summaryrefslogtreecommitdiff
path: root/fs/nfs/nfs4file.c
blob: 96db471ca2e5c5413edf5ffe120097cb88d079ee (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
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
// SPDX-License-Identifier: GPL-2.0
/*
 *  linux/fs/nfs/file.c
 *
 *  Copyright (C) 1992  Rick Sladkey
 */
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/falloc.h>
#include <linux/nfs_fs.h>
#include "delegation.h"
#include "internal.h"
#include "iostat.h"
#include "fscache.h"
#include "pnfs.h"

#include "nfstrace.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 = file_dentry(filp);
	struct dentry *parent = NULL;
	struct inode *dir;
	unsigned openflags = filp->f_flags;
	struct iattr attr;
	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);

	err = nfs_check_flags(openflags);
	if (err)
		return err;

	if ((openflags & O_ACCMODE) == 3)
		return nfs_open(inode, filp);

	/* 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(file_dentry(filp), filp->f_mode, filp);
	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;
		filemap_write_and_wait(inode->i_mapping);
	}

	inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, NULL);
	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;
}

/*
 * Flush all dirty pages, and check for write errors.
 */
static int
nfs4_file_flush(struct file *file, fl_owner_t id)
{
	struct inode	*inode = file_inode(file);

	dprintk("NFS: flush(%pD2)\n", file);

	nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
	if ((file->f_mode & FMODE_WRITE) == 0)
		return 0;

	/*
	 * If we're holding a write delegation, then check if we're required
	 * to flush the i/o on close. If not, then just start the i/o now.
	 */
	if (!nfs4_delegation_flush_on_close(inode))
		return filemap_fdatawrite(file->f_mapping);

	/* Flush writes to the server and return any errors */
	return nfs_wb_all(inode);
}

#ifdef CONFIG_NFS_V4_2
static ssize_t __nfs4_copy_file_range(struct file *file_in, loff_t pos_in,
				      struct file *file_out, loff_t pos_out,
				      size_t count, unsigned int flags)
{
	/* Only offload copy if superblock is the same */
	if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb)
		return -EXDEV;
	if (!nfs_server_capable(file_inode(file_out), NFS_CAP_COPY))
		return -EOPNOTSUPP;
	if (file_inode(file_in) == file_inode(file_out))
		return -EOPNOTSUPP;
	return nfs42_proc_copy(file_in, pos_in, file_out, pos_out, count);
}

static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in,
				    struct file *file_out, loff_t pos_out,
				    size_t count, unsigned int flags)
{
	ssize_t ret;

	ret = __nfs4_copy_file_range(file_in, pos_in, file_out, pos_out, count,
				     flags);
	if (ret == -EOPNOTSUPP || ret == -EXDEV)
		ret = generic_copy_file_range(file_in, pos_in, file_out,
					      pos_out, count, flags);
	return ret;
}

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;
		/* Fall through */
	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;

	if (mode & FALLOC_FL_PUNCH_HOLE)
		return nfs42_proc_deallocate(filep, offset, len);
	return nfs42_proc_allocate(filep, offset, len);
}

static loff_t nfs42_remap_file_range(struct file *src_file, loff_t src_off,
		struct file *dst_file, loff_t dst_off, loff_t count,
		unsigned int remap_flags)
{
	struct inode *dst_inode = file_inode(dst_file);
	struct nfs_server *server = NFS_SERVER(dst_inode);
	struct inode *src_inode = file_inode(src_file);
	unsigned int bs = server->clone_blksize;
	bool same_inode = false;
	int ret;

	/* NFS does not support deduplication. */
	if (remap_flags & REMAP_FILE_DEDUP)
		return -EOPNOTSUPP;

	if (remap_flags & ~REMAP_FILE_ADVISORY)
		return -EINVAL;

	/* check alignment w.r.t. clone_blksize */
	ret = -EINVAL;
	if (bs) {
		if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs))
			goto out;
		if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count))
			goto out;
	}

	if (src_inode == dst_inode)
		same_inode = true;

	/* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */
	if (same_inode) {
		inode_lock(src_inode);
	} else if (dst_inode < src_inode) {
		inode_lock_nested(dst_inode, I_MUTEX_PARENT);
		inode_lock_nested(src_inode, I_MUTEX_CHILD);
	} else {
		inode_lock_nested(src_inode, I_MUTEX_PARENT);
		inode_lock_nested(dst_inode, I_MUTEX_CHILD);
	}

	/* flush all pending writes on both src and dst so that server
	 * has the latest data */
	ret = nfs_sync_inode(src_inode);
	if (ret)
		goto out_unlock;
	ret = nfs_sync_inode(dst_inode);
	if (ret)
		goto out_unlock;

	ret = nfs42_proc_clone(src_file, dst_file, src_off, dst_off, count);

	/* truncate inode page cache of the dst range so that future reads can fetch
	 * new data from server */
	if (!ret)
		truncate_inode_pages_range(&dst_inode->i_data, dst_off, dst_off + count - 1);

out_unlock:
	if (same_inode) {
		inode_unlock(src_inode);
	} else if (dst_inode < src_inode) {
		inode_unlock(src_inode);
		inode_unlock(dst_inode);
	} else {
		inode_unlock(dst_inode);
		inode_unlock(src_inode);
	}
out:
	return ret < 0 ? ret : count;
}
#endif /* CONFIG_NFS_V4_2 */

const struct file_operations nfs4_file_operations = {
	.read_iter	= nfs_file_read,
	.write_iter	= nfs_file_write,
	.mmap		= nfs_file_mmap,
	.open		= nfs4_file_open,
	.flush		= nfs4_file_flush,
	.release	= nfs_file_release,
	.fsync		= nfs_file_fsync,
	.lock		= nfs_lock,
	.flock		= nfs_flock,
	.splice_read	= generic_file_splice_read,
	.splice_write	= iter_file_splice_write,
	.check_flags	= nfs_check_flags,
	.setlease	= simple_nosetlease,
#ifdef CONFIG_NFS_V4_2
	.copy_file_range = nfs4_copy_file_range,
	.llseek		= nfs4_file_llseek,
	.fallocate	= nfs42_fallocate,
	.remap_file_range = nfs42_remap_file_range,
#else
	.llseek		= nfs_file_llseek,
#endif
};