/*
* The function is nasty, nasty, nasty, but so is rename. :(
*/
static int unionfs_rename_all(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
struct dentry *parent_dentry = NULL;
int err = 0;
int eio;
/* These variables control error handling. */
fd_set success_mask;
char *name = NULL;
/* unfortunately, we have to resort to this, because dbstart/dbend would
return different things in different place of the rename code */
struct rename_info info;
info.rename_ok = FD_SETSIZE; /* The last rename that is ok. */
info.do_copyup = -1; /* Where we should start copyup. */
info.do_whiteout = -1; /* Where we should start whiteouts of the source. */
info.wh_old = NULL;
info.bwh_old = -1;
print_entry_location();
parent_dentry = old_dentry->d_parent;
name = KMALLOC(old_dentry->d_name.len + 1, GFP_KERNEL);
if (!name) {
err = -ENOMEM;
goto out;
}
strncpy(name, old_dentry->d_name.name, old_dentry->d_name.len + 1);
info.new_bstart = dbstart(new_dentry);
info.new_bend = dbend(new_dentry);
info.old_bstart = dbstart(old_dentry);
info.old_bend = dbend(old_dentry);
BUG_ON(info.new_bstart < 0);
BUG_ON(info.old_bstart < 0);
/* The failure mask only can deal with FD_SETSIZE entries. */
BUG_ON(info.old_bend > FD_SETSIZE);
BUG_ON(info.new_bend > FD_SETSIZE);
FD_ZERO(&success_mask);
/* Life is simpler if the dentry doesn't exist. */
info.clobber =
(dtohd_index(new_dentry, info.new_bstart)->d_inode) ? 1 : 0;
info.isdir = S_ISDIR(old_dentry->d_inode->i_mode);
/* rename everything we can */
err =
__rename_all(old_dir, old_dentry, new_dir, new_dentry,
&success_mask, &info);
if (err)
goto revert;
/* unlink destinations even further left */
err =
__rename_all_unlink(old_dir, old_dentry, new_dir, new_dentry,
&info);
if (err)
goto revert;
if (info.clobber) {
/* Now we need to handle the leftmost of the destination. */
err =
__rename_all_clobber(old_dir, old_dentry, new_dir,
new_dentry, &info);
if (err)
goto revert;
}
/* Copy up if necessary */
if (info.do_copyup != -1) {
int bindex;
for (bindex = info.do_copyup; bindex >= 0; bindex--) {
err =
copyup_dentry(old_dentry->d_parent->d_inode,
old_dentry, info.old_bstart, bindex,
NULL, old_dentry->d_inode->i_size);
if (!err) {
DPUT(info.wh_old);
info.bwh_old = bindex;
err =
do_rename(old_dir, old_dentry, new_dir,
new_dentry, bindex, &info.wh_old);
break;
}
}
}
/* Create a whiteout for the source. */
if (info.do_whiteout != -1) {
struct dentry *hidden_parent;
BUG_ON(info.do_whiteout < 0
|| !info.wh_old || IS_ERR(info.wh_old)
|| info.wh_old->d_inode || info.bwh_old < 0);
hidden_parent = lock_parent(info.wh_old);
err = vfs_create(hidden_parent->d_inode, info.wh_old, S_IRUGO,
NULL);
unlock_dir(hidden_parent);
if (!err)
set_dbopaque(old_dentry, info.bwh_old);
else {
/* We can't fix anything now, so we -EIO. */
printk(KERN_WARNING "We can't create a whiteout for the"
"source in rename!\n");
err = -EIO;
goto out;
}
}
/* We are at the point where reverting doesn't happen. */
goto out;
revert:
/* something bad happened, try to revert */
eio =
__rename_all_revert(old_dir, old_dentry, new_dir, new_dentry,
&success_mask, &info);
if (eio)
err = eio;
out:
DPUT(info.wh_old);
KFREE(name);
print_exit_status(err);
return err;
}
struct dentry *unionfs_lookup_backend(struct dentry *dentry, struct nameidata *nd,
int lookupmode)
{
int err = 0;
struct dentry *hidden_dentry = NULL;
struct dentry *wh_hidden_dentry = NULL;
struct dentry *hidden_dir_dentry = NULL;
struct dentry *parent_dentry = NULL;
int bindex, bstart, bend, bopaque;
int dentry_count = 0; /* Number of positive dentries. */
int first_dentry_offset = -1;
struct dentry *first_hidden_dentry = NULL;
struct vfsmount *first_hidden_mnt = NULL;
int locked_parent = 0;
int locked_child = 0;
int opaque;
char *whname = NULL;
const char *name;
int namelen;
/* We should already have a lock on this dentry in the case of a
* partial lookup, or a revalidation. Otherwise it is returned from
* new_dentry_private_data already locked.
