[deliverable/linux.git] / fs / 9p / fid.c

/*
 * V9FS FID Management
 *
 *  Copyright (C) 2005, 2006 by Eric Van Hensbergen <ericvh@gmail.com>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2
 *  as published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to:
 *  Free Software Foundation
 *  51 Franklin Street, Fifth Floor
 *  Boston, MA  02111-1301  USA
 *
 */

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/idr.h>

#include "debug.h"
#include "v9fs.h"
#include "9p.h"
#include "v9fs_vfs.h"
#include "fid.h"

/**
 * v9fs_fid_insert - add a fid to a dentry
 * @fid: fid to add
 * @dentry: dentry that it is being added to
 *
 */

int v9fs_fid_insert(struct v9fs_fid *fid, struct dentry *dentry)
{
	struct list_head *fid_list = (struct list_head *)dentry->d_fsdata;
	dprintk(DEBUG_9P, "fid %d (%p) dentry %s (%p)\n", fid->fid, fid,
		dentry->d_iname, dentry);
	if (dentry->d_fsdata == NULL) {
		dentry->d_fsdata =
		    kmalloc(sizeof(struct list_head), GFP_KERNEL);
		if (dentry->d_fsdata == NULL) {
			dprintk(DEBUG_ERROR, "Out of memory\n");
			return -ENOMEM;
		}
		fid_list = (struct list_head *)dentry->d_fsdata;
		INIT_LIST_HEAD(fid_list);	/* Initialize list head */
	}

	fid->uid = current->uid;
	list_add(&fid->list, fid_list);
	return 0;
}

/**
 * v9fs_fid_create - allocate a FID structure
 * @dentry - dentry to link newly created fid to
 *
 */

struct v9fs_fid *v9fs_fid_create(struct v9fs_session_info *v9ses, int fid)
{
	struct v9fs_fid *new;

	dprintk(DEBUG_9P, "fid create fid %d\n", fid);
	new = kmalloc(sizeof(struct v9fs_fid), GFP_KERNEL);
	if (new == NULL) {
		dprintk(DEBUG_ERROR, "Out of Memory\n");
		return ERR_PTR(-ENOMEM);
	}

	new->fid = fid;
	new->v9ses = v9ses;
	new->fidopen = 0;
	new->fidclunked = 0;
	new->iounit = 0;
	new->rdir_pos = 0;
	new->rdir_fcall = NULL;
	INIT_LIST_HEAD(&new->list);

	return new;
}

/**
 * v9fs_fid_destroy - deallocate a FID structure
 * @fid: fid to destroy
 *
 */

void v9fs_fid_destroy(struct v9fs_fid *fid)
{
	list_del(&fid->list);
	kfree(fid);
}

/**
 * v9fs_fid_lookup - retrieve the right fid from a  particular dentry
 * @dentry: dentry to look for fid in
 * @type: intent of lookup (operation or traversal)
 *
 * find a fid in the dentry
 *
 * TODO: only match fids that have the same uid as current user
 *
 */

struct v9fs_fid *v9fs_fid_lookup(struct dentry *dentry)
{
	struct list_head *fid_list = (struct list_head *)dentry->d_fsdata;
	struct v9fs_fid *return_fid = NULL;

	dprintk(DEBUG_9P, " dentry: %s (%p)\n", dentry->d_iname, dentry);

	if (fid_list)
		return_fid = list_entry(fid_list->next, struct v9fs_fid, list);

