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
46struct 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
52struct 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
74struct format_code {
75	u8 reserved;
76	u8 buffers;
77};
78
79struct 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 */
108struct 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
121struct 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
138enum 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
146struct 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
154struct 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
172struct ibmvscsis_nexus {
173	struct se_session *se_sess;
174};
175
176struct 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
193struct 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