scsi: core: Clean up allocation and freeing of sgtables

Rename scsi_init_io() to scsi_alloc_sgtables(), and ensure callers call
scsi_free_sgtables() to cleanup failures close to scsi_init_io() instead of
leaking it down the generic I/O submission path.

Link: https://lore.kernel.org/r/20201005084130.143273-9-hch@lst.de
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 15 insertions, 12 deletions

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 7aa69888d0625..cfe59edaf8384 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -902,7 +902,7 @@ static blk_status_t sd_setup_unmap_cmnd(struct scsi_cmnd *cmd)
 	cmd->transfersize = data_len;
 	rq->timeout = SD_TIMEOUT;
 
-	return scsi_init_io(cmd);
+	return scsi_alloc_sgtables(cmd);
 }
 
 static blk_status_t sd_setup_write_same16_cmnd(struct scsi_cmnd *cmd,
@@ -934,7 +934,7 @@ static blk_status_t sd_setup_write_same16_cmnd(struct scsi_cmnd *cmd,
 	cmd->transfersize = data_len;
 	rq->timeout = unmap ? SD_TIMEOUT : SD_WRITE_SAME_TIMEOUT;
 
-	return scsi_init_io(cmd);
+	return scsi_alloc_sgtables(cmd);
 }
 
 static blk_status_t sd_setup_write_same10_cmnd(struct scsi_cmnd *cmd,
@@ -966,7 +966,7 @@ static blk_status_t sd_setup_write_same10_cmnd(struct scsi_cmnd *cmd,
 	cmd->transfersize = data_len;
 	rq->timeout = unmap ? SD_TIMEOUT : SD_WRITE_SAME_TIMEOUT;
 
-	return scsi_init_io(cmd);
+	return scsi_alloc_sgtables(cmd);
 }
 
 static blk_status_t sd_setup_write_zeroes_cmnd(struct scsi_cmnd *cmd)
@@ -1107,7 +1107,7 @@ static blk_status_t sd_setup_write_same_cmnd(struct scsi_cmnd *cmd)
 	 * knows how much to actually write.
 	 */
 	rq->__data_len = sdp->sector_size;
-	ret = scsi_init_io(cmd);
+	ret = scsi_alloc_sgtables(cmd);
 	rq->__data_len = blk_rq_bytes(rq);
 
 	return ret;
@@ -1226,23 +1226,24 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd)
 	unsigned int dif;
 	bool dix;
 
-	ret = scsi_init_io(cmd);
+	ret = scsi_alloc_sgtables(cmd);
 	if (ret != BLK_STS_OK)
 		return ret;
 
+	ret = BLK_STS_IOERR;
 	if (!scsi_device_online(sdp) || sdp->changed) {
 		scmd_printk(KERN_ERR, cmd, "device offline or changed\n");
-		return BLK_STS_IOERR;
+		goto fail;
 	}
 
 	if (blk_rq_pos(rq) + blk_rq_sectors(rq) > get_capacity(rq->rq_disk)) {
 		scmd_printk(KERN_ERR, cmd, "access beyond end of device\n");
-		return BLK_STS_IOERR;
+		goto fail;
 	}
 
 	if ((blk_rq_pos(rq) & mask) || (blk_rq_sectors(rq) & mask)) {
 		scmd_printk(KERN_ERR, cmd, "request not aligned to the logical block size\n");
-		return BLK_STS_IOERR;
+		goto fail;
 	}
 
 	/*
@@ -1264,7 +1265,7 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd)
 	if (req_op(rq) == REQ_OP_ZONE_APPEND) {
 		ret = sd_zbc_prepare_zone_append(cmd, &lba, nr_blocks);
 		if (ret)
-			return ret;
+			goto fail;
 	}
 
 	fua = rq->cmd_flags & REQ_FUA ? 0x8 : 0;
@@ -1292,7 +1293,7 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd)
 	}
 
 	if (unlikely(ret != BLK_STS_OK))
-		return ret;
+		goto fail;
 
 	/*
 	 * We shouldn't disconnect in the middle of a sector, so with a dumb
@@ -1316,10 +1317,12 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd)
 				     blk_rq_sectors(rq)));
 
 	/*
-	 * This indicates that the command is ready from our end to be
-	 * queued.
+	 * This indicates that the command is ready from our end to be queued.
 	 */
 	return BLK_STS_OK;
+fail:
+	scsi_free_sgtables(cmd);
+	return ret;
 }
 
 static blk_status_t sd_init_command(struct scsi_cmnd *cmd)