[SCSI] iscsi lib: have lib create work queue for transmitting IO
[linux-2.6-block.git] / include / scsi / libiscsi.h
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1/*
2 * iSCSI lib definitions
3 *
4 * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
5 * Copyright (C) 2004 - 2006 Mike Christie
6 * Copyright (C) 2004 - 2005 Dmitry Yusupov
7 * Copyright (C) 2004 - 2005 Alex Aizman
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
22 */
23#ifndef LIBISCSI_H
24#define LIBISCSI_H
25
26#include <linux/types.h>
40753caa 27#include <linux/wait.h>
7996a778 28#include <linux/mutex.h>
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29#include <linux/timer.h>
30#include <linux/workqueue.h>
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31#include <scsi/iscsi_proto.h>
32#include <scsi/iscsi_if.h>
262ef636 33#include <scsi/scsi_transport_iscsi.h>
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34
35struct scsi_transport_template;
a4804cd6 36struct scsi_host_template;
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37struct scsi_device;
38struct Scsi_Host;
39struct scsi_cmnd;
40struct socket;
41struct iscsi_transport;
42struct iscsi_cls_session;
43struct iscsi_cls_conn;
44struct iscsi_session;
45struct iscsi_nopin;
a4804cd6 46struct device;
7996a778 47
1548271e 48#define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
3cf7b233 49#define ISCSI_MGMT_CMDS_MAX 15
7996a778 50
e28f3d5b 51#define ISCSI_DEF_CMD_PER_LUN 32
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52
53/* Task Mgmt states */
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54enum {
55 TMF_INITIAL,
56 TMF_QUEUED,
57 TMF_SUCCESS,
58 TMF_FAILED,
59 TMF_TIMEDOUT,
60 TMF_NOT_FOUND,
61};
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62
63/* Connection suspend "bit" */
64#define ISCSI_SUSPEND_BIT 1
65
262ef636 66#define ISCSI_ITT_MASK 0x1fff
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67#define ISCSI_TOTAL_CMDS_MAX 4096
68/* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
69#define ISCSI_TOTAL_CMDS_MIN 16
7996a778 70#define ISCSI_AGE_SHIFT 28
262ef636 71#define ISCSI_AGE_MASK 0xf
7996a778 72
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73#define ISCSI_ADDRESS_BUF_LEN 64
74
da32dd68 75enum {
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76 /* this is the maximum possible storage for AHSs */
77 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
78 sizeof(struct iscsi_rlength_ahdr),
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79 ISCSI_DIGEST_SIZE = sizeof(__u32),
80};
81
7996a778 82
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83enum {
84 ISCSI_TASK_COMPLETED,
85 ISCSI_TASK_PENDING,
86 ISCSI_TASK_RUNNING,
87};
88
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89struct iscsi_r2t_info {
90 __be32 ttt; /* copied from R2T */
91 __be32 exp_statsn; /* copied from R2T */
92 uint32_t data_length; /* copied from R2T */
93 uint32_t data_offset; /* copied from R2T */
94 int data_count; /* DATA-Out payload progress */
95 int datasn;
96 /* LLDs should set/update these values */
97 int sent; /* R2T sequence progress */
98};
99
9c19a7d0 100struct iscsi_task {
7996a778 101 /*
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102 * Because LLDs allocate their hdr differently, this is a pointer
103 * and length to that storage. It must be setup at session
104 * creation time.
7996a778 105 */
577577da 106 struct iscsi_hdr *hdr;
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107 unsigned short hdr_max;
108 unsigned short hdr_len; /* accumulated size of hdr used */
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109 /* copied values in case we need to send tmfs */
110 itt_t hdr_itt;
111 __be32 cmdsn;
112 uint8_t lun[8];
113
7996a778 114 int itt; /* this ITT */
7996a778 115
857ae0bd 116 unsigned imm_count; /* imm-data (bytes) */
ffd0436e 117 /* offset in unsolicited stream (bytes); */
577577da 118 struct iscsi_r2t_info unsol_r2t;
3e5c28ad 119 char *data; /* mgmt payload */
577577da 120 unsigned data_count;
7996a778 121 struct scsi_cmnd *sc; /* associated SCSI cmd*/
7996a778 122 struct iscsi_conn *conn; /* used connection */
7996a778 123
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124 /* state set/tested under session->lock */
125 int state;
60ecebf5 126 atomic_t refcount;
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127 struct list_head running; /* running cmd list */
128 void *dd_data; /* driver/transport data */
129};
130
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131static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
132{
133 return task->unsol_r2t.data_length > task->unsol_r2t.sent;
134}
135
