diff options
Diffstat (limited to 'drivers/target/target_core_spc.c')
| -rw-r--r-- | drivers/target/target_core_spc.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/target/target_core_spc.c b/drivers/target/target_core_spc.c index 9413e1a949e5..0aa47babd16c 100644 --- a/drivers/target/target_core_spc.c +++ b/drivers/target/target_core_spc.c @@ -635,6 +635,18 @@ spc_emulate_evpd_b2(struct se_cmd *cmd, unsigned char *buf) if (dev->dev_attrib.emulate_tpws != 0) buf[5] |= 0x40 | 0x20; + /* + * The unmap_zeroes_data set means that the underlying device supports + * REQ_DISCARD and has the discard_zeroes_data bit set. This satisfies + * the SBC requirements for LBPRZ, meaning that a subsequent read + * will return zeroes after an UNMAP or WRITE SAME (16) to an LBA + * See sbc4r36 6.6.4. + */ + if (((dev->dev_attrib.emulate_tpu != 0) || + (dev->dev_attrib.emulate_tpws != 0)) && + (dev->dev_attrib.unmap_zeroes_data != 0)) + buf[5] |= 0x04; + return 0; } |