1 files changed, 551 insertions, 0 deletions

diff --git a/kernel/resource.c b/kernel/resource.c
new file mode 100644
index 000000000000..35c99ac02c7c
--- /dev/null
+++ b/kernel/resource.c
@@ -0,0 +1,551 @@
+/*
+ *      linux/kernel/resource.c
+ *
+ * Copyright (C) 1999   Linus Torvalds
+ * Copyright (C) 1999   Martin Mares <mj@ucw.cz>
+ *
+ * Arbitrary resource management.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/sched.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 <asm/io.h>
+
+
+struct resource ioport_resource = {
+        .name   = "PCI IO",
+        .start  = 0x0000,
+        .end    = IO_SPACE_LIMIT,
+        .flags  = IORESOURCE_IO,
+};
+
+EXPORT_SYMBOL(ioport_resource);
+
+struct resource iomem_resource = {
+        .name   = "PCI mem",
+        .start  = 0UL,
+        .end    = ~0UL,
+        .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*lx-%0*lx : %s\n",
+                        depth * 2, "",
+                        width, r->start,
+                        width, r->end,
+                        r->name ? r->name : "<BAD>");
+        return 0;
+}
+
+static 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 struct file_operations proc_ioports_operations = {
+        .open           = ioports_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = seq_release,
+};
+
+static struct file_operations proc_iomem_operations = {
+        .open           = iomem_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = seq_release,
+};
+
+static int __init ioresources_init(void)
+{
+        struct proc_dir_entry *entry;
+
+        entry = create_proc_entry("ioports", 0, NULL);
+        if (entry)
+                entry->proc_fops = &proc_ioports_operations;
+        entry = create_proc_entry("iomem", 0, NULL);
+        if (entry)
+                entry->proc_fops = &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)
+{
+        unsigned long start = new->start;
+        unsigned long 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;
+}
+
+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);
+
+struct resource *____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;
+}
+
+EXPORT_SYMBOL(____request_resource);
+
+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);
+
+/*
+ * Find empty slot in the resource tree given range and alignment.
+ */
+static int find_resource(struct resource *root, struct resource *new,
+                         unsigned long size,
+                         unsigned long min, unsigned long max,
+                         unsigned long align,
+                         void (*alignf)(void *, struct resource *,
+                                        unsigned long, unsigned long),
+                         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 = (new->start + align - 1) & ~(align - 1);
+                if (alignf)
+                        alignf(alignf_data, new, size, align);
+                if (new->start < new->end && new->end - new->start + 1 >= size) {
+                        new->end = new->start + size - 1;
+                        return 0;
+                }
+                if (!this)
+                        break;
+                new->start = this->end + 1;
+                this = this->sibling;
+        }
+        return -EBUSY;
+}
+
+/*
+ * Allocate empty slot in the resource tree given range and alignment.
+ */
+int allocate_resource(struct resource *root, struct resource *new,
+                      unsigned long size,
+                      unsigned long min, unsigned long max,
+                      unsigned long align,
+                      void (*alignf)(void *, struct resource *,
+                                     unsigned long, unsigned long),
+                      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 of 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 childs of
+ * the new resource.  Otherwise the new resource becomes the child of
+ * the conflicting resource
+ */
+int insert_resource(struct resource *parent, struct resource *new)
+{
+        int result;
+        struct resource *first, *next;
+
+        write_lock(&resource_lock);
+ begin:
+        result = 0;
+        first = __request_resource(parent, new);
+        if (!first)
+                goto out;
+
+        result = -EBUSY;
+        if (first == parent)
+                goto out;
+
+        /* Resource fully contained by the clashing resource? Recurse into it */
+        if (first->start <= new->start && first->end >= new->end) {
+                parent = first;
+                goto begin;
+        }
+
+        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;
+}
+
+EXPORT_SYMBOL(insert_resource);
+
+/*
+ * Given an existing resource, change its start and size to match the
+ * arguments.  Returns -EBUSY if it can't fit.  Existing children of
+ * the resource are assumed to be immutable.
+ */
+int adjust_resource(struct resource *res, unsigned long start, unsigned long size)
+{
+        struct resource *tmp, *parent = res->parent;
+        unsigned long 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);
+
+/*
+ * 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.
+ */
+struct resource * __request_region(struct resource *parent, unsigned long start, unsigned long n, const char *name)
+{
+        struct resource *res = kmalloc(sizeof(*res), GFP_KERNEL);
+
+        if (res) {
+                memset(res, 0, sizeof(*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);
+
+int __deprecated __check_region(struct resource *parent, unsigned long start, unsigned long 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);
+
+void __release_region(struct resource *parent, unsigned long start, unsigned long n)
+{
+        struct resource **p;
+        unsigned long 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 <%08lx-%08lx>\n", start, end);
+}
+
+EXPORT_SYMBOL(__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);