Linux 3.4.102
[linux/fpc-iii.git] / drivers / target / iscsi / iscsi_target_erl2.c
blob1af1f21af21fd01735eab9cec3f2369246e69bd4
1 /*******************************************************************************
2 * This file contains error recovery level two functions used by
3 * the iSCSI Target driver.
5 * \u00a9 Copyright 2007-2011 RisingTide Systems LLC.
7 * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
9 * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 ******************************************************************************/
22 #include <scsi/iscsi_proto.h>
23 #include <target/target_core_base.h>
24 #include <target/target_core_fabric.h>
26 #include "iscsi_target_core.h"
27 #include "iscsi_target_datain_values.h"
28 #include "iscsi_target_util.h"
29 #include "iscsi_target_erl0.h"
30 #include "iscsi_target_erl1.h"
31 #include "iscsi_target_erl2.h"
32 #include "iscsi_target.h"
35 * FIXME: Does RData SNACK apply here as well?
37 void iscsit_create_conn_recovery_datain_values(
38 struct iscsi_cmd *cmd,
39 u32 exp_data_sn)
41 u32 data_sn = 0;
42 struct iscsi_conn *conn = cmd->conn;
44 cmd->next_burst_len = 0;
45 cmd->read_data_done = 0;
47 while (exp_data_sn > data_sn) {
48 if ((cmd->next_burst_len +
49 conn->conn_ops->MaxRecvDataSegmentLength) <
50 conn->sess->sess_ops->MaxBurstLength) {
51 cmd->read_data_done +=
52 conn->conn_ops->MaxRecvDataSegmentLength;
53 cmd->next_burst_len +=
54 conn->conn_ops->MaxRecvDataSegmentLength;
55 } else {
56 cmd->read_data_done +=
57 (conn->sess->sess_ops->MaxBurstLength -
58 cmd->next_burst_len);
59 cmd->next_burst_len = 0;
61 data_sn++;
65 void iscsit_create_conn_recovery_dataout_values(
66 struct iscsi_cmd *cmd)
68 u32 write_data_done = 0;
69 struct iscsi_conn *conn = cmd->conn;
71 cmd->data_sn = 0;
72 cmd->next_burst_len = 0;
74 while (cmd->write_data_done > write_data_done) {
75 if ((write_data_done + conn->sess->sess_ops->MaxBurstLength) <=
76 cmd->write_data_done)
77 write_data_done += conn->sess->sess_ops->MaxBurstLength;
78 else
79 break;
82 cmd->write_data_done = write_data_done;
85 static int iscsit_attach_active_connection_recovery_entry(
86 struct iscsi_session *sess,
87 struct iscsi_conn_recovery *cr)
89 spin_lock(&sess->cr_a_lock);
90 list_add_tail(&cr->cr_list, &sess->cr_active_list);
91 spin_unlock(&sess->cr_a_lock);
93 return 0;
96 static int iscsit_attach_inactive_connection_recovery_entry(
97 struct iscsi_session *sess,
98 struct iscsi_conn_recovery *cr)
100 spin_lock(&sess->cr_i_lock);
101 list_add_tail(&cr->cr_list, &sess->cr_inactive_list);
103 sess->conn_recovery_count++;
104 pr_debug("Incremented connection recovery count to %u for"
105 " SID: %u\n", sess->conn_recovery_count, sess->sid);
106 spin_unlock(&sess->cr_i_lock);
108 return 0;
111 struct iscsi_conn_recovery *iscsit_get_inactive_connection_recovery_entry(
112 struct iscsi_session *sess,
113 u16 cid)
115 struct iscsi_conn_recovery *cr;
117 spin_lock(&sess->cr_i_lock);
118 list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
119 if (cr->cid == cid) {
120 spin_unlock(&sess->cr_i_lock);
121 return cr;
124 spin_unlock(&sess->cr_i_lock);
