[linux.git] / fs / 9p / vfs_file.c

/*
 *  linux/fs/9p/vfs_file.c
 *
 * This file contians vfs file ops for 9P2000.
 *
 *  Copyright (C) 2004 by Eric Van Hensbergen <[email protected]>
 *  Copyright (C) 2002 by Ron Minnich <[email protected]>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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/file.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/smp_lock.h>
#include <linux/inet.h>
#include <linux/version.h>
#include <linux/list.h>
#include <asm/uaccess.h>
#include <linux/idr.h>

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

/**
 * v9fs_file_open - open a file (or directory)
 * @inode: inode to be opened
 * @file: file being opened
 *
 */

int v9fs_file_open(struct inode *inode, struct file *file)
{
	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
	struct v9fs_fid *v9fid, *fid;
	struct v9fs_fcall *fcall = NULL;
	int open_mode = 0;
	unsigned int iounit = 0;
	int newfid = -1;
	long result = -1;

	dprintk(DEBUG_VFS, "inode: %p file: %p \n", inode, file);

	v9fid = v9fs_fid_get_created(file->f_dentry);
	if (!v9fid)
		v9fid = v9fs_fid_lookup(file->f_dentry);

	if (!v9fid) {
		dprintk(DEBUG_ERROR, "Couldn't resolve fid from dentry\n");
		return -EBADF;
	}

	if (!v9fid->fidcreate) {
		fid = kmalloc(sizeof(struct v9fs_fid), GFP_KERNEL);
		if (fid == NULL) {
			dprintk(DEBUG_ERROR, "Out of Memory\n");
			return -ENOMEM;
		}

		fid->fidopen = 0;
		fid->fidcreate = 0;
		fid->fidclunked = 0;
		fid->iounit = 0;
		fid->v9ses = v9ses;

		newfid = v9fs_get_idpool(&v9ses->fidpool);
		if (newfid < 0) {
			eprintk(KERN_WARNING, "newfid fails!\n");
			return -ENOSPC;
		}

		result =
		    v9fs_t_walk(v9ses, v9fid->fid, newfid, NULL, NULL);

		if (result < 0) {
			v9fs_put_idpool(newfid, &v9ses->fidpool);
			dprintk(DEBUG_ERROR, "rewalk didn't work\n");
			return -EBADF;
		}

		fid->fid = newfid;
		v9fid = fid;
		/* TODO: do special things for O_EXCL, O_NOFOLLOW, O_SYNC */
		/* translate open mode appropriately */
		open_mode = file->f_flags & 0x3;

		if (file->f_flags & O_EXCL)
			open_mode |= V9FS_OEXCL;

		if (v9ses->extended) {
			if (file->f_flags & O_TRUNC)
				open_mode |= V9FS_OTRUNC;

			if (file->f_flags & O_APPEND)
				open_mode |= V9FS_OAPPEND;
		}

		result = v9fs_t_open(v9ses, newfid, open_mode, &fcall);
		if (result < 0) {
			PRINT_FCALL_ERROR("open failed", fcall);
			kfree(fcall);
			return result;
		}

		iounit = fcall->params.ropen.iounit;
		kfree(fcall);
	} else {
		/* create case */
		newfid = v9fid->fid;
		iounit = v9fid->iounit;
		v9fid->fidcreate = 0;
	}

	file->private_data = v9fid;

	v9fid->rdir_pos = 0;
	v9fid->rdir_fcall = NULL;
	v9fid->fidopen = 1;
	v9fid->filp = file;
	v9fid->iounit = iounit;

	return 0;
}

/**
 * v9fs_file_lock - lock a file (or directory)
 * @inode: inode to be opened
 * @file: file being opened
 *
 * XXX - this looks like a local only lock, we should extend into 9P
 *       by using open exclusive
 */

static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
{
	int res = 0;
	struct inode *inode = filp->f_dentry->d_inode;

	dprintk(DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);

	/* No mandatory locks */
	if ((inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
		return -ENOLCK;

	if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
		filemap_write_and_wait(inode->i_mapping);
		invalidate_inode_pages(&inode->i_data);
	}

	return res;
}

/**
 * v9fs_file_read - read from a file
 * @filep: file pointer to read
 * @data: data buffer to read data into
 * @count: size of buffer
 * @offset: offset at which to read data
 *
 */
static ssize_t
v9fs_file_read(struct file *filp, char __user * data, size_t count,
	       loff_t * offset)
{
	struct inode *inode = filp->f_dentry->d_inode;
	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
	struct v9fs_fid *v9f = filp->private_data;
	struct v9fs_fcall *fcall = NULL;
	int fid = v9f->fid;
	int rsize = 0;
	int result = 0;
	int total = 0;
	int n;

	dprintk(DEBUG_VFS, "\n");

	rsize = v9ses->maxdata - V9FS_IOHDRSZ;
	if (v9f->iounit != 0 && rsize > v9f->iounit)
		rsize = v9f->iounit;

	do {
		if (count < rsize)
			rsize = count;

		result = v9fs_t_read(v9ses, fid, *offset, rsize, &fcall);

		if (result < 0) {
			printk(KERN_ERR "9P2000: v9fs_t_read returned %d\n",
			       result);

			kfree(fcall);
			return total;
		} else
			*offset += result;

		n = copy_to_user(data, fcall->params.rread.data, result);
		if (n) {
			dprintk(DEBUG_ERROR, "Problem copying to user %d\n", n);
			kfree(fcall);
			return -EFAULT;
		}

		count -= result;
		data += result;
		total += result;

		kfree(fcall);

		if (result < rsize)
			break;
	} while (count);

	return total;
}

/**
 * v9fs_file_write - write to a file
 * @filep: file pointer to write
 * @data: data buffer to write data from
 * @count: size of buffer
 * @offset: offset at which to write data
 *
 */

static ssize_t
v9fs_file_write(struct file *filp, const char __user * data,
		size_t count, loff_t * offset)
{
	struct inode *inode = filp->f_dentry->d_inode;
	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
	struct v9fs_fid *v9fid = filp->private_data;
	struct v9fs_fcall *fcall;
	int fid = v9fid->fid;
	int result = -EIO;
	int rsize = 0;
	int total = 0;

	dprintk(DEBUG_VFS, "data %p count %d offset %x\n", data, (int)count,
		(int)*offset);
	rsize = v9ses->maxdata - V9FS_IOHDRSZ;
	if (v9fid->iounit != 0 && rsize > v9fid->iounit)
		rsize = v9fid->iounit;

	do {
		if (count < rsize)
			rsize = count;

		result = v9fs_t_write(v9ses, fid, *offset, rsize, data, &fcall);
		if (result < 0) {
			PRINT_FCALL_ERROR("error while writing", fcall);
			kfree(fcall);
			return result;
		} else
			*offset += result;

		kfree(fcall);
		fcall = NULL;

		if (result != rsize) {
			eprintk(KERN_ERR,
				"short write: v9fs_t_write returned %d\n",
				result);
			break;
		}

		count -= result;
		data += result;
		total += result;
	} while (count);

	if(inode->i_mapping->nrpages)
		invalidate_inode_pages2(inode->i_mapping);

	return total;
}

struct file_operations v9fs_file_operations = {
	.llseek = generic_file_llseek,
	.read = v9fs_file_read,
	.write = v9fs_file_write,
	.open = v9fs_file_open,
	.release = v9fs_dir_release,
	.lock = v9fs_file_lock,
	.mmap = generic_file_mmap,
};
Commit	Line	Data
e69e7fe5 EVH	1	/*
	2	* linux/fs/9p/vfs_file.c
	3	*
	4	* This file contians vfs file ops for 9P2000.
	5	*
	6	* Copyright (C) 2004 by Eric Van Hensbergen <[email protected]>
	7	* Copyright (C) 2002 by Ron Minnich <[email protected]>
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License as published by
	11	* the Free Software Foundation; either version 2 of the License, or
	12	* (at your option) any later version.
	13	*
	14	* This program is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	* GNU General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU General Public License
	20	* along with this program; if not, write to:
	21	* Free Software Foundation
	22	* 51 Franklin Street, Fifth Floor
	23	* Boston, MA 02111-1301 USA
	24	*
	25	*/
	26
	27	#include <linux/module.h>
	28	#include <linux/errno.h>
	29	#include <linux/fs.h>
	30	#include <linux/file.h>
	31	#include <linux/stat.h>
	32	#include <linux/string.h>
	33	#include <linux/smp_lock.h>
	34	#include <linux/inet.h>
531b1094	35	#include <linux/version.h>
e69e7fe5 EVH	36	#include <linux/list.h>
	37	#include <asm/uaccess.h>
	38	#include <linux/idr.h>
	39
	40	#include "debug.h"
	41	#include "v9fs.h"
	42	#include "9p.h"
	43	#include "v9fs_vfs.h"
	44	#include "fid.h"
	45
	46	/**
	47	* v9fs_file_open - open a file (or directory)
	48	* @inode: inode to be opened
	49	* @file: file being opened
	50	*
	51	*/
	52
	53	int v9fs_file_open(struct inode inode, struct file file)
	54	{
	55	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
0b8dd177	56	struct v9fs_fid v9fid, fid;
e69e7fe5 EVH	57	struct v9fs_fcall *fcall = NULL;
	58	int open_mode = 0;
	59	unsigned int iounit = 0;
	60	int newfid = -1;
	61	long result = -1;
	62
0b8dd177 LI	63	dprintk(DEBUG_VFS, "inode: %p file: %p \n", inode, file);
	64
	65	v9fid = v9fs_fid_get_created(file->f_dentry);
	66	if (!v9fid)
	67	v9fid = v9fs_fid_lookup(file->f_dentry);
e69e7fe5 EVH	68
e69e7fe5 EVH	69	if (!v9fid) {
e69e7fe5	70	dprintk(DEBUG_ERROR, "Couldn't resolve fid from dentry\n");
0b8dd177 LI	71	return -EBADF;
0b8dd177 LI	72	}
e69e7fe5	73
0b8dd177 LI	74	if (!v9fid->fidcreate) {
	75	fid = kmalloc(sizeof(struct v9fs_fid), GFP_KERNEL);
	76	if (fid == NULL) {
	77	dprintk(DEBUG_ERROR, "Out of Memory\n");
	78	return -ENOMEM;
	79	}
e69e7fe5	80
0b8dd177 LI	81	fid->fidopen = 0;
	82	fid->fidcreate = 0;
	83	fid->fidclunked = 0;
	84	fid->iounit = 0;
	85	fid->v9ses = v9ses;
e69e7fe5 EVH	86
	87	newfid = v9fs_get_idpool(&v9ses->fidpool);
	88	if (newfid < 0) {
	89	eprintk(KERN_WARNING, "newfid fails!\n");
	90	return -ENOSPC;
	91	}
	92
	93	result =
0b8dd177 LI	94	v9fs_t_walk(v9ses, v9fid->fid, newfid, NULL, NULL);
0b8dd177 LI	95
e69e7fe5 EVH	96	if (result < 0) {
	97	v9fs_put_idpool(newfid, &v9ses->fidpool);
	98	dprintk(DEBUG_ERROR, "rewalk didn't work\n");
	99	return -EBADF;
	100	}
	101
0b8dd177 LI	102	fid->fid = newfid;
0b8dd177 LI	103	v9fid = fid;
e69e7fe5 EVH	104	/* TODO: do special things for O_EXCL, O_NOFOLLOW, O_SYNC */
	105	/* translate open mode appropriately */
	106	open_mode = file->f_flags & 0x3;
	107
	108	if (file->f_flags & O_EXCL)
	109	open_mode \|= V9FS_OEXCL;
	110
	111	if (v9ses->extended) {
	112	if (file->f_flags & O_TRUNC)
	113	open_mode \|= V9FS_OTRUNC;
	114
	115	if (file->f_flags & O_APPEND)
	116	open_mode \|= V9FS_OAPPEND;
	117	}
	118
	119	result = v9fs_t_open(v9ses, newfid, open_mode, &fcall);
	120	if (result < 0) {
531b1094	121	PRINT_FCALL_ERROR("open failed", fcall);
e69e7fe5 EVH	122	kfree(fcall);
	123	return result;
	124	}
	125
	126	iounit = fcall->params.ropen.iounit;
	127	kfree(fcall);
0b8dd177 LI	128	} else {
	129	/* create case */
	130	newfid = v9fid->fid;
	131	iounit = v9fid->iounit;
	132	v9fid->fidcreate = 0;
e69e7fe5 EVH	133	}
e69e7fe5 EVH	134
e69e7fe5 EVH	135	file->private_data = v9fid;
	136
	137	v9fid->rdir_pos = 0;
	138	v9fid->rdir_fcall = NULL;
	139	v9fid->fidopen = 1;
	140	v9fid->filp = file;
	141	v9fid->iounit = iounit;
	142
	143	return 0;
	144	}
	145
	146	/**
	147	* v9fs_file_lock - lock a file (or directory)
	148	* @inode: inode to be opened
	149	* @file: file being opened
	150	*
