drivers/virt: introduce Freescale hypervisor management driver

Add the drivers/virt directory, which houses drivers that support
virtualization environments, and add the Freescale hypervisor management
driver.

The Freescale hypervisor management driver provides several services to
drivers and applications related to the Freescale hypervisor:

1. An ioctl interface for querying and managing partitions

2. A file interface to reading incoming doorbells

3. An interrupt handler for shutting down the partition upon receiving the
   shutdown doorbell from a manager partition

4. A kernel interface for receiving callbacks when a managed partition
   shuts down.
Signed-off-by: NTimur Tabi <timur@freescale.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

Documentation/ioctl/ioctl-number.txt

@@ -301,6 +301,7 @@ Code  Seq#(hex)	Include File		Comments
 					<mailto:rusty@rustcorp.com.au>
 0xAE	all	linux/kvm.h		Kernel-based Virtual Machine
 					<mailto:kvm@vger.kernel.org>
+0xAF	00-1F	linux/fsl_hypervisor.h	Freescale hypervisor
 0xB0	all	RATIO devices		in development:
 					<mailto:vgo@ratio.de>
 0xB1	00-1F	PPPoX			<mailto:mostrows@styx.uwaterloo.ca>

drivers/Kconfig

@@ -126,4 +126,6 @@ source "drivers/hwspinlock/Kconfig"
 
 source "drivers/clocksource/Kconfig"
 
+source "drivers/virt/Kconfig"
+
 endmenu

drivers/Makefile

@@ -122,3 +122,6 @@ obj-y				+= ieee802154/
 obj-y				+= clk/
 
 obj-$(CONFIG_HWSPINLOCK)	+= hwspinlock/
+
+# Virtualization drivers
+obj-$(CONFIG_VIRT_DRIVERS)	+= virt/

drivers/virt/Kconfig

+#
+# Virtualization support drivers
+#
+
+menuconfig VIRT_DRIVERS
+	bool "Virtualization drivers"
+	---help---
+	  Say Y here to get to see options for device drivers that support
+	  virtualization environments.
+
+	  If you say N, all options in this submenu will be skipped and disabled.
+
+if VIRT_DRIVERS
+
+config FSL_HV_MANAGER
+	tristate "Freescale hypervisor management driver"
+	depends on FSL_SOC
+	help
+          The Freescale hypervisor management driver provides several services
+	  to drivers and applications related to the Freescale hypervisor:
+
+          1) An ioctl interface for querying and managing partitions.
+
+          2) A file interface to reading incoming doorbells.
+
+          3) An interrupt handler for shutting down the partition upon
+	     receiving the shutdown doorbell from a manager partition.
+
+          4) A kernel interface for receiving callbacks when a managed
+	     partition shuts down.
+
+endif

drivers/virt/Makefile

+#
+# Makefile for drivers that support virtualization
+#
+
+obj-$(CONFIG_FSL_HV_MANAGER)	+= fsl_hypervisor.o

include/linux/Kbuild

@@ -135,6 +135,7 @@ header-y += firewire-cdev.h
 header-y += firewire-constants.h
 header-y += flat.h
 header-y += fs.h
+header-y += fsl_hypervisor.h
 header-y += fuse.h
 header-y += futex.h
 header-y += gameport.h

