/*
* This function creates a copy of a file represented by 'file' which
* currently resides in branch 'bstart' to branch 'new_bindex.' The copy
* will be named "name".
*/
int copyup_named_file(struct inode *dir, struct file *file, char *name,
int bstart, int new_bindex, loff_t len)
{
int err = 0;
struct file *output_file = NULL;
err = copyup_dentry(dir, file->f_path.dentry, bstart, new_bindex,
name, strlen(name), &output_file, len);
if (!err) {
fbstart(file) = new_bindex;
unionfs_set_lower_file_idx(file, new_bindex, output_file);
}
return err;
}
/*
* This function creates a copy of a file represented by 'file' which
* currently resides in branch 'bstart' to branch 'new_bindex'.
*/
int copyup_file(struct inode *dir, struct file *file, int bstart,
int new_bindex, loff_t len)
{
int err = 0;
struct file *output_file = NULL;
struct dentry *dentry = file->f_path.dentry;
err = copyup_dentry(dir, dentry, bstart, new_bindex,
dentry->d_name.name, dentry->d_name.len,
&output_file, len);
if (!err) {
fbstart(file) = new_bindex;
unionfs_set_lower_file_idx(file, new_bindex, output_file);
}
return err;
}
/* This function creates a copy of a file represented by 'file' which currently
* resides in branch 'bstart' to branch 'new_bindex.
*/
int copyup_file(struct inode *dir, struct file *file, int bstart,
int new_bindex, int len)
{
int err = 0;
struct file *output_file = NULL;
print_entry_location();
err = copyup_dentry(dir, file->f_dentry, bstart, new_bindex,
&output_file, len);
if (!err) {
fbstart(file) = new_bindex;
set_ftohf_index(file, new_bindex, output_file);
}
print_exit_status(err);
return err;
}
static int unionfs_setattr(struct dentry *dentry, struct iattr *ia)
{
int err = 0;
struct dentry *lower_dentry;
struct dentry *parent;
struct inode *inode;
struct inode *lower_inode;
int bstart, bend, bindex;
loff_t size;
struct iattr lower_ia;
/* check if user has permission to change inode */
err = inode_change_ok(dentry->d_inode, ia);
if (err)
goto out_err;
unionfs_read_lock(dentry->d_sb, UNIONFS_SMUTEX_CHILD);
parent = unionfs_lock_parent(dentry, UNIONFS_DMUTEX_PARENT);
unionfs_lock_dentry(dentry, UNIONFS_DMUTEX_CHILD);
if (unlikely(!__unionfs_d_revalidate(dentry, parent, false, 0))) {
err = -ESTALE;
goto out;
}
bstart = dbstart(dentry);
bend = dbend(dentry);
inode = dentry->d_inode;
/*
* mode change is for clearing setuid/setgid. Allow lower filesystem
* to reinterpret it in its own way.
*/
if (ia->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
ia->ia_valid &= ~ATTR_MODE;
lower_dentry = unionfs_lower_dentry(dentry);
if (!lower_dentry) { /* should never happen after above revalidate */
err = -EINVAL;
goto out;
}
/*
* Get the lower inode directly from lower dentry, in case ibstart
* is -1 (which happens when the file is open but unlinked.
*/
lower_inode = lower_dentry->d_inode;
/* check if user has permission to change lower inode */
err = inode_change_ok(lower_inode, ia);
if (err)
goto out;
/* copyup if the file is on a read only branch */
if (is_robranch_super(dentry->d_sb, bstart)
|| __is_rdonly(lower_inode)) {
/* check if we have a branch to copy up to */
if (bstart <= 0) {
err = -EACCES;
goto out;
}
if (ia->ia_valid & ATTR_SIZE)
size = ia->ia_size;
else
size = i_size_read(inode);
/* copyup to next available branch */
for (bindex = bstart - 1; bindex >= 0; bindex--) {
err = copyup_dentry(parent->d_inode,
dentry, bstart, bindex,
dentry->d_name.name,
dentry->d_name.len,
NULL, size);
if (!err)
break;
}
if (err)
goto out;
/* get updated lower_dentry/inode after copyup */
lower_dentry = unionfs_lower_dentry(dentry);
lower_inode = unionfs_lower_inode(inode);
/*
* check for whiteouts in writeable branch, and remove them
* if necessary.
