drivers/scsi/scsi_debug.c: resolve sg buffer const-ness issue
do_device_access() takes a separate parameter to indicate the direction of
data transfer, which it used to use to select the appropriate function out
of sg_pcopy_{to,from}_buffer(). However these two functions now have
So this patch makes it bypass these wrappers and call the underlying
function sg_copy_buffer() directly; this has the same calling style as
do_device_access() i.e. a separate direction-of-transfer parameter and no
pointers-to-const, so skipping the wrappers not only eliminates the
warning, it also make the code simpler :)
[akpm@linux-foundation.org: fix very broken build]
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 1f8e2dc..30268bb 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -2363,17 +2363,13 @@
u64 block, rest = 0;
struct scsi_data_buffer *sdb;
enum dma_data_direction dir;
- size_t (*func)(struct scatterlist *, unsigned int, void *, size_t,
- off_t);
if (do_write) {
sdb = scsi_out(scmd);
dir = DMA_TO_DEVICE;
- func = sg_pcopy_to_buffer;
} else {
sdb = scsi_in(scmd);
dir = DMA_FROM_DEVICE;
- func = sg_pcopy_from_buffer;
}
if (!sdb->length)
@@ -2385,16 +2381,16 @@
if (block + num > sdebug_store_sectors)
rest = block + num - sdebug_store_sectors;
- ret = func(sdb->table.sgl, sdb->table.nents,
+ ret = sg_copy_buffer(sdb->table.sgl, sdb->table.nents,
fake_storep + (block * scsi_debug_sector_size),
- (num - rest) * scsi_debug_sector_size, 0);
+ (num - rest) * scsi_debug_sector_size, 0, do_write);
if (ret != (num - rest) * scsi_debug_sector_size)
return ret;
if (rest) {
- ret += func(sdb->table.sgl, sdb->table.nents,
+ ret += sg_copy_buffer(sdb->table.sgl, sdb->table.nents,
fake_storep, rest * scsi_debug_sector_size,
- (num - rest) * scsi_debug_sector_size);
+ (num - rest) * scsi_debug_sector_size, do_write);
}
return ret;
diff --git a/include/linux/scatterlist.h b/include/linux/scatterlist.h
index 505d048..9b1ef0c 100644
--- a/include/linux/scatterlist.h
+++ b/include/linux/scatterlist.h
@@ -265,6 +265,9 @@
unsigned long offset, unsigned long size,
gfp_t gfp_mask);
+size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents, void *buf,
+ size_t buflen, off_t skip, bool to_buffer);
+
size_t sg_copy_from_buffer(struct scatterlist *sgl, unsigned int nents,
const void *buf, size_t buflen);
size_t sg_copy_to_buffer(struct scatterlist *sgl, unsigned int nents,
diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index 317b62c..d105a9f 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -650,9 +650,8 @@
* Returns the number of copied bytes.
*
**/
-static size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents,
- void *buf, size_t buflen, off_t skip,
- bool to_buffer)
+size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents, void *buf,
+ size_t buflen, off_t skip, bool to_buffer)
{
unsigned int offset = 0;
struct sg_mapping_iter miter;
@@ -689,6 +688,7 @@
local_irq_restore(flags);
return offset;
}
+EXPORT_SYMBOL(sg_copy_buffer);
/**
* sg_copy_from_buffer - Copy from a linear buffer to an SG list
