drivers/scsi/sd.h - kernel/bruno - Git at Google

 #ifndef _SCSI_DISK_H
 #define _SCSI_DISK_H

 /*
  * More than enough for everybody ;)  The huge number of majors
  * is a leftover from 16bit dev_t days, we don't really need that
  * much numberspace.
  */
 #define SD_MAJORS	16

 /*
  * Time out in seconds for disks and Magneto-opticals (which are slower).
  */
 #define SD_TIMEOUT		(30 * HZ)
 #define SD_MOD_TIMEOUT		(75 * HZ)
 /*
  * Flush timeout is a multiplier over the standard device timeout which is
  * user modifiable via sysfs but initially set to SD_TIMEOUT
  */
 #define SD_FLUSH_TIMEOUT_MULTIPLIER	2
 #define SD_WRITE_SAME_TIMEOUT	(120 * HZ)

 /*
  * Number of allowed retries
  */
 #define SD_MAX_RETRIES		5
 #define SD_PASSTHROUGH_RETRIES	1
 #define SD_MAX_MEDIUM_TIMEOUTS	2

 /*
  * Size of the initial data buffer for mode and read capacity data
  */
 #define SD_BUF_SIZE		512

 /*
  * Number of sectors at the end of the device to avoid multi-sector
  * accesses to in the case of last_sector_bug
  */
 #define SD_LAST_BUGGY_SECTORS	8

 enum {
 	SD_EXT_CDB_SIZE = 32,	/* Extended CDB size */
 	SD_MEMPOOL_SIZE = 2,	/* CDB pool size */
 };

 enum {
 	SD_DEF_XFER_BLOCKS = 0xffff,
 	SD_MAX_XFER_BLOCKS = 0xffffffff,
 	SD_MAX_WS10_BLOCKS = 0xffff,
 	SD_MAX_WS16_BLOCKS = 0x7fffff,
 };

 enum {
 	SD_LBP_FULL = 0,	/* Full logical block provisioning */
 	SD_LBP_UNMAP,		/* Use UNMAP command */
 	SD_LBP_WS16,		/* Use WRITE SAME(16) with UNMAP bit */
 	SD_LBP_WS10,		/* Use WRITE SAME(10) with UNMAP bit */
 	SD_LBP_ZERO,		/* Use WRITE SAME(10) with zero payload */
 	SD_LBP_DISABLE,		/* Discard disabled due to failed cmd */
 };

 struct scsi_disk {
 	struct scsi_driver *driver;	/* always &sd_template */
 	struct scsi_device *device;
 	struct device	dev;
 	struct gendisk	*disk;
 	atomic_t	openers;
 	sector_t	capacity;	/* size in logical blocks */
 	u32		max_xfer_blocks;
 	u32		opt_xfer_blocks;
 	u32		max_ws_blocks;
 	u32		max_unmap_blocks;
 	u32		unmap_granularity;
 	u32		unmap_alignment;
 	u32		index;
 	unsigned int	physical_block_size;
 	unsigned int	max_medium_access_timeouts;
 	unsigned int	medium_access_timed_out;
 	u8		media_present;
 	u8		write_prot;
 	u8		protection_type;/* Data Integrity Field */
 	u8		provisioning_mode;
 	unsigned	ATO : 1;	/* state of disk ATO bit */
 	unsigned	cache_override : 1; /* temp override of WCE,RCD */
 	unsigned	WCE : 1;	/* state of disk WCE bit */
 	unsigned	RCD : 1;	/* state of disk RCD bit, unused */
 	unsigned	DPOFUA : 1;	/* state of disk DPOFUA bit */
 	unsigned	first_scan : 1;
 	unsigned	lbpme : 1;
 	unsigned	lbprz : 1;
 	unsigned	lbpu : 1;
 	unsigned	lbpws : 1;
 	unsigned	lbpws10 : 1;
 	unsigned	lbpvpd : 1;
 	unsigned	ws10 : 1;
 	unsigned	ws16 : 1;
 };
 #define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)

 static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
 {
 	return container_of(disk->private_data, struct scsi_disk, driver);
 }

