v4.19.13 snapshot.
diff --git a/drivers/scsi/scsi_logging.c b/drivers/scsi/scsi_logging.c
new file mode 100644
index 0000000..bd70339
--- /dev/null
+++ b/drivers/scsi/scsi_logging.c
@@ -0,0 +1,485 @@
+/*
+ * scsi_logging.c
+ *
+ * Copyright (C) 2014 SUSE Linux Products GmbH
+ * Copyright (C) 2014 Hannes Reinecke <hare@suse.de>
+ *
+ * This file is released under the GPLv2
+ */
+
+#include <linux/kernel.h>
+#include <linux/atomic.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_dbg.h>
+
+#define SCSI_LOG_SPOOLSIZE 4096
+
+#if (SCSI_LOG_SPOOLSIZE / SCSI_LOG_BUFSIZE) > BITS_PER_LONG
+#warning SCSI logging bitmask too large
+#endif
+
+struct scsi_log_buf {
+	char buffer[SCSI_LOG_SPOOLSIZE];
+	unsigned long map;
+};
+
+static DEFINE_PER_CPU(struct scsi_log_buf, scsi_format_log);
+
+static char *scsi_log_reserve_buffer(size_t *len)
+{
+	struct scsi_log_buf *buf;
+	unsigned long map_bits = sizeof(buf->buffer) / SCSI_LOG_BUFSIZE;
+	unsigned long idx = 0;
+
+	preempt_disable();
+	buf = this_cpu_ptr(&scsi_format_log);
+	idx = find_first_zero_bit(&buf->map, map_bits);
+	if (likely(idx < map_bits)) {
+		while (test_and_set_bit(idx, &buf->map)) {
+			idx = find_next_zero_bit(&buf->map, map_bits, idx);
+			if (idx >= map_bits)
+				break;
+		}
+	}
+	if (WARN_ON(idx >= map_bits)) {
+		preempt_enable();
+		return NULL;
+	}
+	*len = SCSI_LOG_BUFSIZE;
+	return buf->buffer + idx * SCSI_LOG_BUFSIZE;
+}
+
+static void scsi_log_release_buffer(char *bufptr)
+{
+	struct scsi_log_buf *buf;
+	unsigned long idx;
+	int ret;
+
+	buf = this_cpu_ptr(&scsi_format_log);
+	if (bufptr >= buf->buffer &&
+	    bufptr < buf->buffer + SCSI_LOG_SPOOLSIZE) {
+		idx = (bufptr - buf->buffer) / SCSI_LOG_BUFSIZE;
+		ret = test_and_clear_bit(idx, &buf->map);
+		WARN_ON(!ret);
+	}
+	preempt_enable();
+}
+
+static inline const char *scmd_name(const struct scsi_cmnd *scmd)
+{
+	return scmd->request->rq_disk ?
+		scmd->request->rq_disk->disk_name : NULL;
+}
+
+static size_t sdev_format_header(char *logbuf, size_t logbuf_len,
+				 const char *name, int tag)
+{
+	size_t off = 0;
+
+	if (name)
+		off += scnprintf(logbuf + off, logbuf_len - off,
+				 "[%s] ", name);
+
+	if (WARN_ON(off >= logbuf_len))
+		return off;
+
+	if (tag >= 0)
+		off += scnprintf(logbuf + off, logbuf_len - off,
+				 "tag#%d ", tag);
+	return off;
+}
+
+void sdev_prefix_printk(const char *level, const struct scsi_device *sdev,
+			const char *name, const char *fmt, ...)
+{
+	va_list args;
+	char *logbuf;
+	size_t off = 0, logbuf_len;
+
+	if (!sdev)
+		return;
+
+	logbuf = scsi_log_reserve_buffer(&logbuf_len);
+	if (!logbuf)
+		return;
+
+	if (name)
+		off += scnprintf(logbuf + off, logbuf_len - off,
+				 "[%s] ", name);
+	if (!WARN_ON(off >= logbuf_len)) {
+		va_start(args, fmt);
+		off += vscnprintf(logbuf + off, logbuf_len - off, fmt, args);
+		va_end(args);
+	}
+	dev_printk(level, &sdev->sdev_gendev, "%s", logbuf);
+	scsi_log_release_buffer(logbuf);
+}
+EXPORT_SYMBOL(sdev_prefix_printk);
+
+void scmd_printk(const char *level, const struct scsi_cmnd *scmd,
+		const char *fmt, ...)
