[linux-2.6-block.git] / fs / proc / internal.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/* Internal procfs definitions
 *
 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#include <linux/proc_fs.h>
#include <linux/proc_ns.h>
#include <linux/refcount.h>
#include <linux/spinlock.h>
#include <linux/atomic.h>
#include <linux/binfmts.h>
#include <linux/sched/coredump.h>
#include <linux/sched/task.h>
#include <linux/mm.h>

struct ctl_table_header;
struct mempolicy;

/*
 * This is not completely implemented yet. The idea is to
 * create an in-memory tree (like the actual /proc filesystem
 * tree) of these proc_dir_entries, so that we can dynamically
 * add new files to /proc.
 *
 * parent/subdir are used for the directory structure (every /proc file has a
 * parent, but "subdir" is empty for all non-directory entries).
 * subdir_node is used to build the rb tree "subdir" of the parent.
 */
struct proc_dir_entry {
	/*
	 * number of callers into module in progress;
	 * negative -> it's going away RSN
	 */
	atomic_t in_use;
	refcount_t refcnt;
	struct list_head pde_openers;	/* who did ->open, but not ->release */
	/* protects ->pde_openers and all struct pde_opener instances */
	spinlock_t pde_unload_lock;
	struct completion *pde_unload_completion;
	const struct inode_operations *proc_iops;
	union {
		const struct proc_ops *proc_ops;
		const struct file_operations *proc_dir_ops;
	};
	const struct dentry_operations *proc_dops;
	union {
		const struct seq_operations *seq_ops;
		int (*single_show)(struct seq_file *, void *);
	};
	proc_write_t write;
	void *data;
	unsigned int state_size;
	unsigned int low_ino;
	nlink_t nlink;
	kuid_t uid;
	kgid_t gid;
	loff_t size;
	struct proc_dir_entry *parent;
	struct rb_root subdir;
	struct rb_node subdir_node;
	char *name;
	umode_t mode;
	u8 flags;
	u8 namelen;
	char inline_name[];
} __randomize_layout;

#define SIZEOF_PDE	(				\
	sizeof(struct proc_dir_entry) < 128 ? 128 :	\
	sizeof(struct proc_dir_entry) < 192 ? 192 :	\
	sizeof(struct proc_dir_entry) < 256 ? 256 :	\
	sizeof(struct proc_dir_entry) < 512 ? 512 :	\
	0)
#define SIZEOF_PDE_INLINE_NAME (SIZEOF_PDE - sizeof(struct proc_dir_entry))

static inline bool pde_is_permanent(const struct proc_dir_entry *pde)
{
	return pde->flags & PROC_ENTRY_PERMANENT;
}

static inline void pde_make_permanent(struct proc_dir_entry *pde)
{
	pde->flags |= PROC_ENTRY_PERMANENT;
}

static inline bool pde_has_proc_read_iter(const struct proc_dir_entry *pde)
{
	return pde->flags & PROC_ENTRY_proc_read_iter;
}

static inline bool pde_has_proc_compat_ioctl(const struct proc_dir_entry *pde)
{
#ifdef CONFIG_COMPAT
	return pde->flags & PROC_ENTRY_proc_compat_ioctl;
#else
	return false;
#endif
}

extern struct kmem_cache *proc_dir_entry_cache;
void pde_free(struct proc_dir_entry *pde);

union proc_op {
	int (*proc_get_link)(struct dentry *, struct path *);
	int (*proc_show)(struct seq_file *m,
		struct pid_namespace *ns, struct pid *pid,
		struct task_struct *task);
	int lsmid;
};

struct proc_inode {
	struct pid *pid;
	unsigned int fd;
	union proc_op op;
	struct proc_dir_entry *pde;
	struct ctl_table_header *sysctl;
	const struct ctl_table *sysctl_entry;
	struct hlist_node sibling_inodes;
	const struct proc_ns_operations *ns_ops;
	struct inode vfs_inode;
} __randomize_layout;

