| 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 | #else |
| 27 | static inline void bdev_cache_init(void) |
| 28 | { |
| 29 | } |
| 30 | #endif /* CONFIG_BLOCK */ |
| 31 | |
| 32 | /* |
| 33 | * buffer.c |
| 34 | */ |
| 35 | int __block_write_begin_int(struct folio *folio, loff_t pos, unsigned len, |
| 36 | get_block_t *get_block, const struct iomap *iomap); |
| 37 | |
| 38 | /* |
| 39 | * char_dev.c |
| 40 | */ |
| 41 | extern void __init chrdev_init(void); |
| 42 | |
| 43 | /* |
| 44 | * fs_context.c |
| 45 | */ |
| 46 | extern const struct fs_context_operations legacy_fs_context_ops; |
| 47 | extern int parse_monolithic_mount_data(struct fs_context *, void *); |
| 48 | extern void vfs_clean_context(struct fs_context *fc); |
| 49 | extern int finish_clean_context(struct fs_context *fc); |
| 50 | |
| 51 | /* |
| 52 | * namei.c |
| 53 | */ |
| 54 | extern int filename_lookup(int dfd, struct filename *name, unsigned flags, |
| 55 | struct path *path, struct path *root); |
| 56 | int do_rmdir(int dfd, struct filename *name); |
| 57 | int do_unlinkat(int dfd, struct filename *name); |
| 58 | int may_linkat(struct mnt_idmap *idmap, const struct path *link); |
| 59 | int do_renameat2(int olddfd, struct filename *oldname, int newdfd, |
| 60 | struct filename *newname, unsigned int flags); |
| 61 | int do_mkdirat(int dfd, struct filename *name, umode_t mode); |
| 62 | int do_symlinkat(struct filename *from, int newdfd, struct filename *to); |
| 63 | int do_linkat(int olddfd, struct filename *old, int newdfd, |
| 64 | struct filename *new, int flags); |
| 65 | |
| 66 | /* |
| 67 | * namespace.c |
| 68 | */ |
| 69 | extern struct vfsmount *lookup_mnt(const struct path *); |
| 70 | extern int finish_automount(struct vfsmount *, const struct path *); |
| 71 | |
| 72 | extern int sb_prepare_remount_readonly(struct super_block *); |
| 73 | |
| 74 | extern void __init mnt_init(void); |
| 75 | |
| 76 | int mnt_get_write_access_file(struct file *file); |
| 77 | void mnt_put_write_access_file(struct file *file); |
| 78 | |
| 79 | extern void dissolve_on_fput(struct vfsmount *); |
| 80 | extern bool may_mount(void); |
| 81 | |
| 82 | int path_mount(const char *dev_name, struct path *path, |
| 83 | const char *type_page, unsigned long flags, void *data_page); |
| 84 | int path_umount(struct path *path, int flags); |
| 85 | |
| 86 | int show_path(struct seq_file *m, struct dentry *root); |
| 87 | |
| 88 | /* |
| 89 | * fs_struct.c |
| 90 | */ |
| 91 | extern void chroot_fs_refs(const struct path *, const struct path *); |
| 92 | |
| 93 | /* |
| 94 | * file_table.c |
| 95 | */ |
| 96 | struct file *alloc_empty_file(int flags, const struct cred *cred); |
| 97 | struct file *alloc_empty_file_noaccount(int flags, const struct cred *cred); |
| 98 | struct file *alloc_empty_backing_file(int flags, const struct cred *cred); |
| 99 | |
| 100 | static inline void file_put_write_access(struct file *file) |
| 101 | { |
| 102 | put_write_access(file->f_inode); |
| 103 | mnt_put_write_access(file->f_path.mnt); |
| 104 | if (unlikely(file->f_mode & FMODE_BACKING)) |
| 105 | mnt_put_write_access(backing_file_user_path(file)->mnt); |
| 106 | } |
| 107 | |
| 108 | static inline void put_file_access(struct file *file) |
| 109 | { |
| 110 | if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) { |
| 111 | i_readcount_dec(file->f_inode); |
| 112 | } else if (file->f_mode & FMODE_WRITER) { |
| 113 | file_put_write_access(file); |
| 114 | } |
| 115 | } |
| 116 | |
| 117 | /* |
| 118 | * super.c |
| 119 | */ |
| 120 | extern int reconfigure_super(struct fs_context *); |
| 121 | extern bool super_trylock_shared(struct super_block *sb); |
| 122 | struct super_block *user_get_super(dev_t, bool excl); |
| 123 | void put_super(struct super_block *sb); |
| 124 | extern bool mount_capable(struct fs_context *); |
| 125 | int sb_init_dio_done_wq(struct super_block *sb); |
