diff options
Diffstat (limited to 'drivers/scsi/hosts.c')
-rw-r--r-- | drivers/scsi/hosts.c | 90 |
1 files changed, 76 insertions, 14 deletions
diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index 5feb886c3392..8640ad1c17e2 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -52,21 +52,80 @@ static struct class shost_class = { }; /** - * scsi_host_cancel - cancel outstanding IO to this host - * @shost: pointer to struct Scsi_Host - * recovery: recovery requested to run. + * scsi_host_set_state - Take the given host through the host + * state model. + * @shost: scsi host to change the state of. + * @state: state to change to. + * + * Returns zero if unsuccessful or an error if the requested + * transition is illegal. **/ -static void scsi_host_cancel(struct Scsi_Host *shost, int recovery) +int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state) { - struct scsi_device *sdev; + enum scsi_host_state oldstate = shost->shost_state; + + if (state == oldstate) + return 0; + + switch (state) { + case SHOST_CREATED: + /* There are no legal states that come back to + * created. This is the manually initialised start + * state */ + goto illegal; + + case SHOST_RUNNING: + switch (oldstate) { + case SHOST_CREATED: + case SHOST_RECOVERY: + break; + default: + goto illegal; + } + break; + + case SHOST_RECOVERY: + switch (oldstate) { + case SHOST_RUNNING: + break; + default: + goto illegal; + } + break; + + case SHOST_CANCEL: + switch (oldstate) { + case SHOST_CREATED: + case SHOST_RUNNING: + break; + default: + goto illegal; + } + break; + + case SHOST_DEL: + switch (oldstate) { + case SHOST_CANCEL: + break; + default: + goto illegal; + } + break; - set_bit(SHOST_CANCEL, &shost->shost_state); - shost_for_each_device(sdev, shost) { - scsi_device_cancel(sdev, recovery); } - wait_event(shost->host_wait, (!test_bit(SHOST_RECOVERY, - &shost->shost_state))); + shost->shost_state = state; + return 0; + + illegal: + SCSI_LOG_ERROR_RECOVERY(1, + dev_printk(KERN_ERR, &shost->shost_gendev, + "Illegal host state transition" + "%s->%s\n", + scsi_host_state_name(oldstate), + scsi_host_state_name(state))); + return -EINVAL; } +EXPORT_SYMBOL(scsi_host_set_state); /** * scsi_remove_host - remove a scsi host @@ -74,11 +133,13 @@ static void scsi_host_cancel(struct Scsi_Host *shost, int recovery) **/ void scsi_remove_host(struct Scsi_Host *shost) { + down(&shost->scan_mutex); + scsi_host_set_state(shost, SHOST_CANCEL); + up(&shost->scan_mutex); scsi_forget_host(shost); - scsi_host_cancel(shost, 0); scsi_proc_host_rm(shost); - set_bit(SHOST_DEL, &shost->shost_state); + scsi_host_set_state(shost, SHOST_DEL); transport_unregister_device(&shost->shost_gendev); class_device_unregister(&shost->shost_classdev); @@ -115,7 +176,7 @@ int scsi_add_host(struct Scsi_Host *shost, struct device *dev) if (error) goto out; - set_bit(SHOST_ADD, &shost->shost_state); + scsi_host_set_state(shost, SHOST_RUNNING); get_device(shost->shost_gendev.parent); error = class_device_add(&shost->shost_classdev); @@ -226,6 +287,7 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize) spin_lock_init(&shost->default_lock); scsi_assign_lock(shost, &shost->default_lock); + shost->shost_state = SHOST_CREATED; INIT_LIST_HEAD(&shost->__devices); INIT_LIST_HEAD(&shost->__targets); INIT_LIST_HEAD(&shost->eh_cmd_q); @@ -382,7 +444,7 @@ EXPORT_SYMBOL(scsi_host_lookup); **/ struct Scsi_Host *scsi_host_get(struct Scsi_Host *shost) { - if (test_bit(SHOST_DEL, &shost->shost_state) || + if ((shost->shost_state == SHOST_DEL) || !get_device(&shost->shost_gendev)) return NULL; return shost; |