 #define sd_printk(prefix, sdsk, fmt, a...)				\
         (sdsk)->disk ?							\
 	      sdev_prefix_printk(prefix, (sdsk)->device,		\
 				 (sdsk)->disk->disk_name, fmt, ##a) :	\
 	      sdev_printk(prefix, (sdsk)->device, fmt, ##a)

 #define sd_first_printk(prefix, sdsk, fmt, a...)			\
 	do {								\
 		if ((sdkp)->first_scan)					\
 			sd_printk(prefix, sdsk, fmt, ##a);		\
 	} while (0)

 static inline int scsi_medium_access_command(struct scsi_cmnd *scmd)
 {
 	switch (scmd->cmnd[0]) {
 	case READ_6:
 	case READ_10:
 	case READ_12:
 	case READ_16:
 	case SYNCHRONIZE_CACHE:
 	case VERIFY:
 	case VERIFY_12:
 	case VERIFY_16:
 	case WRITE_6:
 	case WRITE_10:
 	case WRITE_12:
 	case WRITE_16:
 	case WRITE_SAME:
 	case WRITE_SAME_16:
 	case UNMAP:
 		return 1;
 	case VARIABLE_LENGTH_CMD:
 		switch (scmd->cmnd[9]) {
 		case READ_32:
 		case VERIFY_32:
 		case WRITE_32:
 		case WRITE_SAME_32:
 			return 1;
 		}
 	}

 	return 0;
 }

 static inline sector_t logical_to_sectors(struct scsi_device *sdev, sector_t blocks)
 {
 	return blocks << (ilog2(sdev->sector_size) - 9);
 }

 static inline unsigned int logical_to_bytes(struct scsi_device *sdev, sector_t blocks)
 {
 	return blocks * sdev->sector_size;
 }

 /*
  * A DIF-capable target device can be formatted with different
  * protection schemes.  Currently 0 through 3 are defined:
  *
  * Type 0 is regular (unprotected) I/O
  *
  * Type 1 defines the contents of the guard and reference tags
  *
  * Type 2 defines the contents of the guard and reference tags and
  * uses 32-byte commands to seed the latter
  *
  * Type 3 defines the contents of the guard tag only
  */

 enum sd_dif_target_protection_types {
 	SD_DIF_TYPE0_PROTECTION = 0x0,
 	SD_DIF_TYPE1_PROTECTION = 0x1,
 	SD_DIF_TYPE2_PROTECTION = 0x2,
 	SD_DIF_TYPE3_PROTECTION = 0x3,
 };

 /*
  * Look up the DIX operation based on whether the command is read or
  * write and whether dix and dif are enabled.
  */
 static inline unsigned int sd_prot_op(bool write, bool dix, bool dif)
 {
 	/* Lookup table: bit 2 (write), bit 1 (dix), bit 0 (dif) */
 	const unsigned int ops[] = {	/* wrt dix dif */
 		SCSI_PROT_NORMAL,	/*  0	0   0  */
 		SCSI_PROT_READ_STRIP,	/*  0	0   1  */
 		SCSI_PROT_READ_INSERT,	/*  0	1   0  */
 		SCSI_PROT_READ_PASS,	/*  0	1   1  */
 		SCSI_PROT_NORMAL,	/*  1	0   0  */
 		SCSI_PROT_WRITE_INSERT, /*  1	0   1  */
 		SCSI_PROT_WRITE_STRIP,	/*  1	1   0  */
 		SCSI_PROT_WRITE_PASS,	/*  1	1   1  */
 	};

 	return ops[write << 2 | dix << 1 | dif];
 }

 /*
  * Returns a mask of the protection flags that are valid for a given DIX
  * operation.
  */
 static inline unsigned int sd_prot_flag_mask(unsigned int prot_op)
 {
 	const unsigned int flag_mask[] = {
 		[SCSI_PROT_NORMAL]		= 0,

 		[SCSI_PROT_READ_STRIP]		= SCSI_PROT_TRANSFER_PI |
 						  SCSI_PROT_GUARD_CHECK |
 						  SCSI_PROT_REF_CHECK |
 						  SCSI_PROT_REF_INCREMENT,