| 126 | |
| 127 | /* |
| 128 | * Prepare superblock for changing its read-only state (i.e., either remount |
| 129 | * read-write superblock read-only or vice versa). After this function returns |
| 130 | * mnt_is_readonly() will return true for any mount of the superblock if its |
| 131 | * caller is able to observe any changes done by the remount. This holds until |
| 132 | * sb_end_ro_state_change() is called. |
| 133 | */ |
| 134 | static inline void sb_start_ro_state_change(struct super_block *sb) |
| 135 | { |
| 136 | WRITE_ONCE(sb->s_readonly_remount, 1); |
| 137 | /* |
| 138 | * For RO->RW transition, the barrier pairs with the barrier in |
| 139 | * mnt_is_readonly() making sure if mnt_is_readonly() sees SB_RDONLY |
| 140 | * cleared, it will see s_readonly_remount set. |
| 141 | * For RW->RO transition, the barrier pairs with the barrier in |
| 142 | * mnt_get_write_access() before the mnt_is_readonly() check. |
| 143 | * The barrier makes sure if mnt_get_write_access() sees MNT_WRITE_HOLD |
| 144 | * already cleared, it will see s_readonly_remount set. |
| 145 | */ |
| 146 | smp_wmb(); |
| 147 | } |
| 148 | |
| 149 | /* |
| 150 | * Ends section changing read-only state of the superblock. After this function |
| 151 | * returns if mnt_is_readonly() returns false, the caller will be able to |
| 152 | * observe all the changes remount did to the superblock. |
| 153 | */ |
| 154 | static inline void sb_end_ro_state_change(struct super_block *sb) |
| 155 | { |
| 156 | /* |
| 157 | * This barrier provides release semantics that pairs with |
| 158 | * the smp_rmb() acquire semantics in mnt_is_readonly(). |
| 159 | * This barrier pair ensure that when mnt_is_readonly() sees |
| 160 | * 0 for sb->s_readonly_remount, it will also see all the |
| 161 | * preceding flag changes that were made during the RO state |
| 162 | * change. |
| 163 | */ |
| 164 | smp_wmb(); |
| 165 | WRITE_ONCE(sb->s_readonly_remount, 0); |
| 166 | } |
| 167 | |
| 168 | /* |
| 169 | * open.c |
| 170 | */ |
| 171 | struct open_flags { |
| 172 | int open_flag; |
| 173 | umode_t mode; |
| 174 | int acc_mode; |
| 175 | int intent; |
| 176 | int lookup_flags; |
| 177 | }; |
| 178 | extern struct file *do_filp_open(int dfd, struct filename *pathname, |
| 179 | const struct open_flags *op); |
| 180 | extern struct file *do_file_open_root(const struct path *, |
| 181 | const char *, const struct open_flags *); |
| 182 | extern struct open_how build_open_how(int flags, umode_t mode); |
| 183 | extern int build_open_flags(const struct open_how *how, struct open_flags *op); |
| 184 | struct file *file_close_fd_locked(struct files_struct *files, unsigned fd); |
| 185 | |
| 186 | long do_ftruncate(struct file *file, loff_t length, int small); |
| 187 | long do_sys_ftruncate(unsigned int fd, loff_t length, int small); |
| 188 | int chmod_common(const struct path *path, umode_t mode); |
| 189 | int do_fchownat(int dfd, const char __user *filename, uid_t user, gid_t group, |
| 190 | int flag); |
| 191 | int chown_common(const struct path *path, uid_t user, gid_t group); |
| 192 | extern int vfs_open(const struct path *, struct file *); |
| 193 | |
| 194 | /* |
| 195 | * inode.c |
| 196 | */ |
| 197 | extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc); |
| 198 | int dentry_needs_remove_privs(struct mnt_idmap *, struct dentry *dentry); |
| 199 | bool in_group_or_capable(struct mnt_idmap *idmap, |
| 200 | const struct inode *inode, vfsgid_t vfsgid); |
| 201 | |
| 202 | /* |
| 203 | * fs-writeback.c |
| 204 | */ |
| 205 | extern long get_nr_dirty_inodes(void); |
| 206 | void invalidate_inodes(struct super_block *sb); |
| 207 | |
| 208 | /* |
| 209 | * dcache.c |
| 210 | */ |
| 211 | extern int d_set_mounted(struct dentry *dentry); |
| 212 | extern long prune_dcache_sb(struct super_block *sb, struct shrink_control *sc); |
| 213 | extern struct dentry *d_alloc_cursor(struct dentry *); |
