/*
* linux/fs/9p/vfs_file.c
*
* This file contians vfs file ops for 9P2000.
*
* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
*
* 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 = v9fs_fid_lookup(file->f_dentry, FID_WALK);
struct v9fs_fid *v9newfid = NULL;
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 v9fid= %p\n", inode, file,
v9fid);
if (!v9fid) {
struct dentry *dentry = file->f_dentry;
dprintk(DEBUG_ERROR, "Couldn't resolve fid from dentry\n");
/* XXX - some duplication from lookup, generalize later */
/* basically vfs_lookup is too heavy weight */
v9fid = v9fs_fid_lookup(file->f_dentry, FID_OP);
if (!v9fid)
return -EBADF;
v9fid = v9fs_fid_lookup(dentry->d_parent, FID_WALK);
if (!v9fid)
return -EBADF;
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,
(char *)file->f_dentry->d_name.name, NULL);
if (result < 0) {
v9fs_put_idpool(newfid, &v9ses->fidpool);
dprintk(DEBUG_ERROR, "rewalk didn't work\n");
return -EBADF;
}
v9fid = v9fs_fid_create(dentry);
if (v9fid == NULL) {
dprintk(DEBUG_ERROR, "couldn't insert\n");
return -ENOMEM;
}
v9fid->fid = newfid;
}
if (v9fid->fidcreate) {
/* create case */
newfid = v9fid->fid;
iounit = v9fid->iounit;
v9fid->fidcreate = 0;
} else {
if (!S_ISDIR(inode->i_mode))
newfid = v9fid->fid;
else {
newfid = v9fs_get_idpool(&v9ses->fidpool);
if (newfid < 0) {
eprintk(KERN_WARNING, "allocation failed\n");
return -ENOSPC;
}
/* This would be a somewhat critical clone */
result =
v9fs_t_walk(v9ses, v9fid->fid, newfid, NULL,
&fcall);
if (result < 0) {
dprintk(DEBUG_ERROR, "clone error: %s\n",
FCALL_ERROR(fcall));
kfree(fcall);
return result;
}
v9newfid = v9fs_fid_create(file->f_dentry);
v9newfid->fid = newfid;
v9newfid->qid = v9fid->qid;
v9newfid->iounit = v9fid->iounit;
v9newfid->fidopen = 0;
v9newfid->fidclunked = 0;
v9newfid->v9ses = v9ses;
v9fid = v9newfid;
kfree(fcall);
}
/* 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) {
dprintk(DEBUG_ERROR,
"open failed, open_mode 0x%x: %s\n", open_mode,
FCALL_ERROR(fcall));
kfree(fcall);
return result;
}
iounit = fcall->params.ropen.iounit;
kfree(fcall);
}
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_fdatawrite(inode->i_mapping);
filemap_fdatawait(inode->i_mapping);
invalidate_inode_pages(&inode->i_data);
}
return res;
}
/**
* v9fs_read - read from a file (internal)
* @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_read(struct file *filp, char *buffer, 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;
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;
/* XXX - extra copy */
memcpy(buffer, fcall->params.rread.data, result);
count -= result;
buffer += result;
total += result;
kfree(fcall);
if (result < rsize)
break;
} while (count);
return total;
}
/**
* 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)
{
int retval = -1;
int ret = 0;
char *buffer;
buffer = kmalloc(count, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
retval = v9fs_read(filp, buffer, count, offset);
if (retval > 0) {
if ((ret = copy_to_user(data, buffer, retval)) != 0) {
dprintk(DEBUG_ERROR, "Problem copying to user %d\n",
ret);
retval = ret;
}
}
kfree(buffer);
return retval;
}
/**
* v9fs_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_write(struct file *filp, char *buffer, 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", buffer, (int)count,
(int)*offset);
rsize = v9ses->maxdata - V9FS_IOHDRSZ;
if (v9fid->iounit != 0 && rsize > v9fid->iounit)
rsize = v9fid->iounit;
dump_data(buffer, count);
do {
if (count < rsize)
rsize = count;
result =
v9fs_t_write(v9ses, fid, *offset, rsize, buffer, &fcall);
if (result < 0) {
eprintk(KERN_ERR, "error while writing: %s(%d)\n",
FCALL_ERROR(fcall), result);
kfree(fcall);
return result;
} else
*offset += result;
kfree(fcall);
if (result != rsize) {
eprintk(KERN_ERR,
"short write: v9fs_t_write returned %d\n",
result);
break;
}
count -= result;
buffer += result;
total += result;
} 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)
{
int ret = -1;
char *buffer;
buffer = kmalloc(count, GFP_KERNEL);
if (buffer == NULL)
return -ENOMEM;
ret = copy_from_user(buffer, data, count);
if (ret) {
dprintk(DEBUG_ERROR, "Problem copying from user\n");
ret = -EFAULT;
} else {
ret = v9fs_write(filp, buffer, count, offset);
}
kfree(buffer);
return ret;
}
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,
};