*/
if (lower_dentry) {
err = check_unlink_whiteout(dentry, lower_dentry,
bindex);
if (err > 0) /* ignore if whiteout found and removed */
err = 0;
}
}
/*
* If shrinking, first truncate upper level to cancel writing dirty
* pages beyond the new eof; and also if its' maxbytes is more
* limiting (fail with -EFBIG before making any change to the lower
* level). There is no need to vmtruncate the upper level
* afterwards in the other cases: we fsstack_copy_inode_size from
* the lower level.
*/
if (ia->ia_valid & ATTR_SIZE) {
err = inode_newsize_ok(inode, ia->ia_size);
if (err)
goto out;
truncate_setsize(inode, ia->ia_size);
}
/* notify the (possibly copied-up) lower inode */
/*
* Note: we use lower_dentry->d_inode, because lower_inode may be
* unlinked (no inode->i_sb and i_ino==0. This happens if someone
* tries to open(), unlink(), then ftruncate() a file.
*/
/* prepare our own lower struct iattr (with our own lower file) */
memcpy(&lower_ia, ia, sizeof(lower_ia));
if (ia->ia_valid & ATTR_FILE) {
lower_ia.ia_file = unionfs_lower_file(ia->ia_file);
BUG_ON(!lower_ia.ia_file); // XXX?
}
mutex_lock(&lower_dentry->d_inode->i_mutex);
err = notify_change(lower_dentry, &lower_ia);
mutex_unlock(&lower_dentry->d_inode->i_mutex);
if (err)
goto out;
/* get attributes from the first lower inode */
if (ibstart(inode) >= 0)
unionfs_copy_attr_all(inode, lower_inode);
/*
* unionfs_copy_attr_all will copy the lower times to our inode if
* the lower ones are newer (useful for cache coherency). However,
* ->setattr is the only place in which we may have to copy the
* lower inode times absolutely, to support utimes(2).
*/
if (ia->ia_valid & ATTR_MTIME_SET)
inode->i_mtime = lower_inode->i_mtime;
if (ia->ia_valid & ATTR_CTIME)
inode->i_ctime = lower_inode->i_ctime;
if (ia->ia_valid & ATTR_ATIME_SET)
inode->i_atime = lower_inode->i_atime;
fsstack_copy_inode_size(inode, lower_inode);
out:
if (!err)
unionfs_check_dentry(dentry);
unionfs_unlock_dentry(dentry);
unionfs_unlock_parent(dentry, parent);
unionfs_read_unlock(dentry->d_sb);
out_err:
return err;
}
static int unionfs_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *new_dentry)
{
int err = 0;
struct dentry *lower_old_dentry = NULL;
struct dentry *lower_new_dentry = NULL;
struct dentry *lower_dir_dentry = NULL;
struct dentry *old_parent, *new_parent;
char *name = NULL;
bool valid;
unionfs_read_lock(old_dentry->d_sb, UNIONFS_SMUTEX_CHILD);
old_parent = dget_parent(old_dentry);
new_parent = dget_parent(new_dentry);
unionfs_double_lock_parents(old_parent, new_parent);
unionfs_double_lock_dentry(old_dentry, new_dentry);
valid = __unionfs_d_revalidate(old_dentry, old_parent, false, 0);
if (unlikely(!valid)) {
err = -ESTALE;
goto out;
}
if (new_dentry->d_inode) {
valid = __unionfs_d_revalidate(new_dentry, new_parent, false, 0);
if (unlikely(!valid)) {
err = -ESTALE;
goto out;
}
}
lower_new_dentry = unionfs_lower_dentry(new_dentry);
/* check for a whiteout in new dentry branch, and delete it */
err = check_unlink_whiteout(new_dentry, lower_new_dentry,
dbstart(new_dentry));
if (err > 0) { /* whiteout found and removed successfully */
lower_dir_dentry = dget_parent(lower_new_dentry);
fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
dput(lower_dir_dentry);
set_nlink(dir, unionfs_get_nlinks(dir));
err = 0;
}
if (err)
goto out;
/* check if parent hierachy is needed, then link in same branch */
if (dbstart(old_dentry) != dbstart(new_dentry)) {
lower_new_dentry = create_parents(dir, new_dentry,
new_dentry->d_name.name,
dbstart(old_dentry));
err = PTR_ERR(lower_new_dentry);
if (IS_COPYUP_ERR(err))
goto docopyup;
if (!lower_new_dentry || IS_ERR(lower_new_dentry))
goto out;
}
lower_new_dentry = unionfs_lower_dentry(new_dentry);
lower_old_dentry = unionfs_lower_dentry(old_dentry);
BUG_ON(dbstart(old_dentry) != dbstart(new_dentry));
lower_dir_dentry = lock_parent(lower_new_dentry);
err = is_robranch(old_dentry);
if (!err) {
/* see Documentation/filesystems/unionfs/issues.txt */
lockdep_off();
err = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
lower_new_dentry);
lockdep_on();
}
unlock_dir(lower_dir_dentry);
docopyup:
if (IS_COPYUP_ERR(err)) {
int old_bstart = dbstart(old_dentry);
int bindex;
for (bindex = old_bstart - 1; bindex >= 0; bindex--) {
err = copyup_dentry(old_parent->d_inode,
old_dentry, old_bstart,
bindex, old_dentry->d_name.name,
old_dentry->d_name.len, NULL,
i_size_read(old_dentry->d_inode));
if (err)
continue;
lower_new_dentry =
create_parents(dir, new_dentry,
new_dentry->d_name.name,
bindex);
lower_old_dentry = unionfs_lower_dentry(old_dentry);
lower_dir_dentry = lock_parent(lower_new_dentry);
/* see Documentation/filesystems/unionfs/issues.txt */
lockdep_off();
/* do vfs_link */
err = vfs_link(lower_old_dentry,
lower_dir_dentry->d_inode,
lower_new_dentry);
lockdep_on();
unlock_dir(lower_dir_dentry);
goto check_link;
}
goto out;
}
check_link:
if (err || !lower_new_dentry->d_inode)
goto out;
/* Its a hard link, so use the same inode */
new_dentry->d_inode = igrab(old_dentry->d_inode);
d_add(new_dentry, new_dentry->d_inode);
unionfs_copy_attr_all(dir, lower_new_dentry->d_parent->d_inode);
fsstack_copy_inode_size(dir, lower_new_dentry->d_parent->d_inode);
/* propagate number of hard-links */
set_nlink(old_dentry->d_inode,
unionfs_get_nlinks(old_dentry->d_inode));
/* new dentry's ctime may have changed due to hard-link counts */
unionfs_copy_attr_times(new_dentry->d_inode);
out:
if (!new_dentry->d_inode)
d_drop(new_dentry);
kfree(name);
if (!err)
unionfs_postcopyup_setmnt(new_dentry);
unionfs_check_inode(dir);
unionfs_check_dentry(new_dentry);
unionfs_check_dentry(old_dentry);
unionfs_double_unlock_dentry(old_dentry, new_dentry);
unionfs_double_unlock_parents(old_parent, new_parent);
dput(new_parent);
dput(old_parent);
unionfs_read_unlock(old_dentry->d_sb);
return 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;
}
/*
* 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;
}
static int u2fs_setattr(struct dentry *dentry, struct iattr *ia)
{
int err = 0;
struct dentry *lower_dentry=NULL;
struct inode *inode;
struct inode *lower_inode=NULL;
struct dentry *parent = NULL;
struct path lower_path;
struct iattr lower_ia;
inode = dentry->d_inode;
/*
* Check if user has permission to change inode. We don't check if
* this user can change the lower inode: that should happen when
* calling notify_change on the lower inode.
