From d3301874083874f8a0ac88aa1bb7da6b62df34d2 Mon Sep 17 00:00:00 2001 From: Mike Anderson Date: Thu, 16 Jun 2005 11:12:38 -0700 Subject: [PATCH] [SCSI] host state model update: replace old host bitmap state Migrate the current SCSI host state model to a model like SCSI device is using. Signed-off-by: Mike Anderson Rejections fixed up and Signed-off-by: James Bottomley --- drivers/scsi/hosts.c | 88 ++++++++++++++++++++++++++++++++++++--- drivers/scsi/scsi.c | 2 +- drivers/scsi/scsi_error.c | 7 ++-- drivers/scsi/scsi_ioctl.c | 3 +- drivers/scsi/scsi_lib.c | 4 +- drivers/scsi/scsi_sysfs.c | 62 +++++++++++++++++++++++++++ drivers/scsi/sg.c | 3 +- include/scsi/scsi_host.h | 14 ++++--- 8 files changed, 162 insertions(+), 21 deletions(-) diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index 5feb886c339..6828ca305c2 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -51,6 +51,82 @@ static struct class shost_class = { .release = scsi_host_cls_release, }; +/** + * 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. + **/ +int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state) +{ + 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; + + } + 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_host_cancel - cancel outstanding IO to this host * @shost: pointer to struct Scsi_Host @@ -60,12 +136,11 @@ static void scsi_host_cancel(struct Scsi_Host *shost, int recovery) { struct scsi_device *sdev; - set_bit(SHOST_CANCEL, &shost->shost_state); + scsi_host_set_state(shost, SHOST_CANCEL); shost_for_each_device(sdev, shost) { scsi_device_cancel(sdev, recovery); } - wait_event(shost->host_wait, (!test_bit(SHOST_RECOVERY, - &shost->shost_state))); + wait_event(shost->host_wait, (shost->shost_state != SHOST_RECOVERY)); } /** @@ -78,7 +153,7 @@ void scsi_remove_host(struct Scsi_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 +190,7 @@ 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 +301,7 @@ 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 +458,7 @@ 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; diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index d14523d7e44..fb85b3ced7b 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -627,7 +627,7 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd) spin_lock_irqsave(host->host_lock, flags); scsi_cmd_get_serial(host, cmd); - if (unlikely(test_bit(SHOST_CANCEL, &host->shost_state))) { + if (unlikely(host->shost_state == SHOST_CANCEL)) { cmd->result = (DID_NO_CONNECT << 16); scsi_done(cmd); } else { diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index 0fc8b48f052..e9c451ba71f 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -75,7 +75,7 @@ int scsi_eh_scmd_add(struct scsi_cmnd *scmd, int eh_flag) scmd->eh_eflags |= eh_flag; list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q); - set_bit(SHOST_RECOVERY, &shost->shost_state); + scsi_host_set_state(shost, SHOST_RECOVERY); shost->host_failed++; scsi_eh_wakeup(shost); spin_unlock_irqrestore(shost->host_lock, flags); @@ -197,7 +197,8 @@ int scsi_block_when_processing_errors(struct scsi_device *sdev) { int online; - wait_event(sdev->host->host_wait, (!test_bit(SHOST_RECOVERY, &sdev->host->shost_state))); + wait_event(sdev->host->host_wait, (sdev->host->shost_state != + SHOST_RECOVERY)); online = scsi_device_online(sdev); @@ -1458,7 +1459,7 @@ static void scsi_restart_operations(struct Scsi_Host *shost) SCSI_LOG_ERROR_RECOVERY(3, printk("%s: waking up host to restart\n", __FUNCTION__)); - clear_bit(SHOST_RECOVERY, &shost->shost_state); + scsi_host_set_state(shost, SHOST_RUNNING); wake_up(&shost->host_wait); diff --git a/drivers/scsi/scsi_ioctl.c b/drivers/scsi/scsi_ioctl.c index 7a6b530115a..f5bf5c07be9 100644 --- a/drivers/scsi/scsi_ioctl.c +++ b/drivers/scsi/scsi_ioctl.c @@ -475,8 +475,7 @@ int scsi_nonblockable_ioctl(struct scsi_device *sdev, int cmd, * error processing, as long as the device was opened * non-blocking */ if (filp && filp->f_flags & O_NONBLOCK) { - if (test_bit(SHOST_RECOVERY, - &sdev->host->shost_state)) + if (sdev->host->shost_state == SHOST_RECOVERY) return -ENODEV; } else if (!scsi_block_when_processing_errors(sdev)) return -ENODEV; diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 7a91ca3d32a..060010bccab 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -348,7 +348,7 @@ void scsi_device_unbusy(struct