/* BKL held by caller.
* dentry->d_inode->i_sem down
*/
int unionfs_removexattr(struct dentry *dentry, const char *name)
{
struct dentry *hidden_dentry = NULL;
int err = -EOPNOTSUPP;
char *encoded_name;
print_entry_location();
lock_dentry(dentry);
hidden_dentry = dtohd(dentry);
fist_dprint(8, "removexattr: name=\"%s\"\n", name);
if (hidden_dentry->d_inode->i_op->removexattr) {
encoded_name = (char *)name;
down(&hidden_dentry->d_inode->i_sem);
/* lock_kernel() already done by caller. */
err =
hidden_dentry->d_inode->i_op->removexattr(hidden_dentry,
encoded_name);
/* unlock_kernel() will be done by caller. */
up(&hidden_dentry->d_inode->i_sem);
}
unlock_dentry(dentry);
print_exit_status(err);
return err;
}
static struct dentry *lookup_whiteout(struct dentry *dentry)
{
char *whname;
int bindex = -1, bstart = -1, bend = -1;
struct dentry *parent, *hidden_parent, *wh_dentry;
whname = alloc_whname(dentry->d_name.name, dentry->d_name.len);
if (IS_ERR(whname))
return (void *)whname;
parent = GET_PARENT(dentry);
lock_dentry(parent);
bstart = dbstart(parent);
bend = dbend(parent);
wh_dentry = ERR_PTR(-ENOENT);
for (bindex = bstart; bindex <= bend; bindex++) {
hidden_parent = dtohd_index(parent, bindex);
if (!hidden_parent)
continue;
wh_dentry =
LOOKUP_ONE_LEN(whname, hidden_parent,
dentry->d_name.len + WHLEN);
if (IS_ERR(wh_dentry))
continue;
if (wh_dentry->d_inode)
break;
DPUT(wh_dentry);
wh_dentry = ERR_PTR(-ENOENT);
}
unlock_dentry(parent);
DPUT(parent);
KFREE(whname);
return wh_dentry;
}
int unionfs_readlink(struct dentry *dentry, char __user * buf, int bufsiz)
{
int err;
struct dentry *hidden_dentry;
print_entry_location();
lock_dentry(dentry);
hidden_dentry = dtohd(dentry);
fist_print_dentry("unionfs_readlink IN", dentry);
if (!hidden_dentry->d_inode->i_op ||
!hidden_dentry->d_inode->i_op->readlink) {
err = -EINVAL;
goto out;
}
err = hidden_dentry->d_inode->i_op->readlink(hidden_dentry,
buf, bufsiz);
if (err > 0)
fist_copy_attr_atime(dentry->d_inode, hidden_dentry->d_inode);
out:
unlock_dentry(dentry);
print_exit_status(err);
return err;
}
/* BKL held by caller.
* dentry->d_inode->i_sem down
*/
ssize_t unionfs_listxattr(struct dentry * dentry, char *list, size_t size)
{
struct dentry *hidden_dentry = NULL;
int err = -EOPNOTSUPP;
char *encoded_list = NULL;
print_entry_location();
lock_dentry(dentry);
hidden_dentry = dtohd(dentry);
if (hidden_dentry->d_inode->i_op->listxattr) {
encoded_list = list;
down(&hidden_dentry->d_inode->i_sem);
/* lock_kernel() already done by caller. */
err =
hidden_dentry->d_inode->i_op->listxattr(hidden_dentry,
encoded_list, size);
/* unlock_kernel() will be done by caller. */
up(&hidden_dentry->d_inode->i_sem);
}
unlock_dentry(dentry);
print_exit_status(err);
return err;
}
/* BKL held by caller.
* dentry->d_inode->i_sem down
*/
int
unionfs_setxattr(struct dentry *dentry, const char *name, const void *value,
size_t size, int flags)
{
struct dentry *hidden_dentry = NULL;
int err = -EOPNOTSUPP;
print_entry_location();
lock_dentry(dentry);
hidden_dentry = dtohd(dentry);
fist_dprint(8, "setxattr: name=\"%s\", value %lu bytes, flags=%x\n",
name, (unsigned long)size, flags);
if (hidden_dentry->d_inode->i_op->setxattr) {
down(&hidden_dentry->d_inode->i_sem);
/* lock_kernel() already done by caller. */
err = hidden_dentry->d_inode->i_op->
setxattr(hidden_dentry, name, value, size, flags);
/* unlock_kernel() will be done by caller. */
up(&hidden_dentry->d_inode->i_sem);
}
unlock_dentry(dentry);
print_exit_status(err);
return err;
}
int ll_set_dd(struct dentry *de)
{
ENTRY;
LASSERT(de != NULL);
CDEBUG(D_DENTRY, "ldd on dentry %.*s (%p) parent %p inode %p refc %d\n",
de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
atomic_read(&de->d_count));
if (de->d_fsdata == NULL) {
struct ll_dentry_data *lld;
OBD_ALLOC_PTR(lld);
if (likely(lld != NULL)) {
CFS_INIT_LIST_HEAD(&lld->lld_sa_alias);
lock_dentry(de);
if (likely(de->d_fsdata == NULL))
de->d_fsdata = lld;
else
OBD_FREE_PTR(lld);
unlock_dentry(de);
} else {
RETURN(-ENOMEM);
}
}
RETURN(0);
}
int unionfs_ioctl_rdwrbranch(struct inode *inode, unsigned int cmd,
unsigned long arg)
{
int err;
struct unionfs_rdwrbranch_args *rdwrargs = NULL;
int gen;
print_entry_location();
unionfs_write_lock(inode->i_sb);
lock_dentry(inode->i_sb->s_root);
if ((err = newputmap(inode->i_sb)))
goto out;
err = -ENOMEM;
rdwrargs = KMALLOC(sizeof(struct unionfs_rdwrbranch_args), GFP_KERNEL);
if (!rdwrargs)
goto out;
err = -EFAULT;
if (copy_from_user
(rdwrargs, (const void __user *)arg,
sizeof(struct unionfs_rdwrbranch_args)))
goto out;
err = -EINVAL;
if (rdwrargs->rwb_branch < 0
|| (rdwrargs->rwb_branch > (sbend(inode->i_sb) + 1)))
goto out;
if (rdwrargs->rwb_perms & ~(MAY_READ | MAY_WRITE | MAY_NFSRO))
goto out;
if (!(rdwrargs->rwb_perms & MAY_READ))
goto out;
set_branchperms(inode->i_sb, rdwrargs->rwb_branch, rdwrargs->rwb_perms);
atomic_inc(&stopd(inode->i_sb)->usi_generation);
gen = atomic_read(&stopd(inode->i_sb)->usi_generation);
atomic_set(&dtopd(inode->i_sb->s_root)->udi_generation, gen);
atomic_set(&itopd(inode->i_sb->s_root->d_inode)->uii_generation, gen);
err = 0;
out:
unlock_dentry(inode->i_sb->s_root);
unionfs_write_unlock(inode->i_sb);
KFREE(rdwrargs);
print_exit_status(err);
return err;
}
int unionfs_rmdir(struct inode *dir, struct dentry *dentry)
{
int err = 0;
struct unionfs_dir_state *namelist = NULL;
print_entry_location();
lock_dentry(dentry);
fist_print_dentry("IN unionfs_rmdir: ", dentry);
/* check if this unionfs directory is empty or not */
err = check_empty(dentry, &namelist);
if (err) {
goto out;
}
if (IS_SET(dir->i_sb, DELETE_WHITEOUT)) {
/* Delete the first directory. */
err = unionfs_rmdir_first(dir, dentry, namelist);
/* create whiteout */
if (!err) {
err = create_whiteout(dentry, dbstart(dentry));
} else {
int new_err;
if (dbstart(dentry) == 0)
goto out;
/* exit if the error returned was NOT -EROFS */
if (!IS_COPYUP_ERR(err))
goto out;
new_err = create_whiteout(dentry, dbstart(dentry) - 1);
if (new_err != -EEXIST)
err = new_err;
}
} else {
/* delete all. */
err = unionfs_rmdir_all(dir, dentry, namelist);
}
out:
/* call d_drop so the system "forgets" about us */
if (!err)
d_drop(dentry);
if (namelist)
free_rdstate(namelist);
unlock_dentry(dentry);
print_exit_status(err);
return err;
}
int unionfs_d_revalidate_wrap(struct dentry *dentry, struct nameidata *nd)
{
int err;
print_entry_location();
lock_dentry(dentry);
err = unionfs_d_revalidate(dentry, nd);
unlock_dentry(dentry);
print_exit_status(err);
return err;
}
void unionfs_d_release(struct dentry *dentry)
{
struct dentry *hidden_dentry;
int bindex, bstart, bend;
print_entry_location();
/* There is no reason to lock the dentry, because we have the only
* reference, but the printing functions verify that we have a lock
* on the dentry before calling dbstart, etc. */
lock_dentry(dentry);
__fist_print_dentry("unionfs_d_release IN dentry", dentry, 0);
/* this could be a negative dentry, so check first */
if (!dtopd(dentry)) {
fist_dprint(6, "dentry without private data: %*s",
dentry->d_name.len, dentry->d_name.name);
goto out;
} else if (dbstart(dentry) < 0) {
/* this is due to a failed lookup */
/* the failed lookup has a dtohd_ptr set to null,
but this is a better check */
fist_dprint(6, "dentry without hidden dentries : %*s",
dentry->d_name.len, dentry->d_name.name);
goto out_free;
}
/* Release all the hidden dentries */
bstart = dbstart(dentry);
bend = dbend(dentry);
for (bindex = bstart; bindex <= bend; bindex++) {
hidden_dentry = dtohd_index(dentry, bindex);
DPUT(hidden_dentry);
set_dtohd_index(dentry, bindex, NULL);
}
/* free private data (unionfs_dentry_info) here */
