static int simple_reval_dpath(struct dentry *dentry, unsigned int sigen)
{
int err;
struct dentry *parent;
struct inode *inode;
inode = dentry->d_inode;
if (au_digen(dentry) == sigen && au_iigen(inode) == sigen)
return 0;
parent = dget_parent(dentry);
di_read_lock_parent(parent, AuLock_IR);
AuDebugOn(au_digen(parent) != sigen
|| au_iigen(parent->d_inode) != sigen);
au_dbg_verify_gen(parent, sigen);
/* returns a number of positive dentries */
err = au_refresh_hdentry(dentry, inode->i_mode & S_IFMT);
if (err >= 0)
err = au_refresh_hinode(inode, dentry);
di_read_unlock(parent, AuLock_IR);
dput(parent);
return err;
}
/*
* if valid returns 1, otherwise 0.
*/
static int aufs_d_revalidate(struct dentry *dentry, struct nameidata *nd)
{
int valid, err;
unsigned int sigen;
unsigned char do_udba;
struct super_block *sb;
struct inode *inode;
err = -EINVAL;
sb = dentry->d_sb;
inode = dentry->d_inode;
aufs_read_lock(dentry, AuLock_FLUSH | AuLock_DW);
sigen = au_sigen(sb);
if (au_digen(dentry) != sigen) {
AuDebugOn(IS_ROOT(dentry));
if (inode)
err = au_reval_dpath(dentry, sigen);
if (unlikely(err))
goto out_dgrade;
AuDebugOn(au_digen(dentry) != sigen);
}
if (inode && au_iigen(inode) != sigen) {
AuDebugOn(IS_ROOT(dentry));
err = au_refresh_hinode(inode, dentry);
if (unlikely(err))
goto out_dgrade;
AuDebugOn(au_iigen(inode) != sigen);
}
di_downgrade_lock(dentry, AuLock_IR);
AuDebugOn(au_digen(dentry) != sigen);
AuDebugOn(inode && au_iigen(inode) != sigen);
err = -EINVAL;
do_udba = !au_opt_test(au_mntflags(sb), UDBA_NONE);
if (do_udba && inode) {
aufs_bindex_t bstart = au_ibstart(inode);
if (bstart >= 0
&& au_test_higen(inode, au_h_iptr(inode, bstart)))
goto out;
}
err = h_d_revalidate(dentry, inode, nd, do_udba);
if (unlikely(!err && do_udba && au_dbstart(dentry) < 0))
/* both of real entry and whiteout found */
err = -EIO;
goto out;
out_dgrade:
di_downgrade_lock(dentry, AuLock_IR);
out:
aufs_read_unlock(dentry, AuLock_IR);
AuTraceErr(err);
valid = !err;
if (!valid)
AuDbg("%.*s invalid\n", AuDLNPair(dentry));
return valid;
}
int au_reval_dpath(struct dentry *dentry, unsigned int sigen)
{
int err;
struct dentry *d, *parent;
struct inode *inode;
if (!au_ftest_si(au_sbi(dentry->d_sb), FAILED_REFRESH_DIRS))
return simple_reval_dpath(dentry, sigen);
/* slow loop, keep it simple and stupid */
/* cf: au_cpup_dirs() */
err = 0;
parent = NULL;
while (au_digen(dentry) != sigen
|| au_iigen(dentry->d_inode) != sigen) {
d = dentry;
while (1) {
dput(parent);
parent = dget_parent(d);
if (au_digen(parent) == sigen
&& au_iigen(parent->d_inode) == sigen)
break;
d = parent;
}
inode = d->d_inode;
if (d != dentry)
di_write_lock_child(d);
/* someone might update our dentry while we were sleeping */
if (au_digen(d) != sigen || au_iigen(d->d_inode) != sigen) {
di_read_lock_parent(parent, AuLock_IR);
/* returns a number of positive dentries */
err = au_refresh_hdentry(d, inode->i_mode & S_IFMT);
if (err >= 0)
err = au_refresh_hinode(inode, d);
di_read_unlock(parent, AuLock_IR);
}
if (d != dentry)
di_write_unlock(d);
dput(parent);
if (unlikely(err))
break;
}
return err;
}
/*
* successful returns with iinfo write_locked
* minus: errno
* zero: success, matched
* plus: no error, but unmatched
*/
static int reval_inode(struct inode *inode, struct dentry *dentry)
{
int err;
unsigned int gen;
struct au_iigen iigen;
aufs_bindex_t bindex, bend;
struct inode *h_inode, *h_dinode;
/*
* before this function, if aufs got any iinfo lock, it must be only
* one, the parent dir.
