scsi: add bsg support

The Linux kernel supports two different versions of the SG_IO API,
namely v3 and v4. This patch adds support for version 4 of this API.
At least the sg3_utils package supports version 4 of this API.  Version
4 of this API is used if /dev/bsg/H:C:I:L is used as device name.

This patch has been tested by inspecting the output of the following
commands:

modprobe scsi_debug dev_size_mb=16 delay=0
dev=$(lsscsi | sed -n '/ scsi_debug /s,^[^/]*,,p')
./strace -eioctl -s256 sg_inq $dev
echo 'Test XDWRITEREAD(10)'
bsg=/dev/bsg/$(lsscsi | sed -n '/ scsi_debug /s,^\[\([^]]\+\)\].*,\1,p')
dd if=/dev/zero bs=512 count=1 |
  ./strace -eioctl -s256 sg_raw -s 512 -r 1024 $bsg 53 00 00 00 00 01 00 00 01 00

* configure.ac (AC_CHECK_HEADERS): Add linux/bsg.h.
* xlat/bsg_protocol.in: New file.
* xlat/bsg_subprotocol.in: Likewise.
* scsi.c: Include them and <linux/bsg.h>.
(print_sg_io_v3_req, print_sg_io_v3_res, print_sg_io_v4_req,
print_sg_io_v4_res): New functions.
(print_sg_io_req, print_sg_io_res): Use them.
(scsi_ioctl): Update callers.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>

configure.ac

@@ -222,6 +222,7 @@ AC_CHECK_HEADERS(m4_normalize([
 	elf.h
 	inttypes.h
 	ioctls.h
+	linux/bsg.h
 	linux/falloc.h
 	linux/filter.h
 	linux/hiddev.h

scsi.c

@@ -33,7 +33,14 @@
 # include <sys/ioctl.h>
 # include <scsi/sg.h>
 
-#include "xlat/sg_io_dxfer_direction.h"
+# include "xlat/sg_io_dxfer_direction.h"
+
+# ifdef HAVE_LINUX_BSG_H
+#  include <linux/bsg.h>
+#  include <sys/uio.h>
+#  include "xlat/bsg_protocol.h"
+#  include "xlat/bsg_subprotocol.h"
+# endif
 
 static void
 print_sg_io_buffer(struct tcb *tcp, unsigned long addr, const unsigned int len)
@@ -61,83 +68,216 @@ out:
 }
 
 static void
-print_sg_io_req(struct tcb *tcp, struct sg_io_hdr *sg_io)
+print_sg_io_v3_req(struct tcb *tcp, long arg)
 {
-	tprintf("{'%c', ", sg_io->interface_id);
+	struct sg_io_hdr sg_io;
-	printxval(sg_io_dxfer_direction, sg_io->dxfer_direction,
-		  "SG_DXFER_???");
-	tprintf(", cmd[%u]=", sg_io->cmd_len);
-	print_sg_io_buffer(tcp, (unsigned long) sg_io->cmdp, sg_io->cmd_len);
-	tprintf(", mx_sb_len=%d, ", sg_io->mx_sb_len);
-	tprintf("iovec_count=%d, ", sg_io->iovec_count);
-	tprintf("dxfer_len=%u, ", sg_io->dxfer_len);
-	tprintf("timeout=%u, ", sg_io->timeout);
-	tprintf("flags=%#x", sg_io->flags);
 
-	if (sg_io->dxfer_direction == SG_DXFER_TO_DEV ||
+	if (umove(tcp, arg, &sg_io) < 0) {
-	    sg_io->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
+		tprintf(", %#lx", arg);
-		tprintf(", data[%u]=", sg_io->dxfer_len);
+		return;
-		if (sg_io->iovec_count)
+	}
-			tprint_iov_upto(tcp, sg_io->iovec_count,
+
-					(unsigned long) sg_io->dxferp, 1,
+	tprints(", ");
-					sg_io->dxfer_len);
+	printxval(sg_io_dxfer_direction, sg_io.dxfer_direction,
+		  "SG_DXFER_???");
+	tprintf(", cmd[%u]=", sg_io.cmd_len);
+	print_sg_io_buffer(tcp, (unsigned long) sg_io.cmdp, sg_io.cmd_len);
+	tprintf(", mx_sb_len=%d", sg_io.mx_sb_len);
+	tprintf(", iovec_count=%d", sg_io.iovec_count);
+	tprintf(", dxfer_len=%u", sg_io.dxfer_len);
+	tprintf(", timeout=%u", sg_io.timeout);
+	tprintf(", flags=%#x", sg_io.flags);
+
+	if (sg_io.dxfer_direction == SG_DXFER_TO_DEV ||
+	    sg_io.dxfer_direction == SG_DXFER_TO_FROM_DEV) {
+		tprintf(", data[%u]=", sg_io.dxfer_len);
+		if (sg_io.iovec_count)
+			tprint_iov_upto(tcp, sg_io.iovec_count,
+					(unsigned long) sg_io.dxferp, 1,
+					sg_io.dxfer_len);
 		else
-			print_sg_io_buffer(tcp, (unsigned long) sg_io->dxferp,
+			print_sg_io_buffer(tcp, (unsigned long) sg_io.dxferp,
-					   sg_io->dxfer_len);
+					   sg_io.dxfer_len);
 	}
 }
 
