UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity
OpenCloudOS-Kernel/fs/overlayfs/overlayfs.h

697 lines
23 KiB
C
Raw Blame History

/* SPDX-License-Identifier: GPL-2.0-only */
/*
*
* Copyright (C) 2011 Novell Inc.
*/
#include <linux/kernel.h>
#include <linux/uuid.h>
#include <linux/fs.h>
#include <linux/namei.h>
#include "ovl_entry.h"
#undef pr_fmt
#define pr_fmt(fmt) "overlayfs: " fmt
enum ovl_path_type {
__OVL_PATH_UPPER = (1 << 0),
__OVL_PATH_MERGE = (1 << 1),
__OVL_PATH_ORIGIN = (1 << 2),
};
#define OVL_TYPE_UPPER(type) ((type) & __OVL_PATH_UPPER)
#define OVL_TYPE_MERGE(type) ((type) & __OVL_PATH_MERGE)
#define OVL_TYPE_ORIGIN(type) ((type) & __OVL_PATH_ORIGIN)
#define OVL_XATTR_NAMESPACE "overlay."
#define OVL_XATTR_TRUSTED_PREFIX XATTR_TRUSTED_PREFIX OVL_XATTR_NAMESPACE
#define OVL_XATTR_USER_PREFIX XATTR_USER_PREFIX OVL_XATTR_NAMESPACE
enum ovl_xattr {
OVL_XATTR_OPAQUE,
OVL_XATTR_REDIRECT,
OVL_XATTR_ORIGIN,
OVL_XATTR_IMPURE,
OVL_XATTR_NLINK,
OVL_XATTR_UPPER,
OVL_XATTR_METACOPY,
OVL_XATTR_PROTATTR,
};
enum ovl_inode_flag {
/* Pure upper dir that may contain non pure upper entries */
OVL_IMPURE,
/* Non-merge dir that may contain whiteout entries */
OVL_WHITEOUTS,
OVL_INDEX,
OVL_UPPERDATA,
/* Inode number will remain constant over copy up. */
OVL_CONST_INO,
};
enum ovl_entry_flag {
OVL_E_UPPER_ALIAS,
OVL_E_OPAQUE,
OVL_E_CONNECTED,
};
enum {
OVL_XINO_OFF,
OVL_XINO_AUTO,
OVL_XINO_ON,
};
/*
* The tuple (fh,uuid) is a universal unique identifier for a copy up origin,
* where:
* origin.fh - exported file handle of the lower file
* origin.uuid - uuid of the lower filesystem
*/
#define OVL_FH_VERSION 0
#define OVL_FH_MAGIC 0xfb
/* CPU byte order required for fid decoding: */
#define OVL_FH_FLAG_BIG_ENDIAN (1 << 0)
#define OVL_FH_FLAG_ANY_ENDIAN (1 << 1)
/* Is the real inode encoded in fid an upper inode? */
#define OVL_FH_FLAG_PATH_UPPER (1 << 2)
#define OVL_FH_FLAG_ALL (OVL_FH_FLAG_BIG_ENDIAN | OVL_FH_FLAG_ANY_ENDIAN | \
OVL_FH_FLAG_PATH_UPPER)
#if defined(__LITTLE_ENDIAN)
#define OVL_FH_FLAG_CPU_ENDIAN 0
#elif defined(__BIG_ENDIAN)
#define OVL_FH_FLAG_CPU_ENDIAN OVL_FH_FLAG_BIG_ENDIAN
#else
#error Endianness not defined
#endif
/* The type used to be returned by overlay exportfs for misaligned fid */
#define OVL_FILEID_V0 0xfb
/* The type returned by overlay exportfs for 32bit aligned fid */
#define OVL_FILEID_V1 0xf8
/* On-disk format for "origin" file handle */
struct ovl_fb {
u8 version; /* 0 */
u8 magic; /* 0xfb */
u8 len; /* size of this header + size of fid */
u8 flags; /* OVL_FH_FLAG_* */
u8 type; /* fid_type of fid */
uuid_t uuid; /* uuid of filesystem */
u32 fid[]; /* file identifier should be 32bit aligned in-memory */
} __packed;
/* In-memory and on-wire format for overlay file handle */
struct ovl_fh {
u8 padding[3]; /* make sure fb.fid is 32bit aligned */
union {
struct ovl_fb fb;
u8 buf[0];
};
} __packed;
#define OVL_FH_WIRE_OFFSET offsetof(struct ovl_fh, fb)
#define OVL_FH_LEN(fh) (OVL_FH_WIRE_OFFSET + (fh)->fb.len)
#define OVL_FH_FID_OFFSET (OVL_FH_WIRE_OFFSET + \
offsetof(struct ovl_fb, fid))
extern const char *const ovl_xattr_table[][2];
static inline const char *ovl_xattr(struct ovl_fs *ofs, enum ovl_xattr ox)
{
return ovl_xattr_table[ox][ofs->config.userxattr];
}
/*
* When changing ownership of an upper object map the intended ownership
* according to the upper layer's idmapping. When an upper mount idmaps files
* that are stored on-disk as owned by id 1001 to id 1000 this means stat on
* this object will report it as being owned by id 1000 when calling stat via
* the upper mount.
