xref: /openbmc/linux/drivers/s390/char/sclp_sdias.c (revision 7712f83a)
1 /*
2  * Sclp "store data in absolut storage"
3  *
4  * Copyright IBM Corp. 2003,2007
5  * Author(s): Michael Holzheu
6  */
7 
8 #define KMSG_COMPONENT "sclp_sdias"
9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
10 
11 #include <linux/sched.h>
12 #include <asm/sclp.h>
13 #include <asm/debug.h>
14 #include <asm/ipl.h>
15 
16 #include "sclp.h"
17 #include "sclp_rw.h"
18 
19 #define TRACE(x...) debug_sprintf_event(sdias_dbf, 1, x)
20 
21 #define SDIAS_RETRIES 300
22 #define SDIAS_SLEEP_TICKS 50
23 
24 #define EQ_STORE_DATA	0x0
25 #define EQ_SIZE		0x1
26 #define DI_FCP_DUMP	0x0
27 #define ASA_SIZE_32	0x0
28 #define ASA_SIZE_64	0x1
29 #define EVSTATE_ALL_STORED	0x0
30 #define EVSTATE_NO_DATA		0x3
31 #define EVSTATE_PART_STORED	0x10
32 
33 static struct debug_info *sdias_dbf;
34 
35 static struct sclp_register sclp_sdias_register = {
36 	.send_mask = EVTYP_SDIAS_MASK,
37 };
38 
39 struct sdias_evbuf {
40 	struct	evbuf_header hdr;
41 	u8	event_qual;
42 	u8	data_id;
43 	u64	reserved2;
44 	u32	event_id;
45 	u16	reserved3;
46 	u8	asa_size;
47 	u8	event_status;
48 	u32	reserved4;
49 	u32	blk_cnt;
50 	u64	asa;
51 	u32	reserved5;
52 	u32	fbn;
53 	u32	reserved6;
54 	u32	lbn;
55 	u16	reserved7;
56 	u16	dbs;
57 } __attribute__((packed));
58 
59 struct sdias_sccb {
60 	struct sccb_header  hdr;
61 	struct sdias_evbuf  evbuf;
62 } __attribute__((packed));
63 
64 static struct sdias_sccb sccb __attribute__((aligned(4096)));
65 
66 static int sclp_req_done;
67 static wait_queue_head_t sdias_wq;
68 static DEFINE_MUTEX(sdias_mutex);
69 
70 static void sdias_callback(struct sclp_req *request, void *data)
71 {
72 	sclp_req_done = 1;
73 	wake_up(&sdias_wq); /* Inform caller, that request is complete */
74 	TRACE("callback done\n");
75 }
76 
77 static int sdias_sclp_send(struct sclp_req *req)
78 {
79 	int retries;
80 	int rc;
81 
82 	for (retries = SDIAS_RETRIES; retries; retries--) {
83 		sclp_req_done = 0;
84 		TRACE("add request\n");
85 		rc = sclp_add_request(req);
86 		if (rc) {
87 			/* not initiated, wait some time and retry */
88 			set_current_state(TASK_INTERRUPTIBLE);
89 			TRACE("add request failed: rc = %i\n",rc);
90 			schedule_timeout(SDIAS_SLEEP_TICKS);
91 			continue;
92 		}
93 		/* initiated, wait for completion of service call */
94 		wait_event(sdias_wq, (sclp_req_done == 1));
95 		if (req->status == SCLP_REQ_FAILED) {
96 			TRACE("sclp request failed\n");
97 			rc = -EIO;
98 			continue;
99 		}
100 		TRACE("request done\n");
101 		break;
102 	}
103 	return rc;
104 }
105 
106 /*
107  * Get number of blocks (4K) available in the HSA
108  */
109 int sclp_sdias_blk_count(void)
110 {
111 	struct sclp_req request;
112 	int rc;
113 
114 	mutex_lock(&sdias_mutex);
115 
116 	memset(&sccb, 0, sizeof(sccb));
117 	memset(&request, 0, sizeof(request));
118 
119 	sccb.hdr.length = sizeof(sccb);
120 	sccb.evbuf.hdr.length = sizeof(struct sdias_evbuf);
121 	sccb.evbuf.hdr.type = EVTYP_SDIAS;
122 	sccb.evbuf.event_qual = EQ_SIZE;
123 	sccb.evbuf.data_id = DI_FCP_DUMP;
124 	sccb.evbuf.event_id = 4712;
125 	sccb.evbuf.dbs = 1;
126 
127 	request.sccb = &sccb;
128 	request.command = SCLP_CMDW_WRITE_EVENT_DATA;
129 	request.status = SCLP_REQ_FILLED;
130 	request.callback = sdias_callback;
131 