KFREE(dtohd_ptr(dentry));
dtohd_ptr(dentry) = NULL;
out_free:
/* No need to unlock it, because it is disappeared. */
#ifdef TRACKLOCK
printk("DESTROYLOCK:%p\n", dentry);
#endif
free_dentry_private_data(dtopd(dentry));
dtopd_lhs(dentry) = NULL; /* just to be safe */
out:
print_exit_location();
}
int unionfs_unlink(struct inode *dir, struct dentry *dentry)
{
int err = 0;
print_entry_location();
lock_dentry(dentry);
fist_print_dentry("IN unionfs_unlink", dentry);
if (IS_SET(dir->i_sb, DELETE_WHITEOUT))
err = unionfs_unlink_whiteout(dir, dentry);
else
err = unionfs_unlink_all(dir, dentry);
/* call d_drop so the system "forgets" about us */
if (!err)
d_drop(dentry);
unlock_dentry(dentry);
print_exit_status(err);
return err;
}
int unionfs_ioctl_queryfile(struct file *file, unsigned int cmd,
unsigned long arg)
{
int err = 0;
fd_set branchlist;
int bstart = 0, bend = 0, bindex = 0;
struct dentry *dentry, *hidden_dentry;
print_entry_location();
dentry = file->f_dentry;
lock_dentry(dentry);
if ((err = unionfs_partial_lookup(dentry)))
goto out;
bstart = dbstart(dentry);
bend = dbend(dentry);
FD_ZERO(&branchlist);
for (bindex = bstart; bindex <= bend; bindex++) {
hidden_dentry = dtohd_index(dentry, bindex);
if (!hidden_dentry)
continue;
if (hidden_dentry->d_inode)
FD_SET(bindex, &branchlist);
}
err = copy_to_user((void *)arg, &branchlist, sizeof(fd_set));
if (err) {
err = -EFAULT;
goto out;
}
out:
unlock_dentry(dentry);
err = err < 0 ? err : bend;
print_exit_status(err);
return (err);
}
/* Drop dentry if it is not used already, unhash otherwise.
Should be called with dcache lock held!
Returns: 1 if dentry was dropped, 0 if unhashed. */
int ll_drop_dentry(struct dentry *dentry)
{
lock_dentry(dentry);
if (atomic_read(&dentry->d_count) == 0) {
CDEBUG(D_DENTRY, "deleting dentry %.*s (%p) parent %p "
"inode %p\n", dentry->d_name.len,
dentry->d_name.name, dentry, dentry->d_parent,
dentry->d_inode);
dget_locked(dentry);
__d_drop(dentry);
unlock_dentry(dentry);
spin_unlock(&dcache_lock);
cfs_spin_unlock(&ll_lookup_lock);
dput(dentry);
cfs_spin_lock(&ll_lookup_lock);
spin_lock(&dcache_lock);
return 1;
}
/* disconected dentry can not be find without lookup, because we
* not need his to unhash or mark invalid. */
if (dentry->d_flags & DCACHE_DISCONNECTED) {
unlock_dentry(dentry);
RETURN (0);
}
if (!(dentry->d_flags & DCACHE_LUSTRE_INVALID)) {
CDEBUG(D_DENTRY, "unhashing dentry %.*s (%p) parent %p "
"inode %p refc %d\n", dentry->d_name.len,
dentry->d_name.name, dentry, dentry->d_parent,
dentry->d_inode, atomic_read(&dentry->d_count));
/* actually we don't unhash the dentry, rather just
* mark it inaccessible for to __d_lookup(). otherwise
* sys_getcwd() could return -ENOENT -bzzz */
dentry->d_flags |= DCACHE_LUSTRE_INVALID;
if (!dentry->d_inode || !S_ISDIR(dentry->d_inode->i_mode))
__d_drop(dentry);
}
unlock_dentry(dentry);
return 0;
}
/* BKL held by caller.
* dentry->d_inode->i_sem down
* ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
*/
ssize_t unionfs_getxattr(struct dentry *dentry, const char *name, void *value,
size_t size)
{
struct dentry *hidden_dentry = NULL;
int err = -EOPNOTSUPP;
/* Define these anyway so we don't need as much ifdef'ed code. */
char *encoded_name = NULL;
char *encoded_value = NULL;
print_entry_location();
lock_dentry(dentry);
hidden_dentry = dtohd(dentry);
fist_dprint(8, "getxattr: name=\"%s\", value %lu bytes\n", name,
(unsigned long)size);
if (hidden_dentry->d_inode->i_op->getxattr) {
encoded_name = (char *)name;
encoded_value = (char *)value;
down(&hidden_dentry->d_inode->i_sem);
/* lock_kernel() already done by caller. */
err =
hidden_dentry->d_inode->i_op->getxattr(hidden_dentry,
encoded_name,
encoded_value, size);
/* unlock_kernel() will be done by caller. */
up(&hidden_dentry->d_inode->i_sem);
}
unlock_dentry(dentry);
print_exit_status(err);
return err;
}
/* This function replicates the directory structure upto given dentry
* in the bindex branch. */
struct dentry *create_parents_named(struct inode *dir, struct dentry *dentry,
const char *name, int bindex)
{
int err;
struct dentry *child_dentry;
struct dentry *parent_dentry;
struct dentry *hidden_parent_dentry = NULL;
struct dentry *hidden_dentry = NULL;
const char *childname;
unsigned int childnamelen;
int old_kmalloc_size;
int kmalloc_size;
int num_dentry;
int count;
int old_bstart;
int old_bend;
struct dentry **path = NULL;
struct dentry **tmp_path;
print_entry_location();
verify_locked(dentry);
/* There is no sense allocating any less than the minimum. */
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
kmalloc_size = malloc_sizes[0].cs_size;
#else
kmalloc_size = 32;
#endif
num_dentry = kmalloc_size / sizeof(struct dentry *);
if ((err = is_robranch_super(dir->i_sb, bindex))) {
hidden_dentry = ERR_PTR(err);
goto out;
}
fist_print_dentry("IN: create_parents_named", dentry);
fist_dprint(8, "name = %s\n", name);
old_bstart = dbstart(dentry);
old_bend = dbend(dentry);
path = (struct dentry **)KMALLOC(kmalloc_size, GFP_KERNEL);
memset(path, 0, kmalloc_size);
/* assume the negative dentry of unionfs as the parent dentry */
parent_dentry = dentry;
count = 0;
/* This loop finds the first parent that exists in the given branch.
* We start building the directory structure from there. At the end
* of the loop, the following should hold:
* child_dentry is the first nonexistent child
* parent_dentry is the first existent parent
* path[0] is the = deepest child
* path[count] is the first child to create
*/
do {
child_dentry = parent_dentry;
/* find the parent directory dentry in unionfs */
parent_dentry = child_dentry->d_parent;
lock_dentry(parent_dentry);
/* find out the hidden_parent_dentry in the given branch */
hidden_parent_dentry = dtohd_index(parent_dentry, bindex);
/* store the child dentry */
path[count++] = child_dentry;
if (count == num_dentry) {
old_kmalloc_size = kmalloc_size;
kmalloc_size *= 2;
num_dentry = kmalloc_size / sizeof(struct dentry *);
tmp_path =
(struct dentry **)KMALLOC(kmalloc_size, GFP_KERNEL);
if (!tmp_path) {
hidden_dentry = ERR_PTR(-ENOMEM);
goto out;
}
memset(tmp_path, 0, kmalloc_size);
memcpy(tmp_path, path, old_kmalloc_size);
KFREE(path);
path = tmp_path;
tmp_path = NULL;
}
} while (!hidden_parent_dentry);
count--;
/* This is basically while(child_dentry != dentry). This loop is
* horrible to follow and should be replaced with cleaner code. */
while (1) {
PASSERT(child_dentry);
PASSERT(parent_dentry);
PASSERT(parent_dentry->d_inode);
// get hidden parent dir in the current branch
hidden_parent_dentry = dtohd_index(parent_dentry, bindex);
unlock_dentry(parent_dentry);
PASSERT(hidden_parent_dentry);
PASSERT(hidden_parent_dentry->d_inode);
// init the values to lookup
childname = child_dentry->d_name.name;
childnamelen = child_dentry->d_name.len;
if (child_dentry != dentry) {
// lookup child in the underlying file system
hidden_dentry =
LOOKUP_ONE_LEN(childname, hidden_parent_dentry,
childnamelen);
if (IS_ERR(hidden_dentry))
goto out;
} else {
int loop_start;
int loop_end;
int new_bstart = -1;
int new_bend = -1;
int i;
/* is the name a whiteout of the childname ? */
//lookup the whiteout child in the underlying file system
hidden_dentry =
LOOKUP_ONE_LEN(name, hidden_parent_dentry,
strlen(name));
if (IS_ERR(hidden_dentry))
goto out;
/* Replace the current dentry (if any) with the new one. */
DPUT(dtohd_index(dentry, bindex));
set_dtohd_index(dentry, bindex, hidden_dentry);
loop_start =
(old_bstart < bindex) ? old_bstart : bindex;
loop_end = (old_bend > bindex) ? old_bend : bindex;
/* This loop sets the bstart and bend for the new
* dentry by traversing from left to right.