/*
 * General functions
 */
static inline struct proc_inode *PROC_I(const struct inode *inode)
{
	return container_of(inode, struct proc_inode, vfs_inode);
}

static inline struct proc_dir_entry *PDE(const struct inode *inode)
{
	return PROC_I(inode)->pde;
}

static inline struct pid *proc_pid(const struct inode *inode)
{
	return PROC_I(inode)->pid;
}

static inline struct task_struct *get_proc_task(const struct inode *inode)
{
	return get_pid_task(proc_pid(inode), PIDTYPE_PID);
}

void task_dump_owner(struct task_struct *task, umode_t mode,
		     kuid_t *ruid, kgid_t *rgid);

unsigned name_to_int(const struct qstr *qstr);
/*
 * Offset of the first process in the /proc root directory..
 */
#define FIRST_PROCESS_ENTRY 256

/* Worst case buffer size needed for holding an integer. */
#define PROC_NUMBUF 13

#ifdef CONFIG_PAGE_MAPCOUNT
/**
 * folio_precise_page_mapcount() - Number of mappings of this folio page.
 * @folio: The folio.
 * @page: The page.
 *
 * The number of present user page table entries that reference this page
 * as tracked via the RMAP: either referenced directly (PTE) or as part of
 * a larger area that covers this page (e.g., PMD).
 *
 * Use this function only for the calculation of existing statistics
 * (USS, PSS, mapcount_max) and for debugging purposes (/proc/kpagecount).
 *
 * Do not add new users.
 *
 * Returns: The number of mappings of this folio page. 0 for
 * folios that are not mapped to user space or are not tracked via the RMAP
 * (e.g., shared zeropage).
 */
static inline int folio_precise_page_mapcount(struct folio *folio,
		struct page *page)
{
	int mapcount = atomic_read(&page->_mapcount) + 1;

	if (page_mapcount_is_type(mapcount))
		mapcount = 0;
	if (folio_test_large(folio))
		mapcount += folio_entire_mapcount(folio);

	return mapcount;
}
#else /* !CONFIG_PAGE_MAPCOUNT */
static inline int folio_precise_page_mapcount(struct folio *folio,
		struct page *page)
{
	BUILD_BUG();
}
#endif /* CONFIG_PAGE_MAPCOUNT */

/**
 * folio_average_page_mapcount() - Average number of mappings per page in this
 *				   folio
 * @folio: The folio.
 *
 * The average number of user page table entries that reference each page in
 * this folio as tracked via the RMAP: either referenced directly (PTE) or
 * as part of a larger area that covers this page (e.g., PMD).
 *
 * The average is calculated by rounding to the nearest integer; however,
 * to avoid duplicated code in current callers, the average is at least
 * 1 if any page of the folio is mapped.
 *
 * Returns: The average number of mappings per page in this folio.
 */
static inline int folio_average_page_mapcount(struct folio *folio)
{
	int mapcount, entire_mapcount, avg;

	if (!folio_test_large(folio))
		return atomic_read(&folio->_mapcount) + 1;

	mapcount = folio_large_mapcount(folio);
	if (unlikely(mapcount <= 0))
		return 0;
	entire_mapcount = folio_entire_mapcount(folio);
	if (mapcount <= entire_mapcount)
		return entire_mapcount;
	mapcount -= entire_mapcount;

	/* Round to closest integer ... */
	avg = ((unsigned int)mapcount + folio_large_nr_pages(folio) / 2) >> folio_large_order(folio);
	/* ... but return at least 1. */
	return max_t(int, avg + entire_mapcount, 1);
}
/*
 * array.c
 */
extern const struct file_operations proc_tid_children_operations;

extern void proc_task_name(struct seq_file *m, struct task_struct *p,
			   bool escape);
extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
			 struct pid *, struct task_struct *);
extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
			  struct pid *, struct task_struct *);
extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
			   struct pid *, struct task_struct *);
extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
			  struct pid *, struct task_struct *);

/*
 * base.c
 */
extern const struct dentry_operations pid_dentry_operations;
extern int pid_getattr(struct mnt_idmap *, const struct path *,
		       struct kstat *, u32, unsigned int);
extern int proc_setattr(struct mnt_idmap *, struct dentry *,
			struct iattr *);
extern void proc_pid_evict_inode(struct proc_inode *);
extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
extern void pid_update_inode(struct task_struct *, struct inode *);
extern int pid_delete_dentry(const struct dentry *);
extern int proc_pid_readdir(struct file *, struct dir_context *);
struct dentry *proc_pid_lookup(struct dentry *, unsigned int);
extern loff_t mem_lseek(struct file *, loff_t, int);

