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authorIngo Molnar <mingo@elte.hu>2009-09-15 12:18:15 +0200
committerIngo Molnar <mingo@elte.hu>2009-09-15 12:18:15 +0200
commitdca2d6ac09d9ef59ff46820d4f0c94b08a671202 (patch)
treefdec753b842dad09e3a4151954fab3eb5c43500d /drivers/scsi/device_handler/scsi_dh.c
parentd6a65dffb30d8636b1e5d4c201564ef401a246cf (diff)
parent18240904960a39e582ced8ba8ececb10b8c22dd3 (diff)
Merge branch 'linus' into tracing/hw-breakpoints
Conflicts: arch/x86/kernel/process_64.c Semantic conflict fixed in: arch/x86/kvm/x86.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'drivers/scsi/device_handler/scsi_dh.c')
-rw-r--r--drivers/scsi/device_handler/scsi_dh.c56
1 files changed, 49 insertions, 7 deletions
diff --git a/drivers/scsi/device_handler/scsi_dh.c b/drivers/scsi/device_handler/scsi_dh.c
index a518f2eff19..3ee1cbc8947 100644
--- a/drivers/scsi/device_handler/scsi_dh.c
+++ b/drivers/scsi/device_handler/scsi_dh.c
@@ -153,12 +153,24 @@ static int scsi_dh_handler_attach(struct scsi_device *sdev,
if (sdev->scsi_dh_data) {
if (sdev->scsi_dh_data->scsi_dh != scsi_dh)
err = -EBUSY;
- } else if (scsi_dh->attach)
+ else
+ kref_get(&sdev->scsi_dh_data->kref);
+ } else if (scsi_dh->attach) {
err = scsi_dh->attach(sdev);
-
+ if (!err) {
+ kref_init(&sdev->scsi_dh_data->kref);
+ sdev->scsi_dh_data->sdev = sdev;
+ }
+ }
return err;
}
+static void __detach_handler (struct kref *kref)
+{
+ struct scsi_dh_data *scsi_dh_data = container_of(kref, struct scsi_dh_data, kref);
+ scsi_dh_data->scsi_dh->detach(scsi_dh_data->sdev);
+}
+
/*
* scsi_dh_handler_detach - Detach a device handler from a device
* @sdev - SCSI device the device handler should be detached from
@@ -180,7 +192,7 @@ static void scsi_dh_handler_detach(struct scsi_device *sdev,
scsi_dh = sdev->scsi_dh_data->scsi_dh;
if (scsi_dh && scsi_dh->detach)
- scsi_dh->detach(sdev);
+ kref_put(&sdev->scsi_dh_data->kref, __detach_handler);
}
/*
@@ -440,6 +452,39 @@ int scsi_dh_activate(struct request_queue *q)
EXPORT_SYMBOL_GPL(scsi_dh_activate);
/*
+ * scsi_dh_set_params - set the parameters for the device as per the
+ * string specified in params.
+ * @q - Request queue that is associated with the scsi_device for
+ * which the parameters to be set.
+ * @params - parameters in the following format
+ * "no_of_params\0param1\0param2\0param3\0...\0"
+ * for example, string for 2 parameters with value 10 and 21
+ * is specified as "2\010\021\0".
+ */
+int scsi_dh_set_params(struct request_queue *q, const char *params)
+{
+ int err = -SCSI_DH_NOSYS;
+ unsigned long flags;
+ struct scsi_device *sdev;
+ struct scsi_device_handler *scsi_dh = NULL;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ sdev = q->queuedata;
+ if (sdev && sdev->scsi_dh_data)
+ scsi_dh = sdev->scsi_dh_data->scsi_dh;
+ if (scsi_dh && scsi_dh->set_params && get_device(&sdev->sdev_gendev))
+ err = 0;
+ spin_unlock_irqrestore(q->queue_lock, flags);
+
+ if (err)
+ return err;
+ err = scsi_dh->set_params(sdev, params);
+ put_device(&sdev->sdev_gendev);
+ return err;
+}
+EXPORT_SYMBOL_GPL(scsi_dh_set_params);
+
+/*
* scsi_dh_handler_exist - Return TRUE(1) if a device handler exists for
* the given name. FALSE(0) otherwise.
* @name - name of the device handler.
@@ -474,7 +519,6 @@ int scsi_dh_attach(struct request_queue *q, const char *name)
if (!err) {
err = scsi_dh_handler_attach(sdev, scsi_dh);
-
put_device(&sdev->sdev_gendev);
}
return err;
@@ -505,10 +549,8 @@ void scsi_dh_detach(struct request_queue *q)
return;
if (sdev->scsi_dh_data) {
- /* if sdev is not on internal list, detach */
scsi_dh = sdev->scsi_dh_data->scsi_dh;
- if (!device_handler_match(scsi_dh, sdev))
- scsi_dh_handler_detach(sdev, scsi_dh);
+ scsi_dh_handler_detach(sdev, scsi_dh);
}
put_device(&sdev->sdev_gendev);
}