 		[SCSI_PROT_READ_INSERT]		= SCSI_PROT_REF_INCREMENT |
 						  SCSI_PROT_IP_CHECKSUM,

 		[SCSI_PROT_READ_PASS]		= SCSI_PROT_TRANSFER_PI |
 						  SCSI_PROT_GUARD_CHECK |
 						  SCSI_PROT_REF_CHECK |
 						  SCSI_PROT_REF_INCREMENT |
 						  SCSI_PROT_IP_CHECKSUM,

 		[SCSI_PROT_WRITE_INSERT]	= SCSI_PROT_TRANSFER_PI |
 						  SCSI_PROT_REF_INCREMENT,

 		[SCSI_PROT_WRITE_STRIP]		= SCSI_PROT_GUARD_CHECK |
 						  SCSI_PROT_REF_CHECK |
 						  SCSI_PROT_REF_INCREMENT |
 						  SCSI_PROT_IP_CHECKSUM,

 		[SCSI_PROT_WRITE_PASS]		= SCSI_PROT_TRANSFER_PI |
 						  SCSI_PROT_GUARD_CHECK |
 						  SCSI_PROT_REF_CHECK |
 						  SCSI_PROT_REF_INCREMENT |
 						  SCSI_PROT_IP_CHECKSUM,
 	};

 	return flag_mask[prot_op];
 }

 /*
  * Data Integrity Field tuple.
  */
 struct sd_dif_tuple {
        __be16 guard_tag;	/* Checksum */
        __be16 app_tag;		/* Opaque storage */
        __be32 ref_tag;		/* Target LBA or indirect LBA */
 };

 #ifdef CONFIG_BLK_DEV_INTEGRITY

 extern void sd_dif_config_host(struct scsi_disk *);
 extern void sd_dif_prepare(struct scsi_cmnd *scmd);
 extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);

 #else /* CONFIG_BLK_DEV_INTEGRITY */

 static inline void sd_dif_config_host(struct scsi_disk *disk)
 {
 }
 static inline int sd_dif_prepare(struct scsi_cmnd *scmd)
 {
 	return 0;
 }
 static inline void sd_dif_complete(struct scsi_cmnd *cmd, unsigned int a)
 {
 }

 #endif /* CONFIG_BLK_DEV_INTEGRITY */

 #endif /* _SCSI_DISK_H */
	#ifndef _SCSI_DISK_H
	#define _SCSI_DISK_H

	/*
	* More than enough for everybody ;) The huge number of majors
	* is a leftover from 16bit dev_t days, we don't really need that
	* much numberspace.
	*/
	#define SD_MAJORS 16

	/*
	* Time out in seconds for disks and Magneto-opticals (which are slower).
	*/
	#define SD_TIMEOUT (30 * HZ)
	#define SD_MOD_TIMEOUT (75 * HZ)
	/*
	* Flush timeout is a multiplier over the standard device timeout which is
	* user modifiable via sysfs but initially set to SD_TIMEOUT
	*/
	#define SD_FLUSH_TIMEOUT_MULTIPLIER 2
	#define SD_WRITE_SAME_TIMEOUT (120 * HZ)

	/*
	* Number of allowed retries
	*/
	#define SD_MAX_RETRIES 5
	#define SD_PASSTHROUGH_RETRIES 1
	#define SD_MAX_MEDIUM_TIMEOUTS 2

	/*
	* Size of the initial data buffer for mode and read capacity data
	*/
	#define SD_BUF_SIZE 512

	/*
	* Number of sectors at the end of the device to avoid multi-sector
	* accesses to in the case of last_sector_bug
	*/
	#define SD_LAST_BUGGY_SECTORS 8

	enum {
	SD_EXT_CDB_SIZE = 32, /* Extended CDB size */
	SD_MEMPOOL_SIZE = 2, /* CDB pool size */
	};

	enum {
	SD_DEF_XFER_BLOCKS = 0xffff,
	SD_MAX_XFER_BLOCKS = 0xffffffff,
	SD_MAX_WS10_BLOCKS = 0xffff,
	SD_MAX_WS16_BLOCKS = 0x7fffff,
	};

