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Diffstat (limited to 'include/scsi/scsi_cmnd.h')
| -rw-r--r-- | include/scsi/scsi_cmnd.h | 320 |
1 files changed, 320 insertions, 0 deletions
diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h new file mode 100644 index 00000000..ac06cc59 --- /dev/null +++ b/include/scsi/scsi_cmnd.h @@ -0,0 +1,320 @@ +#ifndef _SCSI_SCSI_CMND_H +#define _SCSI_SCSI_CMND_H + +#include <linux/dma-mapping.h> +#include <linux/blkdev.h> +#include <linux/list.h> +#include <linux/types.h> +#include <linux/timer.h> +#include <linux/scatterlist.h> + +struct Scsi_Host; +struct scsi_device; +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; + int resid; +}; + +/* 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; +}; + +struct scsi_cmnd { + struct scsi_device *device; + struct list_head list; /* scsi_cmnd participates in queue lists */ + struct list_head eh_entry; /* entry for the host eh_cmd_q */ + int eh_eflags; /* Used by error handlr */ + + /* + * A SCSI Command is assigned a nonzero serial_number before passed + * to the driver's queue command function. The serial_number is + * cleared when scsi_done is entered indicating that the command + * has been completed. It is a bug for LLDDs to use this number + * for purposes other than printk (and even that is only useful + * for debugging). + */ + unsigned long serial_number; + + /* + * 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 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 */ + + struct request *request; /* The command we are + working on */ + +#define SCSI_SENSE_BUFFERSIZE 96 + unsigned char *sense_buffer; + /* obtained by REQUEST SENSE when + * CHECK CONDITION is received on original + * command (auto-sense) */ + + /* 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 */ + + unsigned char tag; /* SCSI-II queued command tag */ +}; + +static inline struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) +{ + struct scsi_driver **sdp; + + if (!cmd->request->rq_disk) + return NULL; + + sdp = (struct scsi_driver **)cmd->request->rq_disk->private_data; + if (!sdp) + return NULL; + + return *sdp; +} + +extern struct scsi_cmnd *scsi_get_command(struct scsi_device *, gfp_t); +extern struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *, gfp_t); +extern void scsi_put_command(struct scsi_cmnd *); +extern void __scsi_put_command(struct Scsi_Host *, struct scsi_cmnd *, + struct device *); +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); + +extern int scsi_init_io(struct scsi_cmnd *cmd, gfp_t gfp_mask); +extern void scsi_release_buffers(struct scsi_cmnd *cmd); + +extern int scsi_dma_map(struct scsi_cmnd *cmd); +extern void scsi_dma_unmap(struct scsi_cmnd *cmd); + +struct scsi_cmnd *scsi_allocate_command(gfp_t gfp_mask); +void scsi_free_command(gfp_t gfp_mask, struct scsi_cmnd *cmd); + +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, int resid) +{ + cmd->sdb.resid = resid; +} + +static inline int scsi_get_resid(struct scsi_cmnd *cmd) +{ + return cmd->sdb.resid; +} + +#define scsi_for_each_sg(cmd, sg, nseg, __i) \ + for_each_sg(scsi_sglist(cmd), sg, nseg, __i) + +static inline int scsi_bidi_cmnd(struct scsi_cmnd *cmd) +{ + return blk_bidi_rq(cmd->request) && + (cmd->request->next_rq->special != NULL); +} + +static inline struct scsi_data_buffer *scsi_in(struct scsi_cmnd *cmd) +{ + return scsi_bidi_cmnd(cmd) ? + cmd->request->next_rq->special : &cmd->sdb; +} + +static inline struct scsi_data_buffer *scsi_out(struct scsi_cmnd *cmd) +{ + return &cmd->sdb; +} + +static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd *cmd, + 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); +} + +/* + * 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; +} + +/* + * 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 sector_t scsi_get_lba(struct scsi_cmnd *scmd) +{ + return blk_rq_pos(scmd->request); +} + +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_msg_byte(struct scsi_cmnd *cmd, char status) +{ + cmd->result = (cmd->result & 0xffff00ff) | (status << 8); +} + +static inline void set_host_byte(struct scsi_cmnd *cmd, char status) +{ + cmd->result = (cmd->result & 0xff00ffff) | (status << 16); +} + +static inline void set_driver_byte(struct scsi_cmnd *cmd, char status) +{ + cmd->result = (cmd->result & 0x00ffffff) | (status << 24); +} + +#endif /* _SCSI_SCSI_CMND_H */ |