• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * iSER transport for the Open iSCSI Initiator & iSER transport internals
3  *
4  * Copyright (C) 2004 Dmitry Yusupov
5  * Copyright (C) 2004 Alex Aizman
6  * Copyright (C) 2005 Mike Christie
7  * based on code maintained by open-iscsi@googlegroups.com
8  *
9  * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
10  * Copyright (c) 2005, 2006 Cisco Systems.  All rights reserved.
11  *
12  * This software is available to you under a choice of one of two
13  * licenses.  You may choose to be licensed under the terms of the GNU
14  * General Public License (GPL) Version 2, available from the file
15  * COPYING in the main directory of this source tree, or the
16  * OpenIB.org BSD license below:
17  *
18  *     Redistribution and use in source and binary forms, with or
19  *     without modification, are permitted provided that the following
20  *     conditions are met:
21  *
22  *	- Redistributions of source code must retain the above
23  *	  copyright notice, this list of conditions and the following
24  *	  disclaimer.
25  *
26  *	- Redistributions in binary form must reproduce the above
27  *	  copyright notice, this list of conditions and the following
28  *	  disclaimer in the documentation and/or other materials
29  *	  provided with the distribution.
30  *
31  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
34  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
35  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
36  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
37  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
38  * SOFTWARE.
39  */
40 #ifndef __ISCSI_ISER_H__
41 #define __ISCSI_ISER_H__
42 
43 #include <linux/types.h>
44 #include <linux/net.h>
45 #include <scsi/libiscsi.h>
46 #include <scsi/scsi_transport_iscsi.h>
47 
48 #include <linux/interrupt.h>
49 #include <linux/wait.h>
50 #include <linux/sched.h>
51 #include <linux/list.h>
52 #include <linux/slab.h>
53 #include <linux/dma-mapping.h>
54 #include <linux/mutex.h>
55 #include <linux/mempool.h>
56 #include <linux/uio.h>
57 
58 #include <linux/socket.h>
59 #include <linux/in.h>
60 #include <linux/in6.h>
61 
62 #include <rdma/ib_verbs.h>
63 #include <rdma/ib_fmr_pool.h>
64 #include <rdma/rdma_cm.h>
65 
66 #define DRV_NAME	"iser"
67 #define PFX		DRV_NAME ": "
68 #define DRV_VER		"0.1"
69 #define DRV_DATE	"May 7th, 2006"
70 
71 #define iser_dbg(fmt, arg...)				\
72 	do {						\
73 		if (iser_debug_level > 1)		\
74 			printk(KERN_DEBUG PFX "%s:" fmt,\
75 				__func__ , ## arg);	\
76 	} while (0)
77 
78 #define iser_warn(fmt, arg...)				\
79 	do {						\
80 		if (iser_debug_level > 0)		\
81 			printk(KERN_DEBUG PFX "%s:" fmt,\
82 				__func__ , ## arg);	\
83 	} while (0)
84 
85 #define iser_err(fmt, arg...)				\
86 	do {						\
87 		printk(KERN_ERR PFX "%s:" fmt,          \
88 		       __func__ , ## arg);		\
89 	} while (0)
90 
91 #define SHIFT_4K	12
92 #define SIZE_4K	(1ULL << SHIFT_4K)
93 #define MASK_4K	(~(SIZE_4K-1))
94 
95 					/* support up to 512KB in one RDMA */
96 #define ISCSI_ISER_SG_TABLESIZE         (0x80000 >> SHIFT_4K)
97 #define ISER_DEF_CMD_PER_LUN		128
98 
99 /* QP settings */
100 /* Maximal bounds on received asynchronous PDUs */
101 #define ISER_MAX_RX_MISC_PDUS		4 /* NOOP_IN(2) , ASYNC_EVENT(2)   */
102 
103 #define ISER_MAX_TX_MISC_PDUS		6 /* NOOP_OUT(2), TEXT(1),         *
104 					   * SCSI_TMFUNC(2), LOGOUT(1) */
105 
106 #define ISER_QP_MAX_RECV_DTOS		(ISCSI_DEF_XMIT_CMDS_MAX)
107 
108 #define ISER_MIN_POSTED_RX		(ISCSI_DEF_XMIT_CMDS_MAX >> 2)
109 
110 /* the max TX (send) WR supported by the iSER QP is defined by                 *
111  * max_send_wr = T * (1 + D) + C ; D is how many inflight dataouts we expect   *
112  * to have at max for SCSI command. The tx posting & completion handling code  *
113  * supports -EAGAIN scheme where tx is suspended till the QP has room for more *
114  * send WR. D=8 comes from 64K/8K                                              */
115 
116 #define ISER_INFLIGHT_DATAOUTS		8
117 
118 #define ISER_QP_MAX_REQ_DTOS		(ISCSI_DEF_XMIT_CMDS_MAX *    \
119 					(1 + ISER_INFLIGHT_DATAOUTS) + \
120 					ISER_MAX_TX_MISC_PDUS        + \
121 					ISER_MAX_RX_MISC_PDUS)
122 
123 #define ISER_VER			0x10
124 #define ISER_WSV			0x08
125 #define ISER_RSV			0x04
126 
127 struct iser_hdr {
128 	u8      flags;
129 	u8      rsvd[3];
130 	__be32  write_stag; /* write rkey */
131 	__be64  write_va;
132 	__be32  read_stag;  /* read rkey */
133 	__be64  read_va;
134 } __attribute__((packed));
135 
136 /* Constant PDU lengths calculations */
137 #define ISER_HEADERS_LEN  (sizeof(struct iser_hdr) + sizeof(struct iscsi_hdr))
138 
139 #define ISER_RECV_DATA_SEG_LEN	128
140 #define ISER_RX_PAYLOAD_SIZE	(ISER_HEADERS_LEN + ISER_RECV_DATA_SEG_LEN)
141 #define ISER_RX_LOGIN_SIZE	(ISER_HEADERS_LEN + ISCSI_DEF_MAX_RECV_SEG_LEN)
142 
143 /* Length of an object name string */
144 #define ISER_OBJECT_NAME_SIZE		    64
145 
146 enum iser_ib_conn_state {
147 	ISER_CONN_INIT,		   /* descriptor allocd, no conn          */
148 	ISER_CONN_PENDING,	   /* in the process of being established */
149 	ISER_CONN_UP,		   /* up and running                      */
150 	ISER_CONN_TERMINATING,	   /* in the process of being terminated  */
151 	ISER_CONN_DOWN,		   /* shut down                           */
152 	ISER_CONN_STATES_NUM
153 };
154 
155 enum iser_task_status {
156 	ISER_TASK_STATUS_INIT = 0,
157 	ISER_TASK_STATUS_STARTED,
158 	ISER_TASK_STATUS_COMPLETED
159 };
160 
161 enum iser_data_dir {
162 	ISER_DIR_IN = 0,	   /* to initiator */
163 	ISER_DIR_OUT,		   /* from initiator */
164 	ISER_DIRS_NUM
165 };
166 
167 struct iser_data_buf {
168 	void               *buf;      /* pointer to the sg list               */
169 	unsigned int       size;      /* num entries of this sg               */
170 	unsigned long      data_len;  /* total data len                       */
171 	unsigned int       dma_nents; /* returned by dma_map_sg               */
172 	char       	   *copy_buf; /* allocated copy buf for SGs unaligned *
173 	                               * for rdma which are copied            */
174 	struct scatterlist sg_single; /* SG-ified clone of a non SG SC or     *
175 				       * unaligned SG                         */
176   };
177 
178 /* fwd declarations */
179 struct iser_device;
180 struct iscsi_iser_conn;
181 struct iscsi_iser_task;
182 struct iscsi_endpoint;
183 
184 struct iser_mem_reg {
185 	u32  lkey;
186 	u32  rkey;
187 	u64  va;
188 	u64  len;
189 	void *mem_h;
190 	int  is_fmr;
191 };
192 
193 struct iser_regd_buf {
194 	struct iser_mem_reg     reg;        /* memory registration info        */
195 	void                    *virt_addr;
196 	struct iser_device      *device;    /* device->device for dma_unmap    */