*/
if (lookupmode == INTERPOSE_PARTIAL || lookupmode == INTERPOSE_REVAL ||
lookupmode == INTERPOSE_REVAL_NEG)
verify_locked(dentry);
else {
BUG_ON(UNIONFS_D(dentry) != NULL);
locked_child = 1;
}
if (lookupmode != INTERPOSE_PARTIAL)
if ((err = new_dentry_private_data(dentry)))
goto out;
/* must initialize dentry operations */
dentry->d_op = &unionfs_dops;
parent_dentry = dget_parent(dentry);
/* We never partial lookup the root directory. */
if (parent_dentry != dentry) {
unionfs_lock_dentry(parent_dentry);
locked_parent = 1;
} else {
dput(parent_dentry);
parent_dentry = NULL;
goto out;
}
name = dentry->d_name.name;
namelen = dentry->d_name.len;
/* No dentries should get created for possible whiteout names. */
if (!is_validname(name)) {
err = -EPERM;
goto out_free;
}
/* Now start the actual lookup procedure. */
bstart = dbstart(parent_dentry);
bend = dbend(parent_dentry);
bopaque = dbopaque(parent_dentry);
BUG_ON(bstart < 0);
/* It would be ideal if we could convert partial lookups to only have
* to do this work when they really need to. It could probably improve
* performance quite a bit, and maybe simplify the rest of the code.
*/
if (lookupmode == INTERPOSE_PARTIAL) {
bstart++;
if ((bopaque != -1) && (bopaque < bend))
bend = bopaque;
}
for (bindex = bstart; bindex <= bend; bindex++) {
hidden_dentry = unionfs_lower_dentry_idx(dentry, bindex);
if (lookupmode == INTERPOSE_PARTIAL && hidden_dentry)
continue;
BUG_ON(hidden_dentry != NULL);
hidden_dir_dentry = unionfs_lower_dentry_idx(parent_dentry, bindex);
/* if the parent hidden dentry does not exist skip this */
if (!(hidden_dir_dentry && hidden_dir_dentry->d_inode))
continue;
/* also skip it if the parent isn't a directory. */
if (!S_ISDIR(hidden_dir_dentry->d_inode->i_mode))
continue;
/* Reuse the whiteout name because its value doesn't change. */
if (!whname) {
whname = alloc_whname(name, namelen);
if (IS_ERR(whname)) {
err = PTR_ERR(whname);
goto out_free;
}
}
/* check if whiteout exists in this branch: lookup .wh.foo */
wh_hidden_dentry = lookup_one_len(whname, hidden_dir_dentry,
namelen + UNIONFS_WHLEN);
if (IS_ERR(wh_hidden_dentry)) {
dput(first_hidden_dentry);
mntput(first_hidden_mnt);
err = PTR_ERR(wh_hidden_dentry);
goto out_free;
}
if (wh_hidden_dentry->d_inode) {
/* We found a whiteout so lets give up. */
if (S_ISREG(wh_hidden_dentry->d_inode->i_mode)) {
set_dbend(dentry, bindex);
set_dbopaque(dentry, bindex);
dput(wh_hidden_dentry);
break;
}
err = -EIO;
printk(KERN_NOTICE "EIO: Invalid whiteout entry type"
" %d.\n", wh_hidden_dentry->d_inode->i_mode);
dput(wh_hidden_dentry);
dput(first_hidden_dentry);
mntput(first_hidden_mnt);
goto out_free;
}
dput(wh_hidden_dentry);
wh_hidden_dentry = NULL;
/* Now do regular lookup; lookup foo */
nd->dentry = unionfs_lower_dentry_idx(dentry, bindex);
/* FIXME: fix following line for mount point crossing */
nd->mnt = unionfs_lower_mnt_idx(parent_dentry, bindex);
hidden_dentry = lookup_one_len_nd(name, hidden_dir_dentry,
namelen, nd);
if (IS_ERR(hidden_dentry)) {
dput(first_hidden_dentry);
mntput(first_hidden_mnt);
err = PTR_ERR(hidden_dentry);
goto out_free;
}
/* Store the first negative dentry specially, because if they
* are all negative we need this for future creates.
