5 files changed, 60 insertions, 7 deletions

diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c
index 169cc3e75018..0720bb46589f 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.c
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.c
@@ -93,6 +93,10 @@ static unsigned int iscsi_max_lun = 512;
 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
 MODULE_PARM_DESC(max_lun, "Max LUNs to allow per session (default:512");
 
+unsigned int iser_max_sectors = ISER_DEF_MAX_SECTORS;
+module_param_named(max_sectors, iser_max_sectors, uint, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(max_sectors, "Max number of sectors in a single scsi command (default:1024");
+
 bool iser_pi_enable = false;
 module_param_named(pi_enable, iser_pi_enable, bool, S_IRUGO);
 MODULE_PARM_DESC(pi_enable, "Enable T10-PI offload support (default:disabled)");
@@ -625,6 +629,8 @@ iscsi_iser_session_create(struct iscsi_endpoint *ep,
         if (ep) {
                 iser_conn = ep->dd_data;
                 max_cmds = iser_conn->max_cmds;
+                shost->sg_tablesize = iser_conn->scsi_sg_tablesize;
+                shost->max_sectors = iser_conn->scsi_max_sectors;
 
                 mutex_lock(&iser_conn->state_mutex);
                 if (iser_conn->state != ISER_CONN_UP) {
@@ -966,8 +972,8 @@ static struct scsi_host_template iscsi_iser_sht = {
         .name                   = "iSCSI Initiator over iSER",
         .queuecommand           = iscsi_queuecommand,
         .change_queue_depth     = scsi_change_queue_depth,
-        .sg_tablesize           = ISCSI_ISER_SG_TABLESIZE,
-        .max_sectors            = 1024,
+        .sg_tablesize           = ISCSI_ISER_DEF_SG_TABLESIZE,
+        .max_sectors            = ISER_DEF_MAX_SECTORS,
         .cmd_per_lun            = ISER_DEF_CMD_PER_LUN,
         .eh_abort_handler       = iscsi_eh_abort,
         .eh_device_reset_handler= iscsi_eh_device_reset,
diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.h b/drivers/infiniband/ulp/iser/iscsi_iser.h
index e9ebe0b2263d..0bdd7e77e5db 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.h
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.h
@@ -98,8 +98,13 @@
 #define SHIFT_4K        12
 #define SIZE_4K (1ULL << SHIFT_4K)
 #define MASK_4K (~(SIZE_4K-1))
-                                        /* support up to 512KB in one RDMA */
-#define ISCSI_ISER_SG_TABLESIZE         (0x80000 >> SHIFT_4K)
+
+/* 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 ISER_DEF_XMIT_CMDS_DEFAULT              512
 #if ISCSI_DEF_XMIT_CMDS_MAX > ISER_DEF_XMIT_CMDS_DEFAULT
         #define ISER_DEF_XMIT_CMDS_MAX          ISCSI_DEF_XMIT_CMDS_MAX
@@ -504,6 +509,8 @@ struct ib_conn {
  * @rx_desc_head:     head of rx_descs cyclic buffer
  * @rx_descs:         rx buffers array (cyclic buffer)
  * @num_rx_descs:     number of rx descriptors
+ * @scsi_sg_tablesize: scsi host sg_tablesize
+ * @scsi_max_sectors: scsi host max sectors
  */
 struct iser_conn {
         struct ib_conn               ib_conn;
@@ -528,6 +535,8 @@ struct iser_conn {
         unsigned int                 rx_desc_head;
         struct iser_rx_desc          *rx_descs;
         u32                          num_rx_descs;
+        unsigned short               scsi_sg_tablesize;
+        unsigned int                 scsi_max_sectors;
 };
 
 /**
@@ -583,6 +592,7 @@ extern struct iser_global ig;
 extern int iser_debug_level;
 extern bool iser_pi_enable;
 extern int iser_pi_guard;
+extern unsigned int iser_max_sectors;
 
 int iser_assign_reg_ops(struct iser_device *device);
 
diff --git a/drivers/infiniband/ulp/iser/iser_initiator.c b/drivers/infiniband/ulp/iser/iser_initiator.c
index f1200f27b6a7..0b1f3b54a0c1 100644
--- a/drivers/infiniband/ulp/iser/iser_initiator.c
+++ b/drivers/infiniband/ulp/iser/iser_initiator.c
@@ -259,7 +259,7 @@ int iser_alloc_rx_descriptors(struct iser_conn *iser_conn,
         iser_conn->min_posted_rx = iser_conn->qp_max_recv_dtos >> 2;
 
