARN_ON(next_res);
|
|
break;
|
|
}
|
|
|
|
/* failed, split and try again */
|
|
if (conflict->start > res->start) {
|
|
end = res->end;
|
|
res->end = conflict->start - 1;
|
|
if (conflict->end < end) {
|
|
next_res = alloc_resource(GFP_ATOMIC);
|
|
if (!next_res) {
|
|
free_resource(res);
|
|
break;
|
|
}
|
|
next_res->name = name;
|
|
next_res->start = conflict->end + 1;
|
|
next_res->end = end;
|
|
next_res->flags = IORESOURCE_BUSY;
|
|
}
|
|
} else {
|
|
res->start = conflict->end + 1;
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
void __init reserve_region_with_split(struct resource *root,
|
|
resource_size_t start, resource_size_t end,
|
|
const char *name)
|
|
{
|
|
int abort = 0;
|
|
|
|
write_lock(&resource_lock);
|
|
if (root->start > start || root->end < end) {
|
|
pr_err("requested range [0x%llx-0x%llx] not in root %pr\n",
|
|
(unsigned long long)start, (unsigned long long)end,
|
|
root);
|
|
if (start > root->end || end < root->start)
|
|
abort = 1;
|
|
else {
|
|
if (end > root->end)
|
|
end = root->end;
|
|
if (start < root->start)
|
|
start = root->start;
|
|
pr_err("fixing request to [0x%llx-0x%llx]\n",
|
|
(unsigned long long)start,
|
|
(unsigned long long)end);
|
|
}
|
|
dump_stack();
|
|
}
|
|
if (!abort)
|
|
__reserve_region_with_split(root, start, end, name);
|
|
write_unlock(&resource_lock);
|
|
}
|
|
|
|
/**
|
|
* 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 = alloc_resource(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.. */
|
|
free_resource(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);
|
|
free_resource(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);
|
|
free_resource(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);
|
|
|
|
#ifdef CONFIG_MEMORY_HOTREMOVE
|
|
/**
|
|
* release_mem_region_adjustable - release a previously reserved memory region
|
|
* @parent: parent resource descriptor
|
|
* @start: resource start address
|
|
* @size: resource region size
|
|
*
|
|
* This interface is intended for memory hot-delete. The requested region
|
|
* is released from a currently busy memory resource. The requested region
|
|
* must either match exactly or fit into a single busy resource entry. In
|
|
* the latter case, the remaining resource is adjusted accordingly.
|
|
* Existing children of the busy memory resource must be immutable in the
|
|
* request.
|
|
*
|
|
* Note:
|
|
* - Additional release conditions, such as overlapping region, can be
|
|
* supported after they are confirmed as valid cases.
|
|
* - When a busy memory resource gets split into two entries, the code
|
|
* assumes that all children remain in the lower address entry for
|
|
* simplicity. Enhance this logic when necessary.
|
|
*/
|
|
int release_mem_region_adjustable(struct resource *parent,
|
|
resource_size_t start, resource_size_t size)
|
|
{
|
|
struct resource **p;
|
|
struct resource *res;
|
|
struct resource *new_res;
|
|
resource_size_t end;
|
|
int ret = -EINVAL;
|
|
|
|
end = start + size - 1;
|
|
if ((start < parent->start) || (end > parent->end))
|
|
return ret;
|
|
|
|
/* The alloc_resource() result gets checked later */
|
|
new_res = alloc_resource(GFP_KERNEL);
|
|
|
|
p = &parent->child;
|
|
write_lock(&resource_lock);
|
|
|
|
while ((res = *p)) {
|
|
if (res->start >= end)
|
|
break;
|
|
|
|
/* look for the next resource if it does not fit into */
|
|
if (res->start > start || res->end < end) {
|
|
p = &res->sibling;
|
|
continue;
|
|
}
|
|
|
|
if (!(res->flags & IORESOURCE_MEM))
|
|
break;
|
|
|
|
if (!(res->flags & IORESOURCE_BUSY)) {
|
|
p = &res->child;
|
|
continue;
|
|
}
|
|
|
|
/* found the target resource; let's adjust accordingly */
|
|
if (res->start == start && res->end == end) {
|
|
/* free the whole entry */
|
|
*p = res->sibling;
|
|
free_resource(res);
|
|
ret = 0;
|
|
} else if (res->start == start && res->end != end) {
|
|
/* adjust the start */
|
|
ret = __adjust_resource(res, end + 1,
|
|
res->end - end);
|
|
} else if (res->start != start && res->end == end) {
|
|
/* adjust the end */
|
|
ret = __adjust_resource(res, res->start,
|
|
start - res->start);
|
|
} else {
|
|
/* split into two entries */
|
|
if (!new_res) {
|
|
ret = -ENOMEM;
|
|
break;
|
|
}
|
|
new_res->name = res->name;
|
|
new_res->start = end + 1;
|
|
new_res->end = res->end;
|
|
new_res->flags = res->flags;
|
|
new_res->parent = res->parent;
|
|
new_res->sibling = res->sibling;
|
|
new_res->child = NULL;
|
|
|
|
ret = __adjust_resource(res, res->start,
|
|
start - res->start);
|
|
if (ret)
|
|
break;
|
|
res->sibling = new_res;
|
|
new_res = NULL;
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
write_unlock(&resource_lock);
|
|
free_resource(new_res);
|
|
return ret;
|
|
}
|
|
#endif /* CONFIG_MEMORY_HOTREMOVE */
|
|
|
|
/*
|
|
* 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);
|