brintos

brintos / linux-shallow public Read only

0
0
Text · 10.5 KiB · 8ecfb94 Raw
401 lines · c
1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _SCSI_SCSI_CMND_H3#define _SCSI_SCSI_CMND_H4 5#include <linux/dma-mapping.h>6#include <linux/blkdev.h>7#include <linux/t10-pi.h>8#include <linux/list.h>9#include <linux/types.h>10#include <linux/timer.h>11#include <linux/scatterlist.h>12#include <scsi/scsi_device.h>13 14struct Scsi_Host;15 16/*17 * MAX_COMMAND_SIZE is:18 * The longest fixed-length SCSI CDB as per the SCSI standard.19 * fixed-length means: commands that their size can be determined20 * by their opcode and the CDB does not carry a length specifier, (unlike21 * the VARIABLE_LENGTH_CMD(0x7f) command). This is actually not exactly22 * true and the SCSI standard also defines extended commands and23 * vendor specific commands that can be bigger than 16 bytes. The kernel24 * will support these using the same infrastructure used for VARLEN CDB's.25 * So in effect MAX_COMMAND_SIZE means the maximum size command scsi-ml26 * supports without specifying a cmd_len by ULD's27 */28#define MAX_COMMAND_SIZE 1629 30struct scsi_data_buffer {31	struct sg_table table;32	unsigned length;33};34 35/* embedded in scsi_cmnd */36struct scsi_pointer {37	char *ptr;		/* data pointer */38	int this_residual;	/* left in this buffer */39	struct scatterlist *buffer;	/* which buffer */40	int buffers_residual;	/* how many buffers left */41 42        dma_addr_t dma_handle;43 44	volatile int Status;45	volatile int Message;46	volatile int have_data_in;47	volatile int sent_command;48	volatile int phase;49};50 51/* for scmd->flags */52#define SCMD_TAGGED		(1 << 0)53#define SCMD_INITIALIZED	(1 << 1)54#define SCMD_LAST		(1 << 2)55/*56 * libata uses SCSI EH to fetch sense data for successful commands.57 * SCSI EH should not overwrite scmd->result when SCMD_FORCE_EH_SUCCESS is set.58 */59#define SCMD_FORCE_EH_SUCCESS	(1 << 3)60#define SCMD_FAIL_IF_RECOVERING	(1 << 4)61/* flags preserved across unprep / reprep */62#define SCMD_PRESERVED_FLAGS	(SCMD_INITIALIZED | SCMD_FAIL_IF_RECOVERING)63 64/* for scmd->state */65#define SCMD_STATE_COMPLETE	066#define SCMD_STATE_INFLIGHT	167 68enum scsi_cmnd_submitter {69	SUBMITTED_BY_BLOCK_LAYER = 0,70	SUBMITTED_BY_SCSI_ERROR_HANDLER = 1,71	SUBMITTED_BY_SCSI_RESET_IOCTL = 2,72} __packed;73 74struct scsi_cmnd {75	struct scsi_device *device;76	struct list_head eh_entry; /* entry for the host eh_abort_list/eh_cmd_q */77	struct delayed_work abort_work;78 79	struct rcu_head rcu;80 81	int eh_eflags;		/* Used by error handlr */82 83	int budget_token;84 85	/*86	 * This is set to jiffies as it was when the command was first87	 * allocated.  It is used to time how long the command has88	 * been outstanding89	 */90	unsigned long jiffies_at_alloc;91 92	int retries;93	int allowed;94 95	unsigned char prot_op;96	unsigned char prot_type;97	unsigned char prot_flags;98	enum scsi_cmnd_submitter submitter;99 100	unsigned short cmd_len;101	enum dma_data_direction sc_data_direction;102 103	unsigned char cmnd[32]; /* SCSI CDB */104 105	/* These elements define the operation we ultimately want to perform */106	struct scsi_data_buffer sdb;107	struct scsi_data_buffer *prot_sdb;108 109	unsigned underflow;	/* Return error if less than110				   this amount is transferred */111 112	unsigned transfersize;	/* How much we are guaranteed to113				   transfer with each SCSI transfer114				   (ie, between disconnect / 115				   reconnects.   Probably == sector116				   size */117	unsigned resid_len;	/* residual count */118	unsigned sense_len;119	unsigned char *sense_buffer;120				/* obtained by REQUEST SENSE when121				 * CHECK CONDITION is received on original122				 * command (auto-sense). Length must be123				 * SCSI_SENSE_BUFFERSIZE bytes. */124 125	int flags;		/* Command flags */126	unsigned long state;	/* Command completion state */127 128	unsigned int extra_len;	/* length of alignment and padding */129 130	/*131	 * The fields below can be modified by the LLD but the fields above132	 * must not be modified.133	 */134 135	unsigned char *host_scribble;	/* The host adapter is allowed to136					 * call scsi_malloc and get some memory137					 * and hang it here.  