[linux-2.6-block.git] / fs / smbfs / file.c

/*
 *  file.c
 *
 *  Copyright (C) 1995, 1996, 1997 by Paal-Kr. Engstad and Volker Lendecke
 *  Copyright (C) 1997 by Volker Lendecke
 *
 *  Please add a note about your changes to smbfs in the ChangeLog file.
 */

#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/slab.h>
#include <linux/pagemap.h>
#include <linux/smp_lock.h>
#include <linux/net.h>

#include <asm/uaccess.h>
#include <asm/system.h>

#include <linux/smbno.h>
#include <linux/smb_fs.h>

#include "smb_debug.h"
#include "proto.h"

static int
smb_fsync(struct file *file, struct dentry * dentry, int datasync)
{
	struct smb_sb_info *server = server_from_dentry(dentry);
	int result;

	VERBOSE("sync file %s/%s\n", DENTRY_PATH(dentry));

	/*
	 * The VFS will writepage() all dirty pages for us, but we
	 * should send a SMBflush to the server, letting it know that
	 * we want things synchronized with actual storage.
	 *
	 * Note: this function requires all pages to have been written already
	 *       (should be ok with writepage_sync)
	 */
	result = smb_proc_flush(server, SMB_I(dentry->d_inode)->fileid);
	return result;
}

/*
 * Read a page synchronously.
 */
static int
smb_readpage_sync(struct dentry *dentry, struct page *page)
{
	char *buffer = kmap(page);
	loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
	struct smb_sb_info *server = server_from_dentry(dentry);
	unsigned int rsize = smb_get_rsize(server);
	int count = PAGE_SIZE;
	int result;

	VERBOSE("file %s/%s, count=%d@%Ld, rsize=%d\n",
		DENTRY_PATH(dentry), count, offset, rsize);

	result = smb_open(dentry, SMB_O_RDONLY);
	if (result < 0)
		goto io_error;

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

		result = server->ops->read(dentry->d_inode,offset,rsize,buffer);
		if (result < 0)
			goto io_error;

		count -= result;
		offset += result;
		buffer += result;
		dentry->d_inode->i_atime =
			current_fs_time(dentry->d_inode->i_sb);
		if (result < rsize)
			break;
	} while (count);

	memset(buffer, 0, count);
	flush_dcache_page(page);
	SetPageUptodate(page);
	result = 0;

io_error:
	kunmap(page);
	unlock_page(page);
	return result;
}

/*
 * We are called with the page locked and we unlock it when done.
 */
static int
smb_readpage(struct file *file, struct page *page)
{
	int		error;
	struct dentry  *dentry = file->f_dentry;

	page_cache_get(page);
	error = smb_readpage_sync(dentry, page);
	page_cache_release(page);
	return error;
}

/*
 * Write a page synchronously.
 * Offset is the data offset within the page.
 */
static int
smb_writepage_sync(struct inode *inode, struct page *page,
		   unsigned long pageoffset, unsigned int count)
{
	loff_t offset;
	char *buffer = kmap(page) + pageoffset;
	struct smb_sb_info *server = server_from_inode(inode);
	unsigned int wsize = smb_get_wsize(server);
	int ret = 0;

	offset = ((loff_t)page->index << PAGE_CACHE_SHIFT) + pageoffset;
	VERBOSE("file ino=%ld, fileid=%d, count=%d@%Ld, wsize=%d\n",
		inode->i_ino, SMB_I(inode)->fileid, count, offset, wsize);

	do {
		int write_ret;

		if (count < wsize)
			wsize = count;

