xref: /linux/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.h (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*******************************************************************************
3  * IBM Virtual SCSI Target Driver
4  * Copyright (C) 2003-2005 Dave Boutcher (boutcher@us.ibm.com) IBM Corp.
5  *			   Santiago Leon (santil@us.ibm.com) IBM Corp.
6  *			   Linda Xie (lxie@us.ibm.com) IBM Corp.
7  *
8  * Copyright (C) 2005-2011 FUJITA Tomonori <tomof@acm.org>
9  * Copyright (C) 2010 Nicholas A. Bellinger <nab@kernel.org>
10  * Copyright (C) 2016 Bryant G. Ly <bryantly@linux.vnet.ibm.com> IBM Corp.
11  *
12  * Authors: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
13  * Authors: Michael Cyr <mikecyr@linux.vnet.ibm.com>
14  *
15  ****************************************************************************/
16 
17 #ifndef __H_IBMVSCSI_TGT
18 #define __H_IBMVSCSI_TGT
19 
20 #include <linux/interrupt.h>
21 #include "libsrp.h"
22 
23 #define SYS_ID_NAME_LEN		64
24 #define PARTITION_NAMELEN	96
25 #define IBMVSCSIS_NAMELEN       32
26 
27 #define MSG_HI  0
28 #define MSG_LOW 1
29 
30 #define MAX_CMD_Q_PAGES       4
31 #define CRQ_PER_PAGE          (PAGE_SIZE / sizeof(struct viosrp_crq))
32 /* in terms of number of elements */
33 #define DEFAULT_CMD_Q_SIZE    CRQ_PER_PAGE
34 #define MAX_CMD_Q_SIZE        (DEFAULT_CMD_Q_SIZE * MAX_CMD_Q_PAGES)
35 
36 #define SRP_VIOLATION           0x102  /* general error code */
37 
38 /*
39  * SRP buffer formats defined as of 16.a supported by this driver.
40  */
41 #define SUPPORTED_FORMATS  ((SRP_DATA_DESC_DIRECT << 1) | \
42 			    (SRP_DATA_DESC_INDIRECT << 1))
43 
44 #define SCSI_LUN_ADDR_METHOD_FLAT	1
45 
46 struct dma_window {
47 	u32 liobn;	/* Unique per vdevice */
48 	u64 tce_base;	/* Physical location of the TCE table */
49 	u64 tce_size;	/* Size of the TCE table in bytes */
50 };
51 
52 struct target_dds {
53 	u64 unit_id;                /* 64 bit will force alignment */
54 #define NUM_DMA_WINDOWS 2
55 #define LOCAL  0
56 #define REMOTE 1
57 	struct dma_window  window[NUM_DMA_WINDOWS];
58 
59 	/* root node property "ibm,partition-no" */
60 	uint partition_num;
61 	char partition_name[PARTITION_NAMELEN];
62 };
63 
64 #define MAX_NUM_PORTS        1
65 #define MAX_H_COPY_RDMA      (128 * 1024)
66 
67 #define MAX_EYE   64
68 
69 /* Return codes */
70 #define ADAPT_SUCCESS            0L
71 /* choose error codes that do not conflict with PHYP */
72 #define ERROR                   -40L
73 
74 struct format_code {
75 	u8 reserved;
76 	u8 buffers;
77 };
78 
79 struct client_info {
80 #define SRP_VERSION "16.a"
81 	char srp_version[8];
82 	/* root node property ibm,partition-name */
83 	char partition_name[PARTITION_NAMELEN];
84 	/* root node property ibm,partition-no */
85 	u32 partition_number;
86 	/* initially 1 */
87 	u32 mad_version;
88 	u32 os_type;
89 };
90 
91 /*
92  * Changing this constant changes the number of seconds to wait before
93  * considering the client will never service its queue again.
94  */
95 #define SECONDS_TO_CONSIDER_FAILED 30
96 /*
97  * These constants set the polling period used to determine if the client
98  * has freed at least one element in the response queue.
