xref: /linux/fs/internal.h (revision 0526b56cbc3c489642bd6a5fe4b718dea7ef0ee8)
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 int do_rmdir(int dfd, struct filename *name);
63 int do_unlinkat(int dfd, struct filename *name);
64 int may_linkat(struct mnt_idmap *idmap, const struct path *link);
65 int do_renameat2(int olddfd, struct filename *oldname, int newdfd,
66 		 struct filename *newname, unsigned int flags);
67 int do_mkdirat(int dfd, struct filename *name, umode_t mode);
68 int do_symlinkat(struct filename *from, int newdfd, struct filename *to);
69 int do_linkat(int olddfd, struct filename *old, int newdfd,
70 			struct filename *new, int flags);
71 
72 /*
73  * namespace.c
74  */
75 extern struct vfsmount *lookup_mnt(const struct path *);
76 extern int finish_automount(struct vfsmount *, const struct path *);
77 
78 extern int sb_prepare_remount_readonly(struct super_block *);
79 
80 extern void __init mnt_init(void);
81 
82 extern int __mnt_want_write_file(struct file *);
83 extern void __mnt_drop_write_file(struct file *);
84 
85 extern void dissolve_on_fput(struct vfsmount *);
86 extern bool may_mount(void);
87 
88 int path_mount(const char *dev_name, struct path *path,
89 		const char *type_page, unsigned long flags, void *data_page);
90 int path_umount(struct path *path, int flags);
91 
92 /*
93  * fs_struct.c
94  */
95 extern void chroot_fs_refs(const struct path *, const struct path *);
96 
97 /*
98  * file_table.c
99  */
100 extern struct file *alloc_empty_file(int, const struct cred *);
101 extern struct file *alloc_empty_file_noaccount(int, const struct cred *);
102 
103 static inline void put_file_access(struct file *file)
104 {
105 	if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) {
106 		i_readcount_dec(file->f_inode);
107 	} else if (file->f_mode & FMODE_WRITER) {
108 		put_write_access(file->f_inode);
109 		__mnt_drop_write(file->f_path.mnt);
110 	}
111 }
112 
113 /*
114  * super.c
115  */
116 extern int reconfigure_super(struct fs_context *);
117 extern bool trylock_super(struct super_block *sb);
118 struct super_block *user_get_super(dev_t, bool excl);
119 void put_super(struct super_block *sb);
120 extern bool mount_capable(struct fs_context *);
121 int sb_init_dio_done_wq(struct super_block *sb);
122 
123 /*
124  * open.c
125  */
126 struct open_flags {
127 	int open_flag;
128 	umode_t mode;
129 	int acc_mode;
130 	int intent;
131 	int lookup_flags;
132 };
133 extern struct file *do_filp_open(int dfd, struct filename *pathname,
134 		const struct open_flags *op);
135 extern struct file *do_file_open_root(const struct path *,
136 		const char *, const struct open_flags *);
137 extern struct open_how build_open_how(int flags, umode_t mode);
138 extern int build_open_flags(const struct open_how *how, struct open_flags *op);
139 extern struct file *__close_fd_get_file(unsigned int fd);
140 
141 long do_sys_ftruncate(unsigned int fd, loff_t length, int small);
142 int chmod_common(const struct path *path, umode_t mode);
143 int do_fchownat(int dfd, const char __user *filename, uid_t user, gid_t group,
144 		int flag);
145 int chown_common(const struct path *path, uid_t user, gid_t group);
146 extern int vfs_open(const struct path *, struct file *);
147 
148 /*
149  * inode.c
150  */
151 extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc);
152 int dentry_needs_remove_privs(struct mnt_idmap *, struct dentry *dentry);
153 bool in_group_or_capable(struct mnt_idmap *idmap,
154 			 const struct inode *inode, vfsgid_t vfsgid);
155 
156 /*
157  * fs-writeback.c
158  */
159 extern long get_nr_dirty_inodes(void);
160 extern int invalidate_inodes(struct super_block *, bool);
161 
162 /*
163  * dcache.c
164  */
165 extern int d_set_mounted(struct dentry *dentry);
166 extern long prune_dcache_sb(struct super_block *sb, struct shrink_control *sc);
167 extern struct dentry *d_alloc_cursor(struct dentry *);
168 extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *);
169 extern char *simple_dname(struct dentry *, char *, int);
170 extern void dput_to_list(struct dentry *, struct list_head *);
171 extern void shrink_dentry_list(struct list_head *);
172 
173 /*
174  * pipe.c
175  */
176 extern const struct file_operations pipefifo_fops;
177 
178 /*
179  * fs_pin.c
180  */
181 extern void group_pin_kill(struct hlist_head *p);
182 extern void mnt_pin_kill(struct mount *m);
183 
184 /*
185  * fs/nsfs.c
186  */
187 extern const struct dentry_operations ns_dentry_operations;
188 
189 /*
190  * fs/stat.c:
191  */
192 
193 int getname_statx_lookup_flags(int flags);
194 int do_statx(int dfd, struct filename *filename, unsigned int flags,
195 	     unsigned int mask, struct statx __user *buffer);
196 
197 /*
198  * fs/splice.c:
199  */
200 long splice_file_to_pipe(struct file *in,
201 			 struct pipe_inode_info *opipe,
202 			 loff_t *offset,
203 			 size_t len, unsigned int flags);
204 
205 /*
206  * fs/xattr.c:
207  */
208 struct xattr_name {
209 	char name[XATTR_NAME_MAX + 1];
210 };
211 
212 struct xattr_ctx {
213 	/* Value of attribute */
214 	union {
215 		const void __user *cvalue;
216 		void __user *value;
217 	};
218 	void *kvalue;
219 	size_t size;
220 	/* Attribute name */
221 	struct xattr_name *kname;
222 	unsigned int flags;
223 };
224 
225 
226 ssize_t do_getxattr(struct mnt_idmap *idmap,
227 		    struct dentry *d,
228 		    struct xattr_ctx *ctx);
229 
230 int setxattr_copy(const char __user *name, struct xattr_ctx *ctx);
231 int do_setxattr(struct mnt_idmap *idmap, struct dentry *dentry,
232 		struct xattr_ctx *ctx);
233 int may_write_xattr(struct mnt_idmap *idmap, struct inode *inode);
234 
235 #ifdef CONFIG_FS_POSIX_ACL
236 int do_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
237 	       const char *acl_name, const void *kvalue, size_t size);
238 ssize_t do_get_acl(struct mnt_idmap *idmap, struct dentry *dentry,
239 		   const char *acl_name, void *kvalue, size_t size);
240 #else
241 static inline int do_set_acl(struct mnt_idmap *idmap,
242 			     struct dentry *dentry, const char *acl_name,
243 			     const void *kvalue, size_t size)
244 {
245 	return -EOPNOTSUPP;
246 }
247 static inline ssize_t do_get_acl(struct mnt_idmap *idmap,
248 				 struct dentry *dentry, const char *acl_name,
249 				 void *kvalue, size_t size)
250 {
251 	return -EOPNOTSUPP;
252 }
253 #endif
254 
255 ssize_t __kernel_write_iter(struct file *file, struct iov_iter *from, loff_t *pos);
256 
257 /*
258  * fs/attr.c
259  */
260 struct mnt_idmap *alloc_mnt_idmap(struct user_namespace *mnt_userns);
261 struct mnt_idmap *mnt_idmap_get(struct mnt_idmap *idmap);
262 void mnt_idmap_put(struct mnt_idmap *idmap);
263