[PATCH 5/5] scsi_debug: Implement support for DIF Type 2

["Martin K. Petersen" <martin.petersen@oracle.com>]

Add support for 32-byte READ/WRITE as well as DIF Type 2 protection.

Reject protected 10/12/16 byte READ/WRITE commands when Type 2 is
enabled.

Verify Type 2 reference tag according to Expected Initial LBA in 32-byte
CDB.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
---
 drivers/scsi/scsi_debug.c |  135 +++++++++++++++++++++++++++++++++++++--------
 1 files changed, 112 insertions(+), 23 deletions(-)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index fb9af20..f551ec3 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -50,6 +50,7 @@
 #include <scsi/scsi_host.h>
 #include <scsi/scsicam.h>
 #include <scsi/scsi_eh.h>
+#include <scsi/scsi_dbg.h>
 
 #include "sd.h"
 #include "scsi_logging.h"
@@ -64,6 +65,7 @@ static const char * scsi_debug_version_date = "20070104";
 #define PARAMETER_LIST_LENGTH_ERR 0x1a
 #define INVALID_OPCODE 0x20
 #define ADDR_OUT_OF_RANGE 0x21
+#define INVALID_COMMAND_OPCODE 0x20
 #define INVALID_FIELD_IN_CDB 0x24
 #define INVALID_FIELD_IN_PARAM_LIST 0x26
 #define POWERON_RESET 0x29
@@ -180,7 +182,7 @@ static int sdebug_sectors_per;		/* sectors per cylinder */
 #define SDEBUG_SENSE_LEN 32
 
 #define SCSI_DEBUG_CANQUEUE  255
-#define SCSI_DEBUG_MAX_CMD_LEN 16
+#define SCSI_DEBUG_MAX_CMD_LEN 32
 
 struct sdebug_dev_info {
 	struct list_head dev_list;
@@ -296,9 +298,25 @@ static void mk_sense_buffer(struct sdebug_dev_info *devip, int key,
 }
 
 static void get_data_transfer_info(unsigned char *cmd,
-				   unsigned long long *lba, unsigned int *num)
+				   unsigned long long *lba, unsigned int *num,
+				   u32 *ei_lba)
 {
+	*ei_lba = 0;
+
 	switch (*cmd) {
+	case VARIABLE_LENGTH_CMD:
+		*lba = (u64)cmd[19] | (u64)cmd[18] << 8 |
+			(u64)cmd[17] << 16 | (u64)cmd[16] << 24 |
+			(u64)cmd[15] << 32 | (u64)cmd[14] << 40 |
+			(u64)cmd[13] << 48 | (u64)cmd[12] << 56;
+
+		*ei_lba = (u32)cmd[23] | (u32)cmd[22] << 8 |
+			(u32)cmd[21] << 16 | (u32)cmd[20] << 24;
+
+		*num = (u32)cmd[31] | (u32)cmd[30] << 8 | (u32)cmd[29] << 16 |
+			(u32)cmd[28] << 24;
+		break;
+
 	case WRITE_16:
 	case READ_16:
 		*lba = (u64)cmd[9] | (u64)cmd[8] << 8 |
@@ -1589,7 +1607,7 @@ static int do_device_access(struct scsi_cmnd *scmd,
 }
 
 static int prot_verify_read(struct scsi_cmnd *SCpnt, sector_t start_sec,
-			    unsigned int sectors)
+			    unsigned int sectors, u32 ei_lba)
 {
 	unsigned int i, resid;
 	struct scatterlist *psgl;
@@ -1636,13 +1654,23 @@ static int prot_verify_read(struct scsi_cmnd *SCpnt, sector_t start_sec,
 			return 0x01;
 		}
 
-		if (scsi_debug_dif != SD_DIF_TYPE3_PROTECTION &&
+		if (scsi_debug_dif == SD_DIF_TYPE1_PROTECTION &&
 		    be32_to_cpu(sdt[i].ref_tag) != (sector & 0xffffffff)) {
 			printk(KERN_ERR "%s: REF check failed on sector %lu\n",
 			       __func__, (unsigned long)sector);
 			dif_errors++;
 			return 0x03;
 		}
+
+		if (scsi_debug_dif == SD_DIF_TYPE2_PROTECTION &&
+		    be32_to_cpu(sdt[i].ref_tag) != ei_lba) {
+			printk(KERN_ERR "%s: REF check failed on sector %lu\n",
+			       __func__, (unsigned long)sector);
+			dif_errors++;
+			return 0x03;
+		}
+
+		ei_lba++;
 	}
 
 	resid = sectors * 8; /* Bytes of protection data to copy into sgl */
@@ -1670,7 +1698,8 @@ static int prot_verify_read(struct scsi_cmnd *SCpnt, sector_t start_sec,
 }
 
 static int resp_read(struct scsi_cmnd *SCpnt, unsigned long long lba,
-		     unsigned int num, struct sdebug_dev_info *devip)
+		     unsigned int num, struct sdebug_dev_info *devip,
+		     u32 ei_lba)
 {
 	unsigned long iflags;
 	int ret;
@@ -1699,7 +1728,7 @@ static int resp_read(struct scsi_cmnd *SCpnt, unsigned long long lba,
 