* In order to change ownership of an object so stat reports id 1000 when
* called on an idmapped upper mount the value written to disk - i.e., the
* value stored in ia_*id - must 1001. The mount mapping helper will thus take
* care to map 1000 to 1001.
* The mnt idmapping helpers are nops if the upper layer isn't idmapped.
*/
static inline int ovl_do_notify_change(struct ovl_fs *ofs,
struct dentry *upperdentry,
struct iattr *attr)
{
return notify_change(ovl_upper_mnt_userns(ofs), upperdentry, attr, NULL);
}
static inline int ovl_do_rmdir(struct ovl_fs *ofs,
struct inode *dir, struct dentry *dentry)
{
int err = vfs_rmdir(ovl_upper_mnt_userns(ofs), dir, dentry);
pr_debug("rmdir(%pd2) = %i\n", dentry, err);
return err;
}
static inline int ovl_do_unlink(struct ovl_fs *ofs, struct inode *dir,
struct dentry *dentry)
{
int err = vfs_unlink(ovl_upper_mnt_userns(ofs), dir, dentry, NULL);
pr_debug("unlink(%pd2) = %i\n", dentry, err);
return err;
}
static inline int ovl_do_link(struct ovl_fs *ofs, struct dentry *old_dentry,
struct inode *dir, struct dentry *new_dentry)
{
int err = vfs_link(old_dentry, ovl_upper_mnt_userns(ofs), dir, new_dentry, NULL);
pr_debug("link(%pd2, %pd2) = %i\n", old_dentry, new_dentry, err);
return err;
}
static inline int ovl_do_create(struct ovl_fs *ofs,
struct inode *dir, struct dentry *dentry,
umode_t mode)
{
int err = vfs_create(ovl_upper_mnt_userns(ofs), dir, dentry, mode, true);
pr_debug("create(%pd2, 0%o) = %i\n", dentry, mode, err);
return err;
}
static inline int ovl_do_mkdir(struct ovl_fs *ofs,
struct inode *dir, struct dentry *dentry,
umode_t mode)
{
int err = vfs_mkdir(ovl_upper_mnt_userns(ofs), dir, dentry, mode);
pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry, mode, err);
return err;
}
static inline int ovl_do_mknod(struct ovl_fs *ofs,
struct inode *dir, struct dentry *dentry,
umode_t mode, dev_t dev)
{
int err = vfs_mknod(ovl_upper_mnt_userns(ofs), dir, dentry, mode, dev);
pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n", dentry, mode, dev, err);
return err;
}
static inline int ovl_do_symlink(struct ovl_fs *ofs,
struct inode *dir, struct dentry *dentry,
const char *oldname)
{
int err = vfs_symlink(ovl_upper_mnt_userns(ofs), dir, dentry, oldname);
pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname, dentry, err);
return err;
}
static inline ssize_t ovl_do_getxattr(const struct path *path, const char *name,
void *value, size_t size)
{
int err, len;
WARN_ON(path->dentry->d_sb != path->mnt->mnt_sb);
err = vfs_getxattr(mnt_user_ns(path->mnt), path->dentry,
name, value, size);
len = (value && err > 0) ? err : 0;
pr_debug("getxattr(%pd2, \"%s\", \"%*pE\", %zu, 0) = %i\n",
path->dentry, name, min(len, 48), value, size, err);
return err;
}
static inline ssize_t ovl_getxattr_upper(struct ovl_fs *ofs,
struct dentry *upperdentry,
enum ovl_xattr ox, void *value,
size_t size)
{
struct path upperpath = {
.dentry = upperdentry,
.mnt = ovl_upper_mnt(ofs),
};