*/
if (!hidden_dentry->d_inode) {
if (!first_hidden_dentry && (dbstart(dentry) == -1)) {
first_hidden_dentry = hidden_dentry;
/* FIXME: following line needs to be changed
* to allow mountpoint crossing
*/
first_hidden_mnt = mntget(
unionfs_lower_mnt_idx(parent_dentry,
bindex));
first_dentry_offset = bindex;
} else
dput(hidden_dentry);
continue;
}
/* number of positive dentries */
dentry_count++;
/* store underlying dentry */
if (dbstart(dentry) == -1)
set_dbstart(dentry, bindex);
unionfs_set_lower_dentry_idx(dentry, bindex, hidden_dentry);
/* FIXME: the following line needs to get fixed to allow
* mountpoint crossing
*/
unionfs_set_lower_mnt_idx(dentry, bindex,
mntget(unionfs_lower_mnt_idx(parent_dentry, bindex)));
set_dbend(dentry, bindex);
/* update parent directory's atime with the bindex */
fsstack_copy_attr_atime(parent_dentry->d_inode,
hidden_dir_dentry->d_inode);
/* We terminate file lookups here. */
if (!S_ISDIR(hidden_dentry->d_inode->i_mode)) {
if (lookupmode == INTERPOSE_PARTIAL)
continue;
if (dentry_count == 1)
goto out_positive;
/* This can only happen with mixed D-*-F-* */
BUG_ON(!S_ISDIR(unionfs_lower_dentry(dentry)->d_inode->i_mode));
continue;
}
opaque = is_opaque_dir(dentry, bindex);
if (opaque < 0) {
dput(first_hidden_dentry);
mntput(first_hidden_mnt);
err = opaque;
goto out_free;
} else if (opaque) {
set_dbend(dentry, bindex);
set_dbopaque(dentry, bindex);
break;
}
}
if (dentry_count)
goto out_positive;
else
goto out_negative;
out_negative:
if (lookupmode == INTERPOSE_PARTIAL)
goto out;
/* If we've only got negative dentries, then use the leftmost one. */
if (lookupmode == INTERPOSE_REVAL) {
if (dentry->d_inode)
UNIONFS_I(dentry->d_inode)->stale = 1;
goto out;
}
/* This should only happen if we found a whiteout. */
if (first_dentry_offset == -1) {
nd->dentry = dentry;
/* FIXME: fix following line for mount point crossing */
nd->mnt = unionfs_lower_mnt_idx(parent_dentry, bindex);
first_hidden_dentry = lookup_one_len_nd(name, hidden_dir_dentry,
namelen, nd);
first_dentry_offset = bindex;
if (IS_ERR(first_hidden_dentry)) {
err = PTR_ERR(first_hidden_dentry);
goto out;
}
/* FIXME: the following line needs to be changed to allow
* mountpoint crossing
*/
first_hidden_mnt = mntget(unionfs_lower_mnt_idx(dentry, bindex));
}
unionfs_set_lower_dentry_idx(dentry, first_dentry_offset, first_hidden_dentry);
unionfs_set_lower_mnt_idx(dentry, first_dentry_offset, first_hidden_mnt);
set_dbstart(dentry, first_dentry_offset);
set_dbend(dentry, first_dentry_offset);
if (lookupmode == INTERPOSE_REVAL_NEG)
BUG_ON(dentry->d_inode != NULL);
else
d_add(dentry, NULL);
goto out;
/* This part of the code is for positive dentries. */
out_positive:
BUG_ON(dentry_count <= 0);
/* If we're holding onto the first negative dentry & corresponding
* vfsmount - throw it out.
