1 /*
2 * Copyright (c) 2005 Cisco Systems. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
13 *
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
17 *
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 */
32
33 #ifndef IB_SRP_H
34 #define IB_SRP_H
35
36 #include <linux/types.h>
37 #include <linux/list.h>
38 #include <linux/mutex.h>
39 #include <linux/scatterlist.h>
40
41 #include <scsi/scsi_host.h>
42 #include <scsi/scsi_cmnd.h>
43
44 #include <rdma/ib_verbs.h>
45 #include <rdma/ib_sa.h>
46 #include <rdma/ib_cm.h>
47 #include <rdma/ib_fmr_pool.h>
48 #include <rdma/rdma_cm.h>
49
50 enum {
51 SRP_PATH_REC_TIMEOUT_MS = 1000,
52 SRP_ABORT_TIMEOUT_MS = 5000,
53
54 SRP_PORT_REDIRECT = 1,
55 SRP_DLID_REDIRECT = 2,
56 SRP_STALE_CONN = 3,
57
58 SRP_DEF_SG_TABLESIZE = 12,
59
60 SRP_DEFAULT_QUEUE_SIZE = 1 << 6,
61 SRP_RSP_SQ_SIZE = 1,
62 SRP_TSK_MGMT_SQ_SIZE = 1,
63 SRP_DEFAULT_CMD_SQ_SIZE = SRP_DEFAULT_QUEUE_SIZE - SRP_RSP_SQ_SIZE -
64 SRP_TSK_MGMT_SQ_SIZE,
65
66 SRP_TAG_NO_REQ = ~0U,
67 SRP_TAG_TSK_MGMT = 1U << 31,
68
69 SRP_MAX_PAGES_PER_MR = 512,
70
71 SRP_MAX_ADD_CDB_LEN = 16,
72
73 SRP_MAX_IMM_SGE = 2,
74 SRP_MAX_SGE = SRP_MAX_IMM_SGE + 1,
75 /*
76 * Choose the immediate data offset such that a 32 byte CDB still fits.
77 */
78 SRP_IMM_DATA_OFFSET = sizeof(struct srp_cmd) +
79 SRP_MAX_ADD_CDB_LEN +
80 sizeof(struct srp_imm_buf),
81 };
82
83 enum srp_target_state {
84 SRP_TARGET_SCANNING,
85 SRP_TARGET_LIVE,
86 SRP_TARGET_REMOVED,
87 };
88
89 enum srp_iu_type {
90 SRP_IU_CMD,
91 SRP_IU_TSK_MGMT,
92 SRP_IU_RSP,
93 };
94
95 /*
96 * @mr_page_mask: HCA memory registration page mask.
97 * @mr_page_size: HCA memory registration page size.
98 * @mr_max_size: Maximum size in bytes of a single FMR / FR registration
99 * request.
100 */
101 struct srp_device {
102 struct list_head dev_list;
103 struct ib_device *dev;
104 struct ib_pd *pd;
105 u32 global_rkey;
106 u64 mr_page_mask;
107 int mr_page_size;
108 int mr_max_size;
109 int max_pages_per_mr;
110 bool has_fmr;
111 bool has_fr;
112 bool use_fmr;
113 bool use_fast_reg;
114 };
115
116 struct srp_host {
117 struct srp_device *srp_dev;
118 u8 port;
119 struct device dev;
120 struct list_head target_list;
121 spinlock_t target_lock;
122 struct completion released;
123 struct list_head list;
124 struct mutex add_target_mutex;
125 };
126
127 struct srp_request {
128 struct scsi_cmnd *scmnd;
129 struct srp_iu *cmd;
130 union {
131 struct ib_pool_fmr **fmr_list;
132 struct srp_fr_desc **fr_list;
133 };
134 u64 *map_page;
135 struct srp_direct_buf *indirect_desc;
136 dma_addr_t indirect_dma_addr;
137 short nmdesc;
138 struct ib_cqe reg_cqe;
139 };
140
141 /**
142 * struct srp_rdma_ch
143 * @comp_vector: Completion vector used by this RDMA channel.
144 * @max_it_iu_len: Maximum initiator-to-target information unit length.
145 * @max_ti_iu_len: Maximum target-to-initiator information unit length.
146 */
147 struct srp_rdma_ch {
148 /* These are RW in the hot path, and commonly used together */
149 struct list_head free_tx;
150 spinlock_t lock;
151 s32 req_lim;
152
153 /* These are read-only in the hot path */
154 struct srp_target_port *target ____cacheline_aligned_in_smp;
155 struct ib_cq *send_cq;
156 struct ib_cq *recv_cq;
157 struct ib_qp *qp;
158 union {
159 struct ib_fmr_pool *fmr_pool;
160 struct srp_fr_pool *fr_pool;
161 };
162 uint32_t max_it_iu_len;
163 uint32_t max_ti_iu_len;
164 bool use_imm_data;
165
166 /* Everything above this point is used in the hot path of
167 * command processing. Try to keep them packed into cachelines.