* It also dputs all negative dentries except
* bindex (the newly looked dentry
*/
for (i = loop_start; i <= loop_end; i++) {
if (!dtohd_index(dentry, i))
continue;
if (i == bindex) {
new_bend = i;
if (new_bstart < 0)
new_bstart = i;
continue;
}
if (!dtohd_index(dentry, i)->d_inode) {
DPUT(dtohd_index(dentry, i));
set_dtohd_index(dentry, i, NULL);
} else {
if (new_bstart < 0)
new_bstart = i;
new_bend = i;
}
}
if (new_bstart < 0)
new_bstart = bindex;
if (new_bend < 0)
new_bend = bindex;
set_dbstart(dentry, new_bstart);
set_dbend(dentry, new_bend);
break;
}
if (hidden_dentry->d_inode) {
/* since this already exists we dput to avoid
* multiple references on the same dentry */
DPUT(hidden_dentry);
} else {
uid_t saved_uid = current->fsuid;
gid_t saved_gid = current->fsgid;
/* its a negative dentry, create a new dir */
hidden_parent_dentry = lock_parent(hidden_dentry);
current->fsuid = hidden_parent_dentry->d_inode->i_uid;
current->fsgid = hidden_parent_dentry->d_inode->i_gid;
err = vfs_mkdir(hidden_parent_dentry->d_inode,
hidden_dentry, S_IRWXUGO);
current->fsuid = saved_uid;
current->fsgid = saved_gid;
unlock_dir(hidden_parent_dentry);
if (err || !hidden_dentry->d_inode) {
DPUT(hidden_dentry);
hidden_dentry = ERR_PTR(err);
goto out;
}
err =
copyup_permissions(dir->i_sb, child_dentry,
hidden_dentry);
if (err) {
DPUT(hidden_dentry);
hidden_dentry = ERR_PTR(err);
goto out;
}
set_itohi_index(child_dentry->d_inode, bindex,
igrab(hidden_dentry->d_inode));
if (ibstart(child_dentry->d_inode) > bindex)
ibstart(child_dentry->d_inode) = bindex;
if (ibend(child_dentry->d_inode) < bindex)
ibend(child_dentry->d_inode) = bindex;
set_dtohd_index(child_dentry, bindex, hidden_dentry);
if (dbstart(child_dentry) > bindex)
set_dbstart(child_dentry, bindex);
if (dbend(child_dentry) < bindex)
set_dbend(child_dentry, bindex);
}
parent_dentry = child_dentry;
child_dentry = path[--count];
}
out:
KFREE(path);
fist_print_dentry("OUT: create_parents_named", dentry);
print_exit_pointer(hidden_dentry);
return hidden_dentry;
}
/* This must be called with the super block already locked. */
int unionfs_ioctl_delbranch(struct super_block *sb, unsigned long arg)
{
struct dentry *hidden_dentry;
struct inode *hidden_inode;
struct super_block *hidden_sb;
struct vfsmount *hidden_mnt;
struct dentry *root_dentry;
struct inode *root_inode;
int err = 0;
int pmindex, i, gen;
print_entry("branch = %lu ", arg);
lock_dentry(sb->s_root);
err = -EBUSY;
if (sbmax(sb) == 1)
goto out;
err = -EINVAL;
if (arg < 0 || arg > stopd(sb)->b_end)
goto out;
err = -EBUSY;
if (branch_count(sb, arg))
goto out;
if ((err = newputmap(sb)))
goto out;
pmindex = stopd(sb)->usi_lastputmap;
pmindex -= stopd(sb)->usi_firstputmap;
atomic_inc(&stopd(sb)->usi_generation);
gen = atomic_read(&stopd(sb)->usi_generation);
root_dentry = sb->s_root;
root_inode = sb->s_root->d_inode;
hidden_dentry = dtohd_index(root_dentry, arg);
hidden_mnt = stohiddenmnt_index(sb, arg);
hidden_inode = itohi_index(root_inode, arg);
hidden_sb = stohs_index(sb, arg);
DPUT(hidden_dentry);
iput(hidden_inode);
mntput(hidden_mnt);
for (i = arg; i <= (sbend(sb) - 1); i++) {
set_branch_count(sb, i, branch_count(sb, i + 1));
set_stohiddenmnt_index(sb, i, stohiddenmnt_index(sb, i + 1));
set_stohs_index(sb, i, stohs_index(sb, i + 1));
set_branchperms(sb, i, branchperms(sb, i + 1));
set_dtohd_index(root_dentry, i,
dtohd_index(root_dentry, i + 1));
set_itohi_index(root_inode, i, itohi_index(root_inode, i + 1));
stopd(sb)->usi_putmaps[pmindex]->map[i + 1] = i;
}
set_dtohd_index(root_dentry, sbend(sb), NULL);
set_itohi_index(root_inode, sbend(sb), NULL);
set_stohiddenmnt_index(sb, sbend(sb), NULL);
set_stohs_index(sb, sbend(sb), NULL);
stopd(sb)->b_end--;
set_dbend(root_dentry, dbend(root_dentry) - 1);
dtopd(root_dentry)->udi_bcount--;
itopd(root_inode)->b_end--;
atomic_set(&dtopd(root_dentry)->udi_generation, gen);
atomic_set(&itopd(root_inode)->uii_generation, gen);
fixputmaps(sb);
/* This doesn't open a file, so we might have to free the map here. */
if (atomic_read(&stopd(sb)->usi_putmaps[pmindex]->count) == 0) {
KFREE(stopd(sb)->usi_putmaps[pmindex]);
stopd(sb)->usi_putmaps[pmindex] = NULL;
}
out:
unlock_dentry(sb->s_root);
print_exit_status(err);
return err;
}
int unionfs_ioctl_addbranch(struct inode *inode, unsigned int cmd,
unsigned long arg)
{
int err;
struct unionfs_addbranch_args *addargs = NULL;
struct nameidata nd;
char *path = NULL;
int gen;
int i;
int count;
int pobjects;
struct vfsmount **new_hidden_mnt = NULL;
struct inode **new_uii_inode = NULL;
struct dentry **new_udi_dentry = NULL;
struct super_block **new_usi_sb = NULL;
int *new_branchperms = NULL;
atomic_t *new_counts = NULL;
print_entry_location();
err = -ENOMEM;
addargs = KMALLOC(sizeof(struct unionfs_addbranch_args), GFP_UNIONFS);
if (!addargs)
goto out;
err = -EFAULT;
if (copy_from_user
(addargs, (void *)arg, sizeof(struct unionfs_addbranch_args)))
goto out;
err = -EINVAL;
if (addargs->ab_perms & ~(MAY_READ | MAY_WRITE))
goto out;
if (!(addargs->ab_perms & MAY_READ))
goto out;
err = -E2BIG;
if (sbend(inode->i_sb) > FD_SETSIZE)
goto out;
err = -ENOMEM;
if (!(path = getname(addargs->ab_path)))
goto out;
err = path_lookup(path, LOOKUP_FOLLOW, &nd);
RECORD_PATH_LOOKUP(&nd);
if (err)
goto out;
if ((err = check_branch(&nd))) {
path_release(&nd);
RECORD_PATH_RELEASE(&nd);
goto out;
}
unionfs_write_lock(inode->i_sb);
lock_dentry(inode->i_sb->s_root);
err = -EINVAL;
if (addargs->ab_branch < 0
|| (addargs->ab_branch > (sbend(inode->i_sb) + 1)))
goto out;
if ((err = newputmap(inode->i_sb)))
goto out;
stopd(inode->i_sb)->b_end++;
dtopd(inode->i_sb->s_root)->udi_bcount++;
set_dbend(inode->i_sb->s_root, dbend(inode->i_sb->s_root) + 1);
itopd(inode->i_sb->s_root->d_inode)->b_end++;
atomic_inc(&stopd(inode->i_sb)->usi_generation);
gen = atomic_read(&stopd(inode->i_sb)->usi_generation);
pobjects = (sbend(inode->i_sb) + 1) - UNIONFS_INLINE_OBJECTS;
if (pobjects > 0) {
/* Reallocate the dynamic structures. */
new_hidden_mnt =
KMALLOC(sizeof(struct vfsmount *) * pobjects, GFP_UNIONFS);
new_udi_dentry =
KMALLOC(sizeof(struct dentry *) * pobjects, GFP_UNIONFS);
new_uii_inode =
KMALLOC(sizeof(struct inode *) * pobjects, GFP_UNIONFS);
new_usi_sb =
KMALLOC(sizeof(struct super_block *) * pobjects,
GFP_UNIONFS);
