Commit 7689e82e authored by Cornelia Huck's avatar Cornelia Huck Committed by James Bottomley
Browse files

[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: default avatarCornelia 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: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@SteelEye.com>
parent 6d877688

drivers/scsi/Kconfig

+5 −0
Original line number Diff line number Diff line
@@ -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

drivers/scsi/Makefile

+3 −3
Original line number Diff line number Diff line
@@ -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

drivers/scsi/scsi_lib.c

+0 −38
Original line number Diff line number Diff line
@@ -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);

drivers/scsi/scsi_lib_dma.c

0 → 100644
+50 −0
Original line number Diff line number Diff line 
/*

 * 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);

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