scsi: scsi_debug: Add new error injection type: Abort Failed

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

  +--------+------+-------------------------------------------------------+
  | 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 "3 -10 0x12" > ${error}

will make the device return FAILED when aborting inquiry command 10 times.

Signed-off-by: Wenchao Hao <haowenchao2@huawei.com>
Link: https://lore.kernel.org/r/20231010092051.608007-8-haowenchao2@huawei.com
Tested-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index d15d007..89f47de 100644 (file)
--- 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;
@@ -5512,9 +5516,39 @@ 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;
 
@@ -5523,6 +5557,12 @@ 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;
 }