include/linux/fsl_hypervisor.h

+/*
+ * Freescale hypervisor ioctl and kernel interface
+ *
+ * Copyright (C) 2008-2011 Freescale Semiconductor, Inc.
+ * Author: Timur Tabi <timur@freescale.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of Freescale Semiconductor nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ *
+ * ALTERNATIVELY, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") as published by the Free Software
+ * Foundation, either version 2 of that License or (at your option) any
+ * later version.
+ *
+ * This software is provided by Freescale Semiconductor "as is" and any
+ * express or implied warranties, including, but not limited to, the implied
+ * warranties of merchantability and fitness for a particular purpose are
+ * disclaimed. In no event shall Freescale Semiconductor be liable for any
+ * direct, indirect, incidental, special, exemplary, or consequential damages
+ * (including, but not limited to, procurement of substitute goods or services;
+ * loss of use, data, or profits; or business interruption) however caused and
+ * on any theory of liability, whether in contract, strict liability, or tort
+ * (including negligence or otherwise) arising in any way out of the use of this
+ * software, even if advised of the possibility of such damage.
+ *
+ * This file is used by the Freescale hypervisor management driver.  It can
+ * also be included by applications that need to communicate with the driver
+ * via the ioctl interface.
+ */
+
+#ifndef FSL_HYPERVISOR_H
+#define FSL_HYPERVISOR_H
+
+#include <linux/types.h>
+
+/**
+ * struct fsl_hv_ioctl_restart - restart a partition
+ * @ret: return error code from the hypervisor
+ * @partition: the ID of the partition to restart, or -1 for the
+ *             calling partition
+ *
+ * Used by FSL_HV_IOCTL_PARTITION_RESTART
+ */
+struct fsl_hv_ioctl_restart {
+	__u32 ret;
+	__u32 partition;
+};
+
+/**
+ * struct fsl_hv_ioctl_status - get a partition's status
+ * @ret: return error code from the hypervisor
+ * @partition: the ID of the partition to query, or -1 for the
+ *             calling partition
+ * @status: The returned status of the partition
+ *
+ * Used by FSL_HV_IOCTL_PARTITION_GET_STATUS
+ *
+ * Values of 'status':
+ *    0 = Stopped
+ *    1 = Running
+ *    2 = Starting
+ *    3 = Stopping
+ */
+struct fsl_hv_ioctl_status {
+	__u32 ret;
+	__u32 partition;
+	__u32 status;
+};
+
+/**
+ * struct fsl_hv_ioctl_start - start a partition
+ * @ret: return error code from the hypervisor
+ * @partition: the ID of the partition to control
+ * @entry_point: The offset within the guest IMA to start execution
+ * @load: If non-zero, reload the partition's images before starting
+ *
+ * Used by FSL_HV_IOCTL_PARTITION_START
+ */
+struct fsl_hv_ioctl_start {
+	__u32 ret;
+	__u32 partition;
+	__u32 entry_point;
+	__u32 load;
+};
+
+/**
+ * struct fsl_hv_ioctl_stop - stop a partition
+ * @ret: return error code from the hypervisor
+ * @partition: the ID of the partition to stop, or -1 for the calling
+ *             partition
+ *
+ * Used by FSL_HV_IOCTL_PARTITION_STOP
+ */
+struct fsl_hv_ioctl_stop {
+	__u32 ret;
+	__u32 partition;
+};
+
+/**
+ * struct fsl_hv_ioctl_memcpy - copy memory between partitions
+ * @ret: return error code from the hypervisor
+ * @source: the partition ID of the source partition, or -1 for this
+ *          partition
+ * @target: the partition ID of the target partition, or -1 for this
+ *          partition
+ * @reserved: reserved, must be set to 0
+ * @local_addr: user-space virtual address of a buffer in the local
+ *              partition
+ * @remote_addr: guest physical address of a buffer in the
+ *           remote partition