new_counts = KMALLOC(sizeof(atomic_t) * pobjects, GFP_UNIONFS);
new_branchperms = KMALLOC(sizeof(int) * pobjects, GFP_UNIONFS);
if (!new_hidden_mnt || !new_udi_dentry || !new_uii_inode
|| !new_counts || !new_usi_sb || !new_branchperms) {
err = -ENOMEM;
goto out;
}
memset(new_hidden_mnt, 0, sizeof(struct vfsmount *) * pobjects);
memset(new_udi_dentry, 0, sizeof(struct dentry *) * pobjects);
memset(new_uii_inode, 0, sizeof(struct inode *) * pobjects);
memset(new_usi_sb, 0, sizeof(struct super_block *) * pobjects);
memset(new_branchperms, 0, sizeof(int) * pobjects);
}
/* Copy the in-place values to our new structure. */
for (i = UNIONFS_INLINE_OBJECTS; i < addargs->ab_branch; i++) {
int j = i - UNIONFS_INLINE_OBJECTS;
count = branch_count(inode->i_sb, i);
atomic_set(&(new_counts[j]), count);
new_branchperms[j] = branchperms(inode->i_sb, i);
new_hidden_mnt[j] = stohiddenmnt_index(inode->i_sb, i);
new_usi_sb[j] = stohs_index(inode->i_sb, i);
new_udi_dentry[j] = dtohd_index(inode->i_sb->s_root, i);
new_uii_inode[j] = itohi_index(inode->i_sb->s_root->d_inode, i);
}
/* Shift the ends to the right (only handle reallocated bits). */
for (i = sbend(inode->i_sb) - 1; i >= (int)addargs->ab_branch; i--) {
int j = i + 1;
int perms;
struct vfsmount *hm;
struct super_block *hs;
struct dentry *hd;
struct inode *hi;
int pmindex;
count = branch_count(inode->i_sb, i);
perms = branchperms(inode->i_sb, i);
hm = stohiddenmnt_index(inode->i_sb, i);
hs = stohs_index(inode->i_sb, i);
hd = dtohd_index(inode->i_sb->s_root, i);
hi = itohi_index(inode->i_sb->s_root->d_inode, i);
/* Update the newest putmap, so it is correct for later. */
pmindex = stopd(inode->i_sb)->usi_lastputmap;
pmindex -= stopd(inode->i_sb)->usi_firstputmap;
stopd(inode->i_sb)->usi_putmaps[pmindex]->map[i] = j;
if (j >= UNIONFS_INLINE_OBJECTS) {
j -= UNIONFS_INLINE_OBJECTS;
atomic_set(&(new_counts[j]), count);
new_branchperms[j] = perms;
new_hidden_mnt[j] = hm;
new_usi_sb[j] = hs;
new_udi_dentry[j] = hd;
new_uii_inode[j] = hi;
} else {
set_branch_count(inode->i_sb, j, count);
set_branchperms(inode->i_sb, j, perms);
set_stohiddenmnt_index(inode->i_sb, j, hm);
set_stohs_index(inode->i_sb, j, hs);
set_dtohd_index(inode->i_sb->s_root, j, hd);
set_itohi_index(inode->i_sb->s_root->d_inode, j, hi);
}
}
/* Now we can free the old ones. */
KFREE(dtopd(inode->i_sb->s_root)->udi_dentry_p);
KFREE(itopd(inode->i_sb->s_root->d_inode)->uii_inode_p);
KFREE(stopd(inode->i_sb)->usi_hidden_mnt_p);
KFREE(stopd(inode->i_sb)->usi_sb_p);
KFREE(stopd(inode->i_sb)->usi_sbcount_p);
KFREE(stopd(inode->i_sb)->usi_branchperms_p);
/* Update the real pointers. */
dtohd_ptr(inode->i_sb->s_root) = new_udi_dentry;
itohi_ptr(inode->i_sb->s_root->d_inode) = new_uii_inode;
stohiddenmnt_ptr(inode->i_sb) = new_hidden_mnt;
stohs_ptr(inode->i_sb) = new_usi_sb;
stopd(inode->i_sb)->usi_sbcount_p = new_counts;
stopd(inode->i_sb)->usi_branchperms_p = new_branchperms;
/* Re-NULL the new ones so we don't try to free them. */
new_hidden_mnt = NULL;
new_udi_dentry = NULL;
new_usi_sb = NULL;
new_uii_inode = NULL;
new_counts = NULL;
new_branchperms = NULL;
/* Put the new dentry information into it's slot. */
set_dtohd_index(inode->i_sb->s_root, addargs->ab_branch, nd.dentry);
set_itohi_index(inode->i_sb->s_root->d_inode, addargs->ab_branch,
igrab(nd.dentry->d_inode));
set_branchperms(inode->i_sb, addargs->ab_branch, addargs->ab_perms);
set_branch_count(inode->i_sb, addargs->ab_branch, 0);
set_stohiddenmnt_index(inode->i_sb, addargs->ab_branch, nd.mnt);
set_stohs_index(inode->i_sb, addargs->ab_branch, nd.dentry->d_sb);
atomic_set(&dtopd(inode->i_sb->s_root)->udi_generation, gen);
atomic_set(&itopd(inode->i_sb->s_root->d_inode)->uii_generation, gen);
fixputmaps(inode->i_sb);
out:
unlock_dentry(inode->i_sb->s_root);
unionfs_write_unlock(inode->i_sb);
KFREE(new_hidden_mnt);
KFREE(new_udi_dentry);
KFREE(new_uii_inode);
KFREE(new_usi_sb);
KFREE(new_counts);
KFREE(new_branchperms);
KFREE(addargs);
if (path)
putname(path);
print_exit_status(err);
return err;
}
static int unionfs_mkdir(struct inode *parent, struct dentry *dentry, int mode)
{
int err = 0;
struct dentry *hidden_dentry = NULL, *whiteout_dentry = NULL;
struct dentry *hidden_parent_dentry = NULL;
int bindex = 0, bstart;
char *name = NULL;
int whiteout_unlinked = 0;
uid_t saved_uid = current->fsuid;
gid_t saved_gid = current->fsgid;
print_entry_location();
lock_dentry(dentry);
fist_print_dentry("IN unionfs_mkdir", dentry);
bstart = dbstart(dentry);
hidden_dentry = dtohd(dentry);
// check if whiteout exists in this branch, i.e. lookup .wh.foo first
name = alloc_whname(dentry->d_name.name, dentry->d_name.len);
if (IS_ERR(name)) {
err = PTR_ERR(name);
goto out;
}
whiteout_dentry =
LOOKUP_ONE_LEN(name, hidden_dentry->d_parent,
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 {
hidden_parent_dentry = lock_parent(whiteout_dentry);
/* Set the uid and gid to trick the fs into allowing us to create
* the file */
current->fsuid = hidden_parent_dentry->d_inode->i_uid;
current->fsgid = hidden_parent_dentry->d_inode->i_gid;
//found a.wh.foo entry, remove it then do vfs_mkdir
if (!(err = is_robranch_super(dentry->d_sb, bstart))) {
err =
vfs_unlink(hidden_parent_dentry->d_inode,
whiteout_dentry);
}
DPUT(whiteout_dentry);
current->fsuid = saved_uid;
current->fsgid = saved_gid;
unlock_dir(hidden_parent_dentry);
if (err) {
/* exit if the error returned was NOT -EROFS */
if (!IS_COPYUP_ERR(err))
goto out;
bstart--;
} else {
whiteout_unlinked = 1;
}
}
for (bindex = bstart; bindex >= 0; bindex--) {
hidden_dentry = dtohd_index(dentry, bindex);
if (!hidden_dentry) {
hidden_dentry = create_parents(parent, dentry, bindex);
if (!hidden_dentry || IS_ERR(hidden_dentry)) {
fist_dprint(8,
"hidden dentry NULL for bindex = %d\n",
bindex);
continue;
}
}
hidden_parent_dentry = lock_parent(hidden_dentry);
if (IS_ERR(hidden_parent_dentry)) {
err = PTR_ERR(hidden_parent_dentry);
goto out;
}
if (!(err = is_robranch_super(dentry->d_sb, bindex))) {
err =
vfs_mkdir(hidden_parent_dentry->d_inode,
hidden_dentry, mode);
}
unlock_dir(hidden_parent_dentry);
/* XXX this could potentially return a negative hidden_dentry! */
if (err || !hidden_dentry->d_inode) {
/* break out of for loop if error returned was NOT -EROFS */
if (!IS_COPYUP_ERR(err))