return ovl_do_getxattr(&upperpath, ovl_xattr(ofs, ox), value, size);
}
static inline ssize_t ovl_path_getxattr(struct ovl_fs *ofs,
const struct path *path,
enum ovl_xattr ox, void *value,
size_t size)
{
return ovl_do_getxattr(path, ovl_xattr(ofs, ox), value, size);
}
static inline int ovl_do_setxattr(struct ovl_fs *ofs, struct dentry *dentry,
const char *name, const void *value,
size_t size, int flags)
{
int err = vfs_setxattr(ovl_upper_mnt_userns(ofs), dentry, name,
value, size, flags);
pr_debug("setxattr(%pd2, \"%s\", \"%*pE\", %zu, %d) = %i\n",
dentry, name, min((int)size, 48), value, size, flags, err);
return err;
}
static inline int ovl_setxattr(struct ovl_fs *ofs, struct dentry *dentry,
enum ovl_xattr ox, const void *value,
size_t size)
{
return ovl_do_setxattr(ofs, dentry, ovl_xattr(ofs, ox), value, size, 0);
}
static inline int ovl_do_removexattr(struct ovl_fs *ofs, struct dentry *dentry,
const char *name)
{
int err = vfs_removexattr(ovl_upper_mnt_userns(ofs), dentry, name);
pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry, name, err);
return err;
}
static inline int ovl_removexattr(struct ovl_fs *ofs, struct dentry *dentry,
enum ovl_xattr ox)
{
return ovl_do_removexattr(ofs, dentry, ovl_xattr(ofs, ox));
}
static inline int ovl_do_rename(struct ovl_fs *ofs, struct inode *olddir,
struct dentry *olddentry, struct inode *newdir,
struct dentry *newdentry, unsigned int flags)
{
int err;
struct renamedata rd = {
.old_mnt_userns = ovl_upper_mnt_userns(ofs),
.old_dir = olddir,
.old_dentry = olddentry,
.new_mnt_userns = ovl_upper_mnt_userns(ofs),
.new_dir = newdir,
.new_dentry = newdentry,
.flags = flags,
};
pr_debug("rename(%pd2, %pd2, 0x%x)\n", olddentry, newdentry, flags);
err = vfs_rename(&rd);
if (err) {
pr_debug("...rename(%pd2, %pd2, ...) = %i\n",
olddentry, newdentry, err);
}
return err;
}
static inline int ovl_do_whiteout(struct ovl_fs *ofs,
struct inode *dir, struct dentry *dentry)
{
int err = vfs_whiteout(ovl_upper_mnt_userns(ofs), dir, dentry);
pr_debug("whiteout(%pd2) = %i\n", dentry, err);
return err;
}
static inline struct file *ovl_do_tmpfile(struct ovl_fs *ofs,
struct dentry *dentry, umode_t mode)
{
struct path path = { .mnt = ovl_upper_mnt(ofs), .dentry = dentry };
struct file *file = vfs_tmpfile_open(ovl_upper_mnt_userns(ofs), &path, mode,
O_LARGEFILE | O_WRONLY, current_cred());
int err = PTR_ERR_OR_ZERO(file);
pr_debug("tmpfile(%pd2, 0%o) = %i\n", dentry, mode, err);
return file;
}
static inline struct dentry *ovl_lookup_upper(struct ovl_fs *ofs,
const char *name,
struct dentry *base, int len)
{
return lookup_one(ovl_upper_mnt_userns(ofs), name, base, len);
}
static inline bool ovl_open_flags_need_copy_up(int flags)
{
if (!flags)
return false;
return ((OPEN_FMODE(flags) & FMODE_WRITE) || (flags & O_TRUNC));
}
static inline bool ovl_allow_offline_changes(struct ovl_fs *ofs)
{
/*
* To avoid regressions in existing setups with overlay lower offline
* changes, we allow lower changes only if none of the new features
* are used.
