mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-28 15:13:55 +08:00
b8e42a651b
ofs->upper_mnt is copied to ->layers[0].mnt and ->layers[0].trap could be used instead of a separate ->upperdir_trap. Split the lowerdir option early to get the number of layers, then allocate the ->layers array, and finally fill the upper and lower layers, as before. Get rid of path_put_init() in ovl_lower_dir(), since the only caller will take care of that. [Colin Ian King] Fix null pointer dereference on null stack pointer on error return found by Coverity. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
137 lines
3.1 KiB
C
137 lines
3.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
*
|
|
* Copyright (C) 2011 Novell Inc.
|
|
* Copyright (C) 2016 Red Hat, Inc.
|
|
*/
|
|
|
|
struct ovl_config {
|
|
char *lowerdir;
|
|
char *upperdir;
|
|
char *workdir;
|
|
bool default_permissions;
|
|
bool redirect_dir;
|
|
bool redirect_follow;
|
|
const char *redirect_mode;
|
|
bool index;
|
|
bool nfs_export;
|
|
int xino;
|
|
bool metacopy;
|
|
};
|
|
|
|
struct ovl_sb {
|
|
struct super_block *sb;
|
|
dev_t pseudo_dev;
|
|
/* Unusable (conflicting) uuid */
|
|
bool bad_uuid;
|
|
/* Used as a lower layer (but maybe also as upper) */
|
|
bool is_lower;
|
|
};
|
|
|
|
struct ovl_layer {
|
|
struct vfsmount *mnt;
|
|
/* Trap in ovl inode cache */
|
|
struct inode *trap;
|
|
struct ovl_sb *fs;
|
|
/* Index of this layer in fs root (upper idx == 0) */
|
|
int idx;
|
|
/* One fsid per unique underlying sb (upper fsid == 0) */
|
|
int fsid;
|
|
};
|
|
|
|
struct ovl_path {
|
|
const struct ovl_layer *layer;
|
|
struct dentry *dentry;
|
|
};
|
|
|
|
/* private information held for overlayfs's superblock */
|
|
struct ovl_fs {
|
|
unsigned int numlayer;
|
|
/* Number of unique fs among layers including upper fs */
|
|
unsigned int numfs;
|
|
const struct ovl_layer *layers;
|
|
struct ovl_sb *fs;
|
|
/* workbasedir is the path at workdir= mount option */
|
|
struct dentry *workbasedir;
|
|
/* workdir is the 'work' directory under workbasedir */
|
|
struct dentry *workdir;
|
|
/* index directory listing overlay inodes by origin file handle */
|
|
struct dentry *indexdir;
|
|
long namelen;
|
|
/* pathnames of lower and upper dirs, for show_options */
|
|
struct ovl_config config;
|
|
/* creds of process who forced instantiation of super block */
|
|
const struct cred *creator_cred;
|
|
bool tmpfile;
|
|
bool noxattr;
|
|
/* Did we take the inuse lock? */
|
|
bool upperdir_locked;
|
|
bool workdir_locked;
|
|
bool share_whiteout;
|
|
/* Traps in ovl inode cache */
|
|
struct inode *workbasedir_trap;
|
|
struct inode *workdir_trap;
|
|
struct inode *indexdir_trap;
|
|
/* -1: disabled, 0: same fs, 1..32: number of unused ino bits */
|
|
int xino_mode;
|
|
/* For allocation of non-persistent inode numbers */
|
|
atomic_long_t last_ino;
|
|
/* Whiteout dentry cache */
|
|
struct dentry *whiteout;
|
|
};
|
|
|
|
static inline struct vfsmount *ovl_upper_mnt(struct ovl_fs *ofs)
|
|
{
|
|
return ofs->layers[0].mnt;
|
|
}
|
|
|
|
static inline struct ovl_fs *OVL_FS(struct super_block *sb)
|
|
{
|
|
return (struct ovl_fs *)sb->s_fs_info;
|
|
}
|
|
|
|
/* private information held for every overlayfs dentry */
|
|
struct ovl_entry {
|
|
union {
|
|
struct {
|
|
unsigned long flags;
|
|
};
|
|
struct rcu_head rcu;
|
|
};
|
|
unsigned numlower;
|
|
struct ovl_path lowerstack[];
|
|
};
|
|
|
|
struct ovl_entry *ovl_alloc_entry(unsigned int numlower);
|
|
|
|
static inline struct ovl_entry *OVL_E(struct dentry *dentry)
|
|
{
|
|
return (struct ovl_entry *) dentry->d_fsdata;
|
|
}
|
|
|
|
struct ovl_inode {
|
|
union {
|
|
struct ovl_dir_cache *cache; /* directory */
|
|
struct inode *lowerdata; /* regular file */
|
|
};
|
|
const char *redirect;
|
|
u64 version;
|
|
unsigned long flags;
|
|
struct inode vfs_inode;
|
|
struct dentry *__upperdentry;
|
|
struct inode *lower;
|
|
|
|
/* synchronize copy up and more */
|
|
struct mutex lock;
|
|
};
|
|
|
|
static inline struct ovl_inode *OVL_I(struct inode *inode)
|
|
{
|
|
return container_of(inode, struct ovl_inode, vfs_inode);
|
|
}
|
|
|
|
static inline struct dentry *ovl_upperdentry_dereference(struct ovl_inode *oi)
|
|
{
|
|
return READ_ONCE(oi->__upperdentry);
|
|
}
|