file.c 5.74 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4 5 6 7 8
/*
 *  file.c
 *
 *  Copyright (C) 1995, 1996 by Volker Lendecke
 *  Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache
 *
 */

9 10
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

11
#include <linux/uaccess.h>
Linus Torvalds's avatar
Linus Torvalds committed
12 13 14 15 16 17 18 19

#include <linux/time.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/fcntl.h>
#include <linux/stat.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
Alexey Dobriyan's avatar
Alexey Dobriyan committed
20
#include <linux/sched.h>
Linus Torvalds's avatar
Linus Torvalds committed
21

22
#include "ncp_fs.h"
Linus Torvalds's avatar
Linus Torvalds committed
23

24
static int ncp_fsync(struct file *file, loff_t start, loff_t end, int datasync)
Linus Torvalds's avatar
Linus Torvalds committed
25
{
26
	return file_write_and_wait_range(file, start, end);
Linus Torvalds's avatar
Linus Torvalds committed
27 28 29 30 31 32 33 34 35 36 37 38
}

/*
 * Open a file with the specified read/write mode.
 */
int ncp_make_open(struct inode *inode, int right)
{
	int error;
	int access;

	error = -EINVAL;
	if (!inode) {
39
		pr_err("%s: got NULL inode\n", __func__);
Linus Torvalds's avatar
Linus Torvalds committed
40 41 42
		goto out;
	}

43
	ncp_dbg(1, "opened=%d, volume # %u, dir entry # %u\n",
Linus Torvalds's avatar
Linus Torvalds committed
44 45 46 47
		atomic_read(&NCP_FINFO(inode)->opened), 
		NCP_FINFO(inode)->volNumber, 
		NCP_FINFO(inode)->dirEntNum);
	error = -EACCES;
Ingo Molnar's avatar
Ingo Molnar committed
48
	mutex_lock(&NCP_FINFO(inode)->open_mutex);
Linus Torvalds's avatar
Linus Torvalds committed
49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75
	if (!atomic_read(&NCP_FINFO(inode)->opened)) {
		struct ncp_entry_info finfo;
		int result;

		/* tries max. rights */
		finfo.access = O_RDWR;
		result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
					inode, NULL, OC_MODE_OPEN,
					0, AR_READ | AR_WRITE, &finfo);
		if (!result)
			goto update;
		/* RDWR did not succeeded, try readonly or writeonly as requested */
		switch (right) {
			case O_RDONLY:
				finfo.access = O_RDONLY;
				result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
					inode, NULL, OC_MODE_OPEN,
					0, AR_READ, &finfo);
				break;
			case O_WRONLY:
				finfo.access = O_WRONLY;
				result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
					inode, NULL, OC_MODE_OPEN,
					0, AR_WRITE, &finfo);
				break;
		}
		if (result) {
76
			ncp_vdbg("failed, result=%d\n", result);
Linus Torvalds's avatar
Linus Torvalds committed
77 78 79 80 81 82 83 84 85 86 87
			goto out_unlock;
		}
		/*
		 * Update the inode information.
		 */
	update:
		ncp_update_inode(inode, &finfo);
		atomic_set(&NCP_FINFO(inode)->opened, 1);
	}

	access = NCP_FINFO(inode)->access;
88
	ncp_vdbg("file open, access=%x\n", access);
Linus Torvalds's avatar
Linus Torvalds committed
89 90 91 92 93 94
	if (access == right || access == O_RDWR) {
		atomic_inc(&NCP_FINFO(inode)->opened);
		error = 0;
	}

out_unlock:
Ingo Molnar's avatar
Ingo Molnar committed
95
	mutex_unlock(&NCP_FINFO(inode)->open_mutex);
Linus Torvalds's avatar
Linus Torvalds committed
96 97 98 99 100
out:
	return error;
}

static ssize_t
101
ncp_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
Linus Torvalds's avatar
Linus Torvalds committed
102
{
103
	struct file *file = iocb->ki_filp;
Al Viro's avatar
Al Viro committed
104
	struct inode *inode = file_inode(file);
Linus Torvalds's avatar
Linus Torvalds committed
105
	size_t already_read = 0;
106
	off_t pos = iocb->ki_pos;
Linus Torvalds's avatar
Linus Torvalds committed
107 108
	size_t bufsize;
	int error;
109
	void *freepage;
Linus Torvalds's avatar
Linus Torvalds committed
110 111
	size_t freelen;