*/
return (!ofs->config.index && !ofs->config.metacopy &&
!ofs->config.redirect_dir && ofs->config.xino != OVL_XINO_ON);
}
/* util.c */
int ovl_want_write(struct dentry *dentry);
void ovl_drop_write(struct dentry *dentry);
struct dentry *ovl_workdir(struct dentry *dentry);
const struct cred *ovl_override_creds(struct super_block *sb);
int ovl_can_decode_fh(struct super_block *sb);
struct dentry *ovl_indexdir(struct super_block *sb);
bool ovl_index_all(struct super_block *sb);
bool ovl_verify_lower(struct super_block *sb);
struct ovl_entry *ovl_alloc_entry(unsigned int numlower);
bool ovl_dentry_remote(struct dentry *dentry);
void ovl_dentry_update_reval(struct dentry *dentry, struct dentry *upperdentry,
unsigned int mask);
bool ovl_dentry_weird(struct dentry *dentry);
enum ovl_path_type ovl_path_type(struct dentry *dentry);
void ovl_path_upper(struct dentry *dentry, struct path *path);
void ovl_path_lower(struct dentry *dentry, struct path *path);
void ovl_path_lowerdata(struct dentry *dentry, struct path *path);
void ovl_i_path_real(struct inode *inode, struct path *path);
enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path);
enum ovl_path_type ovl_path_realdata(struct dentry *dentry, struct path *path);
struct dentry *ovl_dentry_upper(struct dentry *dentry);
struct dentry *ovl_dentry_lower(struct dentry *dentry);
struct dentry *ovl_dentry_lowerdata(struct dentry *dentry);
const struct ovl_layer *ovl_i_layer_lower(struct inode *inode);
const struct ovl_layer *ovl_layer_lower(struct dentry *dentry);
struct dentry *ovl_dentry_real(struct dentry *dentry);
struct dentry *ovl_i_dentry_upper(struct inode *inode);
struct inode *ovl_inode_upper(struct inode *inode);
struct inode *ovl_inode_lower(struct inode *inode);
struct inode *ovl_inode_lowerdata(struct inode *inode);
struct inode *ovl_inode_real(struct inode *inode);
struct inode *ovl_inode_realdata(struct inode *inode);
struct ovl_dir_cache *ovl_dir_cache(struct inode *inode);
void ovl_set_dir_cache(struct inode *inode, struct ovl_dir_cache *cache);
void ovl_dentry_set_flag(unsigned long flag, struct dentry *dentry);
void ovl_dentry_clear_flag(unsigned long flag, struct dentry *dentry);
bool ovl_dentry_test_flag(unsigned long flag, struct dentry *dentry);
bool ovl_dentry_is_opaque(struct dentry *dentry);
bool ovl_dentry_is_whiteout(struct dentry *dentry);
void ovl_dentry_set_opaque(struct dentry *dentry);
bool ovl_dentry_has_upper_alias(struct dentry *dentry);
void ovl_dentry_set_upper_alias(struct dentry *dentry);
bool ovl_dentry_needs_data_copy_up(struct dentry *dentry, int flags);
bool ovl_dentry_needs_data_copy_up_locked(struct dentry *dentry, int flags);
bool ovl_has_upperdata(struct inode *inode);
void ovl_set_upperdata(struct inode *inode);
bool ovl_redirect_dir(struct super_block *sb);
const char *ovl_dentry_get_redirect(struct dentry *dentry);
void ovl_dentry_set_redirect(struct dentry *dentry, const char *redirect);
void ovl_inode_update(struct inode *inode, struct dentry *upperdentry);
void ovl_dir_modified(struct dentry *dentry, bool impurity);
u64 ovl_dentry_version_get(struct dentry *dentry);
bool ovl_is_whiteout(struct dentry *dentry);
struct file *ovl_path_open(const struct path *path, int flags);
int ovl_copy_up_start(struct dentry *dentry, int flags);
void ovl_copy_up_end(struct dentry *dentry);
bool ovl_already_copied_up(struct dentry *dentry, int flags);
bool ovl_path_check_dir_xattr(struct ovl_fs *ofs, const struct path *path,
enum ovl_xattr ox);
bool ovl_path_check_origin_xattr(struct ovl_fs *ofs, const struct path *path);
static inline bool ovl_check_origin_xattr(struct ovl_fs *ofs,