break;
} else {
int i;
int bend = dbend(dentry);
for (i = bindex + 1; i < bend; i++) {
if (dtohd_index(dentry, i)) {
DPUT(dtohd_index(dentry, i));
set_dtohd_index(dentry, i, NULL);
}
}
bend = bindex;
set_dbend(dentry, bend);
err = unionfs_interpose(dentry, parent->i_sb, 0);
if (!err) {
fist_copy_attr_timesizes(parent,
hidden_parent_dentry->
d_inode);
/* update number of links on parent directory */
parent->i_nlink = get_nlinks(parent);
}
whiteout_dentry = LOOKUP_ONE_LEN(UNIONFS_DIR_OPAQUE,
hidden_dentry,
sizeof
(UNIONFS_DIR_OPAQUE) -
1);
if (IS_ERR(whiteout_dentry)) {
err = PTR_ERR(whiteout_dentry);
goto out;
}
down(&hidden_dentry->d_inode->i_sem);
err = vfs_create(hidden_dentry->d_inode,
whiteout_dentry, 0600, NULL);
up(&hidden_dentry->d_inode->i_sem);
DPUT(whiteout_dentry);
if (err) {
fist_dprint(8,
"mkdir: error creating directory override entry: %d\n",
err);
goto out;
}
break;
}
}
out:
if (!dentry->d_inode)
d_drop(dentry);
KFREE(name);
fist_print_dentry("OUT unionfs_mkdir :", dentry);
unlock_dentry(dentry);
print_exit_status(err);
return err;
}
static int unionfs_mknod(struct inode *dir, struct dentry *dentry, int mode,
dev_t dev)
{
int err = 0;
struct dentry *hidden_dentry = NULL, *whiteout_dentry = NULL;
struct dentry *hidden_parent_dentry = NULL;
int bindex = 0, bstart;
char *name = NULL;
int whiteout_unlinked = 0;
print_entry_location();
lock_dentry(dentry);
fist_print_dentry("IN unionfs_mknod", dentry);
bstart = dbstart(dentry);
hidden_dentry = dtohd(dentry);
// check if whiteout exists in this branch, i.e. lookup .wh.foo first
name = alloc_whname(dentry->d_name.name, dentry->d_name.len);
if (IS_ERR(name)) {
err = PTR_ERR(name);
goto out;
}
whiteout_dentry =
LOOKUP_ONE_LEN(name, hidden_dentry->d_parent,
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 .wh.foo, unlink it */
hidden_parent_dentry = lock_parent(whiteout_dentry);
//found a.wh.foo entry, remove it then do vfs_mkdir
if (!(err = is_robranch_super(dentry->d_sb, bstart)))
err = vfs_unlink(hidden_parent_dentry->d_inode,
whiteout_dentry);
DPUT(whiteout_dentry);
unlock_dir(hidden_parent_dentry);
if (err) {
if (!IS_COPYUP_ERR(err))
goto out;
bstart--;
} else {
whiteout_unlinked = 1;
}
}
for (bindex = bstart; bindex >= 0; bindex--) {
hidden_dentry = dtohd_index(dentry, bindex);
if (!hidden_dentry) {
hidden_dentry = create_parents(dir, dentry, bindex);
if (!hidden_dentry || IS_ERR(hidden_dentry)) {
fist_dprint(8,
"hidden dentry NULL for bindex = %d\n",
bindex);
continue;
}
}
hidden_parent_dentry = lock_parent(hidden_dentry);
if (IS_ERR(hidden_parent_dentry)) {
err = PTR_ERR(hidden_parent_dentry);
goto out;
}
if (!(err = is_robranch_super(dentry->d_sb, bindex))) {
err = vfs_mknod(hidden_parent_dentry->d_inode,
hidden_dentry, mode, dev);
}
/* XXX this could potentially return a negative hidden_dentry! */
if (err || !hidden_dentry->d_inode) {
unlock_dir(hidden_parent_dentry);
/* break out of for, if error was NOT -EROFS */
if (!IS_COPYUP_ERR(err))
break;
} else {
err = unionfs_interpose(dentry, dir->i_sb, 0);
if (!err) {
fist_copy_attr_timesizes(dir,
hidden_parent_dentry->
d_inode);
/* update number of links on parent directory */
dir->i_nlink = get_nlinks(dir);
}
unlock_dir(hidden_parent_dentry);
break;
}
}
out:
if (!dentry->d_inode)
d_drop(dentry);
if (name) {
KFREE(name);
}
fist_print_dentry("OUT unionfs_mknod :", dentry);
unlock_dentry(dentry);
print_exit_status(err);
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;
}
int unionfs_rmdir(struct inode *dir, struct dentry *dentry)
{
int err = 0;
struct unionfs_dir_state *namelist = NULL;
print_entry_location();
lock_dentry(dentry);
fist_print_dentry("IN unionfs_rmdir: ", dentry);
/* check if this unionfs directory is empty or not */
err = check_empty(dentry, &namelist);
if (err) {
#if 0
/* vfs_rmdir(our caller) unhashed the dentry. This will recover
* the Unionfs inode number for the directory itself, but the
* children are already lost. It seems that tmpfs manages its
* way around this by upping the refcount on everything.
*
* Even if we do this, we still lose the inode numbers of the
* children. The best way to fix this is to fix the VFS (or
* use persistent inode maps). */
if (d_unhashed(dentry))
d_rehash(dentry);
#endif
goto out;
}
#ifdef UNIONFS_DELETE_ALL
if (IS_SET(dir->i_sb, DELETE_ALL)) {
/* delete all. */
err = unionfs_rmdir_all(dir, dentry, namelist);
} else { /* Delete the first directory. */
#endif
err = unionfs_rmdir_first(dir, dentry, namelist);
/* create whiteout */
if (!err) {
err = create_whiteout(dentry, dbstart(dentry));
} else {
int new_err;
if (dbstart(dentry) == 0)
goto out;
/* exit if the error returned was NOT -EROFS */
if (!IS_COPYUP_ERR(err))
goto out;
new_err = create_whiteout(dentry, dbstart(dentry) - 1);
if (new_err != -EEXIST)
err = new_err;
}
#ifdef UNIONFS_DELETE_ALL
}
#endif
out:
/* call d_drop so the system "forgets" about us */
if (!err)
d_drop(dentry);
if (namelist)
free_rdstate(namelist);
unlock_dentry(dentry);
print_exit_status(err);
return err;
}
static int unionfs_create(struct inode *parent, struct dentry *dentry,
int mode, struct nameidata *nd)
{
int err = 0;
struct dentry *hidden_dentry = NULL;
struct dentry *whiteout_dentry = NULL;
struct dentry *new_hidden_dentry;
struct dentry *hidden_parent_dentry = NULL;
int bindex = 0, bstart;
char *name = NULL;
print_entry_location();
lock_dentry(dentry);
fist_print_dentry("IN unionfs_create", dentry);
/* We start out in the leftmost branch. */
bstart = dbstart(dentry);
hidden_dentry = dtohd(dentry);
/* check if whiteout exists in this branch, i.e. lookup .wh.foo first */
name = alloc_whname(dentry->d_name.name, dentry->d_name.len);
if (IS_ERR(name)) {
err = PTR_ERR(name);
goto out;
}
whiteout_dentry =
LOOKUP_ONE_LEN(name, hidden_dentry->d_parent,
dentry->d_name.len + WHLEN);
if (IS_ERR(whiteout_dentry)) {
err = PTR_ERR(whiteout_dentry);
whiteout_dentry = NULL;
goto out;
}
if (whiteout_dentry->d_inode) {
/* .wh.foo has been found. */
/* First truncate it and then rename it to foo (hence having
* the same overall effect as a normal create.
*
* XXX: This is not strictly correct. If we have unlinked the
* file and it still has a reference count, then we should
* actually unlink the whiteout so that user's data isn't
* hosed over.