 	/* DIX + T10 DIF */
 	if (scsi_debug_dix && scsi_prot_sg_count(SCpnt)) {
-		int prot_ret = prot_verify_read(SCpnt, lba, num);
+		int prot_ret = prot_verify_read(SCpnt, lba, num, ei_lba);
 
 		if (prot_ret) {
 			mk_sense_buffer(devip, ABORTED_COMMAND, 0x10, prot_ret);
@@ -1735,7 +1764,7 @@ void dump_sector(unsigned char *buf, int len)
 }
 
 static int prot_verify_write(struct scsi_cmnd *SCpnt, sector_t start_sec,
-			     unsigned int sectors)
+			     unsigned int sectors, u32 ei_lba)
 {
 	int i, j, ret;
 	struct sd_dif_tuple *sdt;
@@ -1749,11 +1778,6 @@ static int prot_verify_write(struct scsi_cmnd *SCpnt, sector_t start_sec,
 
 	sector = do_div(tmp_sec, sdebug_store_sectors);
 
-	if (((SCpnt->cmnd[1] >> 5) & 7) != 1) {
-		printk(KERN_WARNING "scsi_debug: WRPROTECT != 1\n");
-		return 0;
-	}
-
 	BUG_ON(scsi_sg_count(SCpnt) == 0);
 	BUG_ON(scsi_prot_sg_count(SCpnt) == 0);
 
@@ -1808,7 +1832,7 @@ static int prot_verify_write(struct scsi_cmnd *SCpnt, sector_t start_sec,
 				goto out;
 			}
 
-			if (scsi_debug_dif != SD_DIF_TYPE3_PROTECTION &&
+			if (scsi_debug_dif == SD_DIF_TYPE1_PROTECTION &&
 			    be32_to_cpu(sdt->ref_tag)
 			    != (start_sec & 0xffffffff)) {
 				printk(KERN_ERR
@@ -1819,6 +1843,16 @@ static int prot_verify_write(struct scsi_cmnd *SCpnt, sector_t start_sec,
 				goto out;
 			}
 
+			if (scsi_debug_dif == SD_DIF_TYPE2_PROTECTION &&
+			    be32_to_cpu(sdt->ref_tag) != ei_lba) {
+				printk(KERN_ERR
+				       "%s: REF check failed on sector %lu\n",
+				       __func__, (unsigned long)sector);
+				ret = 0x03;
+				dump_sector(daddr, scsi_debug_sector_size);
+				goto out;
+			}
+
 			/* Would be great to copy this in bigger
 			 * chunks.  However, for the sake of
 			 * correctness we need to verify each sector
@@ -1832,6 +1866,7 @@ static int prot_verify_write(struct scsi_cmnd *SCpnt, sector_t start_sec,
 				sector = 0;	/* Force wrap */
 
 			start_sec++;
+			ei_lba++;
 			daddr += scsi_debug_sector_size;
 			ppage_offset += sizeof(struct sd_dif_tuple);
 		}
@@ -1853,7 +1888,8 @@ out:
 }
 
 static int resp_write(struct scsi_cmnd *SCpnt, unsigned long long lba,
-		      unsigned int num, struct sdebug_dev_info *devip)
+		      unsigned int num, struct sdebug_dev_info *devip,
+		      u32 ei_lba)
 {
 	unsigned long iflags;
 	int ret;
@@ -1864,7 +1900,7 @@ static int resp_write(struct scsi_cmnd *SCpnt, unsigned long long lba,
 
 	/* DIX + T10 DIF */
 	if (scsi_debug_dix && scsi_prot_sg_count(SCpnt)) {
-		int prot_ret = prot_verify_write(SCpnt, lba, num);
+		int prot_ret = prot_verify_write(SCpnt, lba, num, ei_lba);
 
 		if (prot_ret) {
 			mk_sense_buffer(devip, ILLEGAL_REQUEST, 0x10, prot_ret);
@@ -2872,11 +2908,12 @@ static int __init scsi_debug_init(void)
 
 	case SD_DIF_TYPE0_PROTECTION:
 	case SD_DIF_TYPE1_PROTECTION:
+	case SD_DIF_TYPE2_PROTECTION:
 	case SD_DIF_TYPE3_PROTECTION:
 		break;
 
 	default:
-		printk(KERN_ERR "scsi_debug_init: dif must be 0, 1 or 3\n");
+		printk(KERN_ERR "scsi_debug_init: dif must be 0, 1, 2 or 3\n");
 		return -EINVAL;
 	}
 