*/
err = inode_change_ok(inode, ia);
if (err)
goto out_err;
/* creating parent directories if destination is read-only */
if((U2FS_D(dentry)->lower_path[LEFT].dentry) == NULL &&
(U2FS_D(dentry)->lower_path[LEFT].mnt) == NULL){
parent = dget_parent(dentry);
err = copyup_dentry(parent->d_inode, dentry,
dentry->d_name.name, dentry->d_name.len,
NULL, i_size_read(dentry->d_inode));
if(err)
goto out;
}
u2fs_get_lower_path(dentry, &lower_path, LEFT);
lower_dentry = lower_path.dentry;
lower_inode = u2fs_lower_inode(inode, LEFT);
/* prepare our own lower struct iattr (with the lower file) */
memcpy(&lower_ia, ia, sizeof(lower_ia));
if (ia->ia_valid & ATTR_FILE)
lower_ia.ia_file = u2fs_lower_file(ia->ia_file, LEFT);
/*
* If shrinking, first truncate upper level to cancel writing dirty
* pages beyond the new eof; and also if its' maxbytes is more
* limiting (fail with -EFBIG before making any change to the lower
* level). There is no need to vmtruncate the upper level
* afterwards in the other cases: we fsstack_copy_inode_size from
* the lower level.
*/
if (ia->ia_valid & ATTR_SIZE) {
err = inode_newsize_ok(inode, ia->ia_size);
if (err)
goto out;
truncate_setsize(inode, ia->ia_size);
}
/*
* mode change is for clearing setuid/setgid bits. Allow lower fs
* to interpret this in its own way.
*/
if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
lower_ia.ia_valid &= ~ATTR_MODE;
/* notify the (possibly copied-up) lower inode */
/*
* Note: we use lower_dentry->d_inode, because lower_inode may be
* unlinked (no inode->i_sb and i_ino==0. This happens if someone
* tries to open(), unlink(), then ftruncate() a file.
*/
mutex_lock(&lower_dentry->d_inode->i_mutex);
err = notify_change(lower_dentry, &lower_ia); /* note: lower_ia */
mutex_unlock(&lower_dentry->d_inode->i_mutex);
if (err)
goto out;
/* get attributes from the lower inode */
fsstack_copy_attr_all(inode, lower_inode);
/*
* Not running fsstack_copy_inode_size(inode, lower_inode), because
* VFS should update our inode size, and notify_change on
* lower_inode should update its size.
*/
out:
if(parent != NULL)
dput(parent);
u2fs_put_lower_path(dentry, &lower_path);
out_err:
return err;
}
/*
* The locking rules in u2fs_rename are complex. We could use a simpler
* superblock-level name-space lock for renames and copy-ups.
*/
static int u2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
int err = 0;
struct dentry *lower_old_dentry = NULL;
struct dentry *lower_new_dentry = NULL;
struct dentry *lower_old_dir_dentry = NULL;
struct dentry *lower_new_dir_dentry = NULL;
struct dentry *trap = NULL;
struct dentry *ret = NULL;
struct path lower_old_path, lower_new_path;
/* creating parent directories if destination is read-only */
if((U2FS_D(old_dentry)->lower_path[LEFT].dentry) == NULL &&
(U2FS_D(old_dentry)->lower_path[LEFT].mnt) == NULL){
err = create_whiteout(old_dentry);
if(err){
err = -EIO;
goto out_copyup;
}
err = copyup_dentry(old_dir, old_dentry,
old_dentry->d_name.name, old_dentry->d_name.len,
NULL, i_size_read(old_dentry->d_inode));
if(err)
goto out_copyup;
}
if((U2FS_D(new_dentry)->lower_path[LEFT].dentry) == NULL &&
(U2FS_D(new_dentry)->lower_path[LEFT].mnt) == NULL){
ret = create_parents(new_dir, new_dentry,
new_dentry->d_name.name);
if (!ret || IS_ERR(ret)) {
err = PTR_ERR(ret);
if (!IS_COPYUP_ERR(err))
printk(KERN_ERR
"u2fs: create_parents for "
