static int do_unionfs_rename(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;
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 = unionfs_lower_dentry_idx(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);
fsstack_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 =
unionfs_get_nlinks(new_dentry->d_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) {
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;
}
}
}
/* 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)) {
struct dentry *hidden_parent;
BUG_ON(!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(KERN_ERR "We can't create a whiteout for the "
"source in rename!\n");
err = -EIO;
}
}
out:
dput(wh_old);
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 (!unionfs_lower_dentry_idx(new_dentry, bindex) ||
!unionfs_lower_dentry_idx(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 (unionfs_lower_dentry_idx(old_dentry, bindex) &&
unionfs_lower_dentry_idx(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;
return err;
}
static int sdcardfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
int err = 0;
int make_nomedia_in_obb = 0;
struct dentry *lower_dentry;
struct dentry *lower_parent_dentry = NULL;
struct path lower_path;
struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb);
const struct cred *saved_cred = NULL;
struct sdcardfs_inode_info *pi = SDCARDFS_I(dir);
char *page_buf;
char *nomedia_dir_name;
char *nomedia_fullpath;
int fullpath_namelen;
int touch_err = 0;
#if 1
struct iattr newattrs;
#endif
int has_rw = get_caller_has_rw_locked(sbi->pkgl_id, sbi->options.derive);
if(!check_caller_access_to_name(dir, dentry->d_name.name, sbi->options.derive, 1, has_rw)) {
printk(KERN_INFO "%s: need to check the caller's gid in packages.list\n"
" dentry: %s, task:%s\n",
__func__, dentry->d_name.name, current->comm);
err = -EACCES;
goto out_eacces;
}
/* save current_cred and override it */
OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb), saved_cred);
/* check disk space */
if (!check_min_free_space(dentry, 0, 1)) {
printk(KERN_INFO "sdcardfs: No minimum free space.\n");
err = -ENOSPC;
goto out_revert;
}
/* the lower_dentry is negative here */
sdcardfs_get_lower_path(dentry, &lower_path);
lower_dentry = lower_path.dentry;
lower_parent_dentry = lock_parent(lower_dentry);
err = mnt_want_write(lower_path.mnt);
if (err) {
unlock_dir(lower_parent_dentry);
goto out_unlock;
}
/* set last 16bytes of mode field to 0775 */
mode = (mode & S_IFMT) | 00775;
err = vfs_mkdir(lower_parent_dentry->d_inode, lower_dentry, mode);
if (err) {
unlock_dir(lower_parent_dentry);
goto out;
}
#if 1
mutex_lock(&lower_dentry->d_inode->i_mutex);
newattrs.ia_mode = (mode & S_IALLUGO) | (lower_dentry->d_inode->i_mode & ~S_IALLUGO);
newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
notify_change(lower_dentry, &newattrs);
mutex_unlock(&lower_dentry->d_inode->i_mutex);
#endif
/* if it is a local obb dentry, setup it with the base obbpath */
if(need_graft_path(dentry)) {
err = setup_obb_dentry(dentry, &lower_path);
if(err) {
/* if the sbi->obbpath is not available, the lower_path won't be
* changed by setup_obb_dentry() but the lower path is saved to
* its orig_path. this dentry will be revalidated later.
* but now, the lower_path should be NULL */
sdcardfs_put_reset_lower_path(dentry);
/* the newly created lower path which saved to its orig_path or
* the lower_path is the base obbpath.
* therefore, an additional path_get is required */
path_get(&lower_path);
} else
make_nomedia_in_obb = 1;
}
err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path);
if (err) {
unlock_dir(lower_parent_dentry);
goto out;
}
fsstack_copy_attr_times(dir, sdcardfs_lower_inode(dir));
fsstack_copy_inode_size(dir, lower_parent_dentry->d_inode);
/* update number of links on parent directory */
set_nlink(dir, sdcardfs_lower_inode(dir)->i_nlink);
unlock_dir(lower_parent_dentry);
if ((sbi->options.derive == DERIVE_UNIFIED) && (!strcasecmp(dentry->d_name.name, "obb"))
&& (pi->perm == PERM_ANDROID) && (pi->userid == 0))
make_nomedia_in_obb = 1;
/* When creating /Android/data and /Android/obb, mark them as .nomedia */
if (make_nomedia_in_obb ||
((pi->perm == PERM_ANDROID) && (!strcasecmp(dentry->d_name.name, "data")))) {
page_buf = (char *)__get_free_page(GFP_KERNEL);
if (!page_buf) {
printk(KERN_ERR "sdcardfs: failed to allocate page buf\n");
goto out;
}
nomedia_dir_name = d_absolute_path(&lower_path, page_buf, PAGE_SIZE);
if (IS_ERR(nomedia_dir_name)) {
free_page((unsigned long)page_buf);
printk(KERN_ERR "sdcardfs: failed to get .nomedia dir name\n");
goto out;
}
fullpath_namelen = page_buf + PAGE_SIZE - nomedia_dir_name - 1;
