sd: Use ERRP_GUARD()
[qemu.git] / hw / char / sclpconsole.c
1 /*
2 * SCLP event type
3 * Ascii Console Data (VT220 Console)
4 *
5 * Copyright IBM, Corp. 2012
6 *
7 * Authors:
8 * Heinz Graalfs <graalfs@de.ibm.com>
9 *
10 * This work is licensed under the terms of the GNU GPL, version 2 or (at your
11 * option) any later version. See the COPYING file in the top-level directory.
12 *
13 */
14
15 #include "qemu/osdep.h"
16 #include "qemu/thread.h"
17 #include "qemu/error-report.h"
18 #include "qemu/module.h"
19
20 #include "hw/s390x/sclp.h"
21 #include "migration/vmstate.h"
22 #include "hw/qdev-properties.h"
23 #include "hw/s390x/event-facility.h"
24 #include "chardev/char-fe.h"
25
26 typedef struct ASCIIConsoleData {
27 EventBufferHeader ebh;
28 char data[];
29 } QEMU_PACKED ASCIIConsoleData;
30
31 /* max size for ASCII data in 4K SCCB page */
32 #define SIZE_BUFFER_VT220 4080
33
34 typedef struct SCLPConsole {
35 SCLPEvent event;
36 CharBackend chr;
37 uint8_t iov[SIZE_BUFFER_VT220];
38 uint32_t iov_sclp; /* offset in buf for SCLP read operation */
39 uint32_t iov_bs; /* offset in buf for char layer read operation */
40 uint32_t iov_data_len; /* length of byte stream in buffer */
41 uint32_t iov_sclp_rest; /* length of byte stream not read via SCLP */
42 bool notify; /* qemu_notify_event() req'd if true */
43 } SCLPConsole;
44
45 #define TYPE_SCLP_CONSOLE "sclpconsole"
46 #define SCLP_CONSOLE(obj) \
47 OBJECT_CHECK(SCLPConsole, (obj), TYPE_SCLP_CONSOLE)
48
49 /* character layer call-back functions */
50
51 /* Return number of bytes that fit into iov buffer */
52 static int chr_can_read(void *opaque)
53 {
54 SCLPConsole *scon = opaque;
55 int avail = SIZE_BUFFER_VT220 - scon->iov_data_len;
56
57 if (avail == 0) {
58 scon->notify = true;
59 }
60 return avail;
61 }
62
63 /* Send data from a char device over to the guest */
64 static void chr_read(void *opaque, const uint8_t *buf, int size)
65 {
66 SCLPConsole *scon = opaque;
67
68 assert(scon);
69 /* read data must fit into current buffer */
70 assert(size <= SIZE_BUFFER_VT220 - scon->iov_data_len);
71
72 /* put byte-stream from character layer into buffer */
73 memcpy(&scon->iov[scon->iov_bs], buf, size);
74 scon->iov_data_len += size;
75 scon->iov_sclp_rest += size;
76 scon->iov_bs += size;
77 scon->event.event_pending = true;
78 sclp_service_interrupt(0);
79 }
80
81 /* functions to be called by event facility */
82
83 static bool can_handle_event(uint8_t type)
84 {
85 return type == SCLP_EVENT_ASCII_CONSOLE_DATA;
86 }
87
88 static sccb_mask_t send_mask(void)
89 {
90 return SCLP_EVENT_MASK_MSG_ASCII;
91 }
92
93 static sccb_mask_t receive_mask(void)
94 {
95 return SCLP_EVENT_MASK_MSG_ASCII;
96 }
97
98 /* triggered by SCLP's read_event_data -
99 * copy console data byte-stream into provided (SCLP) buffer
100 */
101 static void get_console_data(SCLPEvent *event, uint8_t *buf, size_t *size,
102 int avail)
103 {
104 SCLPConsole *cons = SCLP_CONSOLE(event);
105
106 /* first byte is hex 0 saying an ascii string follows */
107 *buf++ = '\0';
108 avail--;
109 /* if all data fit into provided SCLP buffer */
110 if (avail >= cons->iov_sclp_rest) {
111 /* copy character byte-stream to SCLP buffer */
112 memcpy(buf, &cons->iov[cons->iov_sclp], cons->iov_sclp_rest);
113 *size = cons->iov_sclp_rest + 1;
114 cons->iov_sclp = 0;
115 cons->iov_bs = 0;
116 cons->iov_data_len = 0;
117 cons->iov_sclp_rest = 0;
118 event->event_pending = false;
119 /* data provided and no more data pending */
120 } else {
121 /* if provided buffer is too small, just copy part */
122 memcpy(buf, &cons->iov[cons->iov_sclp], avail);
123 *size = avail + 1;
124 cons->iov_sclp_rest -= avail;
125 cons->iov_sclp += avail;
126 /* more data pending */
127 }
128 if (cons->notify) {
129 cons->notify = false;
130 qemu_notify_event();
131 }
132 }
133
134 static int read_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr,
135 int *slen)
136 {
137 int avail;
138 size_t src_len;
139 uint8_t *to;
140 ASCIIConsoleData *acd = (ASCIIConsoleData *) evt_buf_hdr;
141
142 if (!event->event_pending) {
143 /* no data pending */
144 return 0;
145 }
146
147 to = (uint8_t *)&acd->data;
148 avail = *slen - sizeof(ASCIIConsoleData);
