2 files changed, 25 insertions, 10 deletions

diff --git a/drivers/scsi/megaraid/megaraid_sas.c b/drivers/scsi/megaraid/megaraid_sas.c
index 4014225300a..ffd1390b155 100644
--- a/drivers/scsi/megaraid/megaraid_sas.c
+++ b/drivers/scsi/megaraid/megaraid_sas.c
@@ -488,12 +488,13 @@ megasas_make_sgl64(struct megasas_instance *instance, struct scsi_cmnd *scp,
 
  /**
  * megasas_get_frame_count - Computes the number of frames
+ * @frame_type          : type of frame- io or pthru frame
  * @sge_count           : number of sg elements
  *
  * Returns the number of frames required for numnber of sge's (sge_count)
  */
 
-static u32 megasas_get_frame_count(u8 sge_count)
+static u32 megasas_get_frame_count(u8 sge_count, u8 frame_type)
 {
         int num_cnt;
         int sge_bytes;
@@ -504,13 +505,22 @@ static u32 megasas_get_frame_count(u8 sge_count)
             sizeof(struct megasas_sge32);
 
         /*
-        * Main frame can contain 2 SGEs for 64-bit SGLs and
-        * 3 SGEs for 32-bit SGLs
-        */
-        if (IS_DMA64)
-                num_cnt = sge_count - 2;
-        else
-                num_cnt = sge_count - 3;
+         * Main frame can contain 2 SGEs for 64-bit SGLs and
+         * 3 SGEs for 32-bit SGLs for ldio &
+         * 1 SGEs for 64-bit SGLs and
+         * 2 SGEs for 32-bit SGLs for pthru frame
+         */
+        if (unlikely(frame_type == PTHRU_FRAME)) {
+                if (IS_DMA64)
+                        num_cnt = sge_count - 1;
+                else
+                        num_cnt = sge_count - 2;
+        } else {
+                if (IS_DMA64)
+                        num_cnt = sge_count - 2;
+                else
+                        num_cnt = sge_count - 3;
+        }
 
         if(num_cnt>0){
                 sge_bytes = sge_sz * num_cnt;
@@ -592,7 +602,8 @@ megasas_build_dcdb(struct megasas_instance *instance, struct scsi_cmnd *scp,
          * Compute the total number of frames this command consumes. FW uses
          * this number to pull sufficient number of frames from host memory.
          */
-        cmd->frame_count = megasas_get_frame_count(pthru->sge_count);
+        cmd->frame_count = megasas_get_frame_count(pthru->sge_count,
+                                                        PTHRU_FRAME);
 
         return cmd->frame_count;
 }
@@ -709,7 +720,7 @@ megasas_build_ldio(struct megasas_instance *instance, struct scsi_cmnd *scp,
          * Compute the total number of frames this command consumes. FW uses
          * this number to pull sufficient number of frames from host memory.
          */
-        cmd->frame_count = megasas_get_frame_count(ldio->sge_count);
+        cmd->frame_count = megasas_get_frame_count(ldio->sge_count, IO_FRAME);
 
         return cmd->frame_count;
 }
diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h
index 6466bdf548c..fbbfe2ea049 100644
--- a/drivers/scsi/megaraid/megaraid_sas.h
+++ b/drivers/scsi/megaraid/megaraid_sas.h
@@ -542,6 +542,10 @@ struct megasas_ctrl_info {
 
 #define MEGASAS_FW_BUSY                         1
 
+/* Frame Type */
+#define IO_FRAME                                0
+#define PTHRU_FRAME                             1
+
 /*
  * When SCSI mid-layer calls driver's reset routine, driver waits for
  * MEGASAS_RESET_WAIT_TIME seconds for all outstanding IO to complete. Note