linux/include/scsi/scsi_transport_sas.h
Dan Williams 87c8331fcf [SCSI] libsas: prevent domain rediscovery competing with ata error handling
libata error handling provides for a timeout for link recovery.  libsas
must not rescan for previously known devices in this interval otherwise
it may remove a device that is simply waiting for its link to recover.
Let libata-eh make the determination of when the link is stable and
prevent libsas (host workqueue) from taking action while this
determination is pending.

Using a mutex (ha->disco_mutex) to flush and disable revalidation while
eh is running requires any discovery action that may block on eh be
moved to its own context outside the lock.  Probing ATA devices
explicitly waits on ata-eh and the cache-flush-io issued during device
removal may also pend awaiting eh completion.  Essentially any rphy
add/remove activity needs to run outside the lock.

This adds two new cleanup states for sas_unregister_domain_devices()
'allocated-but-not-probed', and 'flagged-for-destruction'.  In the
'allocated-but-not-probed' state  dev->rphy points to a rphy that is
known to have not been through a sas_rphy_add() event.  At domain
teardown check if this device is still pending probe and cleanup
accordingly.  Similarly if a device has already been queued for removal
then sas_unregister_domain_devices has nothing to do.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 13:52:34 -06:00

229 lines
6.4 KiB
C

#ifndef SCSI_TRANSPORT_SAS_H
#define SCSI_TRANSPORT_SAS_H
#include <linux/transport_class.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <scsi/sas.h>
struct scsi_transport_template;
struct sas_rphy;
struct request;
enum sas_device_type {
SAS_PHY_UNUSED = 0,
SAS_END_DEVICE = 1,
SAS_EDGE_EXPANDER_DEVICE = 2,
SAS_FANOUT_EXPANDER_DEVICE = 3,
};
static inline int sas_protocol_ata(enum sas_protocol proto)
{
return ((proto & SAS_PROTOCOL_SATA) ||
(proto & SAS_PROTOCOL_STP))? 1 : 0;
}
enum sas_linkrate {
/* These Values are defined in the SAS standard */
SAS_LINK_RATE_UNKNOWN = 0,
SAS_PHY_DISABLED = 1,
SAS_PHY_RESET_PROBLEM = 2,
SAS_SATA_SPINUP_HOLD = 3,
SAS_SATA_PORT_SELECTOR = 4,
SAS_PHY_RESET_IN_PROGRESS = 5,
SAS_LINK_RATE_1_5_GBPS = 8,
SAS_LINK_RATE_G1 = SAS_LINK_RATE_1_5_GBPS,
SAS_LINK_RATE_3_0_GBPS = 9,
SAS_LINK_RATE_G2 = SAS_LINK_RATE_3_0_GBPS,
SAS_LINK_RATE_6_0_GBPS = 10,
/* These are virtual to the transport class and may never
* be signalled normally since the standard defined field
* is only 4 bits */
SAS_LINK_RATE_FAILED = 0x10,
SAS_PHY_VIRTUAL = 0x11,
};
struct sas_identify {
enum sas_device_type device_type;
enum sas_protocol initiator_port_protocols;
enum sas_protocol target_port_protocols;
u64 sas_address;
u8 phy_identifier;
};
struct sas_phy {
struct device dev;
int number;
int enabled;
/* phy identification */
struct sas_identify identify;
/* phy attributes */
enum sas_linkrate negotiated_linkrate;
enum sas_linkrate minimum_linkrate_hw;
enum sas_linkrate minimum_linkrate;
enum sas_linkrate maximum_linkrate_hw;
enum sas_linkrate maximum_linkrate;
/* link error statistics */
u32 invalid_dword_count;
u32 running_disparity_error_count;
u32 loss_of_dword_sync_count;
u32 phy_reset_problem_count;
/* for the list of phys belonging to a port */
struct list_head port_siblings;
struct work_struct reset_work;
};
#define dev_to_phy(d) \
container_of((d), struct sas_phy, dev)
#define transport_class_to_phy(dev) \
dev_to_phy((dev)->parent)
#define phy_to_shost(phy) \
dev_to_shost((phy)->dev.parent)
struct request_queue;
struct sas_rphy {
struct device dev;
struct sas_identify identify;
struct list_head list;
struct request_queue *q;
u32 scsi_target_id;
};
#define dev_to_rphy(d) \
container_of((d), struct sas_rphy, dev)
#define transport_class_to_rphy(dev) \
dev_to_rphy((dev)->parent)
#define rphy_to_shost(rphy) \
dev_to_shost((rphy)->dev.parent)
#define target_to_rphy(targ) \
