1 files changed, 344 insertions, 0 deletions

diff --git a/include/linux/visorbus.h b/include/linux/visorbus.h
new file mode 100644
index 000000000000..0d8bd6769b13
--- /dev/null
+++ b/include/linux/visorbus.h
@@ -0,0 +1,344 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2010 - 2013 UNISYS CORPORATION
+ * All rights reserved.
+ */
+
+/*
+ *  This header file is to be included by other kernel mode components that
+ *  implement a particular kind of visor_device.  Each of these other kernel
+ *  mode components is called a visor device driver.  Refer to visortemplate
+ *  for a minimal sample visor device driver.
+ *
+ *  There should be nothing in this file that is private to the visorbus
+ *  bus implementation itself.
+ */
+
+#ifndef __VISORBUS_H__
+#define __VISORBUS_H__
+
+#include <linux/device.h>
+
+#define VISOR_CHANNEL_SIGNATURE ('L' << 24 | 'N' << 16 | 'C' << 8 | 'E')
+
+/*
+ * enum channel_serverstate
+ * @CHANNELSRV_UNINITIALIZED: Channel is in an undefined state.
+ * @CHANNELSRV_READY:         Channel has been initialized by server.
+ */
+enum channel_serverstate {
+        CHANNELSRV_UNINITIALIZED = 0,
+        CHANNELSRV_READY = 1
+};
+
+/*
+ * enum channel_clientstate
+ * @CHANNELCLI_DETACHED:
+ * @CHANNELCLI_DISABLED:  Client can see channel but is NOT allowed to use it
+ *                        unless given TBD* explicit request
+ *                        (should actually be < DETACHED).
+ * @CHANNELCLI_ATTACHING: Legacy EFI client request for EFI server to attach.
+ * @CHANNELCLI_ATTACHED:  Idle, but client may want to use channel any time.
+ * @CHANNELCLI_BUSY:      Client either wants to use or is using channel.
+ * @CHANNELCLI_OWNED:     "No worries" state - client can access channel
+ *                        anytime.
+ */
+enum channel_clientstate {
+        CHANNELCLI_DETACHED = 0,
+        CHANNELCLI_DISABLED = 1,
+        CHANNELCLI_ATTACHING = 2,
+        CHANNELCLI_ATTACHED = 3,
+        CHANNELCLI_BUSY = 4,
+        CHANNELCLI_OWNED = 5
+};
+
+/*
+ * Values for VISOR_CHANNEL_PROTOCOL.Features: This define exists so that
+ * a guest can look at the FeatureFlags in the io channel, and configure the
+ * driver to use interrupts or not based on this setting. All feature bits for
+ * all channels should be defined here. The io channel feature bits are defined
+ * below.
+ */
+#define VISOR_DRIVER_ENABLES_INTS (0x1ULL << 1)
+#define VISOR_CHANNEL_IS_POLLING (0x1ULL << 3)
+#define VISOR_IOVM_OK_DRIVER_DISABLING_INTS (0x1ULL << 4)
+#define VISOR_DRIVER_DISABLES_INTS (0x1ULL << 5)
+#define VISOR_DRIVER_ENHANCED_RCVBUF_CHECKING (0x1ULL << 6)
+
+/*
+ * struct channel_header - Common Channel Header
+ * @signature:         Signature.
+ * @legacy_state:      DEPRECATED - being replaced by.
+ * @header_size:       sizeof(struct channel_header).
+ * @size:              Total size of this channel in bytes.
+ * @features:          Flags to modify behavior.
+ * @chtype:            Channel type: data, bus, control, etc..
+ * @partition_handle:  ID of guest partition.
+ * @handle:            Device number of this channel in client.
+ * @ch_space_offset:   Offset in bytes to channel specific area.
+ * @version_id:        Struct channel_header Version ID.
+ * @partition_index:   Index of guest partition.
+ * @zone_uuid:         Guid of Channel's zone.
+ * @cli_str_offset:    Offset from channel header to null-terminated
+ *                     ClientString (0 if ClientString not present).
+ * @cli_state_boot:    CHANNEL_CLIENTSTATE of pre-boot EFI client of this
+ *                     channel.
+ * @cmd_state_cli:     CHANNEL_COMMANDSTATE (overloaded in Windows drivers, see
+ *                     ServerStateUp, ServerStateDown, etc).
+ * @cli_state_os:      CHANNEL_CLIENTSTATE of Guest OS client of this channel.
+ * @ch_characteristic: CHANNEL_CHARACTERISTIC_<xxx>.
+ * @cmd_state_srv:     CHANNEL_COMMANDSTATE (overloaded in Windows drivers, see
+ *                     ServerStateUp, ServerStateDown, etc).
+ * @srv_state:         CHANNEL_SERVERSTATE.
+ * @cli_error_boot:    Bits to indicate err states for boot clients, so err
+ *                     messages can be throttled.
+ * @cli_error_os:      Bits to indicate err states for OS clients, so err
+ *                     messages can be throttled.
+ * @filler:            Pad out to 128 byte cacheline.
