From: Muchun Song <songmuchun@xxxxxxxxxxxxx> Subject: fs: proc: store PDE()->data into inode->i_private PDE_DATA(inode) is introduced to get user private data and hide the layout of struct proc_dir_entry. The inode->i_private is used to do the same thing as well. Save a copy of user private data to inode-> i_private when proc inode is allocated. This means the user also can get their private data by inode->i_private. Introduce pde_data() to wrap inode->i_private so that we can remove PDE_DATA() from fs/proc/generic.c and make PTE_DATE() as a wrapper of pde_data(). It will be easier if we decide to remove PDE_DATE() in the future. Link: https://lkml.kernel.org/r/20211124081956.87711-1-songmuchun@xxxxxxxxxxxxx Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx> Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx> Cc: Alexey Gladkov <gladkov.alexey@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/proc/generic.c | 6 ------ fs/proc/inode.c | 1 + fs/proc/internal.h | 5 ----- include/linux/proc_fs.h | 13 ++++++++++++- 4 files changed, 13 insertions(+), 12 deletions(-) --- a/fs/proc/generic.c~fs-proc-store-pde-data-into-inode-i_private +++ a/fs/proc/generic.c @@ -791,12 +791,6 @@ void proc_remove(struct proc_dir_entry * } EXPORT_SYMBOL(proc_remove); -void *PDE_DATA(const struct inode *inode) -{ - return __PDE_DATA(inode); -} -EXPORT_SYMBOL(PDE_DATA); - /* * Pull a user buffer into memory and pass it to the file's write handler if * one is supplied. The ->write() method is permitted to modify the --- a/fs/proc/inode.c~fs-proc-store-pde-data-into-inode-i_private +++ a/fs/proc/inode.c @@ -650,6 +650,7 @@ struct inode *proc_get_inode(struct supe return NULL; } + inode->i_private = de->data; inode->i_ino = de->low_ino; inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); PROC_I(inode)->pde = de; --- a/fs/proc/internal.h~fs-proc-store-pde-data-into-inode-i_private +++ a/fs/proc/internal.h @@ -115,11 +115,6 @@ static inline struct proc_dir_entry *PDE return PROC_I(inode)->pde; } -static inline void *__PDE_DATA(const struct inode *inode) -{ - return PDE(inode)->data; -} - static inline struct pid *proc_pid(const struct inode *inode) { return PROC_I(inode)->pid; --- a/include/linux/proc_fs.h~fs-proc-store-pde-data-into-inode-i_private +++ a/include/linux/proc_fs.h @@ -110,7 +110,18 @@ extern struct proc_dir_entry *proc_creat struct proc_dir_entry *proc_create(const char *name, umode_t mode, struct proc_dir_entry *parent, const struct proc_ops *proc_ops); extern void proc_set_size(struct proc_dir_entry *, loff_t); extern void proc_set_user(struct proc_dir_entry *, kuid_t, kgid_t); -extern void *PDE_DATA(const struct inode *); + +/* + * Obtain the private data passed by user through proc_create_data() or + * related. + */ +static inline void *pde_data(const struct inode *inode) +{ + return inode->i_private; +} + +#define PDE_DATA(i) pde_data(i) + extern void *proc_get_parent_data(const struct inode *); extern void proc_remove(struct proc_dir_entry *); extern void remove_proc_entry(const char *, struct proc_dir_entry *); _