* it can happen by UDBA and the obsoleted inode number.
*/
err = -EIO;
if (unlikely(inode->i_ino == parent_ino(dentry)))
goto out;
err = 1;
ii_write_lock_new_child(inode);
h_dinode = au_h_dptr(dentry, au_dbstart(dentry))->d_inode;
bend = au_ibend(inode);
for (bindex = au_ibstart(inode); bindex <= bend; bindex++) {
h_inode = au_h_iptr(inode, bindex);
if (!h_inode || h_inode != h_dinode)
continue;
err = 0;
gen = au_iigen(inode, &iigen);
if (gen == au_digen(dentry)
&& !au_ig_ftest(iigen.ig_flags, HALF_REFRESHED))
break;
/* fully refresh inode using dentry */
err = au_refresh_hinode(inode, dentry);
if (!err)
au_update_iigen(inode, /*half*/0);
break;
}
if (unlikely(err))
ii_write_unlock(inode);
out:
return err;
}
/*
* ->setattr() and ->getattr() are called in various cases.
* chmod, stat: dentry is revalidated.
* fchmod, fstat: file and dentry are not revalidated, additionally they may be
* unhashed.
* for ->setattr(), ia->ia_file is passed from ftruncate only.
*/
static int au_reval_for_attr(struct dentry *dentry, unsigned int sigen)
{
int err;
struct inode *inode;
struct dentry *parent;
err = 0;
inode = dentry->d_inode;
if (au_digen(dentry) != sigen || au_iigen(inode) != sigen) {
parent = dget_parent(dentry);
di_read_lock_parent(parent, AuLock_IR);
/* returns a number of positive dentries */
err = au_refresh_hdentry(dentry, inode->i_mode & S_IFMT);
if (err >= 0)
err = au_refresh_hinode(inode, dentry);
di_read_unlock(parent, AuLock_IR);
dput(parent);
}
AuTraceErr(err);
return err;
}
/* successful returns with iinfo write_locked */
static int reval_inode(struct inode *inode, struct dentry *dentry, int *matched)
{
int err;
aufs_bindex_t bindex, bend;
struct inode *h_inode, *h_dinode;
*matched = 0;
/*
* before this function, if aufs got any iinfo lock, it must be only
* one, the parent dir.
* it can happen by UDBA and the obsoleted inode number.
*/
err = -EIO;
if (unlikely(inode->i_ino == parent_ino(dentry)))
goto out;
err = 0;
ii_write_lock_new_child(inode);
h_dinode = au_h_dptr(dentry, au_dbstart(dentry))->d_inode;
bend = au_ibend(inode);
for (bindex = au_ibstart(inode); bindex <= bend; bindex++) {
h_inode = au_h_iptr(inode, bindex);
if (h_inode && h_inode == h_dinode) {
*matched = 1;
err = 0;
if (au_iigen(inode) != au_digen(dentry))
err = au_refresh_hinode(inode, dentry);
break;
}
}
if (unlikely(err))
ii_write_unlock(inode);
out:
return err;
}
/*
* By adding a dirty branch, a cached dentry may be affected in various ways.