The host adapter138					 * is also expected to call scsi_free139					 * to release this memory.  (The memory140					 * obtained by scsi_malloc is guaranteed141					 * to be at an address < 16Mb). */142 143	int result;		/* Status code from lower level driver */144};145 146/* Variant of blk_mq_rq_from_pdu() that verifies the type of its argument. */147static inline struct request *scsi_cmd_to_rq(struct scsi_cmnd *scmd)148{149	return blk_mq_rq_from_pdu(scmd);150}151 152/*153 * Return the driver private allocation behind the command.154 * Only works if cmd_size is set in the host template.155 */156static inline void *scsi_cmd_priv(struct scsi_cmnd *cmd)157{158	return cmd + 1;159}160 161void scsi_done(struct scsi_cmnd *cmd);162void scsi_done_direct(struct scsi_cmnd *cmd);163 164extern void scsi_finish_command(struct scsi_cmnd *cmd);165 166extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count,167				 size_t *offset, size_t *len);168extern void scsi_kunmap_atomic_sg(void *virt);169 170blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd);171void scsi_free_sgtables(struct scsi_cmnd *cmd);172 173#ifdef CONFIG_SCSI_DMA174extern int scsi_dma_map(struct scsi_cmnd *cmd);175extern void scsi_dma_unmap(struct scsi_cmnd *cmd);176#else /* !CONFIG_SCSI_DMA */177static inline int scsi_dma_map(struct scsi_cmnd *cmd) { return -ENOSYS; }178static inline void scsi_dma_unmap(struct scsi_cmnd *cmd) { }179#endif /* !CONFIG_SCSI_DMA */180 181static inline unsigned scsi_sg_count(struct scsi_cmnd *cmd)182{183	return cmd->sdb.table.nents;184}185 186static inline struct scatterlist *scsi_sglist(struct scsi_cmnd *cmd)187{188	return cmd->sdb.table.sgl;189}190 191static inline unsigned scsi_bufflen(struct scsi_cmnd *cmd)192{193	return cmd->sdb.length;194}195 196static inline void scsi_set_resid(struct scsi_cmnd *cmd, unsigned int resid)197{198	cmd->resid_len = resid;199}200 201static inline unsigned int scsi_get_resid(struct scsi_cmnd *cmd)202{203	return cmd->resid_len;204}205 206#define scsi_for_each_sg(cmd, sg, nseg, __i)			\207	for_each_sg(scsi_sglist(cmd), sg, nseg, __i)208 209static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd *cmd,210					   const void *buf, int buflen)211{212	return sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),213				   buf, buflen);214}215 216static inline int scsi_sg_copy_to_buffer(struct scsi_cmnd *cmd,217					 void *buf, int buflen)218{219	return sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),220				 buf, buflen);221}222 223static inline sector_t scsi_get_sector(struct scsi_cmnd *scmd)224{225	return blk_rq_pos(scsi_cmd_to_rq(scmd));226}227 228static inline sector_t scsi_get_lba(struct scsi_cmnd *scmd)229{230	unsigned int shift = ilog2(scmd->device->sector_size) - SECTOR_SHIFT;231 232	return blk_rq_pos(scsi_cmd_to_rq(scmd)) >> shift;233}234 235static inline unsigned int scsi_logical_block_count(struct scsi_cmnd *scmd)236{237	unsigned int shift = ilog2(scmd->device->sector_size);238 239	return blk_rq_bytes(scsi_cmd_to_rq(scmd)) >> shift;240}241 242/*243 * The operations below are hints that tell the controller driver how244 * to handle I/Os with DIF or similar types of protection information.245 */246enum scsi_prot_operations {247	/* Normal I/O */248	SCSI_PROT_NORMAL = 0,249 250	/* OS-HBA: Protected, HBA-Target: Unprotected */251	SCSI_PROT_READ_INSERT,252	SCSI_PROT_WRITE_STRIP,253 254	/* OS-HBA: Unprotected, HBA-Target: Protected */255	SCSI_PROT_READ_STRIP,256	SCSI_PROT_WRITE_INSERT,257 258	/* OS-HBA: Protected, HBA-Target: Protected */259	SCSI_PROT_READ_PASS,260	SCSI_PROT_WRITE_PASS,261};262 263static inline void scsi_set_prot_op(struct scsi_cmnd *scmd, unsigned char op)264{265	scmd->prot_op = op;266}267 268static inline unsigned char scsi_get_prot_op(struct scsi_cmnd *scmd)269{270	return scmd->prot_op;271}272 273enum scsi_prot_flags {274	SCSI_PROT_TRANSFER_PI		= 1 << 0,275	SCSI_PROT_GUARD_CHECK		= 1 << 1,276	SCSI_PROT_REF_CHECK		= 1 << 2,277	SCSI_PROT_REF_INCREMENT		= 1 << 3,278	SCSI_PROT_IP_CHECKSUM		= 1 << 4,279};280 281/*282 * The controller usually does not know anything about the target it283 * is communicating with.  However, when DIX is enabled the controller284 * must be know target type so it can verify the protection285 * information passed along with the I/O.286 */287enum scsi_prot_target_type {288	SCSI_PROT_DIF_TYPE0 = 0,289	SCSI_PROT_DIF_TYPE1,290	SCSI_PROT_DIF_TYPE2,291	SCSI_PROT_DIF_TYPE3,292};293 294static inline void scsi_set_prot_type(struct scsi_cmnd *scmd, unsigned char type)295{296	scmd->prot_type = type;297}298 299static inline unsigned char scsi_get_prot_type(struct scsi_cmnd *scmd)300{301	return scmd->prot_type;302}303 304static inline u32 scsi_prot_ref_tag(struct scsi_cmnd *scmd)305{306	struct request *rq = blk_mq_rq_from_pdu(scmd);307 308	return t10_pi_ref_tag(rq);309}310 311static inline unsigned int scsi_prot_interval(struct scsi_cmnd *scmd)312{313	return scmd->device->sector_size;314}315 316static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd)317{318	return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0;319}320 321static inline struct scatterlist *scsi_prot_sglist(struct scsi_cmnd *cmd)322{323	return cmd->prot_sdb ? cmd->prot_sdb->table.sgl : NULL;324}325 326static inline struct scsi_data_buffer *scsi_prot(struct scsi_cmnd *cmd)327{328	return cmd->prot_sdb;329}330 331#define scsi_for_each_prot_sg(cmd, sg, nseg, __i)		\332	for_each_sg(scsi_prot_sglist(cmd), sg, nseg, __i)333 334static inline void set_status_byte(struct scsi_cmnd *cmd, char status)335{336	cmd->result = (cmd->result & 0xffffff00) | status;337}338 339static inline u8 get_status_byte(struct scsi_cmnd *cmd)340{341	return cmd->result & 0xff;342}343 344static inline void set_host_byte(struct scsi_cmnd *cmd, char status)345{346	cmd->result = (cmd->result & 0xff00ffff) | (status << 16);347}348 349static inline u8 get_host_byte(struct scsi_cmnd *cmd)350{351	return (cmd->result >> 16) & 0xff;352}353 354/**355 * scsi_msg_to_host_byte() - translate message byte356 * @cmd: the SCSI command357 * @msg: the SCSI parallel message byte to translate358 *359 * Translate the SCSI parallel message byte to a matching360 * host byte setting. A message of COMMAND_COMPLETE indicates361 * a successful command execution, any other message indicate362 * an error. As the messages themselves only have a meaning363 * for the SCSI parallel protocol this function translates364 * them into a matching host byte value for SCSI EH.365 */366static inline void scsi_msg_to_host_byte(struct scsi_cmnd *cmd, u8 msg)367{368	switch (msg) {369	case COMMAND_COMPLETE:370		break;371	case ABORT_TASK_SET:372		set_host_byte(cmd, DID_ABORT);373		break;374	case TARGET_RESET:375		set_host_byte(cmd, DID_RESET);376		break;377	default:378		set_host_byte(cmd, DID_ERROR);379		break;380	}381}382 383static inline unsigned scsi_transfer_length(struct scsi_cmnd *scmd)384{385	unsigned int xfer_len = scmd->sdb.length;386	unsigned int prot_interval = scsi_prot_interval(scmd);387 388	if (scmd->prot_flags & SCSI_PROT_TRANSFER_PI)389		xfer_len += (xfer_len >> ilog2(prot_interval)) * 8;390 391	return xfer_len;392}393 394extern void scsi_build_sense(struct scsi_cmnd *scmd, int desc,395			     u8 key, u8 asc, u8 ascq);396 397struct request *scsi_alloc_request(struct request_queue *q, blk_opf_t opf,398				   blk_mq_req_flags_t flags);399 400#endif /* _SCSI_SCSI_CMND_H */401