/*
* decide the branch where we operate for @dentry. the branch index will be set
* @rbcpup. after diciding it, 'pin' it and store the timestamps of the parent
* dir for reverting.
* when a new whiteout is necessary, create it.
*/
static struct dentry*
lock_hdir_create_wh(struct dentry *dentry, int isdir, aufs_bindex_t *rbcpup,
struct au_dtime *dt, struct au_pin *pin)
{
struct dentry *wh_dentry;
struct super_block *sb;
struct path h_path;
int err, need_wh;
unsigned int udba;
aufs_bindex_t bcpup;
need_wh = au_wr_dir_need_wh(dentry, isdir, rbcpup);
wh_dentry = ERR_PTR(need_wh);
if (unlikely(need_wh < 0))
goto out;
sb = dentry->d_sb;
udba = au_opt_udba(sb);
bcpup = *rbcpup;
err = au_pin(pin, dentry, bcpup, udba,
AuPin_DI_LOCKED | AuPin_MNT_WRITE);
wh_dentry = ERR_PTR(err);
if (unlikely(err))
goto out;
h_path.dentry = au_pinned_h_parent(pin);
if (udba != AuOpt_UDBA_NONE
&& au_dbstart(dentry) == bcpup) {
err = au_may_del(dentry, bcpup, h_path.dentry, isdir);
wh_dentry = ERR_PTR(err);
if (unlikely(err))
goto out_unpin;
}
h_path.mnt = au_sbr_mnt(sb, bcpup);
au_dtime_store(dt, au_pinned_parent(pin), &h_path);
wh_dentry = NULL;
if (!need_wh)
goto out; /* success, no need to create whiteout */
wh_dentry = au_wh_create(dentry, bcpup, h_path.dentry);
if (IS_ERR(wh_dentry))
goto out_unpin;
/* returns with the parent is locked and wh_dentry is dget-ed */
goto out; /* success */
out_unpin:
au_unpin(pin);
out:
return wh_dentry;
}
/*
* final procedure of adding a new entry, except link(2).
* remove whiteout, instantiate, copyup the parent dir's times and size
* and update version.
* if it failed, re-create the removed whiteout.
*/
static int epilog(struct inode *dir, aufs_bindex_t bindex,
struct dentry *wh_dentry, struct dentry *dentry)
{
int err, rerr;
aufs_bindex_t bwh;
struct path h_path;
struct inode *inode, *h_dir;
struct dentry *wh;
bwh = -1;
if (wh_dentry) {
h_dir = wh_dentry->d_parent->d_inode; /* dir inode is locked */
IMustLock(h_dir);
AuDebugOn(au_h_iptr(dir, bindex) != h_dir);
bwh = au_dbwh(dentry);
h_path.dentry = wh_dentry;
h_path.mnt = au_sbr_mnt(dir->i_sb, bindex);
err = au_wh_unlink_dentry(au_h_iptr(dir, bindex), &h_path,
dentry);
if (unlikely(err))
goto out;
}
inode = au_new_inode(dentry, /*must_new*/1);
if (!IS_ERR(inode)) {
d_instantiate(dentry, inode);
dir = dentry->d_parent->d_inode; /* dir inode is locked */
IMustLock(dir);
if (au_ibstart(dir) == au_dbstart(dentry))
au_cpup_attr_timesizes(dir);
dir->i_version++;
return 0; /* success */
}
err = PTR_ERR(inode);
if (!wh_dentry)
goto out;
/* revert */
/* dir inode is locked */
wh = au_wh_create(dentry, bwh, wh_dentry->d_parent);
rerr = PTR_ERR(wh);
if (IS_ERR(wh)) {
AuIOErr("%.*s reverting whiteout failed(%d, %d)\n",
AuDLNPair(dentry), err, rerr);
err = -EIO;
} else
dput(wh);
out:
return err;
}
/*
* final procedure of adding a new entry, except link(2).
* remove whiteout, instantiate, copyup the parent dir's times and size
* and update version.
* if it failed, re-create the removed whiteout.
*/
static int epilog(struct inode *dir, aufs_bindex_t bindex,
struct dentry *wh_dentry, struct dentry *dentry)
{
int err, rerr;
aufs_bindex_t bwh;
struct inode *inode, *h_dir;
struct dentry *wh;
struct au_ndx ndx;
struct super_block *sb;
LKTRTrace("wh %p, %.*s\n", wh_dentry, AuDLNPair(dentry));
sb = dentry->d_sb;
bwh = -1;
if (wh_dentry) {
h_dir = wh_dentry->d_parent->d_inode; /* dir inode is locked */
IMustLock(h_dir);
AuDebugOn(au_h_iptr(dir, bindex) != h_dir);
bwh = au_dbwh(dentry);
err = au_wh_unlink_dentry(au_hi(dir, bindex), wh_dentry, dentry,
/*dlgt*/0);
if (unlikely(err))
goto out;
}
inode = au_new_inode(dentry, /*must_new*/1);
if (!IS_ERR(inode)) {
d_instantiate(dentry, inode);
dir = dentry->d_parent->d_inode; /* dir inode is locked */
IMustLock(dir);
/* or always cpup dir mtime? */
if (au_ibstart(dir) == au_dbstart(dentry))
au_cpup_attr_timesizes(dir);
dir->i_version++;
return 0; /* success */
}
err = PTR_ERR(inode);
if (!wh_dentry)
goto out;
/* revert */
ndx.flags = 0;
if (au_test_dlgt(au_mntflags(sb)))
au_fset_ndx(ndx.flags, DLGT);
ndx.nfsmnt = au_nfsmnt(sb, bwh);
ndx.nd = NULL;
/* ndx.br = NULL; */
/* dir inode is locked */
wh = au_wh_create(dentry, bwh, wh_dentry->d_parent, &ndx);
rerr = PTR_ERR(wh);
if (IS_ERR(wh)) {
AuIOErr("%.*s reverting whiteout failed(%d, %d)\n",
AuDLNPair(dentry), err, rerr);
err = -EIO;
} else
dput(wh);
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;
}