*/
dput(first_hidden_dentry);
mntput(first_hidden_mnt);
/* Partial lookups need to reinterpose, or throw away older negs. */
if (lookupmode == INTERPOSE_PARTIAL) {
if (dentry->d_inode) {
unionfs_reinterpose(dentry);
goto out;
}
/* This somehow turned positive, so it is as if we had a
* negative revalidation.
*/
lookupmode = INTERPOSE_REVAL_NEG;
update_bstart(dentry);
bstart = dbstart(dentry);
bend = dbend(dentry);
}
err = unionfs_interpose(dentry, dentry->d_sb, lookupmode);
if (err)
goto out_drop;
goto out;
out_drop:
d_drop(dentry);
out_free:
/* should dput all the underlying dentries on error condition */
bstart = dbstart(dentry);
if (bstart >= 0) {
bend = dbend(dentry);
for (bindex = bstart; bindex <= bend; bindex++) {
dput(unionfs_lower_dentry_idx(dentry, bindex));
mntput(unionfs_lower_mnt_idx(dentry, bindex));
}
}
kfree(UNIONFS_D(dentry)->lower_paths);
UNIONFS_D(dentry)->lower_paths = NULL;
set_dbstart(dentry, -1);
set_dbend(dentry, -1);
out:
if (!err && UNIONFS_D(dentry)) {
BUG_ON(dbend(dentry) > UNIONFS_D(dentry)->bcount);
BUG_ON(dbend(dentry) > sbmax(dentry->d_sb));
BUG_ON(dbstart(dentry) < 0);
}
kfree(whname);
if (locked_parent)
unionfs_unlock_dentry(parent_dentry);
dput(parent_dentry);
if (locked_child)
unionfs_unlock_dentry(dentry);
return ERR_PTR(err);
}
static int unionfs_rename_whiteout(struct inode *old_dir,
struct dentry *old_dentry,
struct inode *new_dir,
struct dentry *new_dentry)
{
int err = 0;
int bindex, bwh_old;
int old_bstart, old_bend;
int new_bstart, new_bend;
int do_copyup = -1;
struct dentry *parent_dentry;
int local_err = 0;
int eio = 0;
int revert = 0;
struct dentry *wh_old = NULL;
print_entry_location();
old_bstart = dbstart(old_dentry);
bwh_old = old_bstart;
old_bend = dbend(old_dentry);
parent_dentry = old_dentry->d_parent;
new_bstart = dbstart(new_dentry);
new_bend = dbend(new_dentry);
/* Rename source to destination. */
err = do_rename(old_dir, old_dentry, new_dir, new_dentry, old_bstart,
&wh_old);
if (err) {
if (!IS_COPYUP_ERR(err)) {
goto out;
}
do_copyup = old_bstart - 1;
} else {
revert = 1;
}
/* Unlink all instances of destination that exist to the left of
* bstart of source. On error, revert back, goto out.
*/
for (bindex = old_bstart - 1; bindex >= new_bstart; bindex--) {
struct dentry *unlink_dentry;
struct dentry *unlink_dir_dentry;
unlink_dentry = dtohd_index(new_dentry, bindex);
if (!unlink_dentry) {
continue;
}
unlink_dir_dentry = lock_parent(unlink_dentry);
if (!(err = is_robranch_super(old_dir->i_sb, bindex))) {
err =
vfs_unlink(unlink_dir_dentry->d_inode,
unlink_dentry);
}
fist_copy_attr_times(new_dentry->d_parent->d_inode,
unlink_dir_dentry->d_inode);
/* propagate number of hard-links */
new_dentry->d_parent->d_inode->i_nlink =
get_nlinks(new_dentry->d_parent->d_inode);
unlock_dir(unlink_dir_dentry);
if (!err) {
if (bindex != new_bstart) {
DPUT(unlink_dentry);
set_dtohd_index(new_dentry, bindex, NULL);
}
} else if (IS_COPYUP_ERR(err)) {
do_copyup = bindex - 1;
} else if (revert) {
DPUT(wh_old);
goto revert;
}
}
if (do_copyup != -1) {
for (bindex = do_copyup; bindex >= 0; bindex--) {
/* copyup the file into some left directory, so that you can rename it */
err =
copyup_dentry(old_dentry->d_parent->d_inode,
old_dentry, old_bstart, bindex, NULL,
old_dentry->d_inode->i_size);
if (!err) {
DPUT(wh_old);
bwh_old = bindex;
err =
do_rename(old_dir, old_dentry, new_dir,
new_dentry, bindex, &wh_old);
break;
}
}
}
/* Create whiteout for source, only if:
* (1) There is more than one underlying instance of source.
