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linux/drivers/scsi/scsi_debugfs.c
Bart Van Assche ba0f09b0db scsi: core: Improve the code for showing commands in debugfs
Some but not all command information is cleared by scsi_end_request().
As an example, if scsi_show_rq() is called after a SCSI command has been
allocated and before SCMD_INITIALIZED is set, .cmnd holds the CDB
of a previous command. Showing that information in debugfs is confusing.
Hence this patch that restricts the information shown in debugfs to
valid information.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240325224755.1477910-3-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2024-04-08 22:12:33 -04:00

76 lines
2.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/bitops.h>
#include <linux/cleanup.h>
#include <linux/seq_file.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_host.h>
#include "scsi_debugfs.h"
#define SCSI_CMD_FLAG_NAME(name)[const_ilog2(SCMD_##name)] = #name
static const char *const scsi_cmd_flags[] = {
SCSI_CMD_FLAG_NAME(TAGGED),
SCSI_CMD_FLAG_NAME(INITIALIZED),
SCSI_CMD_FLAG_NAME(LAST),
};
#undef SCSI_CMD_FLAG_NAME
static int scsi_flags_show(struct seq_file *m, const unsigned long flags,
const char *const *flag_name, int flag_name_count)
{
bool sep = false;
int i;
for_each_set_bit(i, &flags, BITS_PER_LONG) {
if (sep)
seq_puts(m, "|");
sep = true;
if (i < flag_name_count && flag_name[i])
seq_puts(m, flag_name[i]);
else
seq_printf(m, "%d", i);
}
return 0;
}
static const char *scsi_cmd_list_info(struct scsi_cmnd *cmd)
{
struct Scsi_Host *shost = cmd->device->host;
struct scsi_cmnd *cmd2;
guard(spinlock_irq)(shost->host_lock);
list_for_each_entry(cmd2, &shost->eh_abort_list, eh_entry)
if (cmd == cmd2)
return "on eh_abort_list";
list_for_each_entry(cmd2, &shost->eh_cmd_q, eh_entry)
if (cmd == cmd2)
return "on eh_cmd_q";
return NULL;
}
void scsi_show_rq(struct seq_file *m, struct request *rq)
{
struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
int alloc_ms = jiffies_to_msecs(jiffies - cmd->jiffies_at_alloc);
int timeout_ms = jiffies_to_msecs(rq->timeout);
char buf[80] = "(?)";
if (cmd->flags & SCMD_INITIALIZED) {
const char *list_info = scsi_cmd_list_info(cmd);
__scsi_format_command(buf, sizeof(buf), cmd->cmnd, cmd->cmd_len);
seq_printf(m, ", .cmd=%s, .retries=%d, .allowed=%d, .result = %#x%s%s",
buf, cmd->retries, cmd->allowed, cmd->result,
list_info ? ", " : "", list_info ? : "");
seq_printf(m, ", .timeout=%d.%03d, allocated %d.%03d s ago",
timeout_ms / 1000, timeout_ms % 1000,
alloc_ms / 1000, alloc_ms % 1000);
}
seq_printf(m, ", .flags=");
scsi_flags_show(m, cmd->flags, scsi_cmd_flags,
ARRAY_SIZE(scsi_cmd_flags));
}