Al Viro's avatar
Al Viro committed
112
	ncp_dbg(1, "enter %pD2\n", file);
Linus Torvalds's avatar
Linus Torvalds committed
113

114
	if (!iov_iter_count(to))
Linus Torvalds's avatar
Linus Torvalds committed
115 116 117
		return 0;
	if (pos > inode->i_sb->s_maxbytes)
		return 0;
118
	iov_iter_truncate(to, inode->i_sb->s_maxbytes - pos);
Linus Torvalds's avatar
Linus Torvalds committed
119 120 121

	error = ncp_make_open(inode, O_RDONLY);
	if (error) {
122
		ncp_dbg(1, "open failed, error=%d\n", error);
Linus Torvalds's avatar
Linus Torvalds committed
123 124 125 126 127 128 129 130 131 132 133 134
		return error;
	}

	bufsize = NCP_SERVER(inode)->buffer_size;

	error = -EIO;
	freelen = ncp_read_bounce_size(bufsize);
	freepage = vmalloc(freelen);
	if (!freepage)
		goto outrel;
	error = 0;
	/* First read in as much as possible for each bufsize. */
135
	while (iov_iter_count(to)) {
Linus Torvalds's avatar
Linus Torvalds committed
136
		int read_this_time;
137
		size_t to_read = min_t(size_t,
Linus Torvalds's avatar
Linus Torvalds committed
138
				     bufsize - (pos % bufsize),
139
				     iov_iter_count(to));
Linus Torvalds's avatar
Linus Torvalds committed
140 141 142

		error = ncp_read_bounce(NCP_SERVER(inode),
			 	NCP_FINFO(inode)->file_handle,
143
				pos, to_read, to, &read_this_time, 
Linus Torvalds's avatar
Linus Torvalds committed
144 145 146 147 148 149 150 151
				freepage, freelen);
		if (error) {
			error = -EIO;	/* NW errno -> Linux errno */
			break;
		}
		pos += read_this_time;
		already_read += read_this_time;

152
		if (read_this_time != to_read)
Linus Torvalds's avatar
Linus Torvalds committed
153 154 155 156
			break;
	}
	vfree(freepage);

157
	iocb->ki_pos = pos;
Linus Torvalds's avatar
Linus Torvalds committed
158 159 160

	file_accessed(file);

Al Viro's avatar
Al Viro committed
161
	ncp_dbg(1, "exit %pD2\n", file);
Linus Torvalds's avatar
Linus Torvalds committed
162 163 164 165 166 167
outrel:
	ncp_inode_close(inode);		
	return already_read ? already_read : error;
}

static ssize_t
168
ncp_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
Linus Torvalds's avatar
Linus Torvalds committed
169
{
170
	struct file *file = iocb->ki_filp;
Al Viro's avatar
Al Viro committed
171
	struct inode *inode = file_inode(file);
Linus Torvalds's avatar
Linus Torvalds committed
172 173 174
	size_t already_written = 0;
	size_t bufsize;
	int errno;
175
	void *bouncebuffer;
176
	off_t pos;
Linus Torvalds's avatar
Linus Torvalds committed
177

Al Viro's avatar
Al Viro committed
178
	ncp_dbg(1, "enter %pD2\n", file);
179 180
	errno = generic_write_checks(iocb, from);
	if (errno <= 0)
181 182
		return errno;