132 	rc = sdias_sclp_send(&request);
133 	if (rc) {
134 		pr_err("sclp_send failed for get_nr_blocks\n");
135 		goto out;
136 	}
137 	if (sccb.hdr.response_code != 0x0020) {
138 		TRACE("send failed: %x\n", sccb.hdr.response_code);
139 		rc = -EIO;
140 		goto out;
141 	}
142 
143 	switch (sccb.evbuf.event_status) {
144 		case 0:
145 			rc = sccb.evbuf.blk_cnt;
146 			break;
147 		default:
148 			pr_err("SCLP error: %x\n",
149 			       sccb.evbuf.event_status);
150 			rc = -EIO;
151 			goto out;
152 	}
153 	TRACE("%i blocks\n", rc);
154 out:
155 	mutex_unlock(&sdias_mutex);
156 	return rc;
157 }
158 
159 /*
160  * Copy from HSA to absolute storage (not reentrant):
161  *
162  * @dest     : Address of buffer where data should be copied
163  * @start_blk: Start Block (beginning with 1)
164  * @nr_blks  : Number of 4K blocks to copy
165  *
166  * Return Value: 0 : Requested 'number' of blocks of data copied
167  *		 <0: ERROR - negative event status
168  */
169 int sclp_sdias_copy(void *dest, int start_blk, int nr_blks)
170 {
171 	struct sclp_req request;
172 	int rc;
173 
174 	mutex_lock(&sdias_mutex);
175 
176 	memset(&sccb, 0, sizeof(sccb));
177 	memset(&request, 0, sizeof(request));
178 
179 	sccb.hdr.length = sizeof(sccb);
180 	sccb.evbuf.hdr.length = sizeof(struct sdias_evbuf);
181 	sccb.evbuf.hdr.type = EVTYP_SDIAS;
182 	sccb.evbuf.hdr.flags = 0;
183 	sccb.evbuf.event_qual = EQ_STORE_DATA;
184 	sccb.evbuf.data_id = DI_FCP_DUMP;
185 	sccb.evbuf.event_id = 4712;
186 #ifdef __s390x__
187 	sccb.evbuf.asa_size = ASA_SIZE_64;
188 #else
189 	sccb.evbuf.asa_size = ASA_SIZE_32;
190 #endif
191 	sccb.evbuf.event_status = 0;
192 	sccb.evbuf.blk_cnt = nr_blks;
193 	sccb.evbuf.asa = (unsigned long)dest;
194 	sccb.evbuf.fbn = start_blk;
195 	sccb.evbuf.lbn = 0;
196 	sccb.evbuf.dbs = 1;
197 
198 	request.sccb	 = &sccb;
199 	request.command  = SCLP_CMDW_WRITE_EVENT_DATA;
200 	request.status	 = SCLP_REQ_FILLED;
201 	request.callback = sdias_callback;
202 
203 	rc = sdias_sclp_send(&request);
204 	if (rc) {
205 		pr_err("sclp_send failed: %x\n", rc);
206 		goto out;
207 	}
208 	if (sccb.hdr.response_code != 0x0020) {
209 		TRACE("copy failed: %x\n", sccb.hdr.response_code);
210 		rc = -EIO;
211 		goto out;
212 	}
213 
214 	switch (sccb.evbuf.event_status) {
215 		case EVSTATE_ALL_STORED:
216 			TRACE("all stored\n");
217 		case EVSTATE_PART_STORED:
218 			TRACE("part stored: %i\n", sccb.evbuf.blk_cnt);
219 			break;
220 		case EVSTATE_NO_DATA:
221 			TRACE("no data\n");
222 		default:
223 			pr_err("Error from SCLP while copying hsa. "
224 			       "Event status = %x\n",
225 			       sccb.evbuf.event_status);
226 			rc = -EIO;
227 	}
228 out:
229 	mutex_unlock(&sdias_mutex);
230 	return rc;
231 }
232 
233 int __init sclp_sdias_init(void)
234 {
235 	int rc;
236 
237 	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
238 		return 0;
239 	sdias_dbf = debug_register("dump_sdias", 4, 1, 4 * sizeof(long));
240 	debug_register_view(sdias_dbf, &debug_sprintf_view);
241 	debug_set_level(sdias_dbf, 6);
242 	rc = sclp_register(&sclp_sdias_register);
243 	if (rc)
244 		return rc;
245 	init_waitqueue_head(&sdias_wq);
246 	TRACE("init done\n");
247 	return 0;
248 }
249 
250 void __exit sclp_sdias_exit(void)
251 {
252 	debug_unregister(sdias_dbf);
253 	sclp_unregister(&sclp_sdias_register);
254 }
255