/* Lookups */
typedef struct dentry *instantiate_t(struct dentry *,
				     struct task_struct *, const void *);
bool proc_fill_cache(struct file *, struct dir_context *, const char *, unsigned int,
			   instantiate_t, struct task_struct *, const void *);

/*
 * generic.c
 */
struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode,
		struct proc_dir_entry **parent, void *data);
struct proc_dir_entry *proc_register(struct proc_dir_entry *dir,
		struct proc_dir_entry *dp);
extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
struct dentry *proc_lookup_de(struct inode *, struct dentry *, struct proc_dir_entry *);
extern int proc_readdir(struct file *, struct dir_context *);
int proc_readdir_de(struct file *, struct dir_context *, struct proc_dir_entry *);

static inline void pde_get(struct proc_dir_entry *pde)
{
	refcount_inc(&pde->refcnt);
}
extern void pde_put(struct proc_dir_entry *);

static inline bool is_empty_pde(const struct proc_dir_entry *pde)
{
	return S_ISDIR(pde->mode) && !pde->proc_iops;
}
extern ssize_t proc_simple_write(struct file *, const char __user *, size_t, loff_t *);

/*
 * inode.c
 */
struct pde_opener {
	struct list_head lh;
	struct file *file;
	bool closing;
	struct completion *c;
} __randomize_layout;
extern const struct inode_operations proc_link_inode_operations;
extern const struct inode_operations proc_pid_link_inode_operations;
extern const struct super_operations proc_sops;

void proc_init_kmemcache(void);
void proc_invalidate_siblings_dcache(struct hlist_head *inodes, spinlock_t *lock);
void set_proc_pid_nlink(void);
extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
extern void proc_entry_rundown(struct proc_dir_entry *);

/*
 * proc_namespaces.c
 */
extern const struct inode_operations proc_ns_dir_inode_operations;
extern const struct file_operations proc_ns_dir_operations;

/*
 * proc_net.c
 */
extern const struct file_operations proc_net_operations;
extern const struct inode_operations proc_net_inode_operations;

#ifdef CONFIG_NET
extern int proc_net_init(void);
#else
static inline int proc_net_init(void) { return 0; }
#endif

/*
 * proc_self.c
 */
extern int proc_setup_self(struct super_block *);

/*
 * proc_thread_self.c
 */
extern int proc_setup_thread_self(struct super_block *);
extern void proc_thread_self_init(void);

/*
 * proc_sysctl.c
 */
#ifdef CONFIG_PROC_SYSCTL
extern int proc_sys_init(void);
extern void proc_sys_evict_inode(struct inode *inode,
				 struct ctl_table_header *head);
#else
static inline void proc_sys_init(void) { }
static inline void proc_sys_evict_inode(struct  inode *inode,
					struct ctl_table_header *head) { }
#endif

/*
 * proc_tty.c
 */
#ifdef CONFIG_TTY
extern void proc_tty_init(void);
#else
static inline void proc_tty_init(void) {}
#endif

/*
 * root.c
 */
extern struct proc_dir_entry proc_root;

extern void proc_self_init(void);

/*
 * task_[no]mmu.c
 */
struct mem_size_stats;
struct proc_maps_private {
	struct inode *inode;
	struct task_struct *task;
	struct mm_struct *mm;
	struct vma_iterator iter;
#ifdef CONFIG_NUMA
	struct mempolicy *task_mempolicy;
#endif
} __randomize_layout;

struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);

extern const struct file_operations proc_pid_maps_operations;
extern const struct file_operations proc_pid_numa_maps_operations;
extern const struct file_operations proc_pid_smaps_operations;
extern const struct file_operations proc_pid_smaps_rollup_operations;
extern const struct file_operations proc_clear_refs_operations;
extern const struct file_operations proc_pagemap_operations;

extern unsigned long task_vsize(struct mm_struct *);
extern unsigned long task_statm(struct mm_struct *,
				unsigned long *, unsigned long *,
				unsigned long *, unsigned long *);
extern void task_mem(struct seq_file *, struct mm_struct *);

extern const struct dentry_operations proc_net_dentry_ops;
static inline void pde_force_lookup(struct proc_dir_entry *pde)
{
	/* /proc/net/ entries can be changed under us by setns(CLONE_NEWNET) */
	pde->proc_dops = &proc_net_dentry_ops;
}

