diff options
| author | K. Y. Srinivasan <kys@microsoft.com> | 2014-12-16 13:21:43 -0800 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2015-01-09 15:44:26 +0100 |
| commit | 34a716bc345ba06c34aa33d09536fcb607523818 (patch) | |
| tree | def7a933326d96cb3415c0de1f7b75edeeeba4fe /drivers | |
| parent | 2a09ed3d97ff8b5b377f86da9b9afd9ebd97b362 (diff) | |
storvsc: force discovery of LUNs that may have been removed.
The host asks the guest to scan when a LUN is removed or added.
The only way a guest can identify the removed LUN is when an I/O is
attempted on a removed LUN - the SRB status code indicates that the LUN
is invalid. We currently handle this SRB status and remove the device.
Rather than waiting for an I/O to remove the device, force the discovery of
LUNs that may have been removed prior to discovering LUNs that may have
been added.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Long Li <longli@microsoft.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/scsi/storvsc_drv.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index ab0bb98239b..ae8293a3885 100644 --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -414,10 +414,36 @@ static void storvsc_host_scan(struct work_struct *work) { struct storvsc_scan_work *wrk; struct Scsi_Host *host; + struct scsi_device *sdev; + unsigned long flags; wrk = container_of(work, struct storvsc_scan_work, work); host = wrk->host; + /* + * Before scanning the host, first check to see if any of the + * currrently known devices have been hot removed. We issue a + * "unit ready" command against all currently known devices. + * This I/O will result in an error for devices that have been + * removed. As part of handling the I/O error, we remove the device. + * + * When a LUN is added or removed, the host sends us a signal to + * scan the host. Thus we are forced to discover the LUNs that + * may have been removed this way. + */ + mutex_lock(&host->scan_mutex); + spin_lock_irqsave(host->host_lock, flags); + list_for_each_entry(sdev, &host->__devices, siblings) { + spin_unlock_irqrestore(host->host_lock, flags); + scsi_test_unit_ready(sdev, 1, 1, NULL); + spin_lock_irqsave(host->host_lock, flags); + continue; + } + spin_unlock_irqrestore(host->host_lock, flags); + mutex_unlock(&host->scan_mutex); + /* + * Now scan the host to discover LUNs that may have been added. + */ scsi_scan_host(host); kfree(wrk); |