197 	enum dma_data_direction direction;  /* direction for dma_unmap	       */
198 	unsigned int            data_size;
199 };
200 
201 enum iser_desc_type {
202 	ISCSI_TX_CONTROL ,
203 	ISCSI_TX_SCSI_COMMAND,
204 	ISCSI_TX_DATAOUT
205 };
206 
207 struct iser_tx_desc {
208 	struct iser_hdr              iser_header;
209 	struct iscsi_hdr             iscsi_header;
210 	enum   iser_desc_type        type;
211 	u64		             dma_addr;
212 	/* sg[0] points to iser/iscsi headers, sg[1] optionally points to either
213 	of immediate data, unsolicited data-out or control (login,text) */
214 	struct ib_sge		     tx_sg[2];
215 	int                          num_sge;
216 };
217 
218 #define ISER_RX_PAD_SIZE	(256 - (ISER_RX_PAYLOAD_SIZE + \
219 					sizeof(u64) + sizeof(struct ib_sge)))
220 struct iser_rx_desc {
221 	struct iser_hdr              iser_header;
222 	struct iscsi_hdr             iscsi_header;
223 	char		             data[ISER_RECV_DATA_SEG_LEN];
224 	u64		             dma_addr;
225 	struct ib_sge		     rx_sg;
226 	char		             pad[ISER_RX_PAD_SIZE];
227 } __attribute__((packed));
228 
229 struct iser_device {
230 	struct ib_device             *ib_device;
231 	struct ib_pd	             *pd;
232 	struct ib_cq	             *rx_cq;
233 	struct ib_cq	             *tx_cq;
234 	struct ib_mr	             *mr;
235 	struct tasklet_struct	     cq_tasklet;
236 	struct ib_event_handler      event_handler;
237 	struct list_head             ig_list; /* entry in ig devices list */
238 	int                          refcount;
239 };
240 
241 struct iser_conn {
242 	struct iscsi_iser_conn       *iser_conn; /* iser conn for upcalls  */
243 	struct iscsi_endpoint	     *ep;
244 	enum iser_ib_conn_state	     state;	    /* rdma connection state   */
245 	atomic_t		     refcount;
246 	spinlock_t		     lock;	    /* used for state changes  */
247 	struct iser_device           *device;       /* device context          */
248 	struct rdma_cm_id            *cma_id;       /* CMA ID		       */
249 	struct ib_qp	             *qp;           /* QP 		       */
250 	struct ib_fmr_pool           *fmr_pool;     /* pool of IB FMRs         */
251 	wait_queue_head_t	     wait;          /* waitq for conn/disconn  */
252 	int                          post_recv_buf_count; /* posted rx count  */
253 	atomic_t                     post_send_buf_count; /* posted tx count   */
254 	char 			     name[ISER_OBJECT_NAME_SIZE];
255 	struct iser_page_vec         *page_vec;     /* represents SG to fmr maps*
256 						     * maps serialized as tx is*/
257 	struct list_head	     conn_list;       /* entry in ig conn list */
258 
259 	char  			     *login_buf;
260 	char			     *login_req_buf, *login_resp_buf;
261 	u64			     login_req_dma, login_resp_dma;
262 	unsigned int 		     rx_desc_head;
263 	struct iser_rx_desc	     *rx_descs;
264 	struct ib_recv_wr	     rx_wr[ISER_MIN_POSTED_RX];
265 };
266 
267 struct iscsi_iser_conn {
268 	struct iscsi_conn            *iscsi_conn;/* ptr to iscsi conn */
269 	struct iser_conn             *ib_conn;   /* iSER IB conn      */
270 };
271 
272 struct iscsi_iser_task {
273 	struct iser_tx_desc          desc;
274 	struct iscsi_iser_conn	     *iser_conn;
275 	enum iser_task_status 	     status;
276 	int                          command_sent;  /* set if command  sent  */
277 	int                          dir[ISER_DIRS_NUM];      /* set if dir use*/
