[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>

diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index 874cfee2935802e630efd628f87f1227e7046c27..6ac3873e4d7331d1a0304ae401edd1a361c3c4e7 100644 (file)
--- a/drivers/scsi/Kconfig
+++ b/drivers/scsi/Kconfig
@@ -10,6 +10,7 @@ config RAID_ATTRS
 config SCSI
        tristate "SCSI device support"
        depends on BLOCK
+       select SCSI_DMA if HAS_DMA
        ---help---
          If you want to use a SCSI hard disk, SCSI tape drive, SCSI CD-ROM or
          any other SCSI device under Linux, say Y and make sure that you know
@@ -29,6 +30,10 @@ config SCSI
          However, do not compile this as a module if your root file system
          (the one containing the directory /) is located on a SCSI device.
 
+config SCSI_DMA
+       bool
+       default n
+
 config SCSI_TGT
        tristate "SCSI target support"
        depends on SCSI && EXPERIMENTAL

diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile
index cbc2e2ba54124815e6f0fd3eb75abbd185ce9fc1..0f8689557158563d14507cf682b0917bd5c59339 100644 (file)
--- a/drivers/scsi/Makefile
+++ b/drivers/scsi/Makefile
@@ -148,9 +148,9 @@ obj-$(CONFIG_SCSI_DEBUG)    += scsi_debug.o
 obj-$(CONFIG_SCSI_WAIT_SCAN)   += scsi_wait_scan.o
 
 scsi_mod-y                     += scsi.o hosts.o scsi_ioctl.o constants.o \
-                                  scsicam.o scsi_error.o scsi_lib.o \
-                                  scsi_scan.o scsi_sysfs.o \
-                                  scsi_devinfo.o
+                                  scsicam.o scsi_error.o scsi_lib.o
+scsi_mod-$(CONFIG_SCSI_DMA)    += scsi_lib_dma.o
+scsi_mod-y                     += scsi_scan.o scsi_sysfs.o scsi_devinfo.o
 scsi_mod-$(CONFIG_SCSI_NETLINK)        += scsi_netlink.o
 scsi_mod-$(CONFIG_SYSCTL)      += scsi_sysctl.o
 scsi_mod-$(CONFIG_SCSI_PROC_FS)        += scsi_proc.o

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 70454b4e8485cf929c3a70da7ee3732f8834c05e..1f5a07bf2a7535e439300b4daa51f898983973ef 100644 (file)
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2290,41 +2290,3 @@ void scsi_kunmap_atomic_sg(void *virt)
        kunmap_atomic(virt, KM_BIO_SRC_IRQ);
 }
 EXPORT_SYMBOL(scsi_kunmap_atomic_sg);
-
-/**
- * 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);

diff --git a/drivers/scsi/scsi_lib_dma.c b/drivers/scsi/scsi_lib_dma.c
new file mode 100644 (file)
index 0000000..ac6855c
--- /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);