		write_ret = server->ops->write(inode, offset, wsize, buffer);
		if (write_ret < 0) {
			PARANOIA("failed write, wsize=%d, write_ret=%d\n",
				 wsize, write_ret);
			ret = write_ret;
			break;
		}
		/* N.B. what if result < wsize?? */
#ifdef SMBFS_PARANOIA
		if (write_ret < wsize)
			PARANOIA("short write, wsize=%d, write_ret=%d\n",
				 wsize, write_ret);
#endif
		buffer += wsize;
		offset += wsize;
		count -= wsize;
		/*
		 * Update the inode now rather than waiting for a refresh.
		 */
		inode->i_mtime = inode->i_atime = current_fs_time(inode->i_sb);
		SMB_I(inode)->flags |= SMB_F_LOCALWRITE;
		if (offset > inode->i_size)
			inode->i_size = offset;
	} while (count);

	kunmap(page);
	return ret;
}

/*
 * Write a page to the server. This will be used for NFS swapping only
 * (for now), and we currently do this synchronously only.
 *
 * We are called with the page locked and we unlock it when done.
 */
static int
smb_writepage(struct page *page, struct writeback_control *wbc)
{
	struct address_space *mapping = page->mapping;
	struct inode *inode;
	unsigned long end_index;
	unsigned offset = PAGE_CACHE_SIZE;
	int err;

	BUG_ON(!mapping);
	inode = mapping->host;
	BUG_ON(!inode);

	end_index = inode->i_size >> PAGE_CACHE_SHIFT;

	/* easy case */
	if (page->index < end_index)
		goto do_it;
	/* things got complicated... */
	offset = inode->i_size & (PAGE_CACHE_SIZE-1);
	/* OK, are we completely out? */
	if (page->index >= end_index+1 || !offset)
		return 0; /* truncated - don't care */
do_it:
	page_cache_get(page);
	err = smb_writepage_sync(inode, page, 0, offset);
	SetPageUptodate(page);
	unlock_page(page);
	page_cache_release(page);
	return err;
}

static int
smb_updatepage(struct file *file, struct page *page, unsigned long offset,
	       unsigned int count)
{
	struct dentry *dentry = file->f_dentry;

	DEBUG1("(%s/%s %d@%lld)\n", DENTRY_PATH(dentry), count,
		((unsigned long long)page->index << PAGE_CACHE_SHIFT) + offset);

	return smb_writepage_sync(dentry->d_inode, page, offset, count);
}

static ssize_t
smb_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
			unsigned long nr_segs, loff_t pos)
{
	struct file * file = iocb->ki_filp;
	struct dentry * dentry = file->f_dentry;
	ssize_t	status;

	VERBOSE("file %s/%s, count=%lu@%lu\n", DENTRY_PATH(dentry),
		(unsigned long) iocb->ki_left, (unsigned long) pos);

	status = smb_revalidate_inode(dentry);
	if (status) {
		PARANOIA("%s/%s validation failed, error=%Zd\n",
			 DENTRY_PATH(dentry), status);
		goto out;
	}

	VERBOSE("before read, size=%ld, flags=%x, atime=%ld\n",
		(long)dentry->d_inode->i_size,
		dentry->d_inode->i_flags, dentry->d_inode->i_atime);

	status = generic_file_aio_read(iocb, iov, nr_segs, pos);
out:
	return status;
}

static int
smb_file_mmap(struct file * file, struct vm_area_struct * vma)
{
	struct dentry * dentry = file->f_dentry;
	int	status;

	VERBOSE("file %s/%s, address %lu - %lu\n",
		DENTRY_PATH(dentry), vma->vm_start, vma->vm_end);

	status = smb_revalidate_inode(dentry);
	if (status) {
		PARANOIA("%s/%s validation failed, error=%d\n",
			 DENTRY_PATH(dentry), status);
		goto out;
	}
	status = generic_file_mmap(file, vma);
out:
	return status;
}

static ssize_t
smb_file_sendfile(struct file *file, loff_t *ppos,
		  size_t count, read_actor_t actor, void *target)
{
	struct dentry *dentry = file->f_dentry;
	ssize_t status;

