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
 17struct request_queue;
 18struct scatterlist;
 19
 20struct 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
 59struct 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
 68int	transport_backend_register(const struct target_backend_ops *);
 69void	target_backend_unregister(const struct target_backend_ops *);
 70
 71void	target_complete_cmd(struct se_cmd *, u8);
 72void	target_complete_cmd_with_length(struct se_cmd *, u8, int);
 73
 74void	transport_copy_sense_to_cmd(struct se_cmd *, unsigned char *);
 75
 76sense_reason_t	spc_parse_cdb(struct se_cmd *cmd, unsigned int *size);
 77sense_reason_t	spc_emulate_report_luns(struct se_cmd *cmd);
 78sense_reason_t	spc_emulate_inquiry_std(struct se_cmd *, unsigned char *);
 79sense_reason_t	spc_emulate_evpd_83(struct se_cmd *, unsigned char *);
 80
 81sense_reason_t	sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops);
 82u32	sbc_get_device_rev(struct se_device *dev);
 83u32	sbc_get_device_type(struct se_device *dev);
 84sector_t	sbc_get_write_same_sectors(struct se_cmd *cmd);
 85void	sbc_dif_generate(struct se_cmd *);
 86sense_reason_t	sbc_dif_verify(struct se_cmd *, sector_t, unsigned int,
 87				     unsigned int, struct scatterlist *, int);
 88void sbc_dif_copy_prot(struct se_cmd *, unsigned int, bool,
 89		       struct scatterlist *, int);
 90void	transport_set_vpd_proto_id(struct t10_vpd *, unsigned char *);
 91int	transport_set_vpd_assoc(struct t10_vpd *, unsigned char *);
 92int	transport_set_vpd_ident_type(struct t10_vpd *, unsigned char *);
 93int	transport_set_vpd_ident(struct t10_vpd *, unsigned char *);
 94
 95extern struct configfs_attribute *sbc_attrib_attrs[];
 96extern struct configfs_attribute *passthrough_attrib_attrs[];
 97
 98/* core helpers also used by command snooping in pscsi */
 99void	*transport_kmap_data_sg(struct se_cmd *);
100void	transport_kunmap_data_sg(struct se_cmd *);
101/* core helpers also used by xcopy during internal command setup */
102sense_reason_t	transport_generic_map_mem_to_cmd(struct se_cmd *,
103		struct scatterlist *, u32, struct scatterlist *, u32);
104
105bool	target_lun_is_rdonly(struct se_cmd *);
106sense_reason_t passthrough_parse_cdb(struct se_cmd *cmd,
107	sense_reason_t (*exec_cmd)(struct se_cmd *cmd));
108
109struct	se_device *target_find_device(int id, bool do_depend);
110
111bool target_sense_desc_format(struct se_device *dev);
112sector_t target_to_linux_sector(struct se_device *dev, sector_t lb);
113bool 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. */
118static 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 */