/*
* initialize or clean the whiteouts for an adding branch
*/
static int au_br_init_wh(struct super_block *sb, struct au_branch *br,
int new_perm, struct dentry *h_root)
{
int err, old_perm;
aufs_bindex_t bindex;
struct mutex *h_mtx;
struct au_wbr *wbr;
struct au_hinode *hdir;
wbr = br->br_wbr;
old_perm = br->br_perm;
br->br_perm = new_perm;
hdir = NULL;
h_mtx = NULL;
bindex = au_br_index(sb, br->br_id);
if (0 <= bindex) {
hdir = au_hi(sb->s_root->d_inode, bindex);
au_hn_imtx_lock_nested(hdir, AuLsc_I_PARENT);
} else {
h_mtx = &h_root->d_inode->i_mutex;
mutex_lock_nested(h_mtx, AuLsc_I_PARENT);
}
if (!wbr)
err = au_wh_init(h_root, br, sb);
else {
wbr_wh_write_lock(wbr);
err = au_wh_init(h_root, br, sb);
wbr_wh_write_unlock(wbr);
}
if (hdir)
au_hn_imtx_unlock(hdir);
else
mutex_unlock(h_mtx);
br->br_perm = old_perm;
if (!err && wbr && !au_br_writable(new_perm)) {
kfree(wbr);
br->br_wbr = NULL;
}
return err;
}
int au_opts_verify(struct super_block *sb, unsigned long sb_flags,
unsigned int pending)
{
int err;
aufs_bindex_t bindex, bend;
unsigned char do_plink, skip, do_free;
struct au_branch *br;
struct au_wbr *wbr;
struct dentry *root;
struct inode *dir, *h_dir;
struct au_sbinfo *sbinfo;
struct au_hinode *hdir;
SiMustAnyLock(sb);
sbinfo = au_sbi(sb);
AuDebugOn(!(sbinfo->si_mntflags & AuOptMask_UDBA));
if (!(sb_flags & MS_RDONLY)) {
if (unlikely(!au_br_writable(au_sbr_perm(sb, 0))))
pr_warn("first branch should be rw\n");
if (unlikely(au_opt_test(sbinfo->si_mntflags, SHWH)))
pr_warn("shwh should be used with ro\n");
}
if (au_opt_test((sbinfo->si_mntflags | pending), UDBA_HNOTIFY)
&& !au_opt_test(sbinfo->si_mntflags, XINO))
pr_warn("udba=*notify requires xino\n");
err = 0;
root = sb->s_root;
dir = root->d_inode;
do_plink = !!au_opt_test(sbinfo->si_mntflags, PLINK);
bend = au_sbend(sb);
for (bindex = 0; !err && bindex <= bend; bindex++) {
skip = 0;
h_dir = au_h_iptr(dir, bindex);
br = au_sbr(sb, bindex);
do_free = 0;
wbr = br->br_wbr;
if (wbr)
wbr_wh_read_lock(wbr);
if (!au_br_writable(br->br_perm)) {
do_free = !!wbr;
skip = (!wbr
|| (!wbr->wbr_whbase
&& !wbr->wbr_plink
&& !wbr->wbr_orph));
} else if (!au_br_wh_linkable(br->br_perm)) {
/* skip = (!br->br_whbase && !br->br_orph); */
skip = (!wbr || !wbr->wbr_whbase);
if (skip && wbr) {
if (do_plink)
skip = !!wbr->wbr_plink;
else
skip = !wbr->wbr_plink;
}
} else {
/* skip = (br->br_whbase && br->br_ohph); */
skip = (wbr && wbr->wbr_whbase);
if (skip) {
if (do_plink)
skip = !!wbr->wbr_plink;
else
skip = !wbr->wbr_plink;
}
}
if (wbr)
wbr_wh_read_unlock(wbr);
if (skip)
continue;
hdir = au_hi(dir, bindex);
au_hn_imtx_lock_nested(hdir, AuLsc_I_PARENT);
if (wbr)
wbr_wh_write_lock(wbr);
err = au_wh_init(br, sb);
if (wbr)