/*
 * Add a new procfs dentry that can't serve as a mountpoint. That should
 * encompass anything that is ephemeral and can just disappear while the
 * process is still around.
 */
static inline struct dentry *proc_splice_unmountable(struct inode *inode,
		struct dentry *dentry, const struct dentry_operations *d_ops)
{
	d_set_d_op(dentry, d_ops);
	dont_mount(dentry);
	return d_splice_alias(inode, dentry);
}
Commit	Line	Data
	1	/* SPDX-License-Identifier: GPL-2.0-or-later */
	2	/* Internal procfs definitions
	3	*
	4	* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
	5	* Written by David Howells (dhowells@redhat.com)
	6	*/
	7
	8	#include <linux/proc_fs.h>
	9	#include <linux/proc_ns.h>
	10	#include <linux/refcount.h>
	11	#include <linux/spinlock.h>
	12	#include <linux/atomic.h>
	13	#include <linux/binfmts.h>
	14	#include <linux/sched/coredump.h>
	15	#include <linux/sched/task.h>
	16	#include <linux/mm.h>
	17
	18	struct ctl_table_header;
	19	struct mempolicy;
	20
	21	/*
	22	* This is not completely implemented yet. The idea is to
	23	* create an in-memory tree (like the actual /proc filesystem
	24	* tree) of these proc_dir_entries, so that we can dynamically
	25	* add new files to /proc.
	26	*
	27	* parent/subdir are used for the directory structure (every /proc file has a
	28	* parent, but "subdir" is empty for all non-directory entries).
	29	* subdir_node is used to build the rb tree "subdir" of the parent.
	30	*/
	31	struct proc_dir_entry {
	32	/*
	33	* number of callers into module in progress;
	34	* negative -> it's going away RSN
	35	*/
	36	atomic_t in_use;
	37	refcount_t refcnt;
	38	struct list_head pde_openers; /* who did ->open, but not ->release */
	39	/* protects ->pde_openers and all struct pde_opener instances */
	40	spinlock_t pde_unload_lock;
	41	struct completion *pde_unload_completion;
	42	const struct inode_operations *proc_iops;
	43	union {
	44	const struct proc_ops *proc_ops;
	45	const struct file_operations *proc_dir_ops;
	46	};
	47	const struct dentry_operations *proc_dops;
	48	union {
	49	const struct seq_operations *seq_ops;
	50	int (single_show)(struct seq_file , void *);
	51	};
	52	proc_write_t write;
	53	void *data;
	54	unsigned int state_size;
	55	unsigned int low_ino;
	56	nlink_t nlink;
	57	kuid_t uid;
	58	kgid_t gid;
	59	loff_t size;
	60	struct proc_dir_entry *parent;
	61	struct rb_root subdir;
	62	struct rb_node subdir_node;
	63	char *name;
	64	umode_t mode;
	65	u8 flags;
	66	u8 namelen;
	67	char inline_name[];
	68	} __randomize_layout;
	69
	70	#define SIZEOF_PDE ( \
	71	sizeof(struct proc_dir_entry) < 128 ? 128 : \
	72	sizeof(struct proc_dir_entry) < 192 ? 192 : \
	73	sizeof(struct proc_dir_entry) < 256 ? 256 : \
	74	sizeof(struct proc_dir_entry) < 512 ? 512 : \
	75	0)
	76	#define SIZEOF_PDE_INLINE_NAME (SIZEOF_PDE - sizeof(struct proc_dir_entry))
	77
	78	static inline bool pde_is_permanent(const struct proc_dir_entry *pde)
	79	{
	80	return pde->flags & PROC_ENTRY_PERMANENT;
	81	}
	82
	83	static inline void pde_make_permanent(struct proc_dir_entry *pde)
	84	{
	85	pde->flags \|= PROC_ENTRY_PERMANENT;
	86	}
	87
	88	static inline bool pde_has_proc_read_iter(const struct proc_dir_entry *pde)
	89	{
	90	return pde->flags & PROC_ENTRY_proc_read_iter;
	91	}
	92
	93	static inline bool pde_has_proc_compat_ioctl(const struct proc_dir_entry *pde)
	94	{
	95	#ifdef CONFIG_COMPAT
	96	return pde->flags & PROC_ENTRY_proc_compat_ioctl;
	97	#else
	98	return false;
	99	#endif
	100	}
	101
	102	extern struct kmem_cache *proc_dir_entry_cache;
	103	void pde_free(struct proc_dir_entry *pde);
	104
	105	union proc_op {