278 	struct iser_regd_buf         rdma_regd[ISER_DIRS_NUM];/* regd rdma buf */
279 	struct iser_data_buf         data[ISER_DIRS_NUM];     /* orig. data des*/
280 	struct iser_data_buf         data_copy[ISER_DIRS_NUM];/* contig. copy  */
281 };
282 
283 struct iser_page_vec {
284 	u64 *pages;
285 	int length;
286 	int offset;
287 	int data_size;
288 };
289 
290 struct iser_global {
291 	struct mutex      device_list_mutex;/*                   */
292 	struct list_head  device_list;	     /* all iSER devices */
293 	struct mutex      connlist_mutex;
294 	struct list_head  connlist;		/* all iSER IB connections */
295 
296 	struct kmem_cache *desc_cache;
297 };
298 
299 extern struct iser_global ig;
300 extern int iser_debug_level;
301 
302 /* allocate connection resources needed for rdma functionality */
303 int iser_conn_set_full_featured_mode(struct iscsi_conn *conn);
304 
305 int iser_send_control(struct iscsi_conn *conn,
306 		      struct iscsi_task *task);
307 
308 int iser_send_command(struct iscsi_conn *conn,
309 		      struct iscsi_task *task);
310 
311 int iser_send_data_out(struct iscsi_conn *conn,
312 		       struct iscsi_task *task,
313 		       struct iscsi_data *hdr);
314 
315 void iscsi_iser_recv(struct iscsi_conn *conn,
316 		     struct iscsi_hdr       *hdr,
317 		     char                   *rx_data,
318 		     int                    rx_data_len);
319 
320 void iser_conn_init(struct iser_conn *ib_conn);
321 
322 void iser_conn_get(struct iser_conn *ib_conn);
323 
324 int iser_conn_put(struct iser_conn *ib_conn, int destroy_cma_id_allowed);
325 
326 void iser_conn_terminate(struct iser_conn *ib_conn);
327 
328 void iser_rcv_completion(struct iser_rx_desc *desc,
329 			 unsigned long    dto_xfer_len,
330 			struct iser_conn *ib_conn);
331 
332 void iser_snd_completion(struct iser_tx_desc *desc, struct iser_conn *ib_conn);
333 
334 void iser_task_rdma_init(struct iscsi_iser_task *task);
335 
336 void iser_task_rdma_finalize(struct iscsi_iser_task *task);
337 
338 void iser_free_rx_descriptors(struct iser_conn *ib_conn);
339 
340 void iser_finalize_rdma_unaligned_sg(struct iscsi_iser_task *task,
341 				     enum iser_data_dir         cmd_dir);
342 
343 int  iser_reg_rdma_mem(struct iscsi_iser_task *task,
344 		       enum   iser_data_dir        cmd_dir);
345 
346 int  iser_connect(struct iser_conn   *ib_conn,
347 		  struct sockaddr_in *src_addr,
348 		  struct sockaddr_in *dst_addr,
349 		  int                non_blocking);
350 
351 int  iser_reg_page_vec(struct iser_conn     *ib_conn,
352 		       struct iser_page_vec *page_vec,
353 		       struct iser_mem_reg  *mem_reg);
354 
355 void iser_unreg_mem(struct iser_mem_reg *mem_reg);
356 
357 int  iser_post_recvl(struct iser_conn *ib_conn);
358 int  iser_post_recvm(struct iser_conn *ib_conn, int count);
359 int  iser_post_send(struct iser_conn *ib_conn, struct iser_tx_desc *tx_desc);
360 
361 int iser_dma_map_task_data(struct iscsi_iser_task *iser_task,
362 			    struct iser_data_buf       *data,
363 			    enum   iser_data_dir       iser_dir,
364 			    enum   dma_data_direction  dma_dir);
365 
366 void iser_dma_unmap_task_data(struct iscsi_iser_task *iser_task);
367 int  iser_initialize_task_headers(struct iscsi_task *task,
368 			struct iser_tx_desc *tx_desc);
369 int iser_alloc_rx_descriptors(struct iser_conn *ib_conn);
370 #endif
371