+ * @recover_channel:   Please add all new single-byte values below here.
+ */
+struct channel_header {
+        u64 signature;
+        u32 legacy_state;
+        /* SrvState, CliStateBoot, and CliStateOS below */
+        u32 header_size;
+        u64 size;
+        u64 features;
+        guid_t chtype;
+        u64 partition_handle;
+        u64 handle;
+        u64 ch_space_offset;
+        u32 version_id;
+        u32 partition_index;
+        guid_t zone_guid;
+        u32 cli_str_offset;
+        u32 cli_state_boot;
+        u32 cmd_state_cli;
+        u32 cli_state_os;
+        u32 ch_characteristic;
+        u32 cmd_state_srv;
+        u32 srv_state;
+        u8 cli_error_boot;
+        u8 cli_error_os;
+        u8 filler[1];
+        u8 recover_channel;
+} __packed;
+
+#define VISOR_CHANNEL_ENABLE_INTS (0x1ULL << 0)
+
+/*
+ * struct signal_queue_header - Subheader for the Signal Type variation of the
+ *                              Common Channel.
+ * @version:          SIGNAL_QUEUE_HEADER Version ID.
+ * @chtype:           Queue type: storage, network.
+ * @size:             Total size of this queue in bytes.
+ * @sig_base_offset:  Offset to signal queue area.
+ * @features:         Flags to modify behavior.
+ * @num_sent:         Total # of signals placed in this queue.
+ * @num_overflows:    Total # of inserts failed due to full queue.
+ * @signal_size:      Total size of a signal for this queue.
+ * @max_slots:        Max # of slots in queue, 1 slot is always empty.
+ * @max_signals:      Max # of signals in queue (MaxSignalSlots-1).
+ * @head:             Queue head signal #.
+ * @num_received:     Total # of signals removed from this queue.
+ * @tail:             Queue tail signal.
+ * @reserved1:        Reserved field.
+ * @reserved2:        Reserved field.
+ * @client_queue:
+ * @num_irq_received: Total # of Interrupts received. This is incremented by the
+ *                    ISR in the guest windows driver.
+ * @num_empty:        Number of times that visor_signal_remove is called and
+ *                    returned Empty Status.
+ * @errorflags:       Error bits set during SignalReinit to denote trouble with
+ *                    client's fields.
+ * @filler:           Pad out to 64 byte cacheline.
+ */
+struct signal_queue_header {
+        /* 1st cache line */
+        u32 version;
+        u32 chtype;
+        u64 size;
+        u64 sig_base_offset;
+        u64 features;
+        u64 num_sent;
+        u64 num_overflows;
+        u32 signal_size;
+        u32 max_slots;
+        u32 max_signals;
+        u32 head;
+        /* 2nd cache line */
+        u64 num_received;
+        u32 tail;
+        u32 reserved1;
+        u64 reserved2;
+        u64 client_queue;
+        u64 num_irq_received;
+        u64 num_empty;
+        u32 errorflags;
+        u8 filler[12];
+} __packed;
+
+/* VISORCHANNEL Guids */
+/* {414815ed-c58c-11da-95a9-00e08161165f} */
+#define VISOR_VHBA_CHANNEL_GUID \
+        GUID_INIT(0x414815ed, 0xc58c, 0x11da, \
+                  0x95, 0xa9, 0x0, 0xe0, 0x81, 0x61, 0x16, 0x5f)
+#define VISOR_VHBA_CHANNEL_GUID_STR \
+        "414815ed-c58c-11da-95a9-00e08161165f"
+struct visorchipset_state {
+        u32 created:1;
+        u32 attached:1;
+        u32 configured:1;
+        u32 running:1;
+        /* Remaining bits in this 32-bit word are reserved. */
+};
+
+/**
+ * struct visor_device - A device type for things "plugged" into the visorbus
+ *                       bus
+ * @visorchannel:               Points to the channel that the device is
+ *                              associated with.
+ * @channel_type_guid:          Identifies the channel type to the bus driver.
+ * @device:                     Device struct meant for use by the bus driver
+ *                              only.
+ * @list_all:                   Used by the bus driver to enumerate devices.
+ * @timer:                      Timer fired periodically to do interrupt-type
+ *                              activity.
+ * @being_removed:              Indicates that the device is being removed from
+ *                              the bus. Private bus driver use only.
+ * @visordriver_callback_lock:  Used by the bus driver to lock when adding and
+ *                              removing devices.
+ * @pausing:                    Indicates that a change towards a paused state.
+ *                              is in progress. Only modified by the bus driver.
+ * @resuming:                   Indicates that a change towards a running state
+ *                              is in progress. Only modified by the bus driver.
+ * @chipset_bus_no:             Private field used by the bus driver.
+ * @chipset_dev_no:             Private field used the bus driver.
+ * @state:                      Used to indicate the current state of the
+ *                              device.
+ * @inst:                       Unique GUID for this instance of the device.
+ * @name:                       Name of the device.
+ * @pending_msg_hdr:            For private use by bus driver to respond to
+ *                              hypervisor requests.