*/
struct dentry *hidden_dir_dentry;
struct iattr newattrs;
down(&whiteout_dentry->d_inode->i_sem);
newattrs.ia_valid = ATTR_CTIME | ATTR_MODE | ATTR_ATIME
| ATTR_MTIME | ATTR_UID | ATTR_GID | ATTR_FORCE
| ATTR_KILL_SUID | ATTR_KILL_SGID;
newattrs.ia_mode = mode & ~current->fs->umask;
newattrs.ia_uid = current->fsuid;
newattrs.ia_gid = current->fsgid;
if (whiteout_dentry->d_inode->i_size != 0) {
newattrs.ia_valid |= ATTR_SIZE;
newattrs.ia_size = 0;
}
err = notify_change(whiteout_dentry, &newattrs);
up(&whiteout_dentry->d_inode->i_sem);
if (err)
printk(KERN_WARNING
"unionfs: %s:%d: notify_change failed: %d, ignoring..\n",
__FILE__, __LINE__, err);
new_hidden_dentry = dtohd(dentry);
DGET(new_hidden_dentry);
hidden_dir_dentry = GET_PARENT(whiteout_dentry);
lock_rename(hidden_dir_dentry, hidden_dir_dentry);
if (!(err = is_robranch_super(dentry->d_sb, bstart))) {
err =
vfs_rename(hidden_dir_dentry->d_inode,
whiteout_dentry,
hidden_dir_dentry->d_inode,
new_hidden_dentry);
}
if (!err) {
fist_copy_attr_timesizes(parent,
new_hidden_dentry->d_parent->
d_inode);
parent->i_nlink = get_nlinks(parent);
}
unlock_rename(hidden_dir_dentry, hidden_dir_dentry);
DPUT(hidden_dir_dentry);
DPUT(new_hidden_dentry);
if (err) {
/* exit if the error returned was NOT -EROFS */
if (!IS_COPYUP_ERR(err))
goto out;
/* We were not able to create the file in this branch,
* so, we try to create it in one branch to left
*/
bstart--;
} else {
/* reset the unionfs dentry to point to the .wh.foo entry. */
/* Discard any old reference. */
DPUT(dtohd(dentry));
/* Trade one reference to another. */
set_dtohd_index(dentry, bstart, whiteout_dentry);
whiteout_dentry = NULL;
err = unionfs_interpose(dentry, parent->i_sb, 0);
goto out;
}
}
for (bindex = bstart; bindex >= 0; bindex--) {
hidden_dentry = dtohd_index(dentry, bindex);
if (!hidden_dentry) {
/* if hidden_dentry is NULL, create the entire
* dentry directory structure in branch 'bindex'.
* hidden_dentry will NOT be null when bindex == bstart
* because lookup passed as a negative unionfs dentry
* pointing to a lone negative underlying dentry */
hidden_dentry = create_parents(parent, dentry, bindex);
if (!hidden_dentry || IS_ERR(hidden_dentry)) {
if (IS_ERR(hidden_dentry))
err = PTR_ERR(hidden_dentry);
continue;
}
}
fist_checkinode(parent, "unionfs_create");
hidden_parent_dentry = lock_parent(hidden_dentry);
if (IS_ERR(hidden_parent_dentry)) {
err = PTR_ERR(hidden_parent_dentry);
goto out;
}
/* We shouldn't create things in a read-only branch. */
if (!(err = is_robranch_super(dentry->d_sb, bindex))) {
//DQ: vfs_create has a different prototype in 2.6
err = vfs_create(hidden_parent_dentry->d_inode,
hidden_dentry, mode, nd);
}
if (err || !hidden_dentry->d_inode) {
unlock_dir(hidden_parent_dentry);
/* break out of for loop if the error wasn't -EROFS */
if (!IS_COPYUP_ERR(err))
break;
} else {
err = unionfs_interpose(dentry, parent->i_sb, 0);
if (!err) {
fist_copy_attr_timesizes(parent,
hidden_parent_dentry->
d_inode);
/* update number of links on parent directory */
parent->i_nlink = get_nlinks(parent);
}
unlock_dir(hidden_parent_dentry);
break;
}
}
out:
DPUT(whiteout_dentry);
KFREE(name);
fist_print_dentry("OUT unionfs_create :", dentry);
unlock_dentry(dentry);
print_exit_status(err);
return err;
}
int unionfs_ioctl_addbranch(struct inode *inode, unsigned int cmd,
unsigned long arg)
{
int err;
struct unionfs_addbranch_args *addargs = NULL;
struct nameidata nd;
char *path = NULL;
int gen;
int i;
int pobjects;
struct unionfs_usi_data *new_data = NULL;
struct dentry **new_udi_dentry = NULL;
struct inode **new_uii_inode = NULL;
struct dentry *root = NULL;
struct dentry *hidden_root = NULL;
print_entry_location();
err = -ENOMEM;
addargs = KMALLOC(sizeof(struct unionfs_addbranch_args), GFP_KERNEL);
if (!addargs)
goto out;
err = -EFAULT;
if (copy_from_user
(addargs, (const void __user *)arg,
sizeof(struct unionfs_addbranch_args)))
goto out;
err = -EINVAL;
if (addargs->ab_perms & ~(MAY_READ | MAY_WRITE | MAY_NFSRO))
goto out;
if (!(addargs->ab_perms & MAY_READ))
goto out;
err = -E2BIG;
if (sbend(inode->i_sb) > FD_SETSIZE)
goto out;
err = -ENOMEM;
if (!(path = getname((const char __user *)addargs->ab_path)))
goto out;
err = path_lookup(path, LOOKUP_FOLLOW, &nd);
RECORD_PATH_LOOKUP(&nd);
if (err)
goto out;
if ((err = check_branch(&nd))) {
path_release(&nd);
RECORD_PATH_RELEASE(&nd);
goto out;
}
unionfs_write_lock(inode->i_sb);
lock_dentry(inode->i_sb->s_root);
root = inode->i_sb->s_root;
for (i = dbstart(inode->i_sb->s_root); i <= dbend(inode->i_sb->s_root);
i++) {
hidden_root = dtohd_index(root, i);
if (is_branch_overlap(hidden_root, nd.dentry)) {
err = -EINVAL;
goto out;
}
}
err = -EINVAL;
if (addargs->ab_branch < 0
|| (addargs->ab_branch > (sbend(inode->i_sb) + 1)))
goto out;
if ((err = newputmap(inode->i_sb)))
goto out;
stopd(inode->i_sb)->b_end++;
dtopd(inode->i_sb->s_root)->udi_bcount++;
set_dbend(inode->i_sb->s_root, dbend(inode->i_sb->s_root) + 1);
itopd(inode->i_sb->s_root->d_inode)->b_end++;
atomic_inc(&stopd(inode->i_sb)->usi_generation);
gen = atomic_read(&stopd(inode->i_sb)->usi_generation);
pobjects = sbend(inode->i_sb) + 1;
/* Reallocate the dynamic structures. */
new_data = alloc_new_data(pobjects);
new_udi_dentry = alloc_new_dentries(pobjects);
new_uii_inode = KZALLOC(sizeof(struct inode *) * pobjects, GFP_KERNEL);
if (!new_udi_dentry || !new_uii_inode || !new_data) {
err = -ENOMEM;
goto out;
}
/* Copy the in-place values to our new structure. */
for (i = 0; i < addargs->ab_branch; i++) {
atomic_set(&(new_data[i].sbcount),
branch_count(inode->i_sb, i));
new_data[i].branchperms = branchperms(inode->i_sb, i);
new_data[i].hidden_mnt = stohiddenmnt_index(inode->i_sb, i);
new_data[i].sb = stohs_index(inode->i_sb, i);
new_udi_dentry[i] = dtohd_index(inode->i_sb->s_root, i);
new_uii_inode[i] = itohi_index(inode->i_sb->s_root->d_inode, i);
}
/* Shift the ends to the right (only handle reallocated bits). */
for (i = sbend(inode->i_sb) - 1; i >= (int)addargs->ab_branch; i--) {
int j = i + 1;
int pmindex;
atomic_set(&new_data[j].sbcount, branch_count(inode->i_sb, i));
new_data[j].branchperms = branchperms(inode->i_sb, i);
new_data[j].hidden_mnt = stohiddenmnt_index(inode->i_sb, i);
new_data[j].sb = stohs_index(inode->i_sb, i);
new_udi_dentry[j] = dtohd_index(inode->i_sb->s_root, i);
new_uii_inode[j] = itohi_index(inode->i_sb->s_root->d_inode, i);
/* Update the newest putmap, so it is correct for later. */
pmindex = stopd(inode->i_sb)->usi_lastputmap;
pmindex -= stopd(inode->i_sb)->usi_firstputmap;
stopd(inode->i_sb)->usi_putmaps[pmindex]->map[i] = j;
}
/* Now we can free the old ones. */
KFREE(dtopd(inode->i_sb->s_root)->udi_dentry);
KFREE(itopd(inode->i_sb->s_root->d_inode)->uii_inode);
KFREE(stopd(inode->i_sb)->usi_data);
/* Update the real pointers. */
dtohd_ptr(inode->i_sb->s_root) = new_udi_dentry;
itohi_ptr(inode->i_sb->s_root->d_inode) = new_uii_inode;
stopd(inode->i_sb)->usi_data = new_data;
/* Re-NULL the new ones so we don't try to free them. */
new_data = NULL;
new_udi_dentry = NULL;
new_uii_inode = NULL;
/* Put the new dentry information into it's slot. */
set_dtohd_index(inode->i_sb->s_root, addargs->ab_branch, nd.dentry);
set_itohi_index(inode->i_sb->s_root->d_inode, addargs->ab_branch,
IGRAB(nd.dentry->d_inode));
set_branchperms(inode->i_sb, addargs->ab_branch, addargs->ab_perms);
set_branch_count(inode->i_sb, addargs->ab_branch, 0);
set_stohiddenmnt_index(inode->i_sb, addargs->ab_branch, nd.mnt);
set_stohs_index(inode->i_sb, addargs->ab_branch, nd.dentry->d_sb);
atomic_set(&dtopd(inode->i_sb->s_root)->udi_generation, gen);
atomic_set(&itopd(inode->i_sb->s_root->d_inode)->uii_generation, gen);
fixputmaps(inode->i_sb);
out:
unlock_dentry(inode->i_sb->s_root);
unionfs_write_unlock(inode->i_sb);
KFREE(new_udi_dentry);
KFREE(new_uii_inode);
KFREE(new_data);
KFREE(addargs);
if (path)
putname(path);
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);
}
int ll_revalidate_it(struct dentry *de, int lookup_flags,
struct lookup_intent *it)
{
struct md_op_data *op_data;
struct ptlrpc_request *req = NULL;
struct lookup_intent lookup_it = { .it_op = IT_LOOKUP };
struct obd_export *exp;
struct inode *parent = de->d_parent->d_inode;
int rc, first = 0;
ENTRY;
CDEBUG(D_VFSTRACE, "VFS Op:name=%s,intent=%s\n", de->d_name.name,
LL_IT2STR(it));
if (de->d_inode == NULL) {
/* We can only use negative dentries if this is stat or lookup,
for opens and stuff we do need to query server. */
/* If there is IT_CREAT in intent op set, then we must throw
away this negative dentry and actually do the request to
kernel to create whatever needs to be created (if possible)*/
if (it && (it->it_op & IT_CREAT))
RETURN(0);
if (de->d_flags & DCACHE_LUSTRE_INVALID)
RETURN(0);
rc = ll_have_md_lock(parent, MDS_INODELOCK_UPDATE, LCK_MINMODE);
GOTO(out_sa, rc);
}
/* Never execute intents for mount points.
