IB/iser: Support up to 16MB data transfer in a single command

Maximum supported IO size is 8MB for the iSER driver. The current value is
limited by the ISCSI_ISER_MAX_SG_TABLESIZE macro. But the driver is able
to handle 16MB IOs without any significant changes. Increasing this limit
can be useful for the storage arrays which are fine tuned for IOs larger
than 8 MB.

This commit allows to configure maximum IO size up to 16MB using the
max_sectors module parameter.

Link: https://lore.kernel.org/r/20190912103534.18210-1-sergeygo@mellanox.com
Signed-off-by: Sergey Gorenko <sergeygo@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.h b/drivers/infiniband/ulp/iser/iscsi_iser.h
index 39bf213444cbb509ccd3c2214c526cb6c8e3ac9a..52ce63592dcf260650f3e175f9edb74a9e2406ba 100644 (file)
--- a/drivers/infiniband/ulp/iser/iscsi_iser.h
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.h
@@ -102,9 +102,10 @@
 
 /* Default support is 512KB I/O size */
 #define ISER_DEF_MAX_SECTORS           1024
-#define ISCSI_ISER_DEF_SG_TABLESIZE    ((ISER_DEF_MAX_SECTORS * 512) >> SHIFT_4K)
-/* Maximum support is 8MB I/O size */
-#define ISCSI_ISER_MAX_SG_TABLESIZE    ((16384 * 512) >> SHIFT_4K)
+#define ISCSI_ISER_DEF_SG_TABLESIZE                                            \
+       ((ISER_DEF_MAX_SECTORS * SECTOR_SIZE) >> SHIFT_4K)
+/* Maximum support is 16MB I/O size */
+#define ISCSI_ISER_MAX_SG_TABLESIZE    ((32768 * SECTOR_SIZE) >> SHIFT_4K)
 
 #define ISER_DEF_XMIT_CMDS_DEFAULT             512
 #if ISCSI_DEF_XMIT_CMDS_MAX > ISER_DEF_XMIT_CMDS_DEFAULT