         if (device->reg_ops->alloc_reg_res(ib_conn, session->scsi_cmds_max,
-                                           ISCSI_ISER_SG_TABLESIZE + 1))
+                                           iser_conn->scsi_sg_tablesize))
                 goto create_rdma_reg_res_failed;
 
         if (iser_alloc_login_buf(iser_conn))
diff --git a/drivers/infiniband/ulp/iser/iser_memory.c b/drivers/infiniband/ulp/iser/iser_memory.c
index b1261d5fbb9b..384fd0a49cca 100644
--- a/drivers/infiniband/ulp/iser/iser_memory.c
+++ b/drivers/infiniband/ulp/iser/iser_memory.c
@@ -363,7 +363,8 @@ static int iser_sg_to_page_vec(struct iser_data_buf *data,
  * consecutive SG elements are actually fragments of the same physcial page.
  */
 static int iser_data_buf_aligned_len(struct iser_data_buf *data,
-                                      struct ib_device *ibdev)
+                                     struct ib_device *ibdev,
+                                     unsigned sg_tablesize)
 {
         struct scatterlist *sg, *sgl, *next_sg = NULL;
         u64 start_addr, end_addr;
@@ -375,6 +376,14 @@ static int iser_data_buf_aligned_len(struct iser_data_buf *data,
         sgl = data->sg;
         start_addr  = ib_sg_dma_address(ibdev, sgl);
 
+        if (unlikely(sgl[0].offset &&
+                     data->data_len >= sg_tablesize * PAGE_SIZE)) {
+                iser_dbg("can't register length %lx with offset %x "
+                         "fall to bounce buffer\n", data->data_len,
+                         sgl[0].offset);
+                return 0;
+        }
+
         for_each_sg(sgl, sg, data->dma_nents, i) {
                 if (start_check && !IS_4K_ALIGNED(start_addr))
                         break;
@@ -790,7 +799,8 @@ iser_handle_unaligned_buf(struct iscsi_iser_task *task,
         struct iser_device *device = iser_conn->ib_conn.device;
         int err, aligned_len;
 
-        aligned_len = iser_data_buf_aligned_len(mem, device->ib_device);
+        aligned_len = iser_data_buf_aligned_len(mem, device->ib_device,
+                                                iser_conn->scsi_sg_tablesize);
         if (aligned_len != mem->dma_nents) {
                 err = fall_to_bounce_buf(task, mem, dir);
                 if (err)
diff --git a/drivers/infiniband/ulp/iser/iser_verbs.c b/drivers/infiniband/ulp/iser/iser_verbs.c
index 0ade0e876c79..187c7125a4b9 100644
--- a/drivers/infiniband/ulp/iser/iser_verbs.c
+++ b/drivers/infiniband/ulp/iser/iser_verbs.c
@@ -756,6 +756,31 @@ static void iser_connect_error(struct rdma_cm_id *cma_id)
         iser_conn->state = ISER_CONN_TERMINATING;
 }
 
+static void
+iser_calc_scsi_params(struct iser_conn *iser_conn,
+                      unsigned int max_sectors)
+{
+        struct iser_device *device = iser_conn->ib_conn.device;
+        unsigned short sg_tablesize, sup_sg_tablesize;
+
+        sg_tablesize = DIV_ROUND_UP(max_sectors * 512, SIZE_4K);
+        sup_sg_tablesize = min_t(unsigned, ISCSI_ISER_MAX_SG_TABLESIZE,
+                                 device->dev_attr.max_fast_reg_page_list_len);
+
+        if (sg_tablesize > sup_sg_tablesize) {
+                sg_tablesize = sup_sg_tablesize;
+                iser_conn->scsi_max_sectors = sg_tablesize * SIZE_4K / 512;
+        } else {
+                iser_conn->scsi_max_sectors = max_sectors;
+        }
+
+        iser_conn->scsi_sg_tablesize = sg_tablesize;
+
+        iser_dbg("iser_conn %p, sg_tablesize %u, max_sectors %u\n",
+                 iser_conn, iser_conn->scsi_sg_tablesize,
+                 iser_conn->scsi_max_sectors);
+}
+
 /**
  * Called with state mutex held
  **/
@@ -794,6 +819,8 @@ static void iser_addr_handler(struct rdma_cm_id *cma_id)
                 }