168 */
169
170 struct completion done;
171 int status;
172
173 union {
174 struct ib_cm {
175 struct sa_path_rec path;
176 struct ib_sa_query *path_query;
177 int path_query_id;
178 struct ib_cm_id *cm_id;
179 } ib_cm;
180 struct rdma_cm {
181 struct rdma_cm_id *cm_id;
182 } rdma_cm;
183 };
184
185 struct srp_iu **tx_ring;
186 struct srp_iu **rx_ring;
187 struct srp_request *req_ring;
188 int comp_vector;
189
190 u64 tsk_mgmt_tag;
191 struct completion tsk_mgmt_done;
192 u8 tsk_mgmt_status;
193 bool connected;
194 };
195
196 /**
197 * struct srp_target_port
198 * @comp_vector: Completion vector used by the first RDMA channel created for
199 * this target port.
200 */
201 struct srp_target_port {
202 /* read and written in the hot path */
203 spinlock_t lock;
204
205 /* read only in the hot path */
206 u32 global_rkey;
207 struct srp_rdma_ch *ch;
208 struct net *net;
209 u32 ch_count;
210 u32 lkey;
211 enum srp_target_state state;
212 unsigned int cmd_sg_cnt;
213 unsigned int indirect_size;
214 bool allow_ext_sg;
215
216 /* other member variables */
217 union ib_gid sgid;
218 __be64 id_ext;
219 __be64 ioc_guid;
220 __be64 initiator_ext;
221 u16 io_class;
222 struct srp_host *srp_host;
223 struct Scsi_Host *scsi_host;
224 struct srp_rport *rport;
225 char target_name[32];
226 unsigned int scsi_id;
227 unsigned int sg_tablesize;
228 unsigned int target_can_queue;
229 int mr_pool_size;
230 int mr_per_cmd;
231 int queue_size;
232 int req_ring_size;
233 int comp_vector;
234 int tl_retry_count;
235
236 bool using_rdma_cm;
237
238 union {
239 struct {
240 __be64 service_id;
241 union ib_gid orig_dgid;
242 __be16 pkey;
243 } ib_cm;
244 struct {
245 union {
246 struct sockaddr_in ip4;
247 struct sockaddr_in6 ip6;
248 struct sockaddr_storage ss;
249 } src;
250 union {
251 struct sockaddr_in ip4;
252 struct sockaddr_in6 ip6;
253 struct sockaddr_storage ss;
254 } dst;
255 bool src_specified;
256 } rdma_cm;
257 };
258
259 u32 rq_tmo_jiffies;
260
261 int zero_req_lim;
262
263 struct work_struct tl_err_work;
264 struct work_struct remove_work;
265
266 struct list_head list;
267 bool qp_in_error;
268 };
269
270 struct srp_iu {
271 struct list_head list;
272 u64 dma;
273 void *buf;
274 size_t size;
275 enum dma_data_direction direction;
276 u32 num_sge;
277 struct ib_sge sge[SRP_MAX_SGE];
278 struct ib_cqe cqe;
279 };
280
281 /**
282 * struct srp_fr_desc - fast registration work request arguments
283 * @entry: Entry in srp_fr_pool.free_list.
284 * @mr: Memory region.
285 * @frpl: Fast registration page list.
286 */
287 struct srp_fr_desc {
288 struct list_head entry;
289 struct ib_mr *mr;
290 };
291
292 /**
293 * struct srp_fr_pool - pool of fast registration descriptors
294 *
295 * An entry is available for allocation if and only if it occurs in @free_list.
296 *
297 * @size: Number of descriptors in this pool.
298 * @max_page_list_len: Maximum fast registration work request page list length.
299 * @lock: Protects free_list.
300 * @free_list: List of free descriptors.
301 * @desc: Fast registration descriptor pool.
302 */
303 struct srp_fr_pool {
304 int size;
305 int max_page_list_len;
306 spinlock_t lock;
307 struct list_head free_list;
308 struct srp_fr_desc desc[0];
309 };
310
311 /**
312 * struct srp_map_state - per-request DMA memory mapping state
313 * @desc: Pointer to the element of the SRP buffer descriptor array
314 * that is being filled in.
315 * @pages: Array with DMA addresses of pages being considered for
316 * memory registration.
317 * @base_dma_addr: DMA address of the first page that has not yet been mapped.
318 * @dma_len: Number of bytes that will be registered with the next
319 * FMR or FR memory registration call.
320 * @total_len: Total number of bytes in the sg-list being mapped.
321 * @npages: Number of page addresses in the pages[] array.
322 * @nmdesc: Number of FMR or FR memory descriptors used for mapping.
323 * @ndesc: Number of SRP buffer descriptors that have been filled in.
324 */
325 struct srp_map_state {
326 union {
327 struct {
328 struct ib_pool_fmr **next;
329 struct ib_pool_fmr **end;
330 } fmr;
331 struct {
332 struct srp_fr_desc **next;
333 struct srp_fr_desc **end;
334 } fr;
335 struct {
336 void **next;
337 void **end;
338 } gen;
339 };
340 struct srp_direct_buf *desc;
341 union {
342 u64 *pages;
343 struct scatterlist *sg;
344 };
345 dma_addr_t base_dma_addr;
346 u32 dma_len;
347 u32 total_len;
348 unsigned int npages;
349 unsigned int nmdesc;
350 unsigned int ndesc;
351 };
352
353 #endif /* IB_SRP_H */