From c59be52d4725bf8d95bed46907b515b3bed88074 Mon Sep 17 00:00:00 2001
From: Orhan K AKYILDIZ <oka@codeaurora.org>
Date: Wed, 19 Apr 2017 21:21:45 -0700
Subject: [PATCH] qcacmn: Add debug for TSO seg double-free

Add TSO segment debug code, in a featurized way, so that
when disabled, it will tolerate redundant returns to the internal
pool and when enabled, it will check sanity on free, and record a
history of last 16 actions on the segment in the object.

Goes with the corresponding cld3 component counterpart.

Change-Id: Ifee2ceae940043031e4861d0e4f5d19a51262229
CRs-Fixed: 2036665
---
 qdf/inc/qdf_trace.h      | 56 ++++++++++++++++++++++++++++++++++++++++
 qdf/inc/qdf_types.h      | 30 +++++++++++++++++++++
 qdf/linux/src/qdf_nbuf.c |  1 +
 3 files changed, 87 insertions(+)

diff --git a/qdf/inc/qdf_trace.h b/qdf/inc/qdf_trace.h
index 454f385e73..ae6ba2c311 100644
--- a/qdf/inc/qdf_trace.h
+++ b/qdf/inc/qdf_trace.h
@@ -476,6 +476,62 @@ void __printf(3, 4) qdf_snprintf(char *str_buffer, unsigned int size,
 		  char *str_format, ...);
 
 #define QDF_SNPRINTF qdf_snprintf
+
+#ifdef TSOSEG_DEBUG
+static inline
+int qdf_tso_seg_dbg_record(struct qdf_tso_seg_elem_t *tsoseg,
+			   uint16_t caller)
+{
+	int rc = -1;
+
+	if (tsoseg != NULL) {
+		tsoseg->dbg.cur++;  tsoseg->dbg.cur &= 0x0f;
+		tsoseg->dbg.history[tsoseg->dbg.cur] = caller;
+		rc = tsoseg->dbg.cur;
+	}
+	return rc;
+};
+static inline void qdf_tso_seg_dbg_bug(char *msg)
+{
+	qdf_print(msg);
+	QDF_BUG(0);
+};
+
+static inline void
+qdf_tso_seg_dbg_setowner(struct qdf_tso_seg_elem_t *tsoseg, void *owner)
+{
+	tsoseg->dbg.txdesc = owner;
+};
+
+static inline void
+qdf_tso_seg_dbg_zero(struct qdf_tso_seg_elem_t *tsoseg)
+{
+	memset(tsoseg, 0, offsetof(struct qdf_tso_seg_elem_t, dbg));
+	return;
+};
+
+#else
+static inline
+int qdf_tso_seg_dbg_record(struct qdf_tso_seg_elem_t *tsoseg,
+			   uint16_t caller)
+{
+	return 0;
+};
+static inline void qdf_tso_seg_dbg_bug(char *msg)
+{
+};
+static inline void
+qdf_tso_seg_dbg_setowner(struct qdf_tso_seg_elem_t *tsoseg, void *owner)
+{
+};
+static inline int
+qdf_tso_seg_dbg_zero(struct qdf_tso_seg_elem_t *tsoseg)
+{
+	memset(tsoseg, 0, sizeof(struct qdf_tso_seg_elem_t));
+	return 0;
+};
+
+#endif /* TSOSEG_DEBUG */
 #else
 
 #define DPTRACE(x)
diff --git a/qdf/inc/qdf_types.h b/qdf/inc/qdf_types.h
index 10304506de..d7545b113e 100644
--- a/qdf/inc/qdf_types.h
+++ b/qdf/inc/qdf_types.h
@@ -690,6 +690,33 @@ struct qdf_tso_seg_t {
 	struct qdf_tso_frag_t tso_frags[FRAG_NUM_MAX];
 };
 
+/**
+ * TSO seg elem action caller locations: goes into dbg.history below.
+ * Needed to be defined outside of the feature so that
+ * callers can be coded without ifdefs (even if they get
+ * resolved to nothing)
+ */
+enum tsoseg_dbg_caller_e {
+	TSOSEG_LOC_UNDEFINED,
+	TSOSEG_LOC_INIT1,
+	TSOSEG_LOC_INIT2,
+	TSOSEG_LOC_DEINIT,
+	TSOSEG_LOC_PREPARETSO,
+	TSOSEG_LOC_TXPREPLLFAST,
+	TSOSEG_LOC_UNMAPTSO,
+	TSOSEG_LOC_ALLOC,
+	TSOSEG_LOC_FREE,
+};
+#ifdef TSOSEG_DEBUG
+
+#define MAX_TSO_SEG_ACT_HISTORY 16
+struct qdf_tso_seg_dbg_t {
+	void    *txdesc;  /* owner - (ol_txrx_tx_desc_t *) */
+	int      cur;     /* index of last valid entry */
+	uint16_t history[MAX_TSO_SEG_ACT_HISTORY];
+};
+#endif /* TSOSEG_DEBUG */
+
 /**
  * qdf_tso_seg_elem_t - tso segment element
  * @seg: instance of segment
@@ -700,6 +727,9 @@ struct qdf_tso_seg_elem_t {
 	uint16_t cookie:15,
 		on_freelist:1;
 	struct qdf_tso_seg_elem_t *next;
+#ifdef TSOSEG_DEBUG
+	struct qdf_tso_seg_dbg_t dbg;
+#endif /* TSOSEG_DEBUG */
 };
 
 /**
diff --git a/qdf/linux/src/qdf_nbuf.c b/qdf/linux/src/qdf_nbuf.c
index 9ed11cbc4d..0a16028072 100644
--- a/qdf/linux/src/qdf_nbuf.c
+++ b/qdf/linux/src/qdf_nbuf.c
@@ -1982,6 +1982,7 @@ void __qdf_nbuf_unmap_tso_segment(qdf_device_t osdev,
 			qdf_assert(0);
 			return;
 		}
+		qdf_tso_seg_dbg_record(tso_seg, TSOSEG_LOC_UNMAPTSO);
 		dma_unmap_single(osdev->dev,
 				 tso_seg->seg.tso_frags[num_frags].paddr,
 				 tso_seg->seg.tso_frags[num_frags].length,