hcl.c

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/* $Id$
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 *  hcl - SGI's Hardware Graph compatibility layer.
 *
 * Copyright (C) 1992 - 1997, 2000 Silicon Graphics, Inc.
 * Copyright (C) 2000 by Colin Ngam
 */

#include <linux/types.h>
#include <linux/config.h>
#include <linux/slab.h>
#include <linux/ctype.h>
#include <linux/module.h>
#include <linux/init.h>
#include <asm/sn/sgi.h>
#include <linux/devfs_fs.h>
#include <linux/devfs_fs_kernel.h>
#include <asm/io.h>
#include <asm/sn/iograph.h>
#include <asm/sn/invent.h>
#include <asm/sn/hcl.h>
#include <asm/sn/labelcl.h>

#define HCL_NAME "SGI-HWGRAPH COMPATIBILITY DRIVER"
#define HCL_TEMP_NAME "HCL_TEMP_NAME_USED_FOR_HWGRAPH_VERTEX_CREATE"
#define HCL_TEMP_NAME_LEN 44 
#define HCL_VERSION "1.0"
devfs_handle_t hwgraph_root = NULL;

/*
 * Debug flag definition.
 */
#define OPTION_NONE             0x00
#define HCL_DEBUG_NONE 0x00000
#define HCL_DEBUG_ALL  0x0ffff
#if defined(CONFIG_HCL_DEBUG)
static unsigned int hcl_debug_init __initdata = HCL_DEBUG_NONE;
#endif
static unsigned int hcl_debug = HCL_DEBUG_NONE;
static unsigned int boot_options = OPTION_NONE;

/*
 * Some Global definitions.
 */
spinlock_t hcl_spinlock;
devfs_handle_t hcl_handle = NULL;

/*
 * HCL device driver.
 * The purpose of this device driver is to provide a facility 
 * for User Level Apps e.g. hinv, ioconfig etc. an ioctl path 
 * to manipulate label entries without having to implement
 * system call interfaces.  This methodology will enable us to 
 * make this feature module loadable.
 */
static int hcl_open(struct inode * inode, struct file * filp)
{
	if (hcl_debug) {
        	printk("HCL: hcl_open called.\n");
	}

        return(0);

}

static int hcl_close(struct inode * inode, struct file * filp)
{

	if (hcl_debug) {
        	printk("HCL: hcl_close called.\n");
	}

        return(0);

}

static int hcl_ioctl(struct inode * inode, struct file * file,
        unsigned int cmd, unsigned long arg)
{

	if (hcl_debug) {
		printk("HCL: hcl_ioctl called.\n");
	}

	switch (cmd) {
		default:
			if (hcl_debug) {
				printk("HCL: hcl_ioctl cmd = 0x%x\n", cmd);
			}
	}

	return(0);

}

struct file_operations hcl_fops = {
	NULL,		/* lseek - default */
	NULL,		/* read - general block-dev read */
	NULL,		/* write - general block-dev write */
	NULL,		/* readdir - bad */
	NULL,		/* poll */
	hcl_ioctl,      /* ioctl */
	NULL,		/* mmap */
	hcl_open,	/* open */
	NULL,		/* flush */
	hcl_close,	/* release */
	NULL,		/* fsync */
	NULL,		/* fasync */
	NULL,		/* check_media_change */
	NULL,		/* revalidate */
	NULL		/* lock */
};


/*
 * init_hcl() - Boot time initialization.  Ensure that it is called 
 *	after devfs has been initialized.
 *
 * For now this routine is being called out of devfs/base.c.  Actually 
 * Not a bad place to be ..
 *
 */
#ifdef MODULE
int init_module (void)
#else
int __init init_hcl(void)
#endif
{
	extern void string_table_init(struct string_table *);
	extern struct string_table label_string_table;
	int rv = 0;

	printk ("\n%s: v%s Colin Ngam ([e-mail])\n",
		HCL_NAME, HCL_VERSION);
#if defined(CONFIG_HCL_DEBUG) && !defined(MODULE)
	hcl_debug = hcl_debug_init;
	printk ("%s: hcl_debug: 0x%0x\n", HCL_NAME, hcl_debug);
#endif
	printk ("\n%s: boot_options: 0x%0x\n", HCL_NAME, boot_options);
	spin_lock_init(&hcl_spinlock);

	/*
	 * Create the hwgraph_root on devfs.
	 */
	rv = hwgraph_path_add(NULL, "hw", &hwgraph_root);
	if (rv)
		printk ("init_hcl: Failed to create hwgraph_root. Error = %d.\n", rv);

