This adds class/raw/ support for all raw devices. It also provides a
symlink to the block device that the raw device is mapped to. For
example:
$ tree /sys/class/raw/
/sys/class/raw/
|-- raw1
| |-- dev
| `-- device -> ../../../block/sda
|-- raw2
| |-- dev
| `-- device -> ../../../block/sda/sda2
`-- rawctl
`-- dev
Note, in order to get that symlink, I had to export get_gendisk() so that
modules can use it. I hope this is ok with everyone.
This is based on a patch originally written by
Leann Ogasawara <ogasawara@osdl.org>
---
25-akpm/drivers/block/genhd.c | 2 ++
25-akpm/drivers/char/raw.c | 41 ++++++++++++++++++++++++++++++++++++++++-
2 files changed, 42 insertions(+), 1 deletion(-)
diff -puN drivers/block/genhd.c~sysfs-class-06-raw drivers/block/genhd.c
--- 25/drivers/block/genhd.c~sysfs-class-06-raw Thu Jan 15 16:39:42 2004
+++ 25-akpm/drivers/block/genhd.c Thu Jan 15 16:39:42 2004
@@ -224,6 +224,8 @@ struct gendisk *get_gendisk(dev_t dev, i
return kobj ? to_disk(kobj) : NULL;
}
+EXPORT_SYMBOL(get_gendisk);
+
#ifdef CONFIG_PROC_FS
/* iterator */
static void *part_start(struct seq_file *part, loff_t *pos)
diff -puN drivers/char/raw.c~sysfs-class-06-raw drivers/char/raw.c
--- 25/drivers/char/raw.c~sysfs-class-06-raw Thu Jan 15 16:39:42 2004
+++ 25-akpm/drivers/char/raw.c Thu Jan 15 16:39:42 2004
@@ -17,6 +17,8 @@
#include <linux/raw.h>
#include <linux/capability.h>
#include <linux/uio.h>
+#include <linux/device.h>
+#include <linux/genhd.h>
#include <asm/uaccess.h>
@@ -25,6 +27,7 @@ struct raw_device_data {
int inuse;
};
+static struct class_simple *raw_class;
static struct raw_device_data raw_devices[MAX_RAW_MINORS];
static DECLARE_MUTEX(raw_mutex);
static struct file_operations raw_ctl_fops; /* forward declaration */
@@ -122,6 +125,29 @@ raw_ioctl(struct inode *inode, struct fi
return ioctl_by_bdev(bdev, command, arg);
}
+static void bind_device(struct raw_config_request rq)
+{
+ int part;
+ struct gendisk *gen;
+ struct class_device *dev;
+ struct kobject *target = NULL;
+
+ gen = get_gendisk(MKDEV(rq.block_major, rq.block_minor), &part);
+ if (gen) {
+ if (part && gen->part[part])
+ target = &gen->part[part]->kobj;
+ else
+ target = &gen->kobj;
+ }
+
+ class_simple_device_remove(MKDEV(RAW_MAJOR, rq.raw_minor));
+ dev = class_simple_device_add(raw_class, MKDEV(RAW_MAJOR, rq.raw_minor),
+ NULL, "raw%d", rq.raw_minor);
+ if (dev && target) {
+ sysfs_create_link(&dev->kobj, target, "device");
+ }
+}
+
/*
* Deal with ioctls against the raw-device control interface, to bind
* and unbind other raw devices.
@@ -190,12 +216,15 @@ static int raw_ctl_ioctl(struct inode *i
if (rq.block_major == 0 && rq.block_minor == 0) {
/* unbind */
rawdev->binding = NULL;
+ class_simple_device_remove(MKDEV(RAW_MAJOR, rq.raw_minor));
} else {
rawdev->binding = bdget(dev);
if (rawdev->binding == NULL)
err = -ENOMEM;
- else
+ else {
__module_get(THIS_MODULE);
+ bind_device(rq);
+ }
}
up(&raw_mutex);
} else {
@@ -265,6 +294,14 @@ static int __init raw_init(void)
int i;
register_chrdev(RAW_MAJOR, "raw", &raw_fops);
+
+ raw_class = class_simple_create(THIS_MODULE, "raw");
+ if (IS_ERR(raw_class)) {
+ printk (KERN_ERR "Error creating raw class.\n");
+ return PTR_ERR(raw_class);
+ }
+ class_simple_device_add(raw_class, MKDEV(RAW_MAJOR, 0), NULL, "rawctl");
+
devfs_mk_cdev(MKDEV(RAW_MAJOR, 0),
S_IFCHR | S_IRUGO | S_IWUGO,
"raw/rawctl");
@@ -283,6 +320,8 @@ static void __exit raw_exit(void)
devfs_remove("raw/raw%d", i);
devfs_remove("raw/rawctl");
devfs_remove("raw");
+ class_simple_device_remove(MKDEV(RAW_MAJOR, 0));
+ class_simple_destroy(raw_class);
unregister_chrdev(RAW_MAJOR, "raw");
}
_