*
* a dirty branch is added
* - on the top of layers
* - in the middle of layers
* - to the bottom of layers
*
* on the added branch there exists
* - a whiteout
* - a diropq
* - a same named entry
* + exist
* * negative --> positive
* * positive --> positive
* - type is unchanged
* - type is changed
* + doesn't exist
* * negative --> negative
* * positive --> negative (rejected by au_br_del() for non-dir case)
* - none
*/
static int au_refresh_by_dinfo(struct dentry *dentry, struct au_dinfo *dinfo,
struct au_dinfo *tmp)
{
int err;
aufs_bindex_t bindex, bend;
struct {
struct dentry *dentry;
struct inode *inode;
mode_t mode;
} orig_h, tmp_h;
struct au_hdentry *hd;
struct inode *inode, *h_inode;
struct dentry *h_dentry;
err = 0;
AuDebugOn(dinfo->di_bstart < 0);
orig_h.dentry = dinfo->di_hdentry[dinfo->di_bstart].hd_dentry;
orig_h.inode = orig_h.dentry->d_inode;
orig_h.mode = 0;
if (orig_h.inode)
orig_h.mode = orig_h.inode->i_mode & S_IFMT;
memset(&tmp_h, 0, sizeof(tmp_h));
if (tmp->di_bstart >= 0) {
tmp_h.dentry = tmp->di_hdentry[tmp->di_bstart].hd_dentry;
tmp_h.inode = tmp_h.dentry->d_inode;
if (tmp_h.inode)
tmp_h.mode = tmp_h.inode->i_mode & S_IFMT;
}
inode = dentry->d_inode;
if (!orig_h.inode) {
AuDbg("nagative originally\n");
if (inode) {
au_hide(dentry);
goto out;
}
AuDebugOn(inode);
AuDebugOn(dinfo->di_bstart != dinfo->di_bend);
AuDebugOn(dinfo->di_bdiropq != -1);
if (!tmp_h.inode) {
AuDbg("negative --> negative\n");
/* should have only one negative lower */
if (tmp->di_bstart >= 0
&& tmp->di_bstart < dinfo->di_bstart) {
AuDebugOn(tmp->di_bstart != tmp->di_bend);
AuDebugOn(dinfo->di_bstart != dinfo->di_bend);
au_set_h_dptr(dentry, dinfo->di_bstart, NULL);
au_di_cp(dinfo, tmp);
hd = tmp->di_hdentry + tmp->di_bstart;
au_set_h_dptr(dentry, tmp->di_bstart,
dget(hd->hd_dentry));
}
au_dbg_verify_dinode(dentry);
} else {
AuDbg("negative --> positive\n");
/*
* similar to the behaviour of creating with bypassing
* aufs.
* unhash it in order to force an error in the
* succeeding create operation.
* we should not set S_DEAD here.
*/
d_drop(dentry);
/* au_di_swap(tmp, dinfo); */
au_dbg_verify_dinode(dentry);
}
} else {
AuDbg("positive originally\n");
/* inode may be NULL */
AuDebugOn(inode && (inode->i_mode & S_IFMT) != orig_h.mode);
if (!tmp_h.inode) {
AuDbg("positive --> negative\n");
/* or bypassing aufs */
au_hide(dentry);
if (tmp->di_bwh >= 0 && tmp->di_bwh <= dinfo->di_bstart)
dinfo->di_bwh = tmp->di_bwh;
if (inode)
err = au_refresh_hinode_self(inode);
au_dbg_verify_dinode(dentry);
} else if (orig_h.mode == tmp_h.mode) {
AuDbg("positive --> positive, same type\n");
if (!S_ISDIR(orig_h.mode)
&& dinfo->di_bstart > tmp->di_bstart) {
/*
* similar to the behaviour of removing and
* creating.
*/
au_hide(dentry);
if (inode)
err = au_refresh_hinode_self(inode);
au_dbg_verify_dinode(dentry);
} else {
/* fill empty slots */
if (dinfo->di_bstart > tmp->di_bstart)
dinfo->di_bstart = tmp->di_bstart;
if (dinfo->di_bend < tmp->di_bend)
dinfo->di_bend = tmp->di_bend;
dinfo->di_bwh = tmp->di_bwh;
dinfo->di_bdiropq = tmp->di_bdiropq;
hd = tmp->di_hdentry;
bend = dinfo->di_bend;
for (bindex = tmp->di_bstart; bindex <= bend;
bindex++) {
if (au_h_dptr(dentry, bindex))
continue;
h_dentry = hd[bindex].hd_dentry;
if (!h_dentry)
continue;
h_inode = h_dentry->d_inode;
AuDebugOn(!h_inode);
AuDebugOn(orig_h.mode
!= (h_inode->i_mode
& S_IFMT));
au_set_h_dptr(dentry, bindex,
dget(h_dentry));
}
err = au_refresh_hinode(inode, dentry);
au_dbg_verify_dinode(dentry);
}
} else {
AuDbg("positive --> positive, different type\n");
/* similar to the behaviour of removing and creating */
au_hide(dentry);
if (inode)
err = au_refresh_hinode_self(inode);
au_dbg_verify_dinode(dentry);
}
}
out:
return err;
}
