]>
git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/blob - drivers/hv/hv_fcopy.c
2 * An implementation of file copy service.
4 * Copyright (C) 2014, Microsoft, Inc.
6 * Author : K. Y. Srinivasan <ksrinivasan@novell.com>
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published
10 * by the Free Software Foundation.
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
15 * NON INFRINGEMENT. See the GNU General Public License for more
20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22 #include <linux/nls.h>
23 #include <linux/workqueue.h>
24 #include <linux/hyperv.h>
25 #include <linux/sched.h>
27 #include "hyperv_vmbus.h"
28 #include "hv_utils_transport.h"
30 #define WIN8_SRV_MAJOR 1
31 #define WIN8_SRV_MINOR 1
32 #define WIN8_SRV_VERSION (WIN8_SRV_MAJOR << 16 | WIN8_SRV_MINOR)
34 #define FCOPY_VER_COUNT 1
35 static const int fcopy_versions
[] = {
39 #define FW_VER_COUNT 1
40 static const int fw_versions
[] = {
45 * Global state maintained for transaction that is being processed.
46 * For a class of integration services, including the "file copy service",
47 * the specified protocol is a "request/response" protocol which means that
48 * there can only be single outstanding transaction from the host at any
49 * given point in time. We use this to simplify memory management in this
50 * driver - we cache and process only one message at a time.
52 * While the request/response protocol is guaranteed by the host, we further
53 * ensure this by serializing packet processing in this driver - we do not
54 * read additional packets from the VMBUs until the current packet is fully
59 int state
; /* hvutil_device_state */
60 int recv_len
; /* number of bytes received. */
61 struct hv_fcopy_hdr
*fcopy_msg
; /* current message */
62 struct vmbus_channel
*recv_channel
; /* chn we got the request */
63 u64 recv_req_id
; /* request ID. */
66 static void fcopy_respond_to_host(int error
);
67 static void fcopy_send_data(struct work_struct
*dummy
);
68 static void fcopy_timeout_func(struct work_struct
*dummy
);
69 static DECLARE_DELAYED_WORK(fcopy_timeout_work
, fcopy_timeout_func
);
70 static DECLARE_WORK(fcopy_send_work
, fcopy_send_data
);
71 static const char fcopy_devname
[] = "vmbus/hv_fcopy";
72 static u8
*recv_buffer
;
73 static struct hvutil_transport
*hvt
;
74 static struct completion release_event
;
76 * This state maintains the version number registered by the daemon.
78 static int dm_reg_value
;
80 static void fcopy_poll_wrapper(void *channel
)
82 /* Transaction is finished, reset the state here to avoid races. */
83 fcopy_transaction
.state
= HVUTIL_READY
;
84 hv_fcopy_onchannelcallback(channel
);
87 static void fcopy_timeout_func(struct work_struct
*dummy
)
90 * If the timer fires, the user-mode component has not responded;
91 * process the pending transaction.
93 fcopy_respond_to_host(HV_E_FAIL
);
94 hv_poll_channel(fcopy_transaction
.recv_channel
, fcopy_poll_wrapper
);
97 static void fcopy_register_done(void)
99 pr_debug("FCP: userspace daemon registered\n");
100 hv_poll_channel(fcopy_transaction
.recv_channel
, fcopy_poll_wrapper
);
103 static int fcopy_handle_handshake(u32 version
)
105 u32 our_ver
= FCOPY_CURRENT_VERSION
;
108 case FCOPY_VERSION_0
:
109 /* Daemon doesn't expect us to reply */
110 dm_reg_value
= version
;
112 case FCOPY_VERSION_1
:
113 /* Daemon expects us to reply with our own version */
114 if (hvutil_transport_send(hvt
, &our_ver
, sizeof(our_ver
),
115 fcopy_register_done
))
117 dm_reg_value
= version
;
121 * For now we will fail the registration.
122 * If and when we have multiple versions to
123 * deal with, we will be backward compatible.
124 * We will add this code when needed.