	VERBOSE("file %s/%s, pos=%Ld, count=%d\n",
		DENTRY_PATH(dentry), *ppos, count);

	status = smb_revalidate_inode(dentry);
	if (status) {
		PARANOIA("%s/%s validation failed, error=%Zd\n",
			 DENTRY_PATH(dentry), status);
		goto out;
	}
	status = generic_file_sendfile(file, ppos, count, actor, target);
out:
	return status;
}

/*
 * This does the "real" work of the write. The generic routine has
 * allocated the page, locked it, done all the page alignment stuff
 * calculations etc. Now we should just copy the data from user
 * space and write it back to the real medium..
 *
 * If the writer ends up delaying the write, the writer needs to
 * increment the page use counts until he is done with the page.
 */
static int smb_prepare_write(struct file *file, struct page *page, 
			     unsigned offset, unsigned to)
{
	return 0;
}

static int smb_commit_write(struct file *file, struct page *page,
			    unsigned offset, unsigned to)
{
	int status;

	status = -EFAULT;
	lock_kernel();
	status = smb_updatepage(file, page, offset, to-offset);
	unlock_kernel();
	return status;
}

const struct address_space_operations smb_file_aops = {
	.readpage = smb_readpage,
	.writepage = smb_writepage,
	.prepare_write = smb_prepare_write,
	.commit_write = smb_commit_write
};

/* 
 * Write to a file (through the page cache).
 */
static ssize_t
smb_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
			       unsigned long nr_segs, loff_t pos)
{
	struct file * file = iocb->ki_filp;
	struct dentry * dentry = file->f_dentry;
	ssize_t	result;

	VERBOSE("file %s/%s, count=%lu@%lu\n",
		DENTRY_PATH(dentry),
		(unsigned long) iocb->ki_left, (unsigned long) pos);

	result = smb_revalidate_inode(dentry);
	if (result) {
		PARANOIA("%s/%s validation failed, error=%Zd\n",
			 DENTRY_PATH(dentry), result);
		goto out;
	}

	result = smb_open(dentry, SMB_O_WRONLY);
	if (result)
		goto out;

	if (iocb->ki_left > 0) {
		result = generic_file_aio_write(iocb, iov, nr_segs, pos);
		VERBOSE("pos=%ld, size=%ld, mtime=%ld, atime=%ld\n",
			(long) file->f_pos, (long) dentry->d_inode->i_size,
			dentry->d_inode->i_mtime, dentry->d_inode->i_atime);
	}
out:
	return result;
}

static int
smb_file_open(struct inode *inode, struct file * file)
{
	int result;
	struct dentry *dentry = file->f_dentry;
	int smb_mode = (file->f_mode & O_ACCMODE) - 1;

	lock_kernel();
	result = smb_open(dentry, smb_mode);
	if (result)
		goto out;
	SMB_I(inode)->openers++;
out:
	unlock_kernel();
	return result;
}

static int
smb_file_release(struct inode *inode, struct file * file)
{
	lock_kernel();
	if (!--SMB_I(inode)->openers) {
		/* We must flush any dirty pages now as we won't be able to
		   write anything after close. mmap can trigger this.
		   "openers" should perhaps include mmap'ers ... */
		filemap_write_and_wait(inode->i_mapping);
		smb_close(inode);
	}
	unlock_kernel();
	return 0;
}

/*
 * Check whether the required access is compatible with
 * an inode's permission. SMB doesn't recognize superuser
 * privileges, so we need our own check for this.
 */
static int
smb_file_permission(struct inode *inode, int mask, struct nameidata *nd)
{
	int mode = inode->i_mode;
	int error = 0;

	VERBOSE("mode=%x, mask=%x\n", mode, mask);

