/* *  linux/fs/nfs/file.c * *  Copyright (C) 1992  Rick Sladkey * *  nfs regular file handling functions */#include <asm/segment.h>#include <asm/system.h>#include <linux/sched.h>#include <linux/kernel.h>#include <linux/errno.h>#include <linux/fcntl.h>#include <linux/stat.h>#include <linux/mm.h>#include <linux/nfs_fs.h>#include <linux/malloc.h>static int nfs_file_read(struct inode *, struct file *, char *, int);static int nfs_file_write(struct inode *, struct file *, char *, int);static int nfs_fsync(struct inode *, struct file *);extern int nfs_mmap(struct inode * inode, struct file * file,	      unsigned long addr, size_t len, int prot, unsigned long off);static struct file_operations nfs_file_operations = {	NULL,			/* lseek - default */	nfs_file_read,		/* read */	nfs_file_write,		/* write */	NULL,			/* readdir - bad */	NULL,			/* select - default */	NULL,			/* ioctl - default */	nfs_mmap,		/* mmap */	NULL,			/* no special open is needed */	NULL,			/* release */	nfs_fsync,		/* fsync */};struct inode_operations nfs_file_inode_operations = {	&nfs_file_operations,	/* default file operations */	NULL,			/* create */	NULL,			/* lookup */	NULL,			/* link */	NULL,			/* unlink */	NULL,			/* symlink */	NULL,			/* mkdir */	NULL,			/* rmdir */	NULL,			/* mknod */	NULL,			/* rename */	NULL,			/* readlink */	NULL,			/* follow_link */	NULL,			/* bmap */	NULL			/* truncate */};static int nfs_fsync(struct inode *inode, struct file *file){	return 0;}static int nfs_file_read(struct inode *inode, struct file *file, char *buf,			 int count){	int result;	int hunk;	int i;	int n;	struct nfs_fattr fattr;	char *data;	off_t pos;	if (!inode) {		printk("nfs_file_read: inode = NULL\n");		return -EINVAL;	}	if (!S_ISREG(inode->i_mode)) {		printk("nfs_file_read: read from non-file, mode %07o\n",			inode->i_mode);		return -EINVAL;	}	pos = file->f_pos;	if (file->f_pos + count > inode->i_size)		count = inode->i_size - pos;	if (count <= 0)		return 0;	n = NFS_SERVER(inode)->rsize;	data = (char *) kmalloc(n, GFP_KERNEL);	for (i = 0; i < count; i += n) {		hunk = count - i;		if (hunk > n)			hunk = n;		result = nfs_proc_read(NFS_SERVER(inode), NFS_FH(inode), 			pos, hunk, data, &fattr);		if (result < 0) {			kfree_s(data, n);			return result;		}		memcpy_tofs(buf, data, result);		pos += result;		buf += result;		if (result < n) {			i += result;			break;		}	}	file->f_pos = pos;	kfree_s(data, n);	nfs_refresh_inode(inode, &fattr);	return i;}static int nfs_file_write(struct inode *inode, struct file *file, char *buf,			  int count){	int result;	int hunk;	int i;	int n;	struct nfs_fattr fattr;	char *data;	int pos;	if (!inode) {		printk("nfs_file_write: inode = NULL\n");		return -EINVAL;	}	if (!S_ISREG(inode->i_mode)) {		printk("nfs_file_write: write to non-file, mode %07o\n",			inode->i_mode);		return -EINVAL;	}	if (count <= 0)		return 0;	pos = file->f_pos;	if (file->f_flags & O_APPEND)		pos = inode->i_size;	n = NFS_SERVER(inode)->wsize;	data = (char *) kmalloc(n, GFP_KERNEL);	for (i = 0; i < count; i += n) {		hunk = count - i;		if (hunk >= n)			hunk = n;		memcpy_fromfs(data, buf, hunk);		result = nfs_proc_write(NFS_SERVER(inode), NFS_FH(inode), 			pos, hunk, data, &fattr);		if (result < 0) {			kfree_s(data, n);			return result;		}		pos += hunk;		buf += hunk;		if (hunk < n) {			i += hunk;			break;		}	}	file->f_pos = pos;	kfree_s(data, n);	nfs_refresh_inode(inode, &fattr);	return i;}