Merge branch 'master' into for_paulus
[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         data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L);
50         cqr->cpaddr = NULL;
51         if (cplength > 0) {
52                 cqr->cpaddr = (struct ccw1 *) data;
53                 data += cplength*sizeof(struct ccw1);
54                 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
55         }
56         cqr->data = NULL;
57         if (datasize > 0) {
58                 cqr->data = data;
59                 memset(cqr->data, 0, datasize);
60         }
61         strncpy((char *) &cqr->magic, magic, 4);
62         ASCEBC((char *) &cqr->magic, 4);
63         set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
64         dasd_get_device(device);
65         return cqr;
66 }
67
68 void
69 dasd_free_erp_request(struct dasd_ccw_req * cqr, struct dasd_device * device)
70 {
71         unsigned long flags;
72
73         spin_lock_irqsave(&device->mem_lock, flags);
74         dasd_free_chunk(&device->erp_chunks, cqr);
75         spin_unlock_irqrestore(&device->mem_lock, flags);
76         atomic_dec(&device->ref_count);
77 }
78
79
80 /*
81  * dasd_default_erp_action just retries the current cqr
82  */
83 struct dasd_ccw_req *
84 dasd_default_erp_action(struct dasd_ccw_req * cqr)
85 {
86         struct dasd_device *device;
87
88         device = cqr->device;
89
90         /* just retry - there is nothing to save ... I got no sense data.... */
91         if (cqr->retries > 0) {
92                 DEV_MESSAGE (KERN_DEBUG, device,
93                              "default ERP called (%i retries left)",
94                              cqr->retries);
95                 cqr->lpm    = LPM_ANYPATH;
96                 cqr->status = DASD_CQR_QUEUED;
97         } else {
98                 DEV_MESSAGE (KERN_WARNING, device, "%s",
99                              "default ERP called (NO retry left)");
100                 cqr->status = DASD_CQR_FAILED;
101                 cqr->stopclk = get_clock ();
102         }
103         return cqr;
104 }                               /* end dasd_default_erp_action */
105
106 /*
107  * DESCRIPTION
108  *   Frees all ERPs of the current ERP Chain and set the status
109  *   of the original CQR either to DASD_CQR_DONE if ERP was successful
110  *   or to DASD_CQR_FAILED if ERP was NOT successful.
111  *   NOTE: This function is only called if no discipline postaction
112  *         is available
113  *
114  * PARAMETER
115  *   erp                current erp_head
116  *
117  * RETURN VALUES
118  *   cqr                pointer to the original CQR
119  */
120 struct dasd_ccw_req *
121 dasd_default_erp_postaction(struct dasd_ccw_req * cqr)
122 {
123         struct dasd_device *device;
124         int success;
125
126         BUG_ON(cqr->refers == NULL || cqr->function == NULL);
127
128         device = cqr->device;
129         success = cqr->status == DASD_CQR_DONE;
130
131         /* free all ERPs - but NOT the original cqr */
132         while (cqr->refers != NULL) {
133                 struct dasd_ccw_req *refers;
134
135                 refers = cqr->refers;
136                 /* remove the request from the device queue */
137                 list_del(&cqr->list);
138                 /* free the finished erp request */
139                 dasd_free_erp_request(cqr, device);
140                 cqr = refers;
141         }
142
143         /* set corresponding status to original cqr */
144         if (success)
145                 cqr->status = DASD_CQR_DONE;
146         else {
147                 cqr->status = DASD_CQR_FAILED;
148                 cqr->stopclk = get_clock();
149         }
150
151         return cqr;
152
153 }                               /* end default_erp_postaction */
154
155 void
156 dasd_log_sense(struct dasd_ccw_req *cqr, struct irb *irb)
157 {
158         struct dasd_device *device;
159
160         device = cqr->device;
161         /* dump sense data */
162         if (device->discipline && device->discipline->dump_sense)
163                 device->discipline->dump_sense(device, cqr, irb);
164 }
165
166 EXPORT_SYMBOL(dasd_default_erp_action);
167 EXPORT_SYMBOL(dasd_default_erp_postaction);
168 EXPORT_SYMBOL(dasd_alloc_erp_request);
169 EXPORT_SYMBOL(dasd_free_erp_request);
170 EXPORT_SYMBOL(dasd_log_sense);