From 962d77cd4c852e6a34ffd44fc5f32ba678e02633 Mon Sep 17 00:00:00 2001 From: Wenchao Hao Date: Tue, 10 Oct 2023 17:20:44 +0800 Subject: [PATCH] scsi: scsi_debug: Define grammar to remove added error injection The grammar to remove error injection is a line with fixed 3 columns separated by spaces. First column is fixed to "-". It tells this is a removal operation. Second column is the error code to match. Third column is the scsi command to match. For example the following command would remove timeout injection of inquiry command: echo "- 0 0x12" > /sys/kernel/debug/scsi_debug/0:0:0:1/error Acked-by: Douglas Gilbert Signed-off-by: Wenchao Hao Link: https://lore.kernel.org/r/20231010092051.608007-4-haowenchao2@huawei.com Signed-off-by: Martin K. Petersen --- drivers/scsi/scsi_debug.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 46f1ee647b15f..0d5a179dbd970 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -930,6 +930,34 @@ static void sdebug_err_add(struct scsi_device *sdev, struct sdebug_err_inject *n spin_unlock(&devip->list_lock); } +static int sdebug_err_remove(struct scsi_device *sdev, const char *buf, size_t count) +{ + struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdev->hostdata; + struct sdebug_err_inject *err; + int type; + unsigned char cmd; + + if (sscanf(buf, "- %d %hhx", &type, &cmd) != 2) { + kfree(buf); + return -EINVAL; + } + + spin_lock(&devip->list_lock); + list_for_each_entry_rcu(err, &devip->inject_err_list, list) { + if (err->type == type && err->cmd == cmd) { + list_del_rcu(&err->list); + call_rcu(&err->rcu, sdebug_err_free); + spin_unlock(&devip->list_lock); + kfree(buf); + return count; + } + } + spin_unlock(&devip->list_lock); + + kfree(buf); + return -EINVAL; +} + static int sdebug_error_show(struct seq_file *m, void *p) { struct scsi_device *sdev = (struct scsi_device *)m->private; @@ -987,6 +1015,9 @@ static ssize_t sdebug_error_write(struct file *file, const char __user *ubuf, return -EFAULT; } + if (buf[0] == '-') + return sdebug_err_remove(sdev, buf, count); + if (sscanf(buf, "%d", &inject_type) != 1) { kfree(buf); return -EINVAL; -- 2.30.2