xref: /linux/fs/internal.h (revision 0e9ab8e4d44ae9d9aaf213bfd2c90bbe7289337b)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* fs/ internal definitions
3  *
4  * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
5  * Written by David Howells (dhowells@redhat.com)
6  */
7 
8 struct super_block;
9 struct file_system_type;
10 struct iomap;
11 struct iomap_ops;
12 struct linux_binprm;
13 struct path;
14 struct mount;
15 struct shrink_control;
16 struct fs_context;
17 struct pipe_inode_info;
18 struct iov_iter;
19 struct mnt_idmap;
20 
21 /*
22  * block/bdev.c
23  */
24 #ifdef CONFIG_BLOCK
25 extern void __init bdev_cache_init(void);
26 
27 void emergency_thaw_bdev(struct super_block *sb);
28 #else
29 static inline void bdev_cache_init(void)
30 {
31 }
32 static inline int emergency_thaw_bdev(struct super_block *sb)
33 {
34 	return 0;
35 }
36 #endif /* CONFIG_BLOCK */
37 
38 /*
39  * buffer.c
40  */
41 int __block_write_begin_int(struct folio *folio, loff_t pos, unsigned len,
42 		get_block_t *get_block, const struct iomap *iomap);
43 
44 /*
45  * char_dev.c
46  */
47 extern void __init chrdev_init(void);
48 
49 /*
50  * fs_context.c
51  */
52 extern const struct fs_context_operations legacy_fs_context_ops;
53 extern int parse_monolithic_mount_data(struct fs_context *, void *);
54 extern void vfs_clean_context(struct fs_context *fc);
55 extern int finish_clean_context(struct fs_context *fc);
56 
57 /*
58  * namei.c
59  */
60 extern int filename_lookup(int dfd, struct filename *name, unsigned flags,
61 			   struct path *path, struct path *root);
62 extern int vfs_path_lookup(struct dentry *, struct vfsmount *,
63 			   const char *, unsigned int, struct path *);
64 int do_rmdir(int dfd, struct filename *name);
65 int do_unlinkat(int dfd, struct filename *name);
66 int may_linkat(struct mnt_idmap *idmap, const struct path *link);
67 int do_renameat2(int olddfd, struct filename *oldname, int newdfd,
68 		 struct filename *newname, unsigned int flags);
69 int do_mkdirat(int dfd, struct filename *name, umode_t mode);
70 int do_symlinkat(struct filename *from, int newdfd, struct filename *to);
71 int do_linkat(int olddfd, struct filename *old, int newdfd,
72 			struct filename *new, int flags);
73 
74 /*
75  * namespace.c
76  */
77 extern struct vfsmount *lookup_mnt(const struct path *);
78 extern int finish_automount(struct vfsmount *, const struct path *);
79 
80 extern int sb_prepare_remount_readonly(struct super_block *);
81 
82 extern void __init mnt_init(void);
83 
84 extern int __mnt_want_write_file(struct file *);
85 extern void __mnt_drop_write_file(struct file *);
86 
87 extern void dissolve_on_fput(struct vfsmount *);
88 extern bool may_mount(void);
89 
90 int path_mount(const char *dev_name, struct path *path,
91 		const char *type_page, unsigned long flags, void *data_page);
92 int path_umount(struct path *path, int flags);
93 
94 /*
95  * fs_struct.c
96  */
97 extern void chroot_fs_refs(const struct path *, const struct path *);
98 
99 /*
100  * file_table.c
101  */
102 extern struct file *alloc_empty_file(int, const struct cred *);
103 extern struct file *alloc_empty_file_noaccount(int, const struct cred *);
104 
105 static inline void put_file_access(struct file *file)
106 {
107 	if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) {
108 		i_readcount_dec(file->f_inode);
109 	} else if (file->f_mode & FMODE_WRITER) {
110 		put_write_access(file->f_inode);
111 		__mnt_drop_write(file->f_path.mnt);
112 	}
113 }
114 
115 /*
116  * super.c
117  */
118 extern int reconfigure_super(struct fs_context *);
119 extern bool trylock_super(struct super_block *sb);
120 struct super_block *user_get_super(dev_t, bool excl);
121 void put_super(struct super_block *sb);
122 extern bool mount_capable(struct fs_context *);
123 int sb_init_dio_done_wq(struct super_block *sb);
124 
125 /*
126  * open.c
127  */
128 struct open_flags {
129 	int open_flag;
130 	umode_t mode;
131 	int acc_mode;
132 	int intent;
133 	int lookup_flags;
134 };
135 extern struct file *do_filp_open(int dfd, struct filename *pathname,
136 		const struct open_flags *op);
137 extern struct file *do_file_open_root(const struct path *,