* Attributes will be fixed up in ll_inode_revalidate_it */
if (d_mountpoint(de))
GOTO(out_sa, rc = 1);
/* need to get attributes in case root got changed from other client */
if (de == de->d_sb->s_root) {
rc = __ll_inode_revalidate_it(de, it, MDS_INODELOCK_LOOKUP);
if (rc == 0)
rc = 1;
GOTO(out_sa, rc);
}
exp = ll_i2mdexp(de->d_inode);
OBD_FAIL_TIMEOUT(OBD_FAIL_MDC_REVALIDATE_PAUSE, 5);
ll_frob_intent(&it, &lookup_it);
LASSERT(it);
if (it->it_op == IT_LOOKUP && !(de->d_flags & DCACHE_LUSTRE_INVALID))
GOTO(out_sa, rc = 1);
op_data = ll_prep_md_op_data(NULL, parent, de->d_inode,
de->d_name.name, de->d_name.len,
0, LUSTRE_OPC_ANY, NULL);
if (IS_ERR(op_data))
RETURN(PTR_ERR(op_data));
if ((it->it_op == IT_OPEN) && de->d_inode) {
struct inode *inode = de->d_inode;
struct ll_inode_info *lli = ll_i2info(inode);
struct obd_client_handle **och_p;
__u64 *och_usecount;
/*
* We used to check for MDS_INODELOCK_OPEN here, but in fact
* just having LOOKUP lock is enough to justify inode is the
* same. And if inode is the same and we have suitable
* openhandle, then there is no point in doing another OPEN RPC
* just to throw away newly received openhandle. There are no
* security implications too, if file owner or access mode is
* change, LOOKUP lock is revoked.
*/
if (it->it_flags & FMODE_WRITE) {
och_p = &lli->lli_mds_write_och;
och_usecount = &lli->lli_open_fd_write_count;
} else if (it->it_flags & FMODE_EXEC) {
och_p = &lli->lli_mds_exec_och;
och_usecount = &lli->lli_open_fd_exec_count;
} else {
och_p = &lli->lli_mds_read_och;
och_usecount = &lli->lli_open_fd_read_count;
}
/* Check for the proper lock. */
if (!ll_have_md_lock(inode, MDS_INODELOCK_LOOKUP, LCK_MINMODE))
goto do_lock;
cfs_down(&lli->lli_och_sem);
if (*och_p) { /* Everything is open already, do nothing */
/*(*och_usecount)++; Do not let them steal our open
handle from under us */
/* XXX The code above was my original idea, but in case
we have the handle, but we cannot use it due to later
checks (e.g. O_CREAT|O_EXCL flags set), nobody
would decrement counter increased here. So we just
hope the lock won't be invalidated in between. But
if it would be, we'll reopen the open request to
MDS later during file open path */
cfs_up(&lli->lli_och_sem);
ll_finish_md_op_data(op_data);
RETURN(1);
} else {
cfs_up(&lli->lli_och_sem);
}
}
if (it->it_op == IT_GETATTR) {
first = ll_statahead_enter(parent, &de, 0);
if (first == 1) {
ll_statahead_exit(parent, de, 1);
ll_finish_md_op_data(op_data);
GOTO(out, rc = 1);
}
}
do_lock:
it->it_create_mode &= ~current->fs->umask;
it->it_create_mode |= M_CHECK_STALE;
rc = md_intent_lock(exp, op_data, NULL, 0, it,
lookup_flags,
&req, ll_md_blocking_ast, 0);
it->it_create_mode &= ~M_CHECK_STALE;
ll_finish_md_op_data(op_data);
if (it->it_op == IT_GETATTR && !first)
/* If there are too many locks on client-side, then some
* locks taken by statahead maybe dropped automatically
* before the real "revalidate" using them. */
ll_statahead_exit(parent, de, req == NULL ? rc : 0);
else if (first == -EEXIST)
ll_statahead_mark(parent, de);
/* If req is NULL, then md_intent_lock only tried to do a lock match;
* if all was well, it will return 1 if it found locks, 0 otherwise. */
if (req == NULL && rc >= 0) {
if (!rc)
goto do_lookup;
GOTO(out, rc);
}
if (rc < 0) {
if (rc != -ESTALE) {
CDEBUG(D_INFO, "ll_intent_lock: rc %d : it->it_status "
"%d\n", rc, it->d.lustre.it_status);
}
GOTO(out, rc = 0);
}
revalidate_finish:
rc = ll_revalidate_it_finish(req, it, de);
if (rc != 0) {
if (rc != -ESTALE && rc != -ENOENT)
ll_intent_release(it);
GOTO(out, rc = 0);
}
if ((it->it_op & IT_OPEN) && de->d_inode &&
!S_ISREG(de->d_inode->i_mode) &&
!S_ISDIR(de->d_inode->i_mode)) {
ll_release_openhandle(de, it);
}
rc = 1;
/* unfortunately ll_intent_lock may cause a callback and revoke our
* dentry */
cfs_spin_lock(&ll_lookup_lock);
spin_lock(&dcache_lock);
lock_dentry(de);
__d_drop(de);
unlock_dentry(de);
d_rehash_cond(de, 0);
spin_unlock(&dcache_lock);
cfs_spin_unlock(&ll_lookup_lock);
out:
/* We do not free request as it may be reused during following lookup
* (see comment in mdc/mdc_locks.c::mdc_intent_lock()), request will
* be freed in ll_lookup_it or in ll_intent_release. But if
* request was not completed, we need to free it. (bug 5154, 9903) */
if (req != NULL && !it_disposition(it, DISP_ENQ_COMPLETE))
ptlrpc_req_finished(req);
if (rc == 0) {
ll_unhash_aliases(de->d_inode);
/* done in ll_unhash_aliases()
dentry->d_flags |= DCACHE_LUSTRE_INVALID; */
} else {
CDEBUG(D_DENTRY, "revalidated dentry %.*s (%p) parent %p "
"inode %p refc %d\n", de->d_name.len,
de->d_name.name, de, de->d_parent, de->d_inode,
atomic_read(&de->d_count));
if (first != 1) {
if (de->d_flags & DCACHE_LUSTRE_INVALID) {
lock_dentry(de);
de->d_flags &= ~DCACHE_LUSTRE_INVALID;
unlock_dentry(de);
}
ll_lookup_finish_locks(it, de);
}
}
RETURN(rc);
/*
* This part is here to combat evil-evil race in real_lookup on 2.6
* kernels. The race details are: We enter do_lookup() looking for some
* name, there is nothing in dcache for this name yet and d_lookup()
* returns NULL. We proceed to real_lookup(), and while we do this,
* another process does open on the same file we looking up (most simple
* reproducer), open succeeds and the dentry is added. Now back to
* us. In real_lookup() we do d_lookup() again and suddenly find the
* dentry, so we call d_revalidate on it, but there is no lock, so
* without this code we would return 0, but unpatched real_lookup just
* returns -ENOENT in such a case instead of retrying the lookup. Once
* this is dealt with in real_lookup(), all of this ugly mess can go and
* we can just check locks in ->d_revalidate without doing any RPCs
* ever.
