tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __BLK_NULL_BLK_H
3#define __BLK_NULL_BLK_H
4
5#undef pr_fmt
6#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7
8#include <linux/blkdev.h>
9#include <linux/slab.h>
10#include <linux/blk-mq.h>
11#include <linux/hrtimer.h>
12#include <linux/configfs.h>
13#include <linux/badblocks.h>
14#include <linux/fault-inject.h>
15#include <linux/spinlock.h>
16#include <linux/mutex.h>
17
18struct nullb_cmd {
19 struct request *rq;
20 struct bio *bio;
21 unsigned int tag;
22 blk_status_t error;
23 struct nullb_queue *nq;
24 struct hrtimer timer;
25 bool fake_timeout;
26};
27
28struct nullb_queue {
29 unsigned long *tag_map;
30 wait_queue_head_t wait;
31 unsigned int queue_depth;
32 struct nullb_device *dev;
33 unsigned int requeue_selection;
34
35 struct list_head poll_list;
36 spinlock_t poll_lock;
37
38 struct nullb_cmd *cmds;
39};
40
41struct nullb_zone {
42 /*
43 * Zone lock to prevent concurrent modification of a zone write
44 * pointer position and condition: with memory backing, a write
45 * command execution may sleep on memory allocation. For this case,
46 * use mutex as the zone lock. Otherwise, use the spinlock for
47 * locking the zone.
48 */
49 union {
50 spinlock_t spinlock;
51 struct mutex mutex;
52 };
53 enum blk_zone_type type;
54 enum blk_zone_cond cond;
55 sector_t start;
56 sector_t wp;
57 unsigned int len;
58 unsigned int capacity;
59};
60
61struct nullb_device {
62 struct nullb *nullb;
63 struct config_item item;
64 struct radix_tree_root data; /* data stored in the disk */
65 struct radix_tree_root cache; /* disk cache data */
66 unsigned long flags; /* device flags */
67 unsigned int curr_cache;
68 struct badblocks badblocks;
69
70 unsigned int nr_zones;
71 unsigned int nr_zones_imp_open;
72 unsigned int nr_zones_exp_open;
73 unsigned int nr_zones_closed;
74 unsigned int imp_close_zone_no;
75 struct nullb_zone *zones;
76 sector_t zone_size_sects;
77 bool need_zone_res_mgmt;
78 spinlock_t zone_res_lock;
79
80 unsigned long size; /* device size in MB */
81 unsigned long completion_nsec; /* time in ns to complete a request */
82 unsigned long cache_size; /* disk cache size in MB */
83 unsigned long zone_size; /* zone size in MB if device is zoned */
84 unsigned long zone_capacity; /* zone capacity in MB if device is zoned */
85 unsigned int zone_nr_conv; /* number of conventional zones */
86 unsigned int zone_max_open; /* max number of open zones */
87 unsigned int zone_max_active; /* max number of active zones */
88 unsigned int submit_queues; /* number of submission queues */
89 unsigned int prev_submit_queues; /* number of submission queues before change */
90 unsigned int poll_queues; /* number of IOPOLL submission queues */
91 unsigned int prev_poll_queues; /* number of IOPOLL submission queues before change */
92 unsigned int home_node; /* home node for the device */
93 unsigned int queue_mode; /* block interface */
94 unsigned int blocksize; /* block size */
95 unsigned int max_sectors; /* Max sectors per command */
96 unsigned int irqmode; /* IRQ completion handler */
97 unsigned int hw_queue_depth; /* queue depth */
98 unsigned int index; /* index of the disk, only valid with a disk */
99 unsigned int mbps; /* Bandwidth throttle cap (in MB/s) */
100 bool blocking; /* blocking blk-mq device */
101 bool use_per_node_hctx; /* use per-node allocation for hardware context */
102 bool power; /* power on/off the device */
103 bool memory_backed; /* if data is stored in memory */
104 bool discard; /* if support discard */
105 bool zoned; /* if device is zoned */
106 bool virt_boundary; /* virtual boundary on/off for the device */
107};
108
109struct nullb {
110 struct nullb_device *dev;
111 struct list_head list;
112 unsigned int index;
113 struct request_queue *q;
114 struct gendisk *disk;
115 struct blk_mq_tag_set *tag_set;
116 struct blk_mq_tag_set __tag_set;
117 unsigned int queue_depth;
118 atomic_long_t cur_bytes;
119 struct hrtimer bw_timer;
120 unsigned long cache_flush_pos;
121 spinlock_t lock;
122
123 struct nullb_queue *queues;
124 unsigned int nr_queues;
125 char disk_name[DISK_NAME_LEN];
126};
127
128blk_status_t null_handle_discard(struct nullb_device *dev, sector_t sector,
129 sector_t nr_sectors);
130blk_status_t null_process_cmd(struct nullb_cmd *cmd,
131 enum req_opf op, sector_t sector,
132 unsigned int nr_sectors);
133
134#ifdef CONFIG_BLK_DEV_ZONED
135int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q);
136int null_register_zoned_dev(struct nullb *nullb);
137void null_free_zoned_dev(struct nullb_device *dev);
138int null_report_zones(struct gendisk *disk, sector_t sector,
139 unsigned int nr_zones, report_zones_cb cb, void *data);
140blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd,
141 enum req_opf op, sector_t sector,
142 sector_t nr_sectors);
143size_t null_zone_valid_read_len(struct nullb *nullb,
144 sector_t sector, unsigned int len);
145#else
146static inline int null_init_zoned_dev(struct nullb_device *dev,
147 struct request_queue *q)
148{
149 pr_err("CONFIG_BLK_DEV_ZONED not enabled\n");
150 return -EINVAL;
151}
152static inline int null_register_zoned_dev(struct nullb *nullb)
153{
154 return -ENODEV;
155}
156static inline void null_free_zoned_dev(struct nullb_device *dev) {}
157static inline blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd,
158 enum req_opf op, sector_t sector, sector_t nr_sectors)
159{
160 return BLK_STS_NOTSUPP;
161}
162static inline size_t null_zone_valid_read_len(struct nullb *nullb,
163 sector_t sector,
164 unsigned int len)
165{
166 return len;
167}
168#define null_report_zones NULL
169#endif /* CONFIG_BLK_DEV_ZONED */
170#endif /* __NULL_BLK_H */