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Subject[PATCH 1/7] Add a new flags-accepting interface for anonymous inodes
From
Add functions forwarding from the old names to the new ones so we
don't need to change any callers.

Signed-off-by: Daniel Colascione <dancol@google.com>
---
fs/anon_inodes.c | 62 ++++++++++++++++++++++---------------
include/linux/anon_inodes.h | 27 +++++++++++++---
2 files changed, 59 insertions(+), 30 deletions(-)

diff --git a/fs/anon_inodes.c b/fs/anon_inodes.c
index 89714308c25b..caa36019afca 100644
--- a/fs/anon_inodes.c
+++ b/fs/anon_inodes.c
@@ -56,60 +56,71 @@ static struct file_system_type anon_inode_fs_type = {
};

/**
- * anon_inode_getfile - creates a new file instance by hooking it up to an
- * anonymous inode, and a dentry that describe the "class"
- * of the file
+ * anon_inode_getfile2 - creates a new file instance by hooking it up to
+ * an anonymous inode, and a dentry that describe
+ * the "class" of the file
*
* @name: [in] name of the "class" of the new file
* @fops: [in] file operations for the new file
* @priv: [in] private data for the new file (will be file's private_data)
- * @flags: [in] flags
+ * @flags: [in] flags for the file
+ * @anon_inode_flags: [in] flags for anon_inode*
*
- * Creates a new file by hooking it on a single inode. This is useful for files
+ * Creates a new file by hooking it on an unspecified inode. This is useful for files
* that do not need to have a full-fledged inode in order to operate correctly.
* All the files created with anon_inode_getfile() will share a single inode,
* hence saving memory and avoiding code duplication for the file/inode/dentry
* setup. Returns the newly created file* or an error pointer.
+ *
+ * anon_inode_flags must be zero.
*/
-struct file *anon_inode_getfile(const char *name,
- const struct file_operations *fops,
- void *priv, int flags)
+struct file *anon_inode_getfile2(const char *name,
+ const struct file_operations *fops,
+ void *priv, int flags, int anon_inode_flags)
{
+ struct inode *inode;
struct file *file;

- if (IS_ERR(anon_inode_inode))
- return ERR_PTR(-ENODEV);
-
- if (fops->owner && !try_module_get(fops->owner))
- return ERR_PTR(-ENOENT);
+ if (anon_inode_flags)
+ return ERR_PTR(-EINVAL);

+ inode = anon_inode_inode;
+ if (IS_ERR(inode))
+ return ERR_PTR(-ENODEV);
/*
- * We know the anon_inode inode count is always greater than zero,
- * so ihold() is safe.
+ * We know the anon_inode inode count is always
+ * greater than zero, so ihold() is safe.
*/
- ihold(anon_inode_inode);
- file = alloc_file_pseudo(anon_inode_inode, anon_inode_mnt, name,
+ ihold(inode);
+
+ if (fops->owner && !try_module_get(fops->owner)) {
+ file = ERR_PTR(-ENOENT);
+ goto err;
+ }
+
+ file = alloc_file_pseudo(inode, anon_inode_mnt, name,
flags & (O_ACCMODE | O_NONBLOCK), fops);
if (IS_ERR(file))
goto err;

- file->f_mapping = anon_inode_inode->i_mapping;
+ file->f_mapping = inode->i_mapping;

file->private_data = priv;

return file;

err:
- iput(anon_inode_inode);
+ iput(inode);
module_put(fops->owner);
return file;
}
EXPORT_SYMBOL_GPL(anon_inode_getfile);
+EXPORT_SYMBOL_GPL(anon_inode_getfile2);

/**
- * anon_inode_getfd - creates a new file instance by hooking it up to an
- * anonymous inode, and a dentry that describe the "class"
- * of the file
+ * anon_inode_getfd2 - creates a new file instance by hooking it up to an
+ * anonymous inode, and a dentry that describe the "class"
+ * of the file
*
* @name: [in] name of the "class" of the new file
* @fops: [in] file operations for the new file
@@ -122,8 +133,8 @@ EXPORT_SYMBOL_GPL(anon_inode_getfile);
* hence saving memory and avoiding code duplication for the file/inode/dentry
* setup. Returns new descriptor or an error code.
*/
-int anon_inode_getfd(const char *name, const struct file_operations *fops,
- void *priv, int flags)
+int anon_inode_getfd2(const char *name, const struct file_operations *fops,
+ void *priv, int flags, int anon_inode_flags)
{
int error, fd;
struct file *file;
@@ -133,7 +144,7 @@ int anon_inode_getfd(const char *name, const struct file_operations *fops,
return error;
fd = error;

- file = anon_inode_getfile(name, fops, priv, flags);
+ file = anon_inode_getfile2(name, fops, priv, flags, anon_inode_flags);
if (IS_ERR(file)) {
error = PTR_ERR(file);
goto err_put_unused_fd;
@@ -147,6 +158,7 @@ int anon_inode_getfd(const char *name, const struct file_operations *fops,
return error;
}
EXPORT_SYMBOL_GPL(anon_inode_getfd);
+EXPORT_SYMBOL_GPL(anon_inode_getfd2);

static int __init anon_inode_init(void)
{
diff --git a/include/linux/anon_inodes.h b/include/linux/anon_inodes.h
index d0d7d96261ad..10699462dcb1 100644
--- a/include/linux/anon_inodes.h
+++ b/include/linux/anon_inodes.h
@@ -11,11 +11,28 @@

struct file_operations;

-struct file *anon_inode_getfile(const char *name,
- const struct file_operations *fops,
- void *priv, int flags);
-int anon_inode_getfd(const char *name, const struct file_operations *fops,
- void *priv, int flags);
+#define ANON_INODE_SECURE 1
+
+struct file *anon_inode_getfile2(const char *name,
+ const struct file_operations *fops,
+ void *priv, int flags, int anon_inode_flags);
+int anon_inode_getfd2(const char *name, const struct file_operations *fops,
+ void *priv, int flags, int anon_inode_flags);
+
+static inline int anon_inode_getfd(const char *name,
+ const struct file_operations *fops,
+ void *priv, int flags)
+{
+ return anon_inode_getfd2(name, fops, priv, flags, 0);
+}
+
+static inline struct file *anon_inode_getfile(const char *name,
+ const struct file_operations *fops,
+ void *priv, int flags)
+{
+ return anon_inode_getfile2(name, fops, priv, flags, 0);
+}
+

#endif /* _LINUX_ANON_INODES_H */

--
2.23.0.700.g56cf767bdb-goog
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