struct dentry *upperdentry)
{
struct path upperpath = {
.dentry = upperdentry,
.mnt = ovl_upper_mnt(ofs),
};
return ovl_path_check_origin_xattr(ofs, &upperpath);
}
int ovl_check_setxattr(struct ovl_fs *ofs, struct dentry *upperdentry,
enum ovl_xattr ox, const void *value, size_t size,
int xerr);
int ovl_set_impure(struct dentry *dentry, struct dentry *upperdentry);
bool ovl_inuse_trylock(struct dentry *dentry);
void ovl_inuse_unlock(struct dentry *dentry);
bool ovl_is_inuse(struct dentry *dentry);
bool ovl_need_index(struct dentry *dentry);
int ovl_nlink_start(struct dentry *dentry);
void ovl_nlink_end(struct dentry *dentry);
int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir);
int ovl_check_metacopy_xattr(struct ovl_fs *ofs, const struct path *path);
bool ovl_is_metacopy_dentry(struct dentry *dentry);
char *ovl_get_redirect_xattr(struct ovl_fs *ofs, const struct path *path, int padding);
int ovl_sync_status(struct ovl_fs *ofs);
static inline void ovl_set_flag(unsigned long flag, struct inode *inode)
{
set_bit(flag, &OVL_I(inode)->flags);
}
static inline void ovl_clear_flag(unsigned long flag, struct inode *inode)
{
clear_bit(flag, &OVL_I(inode)->flags);
}
static inline bool ovl_test_flag(unsigned long flag, struct inode *inode)
{
return test_bit(flag, &OVL_I(inode)->flags);
}
static inline bool ovl_is_impuredir(struct super_block *sb,
struct dentry *upperdentry)
{
struct ovl_fs *ofs = OVL_FS(sb);
struct path upperpath = {
.dentry = upperdentry,
.mnt = ovl_upper_mnt(ofs),
};
return ovl_path_check_dir_xattr(ofs, &upperpath, OVL_XATTR_IMPURE);
}
/*
* With xino=auto, we do best effort to keep all inodes on same st_dev and
* d_ino consistent with st_ino.
* With xino=on, we do the same effort but we warn if we failed.
*/
static inline bool ovl_xino_warn(struct super_block *sb)
{
return OVL_FS(sb)->config.xino == OVL_XINO_ON;
}
/* All layers on same fs? */
static inline bool ovl_same_fs(struct super_block *sb)
{
return OVL_FS(sb)->xino_mode == 0;
}
/* All overlay inodes have same st_dev? */
static inline bool ovl_same_dev(struct super_block *sb)
{
return OVL_FS(sb)->xino_mode >= 0;
}
static inline unsigned int ovl_xino_bits(struct super_block *sb)
{
return ovl_same_dev(sb) ? OVL_FS(sb)->xino_mode : 0;
}
static inline void ovl_inode_lock(struct inode *inode)
{
mutex_lock(&OVL_I(inode)->lock);
}
static inline int ovl_inode_lock_interruptible(struct inode *inode)
{
return mutex_lock_interruptible(&OVL_I(inode)->lock);
}
static inline void ovl_inode_unlock(struct inode *inode)
{
mutex_unlock(&OVL_I(inode)->lock);
}
/* namei.c */
int ovl_check_fb_len(struct ovl_fb *fb, int fb_len);
static inline int ovl_check_fh_len(struct ovl_fh *fh, int fh_len)
{
if (fh_len < sizeof(struct ovl_fh))
return -EINVAL;
return ovl_check_fb_len(&fh->fb, fh_len - OVL_FH_WIRE_OFFSET);
}
struct dentry *ovl_decode_real_fh(struct ovl_fs *ofs, struct ovl_fh *fh,
struct vfsmount *mnt, bool connected);
int ovl_check_origin_fh(struct ovl_fs *ofs, struct ovl_fh *fh, bool connected,
struct dentry *upperdentry, struct ovl_path **stackp);
int ovl_verify_set_fh(struct ovl_fs *ofs, struct dentry *dentry,
enum ovl_xattr ox, struct dentry *real, bool is_upper,
bool set);
struct dentry *ovl_index_upper(struct ovl_fs *ofs, struct dentry *index);
int ovl_verify_index(struct ovl_fs *ofs, struct dentry *index);
int ovl_get_index_name(struct ovl_fs *ofs, struct dentry *origin,
struct qstr *name);
struct dentry *ovl_get_index_fh(struct ovl_fs *ofs, struct ovl_fh *fh);
struct dentry *ovl_lookup_index(struct ovl_fs *ofs, struct dentry *upper,
struct dentry *origin, bool verify);
