xref: /openbmc/linux/drivers/nvme/host/nvme.h (revision def61eca)
1 /*
2  * Copyright (c) 2011-2014, Intel Corporation.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  */
13 
14 #ifndef _NVME_H
15 #define _NVME_H
16 
17 #include <linux/nvme.h>
18 #include <linux/pci.h>
19 #include <linux/kref.h>
20 #include <linux/blk-mq.h>
21 
22 enum {
23 	/*
24 	 * Driver internal status code for commands that were cancelled due
25 	 * to timeouts or controller shutdown.  The value is negative so
26 	 * that it a) doesn't overlap with the unsigned hardware error codes,
27 	 * and b) can easily be tested for.
28 	 */
29 	NVME_SC_CANCELLED		= -EINTR,
30 };
31 
32 extern unsigned char nvme_io_timeout;
33 #define NVME_IO_TIMEOUT	(nvme_io_timeout * HZ)
34 
35 extern unsigned char admin_timeout;
36 #define ADMIN_TIMEOUT	(admin_timeout * HZ)
37 
38 extern unsigned char shutdown_timeout;
39 #define SHUTDOWN_TIMEOUT	(shutdown_timeout * HZ)
40 
41 #define NVME_DEFAULT_KATO	5
42 #define NVME_KATO_GRACE		10
43 
44 enum {
45 	NVME_NS_LBA		= 0,
46 	NVME_NS_LIGHTNVM	= 1,
47 };
48 
49 /*
50  * List of workarounds for devices that required behavior not specified in
51  * the standard.
52  */
53 enum nvme_quirks {
54 	/*
55 	 * Prefers I/O aligned to a stripe size specified in a vendor
56 	 * specific Identify field.
57 	 */
58 	NVME_QUIRK_STRIPE_SIZE			= (1 << 0),
59 
60 	/*
61 	 * The controller doesn't handle Identify value others than 0 or 1
62 	 * correctly.
63 	 */
64 	NVME_QUIRK_IDENTIFY_CNS			= (1 << 1),
65 
66 	/*
67 	 * The controller deterministically returns O's on reads to discarded
68 	 * logical blocks.
69 	 */
70 	NVME_QUIRK_DISCARD_ZEROES		= (1 << 2),
71 };
72 
73 enum nvme_ctrl_state {
74 	NVME_CTRL_NEW,
75 	NVME_CTRL_LIVE,
76 	NVME_CTRL_RESETTING,
77 	NVME_CTRL_RECONNECTING,
78 	NVME_CTRL_DELETING,
79 	NVME_CTRL_DEAD,
80 };
81 
82 struct nvme_ctrl {
83 	enum nvme_ctrl_state state;
84 	spinlock_t lock;
85 	const struct nvme_ctrl_ops *ops;
86 	struct request_queue *admin_q;
87 	struct request_queue *connect_q;
88 	struct device *dev;
89 	struct kref kref;
90 	int instance;
91 	struct blk_mq_tag_set *tagset;
92 	struct list_head namespaces;
93 	struct mutex namespaces_mutex;
94 	struct device *device;	/* char device */
95 	struct list_head node;
96 	struct ida ns_ida;
97 
98 	char name[12];
99 	char serial[20];
100 	char model[40];
101 	char firmware_rev[8];
102 	u16 cntlid;
103 
104 	u32 ctrl_config;
105 
106 	u32 page_size;
107 	u32 max_hw_sectors;
108 	u32 stripe_size;
109 	u16 oncs;
110 	u16 vid;
111 	atomic_t abort_limit;
112 	u8 event_limit;
113 	u8 vwc;
114 	u32 vs;
115 	u32 sgls;
116 	u16 kas;
117 	unsigned int kato;
118 	bool subsystem;
119 	unsigned long quirks;
120 	struct work_struct scan_work;
121 	struct work_struct async_event_work;
122 	struct delayed_work ka_work;
123 
124 	/* Fabrics only */
125 	u16 sqsize;
126 	u32 ioccsz;
127 	u32 iorcsz;
128 	u16 icdoff;
129 	u16 maxcmd;
130 	struct nvmf_ctrl_options *opts;
131 };
132 
133 /*
134  * An NVM Express namespace is equivalent to a SCSI LUN
135  */
136 struct nvme_ns {
137 	struct list_head list;
138 
139 	struct nvme_ctrl *ctrl;
140 	struct request_queue *queue;
141 	struct gendisk *disk;
142 	struct kref kref;
143 	int instance;
144 
145 	u8 eui[8];
146 	u8 uuid[16];
147 
148 	unsigned ns_id;
149 	int lba_shift;
150 	u16 ms;
151 	bool ext;
152 	u8 pi_type;
153 	int type;
154 	unsigned long flags;
155 
156 #define NVME_NS_REMOVING 0
157 #define NVME_NS_DEAD     1
158 
159 	u64 mode_select_num_blocks;
160 	u32 mode_select_block_len;
161 };
162 
163 struct nvme_ctrl_ops {
164 	const char *name;
165 	struct module *module;
166 	bool is_fabrics;
167 	int (*reg_read32)(struct nvme_ctrl *ctrl, u32 off, u32 *val);
168 	int (*reg_write32)(struct nvme_ctrl *ctrl, u32 off, u32 val);
169 	int (*reg_read64)(struct nvme_ctrl *ctrl, u32 off, u64 *val);
170 	int (*reset_ctrl)(struct nvme_ctrl *ctrl);
171 	void (*free_ctrl)(struct nvme_ctrl *ctrl);
172 	void (*post_scan)(struct nvme_ctrl *ctrl);
173 	void (*submit_async_event)(struct nvme_ctrl *ctrl, int aer_idx);
174 	int (*delete_ctrl)(struct nvme_ctrl *ctrl);
175 	const char *(*get_subsysnqn)(struct nvme_ctrl *ctrl);
176 	int (*get_address)(struct nvme_ctrl *ctrl, char *buf, int size);
177 };
178 
179 static inline bool nvme_ctrl_ready(struct nvme_ctrl *ctrl)
180 {
181 	u32 val = 0;
182 
183 	if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &val))
184 		return false;
185 	return val & NVME_CSTS_RDY;
186 }
187 
188 static inline int nvme_reset_subsystem(struct nvme_ctrl *ctrl)
189 {