wbr_wh_write_unlock(wbr);
au_hn_imtx_unlock(hdir);
if (!err && do_free) {
kfree(wbr);
br->br_wbr = NULL;
}
}
return err;
}
int au_opts_verify(struct super_block *sb, unsigned long sb_flags,
unsigned int pending)
{
int err, fhsm;
aufs_bindex_t bindex, bend;
unsigned char do_plink, skip, do_free;
struct au_branch *br;
struct au_wbr *wbr;
struct dentry *root;
struct inode *dir, *h_dir;
struct au_sbinfo *sbinfo;
struct au_hinode *hdir;
SiMustAnyLock(sb);
sbinfo = au_sbi(sb);
AuDebugOn(!(sbinfo->si_mntflags & AuOptMask_UDBA));
if (!(sb_flags & MS_RDONLY)) {
if (unlikely(!au_br_writable(au_sbr_perm(sb, 0))))
pr_warn("first branch should be rw\n");
if (unlikely(au_opt_test(sbinfo->si_mntflags, SHWH)))
pr_warn("shwh should be used with ro\n");
}
if (au_opt_test((sbinfo->si_mntflags | pending), UDBA_HNOTIFY)
&& !au_opt_test(sbinfo->si_mntflags, XINO))
pr_warn("udba=*notify requires xino\n");
if (au_opt_test(sbinfo->si_mntflags, DIRPERM1))
pr_warn("dirperm1 breaks the protection"
" by the permission bits on the lower branch\n");
err = 0;
fhsm = 0;
root = sb->s_root;
dir = root->d_inode;
do_plink = !!au_opt_test(sbinfo->si_mntflags, PLINK);
bend = au_sbend(sb);
for (bindex = 0; !err && bindex <= bend; bindex++) {
skip = 0;
h_dir = au_h_iptr(dir, bindex);
br = au_sbr(sb, bindex);
if ((br->br_perm & AuBrAttr_ICEX)
&& !h_dir->i_op->listxattr)
br->br_perm &= ~AuBrAttr_ICEX;
#if 0
if ((br->br_perm & AuBrAttr_ICEX_SEC)
&& (au_br_sb(br)->s_flags & MS_NOSEC))
br->br_perm &= ~AuBrAttr_ICEX_SEC;
#endif
do_free = 0;
wbr = br->br_wbr;
if (wbr)
wbr_wh_read_lock(wbr);
if (!au_br_writable(br->br_perm)) {
do_free = !!wbr;
skip = (!wbr
|| (!wbr->wbr_whbase
&& !wbr->wbr_plink
&& !wbr->wbr_orph));
} else if (!au_br_wh_linkable(br->br_perm)) {
/* skip = (!br->br_whbase && !br->br_orph); */
skip = (!wbr || !wbr->wbr_whbase);
if (skip && wbr) {
if (do_plink)
skip = !!wbr->wbr_plink;
else
skip = !wbr->wbr_plink;
}
} else {
/* skip = (br->br_whbase && br->br_ohph); */
skip = (wbr && wbr->wbr_whbase);
if (skip) {
if (do_plink)
skip = !!wbr->wbr_plink;
else
skip = !wbr->wbr_plink;
}
}
if (wbr)
wbr_wh_read_unlock(wbr);
if (au_br_fhsm(br->br_perm)) {
fhsm++;
AuDebugOn(!br->br_fhsm);
}
if (skip)
continue;
hdir = au_hi(dir, bindex);
au_hn_imtx_lock_nested(hdir, AuLsc_I_PARENT);
if (wbr)
wbr_wh_write_lock(wbr);
err = au_wh_init(br, sb);
if (wbr)
wbr_wh_write_unlock(wbr);
au_hn_imtx_unlock(hdir);
if (!err && do_free) {
kfree(wbr);
br->br_wbr = NULL;
}
}
if (fhsm >= 2) {
au_fset_si(sbinfo, FHSM);
for (bindex = bend; bindex >= 0; bindex--) {
br = au_sbr(sb, bindex);
if (au_br_fhsm(br->br_perm)) {
au_fhsm_set_bottom(sb, bindex);
break;
}
}
} else {
au_fclr_si(sbinfo, FHSM);
au_fhsm_set_bottom(sb, -1);
}
return err;
}