xref: /openbmc/linux/drivers/nvme/host/nvme.h (revision 3805e6a1)
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 enum {
42 	NVME_NS_LBA		= 0,
43 	NVME_NS_LIGHTNVM	= 1,
44 };
45 
46 /*
47  * List of workarounds for devices that required behavior not specified in
48  * the standard.
49  */
50 enum nvme_quirks {
51 	/*
52 	 * Prefers I/O aligned to a stripe size specified in a vendor
53 	 * specific Identify field.
54 	 */
55 	NVME_QUIRK_STRIPE_SIZE			= (1 << 0),
56 
57 	/*
58 	 * The controller doesn't handle Identify value others than 0 or 1
59 	 * correctly.
60 	 */
61 	NVME_QUIRK_IDENTIFY_CNS			= (1 << 1),
62 
63 	/*
64 	 * The controller deterministically returns O's on reads to discarded
65 	 * logical blocks.
66 	 */
67 	NVME_QUIRK_DISCARD_ZEROES		= (1 << 2),
68 };
69 
70 enum nvme_ctrl_state {
71 	NVME_CTRL_NEW,
72 	NVME_CTRL_LIVE,
73 	NVME_CTRL_RESETTING,
74 	NVME_CTRL_DELETING,
75 	NVME_CTRL_DEAD,
76 };
77 
78 struct nvme_ctrl {
79 	enum nvme_ctrl_state state;
80 	spinlock_t lock;
81 	const struct nvme_ctrl_ops *ops;
82 	struct request_queue *admin_q;
83 	struct device *dev;
84 	struct kref kref;
85 	int instance;
86 	struct blk_mq_tag_set *tagset;
87 	struct list_head namespaces;
88 	struct mutex namespaces_mutex;
89 	struct device *device;	/* char device */
90 	struct list_head node;
91 	struct ida ns_ida;
92 
93 	char name[12];
94 	char serial[20];
95 	char model[40];
96 	char firmware_rev[8];
97 	u16 cntlid;
98 
99 	u32 ctrl_config;
100 
101 	u32 page_size;
102 	u32 max_hw_sectors;
103 	u32 stripe_size;
104 	u16 oncs;
105 	u16 vid;
106 	atomic_t abort_limit;
107 	u8 event_limit;
108 	u8 vwc;
109 	u32 vs;
110 	bool subsystem;
111 	unsigned long quirks;
112 	struct work_struct scan_work;
113 	struct work_struct async_event_work;
114 };
115 
116 /*
117  * An NVM Express namespace is equivalent to a SCSI LUN
118  */
119 struct nvme_ns {
120 	struct list_head list;
121 
122 	struct nvme_ctrl *ctrl;
123 	struct request_queue *queue;
124 	struct gendisk *disk;
125 	struct kref kref;
126 	int instance;
127 
128 	u8 eui[8];
129 	u8 uuid[16];
130 
131 	unsigned ns_id;
132 	int lba_shift;
133 	u16 ms;
134 	bool ext;
135 	u8 pi_type;
136 	int type;
137 	unsigned long flags;
138 
139 #define NVME_NS_REMOVING 0
140 #define NVME_NS_DEAD     1
141 
142 	u64 mode_select_num_blocks;
143 	u32 mode_select_block_len;
144 };
145 
146 struct nvme_ctrl_ops {
147 	struct module *module;
148 	int (*reg_read32)(struct nvme_ctrl *ctrl, u32 off, u32 *val);
149 	int (*reg_write32)(struct nvme_ctrl *ctrl, u32 off, u32 val);
150 	int (*reg_read64)(struct nvme_ctrl *ctrl, u32 off, u64 *val);
151 	int (*reset_ctrl)(struct nvme_ctrl *ctrl);
152 	void (*free_ctrl)(struct nvme_ctrl *ctrl);
153 	void (*post_scan)(struct nvme_ctrl *ctrl);
154 	void (*submit_async_event)(struct nvme_ctrl *ctrl, int aer_idx);
155 };
156 
157 static inline bool nvme_ctrl_ready(struct nvme_ctrl *ctrl)
158 {
159 	u32 val = 0;
160 
161 	if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &val))
162 		return false;
163 	return val & NVME_CSTS_RDY;
164 }
165 
166 static inline int nvme_reset_subsystem(struct nvme_ctrl *ctrl)
167 {
168 	if (!ctrl->subsystem)
169 		return -ENOTTY;
170 	return ctrl->ops->reg_write32(ctrl, NVME_REG_NSSR, 0x4E564D65);
171 }
172 
173 static inline u64 nvme_block_nr(struct nvme_ns *ns, sector_t sector)
174 {
175 	return (sector >> (ns->lba_shift - 9));
176 }
177 
178 static inline unsigned nvme_map_len(struct request *rq)
179 {
180 	if (rq->cmd_flags & REQ_DISCARD)
181 		return sizeof(struct nvme_dsm_range);
182 	else
183 		return blk_rq_bytes(rq);
184 }
185 
186 static inline void nvme_cleanup_cmd(struct request *req)
187 {
188 	if (req->cmd_flags & REQ_DISCARD)
189 		kfree(req->completion_data);
