[SCSI] add scsi trace core functions and put trace points

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@jp.fujitsu.com>
Signed-off-by: Kei Tokunaga <tokunaga.keiich@jp.fujitsu.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/scsi/scsi_trace.c b/drivers/scsi/scsi_trace.c
new file mode 100644
index 0000000..9a3342a
--- /dev/null
+++ b/drivers/scsi/scsi_trace.c
@@ -0,0 +1,185 @@
+/*
+ * Copyright (C) 2010 FUJITSU LIMITED
+ * Copyright (C) 2010 Tomohiro Kusumi <kusumi.tomohiro@jp.fujitsu.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+#include <linux/kernel.h>
+#include <linux/trace_seq.h>
+#include <trace/events/scsi.h>
+
+#define SERVICE_ACTION(cdb) ((cdb[8] << 8) | cdb[9])
+
+static const char *
+scsi_trace_misc(struct trace_seq *, unsigned char *, int);
+
+static const char *
+scsi_trace_rw6(struct trace_seq *p, unsigned char *cdb, int len)
+{
+	const char *ret = p->buffer + p->len;
+	sector_t lba = 0, txlen = 0;
+
+	lba |= ((cdb[1] & 0x1F) << 16);
+	lba |=  (cdb[2] << 8);
+	lba |=   cdb[3];
+	txlen = cdb[4];
+
+	trace_seq_printf(p, "lba=%llu txlen=%llu",
+			 (unsigned long long)lba, (unsigned long long)txlen);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *
+scsi_trace_rw10(struct trace_seq *p, unsigned char *cdb, int len)
+{
+	const char *ret = p->buffer + p->len;
+	sector_t lba = 0, txlen = 0;
+
+	lba |= (cdb[2] << 24);
+	lba |= (cdb[3] << 16);
+	lba |= (cdb[4] << 8);
+	lba |=  cdb[5];
+	txlen |= (cdb[7] << 8);
+	txlen |=  cdb[8];
+
+	trace_seq_printf(p, "lba=%llu txlen=%llu",
+			 (unsigned long long)lba, (unsigned long long)txlen);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *
+scsi_trace_rw12(struct trace_seq *p, unsigned char *cdb, int len)
+{
+	const char *ret = p->buffer + p->len;
+	sector_t lba = 0, txlen = 0;
+
+	lba |= (cdb[2] << 24);
+	lba |= (cdb[3] << 16);
+	lba |= (cdb[4] << 8);
+	lba |=  cdb[5];
+	txlen |= (cdb[6] << 24);
+	txlen |= (cdb[7] << 16);
+	txlen |= (cdb[8] << 8);
+	txlen |=  cdb[9];
+
+	trace_seq_printf(p, "lba=%llu txlen=%llu",
+			 (unsigned long long)lba, (unsigned long long)txlen);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *
+scsi_trace_rw16(struct trace_seq *p, unsigned char *cdb, int len)
+{
+	const char *ret = p->buffer + p->len;
+	sector_t lba = 0, txlen = 0;
+
+	lba |= ((u64)cdb[2] << 56);
+	lba |= ((u64)cdb[3] << 48);
+	lba |= ((u64)cdb[4] << 40);
+	lba |= ((u64)cdb[5] << 32);
+	lba |= (cdb[6] << 24);
+	lba |= (cdb[7] << 16);
+	lba |= (cdb[8] << 8);
+	lba |=  cdb[9];
+	txlen |= (cdb[10] << 24);
+	txlen |= (cdb[11] << 16);
+	txlen |= (cdb[12] << 8);
+	txlen |=  cdb[13];
+
+	trace_seq_printf(p, "lba=%llu txlen=%llu",
+			 (unsigned long long)lba, (unsigned long long)txlen);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *
+scsi_trace_rw32(struct trace_seq *p, unsigned char *cdb, int len)
+{
+	const char *ret = p->buffer + p->len;
+	sector_t lba = 0, txlen = 0;
+
+	lba |= ((u64)cdb[12] << 56);
+	lba |= ((u64)cdb[13] << 48);
+	lba |= ((u64)cdb[14] << 40);
+	lba |= ((u64)cdb[15] << 32);
+	lba |= (cdb[16] << 24);
+	lba |= (cdb[17] << 16);
+	lba |= (cdb[18] << 8);
+	lba |=  cdb[19];
+	txlen |= (cdb[28] << 24);
+	txlen |= (cdb[29] << 16);
+	txlen |= (cdb[30] << 8);
+	txlen |=  cdb[31];
+
+	trace_seq_printf(p, "%s_32 lba=%llu txlen=%llu",
+			(SERVICE_ACTION(cdb) == READ_32 ? "READ" : "WRITE"),
+			(unsigned long long)lba, (unsigned long long)txlen);
+
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *
+scsi_trace_varlen(struct trace_seq *p, unsigned char *cdb, int len)
+{
+	switch (SERVICE_ACTION(cdb)) {
+	case READ_32:
+	case WRITE_32:
+		return scsi_trace_rw32(p, cdb, len);
+	default:
+		return scsi_trace_misc(p, cdb, len);
+	}
+}
+
+static const char *
+scsi_trace_misc(struct trace_seq *p, unsigned char *cdb, int len)
+{
+	const char *ret = p->buffer + p->len;
+
+	trace_seq_printf(p, "-");
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+const char *
+scsi_trace_parse_cdb(struct trace_seq *p, unsigned char *cdb, int len)
+{
+	switch (cdb[0]) {
+	case READ_6:
+	case WRITE_6:
+		return scsi_trace_rw6(p, cdb, len);
+	case READ_10:
+	case WRITE_10:
+		return scsi_trace_rw10(p, cdb, len);
+	case READ_12:
+	case WRITE_12:
+		return scsi_trace_rw12(p, cdb, len);
+	case READ_16:
+	case WRITE_16:
+		return scsi_trace_rw16(p, cdb, len);
+	case VARIABLE_LENGTH_CMD:
+		return scsi_trace_varlen(p, cdb, len);
+	default:
+		return scsi_trace_misc(p, cdb, len);
+	}
+}