summaryrefslogtreecommitdiff
path: root/fs/nfs/nfs4file.c
blob: 619eca34e70fcc258b04b824f62d95b2f142765a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
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
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
/*
 *  linux/fs/nfs/file.c
 *
 *  Copyright (C) 1992  Rick Sladkey
 */
#include <linux/fs.h>
#include <linux/falloc.h>
#include <linux/nfs_fs.h>
#include "internal.h"
#include "fscache.h"
#include "pnfs.h"

#ifdef CONFIG_NFS_V4_2
#include "nfs42.h"
#endif

#define NFSDBG_FACILITY		NFSDBG_FILE

static int
nfs4_file_open(struct inode *inode, struct file *filp)
{
	struct nfs_open_context *ctx;
	struct dentry *dentry = filp->f_path.dentry;
	struct dentry *parent = NULL;
	struct inode *dir;
	unsigned openflags = filp->f_flags;
	struct iattr attr;
	int opened = 0;
	int err;

	/*
	 * If no cached dentry exists or if it's negative, NFSv4 handled the
	 * opens in ->lookup() or ->create().
	 *
	 * We only get this far for a cached positive dentry.  We skipped
	 * revalidation, so handle it here by dropping the dentry and returning
	 * -EOPENSTALE.  The VFS will retry the lookup/create/open.
	 */

	dprintk("NFS: open file(%pd2)\n", dentry);

	if ((openflags & O_ACCMODE) == 3)
		openflags--;

	/* We can't create new files here */
	openflags &= ~(O_CREAT|O_EXCL);

	parent = dget_parent(dentry);
	dir = d_inode(parent);

	ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode);
	err = PTR_ERR(ctx);
	if (IS_ERR(ctx))
		goto out;

	attr.ia_valid = ATTR_OPEN;
	if (openflags & O_TRUNC) {
		attr.ia_valid |= ATTR_SIZE;
		attr.ia_size = 0;
		nfs_wb_all(inode);
	}

	inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, &opened);
	if (IS_ERR(inode)) {
		err = PTR_ERR(inode);
		switch (err) {
		case -EPERM:
		case -EACCES:
		case -EDQUOT:
		case -ENOSPC:
		case -EROFS:
			goto out_put_ctx;
		default:
			goto out_drop;
		}
	}
	if (inode != d_inode(dentry))
		goto out_drop;

	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
	nfs_file_set_open_context(filp, ctx);
	nfs_fscache_open_file(inode, filp);
	err = 0;

out_put_ctx:
	put_nfs_open_context(ctx);
out:
	dput(parent);
	return err;

out_drop:
	d_drop(dentry);
	err = -EOPENSTALE;
	goto out_put_ctx;
}

static int
nfs4_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
{
	int ret;
	struct inode *inode = file_inode(file);

	do {
		ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
		if (ret != 0)
			break;
		mutex_lock(&inode->i_mutex);
		ret = nfs_file_fsync_commit(file, start, end, datasync);
		if (!ret)
			ret = pnfs_layoutcommit_inode(inode, true);
		mutex_unlock(&inode->i_mutex);
		/*
		 * If nfs_file_fsync_commit detected a server reboot, then
		 * resend all dirty pages that might have been covered by
		 * the NFS_CONTEXT_RESEND_WRITES flag
		 */
		start = 0;
		end = LLONG_MAX;
	} while (ret == -EAGAIN);

	return ret;
}

#ifdef CONFIG_NFS_V4_2
static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence)
{
	loff_t ret;

	switch (whence) {
	case SEEK_HOLE:
	case SEEK_DATA:
		ret = nfs42_proc_llseek(filep, offset, whence);
		if (ret != -ENOTSUPP)
			return ret;
	default:
		return nfs_file_llseek(filep, offset, whence);
	}
}

static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t len)
{
	struct inode *inode = file_inode(filep);
	long ret;

	if (!S_ISREG(inode->i_mode))
		return -EOPNOTSUPP;

	if ((mode != 0) && (mode != (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE)))
		return -EOPNOTSUPP;

	ret = inode_newsize_ok(inode, offset + len);
	if (ret < 0)
		return ret;

	mutex_lock(&inode->i_mutex);
	if (mode & FALLOC_FL_PUNCH_HOLE)
		ret = nfs42_proc_deallocate(filep, offset, len);
	else
		ret = nfs42_proc_allocate(filep, offset, len);
	mutex_unlock(&inode->i_mutex);

	nfs_zap_caches(inode);
	return ret;
}
#endif /* CONFIG_NFS_V4_2 */

const struct file_operations nfs4_file_operations = {
#ifdef CONFIG_NFS_V4_2
	.llseek		= nfs4_file_llseek,
#else
	.llseek		= nfs_file_llseek,
#endif
	.read_iter	= nfs_file_read,
	.write_iter	= nfs_file_write,
	.mmap		= nfs_file_mmap,
	.open		= nfs4_file_open,
	.flush		= nfs_file_flush,
	.release	= nfs_file_release,
	.fsync		= nfs4_file_fsync,
	.lock		= nfs_lock,
	.flock		= nfs_flock,
	.splice_read	= nfs_file_splice_read,
	.splice_write	= iter_file_splice_write,
#ifdef CONFIG_NFS_V4_2
	.fallocate	= nfs42_fallocate,
#endif /* CONFIG_NFS_V4_2 */
	.check_flags	= nfs_check_flags,
	.setlease	= simple_nosetlease,
};