190 }
191 
192 static inline int nvme_error_status(u16 status)
193 {
194 	switch (status & 0x7ff) {
195 	case NVME_SC_SUCCESS:
196 		return 0;
197 	case NVME_SC_CAP_EXCEEDED:
198 		return -ENOSPC;
199 	default:
200 		return -EIO;
201 	}
202 }
203 
204 static inline bool nvme_req_needs_retry(struct request *req, u16 status)
205 {
206 	return !(status & NVME_SC_DNR || blk_noretry_request(req)) &&
207 		(jiffies - req->start_time) < req->timeout;
208 }
209 
210 bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
211 		enum nvme_ctrl_state new_state);
212 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
213 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
214 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl);
215 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
216 		const struct nvme_ctrl_ops *ops, unsigned long quirks);
217 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl);
218 void nvme_put_ctrl(struct nvme_ctrl *ctrl);
219 int nvme_init_identify(struct nvme_ctrl *ctrl);
220 
221 void nvme_queue_scan(struct nvme_ctrl *ctrl);
222 void nvme_remove_namespaces(struct nvme_ctrl *ctrl);
223 
224 #define NVME_NR_AERS	1
225 void nvme_complete_async_event(struct nvme_ctrl *ctrl,
226 		struct nvme_completion *cqe);
227 void nvme_queue_async_events(struct nvme_ctrl *ctrl);
228 
229 void nvme_stop_queues(struct nvme_ctrl *ctrl);
230 void nvme_start_queues(struct nvme_ctrl *ctrl);
231 void nvme_kill_queues(struct nvme_ctrl *ctrl);
232 
233 struct request *nvme_alloc_request(struct request_queue *q,
234 		struct nvme_command *cmd, unsigned int flags);
235 void nvme_requeue_req(struct request *req);
236 int nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
237 		struct nvme_command *cmd);
238 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
239 		void *buf, unsigned bufflen);
240 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
241 		struct nvme_completion *cqe, void *buffer, unsigned bufflen,
242 		unsigned timeout);
243 int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
244 		void __user *ubuffer, unsigned bufflen, u32 *result,
245 		unsigned timeout);
246 int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
247 		void __user *ubuffer, unsigned bufflen,
248 		void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
249 		u32 *result, unsigned timeout);
250 int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id);
251 int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
252 		struct nvme_id_ns **id);
253 int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log);
254 int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
255 			dma_addr_t dma_addr, u32 *result);
256 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
257 			dma_addr_t dma_addr, u32 *result);
258 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count);
259 
260 struct sg_io_hdr;
261 
262 int nvme_sg_io(struct nvme_ns *ns, struct sg_io_hdr __user *u_hdr);
263 int nvme_sg_io32(struct nvme_ns *ns, unsigned long arg);
264 int nvme_sg_get_version_num(int __user *ip);
265 
266 #ifdef CONFIG_NVM
267 int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id);
268 int nvme_nvm_register(struct request_queue *q, char *disk_name);
269 void nvme_nvm_unregister(struct request_queue *q, char *disk_name);
270 #else
271 static inline int nvme_nvm_register(struct request_queue *q, char *disk_name)
272 {
273 	return 0;
274 }
275 
276 static inline void nvme_nvm_unregister(struct request_queue *q, char *disk_name) {};
277 
278 static inline int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
279 {
280 	return 0;
281 }
282 #endif /* CONFIG_NVM */
283 
284 int __init nvme_core_init(void);
285 void nvme_core_exit(void);
286 
287 #endif /* _NVME_H */
288