"u2fs_rename failed"
"err=%d\n", err);
goto out_copyup;
}
u2fs_postcopyup_setmnt(new_dentry);
u2fs_put_reset_lower_path(new_dentry, RIGHT);
if(err)
goto out_copyup;
}
u2fs_get_lower_path(old_dentry, &lower_old_path, LEFT);
u2fs_get_lower_path(new_dentry, &lower_new_path, LEFT);
lower_old_dentry = lower_old_path.dentry;
lower_new_dentry = lower_new_path.dentry;
lower_old_dir_dentry = dget_parent(lower_old_dentry);
lower_new_dir_dentry = dget_parent(lower_new_dentry);
trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
/* source should not be ancestor of target */
if (trap == lower_old_dentry) {
err = -EINVAL;
goto out;
}
/* target should not be ancestor of source */
if (trap == lower_new_dentry) {
err = -ENOTEMPTY;
goto out;
}
err = mnt_want_write(lower_old_path.mnt);
if (err)
goto out;
err = mnt_want_write(lower_new_path.mnt);
if (err)
goto out_drop_old_write;
err = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
lower_new_dir_dentry->d_inode, lower_new_dentry);
if (err)
goto out_err;
fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
fsstack_copy_inode_size(new_dir, lower_new_dir_dentry->d_inode);
if (new_dir != old_dir) {
fsstack_copy_attr_all(old_dir,
lower_old_dir_dentry->d_inode);
fsstack_copy_inode_size(old_dir,
lower_old_dir_dentry->d_inode);
}
out_err:
mnt_drop_write(lower_new_path.mnt);
out_drop_old_write:
mnt_drop_write(lower_old_path.mnt);
out:
unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
dput(lower_old_dir_dentry);
dput(lower_new_dir_dentry);
u2fs_put_lower_path(old_dentry, &lower_old_path);
u2fs_put_lower_path(new_dentry, &lower_new_path);
out_copyup:
return err;
}
/*
* Main rename code. This is sufficiently complex, that it's documented in
* Documentation/filesystems/unionfs/rename.txt. This routine calls
* __unionfs_rename() above to perform some of the work.
*/
static int do_unionfs_rename(struct inode *old_dir,
struct dentry *old_dentry,
struct dentry *old_parent,
struct inode *new_dir,
struct dentry *new_dentry,
struct dentry *new_parent)
{
int err = 0;
int bindex, bwh_old;
int old_bstart, old_bend;
int new_bstart, new_bend;
int do_copyup = -1;
int local_err = 0;
int eio = 0;
int revert = 0;
old_bstart = dbstart(old_dentry);
bwh_old = old_bstart;
old_bend = dbend(old_dentry);
new_bstart = dbstart(new_dentry);
new_bend = dbend(new_dentry);
/* Rename source to destination. */
err = __unionfs_rename(old_dir, old_dentry, old_parent,
new_dir, new_dentry, new_parent,
old_bstart);
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;
BUG_ON(bindex < 0);
unlink_dentry = unionfs_lower_dentry_idx(new_dentry, bindex);
if (!unlink_dentry)
continue;
unlink_dir_dentry = lock_parent(unlink_dentry);
err = is_robranch_super(old_dir->i_sb, bindex);
if (!err)
err = vfs_unlink(unlink_dir_dentry->d_inode,
unlink_dentry);
fsstack_copy_attr_times(new_parent->d_inode,
unlink_dir_dentry->d_inode);
/* propagate number of hard-links */
new_parent->d_inode->i_nlink =
unionfs_get_nlinks(new_parent->d_inode);
unlock_dir(unlink_dir_dentry);
if (!err) {
if (bindex != new_bstart) {
dput(unlink_dentry);
unionfs_set_lower_dentry_idx(new_dentry,
bindex, NULL);
}
} else if (IS_COPYUP_ERR(err)) {
do_copyup = bindex - 1;
} else if (revert) {
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_parent->d_inode,
old_dentry, old_bstart, bindex,
old_dentry->d_name.name,
