xref: /openbmc/linux/drivers/nvme/host/nvme.h (revision ae3473231e77a3f1909d48cd144cebe5e1d049b3)
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 #include <linux/lightnvm.h>
22 
23 enum {
24 	/*
25 	 * Driver internal status code for commands that were cancelled due
26 	 * to timeouts or controller shutdown.  The value is negative so
27 	 * that it a) doesn't overlap with the unsigned hardware error codes,
28 	 * and b) can easily be tested for.
29 	 */
30 	NVME_SC_CANCELLED		= -EINTR,
31 };
32 
33 extern unsigned char nvme_io_timeout;
34 #define NVME_IO_TIMEOUT	(nvme_io_timeout * HZ)
35 
36 extern unsigned char admin_timeout;
37 #define ADMIN_TIMEOUT	(admin_timeout * HZ)
38 
39 extern unsigned char shutdown_timeout;
40 #define SHUTDOWN_TIMEOUT	(shutdown_timeout * HZ)
41 
42 #define NVME_DEFAULT_KATO	5
43 #define NVME_KATO_GRACE		10
44 
45 extern unsigned int nvme_max_retries;
46 
47 enum {
48 	NVME_NS_LBA		= 0,
49 	NVME_NS_LIGHTNVM	= 1,
50 };
51 
52 /*
53  * List of workarounds for devices that required behavior not specified in
54  * the standard.
55  */
56 enum nvme_quirks {
57 	/*
58 	 * Prefers I/O aligned to a stripe size specified in a vendor
59 	 * specific Identify field.
60 	 */
61 	NVME_QUIRK_STRIPE_SIZE			= (1 << 0),
62 
63 	/*
64 	 * The controller doesn't handle Identify value others than 0 or 1
65 	 * correctly.
66 	 */
67 	NVME_QUIRK_IDENTIFY_CNS			= (1 << 1),
68 
69 	/*
70 	 * The controller deterministically returns O's on reads to discarded
71 	 * logical blocks.
72 	 */
73 	NVME_QUIRK_DISCARD_ZEROES		= (1 << 2),
74 
75 	/*
76 	 * The controller needs a delay before starts checking the device
77 	 * readiness, which is done by reading the NVME_CSTS_RDY bit.
78 	 */
79 	NVME_QUIRK_DELAY_BEFORE_CHK_RDY		= (1 << 3),
80 };
81 
82 /*
83  * Common request structure for NVMe passthrough.  All drivers must have
84  * this structure as the first member of their request-private data.
85  */
86 struct nvme_request {
87 	struct nvme_command	*cmd;
88 	union nvme_result	result;
89 };
90 
91 static inline struct nvme_request *nvme_req(struct request *req)
92 {
93 	return blk_mq_rq_to_pdu(req);
94 }
95 
96 /* The below value is the specific amount of delay needed before checking
97  * readiness in case of the PCI_DEVICE(0x1c58, 0x0003), which needs the
98  * NVME_QUIRK_DELAY_BEFORE_CHK_RDY quirk enabled. The value (in ms) was
99  * found empirically.