99  */
100 #define WAIT_SECONDS 1
101 #define WAIT_NANO_SECONDS 5000
102 #define MAX_TIMER_POPS ((1000000 / WAIT_NANO_SECONDS) * \
103 			SECONDS_TO_CONSIDER_FAILED)
104 /*
105  * general purpose timer control block
106  * which can be used for multiple functions
107  */
108 struct timer_cb {
109 	struct hrtimer timer;
110 	/*
111 	 * how long has it been since the client
112 	 * serviced the queue. The variable is incrmented
113 	 * in the service_wait_q routine and cleared
114 	 * in send messages
115 	 */
116 	int timer_pops;
117 	/* the timer is started */
118 	bool started;
119 };
120 
121 struct cmd_queue {
122 	/* kva */
123 	struct viosrp_crq *base_addr;
124 	dma_addr_t crq_token;
125 	/* used to maintain index */
126 	uint mask;
127 	/* current element */
128 	uint index;
129 	int size;
130 };
131 
132 #define SCSOLNT_RESP_SHIFT	1
133 #define UCSOLNT_RESP_SHIFT	2
134 
135 #define SCSOLNT         BIT(SCSOLNT_RESP_SHIFT)
136 #define UCSOLNT         BIT(UCSOLNT_RESP_SHIFT)
137 
138 enum cmd_type {
139 	SCSI_CDB	= 0x01,
140 	TASK_MANAGEMENT	= 0x02,
141 	/* MAD or addressed to port 0 */
142 	ADAPTER_MAD	= 0x04,
143 	UNSET_TYPE	= 0x08,
144 };
145 
146 struct iu_rsp {
147 	u8 format;
148 	u8 sol_not;
149 	u16 len;
150 	/* tag is just to help client identify cmd, so don't translate be/le */
151 	u64 tag;
152 };
153 
154 struct ibmvscsis_cmd {
155 	struct list_head list;
156 	/* Used for TCM Core operations */
157 	struct se_cmd se_cmd;
158 	struct iu_entry *iue;
159 	struct iu_rsp rsp;
160 	struct work_struct work;
161 	struct scsi_info *adapter;
162 	struct ibmvscsis_cmd *abort_cmd;
163 	/* Sense buffer that will be mapped into outgoing status */
164 	unsigned char sense_buf[TRANSPORT_SENSE_BUFFER];
165 	u64 init_time;
166 #define CMD_FAST_FAIL	BIT(0)
167 #define DELAY_SEND	BIT(1)
168 	u32 flags;
169 	char type;
170 };
171 
172 struct ibmvscsis_nexus {
173 	struct se_session *se_sess;
174 };
175 
176 struct ibmvscsis_tport {
177 	/* SCSI protocol the tport is providing */
178 	u8 tport_proto_id;
179 	/* ASCII formatted WWPN for SRP Target port */
180 	char tport_name[IBMVSCSIS_NAMELEN];
181 	/* Returned by ibmvscsis_make_tport() */
182 	struct se_wwn tport_wwn;
183 	/* Returned by ibmvscsis_make_tpg() */
184 	struct se_portal_group se_tpg;
185 	/* ibmvscsis port target portal group tag for TCM */
186 	u16 tport_tpgt;
187 	/* Pointer to TCM session for I_T Nexus */
188 	struct ibmvscsis_nexus *ibmv_nexus;
189 	bool enabled;
190 	bool releasing;
191 };
192 
193 struct scsi_info {
194 	struct list_head list;
195 	char eye[MAX_EYE];
196 
197 	/* commands waiting for space on repsonse queue */
198 	struct list_head waiting_rsp;
199 #define NO_QUEUE                    0x00
200 #define WAIT_ENABLED                0X01
201 #define WAIT_CONNECTION             0x04
202 	/* have established a connection */
203 #define CONNECTED                   0x08
204 	/* at least one port is processing SRP IU */
205 #define SRP_PROCESSING              0x10
206 	/* remove request received */
207 #define UNCONFIGURING               0x20
208 	/* disconnect by letting adapter go idle, no error */
209 #define WAIT_IDLE                   0x40
210 	/* disconnecting to clear an error */
211 #define ERR_DISCONNECT              0x80
212 	/* disconnect to clear error state, then come back up */
213 #define ERR_DISCONNECT_RECONNECT    0x100
214 	/* disconnected after clearing an error */
215 #define ERR_DISCONNECTED            0x200
216 	/* A series of errors caused unexpected errors */
217 #define UNDEFINED                   0x400
218 	u16  state;
219 	int fast_fail;
220 	struct target_dds dds;
221 	char *cmd_pool;
222 	/* list of free commands */
223 	struct list_head free_cmd;
224 	/* command elements ready for scheduler */
225 	struct list_head schedule_q;
226 	/* commands sent to TCM */
227 	struct list_head active_q;
228 	caddr_t *map_buf;
229 	/* ioba of map buffer */
230 	dma_addr_t map_ioba;
231 	/* allowable number of outstanding SRP requests */
232 	int request_limit;
233 	/* extra credit */
234 	int credit;
235 	/* outstanding transactions against credit limit */
236 	int debit;
237 
238 	/* allow only one outstanding mad request */
239 #define PROCESSING_MAD                0x00002
240 	/* Waiting to go idle */
241 #define WAIT_FOR_IDLE		      0x00004
242 	/* H_REG_CRQ called */
243 #define CRQ_CLOSED                    0x00010
244 	/* detected that client has failed */
245 #define CLIENT_FAILED                 0x00040
246 	/* detected that transport event occurred */
247 #define TRANS_EVENT                   0x00080
248 	/* don't attempt to send anything to the client */
249 #define RESPONSE_Q_DOWN               0x00100
250 	/* request made to schedule disconnect handler */
251 #define SCHEDULE_DISCONNECT           0x00400
252 	/* disconnect handler is scheduled */
253 #define DISCONNECT_SCHEDULED          0x00800
254 	/* remove function is sleeping */
255 #define CFG_SLEEPING                  0x01000
256 	/* Register for Prepare for Suspend Transport Events */
257 #define PREP_FOR_SUSPEND_ENABLED      0x02000
258 	/* Prepare for Suspend event sent */
259 #define PREP_FOR_SUSPEND_PENDING      0x04000
260 	/* Resume from Suspend event sent */
261 #define PREP_FOR_SUSPEND_ABORTED      0x08000
262 	/* Prepare for Suspend event overwrote another CRQ entry */
263 #define PREP_FOR_SUSPEND_OVERWRITE    0x10000
264 	u32 flags;
265 	/* adapter lock */
266 	spinlock_t intr_lock;
267 	/* information needed to manage command queue */
268 	struct cmd_queue cmd_q;
269 	/* used in hcall to copy response back into srp buffer */
270 	u64  empty_iu_id;
271 	/* used in crq, to tag what iu the response is for */
272 	u64  empty_iu_tag;
273 	uint new_state;
274 	uint resume_state;
275 	/* control block for the response queue timer */
276 	struct timer_cb rsp_q_timer;
277 	/* keep last client to enable proper accounting */
278 	struct client_info client_data;
279 	/* what can this client do */
280 	u32 client_cap;
281 	/*
282 	 * The following two fields capture state and flag changes that
283 	 * can occur when the lock is given up.  In the orginal design,
284 	 * the lock was held during calls into phyp;
285 	 * however, phyp did not meet PAPR architecture.  This is
286 	 * a work around.
