libata: fix bug with non-ncq devices

The recent commit 2fca5ccf97d2c28bcfce44f5b07d85e74e3cd18e ("libata:
switch to using block layer tagging support") to enable support for
block layer tagging in libata was broken for non-NCQ devices

The block layer initializes the tag field to -1 to detect invalid uses
of a tag, and if the libata devices does NOT support NCQ, we just used
that field to index the internal command list.  So we need to check for
-1 first and only use the tag field if it's valid.

Signed-off-by: Jens Axboe <[email protected]>
Reported-by: Alexander Beregalov <[email protected]>
Tested-by: Paul Mundt <[email protected]>
Tested-by: Dave Young <[email protected]>
Tested-by: Rafael J. Wysocki <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions