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-rw-r--r--fs/anon_inodes.c68
1 files changed, 51 insertions, 17 deletions
diff --git a/fs/anon_inodes.c b/fs/anon_inodes.c
index 47d4a01c5393..d11c51fc2a3f 100644
--- a/fs/anon_inodes.c
+++ b/fs/anon_inodes.c
@@ -77,28 +77,24 @@ static const struct address_space_operations anon_aops = {
77 * 77 *
78 * Creates a new file by hooking it on a single inode. This is useful for files 78 * Creates a new file by hooking it on a single inode. This is useful for files
79 * that do not need to have a full-fledged inode in order to operate correctly. 79 * that do not need to have a full-fledged inode in order to operate correctly.
80 * All the files created with anon_inode_getfd() will share a single inode, 80 * All the files created with anon_inode_getfile() will share a single inode,
81 * hence saving memory and avoiding code duplication for the file/inode/dentry 81 * hence saving memory and avoiding code duplication for the file/inode/dentry
82 * setup. Returns new descriptor or -error. 82 * setup. Returns the newly created file* or an error pointer.
83 */ 83 */
84int anon_inode_getfd(const char *name, const struct file_operations *fops, 84struct file *anon_inode_getfile(const char *name,
85 void *priv, int flags) 85 const struct file_operations *fops,
86 void *priv, int flags)
86{ 87{
87 struct qstr this; 88 struct qstr this;
88 struct dentry *dentry; 89 struct dentry *dentry;
89 struct file *file; 90 struct file *file;
90 int error, fd; 91 int error;
91 92
92 if (IS_ERR(anon_inode_inode)) 93 if (IS_ERR(anon_inode_inode))
93 return -ENODEV; 94 return ERR_PTR(-ENODEV);
94 95
95 if (fops->owner && !try_module_get(fops->owner)) 96 if (fops->owner && !try_module_get(fops->owner))
96 return -ENOENT; 97 return ERR_PTR(-ENOENT);
97
98 error = get_unused_fd_flags(flags);
99 if (error < 0)
100 goto err_module;
101 fd = error;
102 98
103 /* 99 /*
104 * Link the inode to a directory entry by creating a unique name 100 * Link the inode to a directory entry by creating a unique name
@@ -110,7 +106,7 @@ int anon_inode_getfd(const char *name, const struct file_operations *fops,
110 this.hash = 0; 106 this.hash = 0;
111 dentry = d_alloc(anon_inode_mnt->mnt_sb->s_root, &this); 107 dentry = d_alloc(anon_inode_mnt->mnt_sb->s_root, &this);
112 if (!dentry) 108 if (!dentry)
113 goto err_put_unused_fd; 109 goto err_module;
114 110
115 /* 111 /*
116 * We know the anon_inode inode count is always greater than zero, 112 * We know the anon_inode inode count is always greater than zero,
@@ -136,16 +132,54 @@ int anon_inode_getfd(const char *name, const struct file_operations *fops,
136 file->f_version = 0; 132 file->f_version = 0;
137 file->private_data = priv; 133 file->private_data = priv;
138 134
135 return file;
136
137err_dput:
138 dput(dentry);
139err_module:
140 module_put(fops->owner);
141 return ERR_PTR(error);
142}
143EXPORT_SYMBOL_GPL(anon_inode_getfile);
144
145/**
146 * anon_inode_getfd - creates a new file instance by hooking it up to an
147 * anonymous inode, and a dentry that describe the "class"
148 * of the file
149 *
150 * @name: [in] name of the "class" of the new file
151 * @fops: [in] file operations for the new file
152 * @priv: [in] private data for the new file (will be file's private_data)
153 * @flags: [in] flags
154 *
155 * Creates a new file by hooking it on a single inode. This is useful for files
156 * that do not need to have a full-fledged inode in order to operate correctly.
157 * All the files created with anon_inode_getfd() will share a single inode,
158 * hence saving memory and avoiding code duplication for the file/inode/dentry
159 * setup. Returns new descriptor or an error code.
160 */
161int anon_inode_getfd(const char *name, const struct file_operations *fops,
162 void *priv, int flags)
163{
164 int error, fd;
165 struct file *file;
166
167 error = get_unused_fd_flags(flags);
168 if (error < 0)
169 return error;
170 fd = error;
171
172 file = anon_inode_getfile(name, fops, priv, flags);
173 if (IS_ERR(file)) {
174 error = PTR_ERR(file);
175 goto err_put_unused_fd;
176 }
139 fd_install(fd, file); 177 fd_install(fd, file);
140 178
141 return fd; 179 return fd;
142 180
143err_dput:
144 dput(dentry);
145err_put_unused_fd: 181err_put_unused_fd:
146 put_unused_fd(fd); 182 put_unused_fd(fd);
147err_module:
148 module_put(fops->owner);
149 return error; 183 return error;
150} 184}
151EXPORT_SYMBOL_GPL(anon_inode_getfd); 185EXPORT_SYMBOL_GPL(anon_inode_getfd);