int ovl_path_next(int idx, struct dentry *dentry, struct path *path);
struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
unsigned int flags);
bool ovl_lower_positive(struct dentry *dentry);
static inline int ovl_verify_origin(struct ovl_fs *ofs, struct dentry *upper,
struct dentry *origin, bool set)
{
return ovl_verify_set_fh(ofs, upper, OVL_XATTR_ORIGIN, origin,
false, set);
}
static inline int ovl_verify_upper(struct ovl_fs *ofs, struct dentry *index,
struct dentry *upper, bool set)
{
return ovl_verify_set_fh(ofs, index, OVL_XATTR_UPPER, upper, true, set);
}
/* readdir.c */
extern const struct file_operations ovl_dir_operations;
struct file *ovl_dir_real_file(const struct file *file, bool want_upper);
int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list);
void ovl_cleanup_whiteouts(struct ovl_fs *ofs, struct dentry *upper,
struct list_head *list);
void ovl_cache_free(struct list_head *list);
void ovl_dir_cache_free(struct inode *inode);
int ovl_check_d_type_supported(const struct path *realpath);
int ovl_workdir_cleanup(struct ovl_fs *ofs, struct inode *dir,
struct vfsmount *mnt, struct dentry *dentry, int level);
int ovl_indexdir_cleanup(struct ovl_fs *ofs);
/*
* Can we iterate real dir directly?
*
* Non-merge dir may contain whiteouts from a time it was a merge upper, before
* lower dir was removed under it and possibly before it was rotated from upper
* to lower layer.
*/
static inline bool ovl_dir_is_real(struct dentry *dir)
{
return !ovl_test_flag(OVL_WHITEOUTS, d_inode(dir));
}
/* inode.c */
int ovl_set_nlink_upper(struct dentry *dentry);
int ovl_set_nlink_lower(struct dentry *dentry);
unsigned int ovl_get_nlink(struct ovl_fs *ofs, struct dentry *lowerdentry,
struct dentry *upperdentry,
unsigned int fallback);
int ovl_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
struct iattr *attr);
int ovl_getattr(struct user_namespace *mnt_userns, const struct path *path,
struct kstat *stat, u32 request_mask, unsigned int flags);
int ovl_permission(struct user_namespace *mnt_userns, struct inode *inode,
int mask);
int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
const void *value, size_t size, int flags);
int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name,
void *value, size_t size);
ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size);
#ifdef CONFIG_FS_POSIX_ACL
struct posix_acl *ovl_get_acl(struct inode *inode, int type, bool rcu);
#else
#define ovl_get_acl NULL
#endif
int ovl_update_time(struct inode *inode, struct timespec64 *ts, int flags);
bool ovl_is_private_xattr(struct super_block *sb, const char *name);
struct ovl_inode_params {
struct inode *newinode;
struct dentry *upperdentry;
struct ovl_path *lowerpath;
bool index;
unsigned int numlower;
char *redirect;
struct dentry *lowerdata;
};
void ovl_inode_init(struct inode *inode, struct ovl_inode_params *oip,
unsigned long ino, int fsid);
struct inode *ovl_new_inode(struct super_block *sb, umode_t mode, dev_t rdev);
struct inode *ovl_lookup_inode(struct super_block *sb, struct dentry *real,
bool is_upper);
bool ovl_lookup_trap_inode(struct super_block *sb, struct dentry *dir);
struct inode *ovl_get_trap_inode(struct super_block *sb, struct dentry *dir);
struct inode *ovl_get_inode(struct super_block *sb,
struct ovl_inode_params *oip);
void ovl_copyattr(struct inode *to);
/* vfs inode flags copied from real to ovl inode */
#define OVL_COPY_I_FLAGS_MASK (S_SYNC | S_NOATIME | S_APPEND | S_IMMUTABLE)
/* vfs inode flags read from overlay.protattr xattr to ovl inode */
#define OVL_PROT_I_FLAGS_MASK (S_APPEND | S_IMMUTABLE)
/*
* fileattr flags copied from lower to upper inode on copy up.