old_dentry->d_name.len, NULL,
i_size_read(old_dentry->d_inode));
/* if copyup failed, try next branch to the left */
if (err)
continue;
bwh_old = bindex;
err = __unionfs_rename(old_dir, old_dentry, old_parent,
new_dir, new_dentry, new_parent,
bindex);
break;
}
}
/* make it opaque */
if (S_ISDIR(old_dentry->d_inode->i_mode)) {
err = make_dir_opaque(old_dentry, dbstart(old_dentry));
if (err)
goto revert;
}
/*
* 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)) {
if (bwh_old < 0) {
printk(KERN_ERR "unionfs: rename error (bwh_old=%d)\n",
bwh_old);
err = -EIO;
goto out;
}
err = create_whiteout(old_dentry, bwh_old);
if (err) {
/* can't fix anything now, so we exit with -EIO */
printk(KERN_ERR "unionfs: can't create a whiteout for "
"%s in rename!\n", old_dentry->d_name.name);
err = -EIO;
}
}
out:
return err;
revert:
/* Do revert here. */
local_err = unionfs_refresh_lower_dentry(new_dentry, new_parent,
old_bstart);
if (local_err) {
printk(KERN_ERR "unionfs: revert failed in rename: "
"the new refresh failed\n");
eio = -EIO;
}
local_err = unionfs_refresh_lower_dentry(old_dentry, old_parent,
old_bstart);
if (local_err) {
printk(KERN_ERR "unionfs: revert failed in rename: "
"the old refresh failed\n");
eio = -EIO;
goto revert_out;
}
if (!unionfs_lower_dentry_idx(new_dentry, bindex) ||
!unionfs_lower_dentry_idx(new_dentry, bindex)->d_inode) {
printk(KERN_ERR "unionfs: revert failed in rename: "
"the object disappeared from under us!\n");
eio = -EIO;
goto revert_out;
}
if (unionfs_lower_dentry_idx(old_dentry, bindex) &&
unionfs_lower_dentry_idx(old_dentry, bindex)->d_inode) {
printk(KERN_ERR "unionfs: revert failed in rename: "
"the object was created underneath us!\n");
eio = -EIO;
goto revert_out;
}
local_err = __unionfs_rename(new_dir, new_dentry, new_parent,
old_dir, old_dentry, old_parent,
old_bstart);
/* If we can't fix it, then we cop-out with -EIO. */
if (local_err) {
printk(KERN_ERR "unionfs: revert failed in rename!\n");
eio = -EIO;
}
local_err = unionfs_refresh_lower_dentry(new_dentry, new_parent,
bindex);
if (local_err)
eio = -EIO;
local_err = unionfs_refresh_lower_dentry(old_dentry, old_parent,
bindex);
if (local_err)
eio = -EIO;
revert_out:
if (eio)
err = eio;
return err;
}
static int unionfs_setattr(struct dentry *dentry, struct iattr *ia)
{
int err = 0;
struct dentry *hidden_dentry;
struct inode *inode = NULL;
struct inode *hidden_inode = NULL;
int bstart, bend, bindex;
int i;
int copyup = 0;
print_entry_location();
lock_dentry(dentry);
bstart = dbstart(dentry);
bend = dbend(dentry);
inode = dentry->d_inode;
for (bindex = bstart; (bindex <= bend) || (bindex == bstart); bindex++) {
hidden_dentry = dtohd_index(dentry, bindex);
if (!hidden_dentry)
continue;
BUG_ON(hidden_dentry->d_inode == NULL);
/* If the file is on a read only branch */
if (is_robranch_super(dentry->d_sb, bindex)
|| IS_RDONLY(hidden_dentry->d_inode)) {
if (copyup || (bindex != bstart))
continue;
/* Only if its the leftmost file, copyup the file */
for (i = bstart - 1; i >= 0; i--) {
size_t size = dentry->d_inode->i_size;
if (ia->ia_valid & ATTR_SIZE)
size = ia->ia_size;
err = copyup_dentry(dentry->d_parent->d_inode,
dentry, bstart, i, NULL,
size);
if (!err) {
copyup = 1;
hidden_dentry = dtohd(dentry);
break;
}
/* if error is in the leftmost f/s, pass it up */
if (i == 0)
goto out;
}
}
err = notify_change(hidden_dentry, ia);