 static void
-print_sg_io_res(struct tcb *tcp, struct sg_io_hdr *sg_io)
+print_sg_io_v3_res(struct tcb *tcp, long arg)
 {
-	if (sg_io->dxfer_direction == SG_DXFER_FROM_DEV ||
+	struct sg_io_hdr sg_io;
-	    sg_io->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
-		uint32_t din_len = sg_io->dxfer_len;
 
-		if (sg_io->resid > 0)
+	if (umove(tcp, arg, &sg_io) < 0) {
-			din_len -= sg_io->resid;
+		tprintf(", %#lx", arg);
+		return;
+	}
+
+	if (sg_io.dxfer_direction == SG_DXFER_FROM_DEV ||
+	    sg_io.dxfer_direction == SG_DXFER_TO_FROM_DEV) {
+		uint32_t din_len = sg_io.dxfer_len;
+
+		if (sg_io.resid > 0)
+			din_len -= sg_io.resid;
 		tprintf(", data[%u]=", din_len);
-		if (sg_io->iovec_count)
+		if (sg_io.iovec_count)
-			tprint_iov_upto(tcp, sg_io->iovec_count,
+			tprint_iov_upto(tcp, sg_io.iovec_count,
-					(unsigned long) sg_io->dxferp, 1,
+					(unsigned long) sg_io.dxferp, 1,
 					din_len);
 		else
-			print_sg_io_buffer(tcp, (unsigned long) sg_io->dxferp,
+			print_sg_io_buffer(tcp, (unsigned long) sg_io.dxferp,
 					   din_len);
 	}
-	tprintf(", status=%02x, ", sg_io->status);
+	tprintf(", status=%02x", sg_io.status);
-	tprintf("masked_status=%02x, ", sg_io->masked_status);
+	tprintf(", masked_status=%02x", sg_io.masked_status);
-	tprintf("sb[%u]=", sg_io->sb_len_wr);
+	tprintf(", sb[%u]=", sg_io.sb_len_wr);
-	print_sg_io_buffer(tcp, (unsigned long) sg_io->sbp, sg_io->sb_len_wr);
+	print_sg_io_buffer(tcp, (unsigned long) sg_io.sbp, sg_io.sb_len_wr);
-	tprintf(", host_status=%#x, ", sg_io->host_status);
+	tprintf(", host_status=%#x", sg_io.host_status);
-	tprintf("driver_status=%#x, ", sg_io->driver_status);
+	tprintf(", driver_status=%#x", sg_io.driver_status);
-	tprintf("resid=%d, ", sg_io->resid);
+	tprintf(", resid=%d", sg_io.resid);
-	tprintf("duration=%d, ", sg_io->duration);
+	tprintf(", duration=%d", sg_io.duration);
-	tprintf("info=%#x}", sg_io->info);
+	tprintf(", info=%#x", sg_io.info);
+}
+
+#ifdef HAVE_LINUX_BSG_H
+
+static void
+print_sg_io_v4_req(struct tcb *tcp, long arg)
+{
+	struct sg_io_v4 sg_io;
+
+	if (umove(tcp, arg, &sg_io) < 0) {
+		tprintf(", %#lx", arg);
+		return;
+	}
+
+	tprints(", ");
+	printxval(bsg_protocol, sg_io.protocol, "BSG_PROTOCOL_???");
+	tprints(", ");
+	printxval(bsg_subprotocol, sg_io.subprotocol, "BSG_SUB_PROTOCOL_???");
+	tprintf(", request[%u]=", sg_io.request_len);
+	print_sg_io_buffer(tcp, sg_io.request, sg_io.request_len);
+	tprintf(", request_tag=%llu", sg_io.request_tag);
+	tprintf(", request_attr=%u", sg_io.request_attr);
+	tprintf(", request_priority=%u", sg_io.request_priority);
+	tprintf(", request_extra=%u", sg_io.request_extra);
+	tprintf(", max_response_len=%u", sg_io.max_response_len);
+
+	tprintf(", dout_iovec_count=%u", sg_io.dout_iovec_count);
+	tprintf(", dout_xfer_len=%u", sg_io.dout_xfer_len);
+	tprintf(", din_iovec_count=%u", sg_io.din_iovec_count);
+	tprintf(", din_xfer_len=%u", sg_io.din_xfer_len);
+	tprintf(", timeout=%u", sg_io.timeout);
+	tprintf(", flags=%u", sg_io.flags);
+	tprintf(", usr_ptr=%llu", sg_io.usr_ptr);
+	tprintf(", spare_in=%u", sg_io.spare_in);
+	tprintf(", dout[%u]=", sg_io.dout_xfer_len);
+	if (sg_io.dout_iovec_count)
+		tprint_iov_upto(tcp, sg_io.dout_iovec_count, sg_io.dout_xferp,
+				1, sg_io.dout_xfer_len);
+	else
+		print_sg_io_buffer(tcp, sg_io.dout_xferp, sg_io.dout_xfer_len);
+}
+
+static void
+print_sg_io_v4_res(struct tcb *tcp, long arg)
+{
+	struct sg_io_v4 sg_io;
+	uint32_t din_len;
+
+	if (umove(tcp, arg, &sg_io) < 0) {
+		tprintf(", %#lx", arg);
+		return;
+	}
+
+	tprintf(", response[%u]=", sg_io.response_len);
+	print_sg_io_buffer(tcp, sg_io.response, sg_io.response_len);
+	din_len = sg_io.din_xfer_len;
+	if (sg_io.din_resid > 0)
+		din_len -= sg_io.din_resid;
+	tprintf(", din[%u]=", din_len);
+	if (sg_io.din_iovec_count)
+		tprint_iov_upto(tcp, sg_io.din_iovec_count, sg_io.din_xferp,
+				1, din_len);
+	else
+		print_sg_io_buffer(tcp, sg_io.din_xferp, din_len);
+	tprintf(", driver_status=%u", sg_io.driver_status);
+	tprintf(", transport_status=%u", sg_io.transport_status);
+	tprintf(", device_status=%u", sg_io.device_status);
+	tprintf(", retry_delay=%u", sg_io.retry_delay);
+	tprintf(", info=%u", sg_io.info);
+	tprintf(", duration=%u", sg_io.duration);
+	tprintf(", response_len=%u", sg_io.response_len);
+	tprintf(", din_resid=%u", sg_io.din_resid);
+	tprintf(", dout_resid=%u", sg_io.dout_resid);
+	tprintf(", generated_tag=%llu", sg_io.generated_tag);
+	tprintf(", spare_out=%u", sg_io.spare_out);
+}
+
+#else /* !HAVE_LINUX_BSG_H */
+
+static void
+print_sg_io_v4_req(struct tcb *tcp, long arg)
+{
+	tprintf(", %#lx", arg);
+}
+
+static void
+print_sg_io_v4_res(struct tcb *tcp, long arg)
+{
+}
+
+#endif
+
+static void
+print_sg_io_req(struct tcb *tcp, uint32_t iid, long arg)
+{
+	tprintf("{'%c'", iid);
+
+	switch (iid) {
+	case 'S':
+		print_sg_io_v3_req(tcp, arg);
+		break;
+	case 'Q':
+		print_sg_io_v4_req(tcp, arg);
+		break;
+	default:
+		tprints(", ...");
+	}
+
+}
+
+static void
+print_sg_io_res(struct tcb *tcp, uint32_t iid, long arg)
+{
+	if (!syserror(tcp)) {
+		switch (iid) {
+		case 'S':
+			print_sg_io_v3_res(tcp, arg);
+			break;
+		case 'Q':
+			print_sg_io_v4_res(tcp, arg);
+			break;
+		}
+	}
+
+	tprintf("}");
 }
 
