scsi: use external buffer for command logging
Use an external buffer for __scsi_print_command() and move command
logging over to use the per-cpu logging buffer. With that we can
guarantee the command always will always be formatted in one line.
So we can even print out a variable length command correctly across
several lines. Finally rename __scsi_print_command() to
__scsi_format_comment() to better reflect the functionality.
Tested-by: Robert Elliott <elliott@hp.com>
Reviewed-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
diff --git a/drivers/scsi/scsi_logging.c b/drivers/scsi/scsi_logging.c
index 4d20132..afba995 100644
--- a/drivers/scsi/scsi_logging.c
+++ b/drivers/scsi/scsi_logging.c
@@ -13,10 +13,10 @@
#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
-#define SCSI_LOG_BUFSIZE 128
#if (SCSI_LOG_SPOOLSIZE / SCSI_LOG_BUFSIZE) > BITS_PER_LONG
#warning SCSI logging bitmask too large
@@ -69,6 +69,24 @@
preempt_enable();
}
+static size_t scmd_format_header(char *logbuf, size_t logbuf_len,
+ struct gendisk *disk, int tag)
+{
+ size_t off = 0;
+
+ if (disk)
+ off += scnprintf(logbuf + off, logbuf_len - off,
+ "[%s] ", disk->disk_name);
+
+ if (WARN_ON(off >= logbuf_len))
+ return off;
+
+ if (tag >= 0)
+ off += scnprintf(logbuf + off, logbuf_len - off,
+ "tag#%d ", tag);
+ return off;
+}
+
int sdev_prefix_printk(const char *level, const struct scsi_device *sdev,
const char *name, const char *fmt, ...)
{
@@ -87,9 +105,11 @@
if (name)
off += scnprintf(logbuf + off, logbuf_len - off,
"[%s] ", name);
- va_start(args, fmt);
- off += vscnprintf(logbuf + off, logbuf_len - off, fmt, args);
- va_end(args);
+ if (!WARN_ON(off >= logbuf_len)) {
+ va_start(args, fmt);
+ off += vscnprintf(logbuf + off, logbuf_len - off, fmt, args);
+ va_end(args);
+ }
ret = dev_printk(level, &sdev->sdev_gendev, "%s", logbuf);
scsi_log_release_buffer(logbuf);
return ret;
@@ -111,18 +131,152 @@
logbuf = scsi_log_reserve_buffer(&logbuf_len);
if (!logbuf)
return 0;
- if (disk)
- off += scnprintf(logbuf + off, logbuf_len - off,
- "[%s] ", disk->disk_name);
-
- if (scmd->request->tag >= 0)
- off += scnprintf(logbuf + off, logbuf_len - off,
- "tag#%d ", scmd->request->tag);
- va_start(args, fmt);
- off += vscnprintf(logbuf + off, logbuf_len - off, fmt, args);
- va_end(args);
+ off = scmd_format_header(logbuf, logbuf_len, disk,
+ scmd->request->tag);
+ if (off < logbuf_len) {
+ va_start(args, fmt);
+ off += vscnprintf(logbuf + off, logbuf_len - off, fmt, args);
+ va_end(args);
+ }
ret = dev_printk(level, &scmd->device->sdev_gendev, "%s", logbuf);
scsi_log_release_buffer(logbuf);
return ret;
}
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)
+{
+ struct gendisk *disk = cmd->request->rq_disk;
+ int k;
+ char *logbuf;
+ size_t off, logbuf_len;
+
+ if (!cmd->cmnd)
+ return;
+
+ logbuf = scsi_log_reserve_buffer(&logbuf_len);
+ if (!logbuf)
+ return;
+
+ off = scmd_format_header(logbuf, logbuf_len, disk, 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, 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 = scmd_format_header(logbuf, logbuf_len, disk,
+ 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,
+ 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, logbuf);
+ scsi_log_release_buffer(logbuf);
+}
+EXPORT_SYMBOL(scsi_print_command);