Merge branch 'for-linus' of git://git.kernel.dk/data/git/linux-2.6-block

* 'for-linus' of git://git.kernel.dk/data/git/linux-2.6-block:
  [SCSI] Remove full sg table memset()
  [SCSI] ide-scsi: remove usage of sg_last()
  Fix loop terminating conditions in fill_sg().
  [BLOCK] Clear sg entry before filling in blk_rq_map_sg()
  IA64: iommu uses sg_next with an invalid sg element
  cciss: disable DMA refetch on Smart Array P600
  swiotlb: fix map_sg failure handling
  SPARC64: fix iommu sg chaining
  [SCSI] ide-scsi: use scsi_sg_count() instead of ->use_sg

3 files changed, 12 insertions, 9 deletions

diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index ca56a0e5cd5..7c2cfde08f1 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -3076,15 +3076,20 @@ static int cciss_pci_init(ctlr_info_t *c, struct pci_dev *pdev)
 	}
 #endif
 
-	/* Disabling DMA prefetch for the P600
-	 * An ASIC bug may result in a prefetch beyond
-	 * physical memory.
+	/* Disabling DMA prefetch and refetch for the P600.
+	 * An ASIC bug may result in accesses to invalid memory addresses.
+	 * We've disabled prefetch for some time now. Testing with XEN
+	 * kernels revealed a bug in the refetch if dom0 resides on a P600.
 	 */
 	if(board_id == 0x3225103C) {
 		__u32 dma_prefetch;
+		__u32 dma_refetch;
 		dma_prefetch = readl(c->vaddr + I2O_DMA1_CFG);
 		dma_prefetch |= 0x8000;
 		writel(dma_prefetch, c->vaddr + I2O_DMA1_CFG);
+		pci_read_config_dword(pdev, PCI_COMMAND_PARITY, &dma_refetch);
+		dma_refetch |= 0x1;
+		pci_write_config_dword(pdev, PCI_COMMAND_PARITY, dma_refetch);
 	}
 
 #ifdef CCISS_DEBUG
diff --git a/drivers/scsi/ide-scsi.c b/drivers/scsi/ide-scsi.c
index d297f64cd43..fa7ba64483f 100644
--- a/drivers/scsi/ide-scsi.c
+++ b/drivers/scsi/ide-scsi.c
@@ -70,7 +70,7 @@ typedef struct idescsi_pc_s {
 	u8 *buffer;				/* Data buffer */
 	u8 *current_position;			/* Pointer into the above buffer */
 	struct scatterlist *sg;			/* Scatter gather table */
-	struct scatterlist *last_sg;		/* Last sg element */
+	unsigned int sg_cnt;			/* Number of entries in sg */
 	int b_count;				/* Bytes transferred from current entry */
 	struct scsi_cmnd *scsi_cmd;		/* SCSI command */
 	void (*done)(struct scsi_cmnd *);	/* Scsi completion routine */
@@ -192,7 +192,7 @@ static void idescsi_input_buffers (ide_drive_t *drive, idescsi_pc_t *pc, unsigne
 		}
 		bcount -= count; pc->b_count += count;
 		if (pc->b_count == pc->sg->length) {
-			if (pc->sg == pc->last_sg)
+			if (!--pc->sg_cnt)
 				break;
 			pc->sg = sg_next(pc->sg);
 			pc->b_count = 0;
@@ -229,7 +229,7 @@ static void idescsi_output_buffers (ide_drive_t *drive, idescsi_pc_t *pc, unsign
 		}
 		bcount -= count; pc->b_count += count;
 		if (pc->b_count == pc->sg->length) {
-			if (pc->sg == pc->last_sg)
+			if (!--pc->sg_cnt)
 				break;
 			pc->sg = sg_next(pc->sg);
 			pc->b_count = 0;
@@ -807,7 +807,7 @@ static int idescsi_queue (struct scsi_cmnd *cmd,
 	memcpy (pc->c, cmd->cmnd, cmd->cmd_len);
 	pc->buffer = NULL;
 	pc->sg = scsi_sglist(cmd);
-	pc->last_sg = sg_last(pc->sg, cmd->use_sg);
+	pc->sg_cnt = scsi_sg_count(cmd);
 	pc->b_count = 0;
 	pc->request_transfer = pc->buffer_size = scsi_bufflen(cmd);
 	pc->scsi_cmd = cmd;
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index aac8a02cbe8..0c86be71bb3 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -764,8 +764,6 @@ struct scatterlist *scsi_alloc_sgtable(struct scsi_cmnd *cmd, gfp_t gfp_mask)
 		if (unlikely(!sgl))
 			goto enomem;
 
-		memset(sgl, 0, sizeof(*sgl) * sgp->size);
-
 		/*
 		 * first loop through, set initial index and return value
 		 */