* (2) We did a copy_up
*/
if ((old_bstart != old_bend) || (do_copyup != -1)) {
struct dentry *hidden_parent;
BUG_ON(!wh_old || IS_ERR(wh_old) || wh_old->d_inode
|| bwh_old < 0);
hidden_parent = lock_parent(wh_old);
local_err = vfs_create(hidden_parent->d_inode, wh_old, S_IRUGO,
NULL);
unlock_dir(hidden_parent);
if (!local_err)
set_dbopaque(old_dentry, bwh_old);
else {
/* We can't fix anything now, so we cop-out and use -EIO. */
printk
("<0>We can't create a whiteout for the source in rename!\n");
err = -EIO;
}
}
out:
DPUT(wh_old);
print_exit_status(err);
return err;
revert:
/* Do revert here. */
local_err = unionfs_refresh_hidden_dentry(new_dentry, old_bstart);
if (local_err) {
printk(KERN_WARNING
"Revert failed in rename: the new refresh failed.\n");
eio = -EIO;
}
local_err = unionfs_refresh_hidden_dentry(old_dentry, old_bstart);
if (local_err) {
printk(KERN_WARNING
"Revert failed in rename: the old refresh failed.\n");
eio = -EIO;
goto revert_out;
}
if (!dtohd_index(new_dentry, bindex)
|| !dtohd_index(new_dentry, bindex)->d_inode) {
printk(KERN_WARNING
"Revert failed in rename: the object disappeared from under us!\n");
eio = -EIO;
goto revert_out;
}
if (dtohd_index(old_dentry, bindex)
&& dtohd_index(old_dentry, bindex)->d_inode) {
printk(KERN_WARNING
"Revert failed in rename: the object was created underneath us!\n");
eio = -EIO;
goto revert_out;
}
local_err =
do_rename(new_dir, new_dentry, old_dir, old_dentry, old_bstart,
NULL);
/* If we can't fix it, then we cop-out with -EIO. */
if (local_err) {
printk(KERN_WARNING "Revert failed in rename!\n");
eio = -EIO;
}
local_err = unionfs_refresh_hidden_dentry(new_dentry, bindex);
if (local_err)
eio = -EIO;
local_err = unionfs_refresh_hidden_dentry(old_dentry, bindex);
if (local_err)
eio = -EIO;
revert_out:
if (eio)
err = eio;
print_exit_status(err);
return err;
}
struct dentry *unionfs_lookup_backend(struct dentry *dentry, int lookupmode)
{
int err = 0;
struct dentry *hidden_dentry = NULL;
struct dentry *wh_hidden_dentry = NULL;
struct dentry *hidden_dir_dentry = NULL;
struct dentry *parent_dentry = NULL;
int bindex, bstart, bend, bopaque;
int dentry_count = 0; /* Number of positive dentries. */
int first_dentry_offset = -1;
struct dentry *first_hidden_dentry = NULL;
int locked_parent = 0;
int locked_child = 0;
int opaque;
char *whname = NULL;
const char *name;
int namelen;
print_entry("mode = %d", lookupmode);
/* We should already have a lock on this dentry in the case of a
* partial lookup, or a revalidation. Otherwise it is returned from
* new_dentry_private_data already locked. */
if (lookupmode == INTERPOSE_PARTIAL || lookupmode == INTERPOSE_REVAL
|| lookupmode == INTERPOSE_REVAL_NEG) {
verify_locked(dentry);
} else {
BUG_ON(dtopd_nocheck(dentry) != NULL);
locked_child = 1;
}
if (lookupmode != INTERPOSE_PARTIAL)
if ((err = new_dentry_private_data(dentry)))
goto out;
/* must initialize dentry operations */
dentry->d_op = &unionfs_dops;
parent_dentry = GET_PARENT(dentry);
/* We never partial lookup the root directory. */
if (parent_dentry != dentry) {
lock_dentry(parent_dentry);
