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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _SCSI_SCSI_CMND_H
#define _SCSI_SCSI_CMND_H
#include <linux/dma-mapping.h>
#include <linux/blkdev.h>
#include <linux/t10-pi.h>
#include <linux/list.h>
#include <linux/types.h>
#include <linux/timer.h>
#include <linux/scatterlist.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_request.h>
struct Scsi_Host;
struct scsi_driver;
/*
* MAX_COMMAND_SIZE is:
* The longest fixed-length SCSI CDB as per the SCSI standard.
* fixed-length means: commands that their size can be determined
* by their opcode and the CDB does not carry a length specifier, (unlike
* the VARIABLE_LENGTH_CMD(0x7f) command). This is actually not exactly
* true and the SCSI standard also defines extended commands and
* vendor specific commands that can be bigger than 16 bytes. The kernel
* will support these using the same infrastructure used for VARLEN CDB's.
* So in effect MAX_COMMAND_SIZE means the maximum size command scsi-ml
* supports without specifying a cmd_len by ULD's
*/
#define MAX_COMMAND_SIZE 16
#if (MAX_COMMAND_SIZE > BLK_MAX_CDB)
# error MAX_COMMAND_SIZE can not be bigger than BLK_MAX_CDB
#endif
struct scsi_data_buffer {
struct sg_table table;
unsigned length;
};
/* embedded in scsi_cmnd */
struct scsi_pointer {
char *ptr; /* data pointer */
int this_residual; /* left in this buffer */
struct scatterlist *buffer; /* which buffer */
int buffers_residual; /* how many buffers left */
dma_addr_t dma_handle;
volatile int Status;
volatile int Message;
volatile int have_data_in;
volatile int sent_command;
volatile int phase;
};
/* for scmd->flags */
#define SCMD_TAGGED (1 << 0)
#define SCMD_INITIALIZED (1 << 1)
#define SCMD_LAST (1 << 2)
/* flags preserved across unprep / reprep */
#define SCMD_PRESERVED_FLAGS (SCMD_INITIALIZED)
/* for scmd->state */
#define SCMD_STATE_COMPLETE 0
#define SCMD_STATE_INFLIGHT 1
struct scsi_cmnd {
struct scsi_request req;
struct scsi_device *device;
struct list_head eh_entry; /* entry for the host eh_abort_list/eh_cmd_q */
struct delayed_work abort_work;
struct rcu_head rcu;
int eh_eflags; /* Used by error handlr */
int budget_token;
/*
* This is set to jiffies as it was when the command was first
* allocated. It is used to time how long the command has
* been outstanding
*/
unsigned long jiffies_at_alloc;
int retries;
int allowed;
unsigned char prot_op;
unsigned char prot_type;
unsigned char prot_flags;
unsigned short cmd_len;
enum dma_data_direction sc_data_direction;
/* These elements define the operation we are about to perform */
unsigned char *cmnd;
/* These elements define the operation we ultimately want to perform */
struct scsi_data_buffer sdb;
struct scsi_data_buffer *prot_sdb;
unsigned underflow; /* Return error if less than
this amount is transferred */
unsigned transfersize; /* How much we are guaranteed to
transfer with each SCSI transfer
(ie, between disconnect /
reconnects. Probably == sector
size */
unsigned char *sense_buffer;
/* obtained by REQUEST SENSE when
* CHECK CONDITION is received on original
* command (auto-sense). Length must be
* SCSI_SENSE_BUFFERSIZE bytes. */
/* Low-level done function - can be used by low-level driver to point
* to completion function. Not used by mid/upper level code. */
void (*scsi_done) (struct scsi_cmnd *);
/*
* The following fields can be written to by the host specific code.
* Everything else should be left alone.
