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authorHannes Reinecke <hare@suse.de>2014-06-25 15:27:39 +0200
committerChristoph Hellwig <hch@lst.de>2014-07-17 22:07:39 +0200
commitd9e5d6183715e691b37afd3785c311d05cd1338d (patch)
treeb7b85fb5f76d647fe128972dadfe0157c8703478 /drivers/scsi/scsi_scan.c
parent1abf635d2f3332641570e1913e317073834a055f (diff)
scsi_scan: Fixup scsilun_to_int()
scsilun_to_int() has an error which prevents it from generating correct LUN numbers for 64bit values. Also we should remove the misleading comment about portions of the LUN being ignored; the initiator should treat the LUN as an opaque value. And, finally, the example given should use the correct prefix (here: extended flat space addressing scheme). This patch includes the modifications suggested by Bart van Assche. Cc: Bart van Assche <bvanassche@acm.org> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: James Bottomley <jbottomley@parallels.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'drivers/scsi/scsi_scan.c')
-rw-r--r--drivers/scsi/scsi_scan.c22
1 files changed, 10 insertions, 12 deletions
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index fa57a046f025..784d4e648cf5 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -1263,14 +1263,15 @@ static void scsi_sequential_lun_scan(struct scsi_target *starget,
* truncation before using this function.
*
* Notes:
- * The struct scsi_lun is assumed to be four levels, with each level
- * effectively containing a SCSI byte-ordered (big endian) short; the
- * addressing bits of each level are ignored (the highest two bits).
* For a description of the LUN format, post SCSI-3 see the SCSI
* Architecture Model, for SCSI-3 see the SCSI Controller Commands.
*
- * Given a struct scsi_lun of: 0a 04 0b 03 00 00 00 00, this function returns
- * the integer: 0x0b030a04
+ * Given a struct scsi_lun of: d2 04 0b 03 00 00 00 00, this function
+ * returns the integer: 0x0b03d204
+ *
+ * This encoding will return a standard integer LUN for LUNs smaller
+ * than 256, which typically use a single level LUN structure with
+ * addressing method 0.
**/
u64 scsilun_to_int(struct scsi_lun *scsilun)
{
@@ -1279,8 +1280,8 @@ u64 scsilun_to_int(struct scsi_lun *scsilun)
lun = 0;
for (i = 0; i < sizeof(lun); i += 2)
- lun = lun | (((scsilun->scsi_lun[i] << 8) |
- scsilun->scsi_lun[i + 1]) << (i * 8));
+ lun = lun | (((u64)scsilun->scsi_lun[i] << ((i + 1) * 8)) |
+ ((u64)scsilun->scsi_lun[i + 1] << (i * 8)));
return lun;
}
EXPORT_SYMBOL(scsilun_to_int);
@@ -1294,13 +1295,10 @@ EXPORT_SYMBOL(scsilun_to_int);
* Reverts the functionality of the scsilun_to_int, which packed
* an 8-byte lun value into an int. This routine unpacks the int
* back into the lun value.
- * Note: the scsilun_to_int() routine does not truly handle all
- * 8bytes of the lun value. This functions restores only as much
- * as was set by the routine.
*
* Notes:
- * Given an integer : 0x0b030a04, this function returns a
- * scsi_lun of : struct scsi_lun of: 0a 04 0b 03 00 00 00 00
+ * Given an integer : 0x0b03d204, this function returns a
+ * struct scsi_lun of: d2 04 0b 03 00 00 00 00
*
**/
void int_to_scsilun(u64 lun, struct scsi_lun *scsilun)