xref: /openbmc/linux/drivers/nvme/host/nvme.h (revision 56d06fa2)
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 struct nvme_ctrl {
71 	const struct nvme_ctrl_ops *ops;
72 	struct request_queue *admin_q;
73 	struct device *dev;
74 	struct kref kref;
75 	int instance;
76 	struct blk_mq_tag_set *tagset;
77 	struct list_head namespaces;
78 	struct mutex namespaces_mutex;
79 	struct device *device;	/* char device */
80 	struct list_head node;
81 	struct ida ns_ida;
82 
83 	char name[12];
84 	char serial[20];
85 	char model[40];
86 	char firmware_rev[8];
87 	int cntlid;
88 
89 	u32 ctrl_config;
90 
91 	u32 page_size;
92 	u32 max_hw_sectors;
93 	u32 stripe_size;
94 	u16 oncs;
95 	u16 vid;
96 	atomic_t abort_limit;
97 	u8 event_limit;
98 	u8 vwc;
99 	u32 vs;
100 	bool subsystem;
101 	unsigned long quirks;
102 };
103 
104 /*
105  * An NVM Express namespace is equivalent to a SCSI LUN
106  */
107 struct nvme_ns {
108 	struct list_head list;
109 
110 	struct nvme_ctrl *ctrl;
111 	struct request_queue *queue;
112 	struct gendisk *disk;
113 	struct kref kref;
114 	int instance;
115 
116 	u8 eui[8];
117 	u8 uuid[16];
118 
119 	unsigned ns_id;
120 	int lba_shift;
121 	u16 ms;
122 	bool ext;
123 	u8 pi_type;
124 	int type;
125 	unsigned long flags;
126 
127 #define NVME_NS_REMOVING 0
128 #define NVME_NS_DEAD     1
129 
130 	u64 mode_select_num_blocks;
131 	u32 mode_select_block_len;
132 };
133 
134 struct nvme_ctrl_ops {
135 	struct module *module;
136 	int (*reg_read32)(struct nvme_ctrl *ctrl, u32 off, u32 *val);
137 	int (*reg_write32)(struct nvme_ctrl *ctrl, u32 off, u32 val);
138 	int (*reg_read64)(struct nvme_ctrl *ctrl, u32 off, u64 *val);
139 	bool (*io_incapable)(struct nvme_ctrl *ctrl);
140 	int (*reset_ctrl)(struct nvme_ctrl *ctrl);
141 	void (*free_ctrl)(struct nvme_ctrl *ctrl);
142 };
143 
144 static inline bool nvme_ctrl_ready(struct nvme_ctrl *ctrl)
145 {
146 	u32 val = 0;
147 
148 	if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &val))
149 		return false;
150 	return val & NVME_CSTS_RDY;
151 }
152 
153 static inline bool nvme_io_incapable(struct nvme_ctrl *ctrl)
154 {
155 	u32 val = 0;
156 
157 	if (ctrl->ops->io_incapable(ctrl))
158 		return true;
159 	if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &val))
160 		return true;
161 	return val & NVME_CSTS_CFS;
162 }
163 
164 static inline int nvme_reset_subsystem(struct nvme_ctrl *ctrl)
165 {
166 	if (!ctrl->subsystem)
167 		return -ENOTTY;
168 	return ctrl->ops->reg_write32(ctrl, NVME_REG_NSSR, 0x4E564D65);
169 }
170 
171 static inline u64 nvme_block_nr(struct nvme_ns *ns, sector_t sector)
172 {
173 	return (sector >> (ns->lba_shift - 9));
174 }
175 
176 static inline void nvme_setup_flush(struct nvme_ns *ns,
177 		struct nvme_command *cmnd)
178 {
179 	memset(cmnd, 0, sizeof(*cmnd));
180 	cmnd->common.opcode = nvme_cmd_flush;
181 	cmnd->common.nsid = cpu_to_le32(ns->ns_id);
182 }
183 
184 static inline void nvme_setup_rw(struct nvme_ns *ns, struct request *req,
185 		struct nvme_command *cmnd)
186 {
187 	u16 control = 0;
188 	u32 dsmgmt = 0;
189 
190 	if (req->cmd_flags & REQ_FUA)
191 		control |= NVME_RW_FUA;
192 	if (req->cmd_flags & (REQ_FAILFAST_DEV | REQ_RAHEAD))
193 		control |= NVME_RW_LR;
194 
195 	if (req->cmd_flags & REQ_RAHEAD)
196 		dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
197 
198 	memset(cmnd, 0, sizeof(*cmnd));
