Make sure the value in abs() does not get truncated if it is greater than 2^32
[linux-2.6/linux-2.6-openrd.git] / drivers / s390 / char / sclp_sdias.c
blob6a1c58dc61a78e920c4e626ab61b04f1747c3418
1 /*
2 * Sclp "store data in absolut storage"
4 * Copyright IBM Corp. 2003,2007
5 * Author(s): Michael Holzheu
6 */
8 #define KMSG_COMPONENT "sclp_sdias"
9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11 #include <linux/sched.h>
12 #include <asm/sclp.h>
13 #include <asm/debug.h>
14 #include <asm/ipl.h>
16 #include "sclp.h"
17 #include "sclp_rw.h"
19 #define TRACE(x...) debug_sprintf_event(sdias_dbf, 1, x)
21 #define SDIAS_RETRIES 300
22 #define SDIAS_SLEEP_TICKS 50
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
33 static struct debug_info *sdias_dbf;
35 static struct sclp_register sclp_sdias_register = {
36 .send_mask = EVTYP_SDIAS_MASK,
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));
59 struct sdias_sccb {
60 struct sccb_header hdr;
61 struct sdias_evbuf evbuf;
62 } __attribute__((packed));
64 static struct sdias_sccb sccb __attribute__((aligned(4096)));
66 static int sclp_req_done;
67 static wait_queue_head_t sdias_wq;
68 static DEFINE_MUTEX(sdias_mutex);
70 static void sdias_callback(struct sclp_req *request, void *data)
72 struct sdias_sccb *cbsccb;
74 cbsccb = (struct sdias_sccb *) request->sccb;
75 sclp_req_done = 1;
76 wake_up(&sdias_wq); /* Inform caller, that request is complete */
77 TRACE("callback done\n");
80 static int sdias_sclp_send(struct sclp_req *req)
82 int retries;
83 int rc;
85 for (retries = SDIAS_RETRIES; retries; retries--) {
86 sclp_req_done = 0;
87 TRACE("add request\n");
88 rc = sclp_add_request(req);
89 if (rc) {
90 /* not initiated, wait some time and retry */
91 set_current_state(TASK_INTERRUPTIBLE);
92 TRACE("add request failed: rc = %i\n",rc);
93 schedule_timeout(SDIAS_SLEEP_TICKS);
94 continue;
96 /* initiated, wait for completion of service call */
97 wait_event(sdias_wq, (sclp_req_done == 1));
98 if (req->status == SCLP_REQ_FAILED) {
99 TRACE("sclp request failed\n");
100 rc = -EIO;
101 continue;
103 TRACE("request done\n");
104 break;
106 return rc;
110 * Get number of blocks (4K) available in the HSA
112 int sclp_sdias_blk_count(void)
114 struct sclp_req request;
115 int rc;
117 mutex_lock(&sdias_mutex);
119 memset(&sccb, 0, sizeof(sccb));
120 memset(&request, 0, sizeof(request));
122 sccb.hdr.length = sizeof(sccb);
123 sccb.evbuf.hdr.length = sizeof(struct sdias_evbuf);
124 sccb.evbuf.hdr.type = EVTYP_SDIAS;
125 sccb.evbuf.event_qual = EQ_SIZE;
126 sccb.evbuf.data_id = DI_FCP_DUMP;
127 sccb.evbuf.event_id = 4712;
128 sccb.evbuf.dbs = 1;
130 request.sccb = &sccb;
131 request.command = SCLP_CMDW_WRITE_EVENT_DATA;
132 request.status = SCLP_REQ_FILLED;
133 request.callback = sdias_callback;
135 rc = sdias_sclp_send(&request);
136 if (rc) {
137 pr_err("sclp_send failed for get_nr_blocks\n");
