aboutsummaryrefslogtreecommitdiff
path: root/fs/nfs/nfs4file.c
blob: e7699308364acf6f84fcf62e5f815ed2c74c2b5c (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
/*
 *  linux/fs/nfs/file.c
 *
 *  Copyright (C) 1992  Rick Sladkey
 */
#include <linux/nfs_fs.h>
#include "internal.h"
#include "pnfs.h"

#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 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(%s/%s)\n",
		dentry->d_parent->d_name.name,
		dentry->d_name.name);

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

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

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

	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);
	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;
		}
	}
	iput(inode);
	if (inode != dentry->d_inode)
		goto out_drop;

	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
	nfs_file_set_open_context(filp, ctx);
	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->f_path.dentry->d_inode;

	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 && !datasync)
			/* application has asked for meta-data sync */
			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;
}

const struct file_operations nfs4_file_operations = {
	.llseek		= nfs_file_llseek,
	.read		= do_sync_read,
	.write		= do_sync_write,
	.aio_read	= nfs_file_read,
	.aio_write	= 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	= nfs_file_splice_write,
	.check_flags	= nfs_check_flags,
	.setlease	= nfs_setlease,
};