+{
+	va_list args;
+	char *logbuf;
+	size_t off = 0, logbuf_len;
+
+	if (!scmd || !scmd->cmnd)
+		return;
+
+	logbuf = scsi_log_reserve_buffer(&logbuf_len);
+	if (!logbuf)
+		return;
+	off = sdev_format_header(logbuf, logbuf_len, scmd_name(scmd),
+				 scmd->request->tag);
+	if (off < logbuf_len) {
+		va_start(args, fmt);
+		off += vscnprintf(logbuf + off, logbuf_len - off, fmt, args);
+		va_end(args);
+	}
+	dev_printk(level, &scmd->device->sdev_gendev, "%s", logbuf);
+	scsi_log_release_buffer(logbuf);
+}
+EXPORT_SYMBOL(scmd_printk);
+
+static size_t scsi_format_opcode_name(char *buffer, size_t buf_len,
+				      const unsigned char *cdbp)
+{
+	int sa, cdb0;
+	const char *cdb_name = NULL, *sa_name = NULL;
+	size_t off;
+
+	cdb0 = cdbp[0];
+	if (cdb0 == VARIABLE_LENGTH_CMD) {
+		int len = scsi_varlen_cdb_length(cdbp);
+
+		if (len < 10) {
+			off = scnprintf(buffer, buf_len,
+					"short variable length command, len=%d",
+					len);
+			return off;
+		}
+		sa = (cdbp[8] << 8) + cdbp[9];
+	} else
+		sa = cdbp[1] & 0x1f;
+
+	if (!scsi_opcode_sa_name(cdb0, sa, &cdb_name, &sa_name)) {
+		if (cdb_name)
+			off = scnprintf(buffer, buf_len, "%s", cdb_name);
+		else {
+			off = scnprintf(buffer, buf_len, "opcode=0x%x", cdb0);
+			if (WARN_ON(off >= buf_len))
+				return off;
+			if (cdb0 >= VENDOR_SPECIFIC_CDB)
+				off += scnprintf(buffer + off, buf_len - off,
+						 " (vendor)");
+			else if (cdb0 >= 0x60 && cdb0 < 0x7e)
+				off += scnprintf(buffer + off, buf_len - off,
+						 " (reserved)");
+		}
+	} else {
+		if (sa_name)
+			off = scnprintf(buffer, buf_len, "%s", sa_name);
+		else if (cdb_name)
+			off = scnprintf(buffer, buf_len, "%s, sa=0x%x",
+					cdb_name, sa);
+		else
+			off = scnprintf(buffer, buf_len,
+					"opcode=0x%x, sa=0x%x", cdb0, sa);
+	}
+	WARN_ON(off >= buf_len);
+	return off;
+}
+
+size_t __scsi_format_command(char *logbuf, size_t logbuf_len,
+			     const unsigned char *cdb, size_t cdb_len)
+{
+	int len, k;
+	size_t off;
+
+	off = scsi_format_opcode_name(logbuf, logbuf_len, cdb);
+	if (off >= logbuf_len)
+		return off;
+	len = scsi_command_size(cdb);
+	if (cdb_len < len)
+		len = cdb_len;
+	/* print out all bytes in cdb */
+	for (k = 0; k < len; ++k) {
+		if (off > logbuf_len - 3)
+			break;
+		off += scnprintf(logbuf + off, logbuf_len - off,
+				 " %02x", cdb[k]);
+	}
+	return off;
+}
+EXPORT_SYMBOL(__scsi_format_command);
+
+void scsi_print_command(struct scsi_cmnd *cmd)
+{
+	int k;
+	char *logbuf;
+	size_t off, logbuf_len;
+
+	if (!cmd->cmnd)
+		return;
+
+	logbuf = scsi_log_reserve_buffer(&logbuf_len);
+	if (!logbuf)
+		return;
+
+	off = sdev_format_header(logbuf, logbuf_len,
+				 scmd_name(cmd), cmd->request->tag);
+	if (off >= logbuf_len)
+		goto out_printk;
+	off += scnprintf(logbuf + off, logbuf_len - off, "CDB: ");
+	if (WARN_ON(off >= logbuf_len))
+		goto out_printk;
+
+	off += scsi_format_opcode_name(logbuf + off, logbuf_len - off,
+				       cmd->cmnd);
+	if (off >= logbuf_len)
+		goto out_printk;
+
+	/* print out all bytes in cdb */
+	if (cmd->cmd_len > 16) {
+		/* Print opcode in one line and use separate lines for CDB */
+		off += scnprintf(logbuf + off, logbuf_len - off, "\n");
+		dev_printk(KERN_INFO, &cmd->device->sdev_gendev, "%s", logbuf);
+		scsi_log_release_buffer(logbuf);
+		for (k = 0; k < cmd->cmd_len; k += 16) {
+			size_t linelen = min(cmd->cmd_len - k, 16);
+
+			logbuf = scsi_log_reserve_buffer(&logbuf_len);
+			if (!logbuf)
+				break;
+			off = sdev_format_header(logbuf, logbuf_len,
+						 scmd_name(cmd),
+						 cmd->request->tag);
+			if (!WARN_ON(off > logbuf_len - 58)) {
+				off += scnprintf(logbuf + off, logbuf_len - off,
+						 "CDB[%02x]: ", k);
+				hex_dump_to_buffer(&cmd->cmnd[k], linelen,
+						   16, 1, logbuf + off,
+						   logbuf_len - off, false);
+			}
+			dev_printk(KERN_INFO, &cmd->device->sdev_gendev, "%s",