	/* Look at user permissions */
	mode >>= 6;
	if ((mode & 7 & mask) != mask)
		error = -EACCES;
	return error;
}

const struct file_operations smb_file_operations =
{
	.llseek		= remote_llseek,
	.read		= do_sync_read,
	.aio_read	= smb_file_aio_read,
	.write		= do_sync_write,
	.aio_write	= smb_file_aio_write,
	.ioctl		= smb_ioctl,
	.mmap		= smb_file_mmap,
	.open		= smb_file_open,
	.release	= smb_file_release,
	.fsync		= smb_fsync,
	.sendfile	= smb_file_sendfile,
};

struct inode_operations smb_file_inode_operations =
{
	.permission	= smb_file_permission,
	.getattr	= smb_getattr,
	.setattr	= smb_notify_change,
};
Commit	Line	Data
1da177e4 LT	1	/*
	2	* file.c
	3	*
	4	* Copyright (C) 1995, 1996, 1997 by Paal-Kr. Engstad and Volker Lendecke
	5	* Copyright (C) 1997 by Volker Lendecke
	6	*
	7	* Please add a note about your changes to smbfs in the ChangeLog file.
	8	*/
	9
	10	#include <linux/time.h>
	11	#include <linux/kernel.h>
	12	#include <linux/errno.h>
	13	#include <linux/fcntl.h>
	14	#include <linux/stat.h>
	15	#include <linux/mm.h>
	16	#include <linux/slab.h>
	17	#include <linux/pagemap.h>
	18	#include <linux/smp_lock.h>
	19	#include <linux/net.h>
	20
	21	#include <asm/uaccess.h>
	22	#include <asm/system.h>
	23
	24	#include <linux/smbno.h>
	25	#include <linux/smb_fs.h>
	26
	27	#include "smb_debug.h"
	28	#include "proto.h"
	29
	30	static int
	31	smb_fsync(struct file file, struct dentry dentry, int datasync)
	32	{
	33	struct smb_sb_info *server = server_from_dentry(dentry);
	34	int result;
	35
	36	VERBOSE("sync file %s/%s\n", DENTRY_PATH(dentry));
	37
	38	/*
	39	* The VFS will writepage() all dirty pages for us, but we
	40	* should send a SMBflush to the server, letting it know that
	41	* we want things synchronized with actual storage.
	42	*
	43	* Note: this function requires all pages to have been written already
	44	* (should be ok with writepage_sync)
	45	*/
	46	result = smb_proc_flush(server, SMB_I(dentry->d_inode)->fileid);
	47	return result;
	48	}
	49
	50	/*
	51	* Read a page synchronously.
	52	*/
	53	static int
	54	smb_readpage_sync(struct dentry dentry, struct page page)
	55	{
	56	char *buffer = kmap(page);
	57	loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
	58	struct smb_sb_info *server = server_from_dentry(dentry);
	59	unsigned int rsize = smb_get_rsize(server);
	60	int count = PAGE_SIZE;
	61	int result;
	62
	63	VERBOSE("file %s/%s, count=%d@%Ld, rsize=%d\n",
	64	DENTRY_PATH(dentry), count, offset, rsize);
65
66	result = smb_open(dentry, SMB_O_RDONLY);
67	if (result < 0)
68	goto io_error;
69
70	do {
71	if (count < rsize)
72	rsize = count;
73
74	result = server->ops->read(dentry->d_inode,offset,rsize,buffer);
75	if (result < 0)
76	goto io_error;
77
78	count -= result;
79	offset += result;
80	buffer += result;
81	dentry->d_inode->i_atime =
82	current_fs_time(dentry->d_inode->i_sb);
83	if (result < rsize)
84	break;
85	} while (count);
86
87	memset(buffer, 0, count);
88	flush_dcache_page(page);
89	SetPageUptodate(page);
90	result = 0;
91
92	io_error:
93	kunmap(page);
94	unlock_page(page);
95	return result;
96	}
97
98	/*
99	* We are called with the page locked and we unlock it when done.
100	*/
101	static int
