1 files changed, 145 insertions, 0 deletions
diff --git a/linux/dev/kernel/resource.c b/linux/dev/kernel/resource.c
new file mode 100644
index 0000000..7a18755
--- /dev/null
+++ b/linux/dev/kernel/resource.c
@@ -0,0 +1,145 @@
+/*
+ *	linux/kernel/resource.c
+ *
+ * Copyright (C) 1995	Linus Torvalds
+ *			David Hinds
+ *
+ * Kernel io-region resource management
+ */
+
+#include <sys/types.h>
+
+#define MACH_INCLUDE
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/ioport.h>
+
+#define IOTABLE_SIZE 128
+
+typedef struct resource_entry_t
+{
+  u_long from, num;
+  const char *name;
+  struct resource_entry_t *next;
+} resource_entry_t;
+
+static resource_entry_t iolist = { 0, 0, "", NULL };
+
+static resource_entry_t iotable[IOTABLE_SIZE];
+
+/*
+ * This generates the report for /proc/ioports
+ */
+#ifndef MACH
+int
+get_ioport_list (char *buf)
+{
+  resource_entry_t *p;
+  int len = 0;
+  
+  for (p = iolist.next; (p) && (len < 4000); p = p->next)
+    len += linux_sprintf (buf+len, "%04lx-%04lx : %s\n",
+			  p->from, p->from+p->num-1, p->name);
+  if (p)
+    len += linux_sprintf (buf+len, "4K limit reached!\n");
+  return len;
+}
+#endif
+
+/*
+ * The workhorse function: find where to put a new entry
+ */
+static resource_entry_t *
+find_gap (resource_entry_t *root, u_long from, u_long num)
+{
+  unsigned long flags;
+  resource_entry_t *p;
+  
+  if (from > from+num-1)
+    return NULL;
+  save_flags (flags);
+  cli ();
+  for (p = root; ; p = p->next)
+    {
+      if ((p != root) && (p->from+p->num-1 >= from))
+	{
+	  p = NULL;
+	  break;
+	}
+      if ((p->next == NULL) || (p->next->from > from+num-1))
+	break;
+    }
+  restore_flags (flags);
+  return p;
+}
+
+/*
+ * Call this from the device driver to register the ioport region.
+ */
+void
+request_region (unsigned int from, unsigned int num, const char *name)
+{
+  resource_entry_t *p;
+  int i;
+  
+  for (i = 0; i < IOTABLE_SIZE; i++)
+    if (iotable[i].num == 0)
+      break;
+  if (i == IOTABLE_SIZE)
+    printk ("warning: ioport table is full\n");
+  else
+    {
+      p = find_gap (&iolist, from, num);
+      if (p == NULL)
+	return;
+      iotable[i].name = name;
+      iotable[i].from = from;
+      iotable[i].num = num;
+      iotable[i].next = p->next;
+      p->next = &iotable[i];
+      return;
+    }
+}
+
+/* 
+ * Call this when the device driver is unloaded
+ */
+void
+release_region (unsigned int from, unsigned int num)
+{
+  resource_entry_t *p, *q;
+  
+  for (p = &iolist; ; p = q)
+    {
+      q = p->next;
+      if (q == NULL)
+	break;
+      if ((q->from == from) && (q->num == num))
+	{
+	  q->num = 0;
+	  p->next = q->next;
+	  return;
+	}
+    }
+}
+
+/*
+ * Call this to check the ioport region before probing
+ */
+int
+check_region (unsigned int from, unsigned int num)
+{
+  return (find_gap (&iolist, from, num) == NULL) ? -LINUX_EBUSY : 0;
+}
+
+/* Called from init/main.c to reserve IO ports. */
+void
+reserve_setup(char *str, int *ints)
+{
+  int i;
+  
+  for (i = 1; i < ints[0]; i += 2)
+    request_region (ints[i], ints[i+1], "reserved");
+}