Linus Torvalds's avatar
Linus Torvalds committed
183 184
	errno = ncp_make_open(inode, O_WRONLY);
	if (errno) {
185
		ncp_dbg(1, "open failed, error=%d\n", errno);
Linus Torvalds's avatar
Linus Torvalds committed
186 187 188 189
		return errno;
	}
	bufsize = NCP_SERVER(inode)->buffer_size;

190 191 192 193
	errno = file_update_time(file);
	if (errno)
		goto outrel;

Linus Torvalds's avatar
Linus Torvalds committed
194 195 196 197 198
	bouncebuffer = vmalloc(bufsize);
	if (!bouncebuffer) {
		errno = -EIO;	/* -ENOMEM */
		goto outrel;
	}
199
	pos = iocb->ki_pos;
200
	while (iov_iter_count(from)) {
Linus Torvalds's avatar
Linus Torvalds committed
201
		int written_this_time;
202
		size_t to_write = min_t(size_t,
203
				      bufsize - (pos % bufsize),
204
				      iov_iter_count(from));
Linus Torvalds's avatar
Linus Torvalds committed
205

206
		if (!copy_from_iter_full(bouncebuffer, to_write, from)) {
Linus Torvalds's avatar
Linus Torvalds committed
207 208 209 210 211 212 213 214 215 216 217 218
			errno = -EFAULT;
			break;
		}
		if (ncp_write_kernel(NCP_SERVER(inode), 
		    NCP_FINFO(inode)->file_handle,
		    pos, to_write, bouncebuffer, &written_this_time) != 0) {
			errno = -EIO;
			break;
		}
		pos += written_this_time;
		already_written += written_this_time;

219
		if (written_this_time != to_write)
Linus Torvalds's avatar
Linus Torvalds committed
220 221 222 223
			break;
	}
	vfree(bouncebuffer);

224
	iocb->ki_pos = pos;
Linus Torvalds's avatar
Linus Torvalds committed
225

Petr Vandrovec's avatar
Petr Vandrovec committed
226
	if (pos > i_size_read(inode)) {
Al Viro's avatar
Al Viro committed
227
		inode_lock(inode);
Petr Vandrovec's avatar
Petr Vandrovec committed
228 229
		if (pos > i_size_read(inode))
			i_size_write(inode, pos);
Al Viro's avatar
Al Viro committed
230
		inode_unlock(inode);
Linus Torvalds's avatar
Linus Torvalds committed
231
	}
Al Viro's avatar
Al Viro committed
232
	ncp_dbg(1, "exit %pD2\n", file);
Linus Torvalds's avatar
Linus Torvalds committed
233 234 235 236 237 238 239
outrel:
	ncp_inode_close(inode);		
	return already_written ? already_written : errno;
}

static int ncp_release(struct inode *inode, struct file *file) {
	if (ncp_make_closed(inode)) {
240
		ncp_dbg(1, "failed to close\n");
Linus Torvalds's avatar
Linus Torvalds committed
241 242 243 244
	}
	return 0;
}

245
const struct file_operations ncp_file_operations =
Linus Torvalds's avatar
Linus Torvalds committed
246
{
Petr Vandrovec's avatar
Petr Vandrovec committed
247
	.llseek		= generic_file_llseek,
248 249
	.read_iter	= ncp_file_read_iter,
	.write_iter	= ncp_file_write_iter,
John Kacur's avatar
John Kacur committed
250
	.unlocked_ioctl	= ncp_ioctl,
251 252 253
#ifdef CONFIG_COMPAT
	.compat_ioctl	= ncp_compat_ioctl,
#endif
Linus Torvalds's avatar
Linus Torvalds committed
254 255 256 257 258
	.mmap		= ncp_mmap,
	.release	= ncp_release,
	.fsync		= ncp_fsync,
};

259
const struct inode_operations ncp_file_inode_operations =
Linus Torvalds's avatar
Linus Torvalds committed
260 261 262
{
	.setattr	= ncp_notify_change,
};