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-rw-r--r--drivers/scsi/sun3_NCR5380.c58
1 files changed, 0 insertions, 58 deletions
diff --git a/drivers/scsi/sun3_NCR5380.c b/drivers/scsi/sun3_NCR5380.c
index f3cffdf5a011..7e12a2e4e0a3 100644
--- a/drivers/scsi/sun3_NCR5380.c
+++ b/drivers/scsi/sun3_NCR5380.c
@@ -49,13 +49,6 @@
* inside the execution of NCR5380_intr(), leading to recursive
* calls.
*
- * - I've added a function merge_contiguous_buffers() that tries to
- * merge scatter-gather buffers that are located at contiguous
- * physical addresses and can be processed with the same DMA setup.
- * Since most scatter-gather operations work on a page (4K) of
- * 4 buffers (1K), in more than 90% of all cases three interrupts and
- * DMA setup actions are saved.
- *
* - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA
* and USLEEP, because these were messing up readability and will never be
* needed for Atari SCSI.
@@ -460,47 +453,6 @@ static void free_all_tags( void )
/*
- * Function: void merge_contiguous_buffers(struct scsi_cmnd *cmd)
- *
- * Purpose: Try to merge several scatter-gather requests into one DMA
- * transfer. This is possible if the scatter buffers lie on
- * physical contiguous addresses.
- *
- * Parameters: struct scsi_cmnd *cmd
- * The command to work on. The first scatter buffer's data are
- * assumed to be already transferred into ptr/this_residual.
- */
-
-static void merge_contiguous_buffers(struct scsi_cmnd *cmd)
-{
- unsigned long endaddr;
-#if (NDEBUG & NDEBUG_MERGING)
- unsigned long oldlen = cmd->SCp.this_residual;
- int cnt = 1;
-#endif
-
- for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1;
- cmd->SCp.buffers_residual &&
- virt_to_phys(SGADDR(&(cmd->SCp.buffer[1]))) == endaddr; ) {
-
- MER_PRINTK("VTOP(%p) == %08lx -> merging\n",
- SGADDR(&(cmd->SCp.buffer[1])), endaddr);
-#if (NDEBUG & NDEBUG_MERGING)
- ++cnt;
-#endif
- ++cmd->SCp.buffer;
- --cmd->SCp.buffers_residual;
- cmd->SCp.this_residual += cmd->SCp.buffer->length;
- endaddr += cmd->SCp.buffer->length;
- }
-#if (NDEBUG & NDEBUG_MERGING)
- if (oldlen != cmd->SCp.this_residual)
- MER_PRINTK("merged %d buffers from %p, new length %08x\n",
- cnt, cmd->SCp.ptr, cmd->SCp.this_residual);
-#endif
-}
-
-/*
* Function : void initialize_SCp(struct scsi_cmnd *cmd)
*
* Purpose : initialize the saved data pointers for cmd to point to the
@@ -521,11 +473,6 @@ static __inline__ void initialize_SCp(struct scsi_cmnd *cmd)
cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
cmd->SCp.ptr = (char *) SGADDR(cmd->SCp.buffer);
cmd->SCp.this_residual = cmd->SCp.buffer->length;
-
- /* ++roman: Try to merge some scatter-buffers if they are at
- * contiguous physical addresses.
- */
-// merge_contiguous_buffers( cmd );
} else {
cmd->SCp.buffer = NULL;
cmd->SCp.buffers_residual = 0;
@@ -2076,11 +2023,6 @@ static void NCR5380_information_transfer (struct Scsi_Host *instance)
--cmd->SCp.buffers_residual;
cmd->SCp.this_residual = cmd->SCp.buffer->length;
cmd->SCp.ptr = SGADDR(cmd->SCp.buffer);
-
- /* ++roman: Try to merge some scatter-buffers if
- * they are at contiguous physical addresses.
- */
-// merge_contiguous_buffers( cmd );
INF_PRINTK("scsi%d: %d bytes and %d buffers left\n",
HOSTNO, cmd->SCp.this_residual,
cmd->SCp.buffers_residual);