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-rw-r--r--drivers/md/dm-mpath-hp-sw.c247
1 files changed, 0 insertions, 247 deletions
diff --git a/drivers/md/dm-mpath-hp-sw.c b/drivers/md/dm-mpath-hp-sw.c
deleted file mode 100644
index b63a0ab37c53..000000000000
--- a/drivers/md/dm-mpath-hp-sw.c
+++ /dev/null
@@ -1,247 +0,0 @@
1/*
2 * Copyright (C) 2005 Mike Christie, All rights reserved.
3 * Copyright (C) 2007 Red Hat, Inc. All rights reserved.
4 * Authors: Mike Christie
5 * Dave Wysochanski
6 *
7 * This file is released under the GPL.
8 *
9 * This module implements the specific path activation code for
10 * HP StorageWorks and FSC FibreCat Asymmetric (Active/Passive)
11 * storage arrays.
12 * These storage arrays have controller-based failover, not
13 * LUN-based failover. However, LUN-based failover is the design
14 * of dm-multipath. Thus, this module is written for LUN-based failover.
15 */
16#include <linux/blkdev.h>
17#include <linux/list.h>
18#include <linux/types.h>
19#include <scsi/scsi.h>
20#include <scsi/scsi_cmnd.h>
21#include <scsi/scsi_dbg.h>
22
23#include "dm.h"
24#include "dm-hw-handler.h"
25
26#define DM_MSG_PREFIX "multipath hp-sw"
27#define DM_HP_HWH_NAME "hp-sw"
28#define DM_HP_HWH_VER "1.0.0"
29
30struct hp_sw_context {
31 unsigned char sense[SCSI_SENSE_BUFFERSIZE];
32};
33
34/*
35 * hp_sw_error_is_retryable - Is an HP-specific check condition retryable?
36 * @req: path activation request
37 *
38 * Examine error codes of request and determine whether the error is retryable.
39 * Some error codes are already retried by scsi-ml (see
40 * scsi_decide_disposition), but some HP specific codes are not.
41 * The intent of this routine is to supply the logic for the HP specific
42 * check conditions.
43 *
44 * Returns:
45 * 1 - command completed with retryable error
46 * 0 - command completed with non-retryable error
47 *
48 * Possible optimizations
49 * 1. More hardware-specific error codes
50 */
51static int hp_sw_error_is_retryable(struct request *req)
52{
53 /*
54 * NOT_READY is known to be retryable
55 * For now we just dump out the sense data and call it retryable
56 */
57 if (status_byte(req->errors) == CHECK_CONDITION)
58 __scsi_print_sense(DM_HP_HWH_NAME, req->sense, req->sense_len);
59
60 /*
61 * At this point we don't have complete information about all the error
62 * codes from this hardware, so we are just conservative and retry
63 * when in doubt.
64 */
65 return 1;
66}
67
68/*
69 * hp_sw_end_io - Completion handler for HP path activation.
70 * @req: path activation request
71 * @error: scsi-ml error
72 *
73 * Check sense data, free request structure, and notify dm that
74 * pg initialization has completed.
75 *
76 * Context: scsi-ml softirq
77 *
78 */
79static void hp_sw_end_io(struct request *req, int error)
80{
81 struct dm_path *path = req->end_io_data;
82 unsigned err_flags = 0;
83
84 if (!error) {
85 DMDEBUG("%s path activation command - success",
86 path->dev->name);
87 goto out;
88 }
89
90 if (hp_sw_error_is_retryable(req)) {
91 DMDEBUG("%s path activation command - retry",
92 path->dev->name);
93 err_flags = MP_RETRY;
94 goto out;
95 }
96
97 DMWARN("%s path activation fail - error=0x%x",
98 path->dev->name, error);
99 err_flags = MP_FAIL_PATH;
100
101out:
102 req->end_io_data = NULL;
103 __blk_put_request(req->q, req);
104 dm_pg_init_complete(path, err_flags);
105}
106
107/*
108 * hp_sw_get_request - Allocate an HP specific path activation request
109 * @path: path on which request will be sent (needed for request queue)
110 *
111 * The START command is used for path activation request.
112 * These arrays are controller-based failover, not LUN based.
113 * One START command issued to a single path will fail over all
114 * LUNs for the same controller.
