diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 67b50baa943c..83284a8fa2cd 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1025,7 +1025,6 @@ static int sd_setup_read_write_cmnd(struct scsi_cmnd *SCpnt)
 	struct gendisk *disk = rq->rq_disk;
 	struct scsi_disk *sdkp = scsi_disk(disk);
 	sector_t block = blk_rq_pos(rq);
-	sector_t threshold;
 	unsigned int this_count = blk_rq_sectors(rq);
 	unsigned int dif, dix;
 	bool zoned_write = sd_is_zoned(sdkp) && rq_data_dir(rq) == WRITE;
@@ -1071,20 +1070,22 @@ static int sd_setup_read_write_cmnd(struct scsi_cmnd *SCpnt)
 		goto out;
 	}
 
-	/*
-	 * Some SD card readers can't handle multi-sector accesses which touch
-	 * the last one or two hardware sectors.  Split accesses as needed.
-	 */
-	threshold = get_capacity(disk) - SD_LAST_BUGGY_SECTORS *
-		(sdp->sector_size / 512);
+	if (unlikely(sdp->last_sector_bug)) {
+		sector_t threshold;
 
-	if (unlikely(sdp->last_sector_bug && block + this_count > threshold)) {
-		if (block < threshold) {
-			/* Access up to the threshold but not beyond */
-			this_count = threshold - block;
-		} else {
+		/*
+		 * Some SD card readers can't handle multi-sector accesses
+		 * which touch the last one or two hardware sectors.  Split
+		 * accesses as needed.
+		 */
+		threshold = get_capacity(disk) - SD_LAST_BUGGY_SECTORS *
+			(sdp->sector_size / 512);
+		if (block >= threshold) {
 			/* Access only a single hardware sector */
 			this_count = sdp->sector_size / 512;
+		} else if (block + this_count > threshold) {
+			/* Access up to the threshold but not beyond */
+			this_count = threshold - block;
 		}
 	}
 
@@ -1102,34 +1103,17 @@ static int sd_setup_read_write_cmnd(struct scsi_cmnd *SCpnt)
 	 * and not force the scsi disk driver to use bounce buffers
 	 * for this.
 	 */
-	if (sdp->sector_size == 1024) {
-		if ((block & 1) || (blk_rq_sectors(rq) & 1)) {
+	if (sdp->sector_size != 512) {
+		if ((block | this_count) & (sdp->sector_size / 512 - 1)) {
 			scmd_printk(KERN_ERR, SCpnt,
-				    "Bad block number requested\n");
+				    "Bad block number requested: block number = %llu, sector count = %u, sector size = %u bytes\n",
+				    block + 0ULL, this_count, sdp->sector_size);
 			goto out;
 		} else {
-			block = block >> 1;
-			this_count = this_count >> 1;
-		}
-	}
-	if (sdp->sector_size == 2048) {
-		if ((block & 3) || (blk_rq_sectors(rq) & 3)) {
-			scmd_printk(KERN_ERR, SCpnt,
-				    "Bad block number requested\n");
-			goto out;
-		} else {
-			block = block >> 2;
-			this_count = this_count >> 2;
-		}
-	}
-	if (sdp->sector_size == 4096) {
-		if ((block & 7) || (blk_rq_sectors(rq) & 7)) {
-			scmd_printk(KERN_ERR, SCpnt,
-				    "Bad block number requested\n");
-			goto out;
-		} else {
-			block = block >> 3;
-			this_count = this_count >> 3;
+			int shift = ilog2(sdp->sector_size / 512);
+
+			block = block >> shift;
+			this_count = this_count >> shift;
 		}
 	}
 	if (rq_data_dir(rq) == WRITE) {
@@ -1173,56 +1157,26 @@ static int sd_setup_read_write_cmnd(struct scsi_cmnd *SCpnt)
 		SCpnt->cmnd[7] = 0x18;
 		SCpnt->cmnd[9] = (rq_data_dir(rq) == READ) ? READ_32 : WRITE_32;
 		SCpnt->cmnd[10] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
-
 		/* LBA */
-		SCpnt->cmnd[12] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
-		SCpnt->cmnd[13] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
-		SCpnt->cmnd[14] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
-		SCpnt->cmnd[15] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
-		SCpnt->cmnd[16] = (unsigned char) (block >> 24) & 0xff;
-		SCpnt->cmnd[17] = (unsigned char) (block >> 16) & 0xff;
-		SCpnt->cmnd[18] = (unsigned char) (block >> 8) & 0xff;
-		SCpnt->cmnd[19] = (unsigned char) block & 0xff;
-
+		put_unaligned_be64(block, &SCpnt->cmnd[12]);
 		/* Expected Indirect LBA */
-		SCpnt->cmnd[20] = (unsigned char) (block >> 24) & 0xff;
-		SCpnt->cmnd[21] = (unsigned char) (block >> 16) & 0xff;
-		SCpnt->cmnd[22] = (unsigned char) (block >> 8) & 0xff;
-		SCpnt->cmnd[23] = (unsigned char) block & 0xff;
-
+		put_unaligned_be32(block, &SCpnt->cmnd[20]);
 		/* Transfer length */
-		SCpnt->cmnd[28] = (unsigned char) (this_count >> 24) & 0xff;
-		SCpnt->cmnd[29] = (unsigned char) (this_count >> 16) & 0xff;
-		SCpnt->cmnd[30] = (unsigned char) (this_count >> 8) & 0xff;
-		SCpnt->cmnd[31] = (unsigned char) this_count & 0xff;
+		put_unaligned_be32(this_count, &SCpnt->cmnd[28]);
 	} else if (sdp->use_16_for_rw || (this_count > 0xffff)) {
 		SCpnt->cmnd[0] += READ_16 - READ_6;
 		SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
-		SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
-		SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
-		SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
-		SCpnt->cmnd[5] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
-		SCpnt->cmnd[6] = (unsigned char) (block >> 24) & 0xff;
-		SCpnt->cmnd[7] = (unsigned char) (block >> 16) & 0xff;
-		SCpnt->cmnd[8] = (unsigned char) (block >> 8) & 0xff;
-		SCpnt->cmnd[9] = (unsigned char) block & 0xff;
-		SCpnt->cmnd[10] = (unsigned char) (this_count >> 24) & 0xff;
-		SCpnt->cmnd[11] = (unsigned char) (this_count >> 16) & 0xff;
-		SCpnt->cmnd[12] = (unsigned char) (this_count >> 8) & 0xff;
-		SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
+		put_unaligned_be64(block, &SCpnt->cmnd[2]);
+		put_unaligned_be32(this_count, &SCpnt->cmnd[10]);
 		SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
 	} else if ((this_count > 0xff) || (block > 0x1fffff) ||
 		   scsi_device_protection(SCpnt->device) ||
 		   SCpnt->device->use_10_for_rw) {
 		SCpnt->cmnd[0] += READ_10 - READ_6;
 		SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
-		SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
-		SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
-		SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
-		SCpnt->cmnd[5] = (unsigned char) block & 0xff;
+		put_unaligned_be32(block, &SCpnt->cmnd[2]);
 		SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
-		SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
-		SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
+		put_unaligned_be16(this_count, &SCpnt->cmnd[7]);
 	} else {
 		if (unlikely(rq->cmd_flags & REQ_FUA)) {
 			/*