 int
 scsi_ioctl(struct tcb *tcp, const unsigned int code, long arg)
 {
+	uint32_t iid;
+
 	switch (code) {
 	case SG_IO:
 		if (entering(tcp)) {
-			struct sg_io_hdr sg_io;
+			tprints(", ");
-
+			if (umove(tcp, arg, &iid) < 0)
-			if (umove(tcp, arg, &sg_io) < 0)
+				tprintf("%#lx", arg);
-				tprintf(", %#lx", arg);
-			else {
-				tprints(", ");
-				print_sg_io_req(tcp, &sg_io);
-			}
-		}
-		if (exiting(tcp)) {
-			struct sg_io_hdr sg_io;
-
-			if (!syserror(tcp) && umove(tcp, arg, &sg_io) >= 0)
-				print_sg_io_res(tcp, &sg_io);
 			else
-				tprints("}");
+				print_sg_io_req(tcp, iid, arg);
+		} else {
+			if (umove(tcp, arg, &iid) >= 0)
+				print_sg_io_res(tcp, iid, arg);
 		}
 		break;
 	default:

xlat/bsg_protocol.in

@@ -0,0 +1 @@
+BSG_PROTOCOL_SCSI

xlat/bsg_subprotocol.in

@@ -0,0 +1,3 @@
+BSG_SUB_PROTOCOL_SCSI_CMD
+BSG_SUB_PROTOCOL_SCSI_TMF
+BSG_SUB_PROTOCOL_SCSI_TRANSPORT