149 get_console_data(event, to, &src_len, avail);
150
151 acd->ebh.length = cpu_to_be16(sizeof(ASCIIConsoleData) + src_len);
152 acd->ebh.type = SCLP_EVENT_ASCII_CONSOLE_DATA;
153 acd->ebh.flags |= SCLP_EVENT_BUFFER_ACCEPTED;
154 *slen = avail - src_len;
155
156 return 1;
157 }
158
159 /* triggered by SCLP's write_event_data
160 * - write console data to character layer
161 * returns < 0 if an error occurred
162 */
163 static ssize_t write_console_data(SCLPEvent *event, const uint8_t *buf,
164 size_t len)
165 {
166 SCLPConsole *scon = SCLP_CONSOLE(event);
167
168 if (!qemu_chr_fe_backend_connected(&scon->chr)) {
169 /* If there's no backend, we can just say we consumed all data. */
170 return len;
171 }
172
173 /* XXX this blocks entire thread. Rewrite to use
174 * qemu_chr_fe_write and background I/O callbacks */
175 return qemu_chr_fe_write_all(&scon->chr, buf, len);
176 }
177
178 static int write_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr)
179 {
180 int rc;
181 int length;
182 ssize_t written;
183 ASCIIConsoleData *acd = (ASCIIConsoleData *) evt_buf_hdr;
184
185 length = be16_to_cpu(evt_buf_hdr->length) - sizeof(EventBufferHeader);
186 written = write_console_data(event, (uint8_t *)acd->data, length);
187
188 rc = SCLP_RC_NORMAL_COMPLETION;
189 /* set event buffer accepted flag */
190 evt_buf_hdr->flags |= SCLP_EVENT_BUFFER_ACCEPTED;
191
192 /* written will be zero if a pty is not connected - don't treat as error */
193 if (written < 0) {
194 /* event buffer not accepted due to error in character layer */
195 evt_buf_hdr->flags &= ~(SCLP_EVENT_BUFFER_ACCEPTED);
196 rc = SCLP_RC_CONTAINED_EQUIPMENT_CHECK;
197 }
198
199 return rc;
200 }
201
202 static const VMStateDescription vmstate_sclpconsole = {
203 .name = "sclpconsole",
204 .version_id = 0,
205 .minimum_version_id = 0,
206 .fields = (VMStateField[]) {
207 VMSTATE_BOOL(event.event_pending, SCLPConsole),
208 VMSTATE_UINT8_ARRAY(iov, SCLPConsole, SIZE_BUFFER_VT220),
209 VMSTATE_UINT32(iov_sclp, SCLPConsole),
210 VMSTATE_UINT32(iov_bs, SCLPConsole),
211 VMSTATE_UINT32(iov_data_len, SCLPConsole),
212 VMSTATE_UINT32(iov_sclp_rest, SCLPConsole),
213 VMSTATE_END_OF_LIST()
214 }
215 };
216
217 /* qemu object creation and initialization functions */
218
219 /* tell character layer our call-back functions */
220
221 static int console_init(SCLPEvent *event)
222 {
223 static bool console_available;
224
225 SCLPConsole *scon = SCLP_CONSOLE(event);
226
227 if (console_available) {
228 error_report("Multiple VT220 operator consoles are not supported");
229 return -1;
230 }
231 console_available = true;
232 qemu_chr_fe_set_handlers(&scon->chr, chr_can_read,
233 chr_read, NULL, NULL, scon, NULL, true);
234
235 return 0;
236 }
237
238 static void console_reset(DeviceState *dev)
239 {
240 SCLPEvent *event = SCLP_EVENT(dev);
241 SCLPConsole *scon = SCLP_CONSOLE(event);
242
243 event->event_pending = false;
244 scon->iov_sclp = 0;
245 scon->iov_bs = 0;
246 scon->iov_data_len = 0;
247 scon->iov_sclp_rest = 0;
248 scon->notify = false;
249 }
250
251 static Property console_properties[] = {
252 DEFINE_PROP_CHR("chardev", SCLPConsole, chr),
253 DEFINE_PROP_END_OF_LIST(),
254 };
255
256 static void console_class_init(ObjectClass *klass, void *data)
257 {
258 DeviceClass *dc = DEVICE_CLASS(klass);
259 SCLPEventClass *ec = SCLP_EVENT_CLASS(klass);
260
261 device_class_set_props(dc, console_properties);
262 dc->reset = console_reset;
263 dc->vmsd = &vmstate_sclpconsole;
264 ec->init = console_init;
265 ec->get_send_mask = send_mask;
266 ec->get_receive_mask = receive_mask;
267 ec->can_handle_event = can_handle_event;
268 ec->read_event_data = read_event_data;
269 ec->write_event_data = write_event_data;
270 set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
271 }
272
273 static const TypeInfo sclp_console_info = {
274 .name = "sclpconsole",
275 .parent = TYPE_SCLP_EVENT,
276 .instance_size = sizeof(SCLPConsole),
277 .class_init = console_class_init,
278 .class_size = sizeof(SCLPEventClass),
279 };
280
281 static void register_types(void)
282 {
283 type_register_static(&sclp_console_info);
284 }
285
286 type_init(register_types)