2 * SCSI library functions depending on DMA
5 #include <linux/blkdev.h>
6 #include <linux/device.h>
7 #include <linux/kernel.h>
10 #include <scsi/scsi_cmnd.h>
11 #include <scsi/scsi_device.h>
12 #include <scsi/scsi_host.h>
15 * scsi_dma_map - perform DMA mapping against command's sg lists
18 * Returns the number of sg lists actually used, zero if the sg lists
19 * is NULL, or -ENOMEM if the mapping failed.
21 int scsi_dma_map(struct scsi_cmnd *cmd)
25 if (scsi_sg_count(cmd)) {
26 struct device *dev = cmd->device->host->shost_gendev.parent;
28 nseg = dma_map_sg(dev, scsi_sglist(cmd), scsi_sg_count(cmd),
29 cmd->sc_data_direction);
35 EXPORT_SYMBOL(scsi_dma_map);
38 * scsi_dma_unmap - unmap command's sg lists mapped by scsi_dma_map
41 void scsi_dma_unmap(struct scsi_cmnd *cmd)
43 if (scsi_sg_count(cmd)) {
44 struct device *dev = cmd->device->host->shost_gendev.parent;
46 dma_unmap_sg(dev, scsi_sglist(cmd), scsi_sg_count(cmd),
47 cmd->sc_data_direction);
50 EXPORT_SYMBOL(scsi_dma_unmap);