[SCSI] aacraid: SCSI dma mapping failure case handling

This patch handles SCSI dma mapping failure case. Reporting error code to the
upper layer instead of BUG_ON().

Signed-off-by: Mahesh Rajashekhara <[e-mail]>
Reviewed-by: Tomas Henzl <[e-mail]>
Signed-off-by: James Bottomley <[e-mail]>

drivers/scsi/aacraid/aachba.c

···
  *              M O D U L E   G L O B A L S
  */
 
-static unsigned long aac_build_sg(struct scsi_cmnd* scsicmd, struct sgmap* sgmap);
-static unsigned long aac_build_sg64(struct scsi_cmnd* scsicmd, struct sgmap64* psg);
-static unsigned long aac_build_sgraw(struct scsi_cmnd* scsicmd, struct sgmapraw* psg);
-static unsigned long aac_build_sgraw2(struct scsi_cmnd *scsicmd, struct aac_raw_io2 *rio2, int sg_max);
-static int aac_convert_sgraw2(struct aac_raw_io2 *rio2, int pages, int nseg, int nseg_new);
+static long aac_build_sg(struct scsi_cmnd *scsicmd, struct sgmap *sgmap);
+static long aac_build_sg64(struct scsi_cmnd *scsicmd, struct sgmap64 *psg);
+static long aac_build_sgraw(struct scsi_cmnd *scsicmd, struct sgmapraw *psg);
+static long aac_build_sgraw2(struct scsi_cmnd *scsicmd,
+				struct aac_raw_io2 *rio2, int sg_max);
+static int aac_convert_sgraw2(struct aac_raw_io2 *rio2,
+				int pages, int nseg, int nseg_new);
 static int aac_send_srb_fib(struct scsi_cmnd* scsicmd);
 #ifdef AAC_DETAILED_STATUS_INFO
 static char *aac_get_status_string(u32 status);
···
 {
 	struct aac_dev *dev = fib->dev;
 	u16 fibsize, command;
+	long ret;
 
 	aac_fib_init(fib);
 	if (dev->comm_interface == AAC_COMM_MESSAGE_TYPE2 && !dev->sync_mode) {
···
 		readcmd2->byteCount = cpu_to_le32(count<<9);
 		readcmd2->cid = cpu_to_le16(scmd_id(cmd));
 		readcmd2->flags = cpu_to_le16(RIO2_IO_TYPE_READ);
-		aac_build_sgraw2(cmd, readcmd2, dev->scsi_host_ptr->sg_tablesize);
+		ret = aac_build_sgraw2(cmd, readcmd2,
+				dev->scsi_host_ptr->sg_tablesize);
+		if (ret < 0)
+			return ret;
 		command = ContainerRawIo2;
 		fibsize = sizeof(struct aac_raw_io2) +
 			((le32_to_cpu(readcmd2->sgeCnt)-1) * sizeof(struct sge_ieee1212));
···
 		readcmd->flags = cpu_to_le16(RIO_TYPE_READ);
 		readcmd->bpTotal = 0;
 		readcmd->bpComplete = 0;
-		aac_build_sgraw(cmd, &readcmd->sg);
+		ret = aac_build_sgraw(cmd, &readcmd->sg);
+		if (ret < 0)
+			return ret;
 		command = ContainerRawIo;
 		fibsize = sizeof(struct aac_raw_io) +
 			((le32_to_cpu(readcmd->sg.count)-1) * sizeof(struct sgentryraw));
···
 {
 	u16 fibsize;
 	struct aac_read64 *readcmd;
+	long ret;
+
 	aac_fib_init(fib);
 	readcmd = (struct aac_read64 *) fib_data(fib);
 	readcmd->command = cpu_to_le32(VM_CtHostRead64);
···
 	readcmd->pad   = 0;
 	readcmd->flags = 0;
 
