xref: /openbmc/linux/drivers/nvme/host/nvme.h (revision bc5aa3a0)
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 extern unsigned int nvme_max_retries;
45 
46 enum {
47 	NVME_NS_LBA		= 0,
48 	NVME_NS_LIGHTNVM	= 1,
49 };
50 
51 /*
52  * List of workarounds for devices that required behavior not specified in
53  * the standard.
54  */
55 enum nvme_quirks {
56 	/*
57 	 * Prefers I/O aligned to a stripe size specified in a vendor
58 	 * specific Identify field.
59 	 */
60 	NVME_QUIRK_STRIPE_SIZE			= (1 << 0),
61 
62 	/*
63 	 * The controller doesn't handle Identify value others than 0 or 1
64 	 * correctly.
65 	 */
66 	NVME_QUIRK_IDENTIFY_CNS			= (1 << 1),
67 
68 	/*
69 	 * The controller deterministically returns O's on reads to discarded
70 	 * logical blocks.
71 	 */
72 	NVME_QUIRK_DISCARD_ZEROES		= (1 << 2),
73 
74 	/*
75 	 * The controller needs a delay before starts checking the device
76 	 * readiness, which is done by reading the NVME_CSTS_RDY bit.
77 	 */
78 	NVME_QUIRK_DELAY_BEFORE_CHK_RDY		= (1 << 3),
79 };
80 
81 /* The below value is the specific amount of delay needed before checking
82  * readiness in case of the PCI_DEVICE(0x1c58, 0x0003), which needs the
83  * NVME_QUIRK_DELAY_BEFORE_CHK_RDY quirk enabled. The value (in ms) was
84  * found empirically.
85  */
86 #define NVME_QUIRK_DELAY_AMOUNT		2000
87 
88 enum nvme_ctrl_state {
89 	NVME_CTRL_NEW,
90 	NVME_CTRL_LIVE,
91 	NVME_CTRL_RESETTING,
92 	NVME_CTRL_RECONNECTING,
93 	NVME_CTRL_DELETING,
94 	NVME_CTRL_DEAD,
95 };
96 
97 struct nvme_ctrl {
98 	enum nvme_ctrl_state state;
99 	spinlock_t lock;
100 	const struct nvme_ctrl_ops *ops;
101 	struct request_queue *admin_q;
102 	struct request_queue *connect_q;
103 	struct device *dev;
104 	struct kref kref;
105 	int instance;
106 	struct blk_mq_tag_set *tagset;
107 	struct list_head namespaces;
108 	struct mutex namespaces_mutex;
109 	struct device *device;	/* char device */
110 	struct list_head node;
111 	struct ida ns_ida;
112 
113 	char name[12];
114 	char serial[20];
115 	char model[40];
116 	char firmware_rev[8];
117 	u16 cntlid;
118 
119 	u32 ctrl_config;
120 
121 	u32 page_size;
122 	u32 max_hw_sectors;
123 	u32 stripe_size;
124 	u16 oncs;
125 	u16 vid;
126 	atomic_t abort_limit;
127 	u8 event_limit;
128 	u8 vwc;
129 	u32 vs;
130 	u32 sgls;
131 	u16 kas;
132 	unsigned int kato;
133 	bool subsystem;
134 	unsigned long quirks;
135 	struct work_struct scan_work;
136 	struct work_struct async_event_work;
137 	struct delayed_work ka_work;
138 
139 	/* Fabrics only */
140 	u16 sqsize;
141 	u32 ioccsz;
142 	u32 iorcsz;
143 	u16 icdoff;
144 	u16 maxcmd;
145 	struct nvmf_ctrl_options *opts;
146 };
147 
148 /*
149  * An NVM Express namespace is equivalent to a SCSI LUN
150  */
151 struct nvme_ns {
152 	struct list_head list;
153 
154 	struct nvme_ctrl *ctrl;
155 	struct request_queue *queue;
156 	struct gendisk *disk;
157 	struct kref kref;
158 	int instance;
159 
160 	u8 eui[8];
161 	u8 uuid[16];
162 
163 	unsigned ns_id;
164 	int lba_shift;
165 	u16 ms;
166 	bool ext;
167 	u8 pi_type;
168 	int type;
169 	unsigned long flags;
170 
171 #define NVME_NS_REMOVING 0
172 #define NVME_NS_DEAD     1
173 
174 	u64 mode_select_num_blocks;
175 	u32 mode_select_block_len;
176 };
177 
178 struct nvme_ctrl_ops {
179 	const char *name;
180 	struct module *module;
181 	bool is_fabrics;
182 	int (*reg_read32)(struct nvme_ctrl *ctrl, u32 off, u32 *val);
183 	int (*reg_write32)(struct nvme_ctrl *ctrl, u32 off, u32 val);
184 	int (*reg_read64)(struct nvme_ctrl *ctrl, u32 off, u64 *val);
185 	int (*reset_ctrl)(struct nvme_ctrl *ctrl);
186 	void (*free_ctrl)(struct nvme_ctrl *ctrl);
187 	void (*post_scan)(struct nvme_ctrl *ctrl);
188 	void (*submit_async_event)(struct nvme_ctrl *ctrl, int aer_idx);
189 	int (*delete_ctrl)(struct nvme_ctrl *ctrl);
190 	const char *(*get_subsysnqn)(struct nvme_ctrl *ctrl);
191 	int (*get_address)(struct nvme_ctrl *ctrl, char *buf, int size);
192 };
193 
194 static inline bool nvme_ctrl_ready(struct nvme_ctrl *ctrl)
195 {
196 	u32 val = 0;
197 
198 	if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &val))
199 		return false;
200 	return val & NVME_CSTS_RDY;
201 }
202 
203 static inline int nvme_reset_subsystem(struct nvme_ctrl *ctrl)
204 {
205 	if (!ctrl->subsystem)
206 		return -ENOTTY;
207 	return ctrl->ops->reg_write32(ctrl, NVME_REG_NSSR, 0x4E564D65);
208 }
209 
210 static inline u64 nvme_block_nr(struct nvme_ns *ns, sector_t sector)