126 return NULL;
129 void iscsit_free_connection_recovery_entires(struct iscsi_session *sess)
131 struct iscsi_cmd *cmd, *cmd_tmp;
132 struct iscsi_conn_recovery *cr, *cr_tmp;
134 spin_lock(&sess->cr_a_lock);
135 list_for_each_entry_safe(cr, cr_tmp, &sess->cr_active_list, cr_list) {
136 list_del(&cr->cr_list);
137 spin_unlock(&sess->cr_a_lock);
139 spin_lock(&cr->conn_recovery_cmd_lock);
140 list_for_each_entry_safe(cmd, cmd_tmp,
141 &cr->conn_recovery_cmd_list, i_list) {
143 list_del(&cmd->i_list);
144 cmd->conn = NULL;
145 spin_unlock(&cr->conn_recovery_cmd_lock);
146 iscsit_free_cmd(cmd);
147 spin_lock(&cr->conn_recovery_cmd_lock);
149 spin_unlock(&cr->conn_recovery_cmd_lock);
150 spin_lock(&sess->cr_a_lock);
152 kfree(cr);
154 spin_unlock(&sess->cr_a_lock);
156 spin_lock(&sess->cr_i_lock);
157 list_for_each_entry_safe(cr, cr_tmp, &sess->cr_inactive_list, cr_list) {
158 list_del(&cr->cr_list);
159 spin_unlock(&sess->cr_i_lock);
161 spin_lock(&cr->conn_recovery_cmd_lock);
162 list_for_each_entry_safe(cmd, cmd_tmp,
163 &cr->conn_recovery_cmd_list, i_list) {
165 list_del(&cmd->i_list);
166 cmd->conn = NULL;
167 spin_unlock(&cr->conn_recovery_cmd_lock);
168 iscsit_free_cmd(cmd);
169 spin_lock(&cr->conn_recovery_cmd_lock);
171 spin_unlock(&cr->conn_recovery_cmd_lock);
172 spin_lock(&sess->cr_i_lock);
174 kfree(cr);
176 spin_unlock(&sess->cr_i_lock);
179 int iscsit_remove_active_connection_recovery_entry(
180 struct iscsi_conn_recovery *cr,
181 struct iscsi_session *sess)
183 spin_lock(&sess->cr_a_lock);
184 list_del(&cr->cr_list);
186 sess->conn_recovery_count--;
187 pr_debug("Decremented connection recovery count to %u for"
188 " SID: %u\n", sess->conn_recovery_count, sess->sid);
189 spin_unlock(&sess->cr_a_lock);
191 kfree(cr);
193 return 0;
196 int iscsit_remove_inactive_connection_recovery_entry(
197 struct iscsi_conn_recovery *cr,
198 struct iscsi_session *sess)
200 spin_lock(&sess->cr_i_lock);
201 list_del(&cr->cr_list);
202 spin_unlock(&sess->cr_i_lock);
204 return 0;
208 * Called with cr->conn_recovery_cmd_lock help.
210 int iscsit_remove_cmd_from_connection_recovery(
211 struct iscsi_cmd *cmd,
212 struct iscsi_session *sess)
214 struct iscsi_conn_recovery *cr;
216 if (!cmd->cr) {
217 pr_err("struct iscsi_conn_recovery pointer for ITT: 0x%08x"
218 " is NULL!\n", cmd->init_task_tag);
219 BUG();
221 cr = cmd->cr;
223 list_del(&cmd->i_list);
224 return --cr->cmd_count;
227 void iscsit_discard_cr_cmds_by_expstatsn(
228 struct iscsi_conn_recovery *cr,
229 u32 exp_statsn)
231 u32 dropped_count = 0;
232 struct iscsi_cmd *cmd, *cmd_tmp;
233 struct iscsi_session *sess = cr->sess;
235 spin_lock(&cr->conn_recovery_cmd_lock);
236 list_for_each_entry_safe(cmd, cmd_tmp,
237 &cr->conn_recovery_cmd_list, i_list) {
239 if (((cmd->deferred_i_state != ISTATE_SENT_STATUS) &&
240 (cmd->deferred_i_state != ISTATE_REMOVE)) ||
241 (cmd->stat_sn >= exp_statsn)) {
242 continue;
245 dropped_count++;
246 pr_debug("Dropping Acknowledged ITT: 0x%08x, StatSN:"
247 " 0x%08x, CID: %hu.\n", cmd->init_task_tag,
248 cmd->stat_sn, cr->cid);
250 iscsit_remove_cmd_from_connection_recovery(cmd, sess);
