wil6210: add scatter-gather support

When setting fragmented skb for Tx, assign skb to the last descriptor
and set number of fragments in the 1-st one
On Tx complete, HW sets "DU" bit in Tx descriptor only for the last
descriptor; so search for it using number of fragments field.
Middle descriptors may have "DU" bit not set by the hardware.

Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 41 insertions, 20 deletions

diff --git a/drivers/net/wireless/ath/wil6210/debugfs.c b/drivers/net/wireless/ath/wil6210/debugfs.c
index ea868bea9e2e..ecdabe4adec3 100644
--- a/drivers/net/wireless/ath/wil6210/debugfs.c
+++ b/drivers/net/wireless/ath/wil6210/debugfs.c
@@ -398,6 +398,44 @@ static const struct file_operations fops_reset = {
 	.open  = simple_open,
 };
 
+static void wil_seq_hexdump(struct seq_file *s, void *p, int len,
+			    const char *prefix)
+{
+	char printbuf[16 * 3 + 2];
+	int i = 0;
+	while (i < len) {
+		int l = min(len - i, 16);
+		hex_dump_to_buffer(p + i, l, 16, 1, printbuf,
+				   sizeof(printbuf), false);
+		seq_printf(s, "%s%s\n", prefix, printbuf);
+		i += l;
+	}
+}
+
+static void wil_seq_print_skb(struct seq_file *s, struct sk_buff *skb)
+{
+	int i = 0;
+	int len = skb_headlen(skb);
+	void *p = skb->data;
+	int nr_frags = skb_shinfo(skb)->nr_frags;
+
+	seq_printf(s, "    len = %d\n", len);
+	wil_seq_hexdump(s, p, len, "      : ");
+
+	if (nr_frags) {
+		seq_printf(s, "    nr_frags = %d\n", nr_frags);
+		for (i = 0; i < nr_frags; i++) {
+			const struct skb_frag_struct *frag =
+					&skb_shinfo(skb)->frags[i];
+
+			len = skb_frag_size(frag);
+			p = skb_frag_address_safe(frag);
+			seq_printf(s, "    [%2d] : len = %d\n", i, len);
+			wil_seq_hexdump(s, p, len, "      : ");
+		}
+	}
+}
+
 /*---------Tx/Rx descriptor------------*/
 static int wil_txdesc_debugfs_show(struct seq_file *s, void *data)
 {
@@ -438,26 +476,9 @@ static int wil_txdesc_debugfs_show(struct seq_file *s, void *data)
 		seq_printf(s, "  SKB = %p\n", skb);
 
 		if (skb) {
-			char printbuf[16 * 3 + 2];
-			int i = 0;
-			int len = le16_to_cpu(d->dma.length);
-			void *p = skb->data;
-
-			if (len != skb_headlen(skb)) {
-				seq_printf(s, "!!! len: desc = %d skb = %d\n",
-					   len, skb_headlen(skb));
-				len = min_t(int, len, skb_headlen(skb));
-			}
-
-			seq_printf(s, "    len = %d\n", len);
-
-			while (i < len) {
-				int l = min(len - i, 16);
-				hex_dump_to_buffer(p + i, l, 16, 1, printbuf,
-						   sizeof(printbuf), false);
-				seq_printf(s, "      : %s\n", printbuf);
-				i += l;
-			}
+			skb_get(skb);
+			wil_seq_print_skb(s, skb);
+			kfree_skb(skb);
 		}
 		seq_printf(s, "}\n");
 	} else {