287 	 */
288 	u16  phyp_acr_state;
289 	u32 phyp_acr_flags;
290 
291 	struct workqueue_struct *work_q;
292 	struct completion wait_idle;
293 	struct completion unconfig;
294 	struct device dev;
295 	struct vio_dev *dma_dev;
296 	struct srp_target target;
297 	struct ibmvscsis_tport tport;
298 	struct tasklet_struct work_task;
299 	struct work_struct proc_work;
300 };
301 
302 /*
303  * Provide a constant that allows software to detect the adapter is
304  * disconnecting from the client from one of several states.
305  */
306 #define IS_DISCONNECTING (UNCONFIGURING | ERR_DISCONNECT_RECONNECT | \
307 			  ERR_DISCONNECT)
308 
309 /*
310  * Provide a constant that can be used with interrupt handling that
311  * essentially lets the interrupt handler know that all requests should
312  * be thrown out,
313  */
314 #define DONT_PROCESS_STATE (IS_DISCONNECTING | UNDEFINED | \
315 			    ERR_DISCONNECTED  | WAIT_IDLE)
316 
317 /*
318  * If any of these flag bits are set then do not allow the interrupt
319  * handler to schedule the off level handler.
320  */
321 #define BLOCK (DISCONNECT_SCHEDULED)
322 
323 /* State and transition events that stop the interrupt handler */
324 #define TARGET_STOP(VSCSI) (long)(((VSCSI)->state & DONT_PROCESS_STATE) | \
325 				  ((VSCSI)->flags & BLOCK))
326 
327 #define PREP_FOR_SUSPEND_FLAGS  (PREP_FOR_SUSPEND_ENABLED | \
328 				 PREP_FOR_SUSPEND_PENDING | \
329 				 PREP_FOR_SUSPEND_ABORTED | \
330 				 PREP_FOR_SUSPEND_OVERWRITE)
331 
332 /* flag bit that are not reset during disconnect */
333 #define PRESERVE_FLAG_FIELDS (PREP_FOR_SUSPEND_FLAGS)
334 
335 #define vio_iu(IUE) ((union viosrp_iu *)((IUE)->sbuf->buf))
336 
337 #define READ_CMD(cdb)	(((cdb)[0] & 0x1F) == 8)
338 #define WRITE_CMD(cdb)	(((cdb)[0] & 0x1F) == 0xA)
339 
340 #ifndef H_GET_PARTNER_INFO
341 #define H_GET_PARTNER_INFO              0x0000000000000008LL
342 #endif
343 #ifndef H_ENABLE_PREPARE_FOR_SUSPEND
344 #define H_ENABLE_PREPARE_FOR_SUSPEND    0x000000000000001DLL
345 #endif
346 #ifndef H_READY_FOR_SUSPEND
347 #define H_READY_FOR_SUSPEND             0x000000000000001ELL
348 #endif
349 
350 
351 #define h_copy_rdma(l, sa, sb, da, db) \
352 		plpar_hcall_norets(H_COPY_RDMA, l, sa, sb, da, db)
353 #define h_vioctl(u, o, a, u1, u2, u3, u4) \
354 		plpar_hcall_norets(H_VIOCTL, u, o, a, u1, u2)
355 #define h_reg_crq(ua, tok, sz) \
356 		plpar_hcall_norets(H_REG_CRQ, ua, tok, sz)
357 #define h_free_crq(ua) \
358 		plpar_hcall_norets(H_FREE_CRQ, ua)
359 #define h_send_crq(ua, d1, d2) \
360 		plpar_hcall_norets(H_SEND_CRQ, ua, d1, d2)
361 
362 #endif
363