-	aac_build_sg64(cmd, &readcmd->sg);
+	ret = aac_build_sg64(cmd, &readcmd->sg);
+	if (ret < 0)
+		return ret;
 	fibsize = sizeof(struct aac_read64) +
 		((le32_to_cpu(readcmd->sg.count) - 1) *
 		 sizeof (struct sgentry64));
···
 {
 	u16 fibsize;
 	struct aac_read *readcmd;
+	long ret;
+
 	aac_fib_init(fib);
 	readcmd = (struct aac_read *) fib_data(fib);
 	readcmd->command = cpu_to_le32(VM_CtBlockRead);
···
 	readcmd->block = cpu_to_le32((u32)(lba&0xffffffff));
 	readcmd->count = cpu_to_le32(count * 512);
 
-	aac_build_sg(cmd, &readcmd->sg);
+	ret = aac_build_sg(cmd, &readcmd->sg);
+	if (ret < 0)
+		return ret;
 	fibsize = sizeof(struct aac_read) +
 			((le32_to_cpu(readcmd->sg.count) - 1) *
 			 sizeof (struct sgentry));
···
 {
 	struct aac_dev *dev = fib->dev;
 	u16 fibsize, command;
+	long ret;
 
 	aac_fib_init(fib);
 	if (dev->comm_interface == AAC_COMM_MESSAGE_TYPE2 && !dev->sync_mode) {
···
 						   (((aac_cache & 5) != 5) || !fib->dev->cache_protected)) ?
 			cpu_to_le16(RIO2_IO_TYPE_WRITE|RIO2_IO_SUREWRITE) :
 			cpu_to_le16(RIO2_IO_TYPE_WRITE);
-		aac_build_sgraw2(cmd, writecmd2, dev->scsi_host_ptr->sg_tablesize);
+		ret = aac_build_sgraw2(cmd, writecmd2,
+				dev->scsi_host_ptr->sg_tablesize);
+		if (ret < 0)
+			return ret;
 		command = ContainerRawIo2;
 		fibsize = sizeof(struct aac_raw_io2) +
 			((le32_to_cpu(writecmd2->sgeCnt)-1) * sizeof(struct sge_ieee1212));
···
 			cpu_to_le16(RIO_TYPE_WRITE);
 		writecmd->bpTotal = 0;
 		writecmd->bpComplete = 0;
-		aac_build_sgraw(cmd, &writecmd->sg);
+		ret = aac_build_sgraw(cmd, &writecmd->sg);
+		if (ret < 0)
+			return ret;
 		command = ContainerRawIo;
 		fibsize = sizeof(struct aac_raw_io) +
 			((le32_to_cpu(writecmd->sg.count)-1) * sizeof (struct sgentryraw));
···
 {
 	u16 fibsize;
 	struct aac_write64 *writecmd;
+	long ret;
+
 	aac_fib_init(fib);
 	writecmd = (struct aac_write64 *) fib_data(fib);
 	writecmd->command = cpu_to_le32(VM_CtHostWrite64);
···
 	writecmd->pad	= 0;
 	writecmd->flags	= 0;
 
-	aac_build_sg64(cmd, &writecmd->sg);
+	ret = aac_build_sg64(cmd, &writecmd->sg);
+	if (ret < 0)
+		return ret;
 	fibsize = sizeof(struct aac_write64) +
 		((le32_to_cpu(writecmd->sg.count) - 1) *
 		 sizeof (struct sgentry64));
···
 {
 	u16 fibsize;
 	struct aac_write *writecmd;
+	long ret;
+
 	aac_fib_init(fib);
 	writecmd = (struct aac_write *) fib_data(fib);
 	writecmd->command = cpu_to_le32(VM_CtBlockWrite);
···
 	writecmd->sg.count = cpu_to_le32(1);
 	/* ->stable is not used - it did mean which type of write */
 
-	aac_build_sg(cmd, &writecmd->sg);
+	ret = aac_build_sg(cmd, &writecmd->sg);
+	if (ret < 0)
+		return ret;
 	fibsize = sizeof(struct aac_write) +
 		((le32_to_cpu(writecmd->sg.count) - 1) *
 		 sizeof (struct sgentry));
···
 {
 	u16 fibsize;
 	struct aac_srb * srbcmd = aac_scsi_common(fib, cmd);
+	long ret;
 