100  */
101 #define NVME_QUIRK_DELAY_AMOUNT		2000
102 
103 enum nvme_ctrl_state {
104 	NVME_CTRL_NEW,
105 	NVME_CTRL_LIVE,
106 	NVME_CTRL_RESETTING,
107 	NVME_CTRL_RECONNECTING,
108 	NVME_CTRL_DELETING,
109 	NVME_CTRL_DEAD,
110 };
111 
112 struct nvme_ctrl {
113 	enum nvme_ctrl_state state;
114 	spinlock_t lock;
115 	const struct nvme_ctrl_ops *ops;
116 	struct request_queue *admin_q;
117 	struct request_queue *connect_q;
118 	struct device *dev;
119 	struct kref kref;
120 	int instance;
121 	struct blk_mq_tag_set *tagset;
122 	struct list_head namespaces;
123 	struct mutex namespaces_mutex;
124 	struct device *device;	/* char device */
125 	struct list_head node;
126 	struct ida ns_ida;
127 
128 	char name[12];
129 	char serial[20];
130 	char model[40];
131 	char firmware_rev[8];
132 	u16 cntlid;
133 
134 	u32 ctrl_config;
135 
136 	u32 page_size;
137 	u32 max_hw_sectors;
138 	u32 stripe_size;
139 	u16 oncs;
140 	u16 vid;
141 	atomic_t abort_limit;
142 	u8 event_limit;
143 	u8 vwc;
144 	u32 vs;
145 	u32 sgls;
146 	u16 kas;
147 	unsigned int kato;
148 	bool subsystem;
149 	unsigned long quirks;
150 	struct work_struct scan_work;
151 	struct work_struct async_event_work;
152 	struct delayed_work ka_work;
153 
154 	/* Fabrics only */
155 	u16 sqsize;
156 	u32 ioccsz;
157 	u32 iorcsz;
158 	u16 icdoff;
159 	u16 maxcmd;
160 	struct nvmf_ctrl_options *opts;
161 };
162 
163 /*
164  * An NVM Express namespace is equivalent to a SCSI LUN
165  */
166 struct nvme_ns {
167 	struct list_head list;
168 
169 	struct nvme_ctrl *ctrl;
170 	struct request_queue *queue;
171 	struct gendisk *disk;
172 	struct nvm_dev *ndev;
173 	struct kref kref;
174 	int instance;
175 
176 	u8 eui[8];
177 	u8 uuid[16];
178 
179 	unsigned ns_id;
180 	int lba_shift;
181 	u16 ms;
182 	bool ext;
183 	u8 pi_type;
184 	unsigned long flags;
185 
186 #define NVME_NS_REMOVING 0
187 #define NVME_NS_DEAD     1
188 
189 	u64 mode_select_num_blocks;
190 	u32 mode_select_block_len;
191 };
192 
193 struct nvme_ctrl_ops {
194 	const char *name;
195 	struct module *module;
196 	bool is_fabrics;
197 	int (*reg_read32)(struct nvme_ctrl *ctrl, u32 off, u32 *val);
198 	int (*reg_write32)(struct nvme_ctrl *ctrl, u32 off, u32 val);
199 	int (*reg_read64)(struct nvme_ctrl *ctrl, u32 off, u64 *val);
200 	int (*reset_ctrl)(struct nvme_ctrl *ctrl);
201 	void (*free_ctrl)(struct nvme_ctrl *ctrl);
202 	void (*submit_async_event)(struct nvme_ctrl *ctrl, int aer_idx);
203 	int (*delete_ctrl)(struct nvme_ctrl *ctrl);
204 	const char *(*get_subsysnqn)(struct nvme_ctrl *ctrl);
205 	int (*get_address)(struct nvme_ctrl *ctrl, char *buf, int size);
206 };
207 
208 static inline bool nvme_ctrl_ready(struct nvme_ctrl *ctrl)
209 {
210 	u32 val = 0;
211 
212 	if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &val))
213 		return false;
214 	return val & NVME_CSTS_RDY;
215 }
216 
217 static inline int nvme_reset_subsystem(struct nvme_ctrl *ctrl)
218 {
219 	if (!ctrl->subsystem)
220 		return -ENOTTY;
221 	return ctrl->ops->reg_write32(ctrl, NVME_REG_NSSR, 0x4E564D65);
222 }
223 
224 static inline u64 nvme_block_nr(struct nvme_ns *ns, sector_t sector)
225 {
226 	return (sector >> (ns->lba_shift - 9));
227 }
228 
229 static inline unsigned nvme_map_len(struct request *rq)
230 {
231 	if (req_op(rq) == REQ_OP_DISCARD)
232 		return sizeof(struct nvme_dsm_range);
233 	else
234 		return blk_rq_bytes(rq);
235 }
236 
237 static inline void nvme_cleanup_cmd(struct request *req)
238 {
239 	if (req->rq_flags & RQF_SPECIAL_PAYLOAD) {
240 		kfree(page_address(req->special_vec.bv_page) +
241 		      req->special_vec.bv_offset);
242 	}
243 }
244 
245 static inline int nvme_error_status(u16 status)
246 {
247 	switch (status & 0x7ff) {
248 	case NVME_SC_SUCCESS:
249 		return 0;
250 	case NVME_SC_CAP_EXCEEDED:
251 		return -ENOSPC;
252 	default:
253 		return -EIO;
254 	}
255 }
256 
257 static inline bool nvme_req_needs_retry(struct request *req, u16 status)
258 {
259 	return !(status & NVME_SC_DNR || blk_noretry_request(req)) &&