scsi_device *sdev) spin_lock_irqsave(shost->host_lock, flags); shost->host_busy--; - if (unlikely(test_bit(SHOST_RECOVERY, &shost->shost_state) && + if (unlikely((shost->shost_state == SHOST_RECOVERY) && shost->host_failed)) scsi_eh_wakeup(shost); spin_unlock(shost->host_lock); @@ -1207,7 +1207,7 @@ static inline int scsi_host_queue_ready(struct request_queue *q, struct Scsi_Host *shost, struct scsi_device *sdev) { - if (test_bit(SHOST_RECOVERY, &shost->shost_state)) + if (shost->shost_state == SHOST_RECOVERY) return 0; if (shost->host_busy == 0 && shost->host_blocked) { /* diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index beed7fbe1cb..dae59d1da07 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -48,6 +48,30 @@ const char *scsi_device_state_name(enum scsi_device_state state) return name; } +static struct { + enum scsi_host_state value; + char *name; +} shost_states[] = { + { SHOST_CREATED, "created" }, + { SHOST_RUNNING, "running" }, + { SHOST_CANCEL, "cancel" }, + { SHOST_DEL, "deleted" }, + { SHOST_RECOVERY, "recovery" }, +}; +const char *scsi_host_state_name(enum scsi_host_state state) +{ + int i; + char *name = NULL; + + for (i = 0; i < sizeof(shost_states)/sizeof(shost_states[0]); i++) { + if (shost_states[i].value == state) { + name = shost_states[i].name; + break; + } + } + return name; +} + static int check_set(unsigned int *val, char *src) { char *last; @@ -124,6 +148,43 @@ static ssize_t store_scan(struct class_device *class_dev, const char *buf, }; static CLASS_DEVICE_ATTR(scan, S_IWUSR, NULL, store_scan); +static ssize_t +store_shost_state(struct class_device *class_dev, const char *buf, size_t count) +{ + int i; + struct Scsi_Host *shost = class_to_shost(class_dev); + enum scsi_host_state state = 0; + + for (i = 0; i < sizeof(shost_states)/sizeof(shost_states[0]); i++) { + const int len = strlen(shost_states[i].name); + if (strncmp(shost_states[i].name, buf, len) == 0 && + buf[len] == '\n') { + state = shost_states[i].value; + break; + } + } + if (!state) + return -EINVAL; + + if (scsi_host_set_state(shost, state)) + return -EINVAL; + return count; +} + +static ssize_t +show_shost_state(struct class_device *class_dev, char *buf) +{ + struct Scsi_Host *shost = class_to_shost(class_dev); + const char *name = scsi_host_state_name(shost->shost_state); + + if (!name) + return -EINVAL; + + return snprintf(buf, 20, "%s\n", name); +} + +static CLASS_DEVICE_ATTR(state, S_IRUGO | S_IWUSR, show_shost_state, store_shost_state); + shost_rd_attr(unique_id, "%u\n"); shost_rd_attr(host_busy, "%hu\n"); shost_rd_attr(cmd_per_lun, "%hd\n"); @@ -139,6 +200,7 @@ static struct class_device_attribute *scsi_sysfs_shost_attrs[] = { &class_device_attr_unchecked_isa_dma, &class_device_attr_proc_name, &class_device_attr_scan, + &class_device_attr_state, NULL }; diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 51292f269ce..14fb179b384 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -1027,8 +1027,7 @@ sg_ioctl(struct inode *inode, struct file *filp, if (sdp->detached) return -ENODEV; if (filp->f_flags & O_NONBLOCK) { - if (test_bit(SHOST_RECOVERY, - &sdp->device->host->shost_state)) + if (sdp->device->host->shost_state == SHOST_RECOVERY) return -EBUSY; } else if (!scsi_block_when_processing_errors(sdp->device)) return -EBUSY; diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index 81d5234f677..0b1e275b269 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -429,12 +429,15 @@ struct scsi_host_template { }; /* - * shost states + * shost state: If you alter this, you also need to alter scsi_sysfs.c + * (for the ascii descriptions) and the state model enforcer: + * scsi_host_set_state() */ -enum { - SHOST_ADD, - SHOST_DEL, +enum scsi_host_state { + SHOST_CREATED = 1, + SHOST_RUNNING, SHOST_CANCEL, + SHOST_DEL, SHOST_RECOVERY, }; @@ -575,7 +578,7 @@ struct Scsi_Host { unsigned int irq; - unsigned long shost_state; + enum scsi_host_state shost_state; /* ldm bits */ struct device shost_gendev; @@ -633,6 +636,7 @@ extern void scsi_remove_host(struct Scsi_Host *); extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); extern void scsi_host_put(struct Scsi_Host *t); extern struct Scsi_Host *scsi_host_lookup(unsigned short); +extern const char *scsi_host_state_name(enum scsi_host_state); extern u64 scsi_calculate_bounce_limit(struct Scsi_Host *); -- 2.20.1