4135626a3d6f23007d4d479ee522b8efff6ea5ad
[linux-2.6-block.git] / drivers / nvme / host / nvme.h
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 };
76
77 struct nvme_ctrl {
78         enum nvme_ctrl_state state;
79         spinlock_t lock;
80         const struct nvme_ctrl_ops *ops;
81         struct request_queue *admin_q;
82         struct device *dev;
83         struct kref kref;
84         int instance;
85         struct blk_mq_tag_set *tagset;
86         struct list_head namespaces;
87         struct mutex namespaces_mutex;
88         struct device *device;  /* char device */
89         struct list_head node;
90         struct ida ns_ida;
91
92         char name[12];
93         char serial[20];
94         char model[40];
95         char firmware_rev[8];
96         u16 cntlid;
97
98         u32 ctrl_config;
99
100         u32 page_size;
101         u32 max_hw_sectors;
102         u32 stripe_size;
103         u16 oncs;
104         u16 vid;
105         atomic_t abort_limit;
106         u8 event_limit;
107         u8 vwc;
108         u32 vs;
109         bool subsystem;
110         unsigned long quirks;
111 };
112
113 /*
114  * An NVM Express namespace is equivalent to a SCSI LUN
115  */
116 struct nvme_ns {
117         struct list_head list;
118
119         struct nvme_ctrl *ctrl;
120         struct request_queue *queue;
121         struct gendisk *disk;
122         struct kref kref;
123         int instance;
124
125         u8 eui[8];
126         u8 uuid[16];
127
128         unsigned ns_id;
129         int lba_shift;
130         u16 ms;
131         bool ext;
132         u8 pi_type;
133         int type;
134         unsigned long flags;
135
136 #define NVME_NS_REMOVING 0
137 #define NVME_NS_DEAD     1
138
139         u64 mode_select_num_blocks;
140         u32 mode_select_block_len;
141 };
142
143 struct nvme_ctrl_ops {
144         struct module *module;
145         int (*reg_read32)(struct nvme_ctrl *ctrl, u32 off, u32 *val);
146         int (*reg_write32)(struct nvme_ctrl *ctrl, u32 off, u32 val);
147         int (*reg_read64)(struct nvme_ctrl *ctrl, u32 off, u64 *val);
148         int (*reset_ctrl)(struct nvme_ctrl *ctrl);
149         void (*free_ctrl)(struct nvme_ctrl *ctrl);
150 };
151
152 static inline bool nvme_ctrl_ready(struct nvme_ctrl *ctrl)
153 {
154         u32 val = 0;
155
156         if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &val))
157                 return false;
158         return val & NVME_CSTS_RDY;
159 }
160
161 static inline int nvme_reset_subsystem(struct nvme_ctrl *ctrl)
162 {
163         if (!ctrl->subsystem)
164                 return -ENOTTY;
165         return ctrl->ops->reg_write32(ctrl, NVME_REG_NSSR, 0x4E564D65);
166 }
167
168 static inline u64 nvme_block_nr(struct nvme_ns *ns, sector_t sector)
169 {
170         return (sector >> (ns->lba_shift - 9));
171 }
172
173 static inline unsigned nvme_map_len(struct request *rq)
174 {
175         if (rq->cmd_flags & REQ_DISCARD)
176                 return sizeof(struct nvme_dsm_range);
177         else
178                 return blk_rq_bytes(rq);
179 }
180
181 static inline int nvme_error_status(u16 status)
182 {
183         switch (status & 0x7ff) {
184         case NVME_SC_SUCCESS:
185                 return 0;
186         case NVME_SC_CAP_EXCEEDED:
187                 return -ENOSPC;
188         default:
189                 return -EIO;
190         }
191 }
192
193 static inline bool nvme_req_needs_retry(struct request *req, u16 status)
194 {
195         return !(status & NVME_SC_DNR || blk_noretry_request(req)) &&
196                 (jiffies - req->start_time) < req->timeout;
197 }
198
199 bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
200                 enum nvme_ctrl_state new_state);
201 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
202 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
203 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl);
204 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
205                 const struct nvme_ctrl_ops *ops, unsigned long quirks);
206 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl);
207 void nvme_put_ctrl(struct nvme_ctrl *ctrl);
208 int nvme_init_identify(struct nvme_ctrl *ctrl);
209
210 void nvme_scan_namespaces(struct nvme_ctrl *ctrl);
211 void nvme_remove_namespaces(struct nvme_ctrl *ctrl);
212
213 void nvme_stop_queues(struct nvme_ctrl *ctrl);
214 void nvme_start_queues(struct nvme_ctrl *ctrl);
215 void nvme_kill_queues(struct nvme_ctrl *ctrl);
216
217 struct request *nvme_alloc_request(struct request_queue *q,
218                 struct nvme_command *cmd, unsigned int flags);
219 void nvme_requeue_req(struct request *req);
220 int nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
221                 struct nvme_command *cmd);
222 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
223                 void *buf, unsigned bufflen);
224 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
225                 struct nvme_completion *cqe, void *buffer, unsigned bufflen,
226                 unsigned timeout);
227 int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
228                 void __user *ubuffer, unsigned bufflen, u32 *result,
229                 unsigned timeout);
230 int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
231                 void __user *ubuffer, unsigned bufflen,
232                 void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
233                 u32 *result, unsigned timeout);
234 int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id);
235 int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
236                 struct nvme_id_ns **id);
237 int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log);
238 int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
239                         dma_addr_t dma_addr, u32 *result);
240 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
241                         dma_addr_t dma_addr, u32 *result);
242 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count);
243
244 struct sg_io_hdr;
245
246 int nvme_sg_io(struct nvme_ns *ns, struct sg_io_hdr __user *u_hdr);
247 int nvme_sg_io32(struct nvme_ns *ns, unsigned long arg);
248 int nvme_sg_get_version_num(int __user *ip);
249
250 #ifdef CONFIG_NVM
251 int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id);
252 int nvme_nvm_register(struct request_queue *q, char *disk_name);
253 void nvme_nvm_unregister(struct request_queue *q, char *disk_name);
254 #else
255 static inline int nvme_nvm_register(struct request_queue *q, char *disk_name)
256 {
257         return 0;
258 }
259
260 static inline void nvme_nvm_unregister(struct request_queue *q, char *disk_name) {};
261
262 static inline int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
263 {
264         return 0;
265 }
266 #endif /* CONFIG_NVM */
267
268 int __init nvme_core_init(void);
269 void nvme_core_exit(void);
270
271 #endif /* _NVME_H */