int aufs_rename(struct inode *_src_dir, struct dentry *_src_dentry,
struct inode *_dst_dir, struct dentry *_dst_dentry)
{
int err, flags;
/* reduce stack space */
struct au_ren_args *a;
AuDbg("%.*s, %.*s\n", AuDLNPair(_src_dentry), AuDLNPair(_dst_dentry));
IMustLock(_src_dir);
IMustLock(_dst_dir);
err = -ENOMEM;
BUILD_BUG_ON(sizeof(*a) > PAGE_SIZE);
a = kzalloc(sizeof(*a), GFP_NOFS);
if (unlikely(!a))
goto out;
a->src_dir = _src_dir;
a->src_dentry = _src_dentry;
a->src_inode = a->src_dentry->d_inode;
a->src_parent = a->src_dentry->d_parent; /* dir inode is locked */
a->dst_dir = _dst_dir;
a->dst_dentry = _dst_dentry;
a->dst_inode = a->dst_dentry->d_inode;
a->dst_parent = a->dst_dentry->d_parent; /* dir inode is locked */
if (a->dst_inode) {
IMustLock(a->dst_inode);
au_igrab(a->dst_inode);
}
err = -ENOTDIR;
flags = AuLock_FLUSH | AuLock_NOPLM | AuLock_GEN;
if (S_ISDIR(a->src_inode->i_mode)) {
au_fset_ren(a->flags, ISDIR);
if (unlikely(a->dst_inode && !S_ISDIR(a->dst_inode->i_mode)))
goto out_free;
err = aufs_read_and_write_lock2(a->dst_dentry, a->src_dentry,
AuLock_DIR | flags);
} else
err = aufs_read_and_write_lock2(a->dst_dentry, a->src_dentry,
flags);
if (unlikely(err))
goto out_free;
err = au_d_hashed_positive(a->src_dentry);
if (unlikely(err))
goto out_unlock;
err = -ENOENT;
if (a->dst_inode) {
/*
* If it is a dir, VFS unhash dst_dentry before this
* function. It means we cannot rely upon d_unhashed().
*/
if (unlikely(!a->dst_inode->i_nlink))
goto out_unlock;
if (!S_ISDIR(a->dst_inode->i_mode)) {
err = au_d_hashed_positive(a->dst_dentry);
if (unlikely(err))
goto out_unlock;
} else if (unlikely(IS_DEADDIR(a->dst_inode)))
goto out_unlock;
} else if (unlikely(d_unhashed(a->dst_dentry)))
goto out_unlock;
au_fset_ren(a->flags, ISSAMEDIR); /* temporary */
di_write_lock_parent(a->dst_parent);
/* which branch we process */
err = au_ren_wbr(a);
if (unlikely(err < 0))
goto out_parent;
a->br = au_sbr(a->dst_dentry->d_sb, a->btgt);
a->h_path.mnt = a->br->br_mnt;
/* are they available to be renamed */
err = au_ren_may_dir(a);
if (unlikely(err))
goto out_children;
/* prepare the writable parent dir on the same branch */
if (a->dst_bstart == a->btgt) {
au_fset_ren(a->flags, WHDST);
} else {
err = au_cpup_dirs(a->dst_dentry, a->btgt);
if (unlikely(err))
goto out_children;
}
if (a->src_dir != a->dst_dir) {
/*
* this temporary unlock is safe,
* because both dir->i_mutex are locked.
