static int __init aufs_init(void)
{
int err, i;
char *p;
p = au_esc_chars;
for (i = 1; i <= ' '; i++)
*p++ = i;
*p++ = '\\';
*p++ = '\x7f';
*p = 0;
au_dir_roflags = au_file_roflags(O_DIRECTORY | O_LARGEFILE);
au_sbilist_init();
sysaufs_brs_init();
au_debug_init();
au_dy_init();
err = sysaufs_init();
if (unlikely(err))
goto out;
err = au_procfs_init();
if (unlikely(err))
goto out_sysaufs;
err = au_wkq_init();
if (unlikely(err))
goto out_procfs;
err = au_hnotify_init();
if (unlikely(err))
goto out_wkq;
err = au_sysrq_init();
if (unlikely(err))
goto out_hin;
err = au_cache_init();
if (unlikely(err))
goto out_sysrq;
err = register_filesystem(&aufs_fs_type);
if (unlikely(err))
goto out_cache;
/* since we define pr_fmt, call printk directly */
printk(KERN_INFO AUFS_NAME " " AUFS_VERSION "\n");
goto out; /* success */
out_cache:
au_cache_fin();
out_sysrq:
au_sysrq_fin();
out_hin:
au_hnotify_fin();
out_wkq:
au_wkq_fin();
out_procfs:
au_procfs_fin();
out_sysaufs:
sysaufs_fin();
au_dy_fin();
out:
return err;
}
/* common functions to regular file and dir */
struct file *hidden_open(struct dentry *dentry, aufs_bindex_t bindex, int flags)
{
struct dentry *hidden_dentry;
struct inode *hidden_inode;
struct super_block *sb;
struct vfsmount *hidden_mnt;
struct file *hidden_file;
struct aufs_branch *br;
loff_t old_size;
int udba;
LKTRTrace("%.*s, b%d, flags 0%o\n", DLNPair(dentry), bindex, flags);
DEBUG_ON(!dentry);
hidden_dentry = au_h_dptr_i(dentry, bindex);
DEBUG_ON(!hidden_dentry);
hidden_inode = hidden_dentry->d_inode;
DEBUG_ON(!hidden_inode);
sb = dentry->d_sb;
udba = au_flag_test(sb, AuFlag_UDBA_INOTIFY);
if (unlikely(udba)) {
// test here?
}
br = stobr(sb, bindex);
br_get(br);
/* drop flags for writing */
if (test_ro(sb, bindex, dentry->d_inode))
flags = au_file_roflags(flags);
flags &= ~O_CREAT;
spin_lock(&hidden_inode->i_lock);
old_size = i_size_read(hidden_inode);
spin_unlock(&hidden_inode->i_lock);
//DbgSleep(3);
dget(hidden_dentry);
hidden_mnt = mntget(br->br_mnt);
hidden_file = dentry_open(hidden_dentry, hidden_mnt, flags);
//if (LktrCond) {fput(hidden_file); hidden_file = ERR_PTR(-1);}
if (!IS_ERR(hidden_file)) {
#if 0 // remove this
if (/* old_size && */ (flags & O_TRUNC)) {
au_direval_dec(dentry);
if (!IS_ROOT(dentry))
au_direval_dec(dentry->d_parent);
}
#endif
return hidden_file;
}
br_put(br);
TraceErrPtr(hidden_file);
return hidden_file;
}
/* common functions to regular file and dir */
struct file *au_h_open(struct dentry *dentry, aufs_bindex_t bindex, int flags,
struct file *file)
{
struct file *h_file;
struct dentry *h_dentry;
struct inode *h_inode;
struct super_block *sb;
struct au_branch *br;
struct path h_path;
int err, exec_flag;
/* a race condition can happen between open and unlink/rmdir */
h_file = ERR_PTR(-ENOENT);
h_dentry = au_h_dptr(dentry, bindex);
if (au_test_nfsd() && !h_dentry)
goto out;
h_inode = h_dentry->d_inode;
if (au_test_nfsd() && !h_inode)
goto out;
spin_lock(&h_dentry->d_lock);
err = (!d_unhashed(dentry) && d_unlinked(h_dentry))
|| !h_inode
/* || !dentry->d_inode->i_nlink */
;
spin_unlock(&h_dentry->d_lock);
if (unlikely(err))
goto out;
sb = dentry->d_sb;
br = au_sbr(sb, bindex);
h_file = ERR_PTR(-EACCES);
exec_flag = flags & __FMODE_EXEC;
if (exec_flag && (br->br_mnt->mnt_flags & MNT_NOEXEC))
goto out;
/* drop flags for writing */
if (au_test_ro(sb, bindex, dentry->d_inode))
flags = au_file_roflags(flags);