102	smb_readpage(struct file file, struct page page)
103	{
104	int error;
105	struct dentry *dentry = file->f_dentry;
106
107	page_cache_get(page);
108	error = smb_readpage_sync(dentry, page);
109	page_cache_release(page);
110	return error;
111	}
112
113	/*
114	* Write a page synchronously.
115	* Offset is the data offset within the page.
116	*/
117	static int
118	smb_writepage_sync(struct inode inode, struct page page,
119	unsigned long pageoffset, unsigned int count)
120	{
121	loff_t offset;
122	char *buffer = kmap(page) + pageoffset;
123	struct smb_sb_info *server = server_from_inode(inode);
124	unsigned int wsize = smb_get_wsize(server);
125	int ret = 0;
126
127	offset = ((loff_t)page->index << PAGE_CACHE_SHIFT) + pageoffset;
128	VERBOSE("file ino=%ld, fileid=%d, count=%d@%Ld, wsize=%d\n",
129	inode->i_ino, SMB_I(inode)->fileid, count, offset, wsize);
130
131	do {
132	int write_ret;
133
134	if (count < wsize)
135	wsize = count;
136
137	write_ret = server->ops->write(inode, offset, wsize, buffer);
138	if (write_ret < 0) {
139	PARANOIA("failed write, wsize=%d, write_ret=%d\n",
140	wsize, write_ret);
141	ret = write_ret;
142	break;
143	}
144	/* N.B. what if result < wsize?? */
145	#ifdef SMBFS_PARANOIA
146	if (write_ret < wsize)
147	PARANOIA("short write, wsize=%d, write_ret=%d\n",
148	wsize, write_ret);
149	#endif
150	buffer += wsize;
151	offset += wsize;
152	count -= wsize;
153	/*
154	* Update the inode now rather than waiting for a refresh.
155	*/
156	inode->i_mtime = inode->i_atime = current_fs_time(inode->i_sb);
157	SMB_I(inode)->flags \|= SMB_F_LOCALWRITE;
158	if (offset > inode->i_size)
159	inode->i_size = offset;
160	} while (count);
161
162	kunmap(page);
163	return ret;
164	}
165
166	/*
167	* Write a page to the server. This will be used for NFS swapping only
168	* (for now), and we currently do this synchronously only.
169	*
170	* We are called with the page locked and we unlock it when done.
171	*/
172	static int
173	smb_writepage(struct page page, struct writeback_control wbc)
174	{
175	struct address_space *mapping = page->mapping;
176	struct inode *inode;
177	unsigned long end_index;
178	unsigned offset = PAGE_CACHE_SIZE;
179	int err;
180
5df0d312	181	BUG_ON(!mapping);
1da177e4	182	inode = mapping->host;
5df0d312	183	BUG_ON(!inode);
1da177e4 LT	184
	185	end_index = inode->i_size >> PAGE_CACHE_SHIFT;
	186
	187	/* easy case */
	188	if (page->index < end_index)
	189	goto do_it;
	190	/* things got complicated... */
	191	offset = inode->i_size & (PAGE_CACHE_SIZE-1);
	192	/* OK, are we completely out? */
	193	if (page->index >= end_index+1 \|\| !offset)
	194	return 0; /* truncated - don't care */
	195	do_it:
	196	page_cache_get(page);
	197	err = smb_writepage_sync(inode, page, 0, offset);
	198	SetPageUptodate(page);
	199	unlock_page(page);
	200	page_cache_release(page);
	201	return err;
	202	}
	203
	204	static int
	205	smb_updatepage(struct file file, struct page page, unsigned long offset,
	206	unsigned int count)
	207	{
	208	struct dentry *dentry = file->f_dentry;
	209
54b21a79 AM	210	DEBUG1("(%s/%s %d@%lld)\n", DENTRY_PATH(dentry), count,
54b21a79 AM	211	((unsigned long long)page->index << PAGE_CACHE_SHIFT) + offset);