+ * @vbus_hdr_info:              A pointer to header info. Private use by bus
+ *                              driver.
+ * @partition_guid:             Indicates client partion id. This should be the
+ *                              same across all visor_devices in the current
+ *                              guest. Private use by bus driver only.
+ */
+struct visor_device {
+        struct visorchannel *visorchannel;
+        guid_t channel_type_guid;
+        /* These fields are for private use by the bus driver only. */
+        struct device device;
+        struct list_head list_all;
+        struct timer_list timer;
+        bool timer_active;
+        bool being_removed;
+        struct mutex visordriver_callback_lock; /* synchronize probe/remove */
+        bool pausing;
+        bool resuming;
+        u32 chipset_bus_no;
+        u32 chipset_dev_no;
+        struct visorchipset_state state;
+        guid_t inst;
+        u8 *name;
+        struct controlvm_message_header *pending_msg_hdr;
+        void *vbus_hdr_info;
+        guid_t partition_guid;
+        struct dentry *debugfs_dir;
+        struct dentry *debugfs_bus_info;
+};
+
+#define to_visor_device(x) container_of(x, struct visor_device, device)
+
+typedef void (*visorbus_state_complete_func) (struct visor_device *dev,
+                                              int status);
+
+/*
+ * This struct describes a specific visor channel, by providing its GUID, name,
+ * and sizes.
+ */
+struct visor_channeltype_descriptor {
+        const guid_t guid;
+        const char *name;
+        u64 min_bytes;
+        u32 version;
+};
+
+/**
+ * struct visor_driver - Information provided by each visor driver when it
+ *                       registers with the visorbus driver
+ * @name:               Name of the visor driver.
+ * @owner:              The module owner.
+ * @channel_types:      Types of channels handled by this driver, ending with
+ *                      a zero GUID. Our specialized BUS.match() method knows
+ *                      about this list, and uses it to determine whether this
+ *                      driver will in fact handle a new device that it has
+ *                      detected.
+ * @probe:              Called when a new device comes online, by our probe()
+ *                      function specified by driver.probe() (triggered
+ *                      ultimately by some call to driver_register(),
+ *                      bus_add_driver(), or driver_attach()).
+ * @remove:             Called when a new device is removed, by our remove()
+ *                      function specified by driver.remove() (triggered
+ *                      ultimately by some call to device_release_driver()).
+ * @channel_interrupt:  Called periodically, whenever there is a possiblity
+ *                      that "something interesting" may have happened to the
+ *                      channel.
+ * @pause:              Called to initiate a change of the device's state.  If
+ *                      the return valu`e is < 0, there was an error and the
+ *                      state transition will NOT occur.  If the return value
+ *                      is >= 0, then the state transition was INITIATED
+ *                      successfully, and complete_func() will be called (or
+ *                      was just called) with the final status when either the
+ *                      state transition fails or completes successfully.
+ * @resume:             Behaves similar to pause.
+ * @driver:             Private reference to the device driver. For use by bus
+ *                      driver only.
+ */
+struct visor_driver {
+        const char *name;
+        struct module *owner;
+        struct visor_channeltype_descriptor *channel_types;
+        int (*probe)(struct visor_device *dev);
+        void (*remove)(struct visor_device *dev);
+        void (*channel_interrupt)(struct visor_device *dev);
+        int (*pause)(struct visor_device *dev,
+                     visorbus_state_complete_func complete_func);
+        int (*resume)(struct visor_device *dev,
+                      visorbus_state_complete_func complete_func);
+
+        /* These fields are for private use by the bus driver only. */
+        struct device_driver driver;
+};
+
+#define to_visor_driver(x) (container_of(x, struct visor_driver, driver))
+
+int visor_check_channel(struct channel_header *ch, struct device *dev,
+                        const guid_t *expected_uuid, char *chname,
+                        u64 expected_min_bytes, u32 expected_version,
+                        u64 expected_signature);
+
+int visorbus_register_visor_driver(struct visor_driver *drv);
+void visorbus_unregister_visor_driver(struct visor_driver *drv);
+int visorbus_read_channel(struct visor_device *dev,
+                          unsigned long offset, void *dest,
+                          unsigned long nbytes);
+int visorbus_write_channel(struct visor_device *dev,
+                           unsigned long offset, void *src,
+                           unsigned long nbytes);
+int visorbus_enable_channel_interrupts(struct visor_device *dev);
+void visorbus_disable_channel_interrupts(struct visor_device *dev);
+
+int visorchannel_signalremove(struct visorchannel *channel, u32 queue,
+                              void *msg);
+int visorchannel_signalinsert(struct visorchannel *channel, u32 queue,
+                              void *msg);
+bool visorchannel_signalempty(struct visorchannel *channel, u32 queue);
+const guid_t *visorchannel_get_guid(struct visorchannel *channel);
+
+#define BUS_ROOT_DEVICE UINT_MAX
+struct visor_device *visorbus_get_device_by_id(u32 bus_no, u32 dev_no,
+                                               struct visor_device *from);
+#endif