211 {
212 	return (sector >> (ns->lba_shift - 9));
213 }
214 
215 static inline unsigned nvme_map_len(struct request *rq)
216 {
217 	if (req_op(rq) == REQ_OP_DISCARD)
218 		return sizeof(struct nvme_dsm_range);
219 	else
220 		return blk_rq_bytes(rq);
221 }
222 
223 static inline void nvme_cleanup_cmd(struct request *req)
224 {
225 	if (req_op(req) == REQ_OP_DISCARD)
226 		kfree(req->completion_data);
227 }
228 
229 static inline int nvme_error_status(u16 status)
230 {
231 	switch (status & 0x7ff) {
232 	case NVME_SC_SUCCESS:
233 		return 0;
234 	case NVME_SC_CAP_EXCEEDED:
235 		return -ENOSPC;
236 	default:
237 		return -EIO;
238 	}
239 }
240 
241 static inline bool nvme_req_needs_retry(struct request *req, u16 status)
242 {
243 	return !(status & NVME_SC_DNR || blk_noretry_request(req)) &&
244 		(jiffies - req->start_time) < req->timeout &&
245 		req->retries < nvme_max_retries;
246 }
247 
248 void nvme_cancel_request(struct request *req, void *data, bool reserved);
249 bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
250 		enum nvme_ctrl_state new_state);
251 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
252 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
253 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl);
254 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
255 		const struct nvme_ctrl_ops *ops, unsigned long quirks);
256 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl);
257 void nvme_put_ctrl(struct nvme_ctrl *ctrl);
258 int nvme_init_identify(struct nvme_ctrl *ctrl);
259 
260 void nvme_queue_scan(struct nvme_ctrl *ctrl);
261 void nvme_remove_namespaces(struct nvme_ctrl *ctrl);
262 
263 #define NVME_NR_AERS	1
264 void nvme_complete_async_event(struct nvme_ctrl *ctrl,
265 		struct nvme_completion *cqe);
266 void nvme_queue_async_events(struct nvme_ctrl *ctrl);
267 
268 void nvme_stop_queues(struct nvme_ctrl *ctrl);
269 void nvme_start_queues(struct nvme_ctrl *ctrl);
270 void nvme_kill_queues(struct nvme_ctrl *ctrl);
271 
272 #define NVME_QID_ANY -1
273 struct request *nvme_alloc_request(struct request_queue *q,
274 		struct nvme_command *cmd, unsigned int flags, int qid);
275 void nvme_requeue_req(struct request *req);
276 int nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
277 		struct nvme_command *cmd);
278 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
279 		void *buf, unsigned bufflen);
280 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
281 		struct nvme_completion *cqe, void *buffer, unsigned bufflen,
282 		unsigned timeout, int qid, int at_head, int flags);
283 int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
284 		void __user *ubuffer, unsigned bufflen, u32 *result,
285 		unsigned timeout);
286 int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
287 		void __user *ubuffer, unsigned bufflen,
288 		void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
289 		u32 *result, unsigned timeout);
290 int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id);
291 int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
292 		struct nvme_id_ns **id);
293 int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log);
294 int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
295 			dma_addr_t dma_addr, u32 *result);
296 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
297 			dma_addr_t dma_addr, u32 *result);
298 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count);
299 void nvme_start_keep_alive(struct nvme_ctrl *ctrl);
300 void nvme_stop_keep_alive(struct nvme_ctrl *ctrl);
301 
302 struct sg_io_hdr;
303 
304 int nvme_sg_io(struct nvme_ns *ns, struct sg_io_hdr __user *u_hdr);
305 int nvme_sg_io32(struct nvme_ns *ns, unsigned long arg);
306 int nvme_sg_get_version_num(int __user *ip);
307 
308 #ifdef CONFIG_NVM
309 int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id);
310 int nvme_nvm_register(struct request_queue *q, char *disk_name);
311 void nvme_nvm_unregister(struct request_queue *q, char *disk_name);
312 #else
313 static inline int nvme_nvm_register(struct request_queue *q, char *disk_name)
314 {
315 	return 0;
316 }
317 
318 static inline void nvme_nvm_unregister(struct request_queue *q, char *disk_name) {};
319 
320 static inline int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
321 {
322 	return 0;
323 }
324 #endif /* CONFIG_NVM */
325 
326 int __init nvme_core_init(void);
327 void nvme_core_exit(void);
328 
329 #endif /* _NVME_H */
330