To prevent random utility reads and writes of the diag interface to the
chip, we first require a handshake of reading from offset 0 and writing
to offset 0 before any other reads or writes can be done through the
diags device. Otherwise chip errors can be triggered.
Signed-off-by: Dave Olson <dave.olson@qlogic.com>
Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diag_set_link = 0;
ret = 0;
diag_set_link = 0;
ret = 0;
else if ((count % 4) || (*off % 4))
/* address or length is not 32-bit aligned, hence invalid */
ret = -EINVAL;
else if ((count % 4) || (*off % 4))
/* address or length is not 32-bit aligned, hence invalid */
ret = -EINVAL;
+ else if (ipath_diag_inuse < 1 && (*off || count != 8))
+ ret = -EINVAL; /* prevent cat /dev/ipath_diag* */
else if ((count % 8) || (*off % 8))
/* address or length not 64-bit aligned; do 32-bit reads */
ret = ipath_read_umem32(dd, data, kreg_base + *off, count);
else if ((count % 8) || (*off % 8))
/* address or length not 64-bit aligned; do 32-bit reads */
ret = ipath_read_umem32(dd, data, kreg_base + *off, count);
if (ret >= 0) {
*off += count;
ret = count;
if (ret >= 0) {
*off += count;
ret = count;
+ if (ipath_diag_inuse == -2)
+ ipath_diag_inuse++;
else if ((count % 4) || (*off % 4))
/* address or length is not 32-bit aligned, hence invalid */
ret = -EINVAL;
else if ((count % 4) || (*off % 4))
/* address or length is not 32-bit aligned, hence invalid */
ret = -EINVAL;
+ else if ((ipath_diag_inuse == -1 && (*off || count != 8)) ||
+ ipath_diag_inuse == -2) /* read qw off 0, write qw off 0 */
+ ret = -EINVAL; /* before any other write allowed */
else if ((count % 8) || (*off % 8))
/* address or length not 64-bit aligned; do 32-bit writes */
ret = ipath_write_umem32(dd, kreg_base + *off, data, count);
else if ((count % 8) || (*off % 8))
/* address or length not 64-bit aligned; do 32-bit writes */
ret = ipath_write_umem32(dd, kreg_base + *off, data, count);
if (ret >= 0) {
*off += count;
ret = count;
if (ret >= 0) {
*off += count;
ret = count;
+ if (ipath_diag_inuse == -1)
+ ipath_diag_inuse = 1; /* all read/write OK now */