static void au_ren_rev_whsrc(int err, struct au_ren_args *a)
{
int rerr;
a->h_path.dentry = a->src_wh_dentry;
rerr = au_wh_unlink_dentry(a->src_h_dir, &a->h_path, a->src_dentry);
au_set_dbwh(a->src_dentry, a->src_bwh);
if (rerr)
RevertFailure("unlink %.*s", AuDLNPair(a->src_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;
}
static int au_cpdown_dir_wh(struct dentry *dentry, struct dentry *h_parent,
struct inode *dir, aufs_bindex_t bdst)
{
int err;
struct path h_path;
struct au_branch *br;
br = au_sbr(dentry->d_sb, bdst);
h_path.dentry = au_wh_lkup(h_parent, &dentry->d_name, br);
err = PTR_ERR(h_path.dentry);
if (IS_ERR(h_path.dentry))
goto out;
err = 0;
if (h_path.dentry->d_inode) {
h_path.mnt = br->br_mnt;
err = au_wh_unlink_dentry(au_h_iptr(dir, bdst), &h_path,
dentry);
}
dput(h_path.dentry);
out:
return err;
}
/*
* when an error happened, remove the created whiteout and revert everything.
*/
static int do_revert(int err, struct inode *dir, aufs_bindex_t bindex,
aufs_bindex_t bwh, struct dentry *wh_dentry,
struct dentry *dentry, struct au_dtime *dt)
{
int rerr;
struct path h_path = {
.dentry = wh_dentry,
.mnt = au_sbr_mnt(dir->i_sb, bindex)
};
rerr = au_wh_unlink_dentry(au_h_iptr(dir, bindex), &h_path, dentry);
if (!rerr) {
au_set_dbwh(dentry, bwh);
au_dtime_revert(dt);
return 0;
}
AuIOErr("%.*s reverting whiteout failed(%d, %d)\n",
AuDLNPair(dentry), err, rerr);
return -EIO;
}
/* ---------------------------------------------------------------------- */
int aufs_unlink(struct inode *dir, struct dentry *dentry)
{
int err;
aufs_bindex_t bwh, bindex, bstart;
struct au_dtime dt;
struct au_pin pin;
struct path h_path;
struct inode *inode, *h_dir;
struct dentry *parent, *wh_dentry;
IMustLock(dir);
err = aufs_read_lock(dentry, AuLock_DW | AuLock_GEN);
if (unlikely(err))
goto out;
err = au_d_hashed_positive(dentry);
if (unlikely(err))
goto out_unlock;
inode = dentry->d_inode;
IMustLock(inode);
err = -EISDIR;
if (unlikely(S_ISDIR(inode->i_mode)))
goto out_unlock; /* possible? */
bstart = au_dbstart(dentry);
bwh = au_dbwh(dentry);
bindex = -1;
parent = dentry->d_parent; /* dir inode is locked */
di_write_lock_parent(parent);
wh_dentry = lock_hdir_create_wh(dentry, /*isdir*/0, &bindex, &dt, &pin);
err = PTR_ERR(wh_dentry);
if (IS_ERR(wh_dentry))
goto out_parent;
h_path.mnt = au_sbr_mnt(dentry->d_sb, bstart);
h_path.dentry = au_h_dptr(dentry, bstart);
dget(h_path.dentry);
if (bindex == bstart) {
h_dir = au_pinned_h_dir(&pin);
err = vfsub_unlink(h_dir, &h_path, /*force*/0);
} else {
/* dir inode is locked */
h_dir = wh_dentry->d_parent->d_inode;
IMustLock(h_dir);
err = 0;
}
if (!err) {
vfsub_drop_nlink(inode);
epilog(dir, dentry, bindex);
/* update target timestamps */
if (bindex == bstart) {
vfsub_update_h_iattr(&h_path, /*did*/NULL); /*ignore*/
inode->i_ctime = h_path.dentry->d_inode->i_ctime;
} else
/* todo: this timestamp may be reverted later */
inode->i_ctime = h_dir->i_ctime;
goto out_unpin; /* success */
}
/* revert */
if (wh_dentry) {
int rerr;
rerr = do_revert(err, dir, bindex, bwh, wh_dentry, dentry, &dt);
if (rerr)
err = rerr;
}
out_unpin:
au_unpin(&pin);
dput(wh_dentry);
dput(h_path.dentry);
out_parent:
di_write_unlock(parent);
out_unlock:
aufs_read_unlock(dentry, AuLock_DW);
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;
}
int aufs_link(struct dentry *src_dentry, struct inode *dir,
struct dentry *dentry)
{
int err, rerr;
struct au_dtime dt;
struct au_link_args *a;
struct dentry *wh_dentry, *h_src_dentry;
struct inode *inode;
struct super_block *sb;
struct au_wr_dir_args wr_dir_args = {
/* .force_btgt = -1, */
.flags = AuWrDir_ADD_ENTRY
};
IMustLock(dir);
inode = src_dentry->d_inode;
IMustLock(inode);
err = -ENOMEM;
a = kzalloc(sizeof(*a), GFP_NOFS);
if (unlikely(!a))
goto out;
a->parent = dentry->d_parent; /* dir inode is locked */
err = aufs_read_and_write_lock2(dentry, src_dentry,
AuLock_NOPLM | AuLock_GEN);
if (unlikely(err))
goto out_kfree;
err = au_d_hashed_positive(src_dentry);
if (unlikely(err))
goto out_unlock;
err = au_d_may_add(dentry);
if (unlikely(err))
goto out_unlock;
a->src_parent = dget_parent(src_dentry);
wr_dir_args.force_btgt = au_ibstart(inode);
di_write_lock_parent(a->parent);
wr_dir_args.force_btgt = au_wbr(dentry, wr_dir_args.force_btgt);
wh_dentry = lock_hdir_lkup_wh(dentry, &dt, src_dentry, &a->pin,
&wr_dir_args);
err = PTR_ERR(wh_dentry);
if (IS_ERR(wh_dentry))
goto out_parent;
err = 0;
sb = dentry->d_sb;
a->bdst = au_dbstart(dentry);
a->h_path.dentry = au_h_dptr(dentry, a->bdst);
a->h_path.mnt = au_sbr_mnt(sb, a->bdst);
a->bsrc = au_ibstart(inode);
h_src_dentry = au_h_d_alias(src_dentry, a->bsrc);
if (!h_src_dentry) {
a->bsrc = au_dbstart(src_dentry);
h_src_dentry = au_h_d_alias(src_dentry, a->bsrc);
AuDebugOn(!h_src_dentry);
} else if (IS_ERR(h_src_dentry))
goto out_parent;
if (au_opt_test(au_mntflags(sb), PLINK)) {
if (a->bdst < a->bsrc
/* && h_src_dentry->d_sb != a->h_path.dentry->d_sb */)
err = au_cpup_or_link(src_dentry, a);
else
err = vfsub_link(h_src_dentry, au_pinned_h_dir(&a->pin),
&a->h_path);
dput(h_src_dentry);
} else {
/*
* copyup src_dentry to the branch we process,
* and then link(2) to it.
*/
dput(h_src_dentry);
if (a->bdst < a->bsrc
/* && h_src_dentry->d_sb != a->h_path.dentry->d_sb */) {
au_unpin(&a->pin);
di_write_unlock(a->parent);
err = au_cpup_before_link(src_dentry, a);
di_write_lock_parent(a->parent);
if (!err)
err = au_pin(&a->pin, dentry, a->bdst,
au_opt_udba(sb),
AuPin_DI_LOCKED | AuPin_MNT_WRITE);
if (unlikely(err))
goto out_wh;
}
if (!err) {
h_src_dentry = au_h_dptr(src_dentry, a->bdst);
err = -ENOENT;
if (h_src_dentry && h_src_dentry->d_inode)
err = vfsub_link(h_src_dentry,
au_pinned_h_dir(&a->pin),
&a->h_path);
}
}
if (unlikely(err))
goto out_unpin;
if (wh_dentry) {
a->h_path.dentry = wh_dentry;
err = au_wh_unlink_dentry(au_pinned_h_dir(&a->pin), &a->h_path,
dentry);
if (unlikely(err))
goto out_revert;
}
dir->i_version++;
if (au_ibstart(dir) == au_dbstart(dentry))
au_cpup_attr_timesizes(dir);
inc_nlink(inode);
inode->i_ctime = dir->i_ctime;
d_instantiate(dentry, au_igrab(inode));
if (d_unhashed(a->h_path.dentry))
/* some filesystem calls d_drop() */
d_drop(dentry);
goto out_unpin; /* success */
out_revert:
rerr = vfsub_unlink(au_pinned_h_dir(&a->pin), &a->h_path, /*force*/0);
if (unlikely(rerr)) {
AuIOErr("%.*s reverting failed(%d, %d)\n",
AuDLNPair(dentry), err, rerr);
err = -EIO;
}
au_dtime_revert(&dt);
out_unpin:
au_unpin(&a->pin);
out_wh:
dput(wh_dentry);
out_parent:
di_write_unlock(a->parent);
dput(a->src_parent);
out_unlock:
if (unlikely(err)) {
au_update_dbstart(dentry);
d_drop(dentry);
}
aufs_read_and_write_unlock2(dentry, src_dentry);
out_kfree:
kfree(a);
out:
return err;
}
/*
* when an error happened, remove the created whiteout and revert everything.