	enum {
	SD_LBP_FULL = 0, /* Full logical block provisioning */
	SD_LBP_UNMAP, /* Use UNMAP command */
	SD_LBP_WS16, /* Use WRITE SAME(16) with UNMAP bit */
	SD_LBP_WS10, /* Use WRITE SAME(10) with UNMAP bit */
	SD_LBP_ZERO, /* Use WRITE SAME(10) with zero payload */
	SD_LBP_DISABLE, /* Discard disabled due to failed cmd */
	};

	struct scsi_disk {
	struct scsi_driver driver; / always &sd_template */
	struct scsi_device *device;
	struct device dev;
	struct gendisk *disk;
	atomic_t openers;
	sector_t capacity; /* size in logical blocks */
	u32 max_xfer_blocks;
	u32 opt_xfer_blocks;
	u32 max_ws_blocks;
	u32 max_unmap_blocks;
	u32 unmap_granularity;
	u32 unmap_alignment;
	u32 index;
	unsigned int physical_block_size;
	unsigned int max_medium_access_timeouts;
	unsigned int medium_access_timed_out;
	u8 media_present;
	u8 write_prot;
	u8 protection_type;/* Data Integrity Field */
	u8 provisioning_mode;
	unsigned ATO : 1; /* state of disk ATO bit */
	unsigned cache_override : 1; /* temp override of WCE,RCD */
	unsigned WCE : 1; /* state of disk WCE bit */
	unsigned RCD : 1; /* state of disk RCD bit, unused */
	unsigned DPOFUA : 1; /* state of disk DPOFUA bit */
	unsigned first_scan : 1;
	unsigned lbpme : 1;
	unsigned lbprz : 1;
	unsigned lbpu : 1;
	unsigned lbpws : 1;
	unsigned lbpws10 : 1;
	unsigned lbpvpd : 1;
	unsigned ws10 : 1;
	unsigned ws16 : 1;
	};
	#define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)

	static inline struct scsi_disk scsi_disk(struct gendisk disk)
	{
	return container_of(disk->private_data, struct scsi_disk, driver);
	}

	#define sd_printk(prefix, sdsk, fmt, a...) \
	(sdsk)->disk ? \
	sdev_prefix_printk(prefix, (sdsk)->device, \
	(sdsk)->disk->disk_name, fmt, ##a) : \
	sdev_printk(prefix, (sdsk)->device, fmt, ##a)

	#define sd_first_printk(prefix, sdsk, fmt, a...) \
	do { \
	if ((sdkp)->first_scan) \
	sd_printk(prefix, sdsk, fmt, ##a); \
	} while (0)

	static inline int scsi_medium_access_command(struct scsi_cmnd *scmd)
	{
	switch (scmd->cmnd[0]) {
	case READ_6:
	case READ_10:
	case READ_12:
	case READ_16:
	case SYNCHRONIZE_CACHE:
	case VERIFY:
	case VERIFY_12:
	case VERIFY_16:
	case WRITE_6:
	case WRITE_10:
	case WRITE_12:
	case WRITE_16:
	case WRITE_SAME:
	case WRITE_SAME_16:
	case UNMAP:
	return 1;
	case VARIABLE_LENGTH_CMD:
	switch (scmd->cmnd[9]) {
	case READ_32:
	case VERIFY_32:
	case WRITE_32:
	case WRITE_SAME_32:
	return 1;
	}
	}

	return 0;
	}

	static inline sector_t logical_to_sectors(struct scsi_device *sdev, sector_t blocks)
	{
	return blocks << (ilog2(sdev->sector_size) - 9);
	}

	static inline unsigned int logical_to_bytes(struct scsi_device *sdev, sector_t blocks)
	{
	return blocks * sdev->sector_size;
	}

	/*
	* A DIF-capable target device can be formatted with different
	* protection schemes. Currently 0 through 3 are defined:
	*
	* Type 0 is regular (unprotected) I/O
	*
	* Type 1 defines the contents of the guard and reference tags
	*
	* Type 2 defines the contents of the guard and reference tags and
	* uses 32-byte commands to seed the latter
	*
	* Type 3 defines the contents of the guard tag only
	*/

	enum sd_dif_target_protection_types {
	SD_DIF_TYPE0_PROTECTION = 0x0,
	SD_DIF_TYPE1_PROTECTION = 0x1,
	SD_DIF_TYPE2_PROTECTION = 0x2,
	SD_DIF_TYPE3_PROTECTION = 0x3,
	};

