scsi: mark expected switch fall-throughs

PATCH In review Gustavo A. R. Silva 2 participants 5 messages Oct 3, 2018 – Oct 16, 2018 1 message not in the archive

Subsystems (5)

SCSI SCSI tape driver Hewlett-packard smart array RAID driver (hpsa) IBM ServeRAID RAID driver +1 more subsystems

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Gustavo A. R. Silva

author

2018-10-03 14:55 UTC #0 lore raw

PATCH 1/1 scsi: mark expected switch fall-throughs

In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through.

Addresses-Coverity-ID: 1195463 ("Missing break in switch")
Addresses-Coverity-ID: 1195464 ("Missing break in switch")
Addresses-Coverity-ID: 1195465 ("Missing break in switch")
Addresses-Coverity-ID: 1195466 ("Missing break in switch")
Addresses-Coverity-ID: 1357338 ("Missing break in switch")
Addresses-Coverity-ID: 114973 ("Missing break in switch")
Addresses-Coverity-ID: 114983 ("Missing break in switch")
Addresses-Coverity-ID: 114984 ("Missing break in switch")
Addresses-Coverity-ID: 114985 ("Missing break in switch")
Addresses-Coverity-ID: 114988 ("Missing break in switch")
Addresses-Coverity-ID: 114994 ("Missing break in switch")
Addresses-Coverity-ID: 114995 ("Missing break in switch")

Signed-off-by Gustavo A. R. Silva <[email protected]>

---
 drivers/scsi/hpsa.c | 5 +++++
 drivers/scsi/ips.c  | 1 +
 drivers/scsi/osst.c | 6 ++++++
 drivers/scsi/ppa.c  | 1 +
 drivers/scsi/st.c   | 4 ++++
 5 files changed, 17 insertions(+)

drivers/scsi/hpsa.c +5 -0

index f903983..fb6a356 100644
@@ -4662,6 +4662,7 @@ static int fixup_ioaccel_cdb(u8 *cdb, int *cdb_len)
 	case WRITE_6:
 	case WRITE_12:
 		is_write = 1;
+		/* fall through */
 	case READ_6:
 	case READ_12:
 		if (*cdb_len == 6) {

@@ -5092,6 +5093,7 @@ static int hpsa_scsi_ioaccel_raid_map(struct ctlr_info *h,
 	switch (cmd->cmnd[0]) {
 	case WRITE_6:
 		is_write = 1;
+		/* fall through */
 	case READ_6:
 		first_block = (((cmd->cmnd[1] & 0x1F) << 16) |
 				(cmd->cmnd[2] << 8) |

@@ -5102,6 +5104,7 @@ static int hpsa_scsi_ioaccel_raid_map(struct ctlr_info *h,
 		break;
 	case WRITE_10:
 		is_write = 1;
+		/* fall through */
 	case READ_10:
 		first_block =
 			(((u64) cmd->cmnd[2]) << 24) |

@@ -5114,6 +5117,7 @@ static int hpsa_scsi_ioaccel_raid_map(struct ctlr_info *h,
 		break;
 	case WRITE_12:
 		is_write = 1;
+		/* fall through */
 	case READ_12:
 		first_block =
 			(((u64) cmd->cmnd[2]) << 24) |

@@ -5128,6 +5132,7 @@ static int hpsa_scsi_ioaccel_raid_map(struct ctlr_info *h,
 		break;
 	case WRITE_16:
 		is_write = 1;
+		/* fall through */
 	case READ_16:
 		first_block =
 			(((u64) cmd->cmnd[2]) << 56) |

drivers/scsi/ips.c +1 -0

index bd6ac6b..8e1c45d 100644
@@ -3485,6 +3485,7 @@ ips_send_cmd(ips_ha_t * ha, ips_scb_t * scb)
 
 		case START_STOP:
 			scb->scsi_cmd->result = DID_OK << 16;
+			/* fall through */
 
 		case TEST_UNIT_READY:
 		case INQUIRY:

drivers/scsi/osst.c +6 -0

index 7a1a1ed..8af608d 100644
@@ -216,12 +216,14 @@ static void osst_analyze_sense(struct osst_request *SRpnt, struct st_cmdstatus *
 		switch (sense[0] & 0x7f) {
 		case 0x71:
 			s->deferred = 1;
+			/* fall through */
 		case 0x70:
 			s->fixed_format = 1;
 			s->flags = sense[2] & 0xe0;
 			break;
 		case 0x73:
 			s->deferred = 1;
+			/* fall through */
 		case 0x72:
 			s->fixed_format = 0;
 			ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);

@@ -591,6 +593,7 @@ static void osst_init_aux(struct osst_tape * STp, int frame_type, int frame_seq_
 		dat->dat_list[0].flags    = frame_type==OS_FRAME_TYPE_MARKER?
 							OS_DAT_FLAGS_MARK:OS_DAT_FLAGS_DATA;
 		dat->dat_list[0].reserved = 0;
+		/* fall through */
 	  case	OS_FRAME_TYPE_EOD:
 		aux->update_frame_cntr    = htonl(0);
 		par->partition_num        = OS_DATA_PARTITION;