*/
di_write_unlock(a->dst_parent);
di_write_lock_parent(a->src_parent);
err = au_wr_dir_need_wh(a->src_dentry,
au_ftest_ren(a->flags, ISDIR),
&a->btgt);
di_write_unlock(a->src_parent);
di_write_lock2_parent(a->src_parent, a->dst_parent, /*isdir*/1);
au_fclr_ren(a->flags, ISSAMEDIR);
} else
err = au_wr_dir_need_wh(a->src_dentry,
au_ftest_ren(a->flags, ISDIR),
&a->btgt);
if (unlikely(err < 0))
goto out_children;
if (err)
au_fset_ren(a->flags, WHSRC);
/* lock them all */
err = au_ren_lock(a);
if (unlikely(err))
goto out_children;
if (!au_opt_test(au_mntflags(a->dst_dir->i_sb), UDBA_NONE))
err = au_may_ren(a);
else if (unlikely(a->dst_dentry->d_name.len > AUFS_MAX_NAMELEN))
err = -ENAMETOOLONG;
if (unlikely(err))
goto out_hdir;
/* store timestamps to be revertible */
au_ren_dt(a);
/* here we go */
err = do_rename(a);
if (unlikely(err))
goto out_dt;
/* update dir attributes */
au_ren_refresh_dir(a);
/* dput/iput all lower dentries */
au_ren_refresh(a);
goto out_hdir; /* success */
out_dt:
au_ren_rev_dt(err, a);
out_hdir:
au_ren_unlock(a);
out_children:
au_nhash_wh_free(&a->whlist);
if (err && a->dst_inode && a->dst_bstart != a->btgt) {
AuDbg("bstart %d, btgt %d\n", a->dst_bstart, a->btgt);
au_set_h_dptr(a->dst_dentry, a->btgt, NULL);
au_set_dbstart(a->dst_dentry, a->dst_bstart);
}
out_parent:
if (!err)
d_move(a->src_dentry, a->dst_dentry);
else {
au_update_dbstart(a->dst_dentry);
if (!a->dst_inode)
d_drop(a->dst_dentry);
}
if (au_ftest_ren(a->flags, ISSAMEDIR))
di_write_unlock(a->dst_parent);
else
di_write_unlock2(a->src_parent, a->dst_parent);
out_unlock:
aufs_read_and_write_unlock2(a->dst_dentry, a->src_dentry);
out_free:
iput(a->dst_inode);
if (a->thargs)
au_whtmp_rmdir_free(a->thargs);
kfree(a);
out:
AuTraceErr(err);
return err;
}
int aufs_rmdir(struct inode *dir, struct dentry *dentry)
{
int err, rmdir_later;
aufs_bindex_t bwh, bindex, bstart;
struct au_dtime dt;
struct au_pin pin;
struct inode *inode;
struct dentry *parent, *wh_dentry, *h_dentry;
struct au_whtmp_rmdir *args;
IMustLock(dir);
err = aufs_read_lock(dentry, AuLock_DW | AuLock_FLUSH | AuLock_GEN);
if (unlikely(err))
goto out;
err = au_alive_dir(dentry);
if (unlikely(err))
goto out_unlock;
inode = dentry->d_inode;
IMustLock(inode);
err = -ENOTDIR;
if (unlikely(!S_ISDIR(inode->i_mode)))
goto out_unlock; /* possible? */
err = -ENOMEM;
args = au_whtmp_rmdir_alloc(dir->i_sb, GFP_NOFS);
if (unlikely(!args))
goto out_unlock;
parent = dentry->d_parent; /* dir inode is locked */
di_write_lock_parent(parent);
err = au_test_empty(dentry, &args->whlist);
if (unlikely(err))
goto out_parent;
bstart = au_dbstart(dentry);
bwh = au_dbwh(dentry);
bindex = -1;
wh_dentry = lock_hdir_create_wh(dentry, /*isdir*/1, &bindex, &dt, &pin);
err = PTR_ERR(wh_dentry);
if (IS_ERR(wh_dentry))
goto out_parent;
h_dentry = au_h_dptr(dentry, bstart);
dget(h_dentry);
rmdir_later = 0;
if (bindex == bstart) {
err = renwh_and_rmdir(dentry, bstart, &args->whlist, dir);
if (err > 0) {
rmdir_later = err;
err = 0;
}
} else {
/* stop monitoring */
au_hn_free(au_hi(inode, bstart));
/* dir inode is locked */
IMustLock(wh_dentry->d_parent->d_inode);
err = 0;
}
if (!err) {
vfsub_dead_dir(inode);
au_set_dbdiropq(dentry, -1);
epilog(dir, dentry, bindex);
if (rmdir_later) {
au_whtmp_kick_rmdir(dir, bstart, h_dentry, args);
args = NULL;
}
goto out_unpin; /* success */
}
/* revert */
AuLabel(revert);
if (wh_dentry) {
int rerr;
rerr = do_revert(err, dir, bindex, bwh, wh_dentry, dentry, &dt);
if (rerr)
err = rerr;
}
out_unpin:
au_unpin(&pin);