1da177e4 LT	212
	213	return smb_writepage_sync(dentry->d_inode, page, offset, count);
	214	}
	215
	216	static ssize_t
543ade1f BP	217	smb_file_aio_read(struct kiocb iocb, const struct iovec iov,
543ade1f BP	218	unsigned long nr_segs, loff_t pos)
1da177e4	219	{
543ade1f	220	struct file * file = iocb->ki_filp;
1da177e4 LT	221	struct dentry * dentry = file->f_dentry;
	222	ssize_t status;
	223
	224	VERBOSE("file %s/%s, count=%lu@%lu\n", DENTRY_PATH(dentry),
543ade1f	225	(unsigned long) iocb->ki_left, (unsigned long) pos);
1da177e4 LT	226
	227	status = smb_revalidate_inode(dentry);
	228	if (status) {
	229	PARANOIA("%s/%s validation failed, error=%Zd\n",
	230	DENTRY_PATH(dentry), status);
	231	goto out;
	232	}
	233
	234	VERBOSE("before read, size=%ld, flags=%x, atime=%ld\n",
	235	(long)dentry->d_inode->i_size,
	236	dentry->d_inode->i_flags, dentry->d_inode->i_atime);
	237
543ade1f	238	status = generic_file_aio_read(iocb, iov, nr_segs, pos);
1da177e4 LT	239	out:
	240	return status;
	241	}
	242
	243	static int
	244	smb_file_mmap(struct file * file, struct vm_area_struct * vma)
	245	{
	246	struct dentry * dentry = file->f_dentry;
	247	int status;
	248
	249	VERBOSE("file %s/%s, address %lu - %lu\n",
	250	DENTRY_PATH(dentry), vma->vm_start, vma->vm_end);
	251
	252	status = smb_revalidate_inode(dentry);
	253	if (status) {
	254	PARANOIA("%s/%s validation failed, error=%d\n",
	255	DENTRY_PATH(dentry), status);
	256	goto out;
	257	}
	258	status = generic_file_mmap(file, vma);
	259	out:
	260	return status;
	261	}
	262
	263	static ssize_t
	264	smb_file_sendfile(struct file file, loff_t ppos,
	265	size_t count, read_actor_t actor, void *target)
	266	{
	267	struct dentry *dentry = file->f_dentry;
	268	ssize_t status;
	269
	270	VERBOSE("file %s/%s, pos=%Ld, count=%d\n",
	271	DENTRY_PATH(dentry), *ppos, count);
	272
	273	status = smb_revalidate_inode(dentry);
	274	if (status) {
	275	PARANOIA("%s/%s validation failed, error=%Zd\n",
	276	DENTRY_PATH(dentry), status);
	277	goto out;
	278	}
	279	status = generic_file_sendfile(file, ppos, count, actor, target);
	280	out:
	281	return status;
	282	}
	283
	284	/*
	285	* This does the "real" work of the write. The generic routine has
	286	* allocated the page, locked it, done all the page alignment stuff
	287	* calculations etc. Now we should just copy the data from user
	288	* space and write it back to the real medium..
	289	*
	290	* If the writer ends up delaying the write, the writer needs to
	291	* increment the page use counts until he is done with the page.
	292	*/
	293	static int smb_prepare_write(struct file file, struct page page,
	294	unsigned offset, unsigned to)
	295	{
	296	return 0;
	297	}
	298
	299	static int smb_commit_write(struct file file, struct page page,
	300	unsigned offset, unsigned to)
	301	{
	302	int status;
303
304	status = -EFAULT;
305	lock_kernel();
306	status = smb_updatepage(file, page, offset, to-offset);
307	unlock_kernel();
308	return status;
309	}
310
f5e54d6e	311	const struct address_space_operations smb_file_aops = {
1da177e4 LT	312	.readpage = smb_readpage,
	313	.writepage = smb_writepage,
	314	.prepare_write = smb_prepare_write,
	315	.commit_write = smb_commit_write
