/*
* 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;
}
/*
* 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;
valid = 0;
if (unlikely(!au_di(dentry)))
goto out;
valid = 1;
sb = dentry->d_sb;
inode = dentry->d_inode;
/*
* todo: very ugly
* i_mutex of parent dir may be held,
* but we should not return 'invalid' due to busy.
*/
err = aufs_read_lock(dentry, AuLock_FLUSH | AuLock_DW | AuLock_NOPLM);
if (unlikely(err)) {
valid = err;
AuTraceErr(err);
goto out;
}
if (unlikely(au_dbrange_test(dentry))) {
err = -EINVAL;
AuTraceErr(err);
goto out_dgrade;
}
sigen = au_sigen(sb);
if (au_digen_test(dentry, sigen)) {
AuDebugOn(IS_ROOT(dentry));
err = au_reval_dpath(dentry, sigen);
if (unlikely(err)) {
AuTraceErr(err);
goto out_dgrade;
}
}
di_downgrade_lock(dentry, AuLock_IR);
err = -EINVAL;
if (inode && (IS_DEADDIR(inode) || !inode->i_nlink))
goto out_inval;
do_udba = !au_opt_test(au_mntflags(sb), UDBA_NONE);
if (do_udba && inode) {
aufs_bindex_t bstart = au_ibstart(inode);
struct inode *h_inode;
if (bstart >= 0) {
h_inode = au_h_iptr(inode, bstart);
if (h_inode && au_test_higen(inode, h_inode))
goto out_inval;
}
}
err = h_d_revalidate(dentry, inode, nd, do_udba);
if (unlikely(!err && do_udba && au_dbstart(dentry) < 0)) {
err = -EIO;
AuDbg("both of real entry and whiteout found, %.*s, err %d\n",
AuDLNPair(dentry), err);
}
goto out_inval;
out_dgrade:
di_downgrade_lock(dentry, AuLock_IR);
out_inval:
aufs_read_unlock(dentry, AuLock_IR);
AuTraceErr(err);
valid = !err;
out:
if (!valid) {
AuDbg("%.*s invalid, %d\n", AuDLNPair(dentry), valid);
d_drop(dentry);
}
return valid;
}
/*
* if valid returns 1, otherwise 0.
*/
static int aufs_d_revalidate(struct dentry *dentry, unsigned int flags)
{
int valid, err;
unsigned int sigen;
unsigned char do_udba;
struct super_block *sb;
struct inode *inode;
/* todo: support rcu-walk? */
if (flags & LOOKUP_RCU)
return -ECHILD;
valid = 0;
if (unlikely(!au_di(dentry)))
goto out;
valid = 1;
sb = dentry->d_sb;
/*
* todo: very ugly
* i_mutex of parent dir may be held,
* but we should not return 'invalid' due to busy.
*/
err = aufs_read_lock(dentry, AuLock_FLUSH | AuLock_DW | AuLock_NOPLM);
if (unlikely(err)) {
valid = err;
AuTraceErr(err);
goto out;
}
inode = NULL;
if (d_really_is_positive(dentry))
inode = d_inode(dentry);
if (unlikely(inode && is_bad_inode(inode))) {
err = -EINVAL;
AuTraceErr(err);
goto out_dgrade;
}
if (unlikely(au_dbrange_test(dentry))) {
err = -EINVAL;
AuTraceErr(err);
goto out_dgrade;
}
sigen = au_sigen(sb);
if (au_digen_test(dentry, sigen)) {
AuDebugOn(IS_ROOT(dentry));
err = au_reval_dpath(dentry, sigen);
if (unlikely(err)) {
AuTraceErr(err);
goto out_dgrade;
}
}
di_downgrade_lock(dentry, AuLock_IR);
err = -EINVAL;
if (!(flags & (LOOKUP_OPEN | LOOKUP_EMPTY))
&& inode
&& !(inode->i_state && I_LINKABLE)
&& (IS_DEADDIR(inode) || !inode->i_nlink))
goto out_inval;
do_udba = !au_opt_test(au_mntflags(sb), UDBA_NONE);
if (do_udba && inode) {
aufs_bindex_t bstart = au_ibstart(inode);
struct inode *h_inode;
if (bstart >= 0) {
h_inode = au_h_iptr(inode, bstart);
if (h_inode && au_test_higen(inode, h_inode))
goto out_inval;
}
}
err = h_d_revalidate(dentry, inode, flags, do_udba);
if (unlikely(!err && do_udba && au_dbstart(dentry) < 0)) {
err = -EIO;
AuDbg("both of real entry and whiteout found, %p, err %d\n",
dentry, err);
}
goto out_inval;
out_dgrade:
di_downgrade_lock(dentry, AuLock_IR);
out_inval:
aufs_read_unlock(dentry, AuLock_IR);
AuTraceErr(err);
valid = !err;
out:
if (!valid) {
AuDbg("%pd invalid, %d\n", dentry, valid);
d_drop(dentry);
}
return valid;
}