locked_parent = 1;
} else {
DPUT(parent_dentry);
parent_dentry = NULL;
goto out;
}
fist_print_dentry("IN unionfs_lookup (parent)", parent_dentry);
fist_print_dentry("IN unionfs_lookup (child)", dentry);
name = dentry->d_name.name;
namelen = dentry->d_name.len;
/* No dentries should get created for possible whiteout names. */
if (!is_validname(name)) {
err = -EPERM;
goto out_free;
}
/* Now start the actual lookup procedure. */
bstart = dbstart(parent_dentry);
bend = dbend(parent_dentry);
bopaque = dbopaque(parent_dentry);
BUG_ON(bstart < 0);
/* It would be ideal if we could convert partial lookups to only have
* to do this work when they really need to. It could probably improve
* performance quite a bit, and maybe simplify the rest of the code. */
if (lookupmode == INTERPOSE_PARTIAL) {
bstart++;
if ((bopaque != -1) && (bopaque < bend))
bend = bopaque;
}
fist_dprint(8, "bstart = %d, bend = %d\n", bstart, bend);
for (bindex = bstart; bindex <= bend; bindex++) {
hidden_dentry = dtohd_index(dentry, bindex);
if (lookupmode == INTERPOSE_PARTIAL && hidden_dentry)
continue;
BUG_ON(hidden_dentry != NULL);
hidden_dir_dentry = dtohd_index(parent_dentry, bindex);
/* if the parent hidden dentry does not exist skip this */
if (!(hidden_dir_dentry && hidden_dir_dentry->d_inode))
continue;
/* also skip it if the parent isn't a directory. */
if (!S_ISDIR(hidden_dir_dentry->d_inode->i_mode))
continue;
/* Reuse the whiteout name because its value doesn't change. */
if (!whname) {
whname = alloc_whname(name, namelen);
if (IS_ERR(whname)) {
err = PTR_ERR(whname);
goto out_free;
}
}
/* check if whiteout exists in this branch: lookup .wh.foo */
wh_hidden_dentry = LOOKUP_ONE_LEN(whname, hidden_dir_dentry,
namelen + WHLEN);
if (IS_ERR(wh_hidden_dentry)) {
DPUT(first_hidden_dentry);
err = PTR_ERR(wh_hidden_dentry);
goto out_free;
}
if (wh_hidden_dentry->d_inode) {
/* We found a whiteout so lets give up. */
fist_dprint(8, "whiteout found in %d\n", bindex);
if (S_ISREG(wh_hidden_dentry->d_inode->i_mode)) {
set_dbend(dentry, bindex);
set_dbopaque(dentry, bindex);
DPUT(wh_hidden_dentry);
break;
}
err = -EIO;
printk(KERN_NOTICE "EIO: Invalid whiteout entry type"
" %d.\n", wh_hidden_dentry->d_inode->i_mode);
DPUT(wh_hidden_dentry);
DPUT(first_hidden_dentry);
goto out_free;
}
DPUT(wh_hidden_dentry);
wh_hidden_dentry = NULL;
/* Now do regular lookup; lookup foo */
hidden_dentry = LOOKUP_ONE_LEN(name, hidden_dir_dentry,
namelen);
fist_print_generic_dentry("hidden result", hidden_dentry);
if (IS_ERR(hidden_dentry)) {
DPUT(first_hidden_dentry);
err = PTR_ERR(hidden_dentry);
goto out_free;
}
/* Store the first negative dentry specially, because if they
* are all negative we need this for future creates. */
if (!hidden_dentry->d_inode) {
if (!first_hidden_dentry && (dbstart(dentry) == -1)) {
first_hidden_dentry = hidden_dentry;
first_dentry_offset = bindex;
} else {
DPUT(hidden_dentry);
}
continue;
}
/* number of positive dentries */
dentry_count++;
/* store underlying dentry */
if (dbstart(dentry) == -1)
set_dbstart(dentry, bindex);
set_dtohd_index(dentry, bindex, hidden_dentry);
