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authorCornelia Huck <cornelia.huck@de.ibm.com>2007-07-09 11:59:59 -0700
committerJames Bottomley <jejb@mulgrave.localdomain>2007-07-14 19:28:10 -0500
commit7689e82efdb636e8a076a1293b977bce313110c5 (patch)
tree3d8702ff24a205db7670ad5425e3a35fe45b0f00 /drivers/scsi/scsi_lib_dma.c
parent6d877688ef411313c94aa3c83c7473fbec6db32c (diff)
[SCSI] don't build scsi_dma_{map,unmap} for !HAS_DMA
With dma-mapping-prevent-dma-dependent-code-from-linking-on.patch scsi fails to build on !HAS_DMA architectures: drivers/built-in.o(.text+0x20af6): In function `scsi_dma_map': : undefined reference to `dma_map_sg' drivers/built-in.o(.text+0x20b5c): In function `scsi_dma_unmap': : undefined reference to `dma_unmap_sg' I split those functions out into a new file. Builds on s390 and i386. Move scsi_dma_{map,unmap} into scsi_lib_dma.c which is only build if HAS_DMA is set. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: James Bottomley <James.Bottomley@SteelEye.com> Cc: Jeff Garzik <jeff@garzik.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Diffstat (limited to 'drivers/scsi/scsi_lib_dma.c')
-rw-r--r--drivers/scsi/scsi_lib_dma.c50
1 files changed, 50 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_lib_dma.c b/drivers/scsi/scsi_lib_dma.c
new file mode 100644
index 000000000000..ac6855cd2657
--- /dev/null
+++ b/drivers/scsi/scsi_lib_dma.c
@@ -0,0 +1,50 @@
+/*
+ * SCSI library functions depending on DMA
+ */
+
+#include <linux/blkdev.h>
+#include <linux/device.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->shost_gendev.parent;
+
+ 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->shost_gendev.parent;
+
+ dma_unmap_sg(dev, scsi_sglist(cmd), scsi_sg_count(cmd),
+ cmd->sc_data_direction);
+ }
+}
+EXPORT_SYMBOL(scsi_dma_unmap);