	/*
	* Look up the DIX operation based on whether the command is read or
	* write and whether dix and dif are enabled.
	*/
	static inline unsigned int sd_prot_op(bool write, bool dix, bool dif)
	{
	/* Lookup table: bit 2 (write), bit 1 (dix), bit 0 (dif) */
	const unsigned int ops[] = { /* wrt dix dif */
	SCSI_PROT_NORMAL, /* 0 0 0 */
	SCSI_PROT_READ_STRIP, /* 0 0 1 */
	SCSI_PROT_READ_INSERT, /* 0 1 0 */
	SCSI_PROT_READ_PASS, /* 0 1 1 */
	SCSI_PROT_NORMAL, /* 1 0 0 */
	SCSI_PROT_WRITE_INSERT, /* 1 0 1 */
	SCSI_PROT_WRITE_STRIP, /* 1 1 0 */
	SCSI_PROT_WRITE_PASS, /* 1 1 1 */
	};

	return ops[write << 2 \| dix << 1 \| dif];
	}

	/*
	* Returns a mask of the protection flags that are valid for a given DIX
	* operation.
	*/
	static inline unsigned int sd_prot_flag_mask(unsigned int prot_op)
	{
	const unsigned int flag_mask[] = {
	[SCSI_PROT_NORMAL] = 0,

	[SCSI_PROT_READ_STRIP] = SCSI_PROT_TRANSFER_PI \|
	SCSI_PROT_GUARD_CHECK \|
	SCSI_PROT_REF_CHECK \|
	SCSI_PROT_REF_INCREMENT,

	[SCSI_PROT_READ_INSERT] = SCSI_PROT_REF_INCREMENT \|
	SCSI_PROT_IP_CHECKSUM,

	[SCSI_PROT_READ_PASS] = SCSI_PROT_TRANSFER_PI \|
	SCSI_PROT_GUARD_CHECK \|
	SCSI_PROT_REF_CHECK \|
	SCSI_PROT_REF_INCREMENT \|
	SCSI_PROT_IP_CHECKSUM,

	[SCSI_PROT_WRITE_INSERT] = SCSI_PROT_TRANSFER_PI \|
	SCSI_PROT_REF_INCREMENT,

	[SCSI_PROT_WRITE_STRIP] = SCSI_PROT_GUARD_CHECK \|
	SCSI_PROT_REF_CHECK \|
	SCSI_PROT_REF_INCREMENT \|
	SCSI_PROT_IP_CHECKSUM,

	[SCSI_PROT_WRITE_PASS] = SCSI_PROT_TRANSFER_PI \|
	SCSI_PROT_GUARD_CHECK \|
	SCSI_PROT_REF_CHECK \|
	SCSI_PROT_REF_INCREMENT \|
	SCSI_PROT_IP_CHECKSUM,
	};

	return flag_mask[prot_op];
	}

	/*
	* Data Integrity Field tuple.
	*/
	struct sd_dif_tuple {
	__be16 guard_tag; /* Checksum */
	__be16 app_tag; /* Opaque storage */
	__be32 ref_tag; /* Target LBA or indirect LBA */
	};

	#ifdef CONFIG_BLK_DEV_INTEGRITY

	extern void sd_dif_config_host(struct scsi_disk *);
	extern void sd_dif_prepare(struct scsi_cmnd *scmd);
	extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);

	#else /* CONFIG_BLK_DEV_INTEGRITY */

	static inline void sd_dif_config_host(struct scsi_disk *disk)
	{
	}
	static inline int sd_dif_prepare(struct scsi_cmnd *scmd)
	{
	return 0;
	}
	static inline void sd_dif_complete(struct scsi_cmnd *cmd, unsigned int a)
	{
	}

	#endif /* CONFIG_BLK_DEV_INTEGRITY */

	#endif /* _SCSI_DISK_H */