	316	};
	317
	318	/*
	319	* Write to a file (through the page cache).
	320	*/
	321	static ssize_t
543ade1f BP	322	smb_file_aio_write(struct kiocb iocb, const struct iovec iov,
543ade1f BP	323	unsigned long nr_segs, loff_t pos)
1da177e4	324	{
543ade1f	325	struct file * file = iocb->ki_filp;
1da177e4 LT	326	struct dentry * dentry = file->f_dentry;
	327	ssize_t result;
	328
	329	VERBOSE("file %s/%s, count=%lu@%lu\n",
	330	DENTRY_PATH(dentry),
543ade1f	331	(unsigned long) iocb->ki_left, (unsigned long) pos);
1da177e4 LT	332
	333	result = smb_revalidate_inode(dentry);
	334	if (result) {
	335	PARANOIA("%s/%s validation failed, error=%Zd\n",
	336	DENTRY_PATH(dentry), result);
	337	goto out;
	338	}
	339
	340	result = smb_open(dentry, SMB_O_WRONLY);
	341	if (result)
	342	goto out;
	343
543ade1f BP	344	if (iocb->ki_left > 0) {
543ade1f BP	345	result = generic_file_aio_write(iocb, iov, nr_segs, pos);
1da177e4 LT	346	VERBOSE("pos=%ld, size=%ld, mtime=%ld, atime=%ld\n",
	347	(long) file->f_pos, (long) dentry->d_inode->i_size,
	348	dentry->d_inode->i_mtime, dentry->d_inode->i_atime);
	349	}
	350	out:
	351	return result;
	352	}
	353
	354	static int
	355	smb_file_open(struct inode inode, struct file file)
	356	{
	357	int result;
	358	struct dentry *dentry = file->f_dentry;
	359	int smb_mode = (file->f_mode & O_ACCMODE) - 1;
	360
	361	lock_kernel();
	362	result = smb_open(dentry, smb_mode);
	363	if (result)
	364	goto out;
	365	SMB_I(inode)->openers++;
	366	out:
	367	unlock_kernel();
	368	return result;
	369	}
	370
	371	static int
	372	smb_file_release(struct inode inode, struct file file)
	373	{
	374	lock_kernel();
	375	if (!--SMB_I(inode)->openers) {
	376	/* We must flush any dirty pages now as we won't be able to
	377	write anything after close. mmap can trigger this.
	378	"openers" should perhaps include mmap'ers ... */
28fd1298	379	filemap_write_and_wait(inode->i_mapping);
1da177e4 LT	380	smb_close(inode);
	381	}
	382	unlock_kernel();
	383	return 0;
	384	}
	385
	386	/*
	387	* Check whether the required access is compatible with
	388	* an inode's permission. SMB doesn't recognize superuser
	389	* privileges, so we need our own check for this.
	390	*/
	391	static int
	392	smb_file_permission(struct inode inode, int mask, struct nameidata nd)
	393	{
	394	int mode = inode->i_mode;
	395	int error = 0;
	396
	397	VERBOSE("mode=%x, mask=%x\n", mode, mask);
	398
	399	/* Look at user permissions */
	400	mode >>= 6;
	401	if ((mode & 7 & mask) != mask)
	402	error = -EACCES;
	403	return error;
	404	}
	405
4b6f5d20	406	const struct file_operations smb_file_operations =
1da177e4 LT	407	{
1da177e4 LT	408	.llseek = remote_llseek,
543ade1f BP	409	.read = do_sync_read,
	410	.aio_read = smb_file_aio_read,
	411	.write = do_sync_write,
	412	.aio_write = smb_file_aio_write,
1da177e4 LT	413	.ioctl = smb_ioctl,
	414	.mmap = smb_file_mmap,
	415	.open = smb_file_open,
	416	.release = smb_file_release,
	417	.fsync = smb_fsync,
	418	.sendfile = smb_file_sendfile,
	419	};
	420
	421	struct inode_operations smb_file_inode_operations =
	422	{
	423	.permission = smb_file_permission,
	424	.getattr = smb_getattr,
	425	.setattr = smb_notify_change,
	426	};