xref: /linux/fs/internal.h (revision 811f35ff59b6f99ae272d6f5b96bc9e974f88196)
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 user_namespace;
18 struct pipe_inode_info;
19 struct iov_iter;
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 user_namespace *mnt_userns, 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 
124 /*
125  * open.c
126  */
127 struct open_flags {
128 	int open_flag;
129 	umode_t mode;
130 	int acc_mode;
131 	int intent;
132 	int lookup_flags;
133 };
134 extern struct file *do_filp_open(int dfd, struct filename *pathname,
135 		const struct open_flags *op);
136 extern struct file *do_file_open_root(const struct path *,
137 		const char *, const struct open_flags *);
138 extern struct open_how build_open_how(int flags, umode_t mode);
139 extern int build_open_flags(const struct open_how *how, struct open_flags *op);
140 extern struct file *__close_fd_get_file(unsigned int fd);
141 
142 long do_sys_ftruncate(unsigned int fd, loff_t length, int small);
143 int chmod_common(const struct path *path, umode_t mode);
144 int do_fchownat(int dfd, const char __user *filename, uid_t user, gid_t group,
145 		int flag);
146 int chown_common(const struct path *path, uid_t user, gid_t group);
147 extern int vfs_open(const struct path *, struct file *);
148 
149 /*
150  * inode.c
151  */
152 extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc);
153 int dentry_needs_remove_privs(struct user_namespace *, struct dentry *dentry);
154 bool in_group_or_capable(struct user_namespace *mnt_userns,
155 			 const struct inode *inode, vfsgid_t vfsgid);
156 
157 /*
158  * fs-writeback.c
159  */
160 extern long get_nr_dirty_inodes(void);
161 extern int invalidate_inodes(struct super_block *, bool);
162 
163 /*
164  * dcache.c
165  */
166 extern int d_set_mounted(struct dentry *dentry);
167 extern long prune_dcache_sb(struct super_block *sb, struct shrink_control *sc);
168 extern struct dentry *d_alloc_cursor(struct dentry *);
169 extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *);
170 extern char *simple_dname(struct dentry *, char *, int);
171 extern void dput_to_list(struct dentry *, struct list_head *);
172 extern void shrink_dentry_list(struct list_head *);
173 
174 /*
175  * pipe.c
176  */
177 extern const struct file_operations pipefifo_fops;
178 
179 /*
180  * fs_pin.c
181  */
182 extern void group_pin_kill(struct hlist_head *p);
183 extern void mnt_pin_kill(struct mount *m);
184 
185 /*
186  * fs/nsfs.c
187  */
188 extern const struct dentry_operations ns_dentry_operations;
189 
190 /* direct-io.c: */
191 int sb_init_dio_done_wq(struct super_block *sb);
192 
193 /*
194  * fs/stat.c:
195  */
196 
197 int getname_statx_lookup_flags(int flags);
198 int do_statx(int dfd, struct filename *filename, unsigned int flags,
199 	     unsigned int mask, struct statx __user *buffer);
200 
201 /*
202  * fs/splice.c:
203  */
204 long splice_file_to_pipe(struct file *in,
205 			 struct pipe_inode_info *opipe,
206 			 loff_t *offset,
207 			 size_t len, unsigned int flags);
208 
209 /*
210  * fs/xattr.c:
211  */
212 struct xattr_name {
213 	char name[XATTR_NAME_MAX + 1];
214 };
215 
216 struct xattr_ctx {
217 	/* Value of attribute */
218 	union {
219 		const void __user *cvalue;
220 		void __user *value;
221 	};
222 	void *kvalue;
223 	size_t size;
224 	/* Attribute name */
225 	struct xattr_name *kname;
226 	unsigned int flags;
227 };
228 
229 
230 ssize_t do_getxattr(struct mnt_idmap *idmap,
231 		    struct dentry *d,
232 		    struct xattr_ctx *ctx);
233 
234 int setxattr_copy(const char __user *name, struct xattr_ctx *ctx);
235 int do_setxattr(struct mnt_idmap *idmap, struct dentry *dentry,
236 		struct xattr_ctx *ctx);
237 int may_write_xattr(struct user_namespace *mnt_userns, struct inode *inode);
238 
239 #ifdef CONFIG_FS_POSIX_ACL
240 int do_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
241 	       const char *acl_name, const void *kvalue, size_t size);
242 ssize_t do_get_acl(struct mnt_idmap *idmap, struct dentry *dentry,
243 		   const char *acl_name, void *kvalue, size_t size);
244 #else
245 static inline int do_set_acl(struct mnt_idmap *idmap,
246 			     struct dentry *dentry, const char *acl_name,
247 			     const void *kvalue, size_t size)
248 {
249 	return -EOPNOTSUPP;
250 }
251 static inline ssize_t do_get_acl(struct mnt_idmap *idmap,
252 				 struct dentry *dentry, const char *acl_name,
253 				 void *kvalue, size_t size)
254 {
255 	return -EOPNOTSUPP;
256 }
257 #endif
258 
259 ssize_t __kernel_write_iter(struct file *file, struct iov_iter *from, loff_t *pos);
260 
261 /*
262  * fs/attr.c
263  */
264 int setattr_should_drop_sgid(struct user_namespace *mnt_userns,
265 			     const struct inode *inode);
266