cxgb4: fix overflow in collecting IBQ and OBQ dump

Destination buffer already has offset added.  So, don't add offset
again.

Fetch actual size of configured OBQ from hardware, instead of using
hardcoded value.

Fixes: 7c075ce2 ("cxgb4: collect IBQ and OBQ dumps")
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c

@@ -146,8 +146,7 @@ static int cudbg_read_cim_ibq(struct cudbg_init *pdbg_init,
 
 	/* t4_read_cim_ibq will return no. of read words or error */
 	no_of_read_words = t4_read_cim_ibq(padap, qid,
-					   (u32 *)((u32 *)temp_buff.data +
-					   temp_buff.offset), qsize);
+					   (u32 *)temp_buff.data, qsize);
 	/* no_of_read_words is less than or equal to 0 means error */
 	if (no_of_read_words <= 0) {
 		if (!no_of_read_words)
@@ -204,6 +203,17 @@ int cudbg_collect_cim_ibq_ncsi(struct cudbg_init *pdbg_init,
 	return cudbg_read_cim_ibq(pdbg_init, dbg_buff, cudbg_err, 5);
 }
 
+u32 cudbg_cim_obq_size(struct adapter *padap, int qid)
+{
+	u32 value;
+
+	t4_write_reg(padap, CIM_QUEUE_CONFIG_REF_A, OBQSELECT_F |
+		     QUENUMSELECT_V(qid));
+	value = t4_read_reg(padap, CIM_QUEUE_CONFIG_CTRL_A);
+	value = CIMQSIZE_G(value) * 64; /* size in number of words */
+	return value * sizeof(u32);
+}
+
 static int cudbg_read_cim_obq(struct cudbg_init *pdbg_init,
 			      struct cudbg_buffer *dbg_buff,
 			      struct cudbg_error *cudbg_err, int qid)
@@ -214,15 +224,14 @@ static int cudbg_read_cim_obq(struct cudbg_init *pdbg_init,
 	u32 qsize;
 
 	/* collect CIM OBQ */
-	qsize =  6 * CIM_OBQ_SIZE * 4 *  sizeof(u32);
+	qsize =  cudbg_cim_obq_size(padap, qid);
 	rc = cudbg_get_buff(dbg_buff, qsize, &temp_buff);
 	if (rc)
 		return rc;
 
 	/* t4_read_cim_obq will return no. of read words or error */
 	no_of_read_words = t4_read_cim_obq(padap, qid,
-					   (u32 *)((u32 *)temp_buff.data +
-					   temp_buff.offset), qsize);
+					   (u32 *)temp_buff.data, qsize);
 	/* no_of_read_words is less than or equal to 0 means error */
 	if (no_of_read_words <= 0) {
 		if (!no_of_read_words)
@@ -233,7 +242,6 @@ static int cudbg_read_cim_obq(struct cudbg_init *pdbg_init,
 		cudbg_put_buff(&temp_buff, dbg_buff);
 		return rc;
 	}
-	temp_buff.size = no_of_read_words * 4;
 	cudbg_write_and_release_buff(&temp_buff, dbg_buff);
 	return rc;
 }

drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.h

@@ -100,4 +100,5 @@ int cudbg_collect_hma_indirect(struct cudbg_init *pdbg_init,
 struct cudbg_entity_hdr *cudbg_get_entity_hdr(void *outbuf, int i);
 void cudbg_align_debug_buffer(struct cudbg_buffer *dbg_buff,
 			      struct cudbg_entity_hdr *entity_hdr);
+u32 cudbg_cim_obq_size(struct adapter *padap, int qid);
 #endif /* __CUDBG_LIB_H__ */

drivers/net/ethernet/chelsio/cxgb4/cxgb4_cudbg.c

@@ -82,14 +82,28 @@ static u32 cxgb4_get_entity_length(struct adapter *adap, u32 entity)
 		len = CIM_IBQ_SIZE * 4 * sizeof(u32);
 		break;
 	case CUDBG_CIM_OBQ_ULP0:
+		len = cudbg_cim_obq_size(adap, 0);
+		break;
 	case CUDBG_CIM_OBQ_ULP1:
+		len = cudbg_cim_obq_size(adap, 1);
+		break;
 	case CUDBG_CIM_OBQ_ULP2:
+		len = cudbg_cim_obq_size(adap, 2);
+		break;
 	case CUDBG_CIM_OBQ_ULP3:
+		len = cudbg_cim_obq_size(adap, 3);
+		break;
 	case CUDBG_CIM_OBQ_SGE:
+		len = cudbg_cim_obq_size(adap, 4);
+		break;
 	case CUDBG_CIM_OBQ_NCSI:
+		len = cudbg_cim_obq_size(adap, 5);
+		break;
 	case CUDBG_CIM_OBQ_RXQ0:
+		len = cudbg_cim_obq_size(adap, 6);
+		break;
 	case CUDBG_CIM_OBQ_RXQ1:
-		len = 6 * CIM_OBQ_SIZE * 4 * sizeof(u32);
+		len = cudbg_cim_obq_size(adap, 7);
 		break;
 	case CUDBG_EDC0:
 		value = t4_read_reg(adap, MA_TARGET_MEM_ENABLE_A);