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-rw-r--r--fs/anon_inodes.c114
1 files changed, 1 insertions, 113 deletions
diff --git a/fs/anon_inodes.c b/fs/anon_inodes.c
index 85c961849953..24084732b1d0 100644
--- a/fs/anon_inodes.c
+++ b/fs/anon_inodes.c
@@ -24,7 +24,6 @@
24 24
25static struct vfsmount *anon_inode_mnt __read_mostly; 25static struct vfsmount *anon_inode_mnt __read_mostly;
26static struct inode *anon_inode_inode; 26static struct inode *anon_inode_inode;
27static const struct file_operations anon_inode_fops;
28 27
29/* 28/*
30 * anon_inodefs_dname() is called from d_path(). 29 * anon_inodefs_dname() is called from d_path().
@@ -39,51 +38,6 @@ static const struct dentry_operations anon_inodefs_dentry_operations = {
39 .d_dname = anon_inodefs_dname, 38 .d_dname = anon_inodefs_dname,
40}; 39};
41 40
42/*
43 * nop .set_page_dirty method so that people can use .page_mkwrite on
44 * anon inodes.
45 */
46static int anon_set_page_dirty(struct page *page)
47{
48 return 0;
49};
50
51static const struct address_space_operations anon_aops = {
52 .set_page_dirty = anon_set_page_dirty,
53};
54
55/*
56 * A single inode exists for all anon_inode files. Contrary to pipes,
57 * anon_inode inodes have no associated per-instance data, so we need
58 * only allocate one of them.
59 */
60static struct inode *anon_inode_mkinode(struct super_block *s)
61{
62 struct inode *inode = new_inode_pseudo(s);
63
64 if (!inode)
65 return ERR_PTR(-ENOMEM);
66
67 inode->i_ino = get_next_ino();
68 inode->i_fop = &anon_inode_fops;
69
70 inode->i_mapping->a_ops = &anon_aops;
71
72 /*
73 * Mark the inode dirty from the very beginning,
74 * that way it will never be moved to the dirty
75 * list because mark_inode_dirty() will think
76 * that it already _is_ on the dirty list.
77 */
78 inode->i_state = I_DIRTY;
79 inode->i_mode = S_IRUSR | S_IWUSR;
80 inode->i_uid = current_fsuid();
81 inode->i_gid = current_fsgid();
82 inode->i_flags |= S_PRIVATE;
83 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
84 return inode;
85}
86
87static struct dentry *anon_inodefs_mount(struct file_system_type *fs_type, 41static struct dentry *anon_inodefs_mount(struct file_system_type *fs_type,
88 int flags, const char *dev_name, void *data) 42 int flags, const char *dev_name, void *data)
89{ 43{
@@ -92,7 +46,7 @@ static struct dentry *anon_inodefs_mount(struct file_system_type *fs_type,
92 &anon_inodefs_dentry_operations, ANON_INODE_FS_MAGIC); 46 &anon_inodefs_dentry_operations, ANON_INODE_FS_MAGIC);
93 if (!IS_ERR(root)) { 47 if (!IS_ERR(root)) {
94 struct super_block *s = root->d_sb; 48 struct super_block *s = root->d_sb;
95 anon_inode_inode = anon_inode_mkinode(s); 49 anon_inode_inode = alloc_anon_inode(s);
96 if (IS_ERR(anon_inode_inode)) { 50 if (IS_ERR(anon_inode_inode)) {
97 dput(root); 51 dput(root);
98 deactivate_locked_super(s); 52 deactivate_locked_super(s);
@@ -109,72 +63,6 @@ static struct file_system_type anon_inode_fs_type = {
109}; 63};
110 64
111/** 65/**
112 * anon_inode_getfile_private - creates a new file instance by hooking it up to an
113 * anonymous inode, and a dentry that describe the "class"
114 * of the file
115 *
116 * @name: [in] name of the "class" of the new file
117 * @fops: [in] file operations for the new file
118 * @priv: [in] private data for the new file (will be file's private_data)
119 * @flags: [in] flags
120 *
121 *
122 * Similar to anon_inode_getfile, but each file holds a single inode.
123 *
124 */
125struct file *anon_inode_getfile_private(const char *name,
126 const struct file_operations *fops,
127 void *priv, int flags)
128{
129 struct qstr this;
130 struct path path;
131 struct file *file;
132 struct inode *inode;
133
134 if (fops->owner && !try_module_get(fops->owner))
135 return ERR_PTR(-ENOENT);
136
137 inode = anon_inode_mkinode(anon_inode_mnt->mnt_sb);
138 if (IS_ERR(inode)) {
139 file = ERR_PTR(-ENOMEM);
140 goto err_module;
141 }
142
143 /*
144 * Link the inode to a directory entry by creating a unique name
145 * using the inode sequence number.
146 */
147 file = ERR_PTR(-ENOMEM);
148 this.name = name;
149 this.len = strlen(name);
150 this.hash = 0;
151 path.dentry = d_alloc_pseudo(anon_inode_mnt->mnt_sb, &this);
152 if (!path.dentry)
153 goto err_module;
154
155 path.mnt = mntget(anon_inode_mnt);
156
157 d_instantiate(path.dentry, inode);
158
159 file = alloc_file(&path, OPEN_FMODE(flags), fops);
160 if (IS_ERR(file))
161 goto err_dput;
162
163 file->f_mapping = inode->i_mapping;
164 file->f_flags = flags & (O_ACCMODE | O_NONBLOCK);
165 file->private_data = priv;
166
167 return file;
168
169err_dput:
170 path_put(&path);
171err_module:
172 module_put(fops->owner);
173 return file;
174}
175EXPORT_SYMBOL_GPL(anon_inode_getfile_private);
176
177/**
178 * anon_inode_getfile - creates a new file instance by hooking it up to an 66 * anon_inode_getfile - creates a new file instance by hooking it up to an
179 * anonymous inode, and a dentry that describe the "class" 67 * anonymous inode, and a dentry that describe the "class"
180 * of the file 68 * of the file