From 9447b6ce944b294fa44c9de77b6a4a9fc33aa313 Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Fri, 8 Feb 2019 18:37:25 -0500 Subject: [PATCH] scsi: scsi_debug: Implement support for write protect Teach scsi_debug to honor SWP in the Control Mode Page and report the resulting WP state in the Device-Specific Parameter field. In check_device_access_params() verify that commands that will write the medium are permitted to do so. Signed-off-by: Martin K. Petersen Acked-by: Douglas Gilbert --- drivers/scsi/scsi_debug.c | 76 +++++++++++++++++++---------------------------- 1 file changed, 31 insertions(+), 45 deletions(-) diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 4c9339e..2c25507 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -76,6 +76,7 @@ static const char *sdebug_version_date = "20180128"; #define LBA_OUT_OF_RANGE 0x21 #define INVALID_FIELD_IN_CDB 0x24 #define INVALID_FIELD_IN_PARAM_LIST 0x26 +#define WRITE_PROTECTED 0x27 #define UA_RESET_ASC 0x29 #define UA_CHANGED_ASC 0x2a #define TARGET_CHANGED_ASC 0x3f @@ -668,6 +669,7 @@ static bool sdebug_verbose; static bool have_dif_prot; static bool write_since_sync; static bool sdebug_statistics = DEF_STATISTICS; +static bool sdebug_wp; static unsigned int sdebug_store_sectors; static sector_t sdebug_capacity; /* in sectors */ @@ -2143,9 +2145,11 @@ static int resp_mode_sense(struct scsi_cmnd *scp, target_dev_id = ((devip->sdbg_host->shost->host_no + 1) * 2000) + (devip->target * 1000) - 3; /* for disks set DPOFUA bit and clear write protect (WP) bit */ - if (is_disk) + if (is_disk) { dev_spec = 0x10; /* =0x90 if WP=1 implies read-only */ - else + if (sdebug_wp) + dev_spec |= 0x80; + } else dev_spec = 0x0; if (msense_6) { arr[2] = dev_spec; @@ -2328,6 +2332,10 @@ static int resp_mode_select(struct scsi_cmnd *scp, if (ctrl_m_pg[1] == arr[off + 1]) { memcpy(ctrl_m_pg + 2, arr + off + 2, sizeof(ctrl_m_pg) - 2); + if (ctrl_m_pg[4] & 0x8) + sdebug_wp = true; + else + sdebug_wp = false; sdebug_dsense = !!(ctrl_m_pg[2] & 0x4); goto set_mode_changed_ua; } @@ -2452,8 +2460,8 @@ static int resp_log_sense(struct scsi_cmnd *scp, min(len, SDEBUG_MAX_INQ_ARR_SZ)); } -static int check_device_access_params(struct scsi_cmnd *scp, - unsigned long long lba, unsigned int num) +static inline int check_device_access_params(struct scsi_cmnd *scp, + unsigned long long lba, unsigned int num, bool write) { if (lba + num > sdebug_capacity) { mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0); @@ -2465,6 +2473,10 @@ static int check_device_access_params(struct scsi_cmnd *scp, mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0); return check_condition_result; } + if (write && unlikely(sdebug_wp)) { + mk_sense_buffer(scp, DATA_PROTECT, WRITE_PROTECTED, 0x2); + return check_condition_result; + } return 0; } @@ -2723,18 +2735,9 @@ static int resp_read_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip) } else sqcp = NULL; - /* inline check_device_access_params() */ - if (unlikely(lba + num > sdebug_capacity)) { - mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0); - return check_condition_result; - } - /* transfer length excessive (tie in to block limits VPD page) */ - if (unlikely(num > sdebug_store_sectors)) { - /* needs work to find which cdb byte 'num' comes from */ - mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0); - return check_condition_result; - } - + ret = check_device_access_params(scp, lba, num, false); + if (ret) + return ret; if (unlikely((SDEBUG_OPT_MEDIUM_ERR & sdebug_opts) && (lba <= (sdebug_medium_error_start + sdebug_medium_error_count - 1)) && ((lba + num) > sdebug_medium_error_start))) { @@ -3026,19 +3029,9 @@ static int resp_write_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip) sdev_printk(KERN_ERR, scp->device, "Unprotected WR " "to DIF device\n"); } - - /* inline check_device_access_params() */ - if (unlikely(lba + num > sdebug_capacity)) { - mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0); - return check_condition_result; - } - /* transfer length excessive (tie in to block limits VPD page) */ - if (unlikely(num > sdebug_store_sectors)) { - /* needs work to find which cdb byte 'num' comes from */ - mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0); - return check_condition_result; - } - + ret = check_device_access_params(scp, lba, num, true); + if (ret) + return ret; write_lock_irqsave(&atomic_rw, iflags); /* DIX + T10 DIF */ @@ -3177,7 +3170,7 @@ static int resp_write_scat(struct scsi_cmnd *scp, my_name, __func__, k, lba, num, sg_off); if (num == 0) continue; - ret = check_device_access_params(scp, lba, num); + ret = check_device_access_params(scp, lba, num, true); if (ret) goto err_out_unlock; num_by = num * lb_size; @@ -3261,7 +3254,7 @@ static int resp_write_same(struct scsi_cmnd *scp, u64 lba, u32 num, int ret; u64 lba_off; - ret = check_device_access_params(scp, lba, num); + ret = check_device_access_params(scp, lba, num, true); if (ret) return ret; @@ -3434,18 +3427,9 @@ static int resp_comp_write(struct scsi_cmnd *scp, (cmd[1] & 0xe0) == 0) sdev_printk(KERN_ERR, scp->device, "Unprotected WR " "to DIF device\n"); - - /* inline check_device_access_params() */ - if (lba + num > sdebug_capacity) { - mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0); - return check_condition_result; - } - /* transfer length excessive (tie in to block limits VPD page) */ - if (num > sdebug_store_sectors) { - /* needs work to find which cdb byte 'num' comes from */ - mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0); - return check_condition_result; - } + ret = check_device_access_params(scp, lba, num, false); + if (ret) + return ret; dnum = 2 * num; arr = kcalloc(lb_size, dnum, GFP_ATOMIC); if (NULL == arr) { @@ -3528,7 +3512,7 @@ static int resp_unmap(struct scsi_cmnd *scp, struct sdebug_dev_info *devip) unsigned long long lba = get_unaligned_be64(&desc[i].lba); unsigned int num = get_unaligned_be32(&desc[i].blocks); - ret = check_device_access_params(scp, lba, num); + ret = check_device_access_params(scp, lba, num, true); if (ret) goto out; @@ -3561,7 +3545,7 @@ static int resp_get_lba_status(struct scsi_cmnd *scp, if (alloc_len < 24) return 0; - ret = check_device_access_params(scp, lba, 1); + ret = check_device_access_params(scp, lba, 1, false); if (ret) return ret; @@ -4485,6 +4469,7 @@ module_param_named(virtual_gb, sdebug_virtual_gb, int, S_IRUGO | S_IWUSR); module_param_named(uuid_ctl, sdebug_uuid_ctl, int, S_IRUGO); module_param_named(vpd_use_hostno, sdebug_vpd_use_hostno, int, S_IRUGO | S_IWUSR); +module_param_named(wp, sdebug_wp, bool, S_IRUGO | S_IWUSR); module_param_named(write_same_length, sdebug_write_same_length, int, S_IRUGO | S_IWUSR); @@ -4544,6 +4529,7 @@ MODULE_PARM_DESC(uuid_ctl, "1->use uuid for lu name, 0->don't, 2->all use same (def=0)"); MODULE_PARM_DESC(virtual_gb, "virtual gigabyte (GiB) size (def=0 -> use dev_size_mb)"); MODULE_PARM_DESC(vpd_use_hostno, "0 -> dev ids ignore hostno (def=1 -> unique dev ids)"); +MODULE_PARM_DESC(wp, "Write Protect (def=0)"); MODULE_PARM_DESC(write_same_length, "Maximum blocks per WRITE SAME cmd (def=0xffff)"); #define SDEBUG_INFO_LEN 256 -- 2.7.4