diff options
Diffstat (limited to 'drivers/scsi/scsi.c')
| -rw-r--r-- | drivers/scsi/scsi.c | 171 |
1 files changed, 162 insertions, 9 deletions
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index 09ef0b31dfc0..c4bf99a842f3 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -504,18 +504,22 @@ void scsi_attach_vpd(struct scsi_device *sdev) } /** - * scsi_report_opcode - Find out if a given command opcode is supported + * scsi_report_opcode - Find out if a given command is supported * @sdev: scsi device to query * @buffer: scratch buffer (must be at least 20 bytes long) * @len: length of buffer - * @opcode: opcode for command to look up - * - * Uses the REPORT SUPPORTED OPERATION CODES to look up the given - * opcode. Returns -EINVAL if RSOC fails, 0 if the command opcode is - * unsupported and 1 if the device claims to support the command. + * @opcode: opcode for the command to look up + * @sa: service action for the command to look up + * + * Uses the REPORT SUPPORTED OPERATION CODES to check support for the + * command identified with @opcode and @sa. If the command does not + * have a service action, @sa must be 0. Returns -EINVAL if RSOC fails, + * 0 if the command is not supported and 1 if the device claims to + * support the command. */ int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer, - unsigned int len, unsigned char opcode) + unsigned int len, unsigned char opcode, + unsigned short sa) { unsigned char cmd[16]; struct scsi_sense_hdr sshdr; @@ -539,8 +543,14 @@ int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer, memset(cmd, 0, 16); cmd[0] = MAINTENANCE_IN; cmd[1] = MI_REPORT_SUPPORTED_OPERATION_CODES; - cmd[2] = 1; /* One command format */ - cmd[3] = opcode; + if (!sa) { + cmd[2] = 1; /* One command format */ + cmd[3] = opcode; + } else { + cmd[2] = 3; /* One command format with service action */ + cmd[3] = opcode; + put_unaligned_be16(sa, &cmd[4]); + } put_unaligned_be32(request_len, &cmd[6]); memset(buffer, 0, len); @@ -560,6 +570,149 @@ int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer, } EXPORT_SYMBOL(scsi_report_opcode); +#define SCSI_CDL_CHECK_BUF_LEN 64 + +static bool scsi_cdl_check_cmd(struct scsi_device *sdev, u8 opcode, u16 sa, + unsigned char *buf) +{ + int ret; + u8 cdlp; + + /* Check operation code */ + ret = scsi_report_opcode(sdev, buf, SCSI_CDL_CHECK_BUF_LEN, opcode, sa); + if (ret <= 0) + return false; + + if ((buf[1] & 0x03) != 0x03) + return false; + + /* See SPC-6, one command format of REPORT SUPPORTED OPERATION CODES */ + cdlp = (buf[1] & 0x18) >> 3; + if (buf[0] & 0x01) { + /* rwcdlp == 1 */ + switch (cdlp) { + case 0x01: + /* T2A page */ + return true; + case 0x02: + /* T2B page */ + return true; + } + } else { + /* rwcdlp == 0 */ + switch (cdlp) { + case 0x01: + /* A page */ + return true; + case 0x02: + /* B page */ + return true; + } + } + + return false; +} + +/** + * scsi_cdl_check - Check if a SCSI device supports Command Duration Limits + * @sdev: The device to check + */ +void scsi_cdl_check(struct scsi_device *sdev) +{ + bool cdl_supported; + unsigned char *buf; + + buf = kmalloc(SCSI_CDL_CHECK_BUF_LEN, GFP_KERNEL); + if (!buf) { + sdev->cdl_supported = 0; + return; + } + + /* Check support for READ_16, WRITE_16, READ_32 and WRITE_32 commands */ + cdl_supported = + scsi_cdl_check_cmd(sdev, READ_16, 0, buf) || + scsi_cdl_check_cmd(sdev, WRITE_16, 0, buf) || + scsi_cdl_check_cmd(sdev, VARIABLE_LENGTH_CMD, READ_32, buf) || + scsi_cdl_check_cmd(sdev, VARIABLE_LENGTH_CMD, WRITE_32, buf); + if (cdl_supported) { + /* + * We have CDL support: force the use of READ16/WRITE16. + * READ32 and WRITE32 will be used for devices that support + * the T10_PI_TYPE2_PROTECTION protection type. + */ + sdev->use_16_for_rw = 1; + sdev->use_10_for_rw = 0; + + sdev->cdl_supported = 1; + } else { + sdev->cdl_supported = 0; + } + + kfree(buf); +} + +/** + * scsi_cdl_enable - Enable or disable a SCSI device supports for Command + * Duration Limits + * @sdev: The target device + * @enable: the target state + */ +int scsi_cdl_enable(struct scsi_device *sdev, bool enable) +{ + struct scsi_mode_data data; + struct scsi_sense_hdr sshdr; + struct scsi_vpd *vpd; + bool is_ata = false; + char buf[64]; + int ret; + + if (!sdev->cdl_supported) + return -EOPNOTSUPP; + + rcu_read_lock(); + vpd = rcu_dereference(sdev->vpd_pg89); + if (vpd) + is_ata = true; + rcu_read_unlock(); + + /* + * For ATA devices, CDL needs to be enabled with a SET FEATURES command. + */ + if (is_ata) { + char *buf_data; + int len; + + ret = scsi_mode_sense(sdev, 0x08, 0x0a, 0xf2, buf, sizeof(buf), + 5 * HZ, 3, &data, NULL); + if (ret) + return -EINVAL; + + /* Enable CDL using the ATA feature page */ + len = min_t(size_t, sizeof(buf), + data.length - data.header_length - + data.block_descriptor_length); + buf_data = buf + data.header_length + + data.block_descriptor_length; + if (enable) + buf_data[4] = 0x02; + else + buf_data[4] = 0; + + ret = scsi_mode_select(sdev, 1, 0, buf_data, len, 5 * HZ, 3, + &data, &sshdr); + if (ret) { + if (scsi_sense_valid(&sshdr)) + scsi_print_sense_hdr(sdev, + dev_name(&sdev->sdev_gendev), &sshdr); + return ret; + } + } + + sdev->cdl_enable = enable; + + return 0; +} + /** * scsi_device_get - get an additional reference to a scsi_device * @sdev: device to get a reference to |