138 		const char *, const struct open_flags *);
139 extern struct open_how build_open_how(int flags, umode_t mode);
140 extern int build_open_flags(const struct open_how *how, struct open_flags *op);
141 extern struct file *__close_fd_get_file(unsigned int fd);
142 
143 long do_sys_ftruncate(unsigned int fd, loff_t length, int small);
144 int chmod_common(const struct path *path, umode_t mode);
145 int do_fchownat(int dfd, const char __user *filename, uid_t user, gid_t group,
146 		int flag);
147 int chown_common(const struct path *path, uid_t user, gid_t group);
148 extern int vfs_open(const struct path *, struct file *);
149 
150 /*
151  * inode.c
152  */
153 extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc);
154 int dentry_needs_remove_privs(struct mnt_idmap *, struct dentry *dentry);
155 bool in_group_or_capable(struct mnt_idmap *idmap,
156 			 const struct inode *inode, vfsgid_t vfsgid);
157 
158 /*
159  * fs-writeback.c
160  */
161 extern long get_nr_dirty_inodes(void);
162 extern int invalidate_inodes(struct super_block *, bool);
163 
164 /*
165  * dcache.c
166  */
167 extern int d_set_mounted(struct dentry *dentry);
168 extern long prune_dcache_sb(struct super_block *sb, struct shrink_control *sc);
169 extern struct dentry *d_alloc_cursor(struct dentry *);
170 extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *);
171 extern char *simple_dname(struct dentry *, char *, int);
172 extern void dput_to_list(struct dentry *, struct list_head *);
173 extern void shrink_dentry_list(struct list_head *);
174 
175 /*
176  * pipe.c
177  */
178 extern const struct file_operations pipefifo_fops;
179 
180 /*
181  * fs_pin.c
182  */
183 extern void group_pin_kill(struct hlist_head *p);
184 extern void mnt_pin_kill(struct mount *m);
185 
186 /*
187  * fs/nsfs.c
188  */
189 extern const struct dentry_operations ns_dentry_operations;
190 
191 /*
192  * fs/stat.c:
193  */
194 
195 int getname_statx_lookup_flags(int flags);
196 int do_statx(int dfd, struct filename *filename, unsigned int flags,
197 	     unsigned int mask, struct statx __user *buffer);
198 
199 /*
200  * fs/splice.c:
201  */
202 long splice_file_to_pipe(struct file *in,
203 			 struct pipe_inode_info *opipe,
204 			 loff_t *offset,
205 			 size_t len, unsigned int flags);
206 
207 /*
208  * fs/xattr.c:
209  */
210 struct xattr_name {
211 	char name[XATTR_NAME_MAX + 1];
212 };
213 
214 struct xattr_ctx {
215 	/* Value of attribute */
216 	union {
217 		const void __user *cvalue;
218 		void __user *value;
219 	};
220 	void *kvalue;
221 	size_t size;
222 	/* Attribute name */
223 	struct xattr_name *kname;
224 	unsigned int flags;
225 };
226 
227 
228 ssize_t do_getxattr(struct mnt_idmap *idmap,
229 		    struct dentry *d,
230 		    struct xattr_ctx *ctx);
231 
232 int setxattr_copy(const char __user *name, struct xattr_ctx *ctx);
233 int do_setxattr(struct mnt_idmap *idmap, struct dentry *dentry,
234 		struct xattr_ctx *ctx);
235 int may_write_xattr(struct mnt_idmap *idmap, struct inode *inode);
236 
237 #ifdef CONFIG_FS_POSIX_ACL
238 int do_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
239 	       const char *acl_name, const void *kvalue, size_t size);
240 ssize_t do_get_acl(struct mnt_idmap *idmap, struct dentry *dentry,
241 		   const char *acl_name, void *kvalue, size_t size);
242 #else
243 static inline int do_set_acl(struct mnt_idmap *idmap,
244 			     struct dentry *dentry, const char *acl_name,
245 			     const void *kvalue, size_t size)
246 {
247 	return -EOPNOTSUPP;
248 }
249 static inline ssize_t do_get_acl(struct mnt_idmap *idmap,
250 				 struct dentry *dentry, const char *acl_name,
251 				 void *kvalue, size_t size)
252 {
253 	return -EOPNOTSUPP;
254 }
255 #endif
256 
257 ssize_t __kernel_write_iter(struct file *file, struct iov_iter *from, loff_t *pos);
258 
259 /*
260  * fs/attr.c
261  */
262 int setattr_should_drop_sgid(struct mnt_idmap *idmap,
263 			     const struct inode *inode);
264 struct mnt_idmap *alloc_mnt_idmap(struct user_namespace *mnt_userns);
265 struct mnt_idmap *mnt_idmap_get(struct mnt_idmap *idmap);
266 void mnt_idmap_put(struct mnt_idmap *idmap);
267