summaryrefslogtreecommitdiffstats
path: root/drivers/scsi/scsi_lib_dma.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/scsi/scsi_lib_dma.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/scsi/scsi_lib_dma.c')
-rw-r--r--drivers/scsi/scsi_lib_dma.c52
1 files changed, 52 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_lib_dma.c b/drivers/scsi/scsi_lib_dma.c
new file mode 100644
index 000000000..572391527
--- /dev/null
+++ b/drivers/scsi/scsi_lib_dma.c
@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SCSI library functions depending on DMA
+ */
+
+#include <linux/blkdev.h>
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_host.h>
+
+/**
+ * scsi_dma_map - perform DMA mapping against command's sg lists
+ * @cmd: scsi command
+ *
+ * Returns the number of sg lists actually used, zero if the sg lists
+ * is NULL, or -ENOMEM if the mapping failed.
+ */
+int scsi_dma_map(struct scsi_cmnd *cmd)
+{
+ int nseg = 0;
+
+ if (scsi_sg_count(cmd)) {
+ struct device *dev = cmd->device->host->dma_dev;
+
+ nseg = dma_map_sg(dev, scsi_sglist(cmd), scsi_sg_count(cmd),
+ cmd->sc_data_direction);
+ if (unlikely(!nseg))
+ return -ENOMEM;
+ }
+ return nseg;
+}
+EXPORT_SYMBOL(scsi_dma_map);
+
+/**
+ * scsi_dma_unmap - unmap command's sg lists mapped by scsi_dma_map
+ * @cmd: scsi command
+ */
+void scsi_dma_unmap(struct scsi_cmnd *cmd)
+{
+ if (scsi_sg_count(cmd)) {
+ struct device *dev = cmd->device->host->dma_dev;
+
+ dma_unmap_sg(dev, scsi_sglist(cmd), scsi_sg_count(cmd),
+ cmd->sc_data_direction);
+ }
+}
+EXPORT_SYMBOL(scsi_dma_unmap);