set_dbend(dentry, bindex);
/* update parent directory's atime with the bindex */
fist_copy_attr_atime(parent_dentry->d_inode,
hidden_dir_dentry->d_inode);
/* We terminate file lookups here. */
if (!S_ISDIR(hidden_dentry->d_inode->i_mode)) {
if (lookupmode == INTERPOSE_PARTIAL)
continue;
if (dentry_count == 1)
goto out_positive;
/* This can only happen with mixed D-*-F-* */
BUG_ON(!S_ISDIR(dtohd(dentry)->d_inode->i_mode));
continue;
}
opaque = is_opaque_dir(dentry, bindex);
if (opaque < 0) {
DPUT(first_hidden_dentry);
err = opaque;
goto out_free;
}
if (opaque) {
set_dbend(dentry, bindex);
set_dbopaque(dentry, bindex);
break;
}
}
if (dentry_count)
goto out_positive;
else
goto out_negative;
out_negative:
if (lookupmode == INTERPOSE_PARTIAL)
goto out;
/* If we've only got negative dentries, then use the leftmost one. */
if (lookupmode == INTERPOSE_REVAL) {
if (dentry->d_inode) {
itopd(dentry->d_inode)->uii_stale = 1;
}
goto out;
}
/* This should only happen if we found a whiteout. */
if (first_dentry_offset == -1) {
first_hidden_dentry = LOOKUP_ONE_LEN(name, hidden_dir_dentry,
namelen);
first_dentry_offset = bindex;
if (IS_ERR(first_hidden_dentry)) {
err = PTR_ERR(first_hidden_dentry);
goto out;
}
}
set_dtohd_index(dentry, first_dentry_offset, first_hidden_dentry);
set_dbstart(dentry, first_dentry_offset);
set_dbend(dentry, first_dentry_offset);
if (lookupmode == INTERPOSE_REVAL_NEG)
BUG_ON(dentry->d_inode != NULL);
else
d_add(dentry, NULL);
goto out;
/* This part of the code is for positive dentries. */
out_positive:
BUG_ON(dentry_count <= 0);
/* If we're holding onto the first negative dentry throw it out. */
DPUT(first_hidden_dentry);
/* Partial lookups need to reinterpose, or throw away older negs. */
if (lookupmode == INTERPOSE_PARTIAL) {
if (dentry->d_inode) {
unionfs_reinterpose(dentry);
goto out;
}
/* This somehow turned positive, so it is as if we had a
* negative revalidation. */
lookupmode = INTERPOSE_REVAL_NEG;
update_bstart(dentry);
bstart = dbstart(dentry);
bend = dbend(dentry);
}
err = unionfs_interpose(dentry, dentry->d_sb, lookupmode);
if (err)
goto out_drop;
fist_checkinode(dentry->d_inode, "unionfs_lookup OUT: child");
fist_checkinode(parent_dentry->d_inode, "unionfs_lookup OUT: dir");
goto out;
out_drop:
d_drop(dentry);
out_free:
/* should dput all the underlying dentries on error condition */
bstart = dbstart(dentry);
if (bstart >= 0) {
bend = dbend(dentry);
for (bindex = bstart; bindex <= bend; bindex++)
DPUT(dtohd_index(dentry, bindex));
}
KFREE(dtohd_ptr(dentry));
dtohd_ptr(dentry) = NULL;
set_dbstart(dentry, -1);
set_dbend(dentry, -1);
out:
if (!err && dtopd(dentry)) {
BUG_ON(dbend(dentry) > dtopd(dentry)->udi_bcount);
BUG_ON(dbend(dentry) > sbmax(dentry->d_sb));
BUG_ON(dbstart(dentry) < 0);
}
KFREE(whname);
fist_print_dentry("OUT unionfs_lookup (parent)", parent_dentry);
fist_print_dentry("OUT unionfs_lookup (child)", dentry);
if (locked_parent)
unlock_dentry(parent_dentry);
DPUT(parent_dentry);
if (locked_child)
unlock_dentry(dentry);
print_exit_status(err);
return ERR_PTR(err);
}
