The current target allocation code registeres each possible target
with sysfs; it will be deleted again if no useable LUN on this target
was found. This results in a string of 'target add/target remove' uevents.
This patch reworks the target allocation code so that only
uevents for existing targets are sent. The sysfs registration
is split off from the existing scsi_target_alloc() into a
in a new scsi_add_target() function, which should be called
whenever an existing target is found. Only then a uevent is
sent, so we'll be generating events for existing targets only.
And while we're at it the cleanup code has been moved to the
->release function, so that the target will always be useable
as long as the reference to it is held.
Signed-off-by: Hannes Reinecke <hare@xxxxxxx>
Signed-off-by: Kay Sievers <kay.sievers@xxxxxxxx>
---
drivers/scsi/scsi_scan.c | 74 ++++++++++++++++++++++++++++---------------
include/scsi/scsi_device.h | 3 +-
2 files changed, 50 insertions(+), 27 deletions(-)
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index e1644b2..be54354 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -326,7 +326,15 @@ static void scsi_target_dev_release(struct device *dev)
{
struct device *parent = dev->parent;
struct scsi_target *starget = to_scsi_target(dev);
+ struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
+ unsigned long flags;
+ transport_destroy_device(&starget->dev);
+ spin_lock_irqsave(shost->host_lock, flags);
+ if (shost->hostt->target_destroy)
+ shost->hostt->target_destroy(starget);
+ list_del_init(&starget->siblings);
+ spin_unlock_irqrestore(shost->host_lock, flags);
kfree(starget);
put_device(parent);
}
@@ -406,7 +414,7 @@ static struct scsi_target *scsi_alloc_target(struct device *parent,
starget->channel = channel;
INIT_LIST_HEAD(&starget->siblings);
INIT_LIST_HEAD(&starget->devices);
- starget->state = STARGET_RUNNING;
+ starget->state = STARGET_CREATED;
starget->scsi_level = SCSI_2;
retry:
spin_lock_irqsave(shost->host_lock, flags);
@@ -419,18 +427,6 @@ static struct scsi_target *scsi_alloc_target(struct device *parent,
spin_unlock_irqrestore(shost->host_lock, flags);
/* allocate and add */
transport_setup_device(dev);
- error = device_add(dev);
- if (error) {
- dev_err(dev, "target device_add failed, error %d\n", error);
- spin_lock_irqsave(shost->host_lock, flags);
- list_del_init(&starget->siblings);
- spin_unlock_irqrestore(shost->host_lock, flags);
- transport_destroy_device(dev);
- put_device(parent);
- kfree(starget);
- return NULL;
- }
- transport_add_device(dev);
if (shost->hostt->target_alloc) {
error = shost->hostt->target_alloc(starget);
@@ -438,9 +434,12 @@ static struct scsi_target *scsi_alloc_target(struct device *parent,
dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error);
/* don't want scsi_target_reap to do the final
* put because it will be under the host lock */
- get_device(dev);
- scsi_target_reap(starget);
- put_device(dev);
+ spin_lock_irqsave(shost->host_lock, flags);
+ list_del_init(&starget->siblings);
+ spin_unlock_irqrestore(shost->host_lock, flags);
+ transport_destroy_device(dev);
+ put_device(parent);
+ kfree(starget);
return NULL;
}
}
@@ -463,21 +462,31 @@ static struct scsi_target *scsi_alloc_target(struct device *parent,
goto retry;
}
+static int scsi_add_target(struct scsi_target *starget)
+{
+ int error;
+
+ error = device_add(&starget->dev);
+ if (error) {
+ dev_err(&starget->dev, "target device_add failed, error %d\n", error);
+ get_device(&starget->dev);
+ scsi_target_reap(starget);
+ put_device(&starget->dev);
+ return error;
+ }
+ transport_add_device(&starget->dev);
+ starget->state = STARGET_RUNNING;
+
+ return 0;
+}
+
static void scsi_target_reap_usercontext(struct work_struct *work)
{
struct scsi_target *starget =
container_of(work, struct scsi_target, ew.work);
- struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
- unsigned long flags;
transport_remove_device(&starget->dev);
device_del(&starget->dev);
- transport_destroy_device(&starget->dev);
- spin_lock_irqsave(shost->host_lock, flags);
- if (shost->hostt->target_destroy)
- shost->hostt->target_destroy(starget);
- list_del_init(&starget->siblings);
- spin_unlock_irqrestore(shost->host_lock, flags);
put_device(&starget->dev);
}
@@ -497,7 +506,12 @@ void scsi_target_reap(struct scsi_target *starget)
spin_lock_irqsave(shost->host_lock, flags);
if (--starget->reap_ref == 0 && list_empty(&starget->devices)) {
- BUG_ON(starget->state == STARGET_DEL);
+ if (starget->state == STARGET_CREATED) {
+ spin_unlock_irqrestore(shost->host_lock, flags);
+ starget->state = STARGET_DEL;
+ put_device(&starget->dev);
+ return;
+ }
starget->state = STARGET_DEL;
spin_unlock_irqrestore(shost->host_lock, flags);
execute_in_process_context(scsi_target_reap_usercontext,
@@ -1056,12 +1070,17 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget,
scsi_inq_str(vend, result, 8, 16),
scsi_inq_str(mod, result, 16, 32));
});
+ if (scsi_add_target(starget))
+ goto out_free_result;
+
}
-
res = SCSI_SCAN_TARGET_PRESENT;
goto out_free_result;
}
+ if (lun == 0 && scsi_add_target(starget))
+ goto out_free_result;
+
/*
* Some targets may set slight variations of PQ and PDT to signal
* that no LUN is present, so don't add sdev in these cases.
@@ -1886,6 +1905,9 @@ struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
if (!starget)
goto out;
+ if (scsi_add_target(starget))
+ goto out;
+
sdev = scsi_alloc_sdev(starget, 0, NULL);
if (sdev) {
sdev->sdev_gendev.parent = get_device(&starget->dev);
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index b8b19e2..f6a9fe0 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -181,7 +181,8 @@ struct scsi_device {
sdev_printk(prefix, (scmd)->device, fmt, ##a)
enum scsi_target_state {
- STARGET_RUNNING = 1,
+ STARGET_CREATED = 1,
+ STARGET_RUNNING,
STARGET_DEL,
};
--
1.5.2.4
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