scsi: sd: Remember that READ CAPACITY(16) succeeded
authorMartin K. Petersen <martin.petersen@oracle.com>
Wed, 14 Mar 2018 16:15:56 +0000 (12:15 -0400)
committerMartin K. Petersen <martin.petersen@oracle.com>
Tue, 20 Mar 2018 03:23:04 +0000 (23:23 -0400)
commit597d74005ba85e87c256cd732128ebf7faf54247
treeb40c7e8e2fa4bdc14ba5bdd67d72297947cc2cad
parent09dd15e0d9547ca424de4043bcd429bab6f285c8
scsi: sd: Remember that READ CAPACITY(16) succeeded

The USB storage glue sets the try_rc_10_first flag in an attempt to
avoid wedging poorly implemented legacy USB devices.

If the device capacity is too large to be expressed in the provided
response buffer field of READ CAPACITY(10), a well-behaved device will
set the reported capacity to 0xFFFFFFFF. We will then attempt to issue a
READ CAPACITY(16) to obtain the real capacity.

Since this part of the discovery logic is not covered by the first_scan
flag, a warning will be printed a couple of times times per revalidate
attempt if we upgrade from READ CAPACITY(10) to READ CAPACITY(16).

Remember that we have successfully issued READ CAPACITY(16) so we can
take the fast path on subsequent revalidate attempts.

Reported-by: Menion <menion@gmail.com>
Reviewed-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/scsi/sd.c