115 *
116 * Possible optimizations
117 * 1. Make timeout configurable
118 * 2. Preallocate request
119 */
120static struct request *hp_sw_get_request(struct dm_path *path)
121{
122 struct request *req;
123 struct block_device *bdev = path->dev->bdev;
124 struct request_queue *q = bdev_get_queue(bdev);
125 struct hp_sw_context *h = path->hwhcontext;
126
127 req = blk_get_request(q, WRITE, GFP_NOIO);
128 if (!req)
129 goto out;
130
131 req->timeout = 60 * HZ;
132
133 req->errors = 0;
134 req->cmd_type = REQ_TYPE_BLOCK_PC;
135 req->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE;
136 req->end_io_data = path;
137 req->sense = h->sense;
138 memset(req->sense, 0, SCSI_SENSE_BUFFERSIZE);
139
140 req->cmd[0] = START_STOP;
141 req->cmd[4] = 1;
142 req->cmd_len = COMMAND_SIZE(req->cmd[0]);
143
144out:
145 return req;
146}
147
148/*
149 * hp_sw_pg_init - HP path activation implementation.
150 * @hwh: hardware handler specific data
151 * @bypassed: unused; is the path group bypassed? (see dm-mpath.c)
152 * @path: path to send initialization command
153 *
154 * Send an HP-specific path activation command on 'path'.
155 * Do not try to optimize in any way, just send the activation command.
156 * More than one path activation command may be sent to the same controller.
157 * This seems to work fine for basic failover support.
158 *
159 * Possible optimizations
160 * 1. Detect an in-progress activation request and avoid submitting another one
161 * 2. Model the controller and only send a single activation request at a time
162 * 3. Determine the state of a path before sending an activation request
163 *
164 * Context: kmpathd (see process_queued_ios() in dm-mpath.c)
165 */
166static void hp_sw_pg_init(struct hw_handler *hwh, unsigned bypassed,
167 struct dm_path *path)
168{
169 struct request *req;
170 struct hp_sw_context *h;
171
172 path->hwhcontext = hwh->context;
173 h = hwh->context;
174
175 req = hp_sw_get_request(path);
176 if (!req) {
177 DMERR("%s path activation command - allocation fail",
178 path->dev->name);
179 goto retry;
180 }
181
182 DMDEBUG("%s path activation command - sent", path->dev->name);
183
184 blk_execute_rq_nowait(req->q, NULL, req, 1, hp_sw_end_io);
185 return;
186
187retry:
188 dm_pg_init_complete(path, MP_RETRY);
189}
190
191static int hp_sw_create(struct hw_handler *hwh, unsigned argc, char **argv)
192{
193 struct hp_sw_context *h;
194
195 h = kmalloc(sizeof(*h), GFP_KERNEL);
196 if (!h)
197 return -ENOMEM;
198
199 hwh->context = h;
200
201 return 0;
202}
203
204static void hp_sw_destroy(struct hw_handler *hwh)
205{
206 struct hp_sw_context *h = hwh->context;
207
208 kfree(h);
209}
210
211static struct hw_handler_type hp_sw_hwh = {
212 .name = DM_HP_HWH_NAME,
213 .module = THIS_MODULE,
214 .create = hp_sw_create,
215 .destroy = hp_sw_destroy,
216 .pg_init = hp_sw_pg_init,
217};
218
219static int __init hp_sw_init(void)
220{
221 int r;
222
223 r = dm_register_hw_handler(&hp_sw_hwh);
224 if (r < 0)
225 DMERR("register failed %d", r);
226 else
227 DMINFO("version " DM_HP_HWH_VER " loaded");
228
229 return r;
230}
231
232static void __exit hp_sw_exit(void)
233{
234 int r;
235
236 r = dm_unregister_hw_handler(&hp_sw_hwh);
237 if (r < 0)
238 DMERR("unregister failed %d", r);
239}
240
241module_init(hp_sw_init);
242module_exit(hp_sw_exit);
243
244MODULE_DESCRIPTION("DM Multipath HP StorageWorks / FSC FibreCat (A/P) support");
245MODULE_AUTHOR("Mike Christie, Dave Wysochanski <dm-devel@redhat.com>");
246MODULE_LICENSE("GPL");
247MODULE_VERSION(DM_HP_HWH_VER);
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-20 00:59:40 -0500