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authorBart Van Assche2017-06-02 23:21:55 +0200
committerMartin K. Petersen2017-06-13 02:55:59 +0200
commit0db6ca8a5e1ea585795db3643ec7d50fc8cb1aff (patch)
tree52ae689dcddbc9155a840617c405de2b377de618 /include/scsi/scsi_device.h
parentscsi: Create two versions of scsi_internal_device_unblock() (diff)
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scsi: Protect SCSI device state changes with a mutex
Serializing SCSI device state changes avoids that two state changes can occur concurrently, e.g. the state changes in scsi_target_block() and __scsi_remove_device(). This serialization is essential to make patch "Make __scsi_remove_device go straight from BLOCKED to DEL" work reliably. Enable this mechanism for all scsi_target_*block() callers but not for the scsi_internal_device_unblock() calls from the mpt3sas driver because that driver can call scsi_internal_device_unblock() from atomic context. Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Hannes Reinecke <hare@suse.com> Cc: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'include/scsi/scsi_device.h')
-rw-r--r--include/scsi/scsi_device.h1
1 files changed, 1 insertions, 0 deletions
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 5f24dae2a8e1..d13bc80825b1 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -207,6 +207,7 @@ struct scsi_device {
void *handler_data;
unsigned char access_state;
+ struct mutex state_mutex;
enum scsi_device_state sdev_state;
unsigned long sdev_data[0];
} __attribute__((aligned(sizeof(unsigned long))));