[S390] dasd: add hyper PAV support to DASD device driver, part 1
[safe/jmp/linux-2.6] / drivers / s390 / block / dasd_erp.c
1 /*
2  * File...........: linux/drivers/s390/block/dasd.c
3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
4  *                  Horst Hummel <Horst.Hummel@de.ibm.com>
5  *                  Carsten Otte <Cotte@de.ibm.com>
6  *                  Martin Schwidefsky <schwidefsky@de.ibm.com>
7  * Bugreports.to..: <Linux390@de.ibm.com>
8  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
9  *
10  */
11
12 #include <linux/ctype.h>
13 #include <linux/init.h>
14
15 #include <asm/debug.h>
16 #include <asm/ebcdic.h>
17 #include <asm/uaccess.h>
18
19 /* This is ugly... */
20 #define PRINTK_HEADER "dasd_erp:"
21
22 #include "dasd_int.h"
23
24 struct dasd_ccw_req *
25 dasd_alloc_erp_request(char *magic, int cplength, int datasize,
26                        struct dasd_device * device)
27 {
28         unsigned long flags;
29         struct dasd_ccw_req *cqr;
30         char *data;
31         int size;
32
33         /* Sanity checks */
34         BUG_ON( magic == NULL || datasize > PAGE_SIZE ||
35              (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
36
37         size = (sizeof(struct dasd_ccw_req) + 7L) & -8L;
38         if (cplength > 0)
39                 size += cplength * sizeof(struct ccw1);
40         if (datasize > 0)
41                 size += datasize;
42         spin_lock_irqsave(&device->mem_lock, flags);
43         cqr = (struct dasd_ccw_req *)
44                 dasd_alloc_chunk(&device->erp_chunks, size);
45         spin_unlock_irqrestore(&device->mem_lock, flags);
46         if (cqr == NULL)
47                 return ERR_PTR(-ENOMEM);
48         memset(cqr, 0, sizeof(struct dasd_ccw_req));
49         INIT_LIST_HEAD(&cqr->devlist);
50         INIT_LIST_HEAD(&cqr->blocklist);
51         data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L);
52         cqr->cpaddr = NULL;
53         if (cplength > 0) {
54                 cqr->cpaddr = (struct ccw1 *) data;
55                 data += cplength*sizeof(struct ccw1);
56                 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
57         }
58         cqr->data = NULL;
59         if (datasize > 0) {
60                 cqr->data = data;
61                 memset(cqr->data, 0, datasize);
62         }
63         strncpy((char *) &cqr->magic, magic, 4);
64         ASCEBC((char *) &cqr->magic, 4);
65         set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
66         dasd_get_device(device);
67         return cqr;
68 }
69
70 void
71 dasd_free_erp_request(struct dasd_ccw_req *cqr, struct dasd_device * device)
72 {
73         unsigned long flags;
74
75         spin_lock_irqsave(&device->mem_lock, flags);
76         dasd_free_chunk(&device->erp_chunks, cqr);
77         spin_unlock_irqrestore(&device->mem_lock, flags);
78         atomic_dec(&device->ref_count);
79 }
80
81
82 /*
83  * dasd_default_erp_action just retries the current cqr
84  */
85 struct dasd_ccw_req *
86 dasd_default_erp_action(struct dasd_ccw_req *cqr)
87 {
88         struct dasd_device *device;
89
90         device = cqr->startdev;
91
92         /* just retry - there is nothing to save ... I got no sense data.... */
93         if (cqr->retries > 0) {
94                 DEV_MESSAGE (KERN_DEBUG, device,
95                              "default ERP called (%i retries left)",
96                              cqr->retries);
97                 cqr->lpm    = LPM_ANYPATH;
98                 cqr->status = DASD_CQR_FILLED;
99         } else {
100                 DEV_MESSAGE (KERN_WARNING, device, "%s",
101                              "default ERP called (NO retry left)");
102                 cqr->status = DASD_CQR_FAILED;
103                 cqr->stopclk = get_clock();
104         }
105         return cqr;
106 }                               /* end dasd_default_erp_action */
107
108 /*
109  * DESCRIPTION
110  *   Frees all ERPs of the current ERP Chain and set the status
111  *   of the original CQR either to DASD_CQR_DONE if ERP was successful
112  *   or to DASD_CQR_FAILED if ERP was NOT successful.
113  *   NOTE: This function is only called if no discipline postaction
114  *         is available
115  *
116  * PARAMETER
117  *   erp                current erp_head
118  *
119  * RETURN VALUES
120  *   cqr                pointer to the original CQR
121  */
122 struct dasd_ccw_req *dasd_default_erp_postaction(struct dasd_ccw_req *cqr)
123 {
124         int success;
125
126         BUG_ON(cqr->refers == NULL || cqr->function == NULL);
127
128         success = cqr->status == DASD_CQR_DONE;
129
130         /* free all ERPs - but NOT the original cqr */
131         while (cqr->refers != NULL) {
132                 struct dasd_ccw_req *refers;
133
134                 refers = cqr->refers;
135                 /* remove the request from the block queue */
136                 list_del(&cqr->blocklist);
137                 /* free the finished erp request */
138                 dasd_free_erp_request(cqr, cqr->memdev);
139                 cqr = refers;
140         }
141
142         /* set corresponding status to original cqr */
143         if (success)
144                 cqr->status = DASD_CQR_DONE;
145         else {
146                 cqr->status = DASD_CQR_FAILED;
147                 cqr->stopclk = get_clock();
148         }
149
150         return cqr;
151
152 }                               /* end default_erp_postaction */
153
154 void
155 dasd_log_sense(struct dasd_ccw_req *cqr, struct irb *irb)
156 {
157         struct dasd_device *device;
158
159         device = cqr->startdev;
160         /* dump sense data */
161         if (device->discipline && device->discipline->dump_sense)
162                 device->discipline->dump_sense(device, cqr, irb);
163 }
164
165 EXPORT_SYMBOL(dasd_default_erp_action);
166 EXPORT_SYMBOL(dasd_default_erp_postaction);
167 EXPORT_SYMBOL(dasd_alloc_erp_request);
168 EXPORT_SYMBOL(dasd_free_erp_request);
169 EXPORT_SYMBOL(dasd_log_sense);