IB/iser: set block queue_virt_boundary

The block layer can reliably guarantee that SG lists won't
contain gaps (page unaligned) if a driver set the queue
virt_boundary.

With this setting the block layer will:
- refuse merges if bios are not aligned to the virtual boundary
- split bios/requests that are not aligned to the virtual boundary
- or, bounce buffer SG_IOs that are not aligned to the virtual boundary

Since iser is working in 4K page size, set the virt_boundary to
4K pages. With this setting, we can now safely remove the bounce
buffering logic in iser.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 1 insertions, 6 deletions

diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.h b/drivers/infiniband/ulp/iser/iscsi_iser.h
index a5edd6ede692..d8bbad9eb59b 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.h
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.h
@@ -227,18 +227,13 @@ enum iser_data_dir {
  * @size:         num entries of this sg
  * @data_len:     total beffer byte len
  * @dma_nents:    returned by dma_map_sg
- * @orig_sg:      pointer to the original sg list (in case
- *                we used a copy)
- * @orig_size:    num entris of orig sg list
  */
 struct iser_data_buf {
 	struct scatterlist *sg;
 	unsigned int       size;
 	unsigned long      data_len;
 	unsigned int       dma_nents;
-	struct scatterlist *orig_sg;
-	unsigned int       orig_size;
-  };
+};
 
 /* fwd declarations */
 struct iser_device;