*/
static int do_revert(int err, struct inode *dir, aufs_bindex_t bindex,
aufs_bindex_t bwh, struct dentry *wh_dentry,
struct dentry *dentry, struct au_dtime *dt)
{
int rerr;
struct path h_path = {
.dentry = wh_dentry,
.mnt = au_sbr_mnt(dir->i_sb, bindex)
};
rerr = au_wh_unlink_dentry(au_h_iptr(dir, bindex), &h_path, dentry);
if (!rerr) {
au_set_dbwh(dentry, bwh);
au_dtime_revert(dt);
return 0;
}
AuIOErr("%pd reverting whiteout failed(%d, %d)\n", dentry, err, rerr);
return -EIO;
}
/* ---------------------------------------------------------------------- */
int aufs_unlink(struct inode *dir, struct dentry *dentry)
{
int err;
aufs_bindex_t bwh, bindex, bstart;
struct inode *inode, *h_dir, *delegated;
struct dentry *parent, *wh_dentry;
/* to reuduce stack size */
struct {
struct au_dtime dt;
struct au_pin pin;
struct path h_path;
} *a;
IMustLock(dir);
err = -ENOMEM;
a = kmalloc(sizeof(*a), GFP_NOFS);
if (unlikely(!a))
goto out;
err = aufs_read_lock(dentry, AuLock_DW | AuLock_GEN);
if (unlikely(err))
goto out_free;
err = au_d_hashed_positive(dentry);
if (unlikely(err))
goto out_unlock;
inode = d_inode(dentry);
IMustLock(inode);
err = -EISDIR;
if (unlikely(d_is_dir(dentry)))
goto out_unlock; /* possible? */
bstart = au_dbstart(dentry);
bwh = au_dbwh(dentry);
bindex = -1;
parent = dentry->d_parent; /* dir inode is locked */
di_write_lock_parent(parent);
wh_dentry = lock_hdir_create_wh(dentry, /*isdir*/0, &bindex, &a->dt,
&a->pin);
err = PTR_ERR(wh_dentry);
if (IS_ERR(wh_dentry))
goto out_parent;
a->h_path.mnt = au_sbr_mnt(dentry->d_sb, bstart);
a->h_path.dentry = au_h_dptr(dentry, bstart);
dget(a->h_path.dentry);
if (bindex == bstart) {
h_dir = au_pinned_h_dir(&a->pin);
delegated = NULL;
err = vfsub_unlink(h_dir, &a->h_path, &delegated, /*force*/0);
if (unlikely(err == -EWOULDBLOCK)) {
pr_warn("cannot retry for NFSv4 delegation"
" for an internal unlink\n");
iput(delegated);
}
} else {
/* dir inode is locked */
h_dir = d_inode(wh_dentry->d_parent);
IMustLock(h_dir);
err = 0;
}
if (!err) {
vfsub_drop_nlink(inode);
epilog(dir, dentry, bindex);
/* update target timestamps */
if (bindex == bstart) {
vfsub_update_h_iattr(&a->h_path, /*did*/NULL);
/*ignore*/
inode->i_ctime = d_inode(a->h_path.dentry)->i_ctime;
} else
/* todo: this timestamp may be reverted later */
inode->i_ctime = h_dir->i_ctime;
goto out_unpin; /* success */
}
/* revert */
if (wh_dentry) {
int rerr;
rerr = do_revert(err, dir, bindex, bwh, wh_dentry, dentry,
&a->dt);
if (rerr)
err = rerr;
}
out_unpin:
au_unpin(&a->pin);
dput(wh_dentry);
dput(a->h_path.dentry);
out_parent:
di_write_unlock(parent);
out_unlock:
aufs_read_unlock(dentry, AuLock_DW);
out_free:
kfree(a);
out:
return err;
}