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Diffstat (limited to 'include/scsi/scsi_cmnd.h')
| -rw-r--r-- | include/scsi/scsi_cmnd.h | 392 |
1 files changed, 392 insertions, 0 deletions
diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h new file mode 100644 index 000000000..7d3622db3 --- /dev/null +++ b/include/scsi/scsi_cmnd.h @@ -0,0 +1,392 @@ +/* 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> + +struct Scsi_Host; + +/* + * 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 + +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 + +enum scsi_cmnd_submitter { + SUBMITTED_BY_BLOCK_LAYER = 0, + SUBMITTED_BY_SCSI_ERROR_HANDLER = 1, + SUBMITTED_BY_SCSI_RESET_IOCTL = 2, +} __packed; + +struct scsi_cmnd { + 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; + enum scsi_cmnd_submitter submitter; + + unsigned short cmd_len; + enum dma_data_direction sc_data_direction; + + unsigned char cmnd[32]; /* SCSI CDB */ + + /* 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 resid_len; /* residual count */ + unsigned sense_len; + 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. */ + + int flags; /* Command flags */ + unsigned long state; /* Command completion state */ + + unsigned int extra_len; /* length of alignment and padding */ + + /* + * The fields below can be modified by the LLD but the fields above + * must not be modified. + */ + + 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 */ +}; + +/* 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; +} + +void scsi_done(struct scsi_cmnd *cmd); +void scsi_done_direct(struct scsi_cmnd *cmd); + +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->resid_len = resid; +} + +static inline unsigned int scsi_get_resid(struct scsi_cmnd *cmd) +{ + return cmd->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); + +struct request *scsi_alloc_request(struct request_queue *q, blk_opf_t opf, + blk_mq_req_flags_t flags); + +#endif /* _SCSI_SCSI_CMND_H */ |