9c19a7d0 136static inline void* iscsi_next_hdr(struct iscsi_task *task)
004d6530 137{
9c19a7d0 138 return (void*)task->hdr + task->hdr_len;
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139}
140
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141/* Connection's states */
142enum {
143 ISCSI_CONN_INITIAL_STAGE,
144 ISCSI_CONN_STARTED,
145 ISCSI_CONN_STOPPED,
146 ISCSI_CONN_CLEANUP_WAIT,
147};
148
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149struct iscsi_conn {
150 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
151 void *dd_data; /* iscsi_transport data */
152 struct iscsi_session *session; /* parent session */
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153 /*
154 * conn_stop() flag: stop to recover, stop to terminate
155 */
156 int stop_stage;
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157 struct timer_list transport_timer;
158 unsigned long last_recv;
159 unsigned long last_ping;
160 int ping_timeout;
161 int recv_timeout;
9c19a7d0 162 struct iscsi_task *ping_task;
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163
164 /* iSCSI connection-wide sequencing */
165 uint32_t exp_statsn;
166
167 /* control data */
168 int id; /* CID */
7996a778 169 int c_stage; /* connection state */
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170 /*
171 * Preallocated buffer for pdus that have data but do not
172 * originate from scsi-ml. We never have two pdus using the
173 * buffer at the same time. It is only allocated to
174 * the default max recv size because the pdus we support
175 * should always fit in this buffer
176 */
177 char *data;
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178 struct iscsi_task *login_task; /* mtask used for login/text */
179 struct iscsi_task *task; /* xmit task in progress */
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180
181 /* xmit */
843c0a8a 182 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
7996a778 183 struct list_head mgmt_run_list; /* list of control tasks */
b6c395ed 184 struct list_head xmitqueue; /* data-path cmd queue */
7996a778 185 struct list_head run_list; /* list of cmds in progress */
843c0a8a 186 struct list_head requeue; /* tasks needing another run */
7996a778 187 struct work_struct xmitwork; /* per-conn. xmit workqueue */
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188 unsigned long suspend_tx; /* suspend Tx */
189 unsigned long suspend_rx; /* suspend Rx */
190
191 /* abort */
192 wait_queue_head_t ehwait; /* used in eh_abort() */
193 struct iscsi_tm tmhdr;
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194 struct timer_list tmf_timer;
195 int tmf_state; /* see TMF_INITIAL, etc.*/
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196
197 /* negotiated params */
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198 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
199 unsigned max_xmit_dlength; /* target_max_recv_dsl */
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200 int hdrdgst_en;
201 int datadgst_en;
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202 int ifmarker_en;
203 int ofmarker_en;
204 /* values userspace uses to id a conn */
205 int persistent_port;
206 char *persistent_address;
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207 /* remote portal currently connected to */
208 int portal_port;
209 char portal_address[ISCSI_ADDRESS_BUF_LEN];
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210
211 /* MIB-statistics */
212 uint64_t txdata_octets;
213 uint64_t rxdata_octets;
214 uint32_t scsicmd_pdus_cnt;
215 uint32_t dataout_pdus_cnt;
216 uint32_t scsirsp_pdus_cnt;
217 uint32_t datain_pdus_cnt;
218 uint32_t r2t_pdus_cnt;
219 uint32_t tmfcmd_pdus_cnt;
220 int32_t tmfrsp_pdus_cnt;
221
222 /* custom statistics */
223 uint32_t eh_abort_cnt;
87528227 224 uint32_t fmr_unalign_cnt;
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225};
226
6320377f 227struct iscsi_pool {
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228 struct kfifo *queue; /* FIFO Queue */
229 void **pool; /* Pool of elements */
230 int max; /* Max number of elements */
231};
232
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233/* Session's states */
234enum {
235 ISCSI_STATE_FREE = 1,
236 ISCSI_STATE_LOGGED_IN,
237 ISCSI_STATE_FAILED,
238 ISCSI_STATE_TERMINATE,
239 ISCSI_STATE_IN_RECOVERY,
240 ISCSI_STATE_RECOVERY_FAILED,
241 ISCSI_STATE_LOGGING_OUT,
242};
243
7996a778 244struct iscsi_session {
75613521 245 struct iscsi_cls_session *cls_session;
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246 /*
247 * Syncs up the scsi eh thread with the iscsi eh thread when sending
248 * task management functions. This must be taken before the session
249 * and recv lock.
