diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c
index 664d634c98..b0b39f1e92 100644
--- a/hw/scsi/scsi-disk.c
+++ b/hw/scsi/scsi-disk.c
@@ -2578,8 +2578,6 @@ static int get_device_type(SCSIDiskState *s)
 {
     uint8_t cmd[16];
     uint8_t buf[36];
-    uint8_t sensebuf[8];
-    sg_io_hdr_t io_header;
     int ret;
 
     memset(cmd, 0, sizeof(cmd));
@@ -2587,19 +2585,9 @@ static int get_device_type(SCSIDiskState *s)
     cmd[0] = INQUIRY;
     cmd[4] = sizeof(buf);
 
-    memset(&io_header, 0, sizeof(io_header));
-    io_header.interface_id = 'S';
-    io_header.dxfer_direction = SG_DXFER_FROM_DEV;
-    io_header.dxfer_len = sizeof(buf);
-    io_header.dxferp = buf;
-    io_header.cmdp = cmd;
-    io_header.cmd_len = sizeof(cmd);
-    io_header.mx_sb_len = sizeof(sensebuf);
-    io_header.sbp = sensebuf;
-    io_header.timeout = 6000; /* XXX */
-
-    ret = blk_ioctl(s->qdev.conf.blk, SG_IO, &io_header);
-    if (ret < 0 || io_header.driver_status || io_header.host_status) {
+    ret = scsi_SG_IO_FROM_DEV(s->qdev.conf.blk, cmd, sizeof(cmd),
+                              buf, sizeof(buf));
+    if (ret < 0) {
         return -1;
     }
     s->qdev.type = buf[0];
diff --git a/hw/scsi/scsi-generic.c b/hw/scsi/scsi-generic.c
index a04a704bbf..61abc2763a 100644
--- a/hw/scsi/scsi-generic.c
+++ b/hw/scsi/scsi-generic.c
@@ -409,12 +409,35 @@ static int read_naa_id(const uint8_t *p, uint64_t *p_wwn)
     return -EINVAL;
 }
 
+int scsi_SG_IO_FROM_DEV(BlockBackend *blk, uint8_t *cmd, uint8_t cmd_size,
+                        uint8_t *buf, uint8_t buf_size)
+{
+    sg_io_hdr_t io_header;
+    uint8_t sensebuf[8];
+    int ret;
+
+    memset(&io_header, 0, sizeof(io_header));
+    io_header.interface_id = 'S';
+    io_header.dxfer_direction = SG_DXFER_FROM_DEV;
+    io_header.dxfer_len = buf_size;
+    io_header.dxferp = buf;
+    io_header.cmdp = cmd;
+    io_header.cmd_len = cmd_size;
+    io_header.mx_sb_len = sizeof(sensebuf);
+    io_header.sbp = sensebuf;
+    io_header.timeout = 6000; /* XXX */
+
+    ret = blk_ioctl(blk, SG_IO, &io_header);
+    if (ret < 0 || io_header.driver_status || io_header.host_status) {
+        return -1;
+    }
+    return 0;
+}
+
 void scsi_generic_read_device_identification(SCSIDevice *s)
 {
     uint8_t cmd[6];
     uint8_t buf[250];
-    uint8_t sensebuf[8];
-    sg_io_hdr_t io_header;
     int ret;
     int i, len;
 
@@ -425,19 +448,9 @@ void scsi_generic_read_device_identification(SCSIDevice *s)
     cmd[2] = 0x83;
     cmd[4] = sizeof(buf);
 
-    memset(&io_header, 0, sizeof(io_header));
-    io_header.interface_id = 'S';
-    io_header.dxfer_direction = SG_DXFER_FROM_DEV;
-    io_header.dxfer_len = sizeof(buf);
-    io_header.dxferp = buf;
-    io_header.cmdp = cmd;
-    io_header.cmd_len = sizeof(cmd);
-    io_header.mx_sb_len = sizeof(sensebuf);
-    io_header.sbp = sensebuf;
-    io_header.timeout = 6000; /* XXX */
-
-    ret = blk_ioctl(s->conf.blk, SG_IO, &io_header);
-    if (ret < 0 || io_header.driver_status || io_header.host_status) {
+    ret = scsi_SG_IO_FROM_DEV(s->conf.blk, cmd, sizeof(cmd),
+                              buf, sizeof(buf));
+    if (ret < 0) {
         return;
     }
 
@@ -470,8 +483,6 @@ static int get_stream_blocksize(BlockBackend *blk)
 {
     uint8_t cmd[6];
     uint8_t buf[12];
-    uint8_t sensebuf[8];
-    sg_io_hdr_t io_header;
     int ret;
 
     memset(cmd, 0, sizeof(cmd));
@@ -479,21 +490,11 @@ static int get_stream_blocksize(BlockBackend *blk)
     cmd[0] = MODE_SENSE;
     cmd[4] = sizeof(buf);
 
-    memset(&io_header, 0, sizeof(io_header));
-    io_header.interface_id = 'S';
-    io_header.dxfer_direction = SG_DXFER_FROM_DEV;
-    io_header.dxfer_len = sizeof(buf);
-    io_header.dxferp = buf;
-    io_header.cmdp = cmd;
-    io_header.cmd_len = sizeof(cmd);
-    io_header.mx_sb_len = sizeof(sensebuf);
-    io_header.sbp = sensebuf;
-    io_header.timeout = 6000; /* XXX */
-
-    ret = blk_ioctl(blk, SG_IO, &io_header);
-    if (ret < 0 || io_header.driver_status || io_header.host_status) {
+    ret = scsi_SG_IO_FROM_DEV(blk, cmd, sizeof(cmd), buf, sizeof(buf));
+    if (ret < 0) {
         return -1;
     }
+
     return (buf[9] << 16) | (buf[10] << 8) | buf[11];
 }
 
diff --git a/include/hw/scsi/scsi.h b/include/hw/scsi/scsi.h
index 138eb79a5f..75eced34d3 100644
--- a/include/hw/scsi/scsi.h
+++ b/include/hw/scsi/scsi.h
@@ -187,6 +187,8 @@ void scsi_device_unit_attention_reported(SCSIDevice *dev);
 void scsi_generic_read_device_identification(SCSIDevice *dev);
 int scsi_device_get_sense(SCSIDevice *dev, uint8_t *buf, int len, bool fixed);
 int scsi_disk_emulate_vpd_page(SCSIRequest *req, uint8_t *outbuf);
+int scsi_SG_IO_FROM_DEV(BlockBackend *blk, uint8_t *cmd, uint8_t cmd_size,
+                        uint8_t *buf, uint8_t buf_size);
 SCSIDevice *scsi_device_find(SCSIBus *bus, int channel, int target, int lun);
 
 /* scsi-generic.c. */