From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Colascione Subject: [PATCH 1/7] Add a new flags-accepting interface for anonymous inodes Date: Sat, 12 Oct 2019 12:15:56 -0700 Message-ID: <20191012191602.45649-2-dancol@google.com> References: <20191012191602.45649-1-dancol@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <20191012191602.45649-1-dancol@google.com> Sender: linux-kernel-owner@vger.kernel.org To: linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, lokeshgidra@google.com, dancol@google.com, nnk@google.com Cc: nosh@google.com, timmurray@google.com List-Id: linux-api@vger.kernel.org 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 --- 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