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Diffstat (limited to 'arch/um/drivers/mmapper_kern.c')
-rw-r--r--arch/um/drivers/mmapper_kern.c150
1 files changed, 150 insertions, 0 deletions
diff --git a/arch/um/drivers/mmapper_kern.c b/arch/um/drivers/mmapper_kern.c
new file mode 100644
index 00000000000..a63231dffe0
--- /dev/null
+++ b/arch/um/drivers/mmapper_kern.c
@@ -0,0 +1,150 @@
+/*
+ * arch/um/drivers/mmapper_kern.c
+ *
+ * BRIEF MODULE DESCRIPTION
+ *
+ * Copyright (C) 2000 RidgeRun, Inc.
+ * Author: RidgeRun, Inc.
+ * Greg Lonnon glonnon@ridgerun.com or info@ridgerun.com
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/kdev_t.h>
+#include <linux/time.h>
+#include <linux/devfs_fs_kernel.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/smp_lock.h>
+#include <asm/uaccess.h>
+#include <asm/irq.h>
+#include <asm/pgtable.h>
+#include "mem_user.h"
+#include "user_util.h"
+
+/* These are set in mmapper_init, which is called at boot time */
+static unsigned long mmapper_size;
+static unsigned long p_buf = 0;
+static char *v_buf = NULL;
+
+static ssize_t
+mmapper_read(struct file *file, char *buf, size_t count, loff_t *ppos)
+{
+ if(*ppos > mmapper_size)
+ return -EINVAL;
+
+ if(count + *ppos > mmapper_size)
+ count = count + *ppos - mmapper_size;
+
+ if(count < 0)
+ return -EINVAL;
+
+ copy_to_user(buf,&v_buf[*ppos],count);
+
+ return count;
+}
+
+static ssize_t
+mmapper_write(struct file *file, const char *buf, size_t count, loff_t *ppos)
+{
+ if(*ppos > mmapper_size)
+ return -EINVAL;
+
+ if(count + *ppos > mmapper_size)
+ count = count + *ppos - mmapper_size;
+
+ if(count < 0)
+ return -EINVAL;
+
+ copy_from_user(&v_buf[*ppos],buf,count);
+
+ return count;
+}
+
+static int
+mmapper_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ return(-ENOIOCTLCMD);
+}
+
+static int
+mmapper_mmap(struct file *file, struct vm_area_struct * vma)
+{
+ int ret = -EINVAL;
+ int size;
+
+ lock_kernel();
+ if (vma->vm_pgoff != 0)
+ goto out;
+
+ size = vma->vm_end - vma->vm_start;
+ if(size > mmapper_size) return(-EFAULT);
+
+ /* XXX A comment above remap_pfn_range says it should only be
+ * called when the mm semaphore is held
+ */
+ if (remap_pfn_range(vma, vma->vm_start, p_buf >> PAGE_SHIFT, size,
+ vma->vm_page_prot))
+ goto out;
+ ret = 0;
+out:
+ unlock_kernel();
+ return ret;
+}
+
+static int
+mmapper_open(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+
+static int
+mmapper_release(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+
+static struct file_operations mmapper_fops = {
+ .owner = THIS_MODULE,
+ .read = mmapper_read,
+ .write = mmapper_write,
+ .ioctl = mmapper_ioctl,
+ .mmap = mmapper_mmap,
+ .open = mmapper_open,
+ .release = mmapper_release,
+};
+
+static int __init mmapper_init(void)
+{
+ printk(KERN_INFO "Mapper v0.1\n");
+
+ v_buf = (char *) find_iomem("mmapper", &mmapper_size);
+ if(mmapper_size == 0){
+ printk(KERN_ERR "mmapper_init - find_iomem failed\n");
+ return(0);
+ }
+
+ p_buf = __pa(v_buf);
+
+ devfs_mk_cdev(MKDEV(30, 0), S_IFCHR|S_IRUGO|S_IWUGO, "mmapper");
+ return(0);
+}
+
+static void mmapper_exit(void)
+{
+}
+
+module_init(mmapper_init);
+module_exit(mmapper_exit);
+
+MODULE_AUTHOR("Greg Lonnon <glonnon@ridgerun.com>");
+MODULE_DESCRIPTION("DSPLinux simulator mmapper driver");
+/*
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */