1/*
  2 *  file.c
  3 *
  4 *  Copyright (C) 1995, 1996 by Volker Lendecke
  5 *  Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache
  6 *
  7 */
  8
  9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 10
 11#include <asm/uaccess.h>
 12
 13#include <linux/time.h>
 14#include <linux/kernel.h>
 15#include <linux/errno.h>
 16#include <linux/fcntl.h>
 17#include <linux/stat.h>
 18#include <linux/mm.h>
 19#include <linux/vmalloc.h>
 20#include <linux/sched.h>
 21
 22#include "ncp_fs.h"
 23
 24static int ncp_fsync(struct file *file, loff_t start, loff_t end, int datasync)
 25{
 26	return filemap_write_and_wait_range(file->f_mapping, start, end);
 27}
 28
 29/*
 30 * Open a file with the specified read/write mode.
 31 */
 32int ncp_make_open(struct inode *inode, int right)
 33{
 34	int error;
 35	int access;
 36
 37	error = -EINVAL;
 38	if (!inode) {
 39		pr_err("%s: got NULL inode\n", __func__);
 40		goto out;
 41	}
 42
 43	ncp_dbg(1, "opened=%d, volume # %u, dir entry # %u\n",
 44		atomic_read(&NCP_FINFO(inode)->opened), 
 45		NCP_FINFO(inode)->volNumber, 
 46		NCP_FINFO(inode)->dirEntNum);
 47	error = -EACCES;
 48	mutex_lock(&NCP_FINFO(inode)->open_mutex);
 49	if (!atomic_read(&NCP_FINFO(inode)->opened)) {
 50		struct ncp_entry_info finfo;
 51		int result;
 52
 53		/* tries max. rights */
 54		finfo.access = O_RDWR;
 55		result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
 56					inode, NULL, OC_MODE_OPEN,
 57					0, AR_READ | AR_WRITE, &finfo);
 58		if (!result)
 59			goto update;
 60		/* RDWR did not succeeded, try readonly or writeonly as requested */
 61		switch (right) {
 62			case O_RDONLY:
 63				finfo.access = O_RDONLY;
 64				result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
 65					inode, NULL, OC_MODE_OPEN,
 66					0, AR_READ, &finfo);
 67				break;
 68			case O_WRONLY:
 69				finfo.access = O_WRONLY;
 70				result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
 71					inode, NULL, OC_MODE_OPEN,
 72					0, AR_WRITE, &finfo);
 73				break;
 74		}
 75		if (result) {
 76			ncp_vdbg("failed, result=%d\n", result);
 77			goto out_unlock;
 78		}
 79		/*
 80		 * Update the inode information.
 81		 */
 82	update:
 83		ncp_update_inode(inode, &finfo);
 84		atomic_set(&NCP_FINFO(inode)->opened, 1);
 85	}
 86
 87	access = NCP_FINFO(inode)->access;
 88	ncp_vdbg("file open, access=%x\n", access);
 89	if (access == right || access == O_RDWR) {
 90		atomic_inc(&NCP_FINFO(inode)->opened);
 91		error = 0;
 92	}
 93
 94out_unlock:
 95	mutex_unlock(&NCP_FINFO(inode)->open_mutex);
 96out:
 97	return error;
 98}
 99
100static ssize_t
101ncp_file_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
102{
103	struct dentry *dentry = file->f_path.dentry;
104	struct inode *inode = dentry->d_inode;
105	size_t already_read = 0;
106	off_t pos;
107	size_t bufsize;
108	int error;
109	void* freepage;
110	size_t freelen;
111
112	ncp_dbg(1, "enter %pd2\n", dentry);
113
114	pos = *ppos;
115
116	if ((ssize_t) count < 0) {
117		return -EINVAL;
118	}
119	if (!count)
120		return 0;
121	if (pos > inode->i_sb->s_maxbytes)
122		return 0;
123	if (pos + count > inode->i_sb->s_maxbytes) {
124		count = inode->i_sb->s_maxbytes - pos;
125	}
126
127	error = ncp_make_open(inode, O_RDONLY);
128	if (error) {
129		ncp_dbg(1, "open failed, error=%d\n", error);
130		return error;
131	}
132
133	bufsize = NCP_SERVER(inode)->buffer_size;
134
135	error = -EIO;
136	freelen = ncp_read_bounce_size(bufsize);
137	freepage = vmalloc(freelen);
138	if (!freepage)
139		goto outrel;
140	error = 0;
141	/* First read in as much as possible for each bufsize. */
142	while (already_read < count) {
143		int read_this_time;
144		size_t to_read = min_t(unsigned int,