*/
do_lookup:
if (it != &lookup_it) {
/* MDS_INODELOCK_UPDATE needed for IT_GETATTR case. */
if (it->it_op == IT_GETATTR)
lookup_it.it_op = IT_GETATTR;
ll_lookup_finish_locks(it, de);
it = &lookup_it;
}
/* Do real lookup here. */
op_data = ll_prep_md_op_data(NULL, parent, NULL, de->d_name.name,
de->d_name.len, 0, (it->it_op & IT_CREAT ?
LUSTRE_OPC_CREATE :
LUSTRE_OPC_ANY), NULL);
if (IS_ERR(op_data))
RETURN(PTR_ERR(op_data));
rc = md_intent_lock(exp, op_data, NULL, 0, it, 0, &req,
ll_md_blocking_ast, 0);
if (rc >= 0) {
struct mdt_body *mdt_body;
struct lu_fid fid = {.f_seq = 0, .f_oid = 0, .f_ver = 0};
mdt_body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
if (de->d_inode)
fid = *ll_inode2fid(de->d_inode);
/* see if we got same inode, if not - return error */
if (lu_fid_eq(&fid, &mdt_body->fid1)) {
ll_finish_md_op_data(op_data);
op_data = NULL;
goto revalidate_finish;
}
ll_intent_release(it);
}
ll_finish_md_op_data(op_data);
GOTO(out, rc = 0);
out_sa:
/*
* For rc == 1 case, should not return directly to prevent losing
* statahead windows; for rc == 0 case, the "lookup" will be done later.
*/
if (it && it->it_op == IT_GETATTR && rc == 1) {
first = ll_statahead_enter(parent, &de, 0);
if (first >= 0)
ll_statahead_exit(parent, de, 1);
else if (first == -EEXIST)
ll_statahead_mark(parent, de);
}
return rc;
}
#if 0
static void ll_pin(struct dentry *de, struct vfsmount *mnt, int flag)
{
struct inode *inode= de->d_inode;
struct ll_sb_info *sbi = ll_i2sbi(inode);
struct ll_dentry_data *ldd = ll_d2d(de);
struct obd_client_handle *handle;
struct obd_capa *oc;
int rc = 0;
ENTRY;
LASSERT(ldd);
cfs_lock_kernel();
/* Strictly speaking this introduces an additional race: the
* increments should wait until the rpc has returned.
* However, given that at present the function is void, this
* issue is moot. */
if (flag == 1 && (++ldd->lld_mnt_count) > 1) {
cfs_unlock_kernel();
EXIT;
return;
}
if (flag == 0 && (++ldd->lld_cwd_count) > 1) {
cfs_unlock_kernel();
EXIT;
return;
}
cfs_unlock_kernel();
handle = (flag) ? &ldd->lld_mnt_och : &ldd->lld_cwd_och;
oc = ll_mdscapa_get(inode);
rc = obd_pin(sbi->ll_md_exp, ll_inode2fid(inode), oc, handle, flag);
capa_put(oc);
if (rc) {
cfs_lock_kernel();
memset(handle, 0, sizeof(*handle));
if (flag == 0)
ldd->lld_cwd_count--;
else
ldd->lld_mnt_count--;
cfs_unlock_kernel();
}
EXIT;
return;
}
static void ll_unpin(struct dentry *de, struct vfsmount *mnt, int flag)
{
struct ll_sb_info *sbi = ll_i2sbi(de->d_inode);
struct ll_dentry_data *ldd = ll_d2d(de);
struct obd_client_handle handle;
int count, rc = 0;
ENTRY;
LASSERT(ldd);
cfs_lock_kernel();
/* Strictly speaking this introduces an additional race: the
* increments should wait until the rpc has returned.
* However, given that at present the function is void, this
* issue is moot. */
handle = (flag) ? ldd->lld_mnt_och : ldd->lld_cwd_och;
if (handle.och_magic != OBD_CLIENT_HANDLE_MAGIC) {
/* the "pin" failed */
cfs_unlock_kernel();
EXIT;
return;
}
if (flag)
count = --ldd->lld_mnt_count;
else
count = --ldd->lld_cwd_count;
cfs_unlock_kernel();
if (count != 0) {
EXIT;
return;
}
rc = obd_unpin(sbi->ll_md_exp, &handle, flag);
EXIT;
return;
}
#endif
#ifdef HAVE_VFS_INTENT_PATCHES
int ll_revalidate_nd(struct dentry *dentry, struct nameidata *nd)
{
int rc;
ENTRY;
if (nd && nd->flags & LOOKUP_LAST && !(nd->flags & LOOKUP_LINK_NOTLAST))
rc = ll_revalidate_it(dentry, nd->flags, &nd->intent);
else
rc = ll_revalidate_it(dentry, 0, NULL);
RETURN(rc);
}
static int unionfs_symlink(struct inode *dir, struct dentry *dentry,
const char *symname)
{
int err = 0;
struct dentry *hidden_dentry = NULL;
struct dentry *whiteout_dentry = NULL;
struct dentry *hidden_dir_dentry = NULL;
umode_t mode;
int bindex = 0, bstart;
char *name = NULL;
print_entry_location();
lock_dentry(dentry);
fist_print_dentry("IN unionfs_symlink", dentry);
/* We start out in the leftmost branch. */
bstart = dbstart(dentry);
hidden_dentry = dtohd(dentry);
/* check if whiteout exists in this branch, i.e. lookup .wh.foo first. If present, delete it */
name = alloc_whname(dentry->d_name.name, dentry->d_name.len);
if (IS_ERR(name)) {
err = PTR_ERR(name);
goto out;
}
whiteout_dentry =
LOOKUP_ONE_LEN(name, hidden_dentry->d_parent,
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_symlink() */
hidden_dir_dentry = lock_parent(whiteout_dentry);
fist_print_generic_dentry("HDD", hidden_dir_dentry);
fist_print_generic_dentry("WD", whiteout_dentry);
if (!(err = is_robranch_super(dentry->d_sb, bstart))) {
err =
vfs_unlink(hidden_dir_dentry->d_inode,
whiteout_dentry);
}
DPUT(whiteout_dentry);
fist_copy_attr_times(dir, hidden_dir_dentry->d_inode);
/* propagate number of hard-links */
dir->i_nlink = get_nlinks(dir);
unlock_dir(hidden_dir_dentry);
if (err) {
/* exit if the error returned was NOT -EROFS */
if (!IS_COPYUP_ERR(err))
goto out;
/* should now try to create symlink in the another branch */
bstart--;
}
}
/* deleted whiteout if it was present, now do a normal vfs_symlink() with
possible recursive directory creation */
for (bindex = bstart; bindex >= 0; bindex--) {
hidden_dentry = dtohd_index(dentry, bindex);
if (!hidden_dentry) {
/* if hidden_dentry is NULL, create the entire
* dentry directory structure in branch 'bindex'. hidden_dentry will NOT be null when
* bindex == bstart because lookup passed as a negative unionfs dentry pointing to a
* lone negative underlying dentry */
hidden_dentry = create_parents(dir, dentry, bindex);
if (!hidden_dentry || IS_ERR(hidden_dentry)) {
if (IS_ERR(hidden_dentry)) {
err = PTR_ERR(hidden_dentry);
}
fist_dprint(8,
"hidden dentry NULL (or error) for bindex = %d\n",
bindex);
continue;
}
}
hidden_dir_dentry = lock_parent(hidden_dentry);
if (!(err = is_robranch_super(dentry->d_sb, bindex))) {
mode = S_IALLUGO;
err =
vfs_symlink(hidden_dir_dentry->d_inode,
hidden_dentry, symname, mode);
}
unlock_dir(hidden_dir_dentry);
if (err || !hidden_dentry->d_inode) {
/* break out of for loop if error returned was NOT -EROFS */
if (!IS_COPYUP_ERR(err))
break;
} else {
err = unionfs_interpose(dentry, dir->i_sb, 0);
if (!err) {
fist_copy_attr_timesizes(dir,
hidden_dir_dentry->
d_inode);
/* update number of links on parent directory */
dir->i_nlink = get_nlinks(dir);
}
break;
}
}
out:
if (!dentry->d_inode)
d_drop(dentry);
KFREE(name);
fist_print_dentry("OUT unionfs_symlink :", dentry);
unlock_dentry(dentry);
print_exit_status(err);
return err;
}