138 goto out;
140 if (sccb.hdr.response_code != 0x0020) {
141 TRACE("send failed: %x\n", sccb.hdr.response_code);
142 rc = -EIO;
143 goto out;
146 switch (sccb.evbuf.event_status) {
147 case 0:
148 rc = sccb.evbuf.blk_cnt;
149 break;
150 default:
151 pr_err("SCLP error: %x\n",
152 sccb.evbuf.event_status);
153 rc = -EIO;
154 goto out;
156 TRACE("%i blocks\n", rc);
157 out:
158 mutex_unlock(&sdias_mutex);
159 return rc;
163 * Copy from HSA to absolute storage (not reentrant):
165 * @dest : Address of buffer where data should be copied
166 * @start_blk: Start Block (beginning with 1)
167 * @nr_blks : Number of 4K blocks to copy
169 * Return Value: 0 : Requested 'number' of blocks of data copied
170 * <0: ERROR - negative event status
172 int sclp_sdias_copy(void *dest, int start_blk, int nr_blks)
174 struct sclp_req request;
175 int rc;
177 mutex_lock(&sdias_mutex);
179 memset(&sccb, 0, sizeof(sccb));
180 memset(&request, 0, sizeof(request));
182 sccb.hdr.length = sizeof(sccb);
183 sccb.evbuf.hdr.length = sizeof(struct sdias_evbuf);
184 sccb.evbuf.hdr.type = EVTYP_SDIAS;
185 sccb.evbuf.hdr.flags = 0;
186 sccb.evbuf.event_qual = EQ_STORE_DATA;
187 sccb.evbuf.data_id = DI_FCP_DUMP;
188 sccb.evbuf.event_id = 4712;
189 #ifdef __s390x__
190 sccb.evbuf.asa_size = ASA_SIZE_64;
191 #else
192 sccb.evbuf.asa_size = ASA_SIZE_32;
193 #endif
194 sccb.evbuf.event_status = 0;
195 sccb.evbuf.blk_cnt = nr_blks;
196 sccb.evbuf.asa = (unsigned long)dest;
197 sccb.evbuf.fbn = start_blk;
198 sccb.evbuf.lbn = 0;
199 sccb.evbuf.dbs = 1;
201 request.sccb = &sccb;
202 request.command = SCLP_CMDW_WRITE_EVENT_DATA;
203 request.status = SCLP_REQ_FILLED;
204 request.callback = sdias_callback;
206 rc = sdias_sclp_send(&request);
207 if (rc) {
208 pr_err("sclp_send failed: %x\n", rc);
209 goto out;
211 if (sccb.hdr.response_code != 0x0020) {
212 TRACE("copy failed: %x\n", sccb.hdr.response_code);
213 rc = -EIO;
214 goto out;
217 switch (sccb.evbuf.event_status) {
218 case EVSTATE_ALL_STORED:
219 TRACE("all stored\n");
220 case EVSTATE_PART_STORED:
221 TRACE("part stored: %i\n", sccb.evbuf.blk_cnt);
222 break;
223 case EVSTATE_NO_DATA:
224 TRACE("no data\n");
225 default:
226 pr_err("Error from SCLP while copying hsa. "
227 "Event status = %x\n",
228 sccb.evbuf.event_status);
229 rc = -EIO;
231 out:
232 mutex_unlock(&sdias_mutex);
233 return rc;
236 int __init sclp_sdias_init(void)
238 int rc;
240 if (ipl_info.type != IPL_TYPE_FCP_DUMP)
241 return 0;
242 sdias_dbf = debug_register("dump_sdias", 4, 1, 4 * sizeof(long));
243 debug_register_view(sdias_dbf, &debug_sprintf_view);
244 debug_set_level(sdias_dbf, 6);
245 rc = sclp_register(&sclp_sdias_register);
246 if (rc)
247 return rc;
248 init_waitqueue_head(&sdias_wq);
249 TRACE("init done\n");
250 return 0;
253 void __exit sclp_sdias_exit(void)
255 debug_unregister(sdias_dbf);
256 sclp_unregister(&sclp_sdias_register);