Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / staging / unisys / visorchipset / file.c

diff --git a/kernel/drivers/staging/unisys/visorchipset/file.c b/kernel/drivers/staging/unisys/visorchipset/file.c
new file mode 100644 (file)
index 0000000..203de0b
--- /dev/null
+++ b/kernel/drivers/staging/unisys/visorchipset/file.c
@@ -0,0 +1,160 @@
+/* file.c
+ *
+ * Copyright (C) 2010 - 2013 UNISYS CORPORATION
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ */
+
+/* This contains the implementation that allows a usermode program to
+ * communicate with the visorchipset driver using a device/file interface.
+ */
+
+#include "globals.h"
+#include "visorchannel.h"
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include "uisutils.h"
+#include "file.h"
+
+#define CURRENT_FILE_PC VISOR_CHIPSET_PC_file_c
+
+static struct cdev file_cdev;
+static struct visorchannel **file_controlvm_channel;
+
+void
+visorchipset_file_cleanup(dev_t major_dev)
+{
+       if (file_cdev.ops != NULL)
+               cdev_del(&file_cdev);
+       file_cdev.ops = NULL;
+       unregister_chrdev_region(major_dev, 1);
+}
+
+static int
+visorchipset_open(struct inode *inode, struct file *file)
+{
+       unsigned minor_number = iminor(inode);
+
+       if (minor_number != 0)
+               return -ENODEV;
+       file->private_data = NULL;
+       return 0;
+}
+
+static int
+visorchipset_release(struct inode *inode, struct file *file)
+{
+       return 0;
+}
+
+static int
+visorchipset_mmap(struct file *file, struct vm_area_struct *vma)
+{
+       ulong physaddr = 0;
+       ulong offset = vma->vm_pgoff << PAGE_SHIFT;
+       GUEST_PHYSICAL_ADDRESS addr = 0;
+
+       /* sv_enable_dfp(); */
+       if (offset & (PAGE_SIZE - 1))
+               return -ENXIO;  /* need aligned offsets */
+
+       switch (offset) {
+       case VISORCHIPSET_MMAP_CONTROLCHANOFFSET:
+               vma->vm_flags |= VM_IO;
+               if (*file_controlvm_channel == NULL) {
+                       return -ENXIO;
+               }
+               visorchannel_read(*file_controlvm_channel,
+                       offsetof(struct spar_controlvm_channel_protocol,
+                                gp_control_channel),
+                       &addr, sizeof(addr));
+               if (addr == 0) {
+                       return -ENXIO;
+               }
+               physaddr = (ulong)addr;
+               if (remap_pfn_range(vma, vma->vm_start,
+                                   physaddr >> PAGE_SHIFT,
+                                   vma->vm_end - vma->vm_start,
+                                   /*pgprot_noncached */
+                                   (vma->vm_page_prot))) {
+                       return -EAGAIN;
+               }
+               break;
+       default:
+               return -ENOSYS;
+       }
+       return 0;
+}
+
+static long visorchipset_ioctl(struct file *file, unsigned int cmd,
+                               unsigned long arg)
+{
+       s64 adjustment;
+       s64 vrtc_offset;
+
+       switch (cmd) {
+       case VMCALL_QUERY_GUEST_VIRTUAL_TIME_OFFSET:
+               /* get the physical rtc offset */
+               vrtc_offset = issue_vmcall_query_guest_virtual_time_offset();
+               if (copy_to_user
+                   ((void __user *)arg, &vrtc_offset, sizeof(vrtc_offset))) {
+                       return -EFAULT;
+               }
+               return SUCCESS;
+       case VMCALL_UPDATE_PHYSICAL_TIME:
+               if (copy_from_user
+                   (&adjustment, (void __user *)arg, sizeof(adjustment))) {
+                       return -EFAULT;
+               }
+               return issue_vmcall_update_physical_time(adjustment);
+       default:
+               return -EFAULT;
+       }
+}
+
+static const struct file_operations visorchipset_fops = {
+       .owner = THIS_MODULE,
+       .open = visorchipset_open,
+       .read = NULL,
+       .write = NULL,
+       .unlocked_ioctl = visorchipset_ioctl,
+       .release = visorchipset_release,
+       .mmap = visorchipset_mmap,
+};
+
+int
+visorchipset_file_init(dev_t major_dev, struct visorchannel **controlvm_channel)
+{
+       int rc = 0;
+
+       file_controlvm_channel = controlvm_channel;
+       cdev_init(&file_cdev, &visorchipset_fops);
+       file_cdev.owner = THIS_MODULE;
+       if (MAJOR(major_dev) == 0) {
+               rc = alloc_chrdev_region(&major_dev, 0, 1, MYDRVNAME);
+               /* dynamic major device number registration required */
+               if (rc < 0)
+                       return rc;
+       } else {
+               /* static major device number registration required */
+               rc = register_chrdev_region(major_dev, 1, MYDRVNAME);
+               if (rc < 0)
+                       return rc;
+       }
+       rc = cdev_add(&file_cdev, MKDEV(MAJOR(major_dev), 0), 1);
+       if (rc < 0) {
+               unregister_chrdev_region(major_dev, 1);
+               return rc;
+       }
+       return 0;
+}