dev_to_rphy((targ)->dev.parent)
struct sas_end_device {
struct sas_rphy rphy;
/* flags */
unsigned ready_led_meaning:1;
unsigned tlr_supported:1;
unsigned tlr_enabled:1;
/* parameters */
u16 I_T_nexus_loss_timeout;
u16 initiator_response_timeout;
};
#define rphy_to_end_device(r) \
container_of((r), struct sas_end_device, rphy)
struct sas_expander_device {
int level;
int next_port_id;
#define SAS_EXPANDER_VENDOR_ID_LEN 8
char vendor_id[SAS_EXPANDER_VENDOR_ID_LEN+1];
#define SAS_EXPANDER_PRODUCT_ID_LEN 16
char product_id[SAS_EXPANDER_PRODUCT_ID_LEN+1];
#define SAS_EXPANDER_PRODUCT_REV_LEN 4
char product_rev[SAS_EXPANDER_PRODUCT_REV_LEN+1];
#define SAS_EXPANDER_COMPONENT_VENDOR_ID_LEN 8
char component_vendor_id[SAS_EXPANDER_COMPONENT_VENDOR_ID_LEN+1];
u16 component_id;
u8 component_revision_id;
struct sas_rphy rphy;
};
#define rphy_to_expander_device(r) \
container_of((r), struct sas_expander_device, rphy)
struct sas_port {
struct device dev;
int port_identifier;
int num_phys;
/* port flags */
unsigned int is_backlink:1;
/* the other end of the link */
struct sas_rphy *rphy;
struct mutex phy_list_mutex;
struct list_head phy_list;
};
#define dev_to_sas_port(d) \
container_of((d), struct sas_port, dev)
#define transport_class_to_sas_port(dev) \
dev_to_sas_port((dev)->parent)
struct sas_phy_linkrates {
enum sas_linkrate maximum_linkrate;
enum sas_linkrate minimum_linkrate;
};
/* The functions by which the transport class and the driver communicate */
struct sas_function_template {
int (*get_linkerrors)(struct sas_phy *);
int (*get_enclosure_identifier)(struct sas_rphy *, u64 *);
int (*get_bay_identifier)(struct sas_rphy *);
int (*phy_reset)(struct sas_phy *, int);
int (*phy_enable)(struct sas_phy *, int);
int (*set_phy_speed)(struct sas_phy *, struct sas_phy_linkrates *);
int (*smp_handler)(struct Scsi_Host *, struct sas_rphy *, struct request *);
};
void sas_remove_children(struct device *);
extern void sas_remove_host(struct Scsi_Host *);
extern struct sas_phy *sas_phy_alloc(struct device *, int);
extern void sas_phy_free(struct sas_phy *);
extern int sas_phy_add(struct sas_phy *);
extern void sas_phy_delete(struct sas_phy *);
extern int scsi_is_sas_phy(const struct device *);
unsigned int sas_tlr_supported(struct scsi_device *);
unsigned int sas_is_tlr_enabled(struct scsi_device *);
void sas_disable_tlr(struct scsi_device *);
void sas_enable_tlr(struct scsi_device *);
extern struct sas_rphy *sas_end_device_alloc(struct sas_port *);
extern struct sas_rphy *sas_expander_alloc(struct sas_port *, enum sas_device_type);
void sas_rphy_free(struct sas_rphy *);
extern int sas_rphy_add(struct sas_rphy *);
extern void sas_rphy_remove(struct sas_rphy *);
extern void sas_rphy_delete(struct sas_rphy *);
extern void sas_rphy_unlink(struct sas_rphy *);
extern int scsi_is_sas_rphy(const struct device *);
struct sas_port *sas_port_alloc(struct device *, int);
struct sas_port *sas_port_alloc_num(struct device *);
int sas_port_add(struct sas_port *);
void sas_port_free(struct sas_port *);
void sas_port_delete(struct sas_port *);
void sas_port_add_phy(struct sas_port *, struct sas_phy *);
void sas_port_delete_phy(struct sas_port *, struct sas_phy *);
void sas_port_mark_backlink(struct sas_port *);
int scsi_is_sas_port(const struct device *);
extern struct scsi_transport_template *
sas_attach_transport(struct sas_function_template *);
extern void sas_release_transport(struct scsi_transport_template *);
int sas_read_port_mode_page(struct scsi_device *);
static inline int
scsi_is_sas_expander_device(struct device *dev)
{
struct sas_rphy *rphy;
if (!scsi_is_sas_rphy(dev))
return 0;
rphy = dev_to_rphy(dev);
return rphy->identify.device_type == SAS_FANOUT_EXPANDER_DEVICE ||
rphy->identify.device_type == SAS_EDGE_EXPANDER_DEVICE;
}
#define scsi_is_sas_phy_local(phy) scsi_is_host_device((phy)->dev.parent)
#endif /* SCSI_TRANSPORT_SAS_H */