	106	int (proc_get_link)(struct dentry , struct path *);
	107	int (proc_show)(struct seq_file m,
	108	struct pid_namespace ns, struct pid pid,
	109	struct task_struct *task);
	110	int lsmid;
	111	};
	112
	113	struct proc_inode {
	114	struct pid *pid;
	115	unsigned int fd;
	116	union proc_op op;
	117	struct proc_dir_entry *pde;
	118	struct ctl_table_header *sysctl;
	119	const struct ctl_table *sysctl_entry;
	120	struct hlist_node sibling_inodes;
	121	const struct proc_ns_operations *ns_ops;
	122	struct inode vfs_inode;
	123	} __randomize_layout;
	124
	125	/*
	126	* General functions
	127	*/
	128	static inline struct proc_inode PROC_I(const struct inode inode)
	129	{
	130	return container_of(inode, struct proc_inode, vfs_inode);
	131	}
	132
	133	static inline struct proc_dir_entry PDE(const struct inode inode)
	134	{
	135	return PROC_I(inode)->pde;
	136	}
	137
	138	static inline struct pid proc_pid(const struct inode inode)
	139	{
	140	return PROC_I(inode)->pid;
	141	}
	142
	143	static inline struct task_struct get_proc_task(const struct inode inode)
	144	{
	145	return get_pid_task(proc_pid(inode), PIDTYPE_PID);
	146	}
	147
	148	void task_dump_owner(struct task_struct *task, umode_t mode,
	149	kuid_t ruid, kgid_t rgid);
	150
	151	unsigned name_to_int(const struct qstr *qstr);
	152	/*
	153	* Offset of the first process in the /proc root directory..
	154	*/
	155	#define FIRST_PROCESS_ENTRY 256
	156
	157	/* Worst case buffer size needed for holding an integer. */
	158	#define PROC_NUMBUF 13
	159
	160	#ifdef CONFIG_PAGE_MAPCOUNT
	161	/**
	162	* folio_precise_page_mapcount() - Number of mappings of this folio page.
	163	* @folio: The folio.
	164	* @page: The page.
	165	*
	166	* The number of present user page table entries that reference this page
	167	* as tracked via the RMAP: either referenced directly (PTE) or as part of
	168	* a larger area that covers this page (e.g., PMD).
	169	*
	170	* Use this function only for the calculation of existing statistics
	171	* (USS, PSS, mapcount_max) and for debugging purposes (/proc/kpagecount).
	172	*
	173	* Do not add new users.
	174	*
	175	* Returns: The number of mappings of this folio page. 0 for
	176	* folios that are not mapped to user space or are not tracked via the RMAP
	177	* (e.g., shared zeropage).
	178	*/
	179	static inline int folio_precise_page_mapcount(struct folio *folio,
	180	struct page *page)
	181	{
	182	int mapcount = atomic_read(&page->_mapcount) + 1;
	183
	184	if (page_mapcount_is_type(mapcount))
	185	mapcount = 0;
	186	if (folio_test_large(folio))
	187	mapcount += folio_entire_mapcount(folio);
	188
	189	return mapcount;
	190	}
	191	#else /* !CONFIG_PAGE_MAPCOUNT */
	192	static inline int folio_precise_page_mapcount(struct folio *folio,
	193	struct page *page)
	194	{
	195	BUILD_BUG();
	196	}
	197	#endif /* CONFIG_PAGE_MAPCOUNT */
	198
	199	/**
	200	* folio_average_page_mapcount() - Average number of mappings per page in this
	201	* folio
	202	* @folio: The folio.
	203	*
	204	* The average number of user page table entries that reference each page in
	205	* this folio as tracked via the RMAP: either referenced directly (PTE) or
	206	* as part of a larger area that covers this page (e.g., PMD).
	207	*
	208	* The average is calculated by rounding to the nearest integer; however,
	209	* to avoid duplicated code in current callers, the average is at least
	210	* 1 if any page of the folio is mapped.
	211	*
	212	* Returns: The average number of mappings per page in this folio.
	213	*/
	214	static inline int folio_average_page_mapcount(struct folio *folio)
	215	{
	216	int mapcount, entire_mapcount, avg;