252 spin_unlock(&cr->conn_recovery_cmd_lock);
253 iscsit_free_cmd(cmd);
254 spin_lock(&cr->conn_recovery_cmd_lock);
256 spin_unlock(&cr->conn_recovery_cmd_lock);
258 pr_debug("Dropped %u total acknowledged commands on"
259 " CID: %hu less than old ExpStatSN: 0x%08x\n",
260 dropped_count, cr->cid, exp_statsn);
262 if (!cr->cmd_count) {
263 pr_debug("No commands to be reassigned for failed"
264 " connection CID: %hu on SID: %u\n",
265 cr->cid, sess->sid);
266 iscsit_remove_inactive_connection_recovery_entry(cr, sess);
267 iscsit_attach_active_connection_recovery_entry(sess, cr);
268 pr_debug("iSCSI connection recovery successful for CID:"
269 " %hu on SID: %u\n", cr->cid, sess->sid);
270 iscsit_remove_active_connection_recovery_entry(cr, sess);
271 } else {
272 iscsit_remove_inactive_connection_recovery_entry(cr, sess);
273 iscsit_attach_active_connection_recovery_entry(sess, cr);
277 int iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(struct iscsi_conn *conn)
279 u32 dropped_count = 0;
280 struct iscsi_cmd *cmd, *cmd_tmp;
281 struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
282 struct iscsi_session *sess = conn->sess;
284 mutex_lock(&sess->cmdsn_mutex);
285 list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp,
286 &sess->sess_ooo_cmdsn_list, ooo_list) {
288 if (ooo_cmdsn->cid != conn->cid)
289 continue;
291 dropped_count++;
292 pr_debug("Dropping unacknowledged CmdSN:"
293 " 0x%08x during connection recovery on CID: %hu\n",
294 ooo_cmdsn->cmdsn, conn->cid);
295 iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
297 mutex_unlock(&sess->cmdsn_mutex);
299 spin_lock_bh(&conn->cmd_lock);
300 list_for_each_entry_safe(cmd, cmd_tmp, &conn->conn_cmd_list, i_list) {
301 if (!(cmd->cmd_flags & ICF_OOO_CMDSN))
302 continue;
304 list_del(&cmd->i_list);
306 spin_unlock_bh(&conn->cmd_lock);
307 iscsit_free_cmd(cmd);
308 spin_lock_bh(&conn->cmd_lock);
310 spin_unlock_bh(&conn->cmd_lock);
312 pr_debug("Dropped %u total unacknowledged commands on CID:"
313 " %hu for ExpCmdSN: 0x%08x.\n", dropped_count, conn->cid,
314 sess->exp_cmd_sn);
315 return 0;
318 int iscsit_prepare_cmds_for_realligance(struct iscsi_conn *conn)
320 u32 cmd_count = 0;
321 struct iscsi_cmd *cmd, *cmd_tmp;
322 struct iscsi_conn_recovery *cr;
325 * Allocate an struct iscsi_conn_recovery for this connection.
326 * Each struct iscsi_cmd contains an struct iscsi_conn_recovery pointer
327 * (struct iscsi_cmd->cr) so we need to allocate this before preparing the
328 * connection's command list for connection recovery.
330 cr = kzalloc(sizeof(struct iscsi_conn_recovery), GFP_KERNEL);
331 if (!cr) {
332 pr_err("Unable to allocate memory for"
333 " struct iscsi_conn_recovery.\n");
334 return -1;
336 INIT_LIST_HEAD(&cr->cr_list);
337 INIT_LIST_HEAD(&cr->conn_recovery_cmd_list);
338 spin_lock_init(&cr->conn_recovery_cmd_lock);
340 * Only perform connection recovery on ISCSI_OP_SCSI_CMD or
341 * ISCSI_OP_NOOP_OUT opcodes. For all other opcodes call
342 * list_del(&cmd->i_list); to release the command to the
343 * session pool and remove it from the connection's list.