+				   logbuf);
+			scsi_log_release_buffer(logbuf);
+		}
+		return;
+	}
+	if (!WARN_ON(off > logbuf_len - 49)) {
+		off += scnprintf(logbuf + off, logbuf_len - off, " ");
+		hex_dump_to_buffer(cmd->cmnd, cmd->cmd_len, 16, 1,
+				   logbuf + off, logbuf_len - off,
+				   false);
+	}
+out_printk:
+	dev_printk(KERN_INFO, &cmd->device->sdev_gendev, "%s", logbuf);
+	scsi_log_release_buffer(logbuf);
+}
+EXPORT_SYMBOL(scsi_print_command);
+
+static size_t
+scsi_format_extd_sense(char *buffer, size_t buf_len,
+		       unsigned char asc, unsigned char ascq)
+{
+	size_t off = 0;
+	const char *extd_sense_fmt = NULL;
+	const char *extd_sense_str = scsi_extd_sense_format(asc, ascq,
+							    &extd_sense_fmt);
+
+	if (extd_sense_str) {
+		off = scnprintf(buffer, buf_len, "Add. Sense: %s",
+				extd_sense_str);
+		if (extd_sense_fmt)
+			off += scnprintf(buffer + off, buf_len - off,
+					 "(%s%x)", extd_sense_fmt, ascq);
+	} else {
+		if (asc >= 0x80)
+			off = scnprintf(buffer, buf_len, "<<vendor>>");
+		off += scnprintf(buffer + off, buf_len - off,
+				 "ASC=0x%x ", asc);
+		if (ascq >= 0x80)
+			off += scnprintf(buffer + off, buf_len - off,
+					 "<<vendor>>");
+		off += scnprintf(buffer + off, buf_len - off,
+				 "ASCQ=0x%x ", ascq);
+	}
+	return off;
+}
+
+static size_t
+scsi_format_sense_hdr(char *buffer, size_t buf_len,
+		      const struct scsi_sense_hdr *sshdr)
+{
+	const char *sense_txt;
+	size_t off;
+
+	off = scnprintf(buffer, buf_len, "Sense Key : ");
+	sense_txt = scsi_sense_key_string(sshdr->sense_key);
+	if (sense_txt)
+		off += scnprintf(buffer + off, buf_len - off,
+				 "%s ", sense_txt);
+	else
+		off += scnprintf(buffer + off, buf_len - off,
+				 "0x%x ", sshdr->sense_key);
+	off += scnprintf(buffer + off, buf_len - off,
+		scsi_sense_is_deferred(sshdr) ? "[deferred] " : "[current] ");
+
+	if (sshdr->response_code >= 0x72)
+		off += scnprintf(buffer + off, buf_len - off, "[descriptor] ");
+	return off;
+}
+
+static void
+scsi_log_dump_sense(const struct scsi_device *sdev, const char *name, int tag,
+		    const unsigned char *sense_buffer, int sense_len)
+{
+	char *logbuf;
+	size_t logbuf_len;
+	int i;
+
+	logbuf = scsi_log_reserve_buffer(&logbuf_len);
+	if (!logbuf)
+		return;
+
+	for (i = 0; i < sense_len; i += 16) {
+		int len = min(sense_len - i, 16);
+		size_t off;
+
+		off = sdev_format_header(logbuf, logbuf_len,
+					 name, tag);
+		hex_dump_to_buffer(&sense_buffer[i], len, 16, 1,
+				   logbuf + off, logbuf_len - off,
+				   false);
+		dev_printk(KERN_INFO, &sdev->sdev_gendev, "%s", logbuf);
+	}
+	scsi_log_release_buffer(logbuf);
+}
+
+static void
+scsi_log_print_sense_hdr(const struct scsi_device *sdev, const char *name,
+			 int tag, const struct scsi_sense_hdr *sshdr)
+{
+	char *logbuf;
+	size_t off, logbuf_len;
+
+	logbuf = scsi_log_reserve_buffer(&logbuf_len);
+	if (!logbuf)
+		return;
+	off = sdev_format_header(logbuf, logbuf_len, name, tag);
+	off += scsi_format_sense_hdr(logbuf + off, logbuf_len - off, sshdr);
+	dev_printk(KERN_INFO, &sdev->sdev_gendev, "%s", logbuf);
+	scsi_log_release_buffer(logbuf);
+
+	logbuf = scsi_log_reserve_buffer(&logbuf_len);
+	if (!logbuf)
+		return;
+	off = sdev_format_header(logbuf, logbuf_len, name, tag);
+	off += scsi_format_extd_sense(logbuf + off, logbuf_len - off,
+				      sshdr->asc, sshdr->ascq);
+	dev_printk(KERN_INFO, &sdev->sdev_gendev, "%s", logbuf);
+	scsi_log_release_buffer(logbuf);
+}
+
+static void
+scsi_log_print_sense(const struct scsi_device *sdev, const char *name, int tag,
+		     const unsigned char *sense_buffer, int sense_len)
+{
+	struct scsi_sense_hdr sshdr;
+
+	if (scsi_normalize_sense(sense_buffer, sense_len, &sshdr))
+		scsi_log_print_sense_hdr(sdev, name, tag, &sshdr);
+	else
+		scsi_log_dump_sense(sdev, name, tag, sense_buffer, sense_len);
+}
+
+/*
+ * Print normalized SCSI sense header with a prefix.