260 		(jiffies - req->start_time) < req->timeout &&
261 		req->retries < nvme_max_retries;
262 }
263 
264 void nvme_cancel_request(struct request *req, void *data, bool reserved);
265 bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
266 		enum nvme_ctrl_state new_state);
267 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
268 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
269 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl);
270 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
271 		const struct nvme_ctrl_ops *ops, unsigned long quirks);
272 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl);
273 void nvme_put_ctrl(struct nvme_ctrl *ctrl);
274 int nvme_init_identify(struct nvme_ctrl *ctrl);
275 
276 void nvme_queue_scan(struct nvme_ctrl *ctrl);
277 void nvme_remove_namespaces(struct nvme_ctrl *ctrl);
278 
279 #define NVME_NR_AERS	1
280 void nvme_complete_async_event(struct nvme_ctrl *ctrl, __le16 status,
281 		union nvme_result *res);
282 void nvme_queue_async_events(struct nvme_ctrl *ctrl);
283 
284 void nvme_stop_queues(struct nvme_ctrl *ctrl);
285 void nvme_start_queues(struct nvme_ctrl *ctrl);
286 void nvme_kill_queues(struct nvme_ctrl *ctrl);
287 
288 #define NVME_QID_ANY -1
289 struct request *nvme_alloc_request(struct request_queue *q,
290 		struct nvme_command *cmd, unsigned int flags, int qid);
291 void nvme_requeue_req(struct request *req);
292 int nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
293 		struct nvme_command *cmd);
294 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
295 		void *buf, unsigned bufflen);
296 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
297 		union nvme_result *result, void *buffer, unsigned bufflen,
298 		unsigned timeout, int qid, int at_head, int flags);
299 int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
300 		void __user *ubuffer, unsigned bufflen, u32 *result,
301 		unsigned timeout);
302 int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
303 		void __user *ubuffer, unsigned bufflen,
304 		void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
305 		u32 *result, unsigned timeout);
306 int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id);
307 int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
308 		struct nvme_id_ns **id);
309 int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log);
310 int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
311 		      void *buffer, size_t buflen, u32 *result);
312 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
313 		      void *buffer, size_t buflen, u32 *result);
314 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count);
315 void nvme_start_keep_alive(struct nvme_ctrl *ctrl);
316 void nvme_stop_keep_alive(struct nvme_ctrl *ctrl);
317 
318 struct sg_io_hdr;
319 
320 int nvme_sg_io(struct nvme_ns *ns, struct sg_io_hdr __user *u_hdr);
321 int nvme_sg_io32(struct nvme_ns *ns, unsigned long arg);
322 int nvme_sg_get_version_num(int __user *ip);
323 
324 #ifdef CONFIG_NVM
325 int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id);
326 int nvme_nvm_register(struct nvme_ns *ns, char *disk_name, int node);
327 void nvme_nvm_unregister(struct nvme_ns *ns);
328 int nvme_nvm_register_sysfs(struct nvme_ns *ns);
329 void nvme_nvm_unregister_sysfs(struct nvme_ns *ns);
330 #else
331 static inline int nvme_nvm_register(struct nvme_ns *ns, char *disk_name,
332 				    int node)
333 {
334 	return 0;
335 }
336 
337 static inline void nvme_nvm_unregister(struct nvme_ns *ns) {};
338 static inline int nvme_nvm_register_sysfs(struct nvme_ns *ns)
339 {
340 	return 0;
341 }
342 static inline void nvme_nvm_unregister_sysfs(struct nvme_ns *ns) {};
343 static inline int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
344 {
345 	return 0;
346 }
347 #endif /* CONFIG_NVM */
348 
349 static inline struct nvme_ns *nvme_get_ns_from_dev(struct device *dev)
350 {
351 	return dev_to_disk(dev)->private_data;
352 }
353 
354 int __init nvme_core_init(void);
355 void nvme_core_exit(void);
356 
357 #endif /* _NVME_H */
358