*/
struct scsi_pointer SCp; /* Scratchpad used by some host adapters */
unsigned char *host_scribble; /* The host adapter is allowed to
* call scsi_malloc and get some memory
* and hang it here. The host adapter
* is also expected to call scsi_free
* to release this memory. (The memory
* obtained by scsi_malloc is guaranteed
* to be at an address < 16Mb). */
int result; /* Status code from lower level driver */
int flags; /* Command flags */
unsigned long state; /* Command completion state */
unsigned int extra_len; /* length of alignment and padding */
};
/* Variant of blk_mq_rq_from_pdu() that verifies the type of its argument. */
static inline struct request *scsi_cmd_to_rq(struct scsi_cmnd *scmd)
{
return blk_mq_rq_from_pdu(scmd);
}
/*
* Return the driver private allocation behind the command.
* Only works if cmd_size is set in the host template.
*/
static inline void *scsi_cmd_priv(struct scsi_cmnd *cmd)
{
return cmd + 1;
}
/* make sure not to use it with passthrough commands */
static inline struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd)
{
struct request *rq = scsi_cmd_to_rq(cmd);
return *(struct scsi_driver **)rq->rq_disk->private_data;
}
extern void scsi_finish_command(struct scsi_cmnd *cmd);
extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count,
size_t *offset, size_t *len);
extern void scsi_kunmap_atomic_sg(void *virt);
blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd);
void scsi_free_sgtables(struct scsi_cmnd *cmd);
#ifdef CONFIG_SCSI_DMA
extern int scsi_dma_map(struct scsi_cmnd *cmd);
extern void scsi_dma_unmap(struct scsi_cmnd *cmd);
#else /* !CONFIG_SCSI_DMA */
static inline int scsi_dma_map(struct scsi_cmnd *cmd) { return -ENOSYS; }
static inline void scsi_dma_unmap(struct scsi_cmnd *cmd) { }
#endif /* !CONFIG_SCSI_DMA */
static inline unsigned scsi_sg_count(struct scsi_cmnd *cmd)
{
return cmd->sdb.table.nents;
}
static inline struct scatterlist *scsi_sglist(struct scsi_cmnd *cmd)
{
return cmd->sdb.table.sgl;
}
static inline unsigned scsi_bufflen(struct scsi_cmnd *cmd)
{
return cmd->sdb.length;
}
static inline void scsi_set_resid(struct scsi_cmnd *cmd, unsigned int resid)
{
cmd->req.resid_len = resid;
}
static inline unsigned int scsi_get_resid(struct scsi_cmnd *cmd)
{
return cmd->req.resid_len;
}
#define scsi_for_each_sg(cmd, sg, nseg, __i) \
for_each_sg(scsi_sglist(cmd), sg, nseg, __i)
static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd *cmd,
const void *buf, int buflen)
{
return sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
buf, buflen);
}
static inline int scsi_sg_copy_to_buffer(struct scsi_cmnd *cmd,
void *buf, int buflen)
{
return sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
buf, buflen);
}
static inline sector_t scsi_get_sector(struct scsi_cmnd *scmd)
{
return blk_rq_pos(scsi_cmd_to_rq(scmd));
}
static inline sector_t scsi_get_lba(struct scsi_cmnd *scmd)
{
unsigned int shift = ilog2(scmd->device->sector_size) - SECTOR_SHIFT;
return blk_rq_pos(scsi_cmd_to_rq(scmd)) >> shift;
}
static inline unsigned int scsi_logical_block_count(struct scsi_cmnd *scmd)
{
unsigned int shift = ilog2(scmd->device->sector_size) - SECTOR_SHIFT;
return blk_rq_bytes(scsi_cmd_to_rq(scmd)) >> shift;
}
/*
* The operations below are hints that tell the controller driver how
* to handle I/Os with DIF or similar types of protection information.