	if (!return_fid) {
		dprintk(DEBUG_ERROR, "Couldn't find a fid in dentry\n");
	}

	return return_fid;
}
Commit	Line	Data
3ed8491c EVH	1	/*
	2	* V9FS FID Management
	3	*
46f6dac2	4	* Copyright (C) 2005, 2006 by Eric Van Hensbergen <ericvh@gmail.com>
3ed8491c EVH	5	*
3ed8491c EVH	6	* This program is free software; you can redistribute it and/or modify
42e8c509 EVH	7	* it under the terms of the GNU General Public License version 2
42e8c509 EVH	8	* as published by the Free Software Foundation.
3ed8491c EVH	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to:
	17	* Free Software Foundation
	18	* 51 Franklin Street, Fifth Floor
	19	* Boston, MA 02111-1301 USA
	20	*
	21	*/
	22
3ed8491c EVH	23	#include <linux/module.h>
	24	#include <linux/errno.h>
	25	#include <linux/fs.h>
914e2637	26	#include <linux/sched.h>
3ed8491c EVH	27	#include <linux/idr.h>
	28
	29	#include "debug.h"
	30	#include "v9fs.h"
	31	#include "9p.h"
	32	#include "v9fs_vfs.h"
3ed8491c EVH	33	#include "fid.h"
	34
	35	/**
	36	* v9fs_fid_insert - add a fid to a dentry
	37	* @fid: fid to add
	38	* @dentry: dentry that it is being added to
	39	*
	40	*/
	41
6a3124a3	42	int v9fs_fid_insert(struct v9fs_fid fid, struct dentry dentry)
3ed8491c EVH	43	{
	44	struct list_head fid_list = (struct list_head )dentry->d_fsdata;
	45	dprintk(DEBUG_9P, "fid %d (%p) dentry %s (%p)\n", fid->fid, fid,
	46	dentry->d_iname, dentry);
	47	if (dentry->d_fsdata == NULL) {
	48	dentry->d_fsdata =
	49	kmalloc(sizeof(struct list_head), GFP_KERNEL);
	50	if (dentry->d_fsdata == NULL) {
	51	dprintk(DEBUG_ERROR, "Out of memory\n");
	52	return -ENOMEM;
	53	}
	54	fid_list = (struct list_head *)dentry->d_fsdata;
	55	INIT_LIST_HEAD(fid_list); /* Initialize list head */
	56	}
	57
	58	fid->uid = current->uid;
3ed8491c EVH	59	list_add(&fid->list, fid_list);
	60	return 0;
	61	}
	62
	63	/**
	64	* v9fs_fid_create - allocate a FID structure
	65	* @dentry - dentry to link newly created fid to
	66	*
	67	*/
	68
6a3124a3	69	struct v9fs_fid v9fs_fid_create(struct v9fs_session_info v9ses, int fid)
3ed8491c EVH	70	{
	71	struct v9fs_fid *new;
	72
6a3124a3	73	dprintk(DEBUG_9P, "fid create fid %d\n", fid);
3ed8491c EVH	74	new = kmalloc(sizeof(struct v9fs_fid), GFP_KERNEL);
	75	if (new == NULL) {
	76	dprintk(DEBUG_ERROR, "Out of Memory\n");
	77	return ERR_PTR(-ENOMEM);
	78	}
	79
0b8dd177 LI	80	new->fid = fid;
0b8dd177 LI	81	new->v9ses = v9ses;
3ed8491c	82	new->fidopen = 0;
3ed8491c EVH	83	new->fidclunked = 0;
3ed8491c EVH	84	new->iounit = 0;
0b8dd177 LI	85	new->rdir_pos = 0;
0b8dd177 LI	86	new->rdir_fcall = NULL;
6a3124a3	87	INIT_LIST_HEAD(&new->list);
3ed8491c	88
46f6dac2	89	return new;
3ed8491c EVH	90	}
	91
	92	/**
	93	* v9fs_fid_destroy - deallocate a FID structure
	94	* @fid: fid to destroy
	95	*
	96	*/
	97
	98	void v9fs_fid_destroy(struct v9fs_fid *fid)
	99	{
	100	list_del(&fid->list);
	101	kfree(fid);
	102	}
	103
	104	/**
	105	* v9fs_fid_lookup - retrieve the right fid from a particular dentry
	106	* @dentry: dentry to look for fid in
	107	* @type: intent of lookup (operation or traversal)
	108	*
46f6dac2 EVH	109	* find a fid in the dentry
	110	*
	111	* TODO: only match fids that have the same uid as current user
3ed8491c EVH	112	*
	113	*/
	114
0b8dd177	115	struct v9fs_fid v9fs_fid_lookup(struct dentry dentry)
3ed8491c EVH	116	{
3ed8491c EVH	117	struct list_head fid_list = (struct list_head )dentry->d_fsdata;
3ed8491c	118	struct v9fs_fid *return_fid = NULL;
3ed8491c	119
0b8dd177	120	dprintk(DEBUG_9P, " dentry: %s (%p)\n", dentry->d_iname, dentry);
3ed8491c	121
6a3124a3 LI	122	if (fid_list)
6a3124a3 LI	123	return_fid = list_entry(fid_list->next, struct v9fs_fid, list);
3ed8491c EVH	124
3ed8491c EVH	125	if (!return_fid) {
46f6dac2	126	dprintk(DEBUG_ERROR, "Couldn't find a fid in dentry\n");
0b8dd177	127	}
3ed8491c	128
0b8dd177 LI	129	return return_fid;
0b8dd177 LI	130	}