-	aac_build_sg64(cmd, (struct sgmap64*) &srbcmd->sg);
+	ret = aac_build_sg64(cmd, (struct sgmap64 *) &srbcmd->sg);
+	if (ret < 0)
+		return ret;
 	srbcmd->count = cpu_to_le32(scsi_bufflen(cmd));
 
 	memset(srbcmd->cdb, 0, sizeof(srbcmd->cdb));
···
 {
 	u16 fibsize;
 	struct aac_srb * srbcmd = aac_scsi_common(fib, cmd);
+	long ret;
 
-	aac_build_sg(cmd, (struct sgmap*)&srbcmd->sg);
+	ret = aac_build_sg(cmd, (struct sgmap *)&srbcmd->sg);
+	if (ret < 0)
+		return ret;
 	srbcmd->count = cpu_to_le32(scsi_bufflen(cmd));
 
 	memset(srbcmd->cdb, 0, sizeof(srbcmd->cdb));
···
 	return -1;
 }
 
-static unsigned long aac_build_sg(struct scsi_cmnd* scsicmd, struct sgmap* psg)
+static long aac_build_sg(struct scsi_cmnd *scsicmd, struct sgmap *psg)
 {
 	struct aac_dev *dev;
 	unsigned long byte_count = 0;
···
 	psg->sg[0].count = 0;
 
 	nseg = scsi_dma_map(scsicmd);
-	BUG_ON(nseg < 0);
+	if (nseg < 0)
+		return nseg;
 	if (nseg) {
 		struct scatterlist *sg;
 		int i;
···
 }
 
 
-static unsigned long aac_build_sg64(struct scsi_cmnd* scsicmd, struct sgmap64* psg)
+static long aac_build_sg64(struct scsi_cmnd *scsicmd, struct sgmap64 *psg)
 {
 	struct aac_dev *dev;
 	unsigned long byte_count = 0;
···
 	psg->sg[0].count = 0;
 
 	nseg = scsi_dma_map(scsicmd);
-	BUG_ON(nseg < 0);
+	if (nseg < 0)
+		return nseg;
 	if (nseg) {
 		struct scatterlist *sg;
 		int i;
···
 	return byte_count;
 }
 
-static unsigned long aac_build_sgraw(struct scsi_cmnd* scsicmd, struct sgmapraw* psg)
+static long aac_build_sgraw(struct scsi_cmnd *scsicmd, struct sgmapraw *psg)
 {
 	unsigned long byte_count = 0;
 	int nseg;
···
 	psg->sg[0].flags = 0;
 
 	nseg = scsi_dma_map(scsicmd);
-	BUG_ON(nseg < 0);
+	if (nseg < 0)
+		return nseg;
 	if (nseg) {
 		struct scatterlist *sg;
 		int i;
···
 	return byte_count;
 }
 
-static unsigned long aac_build_sgraw2(struct scsi_cmnd *scsicmd, struct aac_raw_io2 *rio2, int sg_max)
+static long aac_build_sgraw2(struct scsi_cmnd *scsicmd,
+				struct aac_raw_io2 *rio2, int sg_max)
 {
 	unsigned long byte_count = 0;
 	int nseg;
 
 	nseg = scsi_dma_map(scsicmd);
-	BUG_ON(nseg < 0);
+	if (nseg < 0)
+		return nseg;
 	if (nseg) {
 		struct scatterlist *sg;
 		int i, conformable = 0;

drivers/scsi/aacraid/aacraid.h

···
  *----------------------------------------------------------------------------*/
 
 #ifndef AAC_DRIVER_BUILD
-# define AAC_DRIVER_BUILD 29800
+# define AAC_DRIVER_BUILD 29801
 # define AAC_DRIVER_BRANCH "-ms"
 #endif
 #define MAXIMUM_NUM_CONTAINERS	32