	/*
	 * Create the hcl driver to support inventory entry manipulations.
	 * By default, it is expected that devfs is mounted on /dev.
	 *
	 */
	hcl_handle = hwgraph_register(hwgraph_root, ".hcl",
			0, DEVFS_FL_AUTO_DEVNUM,
			0, 0,
			S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP, 0, 0,
			&hcl_fops, NULL);

	if (hcl_handle == NULL) {
		panic("HCL: Unable to create HCL Driver in init_hcl().\n");
		return(0);
	}

	/*
	 * Initialize the HCL string table.
	 */
	string_table_init(&label_string_table);

	return(0);

}


/*
 * hcl_setup() - Process boot time parameters if given.
 *	"hcl="
 *	This routine gets called only if "hcl=" is given in the 
 *	boot line and before init_hcl().
 *
 *	We currently do not have any boot options .. when we do, 
 *	functionalities can be added here.
 *
 */
static int __init hcl_setup(char *str)
{
    while ( (*str != '\0') && !isspace (*str) )
    {
	printk("HCL: Boot time parameter %s\n", str);
#ifdef CONFIG_HCL_DEBUG
        if (strncmp (str, "all", 3) == 0) {
            hcl_debug_init |= HCL_DEBUG_ALL;
            str += 3;
        } else 
        	return 0;
#endif
        if (*str != ',') return 0;
        ++str;
    }

    return 1;

}

__setup("hcl=", hcl_setup);


/*
 * Set device specific "fast information".
 *
 */
void
hwgraph_fastinfo_set(devfs_handle_t de, arbitrary_info_t fastinfo)
{

	if (hcl_debug) {
		printk("HCL: hwgraph_fastinfo_set handle 0x%p fastinfo %ld\n",
			de, fastinfo);
	}
		
	labelcl_info_replace_IDX(de, HWGRAPH_FASTINFO, fastinfo, NULL);

}


/*
 * Get device specific "fast information".
 *
 */
arbitrary_info_t
hwgraph_fastinfo_get(devfs_handle_t de)
{
	arbitrary_info_t fastinfo;
	int rv;

	if (!de) {
		printk(KERN_WARNING "HCL: hwgraph_fastinfo_get handle given is NULL.\n");
		return(-1);
	}

	rv = labelcl_info_get_IDX(de, HWGRAPH_FASTINFO, &fastinfo);
	if (rv == 0)
		return(fastinfo);

	return(0);
}


/*
 * hwgraph_connectpt_set - Sets the connect point handle in de to the 
 *	given connect_de handle.  By default, the connect point of the 
 *	devfs node is the parent.  This effectively changes this assumption.
 */
int
hwgraph_connectpt_set(devfs_handle_t de, devfs_handle_t connect_de)
{
	int rv;

	if (!de)
		return(-1);

	rv = labelcl_info_connectpt_set(de, connect_de);

	return(rv);
}


/*
 * hwgraph_connectpt_get: Returns the entry's connect point  in the devfs 
 *	tree.
 */
devfs_handle_t
hwgraph_connectpt_get(devfs_handle_t de)
{
	int rv;
	arbitrary_info_t info;
	devfs_handle_t connect;

	rv = labelcl_info_get_IDX(de, HWGRAPH_CONNECTPT, &info);
	if (rv != 0) {
		return(NULL);
	}

	connect = (devfs_handle_t)info;
	return(connect);

}


/*
 * hwgraph_mk_dir - Creates a directory entry with devfs.
 *	Note that a directory entry in devfs can have children 
 *	but it cannot be a char|block special file.
 */
devfs_handle_t
hwgraph_mk_dir(devfs_handle_t de, const char *name,
                unsigned int namelen, void *info)
{

	int rv;
	labelcl_info_t *labelcl_info = NULL;
	devfs_handle_t new_devfs_handle = NULL;
	devfs_handle_t parent = NULL;

	/*
	 * Create the device info structure for hwgraph compatiblity support.
	 */
	labelcl_info = labelcl_info_create();
	if (!labelcl_info)
		return(NULL);

	/*
	 * Create a devfs entry.
	 */
	new_devfs_handle = devfs_mk_dir(de, name, (void *)labelcl_info);
	if (!new_devfs_handle) {
		labelcl_info_destroy(labelcl_info);
		return(NULL);
	}

	/*
	 * Get the parent handle.
	 */
	parent = devfs_get_parent (new_devfs_handle);

	/*
	 * To provide the same semantics as the hwgraph, set the connect point.
	 */
	rv = hwgraph_connectpt_set(new_devfs_handle, parent);
	if (!rv) {
		/*
		 * We need to clean up!
		 */
	}