145				     bufsize - (pos % bufsize),
146				     count - already_read);
147
148		error = ncp_read_bounce(NCP_SERVER(inode),
149			 	NCP_FINFO(inode)->file_handle,
150				pos, to_read, buf, &read_this_time, 
151				freepage, freelen);
152		if (error) {
153			error = -EIO;	/* NW errno -> Linux errno */
154			break;
155		}
156		pos += read_this_time;
157		buf += read_this_time;
158		already_read += read_this_time;
159
160		if (read_this_time != to_read) {
161			break;
162		}
163	}
164	vfree(freepage);
165
166	*ppos = pos;
167
168	file_accessed(file);
169
170	ncp_dbg(1, "exit %pd2\n", dentry);
171outrel:
172	ncp_inode_close(inode);		
173	return already_read ? already_read : error;
174}
175
176static ssize_t
177ncp_file_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
178{
179	struct dentry *dentry = file->f_path.dentry;
180	struct inode *inode = dentry->d_inode;
181	size_t already_written = 0;
182	off_t pos;
183	size_t bufsize;
184	int errno;
185	void* bouncebuffer;
186
187	ncp_dbg(1, "enter %pd2\n", dentry);
188	if ((ssize_t) count < 0)
189		return -EINVAL;
190	pos = *ppos;
191	if (file->f_flags & O_APPEND) {
192		pos = i_size_read(inode);
193	}
194
195	if (pos + count > MAX_NON_LFS && !(file->f_flags&O_LARGEFILE)) {
196		if (pos >= MAX_NON_LFS) {
197			return -EFBIG;
198		}
199		if (count > MAX_NON_LFS - (u32)pos) {
200			count = MAX_NON_LFS - (u32)pos;
201		}
202	}
203	if (pos >= inode->i_sb->s_maxbytes) {
204		if (count || pos > inode->i_sb->s_maxbytes) {
205			return -EFBIG;
206		}
207	}
208	if (pos + count > inode->i_sb->s_maxbytes) {
209		count = inode->i_sb->s_maxbytes - pos;
210	}
211	
212	if (!count)
213		return 0;
214	errno = ncp_make_open(inode, O_WRONLY);
215	if (errno) {
216		ncp_dbg(1, "open failed, error=%d\n", errno);
217		return errno;
218	}
219	bufsize = NCP_SERVER(inode)->buffer_size;
220
221	already_written = 0;
222
223	errno = file_update_time(file);
224	if (errno)
225		goto outrel;
226
227	bouncebuffer = vmalloc(bufsize);
228	if (!bouncebuffer) {
229		errno = -EIO;	/* -ENOMEM */
230		goto outrel;
231	}
232	while (already_written < count) {
233		int written_this_time;
234		size_t to_write = min_t(unsigned int,
235				      bufsize - (pos % bufsize),
236				      count - already_written);
237
238		if (copy_from_user(bouncebuffer, buf, to_write)) {
239			errno = -EFAULT;
240			break;
241		}
242		if (ncp_write_kernel(NCP_SERVER(inode), 
243		    NCP_FINFO(inode)->file_handle,
244		    pos, to_write, bouncebuffer, &written_this_time) != 0) {
245			errno = -EIO;
246			break;
247		}
248		pos += written_this_time;
249		buf += written_this_time;
250		already_written += written_this_time;
251
252		if (written_this_time != to_write) {
253			break;
254		}
255	}
256	vfree(bouncebuffer);
257
258	*ppos = pos;
259
260	if (pos > i_size_read(inode)) {
261		mutex_lock(&inode->i_mutex);
262		if (pos > i_size_read(inode))
263			i_size_write(inode, pos);
264		mutex_unlock(&inode->i_mutex);
265	}
266	ncp_dbg(1, "exit %pd2\n", dentry);
267outrel:
268	ncp_inode_close(inode);		
269	return already_written ? already_written : errno;
270}
271
272static int ncp_release(struct inode *inode, struct file *file) {
273	if (ncp_make_closed(inode)) {
274		ncp_dbg(1, "failed to close\n");
275	}
276	return 0;
277}
278
279const struct file_operations ncp_file_operations =
280{
281	.llseek		= generic_file_llseek,
282	.read		= ncp_file_read,
283	.write		= ncp_file_write,
284	.unlocked_ioctl	= ncp_ioctl,
285#ifdef CONFIG_COMPAT
286	.compat_ioctl	= ncp_compat_ioctl,
287#endif
288	.mmap		= ncp_mmap,
289	.release	= ncp_release,
290	.fsync		= ncp_fsync,
291};
292
293const struct inode_operations ncp_file_inode_operations =
294{
295	.setattr	= ncp_notify_change,
296};