128 pr_debug("FCP: userspace daemon ver. %d connected\n", version
);
132 static void fcopy_send_data(struct work_struct
*dummy
)
134 struct hv_start_fcopy
*smsg_out
= NULL
;
135 int operation
= fcopy_transaction
.fcopy_msg
->operation
;
136 struct hv_start_fcopy
*smsg_in
;
141 * The strings sent from the host are encoded in
142 * in utf16; convert it to utf8 strings.
143 * The host assures us that the utf16 strings will not exceed
144 * the max lengths specified. We will however, reserve room
145 * for the string terminating character - in the utf16s_utf8s()
146 * function we limit the size of the buffer where the converted
147 * string is placed to W_MAX_PATH -1 to guarantee
148 * that the strings can be properly terminated!
152 case START_FILE_COPY
:
153 out_len
= sizeof(struct hv_start_fcopy
);
154 smsg_out
= kzalloc(sizeof(*smsg_out
), GFP_KERNEL
);
158 smsg_out
->hdr
.operation
= operation
;
159 smsg_in
= (struct hv_start_fcopy
*)fcopy_transaction
.fcopy_msg
;
161 utf16s_to_utf8s((wchar_t *)smsg_in
->file_name
, W_MAX_PATH
,
163 (__u8
*)&smsg_out
->file_name
, W_MAX_PATH
- 1);
165 utf16s_to_utf8s((wchar_t *)smsg_in
->path_name
, W_MAX_PATH
,
167 (__u8
*)&smsg_out
->path_name
, W_MAX_PATH
- 1);
169 smsg_out
->copy_flags
= smsg_in
->copy_flags
;
170 smsg_out
->file_size
= smsg_in
->file_size
;
175 out_src
= fcopy_transaction
.fcopy_msg
;
176 out_len
= fcopy_transaction
.recv_len
;
180 fcopy_transaction
.state
= HVUTIL_USERSPACE_REQ
;
181 rc
= hvutil_transport_send(hvt
, out_src
, out_len
, NULL
);
183 pr_debug("FCP: failed to communicate to the daemon: %d\n", rc
);
184 if (cancel_delayed_work_sync(&fcopy_timeout_work
)) {
185 fcopy_respond_to_host(HV_E_FAIL
);
186 fcopy_transaction
.state
= HVUTIL_READY
;
195 * Send a response back to the host.
199 fcopy_respond_to_host(int error
)
201 struct icmsg_hdr
*icmsghdr
;
203 struct vmbus_channel
*channel
;
207 * Copy the global state for completing the transaction. Note that
208 * only one transaction can be active at a time. This is guaranteed
209 * by the file copy protocol implemented by the host. Furthermore,
210 * the "transaction active" state we maintain ensures that there can
211 * only be one active transaction at a time.
214 buf_len
= fcopy_transaction
.recv_len
;
215 channel
= fcopy_transaction
.recv_channel
;
216 req_id
= fcopy_transaction
.recv_req_id
;
218 icmsghdr
= (struct icmsg_hdr
*)
219 &recv_buffer
[sizeof(struct vmbuspipe_hdr
)];
221 if (channel
->onchannel_callback
== NULL
)
223 * We have raced with util driver being unloaded;
228 icmsghdr
->status
= error
;
229 icmsghdr
->icflags
= ICMSGHDRFLAG_TRANSACTION
| ICMSGHDRFLAG_RESPONSE
;
230 vmbus_sendpacket(channel
, recv_buffer
, buf_len
, req_id
,
231 VM_PKT_DATA_INBAND
, 0);
234 void hv_fcopy_onchannelcallback(void *context
)
236 struct vmbus_channel
*channel
= context
;
239 struct hv_fcopy_hdr
*fcopy_msg
;
240 struct icmsg_hdr
*icmsghdr
;
241 int fcopy_srv_version
;
243 if (fcopy_transaction
.state
> HVUTIL_READY
)
246 vmbus_recvpacket(channel
, recv_buffer
, PAGE_SIZE
* 2, &recvlen
,
251 icmsghdr
= (struct icmsg_hdr
*)&recv_buffer
[
252 sizeof(struct vmbuspipe_hdr
)];
253 if (icmsghdr
->icmsgtype
== ICMSGTYPE_NEGOTIATE
) {
254 if (vmbus_prep_negotiate_resp(icmsghdr
, recv_buffer
,
255 fw_versions
, FW_VER_COUNT
,
256 fcopy_versions
, FCOPY_VER_COUNT
,
257 NULL
, &fcopy_srv_version
)) {
259 pr_info("FCopy IC version %d.%d\n",
260 fcopy_srv_version
>> 16,
261 fcopy_srv_version
& 0xFFFF);
264 fcopy_msg
= (struct hv_fcopy_hdr
*)&recv_buffer
[
265 sizeof(struct vmbuspipe_hdr
) +
266 sizeof(struct icmsg_hdr
)];
269 * Stash away this global state for completing the
270 * transaction; note transactions are serialized.
