https://github.com/torvalds/linux
Tip revision: b562e44f507e863c6792946e4e1b1449fbbac85d authored by Linus Torvalds on 14 March 2016, 04:28:54 UTC
Linux 4.5
Linux 4.5
Tip revision: b562e44
sd.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 512-byte sectors */
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;
}
/*
* 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 */