dput(wh_dentry);
dput(h_dentry);
out_parent:
di_write_unlock(parent);
if (args)
au_whtmp_rmdir_free(args);
out_unlock:
aufs_read_unlock(dentry, AuLock_DW);
out:
AuTraceErr(err);
return err;
}
static int do_rename(struct au_ren_args *a)
{
int err;
struct dentry *d, *h_d;
/* prepare workqueue args for asynchronous rmdir */
h_d = a->dst_h_dentry;
if (au_ftest_ren(a->flags, ISDIR) && h_d->d_inode) {
err = -ENOMEM;
a->thargs = au_whtmp_rmdir_alloc(a->src_dentry->d_sb, GFP_NOFS);
if (unlikely(!a->thargs))
goto out;
a->h_dst = dget(h_d);
}
/* create whiteout for src_dentry */
if (au_ftest_ren(a->flags, WHSRC)) {
a->src_bwh = au_dbwh(a->src_dentry);
AuDebugOn(a->src_bwh >= 0);
a->src_wh_dentry
= au_wh_create(a->src_dentry, a->btgt, a->src_h_parent);
err = PTR_ERR(a->src_wh_dentry);
if (IS_ERR(a->src_wh_dentry))
goto out_thargs;
}
/* lookup whiteout for dentry */
if (au_ftest_ren(a->flags, WHDST)) {
h_d = au_wh_lkup(a->dst_h_parent, &a->dst_dentry->d_name,
a->br);
err = PTR_ERR(h_d);
if (IS_ERR(h_d))
goto out_whsrc;
if (!h_d->d_inode)
dput(h_d);
else
a->dst_wh_dentry = h_d;
}
/* rename dentry to tmpwh */
if (a->thargs) {
err = au_whtmp_ren(a->dst_h_dentry, a->br);
if (unlikely(err))
goto out_whdst;
d = a->dst_dentry;
au_set_h_dptr(d, a->btgt, NULL);
err = au_lkup_neg(d, a->btgt);
if (unlikely(err))
goto out_whtmp;
a->dst_h_dentry = au_h_dptr(d, a->btgt);
}
/* cpup src */
if (a->dst_h_dentry->d_inode && a->src_bstart != a->btgt) {
struct mutex *h_mtx = &a->src_h_dentry->d_inode->i_mutex;
struct file *h_file;
mutex_lock_nested(h_mtx, AuLsc_I_CHILD);
AuDebugOn(au_dbstart(a->src_dentry) != a->src_bstart);
h_file = au_h_open_pre(a->src_dentry, a->src_bstart);
if (IS_ERR(h_file)) {
err = PTR_ERR(h_file);
h_file = NULL;
} else
err = au_sio_cpup_simple(a->src_dentry, a->btgt, -1,
!AuCpup_DTIME);
mutex_unlock(h_mtx);
au_h_open_post(a->src_dentry, a->src_bstart, h_file);
if (unlikely(err))
goto out_whtmp;
}
/* rename by vfs_rename or cpup */
d = a->dst_dentry;
if (au_ftest_ren(a->flags, ISDIR)
&& (a->dst_wh_dentry
|| au_dbdiropq(d) == a->btgt
/* hide the lower to keep xino */
|| a->btgt < au_dbend(d)
|| au_opt_test(au_mntflags(d->d_sb), ALWAYS_DIROPQ)))
au_fset_ren(a->flags, DIROPQ);
err = au_ren_or_cpup(a);
if (unlikely(err))
/* leave the copied-up one */
goto out_whtmp;
/* make dir opaque */
if (au_ftest_ren(a->flags, DIROPQ)) {
err = au_ren_diropq(a);
if (unlikely(err))
goto out_rename;
}
/* update target timestamps */
AuDebugOn(au_dbstart(a->src_dentry) != a->btgt);
a->h_path.dentry = au_h_dptr(a->src_dentry, a->btgt);
vfsub_update_h_iattr(&a->h_path, /*did*/NULL); /*ignore*/
a->src_inode->i_ctime = a->h_path.dentry->d_inode->i_ctime;
/* remove whiteout for dentry */
if (a->dst_wh_dentry) {
a->h_path.dentry = a->dst_wh_dentry;
err = au_wh_unlink_dentry(a->dst_h_dir, &a->h_path,
a->dst_dentry);
if (unlikely(err))
goto out_diropq;
}
/* remove whtmp */
if (a->thargs)
au_ren_del_whtmp(a); /* ignore this error */
err = 0;
goto out_success;
out_diropq:
if (au_ftest_ren(a->flags, DIROPQ))
au_ren_rev_diropq(err, a);
out_rename:
if (!au_ftest_ren(a->flags, CPUP))
au_ren_rev_rename(err, a);
else
au_ren_rev_cpup(err, a);
dput(a->h_dst);
out_whtmp:
if (a->thargs)
au_ren_rev_whtmp(err, a);
out_whdst:
dput(a->dst_wh_dentry);
a->dst_wh_dentry = NULL;
out_whsrc:
if (a->src_wh_dentry)
au_ren_rev_whsrc(err, a);
out_success:
dput(a->src_wh_dentry);
dput(a->dst_wh_dentry);
out_thargs:
if (a->thargs) {
dput(a->h_dst);
au_whtmp_rmdir_free(a->thargs);
a->thargs = NULL;
}
out:
return err;
}