250 */
251 struct mutex eh_mutex;
252
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253 /* iSCSI session-wide sequencing */
254 uint32_t cmdsn;
255 uint32_t exp_cmdsn;
256 uint32_t max_cmdsn;
257
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258 /* This tracks the reqs queued into the initiator */
259 uint32_t queued_cmdsn;
260
7996a778 261 /* configuration */
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262 int abort_timeout;
263 int lu_reset_timeout;
7996a778 264 int initial_r2t_en;
857ae0bd 265 unsigned max_r2t;
7996a778 266 int imm_data_en;
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267 unsigned first_burst;
268 unsigned max_burst;
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269 int time2wait;
270 int time2retain;
271 int pdu_inorder_en;
272 int dataseq_inorder_en;
273 int erl;
843c0a8a 274 int fast_abort;
a54a52ca 275 int tpgt;
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276 char *username;
277 char *username_in;
278 char *password;
279 char *password_in;
a54a52ca 280 char *targetname;
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281 char *ifacename;
282 char *initiatorname;
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283 /* control data */
284 struct iscsi_transport *tt;
285 struct Scsi_Host *host;
286 struct iscsi_conn *leadconn; /* leading connection */
287 spinlock_t lock; /* protects session state, *
288 * sequence numbers, *
289 * session resources: *
290 * - cmdpool, *
291 * - mgmtpool, *
292 * - r2tpool */
293 int state; /* session state */
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294 int age; /* counts session re-opens */
295
3e5c28ad 296 int scsi_cmds_max; /* max scsi commands */
7996a778 297 int cmds_max; /* size of cmds array */
9c19a7d0 298 struct iscsi_task **cmds; /* Original Cmds arr */
6320377f 299 struct iscsi_pool cmdpool; /* PDU's pool */
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300};
301
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302enum {
303 ISCSI_HOST_SETUP,
304 ISCSI_HOST_REMOVED,
305};
306
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307struct iscsi_host {
308 char *initiatorname;
309 /* hw address or netdev iscsi connection is bound to */
310 char *hwaddress;
311 char *netdev;
312 /* local address */
313 int local_port;
314 char local_address[ISCSI_ADDRESS_BUF_LEN];
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315
316 wait_queue_head_t session_removal_wq;
317 /* protects sessions and state */
318 spinlock_t lock;
319 int num_sessions;
320 int state;
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321
322 struct workqueue_struct *workq;
323 char workq_name[20];
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324};
325
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326/*
327 * scsi host template
328 */
329extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
330extern int iscsi_eh_abort(struct scsi_cmnd *sc);
8e124525 331extern int iscsi_eh_target_reset(struct scsi_cmnd *sc);
843c0a8a 332extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
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333extern int iscsi_queuecommand(struct scsi_cmnd *sc,
334 void (*done)(struct scsi_cmnd *));
0801c242 335
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336/*
337 * iSCSI host helpers.
338 */
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339#define iscsi_host_priv(_shost) \
340 (shost_priv(_shost) + sizeof(struct iscsi_host))
341
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342extern int iscsi_host_set_param(struct Scsi_Host *shost,
343 enum iscsi_host_param param, char *buf,
344 int buflen);
345extern int iscsi_host_get_param(struct Scsi_Host *shost,
346 enum iscsi_host_param param, char *buf);
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347extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
348extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
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349 int dd_data_size, uint16_t qdepth,
350 bool xmit_can_sleep);
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351extern void iscsi_host_remove(struct Scsi_Host *shost);
352extern void iscsi_host_free(struct Scsi_Host *shost);
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353
354/*
355 * session management
356 */
357extern struct iscsi_cls_session *
75613521 358iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
7970634b 359 uint16_t, int, uint32_t, unsigned int);
7996a778 360extern void iscsi_session_teardown(struct iscsi_cls_session *);
7996a778 361extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
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362extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
363 enum iscsi_param param, char *buf, int buflen);
364extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
365 enum iscsi_param param, char *buf);
7996a778 366
322d739d 367#define iscsi_session_printk(prefix, _sess, fmt, a...) \
75613521 368 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
322d739d 369
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370/*
371 * connection management
372 */
373extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
5d91e209 374 int, uint32_t);
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375extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
376extern int iscsi_conn_start(struct iscsi_cls_conn *);
377extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
378extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
379 int);
380extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
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381extern void iscsi_session_failure(struct iscsi_cls_session *cls_session,
382 enum iscsi_err err);
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383extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
384 enum iscsi_param param, char *buf);
5af3e91d 385extern void iscsi_suspend_tx(struct iscsi_conn *conn);
32ae763e 386extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
7996a778 387
322d739d 388#define iscsi_conn_printk(prefix, _c, fmt, a...) \
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389 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
390 fmt, ##a)
322d739d 391
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392/*
393 * pdu and task processing
394 */
77a23c21 395extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
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396extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
397 struct iscsi_r2t_info *r2t,
398 struct iscsi_data *hdr);
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399extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
400 char *, uint32_t);
401extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
402 char *, int);
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403extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
404 char *, int);
0af967f5 405extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
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406extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
407extern void iscsi_requeue_task(struct iscsi_task *task);
408extern void iscsi_put_task(struct iscsi_task *task);
913e5bf4 409extern void __iscsi_get_task(struct iscsi_task *task);
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410
411/*
412 * generic helpers
413 */
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414extern void iscsi_pool_free(struct iscsi_pool *);
415extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
7996a778 416
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417/*
418 * inline functions to deal with padding.
419 */
420static inline unsigned int
421iscsi_padded(unsigned int len)
422{
423 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
424}
425
426static inline unsigned int
427iscsi_padding(unsigned int len)
428{
429 len &= (ISCSI_PAD_LEN - 1);
430 if (len)
431 len = ISCSI_PAD_LEN - len;
432 return len;
433}
434
7996a778 435#endif