* We cannot copy up immutable/append-only flags, because that would prevent
* linking temp inode to upper dir, so we store them in xattr instead.
*/
#define OVL_COPY_FS_FLAGS_MASK (FS_SYNC_FL | FS_NOATIME_FL)
#define OVL_COPY_FSX_FLAGS_MASK (FS_XFLAG_SYNC | FS_XFLAG_NOATIME)
#define OVL_PROT_FS_FLAGS_MASK (FS_APPEND_FL | FS_IMMUTABLE_FL)
#define OVL_PROT_FSX_FLAGS_MASK (FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE)
void ovl_check_protattr(struct inode *inode, struct dentry *upper);
int ovl_set_protattr(struct inode *inode, struct dentry *upper,
struct fileattr *fa);
static inline void ovl_copyflags(struct inode *from, struct inode *to)
{
unsigned int mask = OVL_COPY_I_FLAGS_MASK;
inode_set_flags(to, from->i_flags & mask, mask);
}
/* dir.c */
extern const struct inode_operations ovl_dir_inode_operations;
int ovl_cleanup_and_whiteout(struct ovl_fs *ofs, struct inode *dir,
struct dentry *dentry);
struct ovl_cattr {
dev_t rdev;
umode_t mode;
const char *link;
struct dentry *hardlink;
};
#define OVL_CATTR(m) (&(struct ovl_cattr) { .mode = (m) })
int ovl_mkdir_real(struct ovl_fs *ofs, struct inode *dir,
struct dentry **newdentry, umode_t mode);
struct dentry *ovl_create_real(struct ovl_fs *ofs,
struct inode *dir, struct dentry *newdentry,
struct ovl_cattr *attr);
int ovl_cleanup(struct ovl_fs *ofs, struct inode *dir, struct dentry *dentry);
struct dentry *ovl_lookup_temp(struct ovl_fs *ofs, struct dentry *workdir);
struct dentry *ovl_create_temp(struct ovl_fs *ofs, struct dentry *workdir,
struct ovl_cattr *attr);
/* file.c */
extern const struct file_operations ovl_file_operations;
int __init ovl_aio_request_cache_init(void);
void ovl_aio_request_cache_destroy(void);
int ovl_real_fileattr_get(const struct path *realpath, struct fileattr *fa);
int ovl_real_fileattr_set(const struct path *realpath, struct fileattr *fa);
int ovl_fileattr_get(struct dentry *dentry, struct fileattr *fa);
int ovl_fileattr_set(struct user_namespace *mnt_userns,
struct dentry *dentry, struct fileattr *fa);
/* copy_up.c */
int ovl_copy_up(struct dentry *dentry);
int ovl_copy_up_with_data(struct dentry *dentry);
int ovl_maybe_copy_up(struct dentry *dentry, int flags);
int ovl_copy_xattr(struct super_block *sb, const struct path *path, struct dentry *new);
int ovl_set_attr(struct ovl_fs *ofs, struct dentry *upper, struct kstat *stat);
struct ovl_fh *ovl_encode_real_fh(struct ovl_fs *ofs, struct dentry *real,
bool is_upper);
int ovl_set_origin(struct ovl_fs *ofs, struct dentry *lower,
struct dentry *upper);
/* export.c */
extern const struct export_operations ovl_export_operations;
Reference in New Issue View Git Blame Copy Permalink