xref: /openbmc/linux/drivers/nvme/host/nvme.h (revision e983940270f10fe8551baf0098be76ea478294a3)
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 /* The below value is the specific amount of delay needed before checking
83  * readiness in case of the PCI_DEVICE(0x1c58, 0x0003), which needs the
84  * NVME_QUIRK_DELAY_BEFORE_CHK_RDY quirk enabled. The value (in ms) was
85  * found empirically.
86  */
87 #define NVME_QUIRK_DELAY_AMOUNT		2000
88 
89 enum nvme_ctrl_state {
90 	NVME_CTRL_NEW,
91 	NVME_CTRL_LIVE,
92 	NVME_CTRL_RESETTING,
93 	NVME_CTRL_RECONNECTING,
94 	NVME_CTRL_DELETING,
95 	NVME_CTRL_DEAD,
96 };
97 
98 struct nvme_ctrl {
99 	enum nvme_ctrl_state state;
100 	spinlock_t lock;
101 	const struct nvme_ctrl_ops *ops;
102 	struct request_queue *admin_q;
103 	struct request_queue *connect_q;
104 	struct device *dev;
105 	struct kref kref;
106 	int instance;
107 	struct blk_mq_tag_set *tagset;
108 	struct list_head namespaces;
109 	struct mutex namespaces_mutex;
110 	struct device *device;	/* char device */
111 	struct list_head node;
112 	struct ida ns_ida;
113 
114 	char name[12];
115 	char serial[20];
116 	char model[40];
117 	char firmware_rev[8];
118 	u16 cntlid;
119 
120 	u32 ctrl_config;
121 
122 	u32 page_size;
123 	u32 max_hw_sectors;
124 	u32 stripe_size;
125 	u16 oncs;
126 	u16 vid;
127 	atomic_t abort_limit;
128 	u8 event_limit;
129 	u8 vwc;
130 	u32 vs;
131 	u32 sgls;
132 	u16 kas;
133 	unsigned int kato;
134 	bool subsystem;
135 	unsigned long quirks;
136 	struct work_struct scan_work;
137 	struct work_struct async_event_work;
138 	struct delayed_work ka_work;
139 
140 	/* Fabrics only */
141 	u16 sqsize;
142 	u32 ioccsz;
143 	u32 iorcsz;
144 	u16 icdoff;
145 	u16 maxcmd;
146 	struct nvmf_ctrl_options *opts;
147 };
148 
149 /*
150  * An NVM Express namespace is equivalent to a SCSI LUN
151  */
152 struct nvme_ns {
153 	struct list_head list;
154 
155 	struct nvme_ctrl *ctrl;
156 	struct request_queue *queue;
157 	struct gendisk *disk;
158 	struct nvm_dev *ndev;
159 	struct kref kref;
160 	int instance;
161 
162 	u8 eui[8];
163 	u8 uuid[16];
164 
165 	unsigned ns_id;
166 	int lba_shift;
167 	u16 ms;
168 	bool ext;
169 	u8 pi_type;
170 	unsigned long flags;
171 
172 #define NVME_NS_REMOVING 0
173 #define NVME_NS_DEAD     1
174 
175 	u64 mode_select_num_blocks;
176 	u32 mode_select_block_len;
177 };
178 
179 struct nvme_ctrl_ops {
180 	const char *name;
181 	struct module *module;
182 	bool is_fabrics;
183 	int (*reg_read32)(struct nvme_ctrl *ctrl, u32 off, u32 *val);
184 	int (*reg_write32)(struct nvme_ctrl *ctrl, u32 off, u32 val);
185 	int (*reg_read64)(struct nvme_ctrl *ctrl, u32 off, u64 *val);
186 	int (*reset_ctrl)(struct nvme_ctrl *ctrl);
187 	void (*free_ctrl)(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 		      void *buffer, size_t buflen, u32 *result);
296 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
297 		      void *buffer, size_t buflen, 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 nvme_ns *ns, char *disk_name, int node,
311 		      const struct attribute_group *attrs);
312 void nvme_nvm_unregister(struct nvme_ns *ns);
313 
314 static inline struct nvme_ns *nvme_get_ns_from_dev(struct device *dev)
315 {
316 	if (dev->type->devnode)
317 		return dev_to_disk(dev)->private_data;
318 
319 	return (container_of(dev, struct nvm_dev, dev))->private_data;
320 }
321 #else
322 static inline int nvme_nvm_register(struct nvme_ns *ns, char *disk_name,
323 				    int node,
324 				    const struct attribute_group *attrs)
325 {
326 	return 0;
327 }
328 
329 static inline void nvme_nvm_unregister(struct nvme_ns *ns) {};
330 
331 static inline int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
332 {
333 	return 0;
334 }
335 static inline struct nvme_ns *nvme_get_ns_from_dev(struct device *dev)
336 {
337 	return dev_to_disk(dev)->private_data;
338 }
339 #endif /* CONFIG_NVM */
340 
341 int __init nvme_core_init(void);
342 void nvme_core_exit(void);
343 
344 #endif /* _NVME_H */
345