	151	* XXX - this looks like a local only lock, we should extend into 9P
	152	* by using open exclusive
	153	*/
	154
	155	static int v9fs_file_lock(struct file filp, int cmd, struct file_lock fl)
	156	{
	157	int res = 0;
	158	struct inode *inode = filp->f_dentry->d_inode;
	159
	160	dprintk(DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
	161
	162	/* No mandatory locks */
	163	if ((inode->i_mode & (S_ISGID \| S_IXGRP)) == S_ISGID)
	164	return -ENOLCK;
	165
	166	if ((IS_SETLK(cmd) \|\| IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
28fd1298	167	filemap_write_and_wait(inode->i_mapping);
e69e7fe5 EVH	168	invalidate_inode_pages(&inode->i_data);
	169	}
	170
	171	return res;
	172	}
	173
	174	/**
19cba8ab	175	* v9fs_file_read - read from a file
e69e7fe5 EVH	176	* @filep: file pointer to read
	177	* @data: data buffer to read data into
	178	* @count: size of buffer
	179	* @offset: offset at which to read data
	180	*
	181	*/
e69e7fe5	182	static ssize_t
19cba8ab LI	183	v9fs_file_read(struct file filp, char __user data, size_t count,
19cba8ab LI	184	loff_t * offset)
e69e7fe5 EVH	185	{
	186	struct inode *inode = filp->f_dentry->d_inode;
	187	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
	188	struct v9fs_fid *v9f = filp->private_data;
	189	struct v9fs_fcall *fcall = NULL;
	190	int fid = v9f->fid;
	191	int rsize = 0;
	192	int result = 0;
	193	int total = 0;
19cba8ab	194	int n;
e69e7fe5 EVH	195
	196	dprintk(DEBUG_VFS, "\n");
	197
	198	rsize = v9ses->maxdata - V9FS_IOHDRSZ;
	199	if (v9f->iounit != 0 && rsize > v9f->iounit)
	200	rsize = v9f->iounit;
	201
	202	do {
	203	if (count < rsize)
	204	rsize = count;
	205
	206	result = v9fs_t_read(v9ses, fid, *offset, rsize, &fcall);
	207
	208	if (result < 0) {
	209	printk(KERN_ERR "9P2000: v9fs_t_read returned %d\n",
	210	result);
	211
	212	kfree(fcall);
	213	return total;
	214	} else
	215	*offset += result;
	216
19cba8ab LI	217	n = copy_to_user(data, fcall->params.rread.data, result);
	218	if (n) {
	219	dprintk(DEBUG_ERROR, "Problem copying to user %d\n", n);
	220	kfree(fcall);
	221	return -EFAULT;
	222	}
	223
e69e7fe5	224	count -= result;
19cba8ab	225	data += result;
e69e7fe5 EVH	226	total += result;
	227
	228	kfree(fcall);
	229
	230	if (result < rsize)
	231	break;
	232	} while (count);
	233
	234	return total;
	235	}
	236
	237	/**
19cba8ab	238	* v9fs_file_write - write to a file
e69e7fe5 EVH	239	* @filep: file pointer to write
	240	* @data: data buffer to write data from
	241	* @count: size of buffer
	242	* @offset: offset at which to write data
	243	*
	244	*/
	245
	246	static ssize_t
19cba8ab LI	247	v9fs_file_write(struct file filp, const char __user data,
19cba8ab LI	248	size_t count, loff_t * offset)
e69e7fe5 EVH	249	{
	250	struct inode *inode = filp->f_dentry->d_inode;
	251	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
	252	struct v9fs_fid *v9fid = filp->private_data;
	253	struct v9fs_fcall *fcall;
	254	int fid = v9fid->fid;
	255	int result = -EIO;
	256	int rsize = 0;
	257	int total = 0;
	258
19cba8ab	259	dprintk(DEBUG_VFS, "data %p count %d offset %x\n", data, (int)count,
e69e7fe5 EVH	260	(int)*offset);
	261	rsize = v9ses->maxdata - V9FS_IOHDRSZ;
	262	if (v9fid->iounit != 0 && rsize > v9fid->iounit)
	263	rsize = v9fid->iounit;
	264
e69e7fe5 EVH	265	do {
	266	if (count < rsize)
	267	rsize = count;
	268
531b1094	269	result = v9fs_t_write(v9ses, fid, *offset, rsize, data, &fcall);
e69e7fe5	270	if (result < 0) {
531b1094	271	PRINT_FCALL_ERROR("error while writing", fcall);
e69e7fe5 EVH	272	kfree(fcall);
	273	return result;
	274	} else
	275	*offset += result;
	276
	277	kfree(fcall);
19cba8ab	278	fcall = NULL;
e69e7fe5 EVH	279
	280	if (result != rsize) {
	281	eprintk(KERN_ERR,
	282	"short write: v9fs_t_write returned %d\n",
	283	result);
	284	break;
	285	}
	286
	287	count -= result;
19cba8ab	288	data += result;
e69e7fe5 EVH	289	total += result;
	290	} while (count);
	291
147b31cf EVH	292	if(inode->i_mapping->nrpages)
	293	invalidate_inode_pages2(inode->i_mapping);
	294
e69e7fe5 EVH	295	return total;
	296	}
	297
e69e7fe5 EVH	298	struct file_operations v9fs_file_operations = {
	299	.llseek = generic_file_llseek,
	300	.read = v9fs_file_read,
	301	.write = v9fs_file_write,
	302	.open = v9fs_file_open,
	303	.release = v9fs_dir_release,
	304	.lock = v9fs_file_lock,
147b31cf	305	.mmap = generic_file_mmap,
e69e7fe5	306	};