273 fcopy_transaction
.recv_len
= recvlen
;
274 fcopy_transaction
.recv_req_id
= requestid
;
275 fcopy_transaction
.fcopy_msg
= fcopy_msg
;
277 if (fcopy_transaction
.state
< HVUTIL_READY
) {
278 /* Userspace is not registered yet */
279 fcopy_respond_to_host(HV_E_FAIL
);
282 fcopy_transaction
.state
= HVUTIL_HOSTMSG_RECEIVED
;
285 * Send the information to the user-level daemon.
287 schedule_work(&fcopy_send_work
);
288 schedule_delayed_work(&fcopy_timeout_work
,
289 HV_UTIL_TIMEOUT
* HZ
);
292 icmsghdr
->icflags
= ICMSGHDRFLAG_TRANSACTION
| ICMSGHDRFLAG_RESPONSE
;
293 vmbus_sendpacket(channel
, recv_buffer
, recvlen
, requestid
,
294 VM_PKT_DATA_INBAND
, 0);
297 /* Callback when data is received from userspace */
298 static int fcopy_on_msg(void *msg
, int len
)
300 int *val
= (int *)msg
;
302 if (len
!= sizeof(int))
305 if (fcopy_transaction
.state
== HVUTIL_DEVICE_INIT
)
306 return fcopy_handle_handshake(*val
);
308 if (fcopy_transaction
.state
!= HVUTIL_USERSPACE_REQ
)
312 * Complete the transaction by forwarding the result
313 * to the host. But first, cancel the timeout.
315 if (cancel_delayed_work_sync(&fcopy_timeout_work
)) {
316 fcopy_transaction
.state
= HVUTIL_USERSPACE_RECV
;
317 fcopy_respond_to_host(*val
);
318 hv_poll_channel(fcopy_transaction
.recv_channel
,
325 static void fcopy_on_reset(void)
328 * The daemon has exited; reset the state.
330 fcopy_transaction
.state
= HVUTIL_DEVICE_INIT
;
332 if (cancel_delayed_work_sync(&fcopy_timeout_work
))
333 fcopy_respond_to_host(HV_E_FAIL
);
334 complete(&release_event
);
337 int hv_fcopy_init(struct hv_util_service
*srv
)
339 recv_buffer
= srv
->recv_buffer
;
340 fcopy_transaction
.recv_channel
= srv
->channel
;
342 init_completion(&release_event
);
344 * When this driver loads, the user level daemon that
345 * processes the host requests may not yet be running.
346 * Defer processing channel callbacks until the daemon
349 fcopy_transaction
.state
= HVUTIL_DEVICE_INIT
;
351 hvt
= hvutil_transport_init(fcopy_devname
, 0, 0,
352 fcopy_on_msg
, fcopy_on_reset
);
359 void hv_fcopy_deinit(void)
361 fcopy_transaction
.state
= HVUTIL_DEVICE_DYING
;
362 cancel_delayed_work_sync(&fcopy_timeout_work
);
363 hvutil_transport_destroy(hvt
);
364 wait_for_completion(&release_event
);