	217
	218	if (!folio_test_large(folio))
	219	return atomic_read(&folio->_mapcount) + 1;
	220
	221	mapcount = folio_large_mapcount(folio);
	222	if (unlikely(mapcount <= 0))
	223	return 0;
	224	entire_mapcount = folio_entire_mapcount(folio);
	225	if (mapcount <= entire_mapcount)
	226	return entire_mapcount;
	227	mapcount -= entire_mapcount;
	228
	229	/* Round to closest integer ... */
	230	avg = ((unsigned int)mapcount + folio_large_nr_pages(folio) / 2) >> folio_large_order(folio);
	231	/* ... but return at least 1. */
	232	return max_t(int, avg + entire_mapcount, 1);
	233	}
	234	/*
	235	* array.c
	236	*/
	237	extern const struct file_operations proc_tid_children_operations;
	238
	239	extern void proc_task_name(struct seq_file m, struct task_struct p,
	240	bool escape);
	241	extern int proc_tid_stat(struct seq_file , struct pid_namespace ,
	242	struct pid , struct task_struct );
	243	extern int proc_tgid_stat(struct seq_file , struct pid_namespace ,
	244	struct pid , struct task_struct );
	245	extern int proc_pid_status(struct seq_file , struct pid_namespace ,
	246	struct pid , struct task_struct );
	247	extern int proc_pid_statm(struct seq_file , struct pid_namespace ,
	248	struct pid , struct task_struct );
	249
	250	/*
	251	* base.c
	252	*/
	253	extern const struct dentry_operations pid_dentry_operations;
	254	extern int pid_getattr(struct mnt_idmap , const struct path ,
	255	struct kstat *, u32, unsigned int);
	256	extern int proc_setattr(struct mnt_idmap , struct dentry ,
	257	struct iattr *);
	258	extern void proc_pid_evict_inode(struct proc_inode *);
	259	extern struct inode proc_pid_make_inode(struct super_block , struct task_struct *, umode_t);
	260	extern void pid_update_inode(struct task_struct , struct inode );
	261	extern int pid_delete_dentry(const struct dentry *);
	262	extern int proc_pid_readdir(struct file , struct dir_context );
	263	struct dentry proc_pid_lookup(struct dentry , unsigned int);
	264	extern loff_t mem_lseek(struct file *, loff_t, int);
	265
	266	/* Lookups */
	267	typedef struct dentry instantiate_t(struct dentry ,
	268	struct task_struct , const void );
	269	bool proc_fill_cache(struct file , struct dir_context , const char *, unsigned int,
	270	instantiate_t, struct task_struct , const void );
	271
	272	/*
	273	* generic.c
	274	*/
	275	struct proc_dir_entry proc_create_reg(const char name, umode_t mode,
	276	struct proc_dir_entry *parent, void data);
	277	struct proc_dir_entry proc_register(struct proc_dir_entry dir,
	278	struct proc_dir_entry *dp);
	279	extern struct dentry proc_lookup(struct inode , struct dentry *, unsigned int);
	280	struct dentry proc_lookup_de(struct inode , struct dentry , struct proc_dir_entry );
	281	extern int proc_readdir(struct file , struct dir_context );
	282	int proc_readdir_de(struct file , struct dir_context , struct proc_dir_entry *);
	283
	284	static inline void pde_get(struct proc_dir_entry *pde)
	285	{
	286	refcount_inc(&pde->refcnt);
	287	}
	288	extern void pde_put(struct proc_dir_entry *);
	289
	290	static inline bool is_empty_pde(const struct proc_dir_entry *pde)
	291	{
	292	return S_ISDIR(pde->mode) && !pde->proc_iops;
	293	}
	294	extern ssize_t proc_simple_write(struct file , const char __user , size_t, loff_t *);
	295
	296	/*
	297	* inode.c
	298	*/
	299	struct pde_opener {
	300	struct list_head lh;
	301	struct file *file;
	302	bool closing;
	303	struct completion *c;
	304	} __randomize_layout;
	305	extern const struct inode_operations proc_link_inode_operations;
	306	extern const struct inode_operations proc_pid_link_inode_operations;