if (err)
goto out;
break;
}
/* get the size from the first hidden inode */
hidden_inode = itohi(dentry->d_inode);
fist_checkinode(inode, "unionfs_setattr");
fist_copy_attr_all(inode, hidden_inode);
out:
unlock_dentry(dentry);
fist_checkinode(inode, "post unionfs_setattr");
print_exit_status(err);
return err;
}
static int unionfs_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *new_dentry)
{
int err = 0;
struct dentry *hidden_old_dentry = NULL;
struct dentry *hidden_new_dentry = NULL;
struct dentry *hidden_dir_dentry = NULL;
struct dentry *whiteout_dentry;
char *name = NULL;
print_entry_location();
double_lock_dentry(new_dentry, old_dentry);
hidden_new_dentry = dtohd(new_dentry);
/* check if whiteout exists in the branch of new dentry, i.e. lookup
* .wh.foo first. If present, delete it */
name = alloc_whname(new_dentry->d_name.name, new_dentry->d_name.len);
if (IS_ERR(name)) {
err = PTR_ERR(name);
goto out;
}
whiteout_dentry =
LOOKUP_ONE_LEN(name, hidden_new_dentry->d_parent,
new_dentry->d_name.len + WHLEN);
if (IS_ERR(whiteout_dentry)) {
err = PTR_ERR(whiteout_dentry);
goto out;
}
if (!whiteout_dentry->d_inode) {
DPUT(whiteout_dentry);
whiteout_dentry = NULL;
} else {
/* found a .wh.foo entry, unlink it and then call vfs_link() */
hidden_dir_dentry = lock_parent(whiteout_dentry);
if (!
(err =
is_robranch_super(new_dentry->d_sb,
dbstart(new_dentry)))) {
err =
vfs_unlink(hidden_dir_dentry->d_inode,
whiteout_dentry);
}
fist_copy_attr_times(dir, hidden_dir_dentry->d_inode);
dir->i_nlink = get_nlinks(dir);
unlock_dir(hidden_dir_dentry);
hidden_dir_dentry = NULL;
DPUT(whiteout_dentry);
if (err)
goto out;
}
if (dbstart(old_dentry) != dbstart(new_dentry)) {
hidden_new_dentry =
create_parents(dir, new_dentry, dbstart(old_dentry));
err = PTR_ERR(hidden_new_dentry);
if (IS_COPYUP_ERR(err))
goto docopyup;
if (!hidden_new_dentry || IS_ERR(hidden_new_dentry))
goto out;
}
hidden_new_dentry = dtohd(new_dentry);
hidden_old_dentry = dtohd(old_dentry);
BUG_ON(dbstart(old_dentry) != dbstart(new_dentry));
hidden_dir_dentry = lock_parent(hidden_new_dentry);
if (!(err = is_robranch(old_dentry)))
err =
vfs_link(hidden_old_dentry, hidden_dir_dentry->d_inode,
hidden_new_dentry);
unlock_dir(hidden_dir_dentry);
docopyup:
if (IS_COPYUP_ERR(err)) {
int old_bstart = dbstart(old_dentry);
int bindex;
for (bindex = old_bstart - 1; bindex >= 0; bindex--) {
err =
copyup_dentry(old_dentry->d_parent->
d_inode, old_dentry,
old_bstart, bindex, NULL,
old_dentry->d_inode->i_size);
if (!err) {
hidden_new_dentry =
create_parents(dir, new_dentry, bindex);
hidden_old_dentry = dtohd(old_dentry);
hidden_dir_dentry =
lock_parent(hidden_new_dentry);
/* do vfs_link */
err =
vfs_link(hidden_old_dentry,
hidden_dir_dentry->d_inode,
hidden_new_dentry);
unlock_dir(hidden_dir_dentry);
goto check_link;
}
}
goto out;
}
check_link:
if (err || !hidden_new_dentry->d_inode)
goto out;
/* Its a hard link, so use the same inode */
new_dentry->d_inode = IGRAB(old_dentry->d_inode);
d_instantiate(new_dentry, new_dentry->d_inode);
fist_copy_attr_all(dir, hidden_new_dentry->d_parent->d_inode);
/* propagate number of hard-links */
old_dentry->d_inode->i_nlink = get_nlinks(old_dentry->d_inode);
out:
if (!new_dentry->d_inode)
d_drop(new_dentry);
KFREE(name);
unlock_dentry(new_dentry);
unlock_dentry(old_dentry);
print_exit_status(err);
return err;
}
