/usr/src/aufs-4.9+20161219/fs/aufs/mvdown.c is in aufs-dkms 4.9+20161219-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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* Copyright (C) 2011-2016 Junjiro R. Okajima
*
* This program, aufs is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* move-down, opposite of copy-up
*/
#include "aufs.h"
struct au_mvd_args {
struct {
struct super_block *h_sb;
struct dentry *h_parent;
struct au_hinode *hdir;
struct inode *h_dir, *h_inode;
struct au_pin pin;
} info[AUFS_MVDOWN_NARRAY];
struct aufs_mvdown mvdown;
struct dentry *dentry, *parent;
struct inode *inode, *dir;
struct super_block *sb;
aufs_bindex_t bopq, bwh, bfound;
unsigned char rename_lock;
};
#define mvd_errno mvdown.au_errno
#define mvd_bsrc mvdown.stbr[AUFS_MVDOWN_UPPER].bindex
#define mvd_src_brid mvdown.stbr[AUFS_MVDOWN_UPPER].brid
#define mvd_bdst mvdown.stbr[AUFS_MVDOWN_LOWER].bindex
#define mvd_dst_brid mvdown.stbr[AUFS_MVDOWN_LOWER].brid
#define mvd_h_src_sb info[AUFS_MVDOWN_UPPER].h_sb
#define mvd_h_src_parent info[AUFS_MVDOWN_UPPER].h_parent
#define mvd_hdir_src info[AUFS_MVDOWN_UPPER].hdir
#define mvd_h_src_dir info[AUFS_MVDOWN_UPPER].h_dir
#define mvd_h_src_inode info[AUFS_MVDOWN_UPPER].h_inode
#define mvd_pin_src info[AUFS_MVDOWN_UPPER].pin
#define mvd_h_dst_sb info[AUFS_MVDOWN_LOWER].h_sb
#define mvd_h_dst_parent info[AUFS_MVDOWN_LOWER].h_parent
#define mvd_hdir_dst info[AUFS_MVDOWN_LOWER].hdir
#define mvd_h_dst_dir info[AUFS_MVDOWN_LOWER].h_dir
#define mvd_h_dst_inode info[AUFS_MVDOWN_LOWER].h_inode
#define mvd_pin_dst info[AUFS_MVDOWN_LOWER].pin
#define AU_MVD_PR(flag, ...) do { \
if (flag) \
pr_err(__VA_ARGS__); \
} while (0)
static int find_lower_writable(struct au_mvd_args *a)
{
struct super_block *sb;
aufs_bindex_t bindex, bbot;
struct au_branch *br;
sb = a->sb;
bindex = a->mvd_bsrc;
bbot = au_sbbot(sb);
if (a->mvdown.flags & AUFS_MVDOWN_FHSM_LOWER)
for (bindex++; bindex <= bbot; bindex++) {
br = au_sbr(sb, bindex);
if (au_br_fhsm(br->br_perm)
&& (!(au_br_sb(br)->s_flags & MS_RDONLY)))
return bindex;
}
else if (!(a->mvdown.flags & AUFS_MVDOWN_ROLOWER))
for (bindex++; bindex <= bbot; bindex++) {
br = au_sbr(sb, bindex);
if (!au_br_rdonly(br))
return bindex;
}
else
for (bindex++; bindex <= bbot; bindex++) {
br = au_sbr(sb, bindex);
if (!(au_br_sb(br)->s_flags & MS_RDONLY)) {
if (au_br_rdonly(br))
a->mvdown.flags
|= AUFS_MVDOWN_ROLOWER_R;
return bindex;
}
}
return -1;
}
/* make the parent dir on bdst */
static int au_do_mkdir(const unsigned char dmsg, struct au_mvd_args *a)
{
int err;
err = 0;
a->mvd_hdir_src = au_hi(a->dir, a->mvd_bsrc);
a->mvd_hdir_dst = au_hi(a->dir, a->mvd_bdst);
a->mvd_h_src_parent = au_h_dptr(a->parent, a->mvd_bsrc);
a->mvd_h_dst_parent = NULL;
if (au_dbbot(a->parent) >= a->mvd_bdst)
a->mvd_h_dst_parent = au_h_dptr(a->parent, a->mvd_bdst);
if (!a->mvd_h_dst_parent) {
err = au_cpdown_dirs(a->dentry, a->mvd_bdst);
if (unlikely(err)) {
AU_MVD_PR(dmsg, "cpdown_dirs failed\n");
goto out;
}
a->mvd_h_dst_parent = au_h_dptr(a->parent, a->mvd_bdst);
}
out:
AuTraceErr(err);
return err;
}
/* lock them all */
static int au_do_lock(const unsigned char dmsg, struct au_mvd_args *a)
{
int err;
struct dentry *h_trap;
a->mvd_h_src_sb = au_sbr_sb(a->sb, a->mvd_bsrc);
a->mvd_h_dst_sb = au_sbr_sb(a->sb, a->mvd_bdst);
err = au_pin(&a->mvd_pin_dst, a->dentry, a->mvd_bdst,
au_opt_udba(a->sb),
AuPin_MNT_WRITE | AuPin_DI_LOCKED);
AuTraceErr(err);
if (unlikely(err)) {
AU_MVD_PR(dmsg, "pin_dst failed\n");
goto out;
}
if (a->mvd_h_src_sb != a->mvd_h_dst_sb) {
a->rename_lock = 0;
au_pin_init(&a->mvd_pin_src, a->dentry, a->mvd_bsrc,
AuLsc_DI_PARENT, AuLsc_I_PARENT3,
au_opt_udba(a->sb),
AuPin_MNT_WRITE | AuPin_DI_LOCKED);
err = au_do_pin(&a->mvd_pin_src);
AuTraceErr(err);
a->mvd_h_src_dir = d_inode(a->mvd_h_src_parent);
if (unlikely(err)) {
AU_MVD_PR(dmsg, "pin_src failed\n");
goto out_dst;
}
goto out; /* success */
}
a->rename_lock = 1;
au_pin_hdir_unlock(&a->mvd_pin_dst);
err = au_pin(&a->mvd_pin_src, a->dentry, a->mvd_bsrc,
au_opt_udba(a->sb),
AuPin_MNT_WRITE | AuPin_DI_LOCKED);
AuTraceErr(err);
a->mvd_h_src_dir = d_inode(a->mvd_h_src_parent);
if (unlikely(err)) {
AU_MVD_PR(dmsg, "pin_src failed\n");
au_pin_hdir_lock(&a->mvd_pin_dst);
goto out_dst;
}
au_pin_hdir_unlock(&a->mvd_pin_src);
h_trap = vfsub_lock_rename(a->mvd_h_src_parent, a->mvd_hdir_src,
a->mvd_h_dst_parent, a->mvd_hdir_dst);
if (h_trap) {
err = (h_trap != a->mvd_h_src_parent);
if (err)
err = (h_trap != a->mvd_h_dst_parent);
}
BUG_ON(err); /* it should never happen */
if (unlikely(a->mvd_h_src_dir != au_pinned_h_dir(&a->mvd_pin_src))) {
err = -EBUSY;
AuTraceErr(err);
vfsub_unlock_rename(a->mvd_h_src_parent, a->mvd_hdir_src,
a->mvd_h_dst_parent, a->mvd_hdir_dst);
au_pin_hdir_lock(&a->mvd_pin_src);
au_unpin(&a->mvd_pin_src);
au_pin_hdir_lock(&a->mvd_pin_dst);
goto out_dst;
}
goto out; /* success */
out_dst:
au_unpin(&a->mvd_pin_dst);
out:
AuTraceErr(err);
return err;
}
static void au_do_unlock(const unsigned char dmsg, struct au_mvd_args *a)
{
if (!a->rename_lock)
au_unpin(&a->mvd_pin_src);
else {
vfsub_unlock_rename(a->mvd_h_src_parent, a->mvd_hdir_src,
a->mvd_h_dst_parent, a->mvd_hdir_dst);
au_pin_hdir_lock(&a->mvd_pin_src);
au_unpin(&a->mvd_pin_src);
au_pin_hdir_lock(&a->mvd_pin_dst);
}
au_unpin(&a->mvd_pin_dst);
}
/* copy-down the file */
static int au_do_cpdown(const unsigned char dmsg, struct au_mvd_args *a)
{
int err;
struct au_cp_generic cpg = {
.dentry = a->dentry,
.bdst = a->mvd_bdst,
.bsrc = a->mvd_bsrc,
.len = -1,
.pin = &a->mvd_pin_dst,
.flags = AuCpup_DTIME | AuCpup_HOPEN
};
AuDbg("b%d, b%d\n", cpg.bsrc, cpg.bdst);
if (a->mvdown.flags & AUFS_MVDOWN_OWLOWER)
au_fset_cpup(cpg.flags, OVERWRITE);
if (a->mvdown.flags & AUFS_MVDOWN_ROLOWER)
au_fset_cpup(cpg.flags, RWDST);
err = au_sio_cpdown_simple(&cpg);
if (unlikely(err))
AU_MVD_PR(dmsg, "cpdown failed\n");
AuTraceErr(err);
return err;
}
/*
* unlink the whiteout on bdst if exist which may be created by UDBA while we
* were sleeping
*/
static int au_do_unlink_wh(const unsigned char dmsg, struct au_mvd_args *a)
{
int err;
struct path h_path;
struct au_branch *br;
struct inode *delegated;
br = au_sbr(a->sb, a->mvd_bdst);
h_path.dentry = au_wh_lkup(a->mvd_h_dst_parent, &a->dentry->d_name, br);
err = PTR_ERR(h_path.dentry);
if (IS_ERR(h_path.dentry)) {
AU_MVD_PR(dmsg, "wh_lkup failed\n");
goto out;
}
err = 0;
if (d_is_positive(h_path.dentry)) {
h_path.mnt = au_br_mnt(br);
delegated = NULL;
err = vfsub_unlink(d_inode(a->mvd_h_dst_parent), &h_path,
&delegated, /*force*/0);
if (unlikely(err == -EWOULDBLOCK)) {
pr_warn("cannot retry for NFSv4 delegation"
" for an internal unlink\n");
iput(delegated);
}
if (unlikely(err))
AU_MVD_PR(dmsg, "wh_unlink failed\n");
}
dput(h_path.dentry);
out:
AuTraceErr(err);
return err;
}
/*
* unlink the topmost h_dentry
*/
static int au_do_unlink(const unsigned char dmsg, struct au_mvd_args *a)
{
int err;
struct path h_path;
struct inode *delegated;
h_path.mnt = au_sbr_mnt(a->sb, a->mvd_bsrc);
h_path.dentry = au_h_dptr(a->dentry, a->mvd_bsrc);
delegated = NULL;
err = vfsub_unlink(a->mvd_h_src_dir, &h_path, &delegated, /*force*/0);
if (unlikely(err == -EWOULDBLOCK)) {
pr_warn("cannot retry for NFSv4 delegation"
" for an internal unlink\n");
iput(delegated);
}
if (unlikely(err))
AU_MVD_PR(dmsg, "unlink failed\n");
AuTraceErr(err);
return err;
}
/* Since mvdown succeeded, we ignore an error of this function */
static void au_do_stfs(const unsigned char dmsg, struct au_mvd_args *a)
{
int err;
struct au_branch *br;
a->mvdown.flags |= AUFS_MVDOWN_STFS_FAILED;
br = au_sbr(a->sb, a->mvd_bsrc);
err = au_br_stfs(br, &a->mvdown.stbr[AUFS_MVDOWN_UPPER].stfs);
if (!err) {
br = au_sbr(a->sb, a->mvd_bdst);
a->mvdown.stbr[AUFS_MVDOWN_LOWER].brid = br->br_id;
err = au_br_stfs(br, &a->mvdown.stbr[AUFS_MVDOWN_LOWER].stfs);
}
if (!err)
a->mvdown.flags &= ~AUFS_MVDOWN_STFS_FAILED;
else
AU_MVD_PR(dmsg, "statfs failed (%d), ignored\n", err);
}
/*
* copy-down the file and unlink the bsrc file.
* - unlink the bdst whout if exist
* - copy-down the file (with whtmp name and rename)
* - unlink the bsrc file
*/
static int au_do_mvdown(const unsigned char dmsg, struct au_mvd_args *a)
{
int err;
err = au_do_mkdir(dmsg, a);
if (!err)
err = au_do_lock(dmsg, a);
if (unlikely(err))
goto out;
/*
* do not revert the activities we made on bdst since they should be
* harmless in aufs.
*/
err = au_do_cpdown(dmsg, a);
if (!err)
err = au_do_unlink_wh(dmsg, a);
if (!err && !(a->mvdown.flags & AUFS_MVDOWN_KUPPER))
err = au_do_unlink(dmsg, a);
if (unlikely(err))
goto out_unlock;
AuDbg("%pd2, 0x%x, %d --> %d\n",
a->dentry, a->mvdown.flags, a->mvd_bsrc, a->mvd_bdst);
if (find_lower_writable(a) < 0)
a->mvdown.flags |= AUFS_MVDOWN_BOTTOM;
if (a->mvdown.flags & AUFS_MVDOWN_STFS)
au_do_stfs(dmsg, a);
/* maintain internal array */
if (!(a->mvdown.flags & AUFS_MVDOWN_KUPPER)) {
au_set_h_dptr(a->dentry, a->mvd_bsrc, NULL);
au_set_dbtop(a->dentry, a->mvd_bdst);
au_set_h_iptr(a->inode, a->mvd_bsrc, NULL, /*flags*/0);
au_set_ibtop(a->inode, a->mvd_bdst);
} else {
/* hide the lower */
au_set_h_dptr(a->dentry, a->mvd_bdst, NULL);
au_set_dbbot(a->dentry, a->mvd_bsrc);
au_set_h_iptr(a->inode, a->mvd_bdst, NULL, /*flags*/0);
au_set_ibbot(a->inode, a->mvd_bsrc);
}
if (au_dbbot(a->dentry) < a->mvd_bdst)
au_set_dbbot(a->dentry, a->mvd_bdst);
if (au_ibbot(a->inode) < a->mvd_bdst)
au_set_ibbot(a->inode, a->mvd_bdst);
out_unlock:
au_do_unlock(dmsg, a);
out:
AuTraceErr(err);
return err;
}
/* ---------------------------------------------------------------------- */
/* make sure the file is idle */
static int au_mvd_args_busy(const unsigned char dmsg, struct au_mvd_args *a)
{
int err, plinked;
err = 0;
plinked = !!au_opt_test(au_mntflags(a->sb), PLINK);
if (au_dbtop(a->dentry) == a->mvd_bsrc
&& au_dcount(a->dentry) == 1
&& atomic_read(&a->inode->i_count) == 1
/* && a->mvd_h_src_inode->i_nlink == 1 */
&& (!plinked || !au_plink_test(a->inode))
&& a->inode->i_nlink == 1)
goto out;
err = -EBUSY;
AU_MVD_PR(dmsg,
"b%d, d{b%d, c%d?}, i{c%d?, l%u}, hi{l%u}, p{%d, %d}\n",
a->mvd_bsrc, au_dbtop(a->dentry), au_dcount(a->dentry),
atomic_read(&a->inode->i_count), a->inode->i_nlink,
a->mvd_h_src_inode->i_nlink,
plinked, plinked ? au_plink_test(a->inode) : 0);
out:
AuTraceErr(err);
return err;
}
/* make sure the parent dir is fine */
static int au_mvd_args_parent(const unsigned char dmsg,
struct au_mvd_args *a)
{
int err;
aufs_bindex_t bindex;
err = 0;
if (unlikely(au_alive_dir(a->parent))) {
err = -ENOENT;
AU_MVD_PR(dmsg, "parent dir is dead\n");
goto out;
}
a->bopq = au_dbdiropq(a->parent);
bindex = au_wbr_nonopq(a->dentry, a->mvd_bdst);
AuDbg("b%d\n", bindex);
if (unlikely((bindex >= 0 && bindex < a->mvd_bdst)
|| (a->bopq != -1 && a->bopq < a->mvd_bdst))) {
err = -EINVAL;
a->mvd_errno = EAU_MVDOWN_OPAQUE;
AU_MVD_PR(dmsg, "ancestor is opaque b%d, b%d\n",
a->bopq, a->mvd_bdst);
}
out:
AuTraceErr(err);
return err;
}
static int au_mvd_args_intermediate(const unsigned char dmsg,
struct au_mvd_args *a)
{
int err;
struct au_dinfo *dinfo, *tmp;
/* lookup the next lower positive entry */
err = -ENOMEM;
tmp = au_di_alloc(a->sb, AuLsc_DI_TMP);
if (unlikely(!tmp))
goto out;
a->bfound = -1;
a->bwh = -1;
dinfo = au_di(a->dentry);
au_di_cp(tmp, dinfo);
au_di_swap(tmp, dinfo);
/* returns the number of positive dentries */
err = au_lkup_dentry(a->dentry, a->mvd_bsrc + 1,
/* AuLkup_IGNORE_PERM */ 0);
if (!err)
a->bwh = au_dbwh(a->dentry);
else if (err > 0)
a->bfound = au_dbtop(a->dentry);
au_di_swap(tmp, dinfo);
au_rw_write_unlock(&tmp->di_rwsem);
au_di_free(tmp);
if (unlikely(err < 0))
AU_MVD_PR(dmsg, "failed look-up lower\n");
/*
* here, we have these cases.
* bfound == -1
* no positive dentry under bsrc. there are more sub-cases.
* bwh < 0
* there no whiteout, we can safely move-down.
* bwh <= bsrc
* impossible
* bsrc < bwh && bwh < bdst
* there is a whiteout on RO branch. cannot proceed.
* bwh == bdst
* there is a whiteout on the RW target branch. it should
* be removed.
* bdst < bwh
* there is a whiteout somewhere unrelated branch.
* -1 < bfound && bfound <= bsrc
* impossible.
* bfound < bdst
* found, but it is on RO branch between bsrc and bdst. cannot
* proceed.
* bfound == bdst
* found, replace it if AUFS_MVDOWN_FORCE is set. otherwise return
* error.
* bdst < bfound
* found, after we create the file on bdst, it will be hidden.
*/
AuDebugOn(a->bfound == -1
&& a->bwh != -1
&& a->bwh <= a->mvd_bsrc);
AuDebugOn(-1 < a->bfound
&& a->bfound <= a->mvd_bsrc);
err = -EINVAL;
if (a->bfound == -1
&& a->mvd_bsrc < a->bwh
&& a->bwh != -1
&& a->bwh < a->mvd_bdst) {
a->mvd_errno = EAU_MVDOWN_WHITEOUT;
AU_MVD_PR(dmsg, "bsrc %d, bdst %d, bfound %d, bwh %d\n",
a->mvd_bsrc, a->mvd_bdst, a->bfound, a->bwh);
goto out;
} else if (a->bfound != -1 && a->bfound < a->mvd_bdst) {
a->mvd_errno = EAU_MVDOWN_UPPER;
AU_MVD_PR(dmsg, "bdst %d, bfound %d\n",
a->mvd_bdst, a->bfound);
goto out;
}
err = 0; /* success */
out:
AuTraceErr(err);
return err;
}
static int au_mvd_args_exist(const unsigned char dmsg, struct au_mvd_args *a)
{
int err;
err = 0;
if (!(a->mvdown.flags & AUFS_MVDOWN_OWLOWER)
&& a->bfound == a->mvd_bdst)
err = -EEXIST;
AuTraceErr(err);
return err;
}
static int au_mvd_args(const unsigned char dmsg, struct au_mvd_args *a)
{
int err;
struct au_branch *br;
err = -EISDIR;
if (unlikely(S_ISDIR(a->inode->i_mode)))
goto out;
err = -EINVAL;
if (!(a->mvdown.flags & AUFS_MVDOWN_BRID_UPPER))
a->mvd_bsrc = au_ibtop(a->inode);
else {
a->mvd_bsrc = au_br_index(a->sb, a->mvd_src_brid);
if (unlikely(a->mvd_bsrc < 0
|| (a->mvd_bsrc < au_dbtop(a->dentry)
|| au_dbbot(a->dentry) < a->mvd_bsrc
|| !au_h_dptr(a->dentry, a->mvd_bsrc))
|| (a->mvd_bsrc < au_ibtop(a->inode)
|| au_ibbot(a->inode) < a->mvd_bsrc
|| !au_h_iptr(a->inode, a->mvd_bsrc)))) {
a->mvd_errno = EAU_MVDOWN_NOUPPER;
AU_MVD_PR(dmsg, "no upper\n");
goto out;
}
}
if (unlikely(a->mvd_bsrc == au_sbbot(a->sb))) {
a->mvd_errno = EAU_MVDOWN_BOTTOM;
AU_MVD_PR(dmsg, "on the bottom\n");
goto out;
}
a->mvd_h_src_inode = au_h_iptr(a->inode, a->mvd_bsrc);
br = au_sbr(a->sb, a->mvd_bsrc);
err = au_br_rdonly(br);
if (!(a->mvdown.flags & AUFS_MVDOWN_ROUPPER)) {
if (unlikely(err))
goto out;
} else if (!(vfsub_native_ro(a->mvd_h_src_inode)
|| IS_APPEND(a->mvd_h_src_inode))) {
if (err)
a->mvdown.flags |= AUFS_MVDOWN_ROUPPER_R;
/* go on */
