Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * Hypervisor filesystem for Linux on s390 - debugfs interface
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * Copyright IBM Corp. 2010
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include "hypfs.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) static struct dentry *dbfs_dir;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) static struct hypfs_dbfs_data *hypfs_dbfs_data_alloc(struct hypfs_dbfs_file *f)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) 	struct hypfs_dbfs_data *data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) 	data = kmalloc(sizeof(*data), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) 	if (!data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) 		return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) 	data->dbfs_file = f;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) 	return data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) static void hypfs_dbfs_data_free(struct hypfs_dbfs_data *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 	data->dbfs_file->data_free(data->buf_free_ptr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 	kfree(data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) static ssize_t dbfs_read(struct file *file, char __user *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 			 size_t size, loff_t *ppos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 	struct hypfs_dbfs_data *data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 	struct hypfs_dbfs_file *df;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 	ssize_t rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 	if (*ppos != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 	df = file_inode(file)->i_private;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 	mutex_lock(&df->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	data = hypfs_dbfs_data_alloc(df);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 	if (!data) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 		mutex_unlock(&df->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 	rc = df->data_create(&data->buf, &data->buf_free_ptr, &data->size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 	if (rc) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 		mutex_unlock(&df->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 		kfree(data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 		return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 	mutex_unlock(&df->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 	rc = simple_read_from_buffer(buf, size, ppos, data->buf, data->size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 	hypfs_dbfs_data_free(data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) static long dbfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 	struct hypfs_dbfs_file *df = file_inode(file)->i_private;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 	long rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 	mutex_lock(&df->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 	if (df->unlocked_ioctl)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 		rc = df->unlocked_ioctl(file, cmd, arg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 	else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 		rc = -ENOTTY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 	mutex_unlock(&df->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 	return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) static const struct file_operations dbfs_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 	.read		= dbfs_read,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 	.llseek		= no_llseek,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 	.unlocked_ioctl = dbfs_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) void hypfs_dbfs_create_file(struct hypfs_dbfs_file *df)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 	df->dentry = debugfs_create_file(df->name, 0400, dbfs_dir, df,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 					 &dbfs_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 	mutex_init(&df->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) void hypfs_dbfs_remove_file(struct hypfs_dbfs_file *df)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 	debugfs_remove(df->dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) void hypfs_dbfs_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 	dbfs_dir = debugfs_create_dir("s390_hypfs", NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) void hypfs_dbfs_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 	debugfs_remove(dbfs_dir);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) }