	307	extern const struct super_operations proc_sops;
	308
	309	void proc_init_kmemcache(void);
	310	void proc_invalidate_siblings_dcache(struct hlist_head inodes, spinlock_t lock);
	311	void set_proc_pid_nlink(void);
	312	extern struct inode proc_get_inode(struct super_block , struct proc_dir_entry *);
	313	extern void proc_entry_rundown(struct proc_dir_entry *);
	314
	315	/*
	316	* proc_namespaces.c
	317	*/
	318	extern const struct inode_operations proc_ns_dir_inode_operations;
	319	extern const struct file_operations proc_ns_dir_operations;
	320
	321	/*
	322	* proc_net.c
	323	*/
	324	extern const struct file_operations proc_net_operations;
	325	extern const struct inode_operations proc_net_inode_operations;
	326
	327	#ifdef CONFIG_NET
	328	extern int proc_net_init(void);
	329	#else
	330	static inline int proc_net_init(void) { return 0; }
	331	#endif
	332
	333	/*
	334	* proc_self.c
	335	*/
	336	extern int proc_setup_self(struct super_block *);
	337
	338	/*
	339	* proc_thread_self.c
	340	*/
	341	extern int proc_setup_thread_self(struct super_block *);
	342	extern void proc_thread_self_init(void);
	343
	344	/*
	345	* proc_sysctl.c
	346	*/
	347	#ifdef CONFIG_PROC_SYSCTL
	348	extern int proc_sys_init(void);
	349	extern void proc_sys_evict_inode(struct inode *inode,
	350	struct ctl_table_header *head);
	351	#else
	352	static inline void proc_sys_init(void) { }
	353	static inline void proc_sys_evict_inode(struct inode *inode,
	354	struct ctl_table_header *head) { }
	355	#endif
	356
	357	/*
	358	* proc_tty.c
	359	*/
	360	#ifdef CONFIG_TTY
	361	extern void proc_tty_init(void);
	362	#else
	363	static inline void proc_tty_init(void) {}
	364	#endif
	365
	366	/*
	367	* root.c
	368	*/
	369	extern struct proc_dir_entry proc_root;
	370
	371	extern void proc_self_init(void);
	372
	373	/*
	374	* task_[no]mmu.c
	375	*/
	376	struct mem_size_stats;
	377	struct proc_maps_private {
	378	struct inode *inode;
	379	struct task_struct *task;
	380	struct mm_struct *mm;
	381	struct vma_iterator iter;
	382	#ifdef CONFIG_NUMA
	383	struct mempolicy *task_mempolicy;
	384	#endif
	385	} __randomize_layout;
	386
	387	struct mm_struct proc_mem_open(struct inode inode, unsigned int mode);
	388
	389	extern const struct file_operations proc_pid_maps_operations;
	390	extern const struct file_operations proc_pid_numa_maps_operations;
	391	extern const struct file_operations proc_pid_smaps_operations;
	392	extern const struct file_operations proc_pid_smaps_rollup_operations;
	393	extern const struct file_operations proc_clear_refs_operations;
	394	extern const struct file_operations proc_pagemap_operations;
	395
	396	extern unsigned long task_vsize(struct mm_struct *);
	397	extern unsigned long task_statm(struct mm_struct *,
	398	unsigned long , unsigned long ,
	399	unsigned long , unsigned long );
	400	extern void task_mem(struct seq_file , struct mm_struct );
	401
	402	extern const struct dentry_operations proc_net_dentry_ops;
	403	static inline void pde_force_lookup(struct proc_dir_entry *pde)
	404	{
	405	/* /proc/net/ entries can be changed under us by setns(CLONE_NEWNET) */
	406	pde->proc_dops = &proc_net_dentry_ops;
	407	}
	408
	409	/*
	410	* Add a new procfs dentry that can't serve as a mountpoint. That should
	411	* encompass anything that is ephemeral and can just disappear while the
	412	* process is still around.
	413	*/
	414	static inline struct dentry proc_splice_unmountable(struct inode inode,
	415	struct dentry dentry, const struct dentry_operations d_ops)
	416	{
	417	d_set_d_op(dentry, d_ops);
	418	dont_mount(dentry);
	419	return d_splice_alias(inode, dentry);
	420	}