} else
goto out;
err = -EINVAL;
if (!(a->mvdown.flags & AUFS_MVDOWN_BRID_LOWER)) {
a->mvd_bdst = find_lower_writable(a);
if (unlikely(a->mvd_bdst < 0)) {
a->mvd_errno = EAU_MVDOWN_BOTTOM;
AU_MVD_PR(dmsg, "no writable lower branch\n");
goto out;
}
} else {
a->mvd_bdst = au_br_index(a->sb, a->mvd_dst_brid);
if (unlikely(a->mvd_bdst < 0
|| au_sbbot(a->sb) < a->mvd_bdst)) {
a->mvd_errno = EAU_MVDOWN_NOLOWERBR;
AU_MVD_PR(dmsg, "no lower brid\n");
goto out;
}
}
err = au_mvd_args_busy(dmsg, a);
if (!err)
err = au_mvd_args_parent(dmsg, a);
if (!err)
err = au_mvd_args_intermediate(dmsg, a);
if (!err)
err = au_mvd_args_exist(dmsg, a);
if (!err)
AuDbg("b%d, b%d\n", a->mvd_bsrc, a->mvd_bdst);
out:
AuTraceErr(err);
return err;
}
int au_mvdown(struct dentry *dentry, struct aufs_mvdown __user *uarg)
{
int err, e;
unsigned char dmsg;
struct au_mvd_args *args;
struct inode *inode;
inode = d_inode(dentry);
err = -EPERM;
if (unlikely(!capable(CAP_SYS_ADMIN)))
goto out;
err = -ENOMEM;
args = kmalloc(sizeof(*args), GFP_NOFS);
if (unlikely(!args))
goto out;
err = copy_from_user(&args->mvdown, uarg, sizeof(args->mvdown));
if (!err)
err = !access_ok(VERIFY_WRITE, uarg, sizeof(*uarg));
if (unlikely(err)) {
err = -EFAULT;
AuTraceErr(err);
goto out_free;
}
AuDbg("flags 0x%x\n", args->mvdown.flags);
args->mvdown.flags &= ~(AUFS_MVDOWN_ROLOWER_R | AUFS_MVDOWN_ROUPPER_R);
args->mvdown.au_errno = 0;
args->dentry = dentry;
args->inode = inode;
args->sb = dentry->d_sb;
err = -ENOENT;
dmsg = !!(args->mvdown.flags & AUFS_MVDOWN_DMSG);
args->parent = dget_parent(dentry);
args->dir = d_inode(args->parent);
inode_lock_nested(args->dir, I_MUTEX_PARENT);
dput(args->parent);
if (unlikely(args->parent != dentry->d_parent)) {
AU_MVD_PR(dmsg, "parent dir is moved\n");
goto out_dir;
}
inode_lock_nested(inode, I_MUTEX_CHILD);
err = aufs_read_lock(dentry, AuLock_DW | AuLock_FLUSH | AuLock_NOPLMW);
if (unlikely(err))
goto out_inode;
di_write_lock_parent(args->parent);
err = au_mvd_args(dmsg, args);
if (unlikely(err))
goto out_parent;
err = au_do_mvdown(dmsg, args);
if (unlikely(err))
goto out_parent;
au_cpup_attr_timesizes(args->dir);
au_cpup_attr_timesizes(inode);
if (!(args->mvdown.flags & AUFS_MVDOWN_KUPPER))
au_cpup_igen(inode, au_h_iptr(inode, args->mvd_bdst));
/* au_digen_dec(dentry); */
out_parent:
di_write_unlock(args->parent);
aufs_read_unlock(dentry, AuLock_DW);
out_inode:
inode_unlock(inode);
out_dir:
inode_unlock(args->dir);
out_free:
e = copy_to_user(uarg, &args->mvdown, sizeof(args->mvdown));
if (unlikely(e))
err = -EFAULT;
au_delayed_kfree(args);
out:
AuTraceErr(err);
return err;
}
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