190 	if (!ctrl->subsystem)
191 		return -ENOTTY;
192 	return ctrl->ops->reg_write32(ctrl, NVME_REG_NSSR, 0x4E564D65);
193 }
194 
195 static inline u64 nvme_block_nr(struct nvme_ns *ns, sector_t sector)
196 {
197 	return (sector >> (ns->lba_shift - 9));
198 }
199 
200 static inline unsigned nvme_map_len(struct request *rq)
201 {
202 	if (req_op(rq) == REQ_OP_DISCARD)
203 		return sizeof(struct nvme_dsm_range);
204 	else
205 		return blk_rq_bytes(rq);
206 }
207 
208 static inline void nvme_cleanup_cmd(struct request *req)
209 {
210 	if (req_op(req) == REQ_OP_DISCARD)
211 		kfree(req->completion_data);
212 }
213 
214 static inline int nvme_error_status(u16 status)
215 {
216 	switch (status & 0x7ff) {
217 	case NVME_SC_SUCCESS:
218 		return 0;
219 	case NVME_SC_CAP_EXCEEDED:
220 		return -ENOSPC;
221 	default:
222 		return -EIO;
223 	}
224 }
225 
226 static inline bool nvme_req_needs_retry(struct request *req, u16 status)
227 {
228 	return !(status & NVME_SC_DNR || blk_noretry_request(req)) &&
229 		(jiffies - req->start_time) < req->timeout;
230 }
231 
232 void nvme_cancel_request(struct request *req, void *data, bool reserved);
233 bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
234 		enum nvme_ctrl_state new_state);
235 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
236 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
237 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl);
238 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
239 		const struct nvme_ctrl_ops *ops, unsigned long quirks);
240 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl);
241 void nvme_put_ctrl(struct nvme_ctrl *ctrl);
242 int nvme_init_identify(struct nvme_ctrl *ctrl);
243 
244 void nvme_queue_scan(struct nvme_ctrl *ctrl);
245 void nvme_remove_namespaces(struct nvme_ctrl *ctrl);
246 
247 #define NVME_NR_AERS	1
248 void nvme_complete_async_event(struct nvme_ctrl *ctrl,
249 		struct nvme_completion *cqe);
250 void nvme_queue_async_events(struct nvme_ctrl *ctrl);
251 
252 void nvme_stop_queues(struct nvme_ctrl *ctrl);
253 void nvme_start_queues(struct nvme_ctrl *ctrl);
254 void nvme_kill_queues(struct nvme_ctrl *ctrl);
255 
256 #define NVME_QID_ANY -1
257 struct request *nvme_alloc_request(struct request_queue *q,
258 		struct nvme_command *cmd, unsigned int flags, int qid);
259 void nvme_requeue_req(struct request *req);
260 int nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
261 		struct nvme_command *cmd);
262 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
263 		void *buf, unsigned bufflen);
264 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
265 		struct nvme_completion *cqe, void *buffer, unsigned bufflen,
266 		unsigned timeout, int qid, int at_head, int flags);
267 int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
268 		void __user *ubuffer, unsigned bufflen, u32 *result,
269 		unsigned timeout);
270 int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
271 		void __user *ubuffer, unsigned bufflen,
272 		void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
273 		u32 *result, unsigned timeout);
274 int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id);
275 int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
276 		struct nvme_id_ns **id);
277 int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log);
278 int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
279 			dma_addr_t dma_addr, u32 *result);
280 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
281 			dma_addr_t dma_addr, u32 *result);
282 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count);
283 void nvme_start_keep_alive(struct nvme_ctrl *ctrl);
284 void nvme_stop_keep_alive(struct nvme_ctrl *ctrl);
285 
286 struct sg_io_hdr;
287 
288 int nvme_sg_io(struct nvme_ns *ns, struct sg_io_hdr __user *u_hdr);
289 int nvme_sg_io32(struct nvme_ns *ns, unsigned long arg);
290 int nvme_sg_get_version_num(int __user *ip);
291 
292 #ifdef CONFIG_NVM
293 int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id);
294 int nvme_nvm_register(struct request_queue *q, char *disk_name);
295 void nvme_nvm_unregister(struct request_queue *q, char *disk_name);
296 #else
297 static inline int nvme_nvm_register(struct request_queue *q, char *disk_name)
298 {
299 	return 0;
300 }
301 
302 static inline void nvme_nvm_unregister(struct request_queue *q, char *disk_name) {};
303 
304 static inline int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
305 {
306 	return 0;
307 }
308 #endif /* CONFIG_NVM */
309 
310 int __init nvme_core_init(void);
311 void nvme_core_exit(void);
312 
313 #endif /* _NVME_H */
314