	/*
	 * If the caller provides a private data pointer, save it in the 
	 * labelcl info structure(fastinfo).  This can be retrieved via
	 * hwgraph_fastinfo_get()
	 */
	if (info)
		hwgraph_fastinfo_set(new_devfs_handle, (arbitrary_info_t)info);
		
	return(new_devfs_handle);

}

/*
 * hwgraph_vertex_create - Create a vertex by giving it a temp name.
 */

/*
 * hwgraph_path_add - Create a directory node with the given path starting 
 * from the given devfs_handle_t.
 */
extern char * dev_to_name(devfs_handle_t, char *, uint);
int
hwgraph_path_add(devfs_handle_t  fromv,
		 char *path,
		 devfs_handle_t *new_de)
{

	unsigned int	namelen = strlen(path);
	int		rv;

	/*
	 * We need to handle the case when fromv is NULL ..
	 * in this case we need to create the path from the 
	 * hwgraph root!
	 */
	if (fromv == NULL)
		fromv = hwgraph_root;

	/*
	 * check the entry doesn't already exist, if it does
	 * then we simply want new_de to point to it (otherwise
	 * we'll overwrite the existing labelcl_info struct)
	 */
	rv = hwgraph_edge_get(fromv, path, new_de);
	if (rv)	{	/* couldn't find entry so we create it */
		*new_de = hwgraph_mk_dir(fromv, path, namelen, NULL);
		if (new_de == NULL)
			return(-1);
		else
			return(0);
	}
	else 
 		return(0);

}

/*
 * hwgraph_register  - Creates a file entry with devfs.
 *	Note that a file entry cannot have children .. it is like a 
 *	char|block special vertex in hwgraph.
 */
devfs_handle_t
hwgraph_register(devfs_handle_t de, const char *name,
                unsigned int namelen, unsigned int flags, 
		unsigned int major, unsigned int minor,
                umode_t mode, uid_t uid, gid_t gid, 
		struct file_operations *fops,
                void *info)
{

	int rv;
        void *labelcl_info = NULL;
        devfs_handle_t new_devfs_handle = NULL;
	devfs_handle_t parent = NULL;

        /*
         * Create the labelcl info structure for hwgraph compatiblity support.
         */
        labelcl_info = labelcl_info_create();
        if (!labelcl_info)
                return(NULL);

        /*
         * Create a devfs entry.
         */
        new_devfs_handle = devfs_register(de, name, flags, major,
				minor, mode, fops, labelcl_info);
        if (!new_devfs_handle) {
                labelcl_info_destroy((labelcl_info_t *)labelcl_info);
                return(NULL);
        }

	/*
	 * Get the parent handle.
	 */
	if (de == NULL)
		parent = devfs_get_parent (new_devfs_handle);
	else
		parent = de;
		
	/*
	 * To provide the same semantics as the hwgraph, set the connect point.
	 */
	rv = hwgraph_connectpt_set(new_devfs_handle, parent);
	if (rv) {
		/*
		 * We need to clean up!
		 */
		printk("HCL: Unable to set the connect point to it's parent 0x%p\n",
			new_devfs_handle);
	}

        /*
         * If the caller provides a private data pointer, save it in the 
         * labelcl info structure(fastinfo).  This can be retrieved via
         * hwgraph_fastinfo_get()
         */
        if (info)
                hwgraph_fastinfo_set(new_devfs_handle, (arbitrary_info_t)info);

        return(new_devfs_handle);

}


/*
 * hwgraph_mk_symlink - Create a symbolic link.
 */
int
hwgraph_mk_symlink(devfs_handle_t de, const char *name, unsigned int namelen,
                unsigned int flags, const char *link, unsigned int linklen, 
		devfs_handle_t *handle, void *info)
{

	void *labelcl_info = NULL;
	int status = 0;
	devfs_handle_t new_devfs_handle = NULL;

	/*
	 * Create the labelcl info structure for hwgraph compatiblity support.
	 */
	labelcl_info = labelcl_info_create();
	if (!labelcl_info)
		return(-1);

	/*
	 * Create a symbolic link devfs entry.
	 */
	status = devfs_mk_symlink(de, name, flags, link,
				&new_devfs_handle, labelcl_info);
	if ( (!new_devfs_handle) || (!status) ){
		labelcl_info_destroy((labelcl_info_t *)labelcl_info);
		return(-1);
	}

	/*
	 * If the caller provides a private data pointer, save it in the 
	 * labelcl info structure(fastinfo).  This can be retrieved via
	 * hwgraph_fastinfo_get()
	 */
	if (info)
		hwgraph_fastinfo_set(new_devfs_handle, (arbitrary_info_t)info);

	*handle = new_devfs_handle;