[PATCH 2/6] scsi: hisi_sas: Add manual trigger for debugfs dump

John Garry
2019-02-06T10:52:35Z

From: Luo Jiaxing <luojiaxing@huawei.com>

Add an interface to manually trigger a debugfs dump.

Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
---
drivers/scsi/hisi_sas/hisi_sas_main.c | 34 +++++++++++++++++++++++++++
1 file changed, 34 insertions(+)

diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 1a3d31d4258c..35619bdad1d5 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -2977,6 +2977,36 @@ static void hisi_sas_debugfs_snapshot_regs(struct hisi_hba *hisi_hba)
hisi_hba->hw->snapshot_restore(hisi_hba);
}

+static ssize_t hisi_sas_debugfs_trigger_dump_write(struct file *file,
+ const char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct hisi_hba *hisi_hba = file->f_inode->i_private;
+ char buf[8];
+
+ /* A bit racy, but don't care too much since it's only debugfs */
+ if (hisi_hba->debugfs_snapshot)
+ return -EFAULT;
+
+ if (count > 8)
+ return -EFAULT;
+
+ if (copy_from_user(buf, user_buf, count))
+ return -EFAULT;
+
+ if (buf[0] != '1')
+ return -EFAULT;
+
+ queue_work(hisi_hba->wq, &hisi_hba->debugfs_work);
+
+ return count;
+}
+
+static const struct file_operations hisi_sas_debugfs_trigger_dump_fops = {
+ .write = &hisi_sas_debugfs_trigger_dump_write,
+ .owner = THIS_MODULE,
+};
+
void hisi_sas_debugfs_work_handler(struct work_struct *work)
{
struct hisi_hba *hisi_hba =
@@ -2999,6 +3029,10 @@ void hisi_sas_debugfs_init(struct hisi_hba *hisi_hba)

hisi_hba->debugfs_dir = debugfs_create_dir(dev_name(dev),
hisi_sas_debugfs_dir);
+ debugfs_create_file("trigger_dump", 0600,
+ hisi_hba->debugfs_dir,
+ hisi_hba,
+ &hisi_sas_debugfs_trigger_dump_fops);

/* Alloc buffer for global */
sz = hisi_hba->hw->debugfs_reg_global->count * 4;
--
2.17.1