1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef TARGET_CORE_BACKEND_H
3 #define TARGET_CORE_BACKEND_H
4 
5 #include <linux/types.h>
6 #include <asm/unaligned.h>
7 #include <target/target_core_base.h>
8 
9 #define TRANSPORT_FLAG_PASSTHROUGH		0x1
10 /*
11  * ALUA commands, state checks and setup operations are handled by the
12  * backend module.
13  */
14 #define TRANSPORT_FLAG_PASSTHROUGH_ALUA		0x2
15 #define TRANSPORT_FLAG_PASSTHROUGH_PGR          0x4
16 
17 struct request_queue;
18 struct scatterlist;
19 
20 struct target_backend_ops {
21 	char name[16];
22 	char inquiry_prod[16];
23 	char inquiry_rev[4];
24 	struct module *owner;
25 
26 	u8 transport_flags;
27 
28 	int (*attach_hba)(struct se_hba *, u32);
29 	void (*detach_hba)(struct se_hba *);
30 	int (*pmode_enable_hba)(struct se_hba *, unsigned long);
31 
32 	struct se_device *(*alloc_device)(struct se_hba *, const char *);
33 	int (*configure_device)(struct se_device *);
34 	void (*destroy_device)(struct se_device *);
35 	void (*free_device)(struct se_device *device);
36 
37 	ssize_t (*set_configfs_dev_params)(struct se_device *,
38 					   const char *, ssize_t);
39 	ssize_t (*show_configfs_dev_params)(struct se_device *, char *);
40 
41 	sense_reason_t (*parse_cdb)(struct se_cmd *cmd);
42 	u32 (*get_device_type)(struct se_device *);
43 	sector_t (*get_blocks)(struct se_device *);
44 	sector_t (*get_alignment_offset_lbas)(struct se_device *);
45 	/* lbppbe = logical blocks per physical block exponent. see SBC-3 */
46 	unsigned int (*get_lbppbe)(struct se_device *);
47 	unsigned int (*get_io_min)(struct se_device *);
48 	unsigned int (*get_io_opt)(struct se_device *);
49 	unsigned char *(*get_sense_buffer)(struct se_cmd *);
50 	bool (*get_write_cache)(struct se_device *);
51 	int (*init_prot)(struct se_device *);
52 	int (*format_prot)(struct se_device *);
53 	void (*free_prot)(struct se_device *);
54 
55 	struct configfs_attribute **tb_dev_attrib_attrs;
56 	struct configfs_attribute **tb_dev_action_attrs;
57 };
58 
59 struct sbc_ops {
60 	sense_reason_t (*execute_rw)(struct se_cmd *cmd, struct scatterlist *,
61 				     u32, enum dma_data_direction);
62 	sense_reason_t (*execute_sync_cache)(struct se_cmd *cmd);
63 	sense_reason_t (*execute_write_same)(struct se_cmd *cmd);
64 	sense_reason_t (*execute_unmap)(struct se_cmd *cmd,
65 				sector_t lba, sector_t nolb);
66 };
67 
68 int	transport_backend_register(const struct target_backend_ops *);
69 void	target_backend_unregister(const struct target_backend_ops *);
70 
71 void	target_complete_cmd(struct se_cmd *, u8);
72 void	target_complete_cmd_with_length(struct se_cmd *, u8, int);
73 
74 void	transport_copy_sense_to_cmd(struct se_cmd *, unsigned char *);
75 
76 sense_reason_t	spc_parse_cdb(struct se_cmd *cmd, unsigned int *size);
77 sense_reason_t	spc_emulate_report_luns(struct se_cmd *cmd);
78 sense_reason_t	spc_emulate_inquiry_std(struct se_cmd *, unsigned char *);
79 sense_reason_t	spc_emulate_evpd_83(struct se_cmd *, unsigned char *);
80 
81 sense_reason_t	sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops);
82 u32	sbc_get_device_rev(struct se_device *dev);
83 u32	sbc_get_device_type(struct se_device *dev);
84 sector_t	sbc_get_write_same_sectors(struct se_cmd *cmd);
85 void	sbc_dif_generate(struct se_cmd *);
86 sense_reason_t	sbc_dif_verify(struct se_cmd *, sector_t, unsigned int,
87 				     unsigned int, struct scatterlist *, int);
88 void sbc_dif_copy_prot(struct se_cmd *, unsigned int, bool,
89 		       struct scatterlist *, int);
90 void	transport_set_vpd_proto_id(struct t10_vpd *, unsigned char *);
91 int	transport_set_vpd_assoc(struct t10_vpd *, unsigned char *);
92 int	transport_set_vpd_ident_type(struct t10_vpd *, unsigned char *);
93 int	transport_set_vpd_ident(struct t10_vpd *, unsigned char *);
94 
95 extern struct configfs_attribute *sbc_attrib_attrs[];
96 extern struct configfs_attribute *passthrough_attrib_attrs[];
97 
98 /* core helpers also used by command snooping in pscsi */
99 void	*transport_kmap_data_sg(struct se_cmd *);
100 void	transport_kunmap_data_sg(struct se_cmd *);
101 /* core helpers also used by xcopy during internal command setup */
102 sense_reason_t	transport_generic_map_mem_to_cmd(struct se_cmd *,
103 		struct scatterlist *, u32, struct scatterlist *, u32);
104 
105 bool	target_lun_is_rdonly(struct se_cmd *);
106 sense_reason_t passthrough_parse_cdb(struct se_cmd *cmd,
107 	sense_reason_t (*exec_cmd)(struct se_cmd *cmd));
108 
109 struct	se_device *target_find_device(int id, bool do_depend);
110 
111 bool target_sense_desc_format(struct se_device *dev);
112 sector_t target_to_linux_sector(struct se_device *dev, sector_t lb);
113 bool target_configure_unmap_from_queue(struct se_dev_attrib *attrib,
114 				       struct request_queue *q);
115 
116 
117 /* Only use get_unaligned_be24() if reading p - 1 is allowed. */
118 static inline uint32_t get_unaligned_be24(const uint8_t *const p)
119 {
120 	return get_unaligned_be32(p - 1) & 0xffffffU;
121 }
122 
123 #endif /* TARGET_CORE_BACKEND_H */
124