flags &= ~O_CREAT;
atomic_inc(&br->br_count);
h_path.dentry = h_dentry;
h_path.mnt = br->br_mnt;
if (!au_special_file(h_inode->i_mode))
h_file = vfsub_dentry_open(&h_path, flags);
else {
/* this block depends upon the configuration */
di_read_unlock(dentry, AuLock_IR);
fi_write_unlock(file);
si_read_unlock(sb);
h_file = vfsub_dentry_open(&h_path, flags);
si_noflush_read_lock(sb);
fi_write_lock(file);
di_read_lock_child(dentry, AuLock_IR);
}
if (IS_ERR(h_file))
goto out_br;
if (exec_flag) {
err = deny_write_access(h_file);
if (unlikely(err)) {
fput(h_file);
h_file = ERR_PTR(err);
goto out_br;
}
}
fsnotify_open(h_file);
goto out; /* success */
out_br:
atomic_dec(&br->br_count);
out:
return h_file;
}
static int __init aufs_init(void)
{
int err, i;
char *p;
au_debug_init();
#ifdef CONFIG_AUFS_INO_T_64
BUILD_BUG_ON(sizeof(ino_t) != sizeof(long long));
#else
BUILD_BUG_ON(sizeof(ino_t) != sizeof(int));
#endif
p = au_esc_chars;
for (i = 1; i <= ' '; i++)
*p++ = i;
*p++ = '\\';
*p++ = '\x7f';
*p = 0;
au_dir_roflags = au_file_roflags(O_DIRECTORY | O_LARGEFILE);
err = -EINVAL;
if (unlikely(aufs_nwkq <= 0))
goto out;
err = sysaufs_init();
if (unlikely(err))
goto out;
err = au_wkq_init();
if (unlikely(err))
goto out_sysaufs;
err = au_inotify_init();
if (unlikely(err))
goto out_wkq;
err = au_sysrq_init();
if (unlikely(err))
goto out_inotify;
err = create_cache();
if (unlikely(err))
goto out_sysrq;
err = register_filesystem(&aufs_fs_type);
if (unlikely(err))
goto out_cache;
pr_info(AUFS_NAME " " AUFS_VERSION "\n");
return 0; /* success */
out_cache:
destroy_cache();
out_sysrq:
au_sysrq_fin();
out_inotify:
au_inotify_fin();
out_wkq:
au_wkq_fin();
out_sysaufs:
sysaufs_fin();
out:
AuTraceErr(err);
return err;
}
/* common functions to regular file and dir */
struct file *au_h_open(struct dentry *dentry, aufs_bindex_t bindex, int flags,
struct file *file, int force_wr)
{
struct file *h_file;
struct dentry *h_dentry;
struct inode *h_inode;
struct super_block *sb;
struct au_branch *br;
struct path h_path;
int err, exec_flag;
/* a race condition can happen between open and unlink/rmdir */
h_file = ERR_PTR(-ENOENT);
h_dentry = au_h_dptr(dentry, bindex);
if (au_test_nfsd() && !h_dentry)
goto out;
h_inode = h_dentry->d_inode;
if (au_test_nfsd() && !h_inode)
goto out;
spin_lock(&h_dentry->d_lock);
err = (!d_unhashed(dentry) && d_unlinked(h_dentry))
|| !h_inode
/* || !dentry->d_inode->i_nlink */
;
spin_unlock(&h_dentry->d_lock);
if (unlikely(err))
goto out;
sb = dentry->d_sb;
br = au_sbr(sb, bindex);
h_file = ERR_PTR(-EACCES);
exec_flag = flags & __FMODE_EXEC;
if (exec_flag && (au_br_mnt(br)->mnt_flags & MNT_NOEXEC))
goto out;
/* drop flags for writing */
if (au_test_ro(sb, bindex, dentry->d_inode)) {
if (force_wr && !(flags & O_WRONLY))
force_wr = 0;
flags = au_file_roflags(flags);
if (force_wr) {
h_file = ERR_PTR(-EROFS);
flags = au_file_roflags(flags);
if (unlikely(vfsub_native_ro(h_inode)
|| IS_APPEND(h_inode)))
goto out;
flags &= ~O_ACCMODE;
flags |= O_WRONLY;
}
}
flags &= ~O_CREAT;
atomic_inc(&br->br_count);
h_path.dentry = h_dentry;
h_path.mnt = au_br_mnt(br);
h_file = vfsub_dentry_open(&h_path, flags);
if (IS_ERR(h_file))
goto out_br;
if (exec_flag) {
err = deny_write_access(h_file);
if (unlikely(err)) {
fput(h_file);
h_file = ERR_PTR(err);
goto out_br;
}
}
fsnotify_open(h_file);
goto out; /* success */
out_br:
atomic_dec(&br->br_count);
out:
return h_file;
}