From: Hannes Reinecke Date: Wed, 25 Jun 2014 13:27:39 +0000 (+0200) Subject: scsi_scan: Fixup scsilun_to_int() X-Git-Tag: firefly_0821_release~176^2~3376^2~119 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d9e5d6183715e691b37afd3785c311d05cd1338d;p=firefly-linux-kernel-4.4.55.git 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 Cc: Christoph Hellwig Signed-off-by: Hannes Reinecke Reviewed-by: James Bottomley Signed-off-by: Christoph Hellwig --- 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)