@@ -3121,6 +3158,7 @@ int scsi_debug_queuecommand(struct scsi_cmnd *SCpnt, done_funct_t done)
 	int len, k;
 	unsigned int num;
 	unsigned long long lba;
+	u32 ei_lba;
 	int errsts = 0;
 	int target = SCpnt->device->id;
 	struct sdebug_dev_info *devip = NULL;
@@ -3254,14 +3292,30 @@ int scsi_debug_queuecommand(struct scsi_cmnd *SCpnt, done_funct_t done)
 	case READ_16:
 	case READ_12:
 	case READ_10:
+		/* READ{10,12,16} and DIF Type 2 are natural enemies */
+		if (scsi_debug_dif == SD_DIF_TYPE2_PROTECTION &&
+		    cmd[1] & 0xe0) {
+			mk_sense_buffer(devip, ILLEGAL_REQUEST,
+					INVALID_COMMAND_OPCODE, 0);
+			errsts = check_condition_result;
+			break;
+		}
+
+		if ((scsi_debug_dif == SD_DIF_TYPE1_PROTECTION ||
+		     scsi_debug_dif == SD_DIF_TYPE3_PROTECTION) &&
+		    (cmd[1] & 0xe0) == 0)
+			printk(KERN_ERR "Unprotected RD/WR to DIF device\n");
+
+		/* fall through */
 	case READ_6:
+read:
 		errsts = check_readiness(SCpnt, 0, devip);
 		if (errsts)
 			break;
 		if (scsi_debug_fake_rw)
 			break;
-		get_data_transfer_info(cmd, &lba, &num);
-		errsts = resp_read(SCpnt, lba, num, devip);
+		get_data_transfer_info(cmd, &lba, &num, &ei_lba);
+		errsts = resp_read(SCpnt, lba, num, devip, ei_lba);
 		if (inj_recovered && (0 == errsts)) {
 			mk_sense_buffer(devip, RECOVERED_ERROR,
 					THRESHOLD_EXCEEDED, 0);
@@ -3288,14 +3342,30 @@ int scsi_debug_queuecommand(struct scsi_cmnd *SCpnt, done_funct_t done)
 	case WRITE_16:
 	case WRITE_12:
 	case WRITE_10:
+		/* WRITE{10,12,16} and DIF Type 2 are natural enemies */
+		if (scsi_debug_dif == SD_DIF_TYPE2_PROTECTION &&
+		    cmd[1] & 0xe0) {
+			mk_sense_buffer(devip, ILLEGAL_REQUEST,
+					INVALID_COMMAND_OPCODE, 0);
+			errsts = check_condition_result;
+			break;
+		}
+
+		if ((scsi_debug_dif == SD_DIF_TYPE1_PROTECTION ||
+		     scsi_debug_dif == SD_DIF_TYPE3_PROTECTION) &&
+		    (cmd[1] & 0xe0) == 0)
+			printk(KERN_ERR "Unprotected RD/WR to DIF device\n");
+
+		/* fall through */
 	case WRITE_6:
+write:
 		errsts = check_readiness(SCpnt, 0, devip);
 		if (errsts)
 			break;
 		if (scsi_debug_fake_rw)
 			break;
-		get_data_transfer_info(cmd, &lba, &num);
-		errsts = resp_write(SCpnt, lba, num, devip);
+		get_data_transfer_info(cmd, &lba, &num, &ei_lba);
+		errsts = resp_write(SCpnt, lba, num, devip, ei_lba);
 		if (inj_recovered && (0 == errsts)) {
 			mk_sense_buffer(devip, RECOVERED_ERROR,
 					THRESHOLD_EXCEEDED, 0);
@@ -3341,15 +3411,34 @@ int scsi_debug_queuecommand(struct scsi_cmnd *SCpnt, done_funct_t done)
 			break;
 		if (scsi_debug_fake_rw)
 			break;
-		get_data_transfer_info(cmd, &lba, &num);
-		errsts = resp_read(SCpnt, lba, num, devip);
+		get_data_transfer_info(cmd, &lba, &num, &ei_lba);
+		errsts = resp_read(SCpnt, lba, num, devip, ei_lba);
 		if (errsts)
 			break;
-		errsts = resp_write(SCpnt, lba, num, devip);
+		errsts = resp_write(SCpnt, lba, num, devip, ei_lba);
 		if (errsts)
 			break;
 		errsts = resp_xdwriteread(SCpnt, lba, num, devip);
 		break;
+	case VARIABLE_LENGTH_CMD:
+		if (scsi_debug_dif == SD_DIF_TYPE2_PROTECTION) {
+
+			if ((cmd[10] & 0xe0) == 0)
+				printk(KERN_ERR
+				       "Unprotected RD/WR to DIF device\n");
+
+			if (cmd[9] == READ_32)
+				goto read;
+
+			if (cmd[9] == WRITE_32)
+				goto write;
+		}
+
+		mk_sense_buffer(devip, ILLEGAL_REQUEST,
+				INVALID_FIELD_IN_CDB, 0);
+		errsts = check_condition_result;
+		break;
+
 	default:
 		if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
 			printk(KERN_INFO "scsi_debug: Opcode: 0x%x not "
-- 
1.6.0.6