| 214 | extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *); |
| 215 | extern char *simple_dname(struct dentry *, char *, int); |
| 216 | extern void dput_to_list(struct dentry *, struct list_head *); |
| 217 | extern void shrink_dentry_list(struct list_head *); |
| 218 | extern void shrink_dcache_for_umount(struct super_block *); |
| 219 | extern struct dentry *__d_lookup(const struct dentry *, const struct qstr *); |
| 220 | extern struct dentry *__d_lookup_rcu(const struct dentry *parent, |
| 221 | const struct qstr *name, unsigned *seq); |
| 222 | extern void d_genocide(struct dentry *); |
| 223 | |
| 224 | /* |
| 225 | * pipe.c |
| 226 | */ |
| 227 | extern const struct file_operations pipefifo_fops; |
| 228 | |
| 229 | /* |
| 230 | * fs_pin.c |
| 231 | */ |
| 232 | extern void group_pin_kill(struct hlist_head *p); |
| 233 | extern void mnt_pin_kill(struct mount *m); |
| 234 | |
| 235 | /* |
| 236 | * fs/nsfs.c |
| 237 | */ |
| 238 | extern const struct dentry_operations ns_dentry_operations; |
| 239 | |
| 240 | /* |
| 241 | * fs/stat.c: |
| 242 | */ |
| 243 | |
| 244 | int getname_statx_lookup_flags(int flags); |
| 245 | int do_statx(int dfd, struct filename *filename, unsigned int flags, |
| 246 | unsigned int mask, struct statx __user *buffer); |
| 247 | |
| 248 | /* |
| 249 | * fs/splice.c: |
| 250 | */ |
| 251 | ssize_t splice_file_to_pipe(struct file *in, |
| 252 | struct pipe_inode_info *opipe, |
| 253 | loff_t *offset, |
| 254 | size_t len, unsigned int flags); |
| 255 | |
| 256 | /* |
| 257 | * fs/xattr.c: |
| 258 | */ |
| 259 | struct xattr_name { |
| 260 | char name[XATTR_NAME_MAX + 1]; |
| 261 | }; |
| 262 | |
| 263 | struct xattr_ctx { |
| 264 | /* Value of attribute */ |
| 265 | union { |
| 266 | const void __user *cvalue; |
| 267 | void __user *value; |
| 268 | }; |
| 269 | void *kvalue; |
| 270 | size_t size; |
| 271 | /* Attribute name */ |
| 272 | struct xattr_name *kname; |
| 273 | unsigned int flags; |
| 274 | }; |
| 275 | |
| 276 | |
| 277 | ssize_t do_getxattr(struct mnt_idmap *idmap, |
| 278 | struct dentry *d, |
| 279 | struct xattr_ctx *ctx); |
| 280 | |
| 281 | int setxattr_copy(const char __user *name, struct xattr_ctx *ctx); |
| 282 | int do_setxattr(struct mnt_idmap *idmap, struct dentry *dentry, |
| 283 | struct xattr_ctx *ctx); |
| 284 | int may_write_xattr(struct mnt_idmap *idmap, struct inode *inode); |
| 285 | |
| 286 | #ifdef CONFIG_FS_POSIX_ACL |
| 287 | int do_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, |
| 288 | const char *acl_name, const void *kvalue, size_t size); |
| 289 | ssize_t do_get_acl(struct mnt_idmap *idmap, struct dentry *dentry, |
| 290 | const char *acl_name, void *kvalue, size_t size); |
| 291 | #else |
| 292 | static inline int do_set_acl(struct mnt_idmap *idmap, |
| 293 | struct dentry *dentry, const char *acl_name, |
| 294 | const void *kvalue, size_t size) |
| 295 | { |
| 296 | return -EOPNOTSUPP; |
| 297 | } |
| 298 | static inline ssize_t do_get_acl(struct mnt_idmap *idmap, |
| 299 | struct dentry *dentry, const char *acl_name, |
| 300 | void *kvalue, size_t size) |
| 301 | { |
| 302 | return -EOPNOTSUPP; |
| 303 | } |
| 304 | #endif |
| 305 | |
| 306 | ssize_t __kernel_write_iter(struct file *file, struct iov_iter *from, loff_t *pos); |
| 307 | |
| 308 | /* |
| 309 | * fs/attr.c |
| 310 | */ |
| 311 | struct mnt_idmap *alloc_mnt_idmap(struct user_namespace *mnt_userns); |
| 312 | struct mnt_idmap *mnt_idmap_get(struct mnt_idmap *idmap); |
| 313 | void mnt_idmap_put(struct mnt_idmap *idmap); |
| 314 | struct stashed_operations { |
| 315 | void (*put_data)(void *data); |
| 316 | void (*init_inode)(struct inode *inode, void *data); |
| 317 | }; |
| 318 | int path_from_stashed(struct dentry **stashed, unsigned long ino, |
| 319 | struct vfsmount *mnt, void *data, struct path *path); |
| 320 | void stashed_dentry_prune(struct dentry *dentry); |