diff options
Diffstat (limited to 'drivers/scsi/hosts.c')
| -rw-r--r-- | drivers/scsi/hosts.c | 150 |
1 files changed, 119 insertions, 31 deletions
diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index 5feb886c3392..71dd1ebbe58f 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -24,11 +24,13 @@ #include <linux/module.h> #include <linux/blkdev.h> #include <linux/kernel.h> +#include <linux/kthread.h> #include <linux/string.h> #include <linux/mm.h> #include <linux/init.h> #include <linux/completion.h> #include <linux/transport_class.h> +#include <linux/platform_device.h> #include <scsi/scsi_device.h> #include <scsi/scsi_host.h> @@ -52,21 +54,100 @@ 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: + case SHOST_CANCEL_RECOVERY: + break; + default: + goto illegal; + } + break; + + case SHOST_DEL: + switch (oldstate) { + case SHOST_CANCEL: + case SHOST_DEL_RECOVERY: + break; + default: + goto illegal; + } + break; - set_bit(SHOST_CANCEL, &shost->shost_state); - shost_for_each_device(sdev, shost) { - scsi_device_cancel(sdev, recovery); + case SHOST_CANCEL_RECOVERY: + switch (oldstate) { + case SHOST_CANCEL: + case SHOST_RECOVERY: + break; + default: + goto illegal; + } + break; + + case SHOST_DEL_RECOVERY: + switch (oldstate) { + case SHOST_CANCEL_RECOVERY: + break; + default: + goto illegal; + } + break; } - 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 @@ -74,15 +155,29 @@ static void scsi_host_cancel(struct Scsi_Host *shost, int recovery) **/ void scsi_remove_host(struct Scsi_Host *shost) { + unsigned long flags; + down(&shost->scan_mutex); + spin_lock_irqsave(shost->host_lock, flags); + if (scsi_host_set_state(shost, SHOST_CANCEL)) + if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) { + spin_unlock_irqrestore(shost->host_lock, flags); + up(&shost->scan_mutex); + return; + } + spin_unlock_irqrestore(shost->host_lock, flags); + 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); + spin_lock_irqsave(shost->host_lock, flags); + if (scsi_host_set_state(shost, SHOST_DEL)) + BUG_ON(scsi_host_set_state(shost, SHOST_DEL_RECOVERY)); + spin_unlock_irqrestore(shost->host_lock, flags); transport_unregister_device(&shost->shost_gendev); class_device_unregister(&shost->shost_classdev); device_del(&shost->shost_gendev); + scsi_proc_hostdir_rm(shost->hostt); } EXPORT_SYMBOL(scsi_remove_host); @@ -115,7 +210,7 @@ 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); @@ -164,19 +259,11 @@ static void scsi_host_dev_release(struct device *dev) struct Scsi_Host *shost = dev_to_shost(dev); struct device *parent = dev->parent; - if (shost->ehandler) { - DECLARE_COMPLETION(sem); - shost->eh_notify = &sem; - shost->eh_kill = 1; - up(shost->eh_wait); - wait_for_completion(&sem); - shost->eh_notify = NULL; - } - + if (shost->ehandler) + kthread_stop(shost->ehandler); if (shost->work_q) destroy_workqueue(shost->work_q); - scsi_proc_hostdir_rm(shost->hostt); scsi_destroy_command_freelist(shost); kfree(shost->shost_data); @@ -201,8 +288,8 @@ static void scsi_host_dev_release(struct device *dev) struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize) { struct Scsi_Host *shost; - int gfp_mask = GFP_KERNEL, rval; - DECLARE_COMPLETION(complete); + gfp_t gfp_mask = GFP_KERNEL; + int rval; if (sht->unchecked_isa_dma && privsize) gfp_mask |= __GFP_DMA; @@ -226,6 +313,7 @@ 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); @@ -307,12 +395,12 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize) snprintf(shost->shost_classdev.class_id, BUS_ID_SIZE, "host%d", shost->host_no); - shost->eh_notify = &complete; - rval = kernel_thread(scsi_error_handler, shost, 0); - if (rval < 0) + shost->ehandler = kthread_run(scsi_error_handler, shost, + "scsi_eh_%d", shost->host_no); + if (IS_ERR(shost->ehandler)) { + rval = PTR_ERR(shost->ehandler); goto fail_destroy_freelist; - wait_for_completion(&complete); - shost->eh_notify = NULL; + } scsi_proc_hostdir_add(shost->hostt); return shost; @@ -382,7 +470,7 @@ 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; |