+ * @count: the number of bytes to copy.  Both the local and remote
+ *         buffers must be at least 'count' bytes long
+ *
+ * Used by FSL_HV_IOCTL_MEMCPY
+ *
+ * The 'local' partition is the partition that calls this ioctl.  The
+ * 'remote' partition is a different partition.  The data is copied from
+ * the 'source' paritition' to the 'target' partition.
+ *
+ * The buffer in the remote partition must be guest physically
+ * contiguous.
+ *
+ * This ioctl does not support copying memory between two remote
+ * partitions or within the same partition, so either 'source' or
+ * 'target' (but not both) must be -1.  In other words, either
+ *
+ *      source == local and target == remote
+ * or
+ *      source == remote and target == local
+ */
+struct fsl_hv_ioctl_memcpy {
+	__u32 ret;
+	__u32 source;
+	__u32 target;
+	__u32 reserved;	/* padding to ensure local_vaddr is aligned */
+	__u64 local_vaddr;
+	__u64 remote_paddr;
+	__u64 count;
+};
+
+/**
+ * struct fsl_hv_ioctl_doorbell - ring a doorbell
+ * @ret: return error code from the hypervisor
+ * @doorbell: the handle of the doorbell to ring doorbell
+ *
+ * Used by FSL_HV_IOCTL_DOORBELL
+ */
+struct fsl_hv_ioctl_doorbell {
+	__u32 ret;
+	__u32 doorbell;
+};
+
+/**
+ * struct fsl_hv_ioctl_prop - get/set a device tree property
+ * @ret: return error code from the hypervisor
+ * @handle: handle of partition whose tree to access
+ * @path: virtual address of path name of node to access
+ * @propname: virtual address of name of property to access
+ * @propval: virtual address of property data buffer
+ * @proplen: Size of property data buffer
+ * @reserved: reserved, must be set to 0
+ *
+ * Used by FSL_HV_IOCTL_DOORBELL
+ */
+struct fsl_hv_ioctl_prop {
+	__u32 ret;
+	__u32 handle;
+	__u64 path;
+	__u64 propname;
+	__u64 propval;
+	__u32 proplen;
+	__u32 reserved;	/* padding to ensure structure is aligned */
+};
+
+/* The ioctl type, documented in ioctl-number.txt */
+#define FSL_HV_IOCTL_TYPE	0xAF
+
+/* Restart another partition */
+#define FSL_HV_IOCTL_PARTITION_RESTART \
+	_IOWR(FSL_HV_IOCTL_TYPE, 1, struct fsl_hv_ioctl_restart)
+
+/* Get a partition's status */
+#define FSL_HV_IOCTL_PARTITION_GET_STATUS \
+	_IOWR(FSL_HV_IOCTL_TYPE, 2, struct fsl_hv_ioctl_status)
+
+/* Boot another partition */
+#define FSL_HV_IOCTL_PARTITION_START \
+	_IOWR(FSL_HV_IOCTL_TYPE, 3, struct fsl_hv_ioctl_start)
+
+/* Stop this or another partition */
+#define FSL_HV_IOCTL_PARTITION_STOP \
+	_IOWR(FSL_HV_IOCTL_TYPE, 4, struct fsl_hv_ioctl_stop)
+
+/* Copy data from one partition to another */
+#define FSL_HV_IOCTL_MEMCPY \
+	_IOWR(FSL_HV_IOCTL_TYPE, 5, struct fsl_hv_ioctl_memcpy)
+
+/* Ring a doorbell */
+#define FSL_HV_IOCTL_DOORBELL \
+	_IOWR(FSL_HV_IOCTL_TYPE, 6, struct fsl_hv_ioctl_doorbell)
+
+/* Get a property from another guest's device tree */
+#define FSL_HV_IOCTL_GETPROP \
+	_IOWR(FSL_HV_IOCTL_TYPE, 7, struct fsl_hv_ioctl_prop)
+
+/* Set a property in another guest's device tree */
+#define FSL_HV_IOCTL_SETPROP \
+	_IOWR(FSL_HV_IOCTL_TYPE, 8, struct fsl_hv_ioctl_prop)
+
+#ifdef __KERNEL__
+
+/**
+ * fsl_hv_event_register() - register a callback for failover events
+ * @nb: pointer to caller-supplied notifier_block structure
+ *
+ * This function is called by device drivers to register their callback
+ * functions for fail-over events.
+ *
+ * The caller should allocate a notifier_block object and initialize the
+ * 'priority' and 'notifier_call' fields.
+ */
+int fsl_hv_failover_register(struct notifier_block *nb);
+
+/**
+ * fsl_hv_event_unregister() - unregister a callback for failover events
+ * @nb: the same 'nb' used in previous fsl_hv_failover_register call
+ */
+int fsl_hv_failover_unregister(struct notifier_block *nb);
+
+#endif
+
+#endif