*/
enum scsi_prot_operations {
/* Normal I/O */
SCSI_PROT_NORMAL = 0,
/* OS-HBA: Protected, HBA-Target: Unprotected */
SCSI_PROT_READ_INSERT,
SCSI_PROT_WRITE_STRIP,
/* OS-HBA: Unprotected, HBA-Target: Protected */
SCSI_PROT_READ_STRIP,
SCSI_PROT_WRITE_INSERT,
/* OS-HBA: Protected, HBA-Target: Protected */
SCSI_PROT_READ_PASS,
SCSI_PROT_WRITE_PASS,
};
static inline void scsi_set_prot_op(struct scsi_cmnd *scmd, unsigned char op)
{
scmd->prot_op = op;
}
static inline unsigned char scsi_get_prot_op(struct scsi_cmnd *scmd)
{
return scmd->prot_op;
}
enum scsi_prot_flags {
SCSI_PROT_TRANSFER_PI = 1 << 0,
SCSI_PROT_GUARD_CHECK = 1 << 1,
SCSI_PROT_REF_CHECK = 1 << 2,
SCSI_PROT_REF_INCREMENT = 1 << 3,
SCSI_PROT_IP_CHECKSUM = 1 << 4,
};
/*
* The controller usually does not know anything about the target it
* is communicating with. However, when DIX is enabled the controller
* must be know target type so it can verify the protection
* information passed along with the I/O.
*/
enum scsi_prot_target_type {
SCSI_PROT_DIF_TYPE0 = 0,
SCSI_PROT_DIF_TYPE1,
SCSI_PROT_DIF_TYPE2,
SCSI_PROT_DIF_TYPE3,
};
static inline void scsi_set_prot_type(struct scsi_cmnd *scmd, unsigned char type)
{
scmd->prot_type = type;
}
static inline unsigned char scsi_get_prot_type(struct scsi_cmnd *scmd)
{
return scmd->prot_type;
}
static inline u32 scsi_prot_ref_tag(struct scsi_cmnd *scmd)
{
struct request *rq = blk_mq_rq_from_pdu(scmd);
return t10_pi_ref_tag(rq);
}
static inline unsigned int scsi_prot_interval(struct scsi_cmnd *scmd)
{
return scmd->device->sector_size;
}
static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd)
{
return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0;
}
static inline struct scatterlist *scsi_prot_sglist(struct scsi_cmnd *cmd)
{
return cmd->prot_sdb ? cmd->prot_sdb->table.sgl : NULL;
}
static inline struct scsi_data_buffer *scsi_prot(struct scsi_cmnd *cmd)
{
return cmd->prot_sdb;
}
#define scsi_for_each_prot_sg(cmd, sg, nseg, __i) \
for_each_sg(scsi_prot_sglist(cmd), sg, nseg, __i)
static inline void set_status_byte(struct scsi_cmnd *cmd, char status)
{
cmd->result = (cmd->result & 0xffffff00) | status;
}
static inline u8 get_status_byte(struct scsi_cmnd *cmd)
{
return cmd->result & 0xff;
}
static inline void set_host_byte(struct scsi_cmnd *cmd, char status)
{
cmd->result = (cmd->result & 0xff00ffff) | (status << 16);
}
static inline u8 get_host_byte(struct scsi_cmnd *cmd)
{
return (cmd->result >> 16) & 0xff;
}
/**
* scsi_msg_to_host_byte() - translate message byte
*
* Translate the SCSI parallel message byte to a matching
* host byte setting. A message of COMMAND_COMPLETE indicates
* a successful command execution, any other message indicate
* an error. As the messages themselves only have a meaning
* for the SCSI parallel protocol this function translates
* them into a matching host byte value for SCSI EH.
*/
static inline void scsi_msg_to_host_byte(struct scsi_cmnd *cmd, u8 msg)
{
switch (msg) {
case COMMAND_COMPLETE:
break;
case ABORT_TASK_SET:
set_host_byte(cmd, DID_ABORT);
break;
case TARGET_RESET:
set_host_byte(cmd, DID_RESET);
break;
default:
set_host_byte(cmd, DID_ERROR);
break;
}
}
static inline unsigned scsi_transfer_length(struct scsi_cmnd *scmd)
{
unsigned int xfer_len = scmd->sdb.length;
unsigned int prot_interval = scsi_prot_interval(scmd);
if (scmd->prot_flags & SCSI_PROT_TRANSFER_PI)
xfer_len += (xfer_len >> ilog2(prot_interval)) * 8;
return xfer_len;
}
extern void scsi_build_sense(struct scsi_cmnd *scmd, int desc,
u8 key, u8 asc, u8 ascq);
#endif /* _SCSI_SCSI_CMND_H */
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