+ */
+void
+scsi_print_sense_hdr(const struct scsi_device *sdev, const char *name,
+		     const struct scsi_sense_hdr *sshdr)
+{
+	scsi_log_print_sense_hdr(sdev, name, -1, sshdr);
+}
+EXPORT_SYMBOL(scsi_print_sense_hdr);
+
+/* Normalize and print sense buffer with name prefix */
+void __scsi_print_sense(const struct scsi_device *sdev, const char *name,
+			const unsigned char *sense_buffer, int sense_len)
+{
+	scsi_log_print_sense(sdev, name, -1, sense_buffer, sense_len);
+}
+EXPORT_SYMBOL(__scsi_print_sense);
+
+/* Normalize and print sense buffer in SCSI command */
+void scsi_print_sense(const struct scsi_cmnd *cmd)
+{
+	scsi_log_print_sense(cmd->device, scmd_name(cmd), cmd->request->tag,
+			     cmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
+}
+EXPORT_SYMBOL(scsi_print_sense);
+
+void scsi_print_result(const struct scsi_cmnd *cmd, const char *msg,
+		       int disposition)
+{
+	char *logbuf;
+	size_t off, logbuf_len;
+	const char *mlret_string = scsi_mlreturn_string(disposition);
+	const char *hb_string = scsi_hostbyte_string(cmd->result);
+	const char *db_string = scsi_driverbyte_string(cmd->result);
+
+	logbuf = scsi_log_reserve_buffer(&logbuf_len);
+	if (!logbuf)
+		return;
+
+	off = sdev_format_header(logbuf, logbuf_len,
+				 scmd_name(cmd), cmd->request->tag);
+
+	if (off >= logbuf_len)
+		goto out_printk;
+
+	if (msg) {
+		off += scnprintf(logbuf + off, logbuf_len - off,
+				 "%s: ", msg);
+		if (WARN_ON(off >= logbuf_len))
+			goto out_printk;
+	}
+	if (mlret_string)
+		off += scnprintf(logbuf + off, logbuf_len - off,
+				 "%s ", mlret_string);
+	else
+		off += scnprintf(logbuf + off, logbuf_len - off,
+				 "UNKNOWN(0x%02x) ", disposition);
+	if (WARN_ON(off >= logbuf_len))
+		goto out_printk;
+
+	off += scnprintf(logbuf + off, logbuf_len - off, "Result: ");
+	if (WARN_ON(off >= logbuf_len))
+		goto out_printk;
+
+	if (hb_string)
+		off += scnprintf(logbuf + off, logbuf_len - off,
+				 "hostbyte=%s ", hb_string);
+	else
+		off += scnprintf(logbuf + off, logbuf_len - off,
+				 "hostbyte=0x%02x ", host_byte(cmd->result));
+	if (WARN_ON(off >= logbuf_len))
+		goto out_printk;
+
+	if (db_string)
+		off += scnprintf(logbuf + off, logbuf_len - off,
+				 "driverbyte=%s", db_string);
+	else
+		off += scnprintf(logbuf + off, logbuf_len - off,
+				 "driverbyte=0x%02x", driver_byte(cmd->result));
+out_printk:
+	dev_printk(KERN_INFO, &cmd->device->sdev_gendev, "%s", logbuf);
+	scsi_log_release_buffer(logbuf);
+}
+EXPORT_SYMBOL(scsi_print_result);