[PATCH v5 07/10] scsi: scsi_debug: Add new error injection abort failed

From: Wenchao Hao
Date: Fri Sep 22 2023 - 05:30:41 EST


Add error injection type 3 to make scsi_debug_abort() return FAILED.
Fail abort command foramt:

+--------+------+-------------------------------------------------------+
| Column | Type | Description |
+--------+------+-------------------------------------------------------+
| 1 | u8 | Error type, fixed to 0x3 |
+--------+------+-------------------------------------------------------+
| 2 | s32 | Error count |
| | | 0: this rule will be ignored |
| | | positive: the rule will always take effect |
| | | negative: the rule takes effect n times where -n is |
| | | the value given. Ignored after n times |
+--------+------+-------------------------------------------------------+
| 3 | x8 | SCSI command opcode, 0xff for all commands |
+--------+------+-------------------------------------------------------+

Examples:
error=/sys/kernel/debug/scsi_debug/0:0:0:1/error
echo "0 -10 0x12" > ${error}
will make the device return FAILED when abort inquiry command 10 times.

Signed-off-by: Wenchao Hao <haowenchao2@xxxxxxxxxx>
---
drivers/scsi/scsi_debug.c | 40 +++++++++++++++++++++++++++++++++++++++
1 file changed, 40 insertions(+)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index fe1f7421f617..8a16cb9642a6 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -293,6 +293,8 @@ enum sdebug_err_type {
ERR_FAIL_CMD = 2, /* make specific scsi command's */
/* queuecmd return succeed but */
/* with errors set in scsi_cmnd */
+ ERR_ABORT_CMD_FAILED = 3, /* control return FAILED from */
+ /* scsi_debug_abort() */
};

struct sdebug_err_inject {
@@ -970,6 +972,7 @@ static int sdebug_error_show(struct seq_file *m, void *p)
list_for_each_entry_rcu(err, &devip->inject_err_list, list) {
switch (err->type) {
case ERR_TMOUT_CMD:
+ case ERR_ABORT_CMD_FAILED:
seq_printf(m, "%d\t%d\t0x%x\n", err->type, err->cnt,
err->cmd);
break;
@@ -1031,6 +1034,7 @@ static ssize_t sdebug_error_write(struct file *file, const char __user *ubuf,

switch (inject_type) {
case ERR_TMOUT_CMD:
+ case ERR_ABORT_CMD_FAILED:
if (sscanf(buf, "%d %d %hhx", &inject->type, &inject->cnt,
&inject->cmd) != 3)
goto out_error;
@@ -5504,9 +5508,39 @@ static void stop_all_queued(void)
mutex_unlock(&sdebug_host_list_mutex);
}

+static int sdebug_fail_abort(struct scsi_cmnd *cmnd)
+{
+ struct scsi_device *sdp = cmnd->device;
+ struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdp->hostdata;
+ struct sdebug_err_inject *err;
+ unsigned char *cmd = cmnd->cmnd;
+ int ret = 0;
+
+ if (devip == NULL)
+ return 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(err, &devip->inject_err_list, list) {
+ if (err->type == ERR_ABORT_CMD_FAILED &&
+ (err->cmd == cmd[0] || err->cmd == 0xff)) {
+ ret = !!err->cnt;
+ if (err->cnt < 0)
+ err->cnt++;
+
+ rcu_read_unlock();
+ return ret;
+ }
+ }
+ rcu_read_unlock();
+
+ return 0;
+}
+
static int scsi_debug_abort(struct scsi_cmnd *SCpnt)
{
bool ok = scsi_debug_abort_cmnd(SCpnt);
+ u8 *cmd = SCpnt->cmnd;
+ u8 opcode = cmd[0];

++num_aborts;

@@ -5515,6 +5549,12 @@ static int scsi_debug_abort(struct scsi_cmnd *SCpnt)
"%s: command%s found\n", __func__,
ok ? "" : " not");

+ if (sdebug_fail_abort(SCpnt)) {
+ scmd_printk(KERN_INFO, SCpnt, "fail abort command 0x%x\n",
+ opcode);
+ return FAILED;
+ }
+
return SUCCESS;
}

--
2.32.0