@@ -4086,6 +4089,7 @@ static int osst_int_ioctl(struct osst_tape * STp, struct osst_request ** aSRpnt,
 	switch (cmd_in) {
 	 case MTFSFM:
 		chg_eof = 0; /* Changed from the FSF after this */
+		/* fall through */
 	 case MTFSF:
 		if (STp->raw)
 		   return (-EIO);

@@ -4101,6 +4105,7 @@ static int osst_int_ioctl(struct osst_tape * STp, struct osst_request ** aSRpnt,
 
 	 case MTBSF:
 		chg_eof = 0; /* Changed from the FSF after this */
+		/* fall through */
 	 case MTBSFM:
 		if (STp->raw)
 		   return (-EIO);

@@ -4312,6 +4317,7 @@ static int osst_int_ioctl(struct osst_tape * STp, struct osst_request ** aSRpnt,
 					   name, STp->block_size);
 			 return 0;
 		 }
+		/* fall through */
 	 case MTSETDENSITY:       /* Set tape density */
 	 case MTSETDRVBUFFER:     /* Set drive buffering */
 	 case SET_DENS_AND_BLK:   /* Set density and block size */

drivers/scsi/ppa.c +1 -0

index ee86a0c..d29999b 100644
@@ -717,6 +717,7 @@ static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd)
 			}
 			cmd->SCp.phase++;
 		}
+		/* fall through */
 
 	case 2:		/* Phase 2 - We are now talking to the scsi bus */
 		if (!ppa_select(dev, scmd_id(cmd))) {

drivers/scsi/st.c +4 -0

index 307df2f..f1351ec 100644
@@ -337,12 +337,14 @@ static void st_analyze_sense(struct st_request *SRpnt, struct st_cmdstatus *s)
 		switch (sense[0] & 0x7f) {
 		case 0x71:
 			s->deferred = 1;
+			/* fall through */
 		case 0x70:
 			s->fixed_format = 1;
 			s->flags = sense[2] & 0xe0;
 			break;
 		case 0x73:
 			s->deferred = 1;
+			/* fall through */
 		case 0x72:
 			s->fixed_format = 0;
 			ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);

@@ -2721,6 +2723,7 @@ static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned lon
 	switch (cmd_in) {
 	case MTFSFM:
 		chg_eof = 0;	/* Changed from the FSF after this */
+		/* fall through */
 	case MTFSF:
 		cmd[0] = SPACE;
 		cmd[1] = 0x01;	/* Space FileMarks */

@@ -2735,6 +2738,7 @@ static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned lon
 		break;
 	case MTBSFM:
 		chg_eof = 0;	/* Changed from the FSF after this */
+		/* fall through */
 	case MTBSF:
 		cmd[0] = SPACE;
 		cmd[1] = 0x01;	/* Space FileMarks */

Signature · 1 line

2.7.4

A message that is not in the archive (sent off-list or not yet received): BYAPR11MB2855F7449E2A15FDB28EC5B7E1E90@BYAPR11MB2855.namprd11.prod.outlook.com

Gustavo A. R. Silva

author

2018-10-03 15:47 UTC #2 lore raw

Quoted 67 lines · On 10/3/18 5:44 PM, [email protected] wrote:

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
*From:*Gustavo A. R. Silva <[email protected]>
*Sent:* Wednesday, October 3, 2018 9:55 AM
*To:* Don Brace; James E.J. Bottomley; Martin K. Petersen; Adaptec OEM Raid Solutions; Willem Riede; Kai Mäkisara
*Cc:* [email protected]; [email protected]; [email protected]; [email protected]; Gustavo A. R. Silva *Subject:* [PATCH] scsi: mark expected switch fall-throughs
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through.
Signed-off-by Gustavo A. R. Silva <[email protected]>
---
drivers/scsi/hpsa.c | 5 +++++
drivers/scsi/ips.c | 1 +
drivers/scsi/osst.c | 6 ++++++
drivers/scsi/ppa.c | 1 +
drivers/scsi/st.c | 4 ++++
 5 files changed, 17 insertions(+)
drivers/scsi/hpsa.c +0 -0
index f903983..fb6a356 100644
@@ -4662,6 +4662,7 @@ static int fixup_ioaccel_cdb(u8 *cdb, int *cdb_len)
        case WRITE_6:
        case WRITE_12:
                is_write = 1;
+               /* fall through */
        case READ_6:
        case READ_12:
                if (*cdb_len == 6) {
drivers/scsi/hpsa.c +0 -0
@@ -5092,6 +5093,7 @@ static int hpsa_scsi_ioaccel_raid_map(struct ctlr_info *h,
         switch (cmd->cmnd[0]) {
        case WRITE_6:
                is_write = 1;
+               /* fall through */
        case READ_6:
                first_block = (((cmd->cmnd[1] & 0x1F) << 16) | (cmd->cmnd[2] << 8) |
drivers/scsi/hpsa.c +0 -0
@@ -5102,6 +5104,7 @@ static int hpsa_scsi_ioaccel_raid_map(struct ctlr_info *h,
                 break;
        case WRITE_10:
                is_write = 1;
+               /* fall through */
        case READ_10:
                first_block =
                        (((u64) cmd->cmnd[2]) << 24) |
drivers/scsi/hpsa.c +0 -0
@@ -5114,6 +5117,7 @@ static int hpsa_scsi_ioaccel_raid_map(struct ctlr_info *h,
                 break;
        case WRITE_12:
                is_write = 1;
+               /* fall through */
        case READ_12:
                first_block =
                        (((u64) cmd->cmnd[2]) << 24) |
drivers/scsi/hpsa.c +0 -0
@@ -5128,6 +5132,7 @@ static int hpsa_scsi_ioaccel_raid_map(struct ctlr_info *h,
                 break;
        case WRITE_16:
                is_write = 1;
+               /* fall through */
        case READ_16:
                first_block =
                        (((u64) cmd->cmnd[2]) << 56) |

Quoted 5 lines

Tested-by Don Brace <[email protected]>
Acked-by Don Brace <[email protected]>

Thanks for this, but please don't remove the Coverity tags.

--
Gustavo

Martin K. Petersen

2018-10-11 02:47 UTC #3 lore raw

In reply to Gustavo A. R. Silva

Hi Gustavo,

Quoted 2 lines

In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through.

I'm not entirely convinced that all these identified fall through cases are intentional. From a quick glance, some of them look like bugs...

Quoted 12 lines

drivers/scsi/ips.c +1 -0

index bd6ac6b..8e1c45d 100644
@@ -3485,6 +3485,7 @@ ips_send_cmd(ips_ha_t * ha, ips_scb_t * scb)
 
 		case START_STOP:
 			scb->scsi_cmd->result = DID_OK << 16;
+			/* fall through */
 
 		case TEST_UNIT_READY:
 		case INQUIRY:

Signature · 1 line

Martin K. Petersen	Oracle Linux Engineering

Gustavo A. R. Silva

author

2018-10-12 12:26 UTC #4 lore raw

Hi Martin,

Quoted 9 lines · Martin K. Petersen

Hi Gustavo,
Quoted 2 lines
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through.
I'm not entirely convinced that all these identified fall through cases are intentional. From a quick glance, some of them look like bugs...

I took a second look at this and, certainly, the one below looks more like a bug. The rest seem to be false positives.

Also, notice that this code has been there since 2005. So, that's why I was inclined to think that all of them are false positives.

Quoted 9 lines

drivers/scsi/ips.c ips_send_cmd(ips_ha_t * ha, ips_scb_t * scb) · line 3488
Quoted 9 lines
drivers/scsi/ips.c +1 -0
index bd6ac6b..8e1c45d 100644
@@ -3485,6 +3485,7 @@ ips_send_cmd(ips_ha_t * ha, ips_scb_t * scb)
 
 		case START_STOP:
 			scb->scsi_cmd->result = DID_OK << 16;
+			/* fall through */

If you confirm this is an actual bug, I can send a separate fix.

Quoted 4 lines

drivers/scsi/ips.c ips_send_cmd(ips_ha_t * ha, ips_scb_t * scb) · line 3491
Quoted 3 lines
drivers/scsi/ips.c +0 -0
 		case TEST_UNIT_READY:
 		case INQUIRY:

Thanks for the feedback.
--
Gustavo

Martin K. Petersen

2018-10-16 02:47 UTC #5 lore raw

Gustavo,

Quoted 5 lines

Quoted 2 lines
I'm not entirely convinced that all these identified fall through cases are intentional. From a quick glance, some of them look like bugs...
I took a second look at this and, certainly, the one below looks more like a bug. The rest seem to be false positives.

Yep.

Quoted 11 lines

Quoted 9 lines
drivers/scsi/ips.c ips_send_cmd(ips_ha_t * ha, ips_scb_t * scb) · line 3488
Quoted 9 lines
drivers/scsi/ips.c +1 -0
index bd6ac6b..8e1c45d 100644
@@ -3485,6 +3485,7 @@ ips_send_cmd(ips_ha_t * ha, ips_scb_t * scb)
 
 		case START_STOP:
 			scb->scsi_cmd->result = DID_OK << 16;
+			/* fall through */
If you confirm this is an actual bug, I can send a separate fix.

I believe it is. So please do.

Signature · 1 line

Martin K. Petersen	Oracle Linux Engineering