345 * Also stop the DataOUT timer, which will be restarted after
346 * sending the TMR response.
348 spin_lock_bh(&conn->cmd_lock);
349 list_for_each_entry_safe(cmd, cmd_tmp, &conn->conn_cmd_list, i_list) {
351 if ((cmd->iscsi_opcode != ISCSI_OP_SCSI_CMD) &&
352 (cmd->iscsi_opcode != ISCSI_OP_NOOP_OUT)) {
353 pr_debug("Not performing realligence on"
354 " Opcode: 0x%02x, ITT: 0x%08x, CmdSN: 0x%08x,"
355 " CID: %hu\n", cmd->iscsi_opcode,
356 cmd->init_task_tag, cmd->cmd_sn, conn->cid);
358 list_del(&cmd->i_list);
359 spin_unlock_bh(&conn->cmd_lock);
360 iscsit_free_cmd(cmd);
361 spin_lock_bh(&conn->cmd_lock);
362 continue;
366 * Special case where commands greater than or equal to
367 * the session's ExpCmdSN are attached to the connection
368 * list but not to the out of order CmdSN list. The one
369 * obvious case is when a command with immediate data
370 * attached must only check the CmdSN against ExpCmdSN
371 * after the data is received. The special case below
372 * is when the connection fails before data is received,
373 * but also may apply to other PDUs, so it has been
374 * made generic here.
376 if (!(cmd->cmd_flags & ICF_OOO_CMDSN) && !cmd->immediate_cmd &&
377 (cmd->cmd_sn >= conn->sess->exp_cmd_sn)) {
378 list_del(&cmd->i_list);
379 spin_unlock_bh(&conn->cmd_lock);
380 iscsit_free_cmd(cmd);
381 spin_lock_bh(&conn->cmd_lock);
382 continue;
385 cmd_count++;
386 pr_debug("Preparing Opcode: 0x%02x, ITT: 0x%08x,"
387 " CmdSN: 0x%08x, StatSN: 0x%08x, CID: %hu for"
388 " realligence.\n", cmd->iscsi_opcode,
389 cmd->init_task_tag, cmd->cmd_sn, cmd->stat_sn,
390 conn->cid);
392 cmd->deferred_i_state = cmd->i_state;
393 cmd->i_state = ISTATE_IN_CONNECTION_RECOVERY;
395 if (cmd->data_direction == DMA_TO_DEVICE)
396 iscsit_stop_dataout_timer(cmd);
398 cmd->sess = conn->sess;
400 list_del(&cmd->i_list);
401 spin_unlock_bh(&conn->cmd_lock);
403 iscsit_free_all_datain_reqs(cmd);
405 transport_wait_for_tasks(&cmd->se_cmd);
407 * Add the struct iscsi_cmd to the connection recovery cmd list
409 spin_lock(&cr->conn_recovery_cmd_lock);
410 list_add_tail(&cmd->i_list, &cr->conn_recovery_cmd_list);
411 spin_unlock(&cr->conn_recovery_cmd_lock);
413 spin_lock_bh(&conn->cmd_lock);
414 cmd->cr = cr;
415 cmd->conn = NULL;
417 spin_unlock_bh(&conn->cmd_lock);
419 * Fill in the various values in the preallocated struct iscsi_conn_recovery.
421 cr->cid = conn->cid;
422 cr->cmd_count = cmd_count;
423 cr->maxrecvdatasegmentlength = conn->conn_ops->MaxRecvDataSegmentLength;
424 cr->sess = conn->sess;
426 iscsit_attach_inactive_connection_recovery_entry(conn->sess, cr);
428 return 0;
431 int iscsit_connection_recovery_transport_reset(struct iscsi_conn *conn)
433 atomic_set(&conn->connection_recovery, 1);
435 if (iscsit_close_connection(conn) < 0)
436 return -1;
438 return 0;