[SCSI] Host protection capabilities

Controllers that support protection information must indicate this to
the SCSI midlayer so that the ULD can prepare scsi_cmnds accordingly.

This patch implements a host mask and various types of protection:

 - DIF Type 1-3 (between HBA and disk)
 - DIX Type 0-3 (between OS and HBA)

The patch also allows the HBA to set the guard type to something
different than the T10-mandated CRC.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This commit is contained in:
Martin K. Petersen 2008-07-17 04:28:30 -04:00 committed by James Bottomley
parent 7c32c7a2d3
commit 4469f98780
2 changed files with 88 additions and 0 deletions

View file

@ -249,6 +249,8 @@ shost_rd_attr(cmd_per_lun, "%hd\n");
shost_rd_attr(can_queue, "%hd\n");
shost_rd_attr(sg_tablesize, "%hu\n");
shost_rd_attr(unchecked_isa_dma, "%d\n");
shost_rd_attr(prot_capabilities, "%u\n");
shost_rd_attr(prot_guard_type, "%hd\n");
shost_rd_attr2(proc_name, hostt->proc_name, "%s\n");
static struct attribute *scsi_sysfs_shost_attrs[] = {
@ -263,6 +265,8 @@ static struct attribute *scsi_sysfs_shost_attrs[] = {
&dev_attr_hstate.attr,
&dev_attr_supported_mode.attr,
&dev_attr_active_mode.attr,
&dev_attr_prot_capabilities.attr,
&dev_attr_prot_guard_type.attr,
NULL
};

View file

@ -636,6 +636,10 @@ struct Scsi_Host {
*/
unsigned int max_host_blocked;
/* Protection Information */
unsigned int prot_capabilities;
unsigned char prot_guard_type;
/*
* q used for scsi_tgt msgs, async events or any other requests that
* need to be processed in userspace
@ -756,6 +760,86 @@ extern struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost,
extern void scsi_free_host_dev(struct scsi_device *);
extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
/*
* DIF defines the exchange of protection information between
* initiator and SBC block device.
*
* DIX defines the exchange of protection information between OS and
* initiator.
*/
enum scsi_host_prot_capabilities {
SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
};
/*
* SCSI hosts which support the Data Integrity Extensions must
* indicate their capabilities by setting the prot_capabilities using
* this call.
*/
static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
{
shost->prot_capabilities = mask;
}
static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
{
return shost->prot_capabilities;
}
static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
{
switch (target_type) {
case 1: return shost->prot_capabilities & SHOST_DIF_TYPE1_PROTECTION;
case 2: return shost->prot_capabilities & SHOST_DIF_TYPE2_PROTECTION;
case 3: return shost->prot_capabilities & SHOST_DIF_TYPE3_PROTECTION;
}
return 0;
}
static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
{
switch (target_type) {
case 0: return shost->prot_capabilities & SHOST_DIX_TYPE0_PROTECTION;
case 1: return shost->prot_capabilities & SHOST_DIX_TYPE1_PROTECTION;
case 2: return shost->prot_capabilities & SHOST_DIX_TYPE2_PROTECTION;
case 3: return shost->prot_capabilities & SHOST_DIX_TYPE3_PROTECTION;
}
return 0;
}
/*
* All DIX-capable initiators must support the T10-mandated CRC
* checksum. Controllers can optionally implement the IP checksum
* scheme which has much lower impact on system performance. Note
* that the main rationale for the checksum is to match integrity
* metadata with data. Detecting bit errors are a job for ECC memory
* and buses.
*/
enum scsi_host_guard_type {
SHOST_DIX_GUARD_CRC = 1 << 0,
SHOST_DIX_GUARD_IP = 1 << 1,
};
static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
{
shost->prot_guard_type = type;
}
static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
{
return shost->prot_guard_type;
}
/* legacy interfaces */
extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int);
extern void scsi_unregister(struct Scsi_Host *);