199 	cmnd->rw.opcode = (rq_data_dir(req) ? nvme_cmd_write : nvme_cmd_read);
200 	cmnd->rw.command_id = req->tag;
201 	cmnd->rw.nsid = cpu_to_le32(ns->ns_id);
202 	cmnd->rw.slba = cpu_to_le64(nvme_block_nr(ns, blk_rq_pos(req)));
203 	cmnd->rw.length = cpu_to_le16((blk_rq_bytes(req) >> ns->lba_shift) - 1);
204 
205 	if (ns->ms) {
206 		switch (ns->pi_type) {
207 		case NVME_NS_DPS_PI_TYPE3:
208 			control |= NVME_RW_PRINFO_PRCHK_GUARD;
209 			break;
210 		case NVME_NS_DPS_PI_TYPE1:
211 		case NVME_NS_DPS_PI_TYPE2:
212 			control |= NVME_RW_PRINFO_PRCHK_GUARD |
213 					NVME_RW_PRINFO_PRCHK_REF;
214 			cmnd->rw.reftag = cpu_to_le32(
215 					nvme_block_nr(ns, blk_rq_pos(req)));
216 			break;
217 		}
218 		if (!blk_integrity_rq(req))
219 			control |= NVME_RW_PRINFO_PRACT;
220 	}
221 
222 	cmnd->rw.control = cpu_to_le16(control);
223 	cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
224 }
225 
226 
227 static inline int nvme_error_status(u16 status)
228 {
229 	switch (status & 0x7ff) {
230 	case NVME_SC_SUCCESS:
231 		return 0;
232 	case NVME_SC_CAP_EXCEEDED:
233 		return -ENOSPC;
234 	default:
235 		return -EIO;
236 	}
237 }
238 
239 static inline bool nvme_req_needs_retry(struct request *req, u16 status)
240 {
241 	return !(status & NVME_SC_DNR || blk_noretry_request(req)) &&
242 		(jiffies - req->start_time) < req->timeout;
243 }
244 
245 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
246 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
247 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl);
248 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
249 		const struct nvme_ctrl_ops *ops, unsigned long quirks);
250 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl);
251 void nvme_put_ctrl(struct nvme_ctrl *ctrl);
252 int nvme_init_identify(struct nvme_ctrl *ctrl);
253 
254 void nvme_scan_namespaces(struct nvme_ctrl *ctrl);
255 void nvme_remove_namespaces(struct nvme_ctrl *ctrl);
256 
257 void nvme_stop_queues(struct nvme_ctrl *ctrl);
258 void nvme_start_queues(struct nvme_ctrl *ctrl);
259 void nvme_kill_queues(struct nvme_ctrl *ctrl);
260 
261 struct request *nvme_alloc_request(struct request_queue *q,
262 		struct nvme_command *cmd, unsigned int flags);
263 void nvme_requeue_req(struct request *req);
264 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
265 		void *buf, unsigned bufflen);
266 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
267 		struct nvme_completion *cqe, void *buffer, unsigned bufflen,
268 		unsigned timeout);
269 int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
270 		void __user *ubuffer, unsigned bufflen, u32 *result,
271 		unsigned timeout);
272 int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
273 		void __user *ubuffer, unsigned bufflen,
274 		void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
275 		u32 *result, unsigned timeout);
276 int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id);
277 int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
278 		struct nvme_id_ns **id);
279 int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log);
280 int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
281 			dma_addr_t dma_addr, u32 *result);
282 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
283 			dma_addr_t dma_addr, u32 *result);
284 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count);
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