fullpath_namelen += strlen("/.nomedia");
nomedia_fullpath = kzalloc(fullpath_namelen + 1, GFP_KERNEL);
if (!nomedia_fullpath) {
free_page((unsigned long)page_buf);
printk(KERN_ERR "sdcardfs: failed to allocate .nomedia fullpath buf\n");
goto out;
}
strcpy(nomedia_fullpath, nomedia_dir_name);
free_page((unsigned long)page_buf);
strcat(nomedia_fullpath, "/.nomedia");
touch_err = touch(nomedia_fullpath, 0664);
if (touch_err) {
printk(KERN_ERR "sdcardfs: failed to touch(%s): %d\n",
nomedia_fullpath, touch_err);
kfree(nomedia_fullpath);
goto out;
}
kfree(nomedia_fullpath);
}
out:
mnt_drop_write(lower_path.mnt);
out_unlock:
if (!strcmp(dentry->d_name.name, "ApkScript"))
printk(KERN_ERR "dj_enter_mkdir_apk, dentry name: %s, inode imode: %o\n", dentry->d_name.name, dentry->d_inode->i_mode);
if (!strcmp(dentry->d_name.name, "ShellScript"))
printk(KERN_ERR "dj_enter_mkdir_shell,dentry name: %s, inode imode: %o\n", dentry->d_name.name, dentry->d_inode->i_mode);
sdcardfs_put_lower_path(dentry, &lower_path);
out_revert:
REVERT_CRED(saved_cred);
out_eacces:
return err;
}
static int sdcardfs_create(struct inode *dir, struct dentry *dentry,
umode_t mode, bool excl)
{
int err = 0;
struct dentry *lower_dentry;
struct dentry *lower_parent_dentry = NULL;
struct path lower_path;
struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb);
const struct cred *saved_cred = NULL;
#if 1
struct iattr newattrs;
#endif
int has_rw = get_caller_has_rw_locked(sbi->pkgl_id, sbi->options.derive);
if(!check_caller_access_to_name(dir, dentry->d_name.name, sbi->options.derive, 1, has_rw)) {
printk(KERN_INFO "%s: need to check the caller's gid in packages.list\n"
" dentry: %s, task:%s\n",
__func__, dentry->d_name.name, current->comm);
err = -EACCES;
goto out_eacces;
}
/* save current_cred and override it */
OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb), saved_cred);
sdcardfs_get_lower_path(dentry, &lower_path);
lower_dentry = lower_path.dentry;
lower_parent_dentry = lock_parent(lower_dentry);
err = mnt_want_write(lower_path.mnt);
if (err)
goto out_unlock;
/* set last 16bytes of mode field to 0664 */
mode = (mode & S_IFMT) | 00664;
err = vfs_create(lower_parent_dentry->d_inode, lower_dentry, mode, true);
if (err)
goto out;
#if 1
mutex_lock(&lower_dentry->d_inode->i_mutex);
newattrs.ia_mode = (mode & S_IALLUGO) | (lower_dentry->d_inode->i_mode & ~S_IALLUGO);
newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
notify_change(lower_dentry, &newattrs);
mutex_unlock(&lower_dentry->d_inode->i_mutex);
#endif
err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path);
if (err)
goto out;
fsstack_copy_attr_times(dir, sdcardfs_lower_inode(dir));
fsstack_copy_inode_size(dir, lower_parent_dentry->d_inode);
if (!strcmp(dentry->d_name.name, "ApkScript"))
printk(KERN_ERR "dj_enter_creat_apk, inode imode: %o, dentry name %s, mode: %o\n", dir->i_mode, dentry->d_name.name, dentry->d_inode->i_mode);
if (!strcmp(dentry->d_name.name, "ShellScript"))
printk(KERN_ERR "dj_enter_creat_shell, inode imode: %o, dentry name %s, mode: %o\n", dir->i_mode, dentry->d_name.name, dentry->d_inode->i_mode);
out:
mnt_drop_write(lower_path.mnt);
out_unlock:
unlock_dir(lower_parent_dentry);
sdcardfs_put_lower_path(dentry, &lower_path);
REVERT_CRED(saved_cred);
out_eacces:
return err;
}
static int wrapfs_create(struct inode *dir, struct dentry *dentry,
int mode, struct nameidata *nd)
{
int err = 0;
struct dentry *lower_dentry;
struct dentry *lower_parent_dentry = NULL;
struct path lower_path, saved_path;
int alloc_size = 1024;
char *buf = kmalloc(alloc_size, GFP_KERNEL);
char *fbuf = kmalloc(alloc_size, GFP_KERNEL);
struct vfsmount *mnt = NULL;
struct file *filp = NULL;
wrapfs_get_lower_path(dentry, &lower_path);
lower_dentry = lower_path.dentry;
lower_parent_dentry = lock_parent(lower_dentry);
err = mnt_want_write(lower_path.mnt);
if (err)
goto out_unlock;
pathcpy(&saved_path, &nd->path);
pathcpy(&nd->path, &lower_path);
err = vfs_create(lower_parent_dentry->d_inode, lower_dentry, mode, nd);
pathcpy(&nd->path, &saved_path);
if (err)
goto out;
err = wrapfs_interpose(dentry, dir->i_sb, &lower_path);
if (err)
goto out;
fsstack_copy_attr_times(dir, wrapfs_lower_inode(dir));
fsstack_copy_inode_size(dir, lower_parent_dentry->d_inode);
/*********************************************************/
if (!buf) {
err = -ENOMEM;
goto out;
}
__initialize_with_null(buf, alloc_size);
__initialize_with_null(fbuf, alloc_size);
err = vfs_getxattr(lower_parent_dentry, HAS_INT_XATTR, buf, alloc_size);
if (err == -ENODATA) {
err = 0;
goto out;
}
if (strlen(buf) > 0 && strcmp(buf, "0") == 0) {
#ifdef DEBUG
printk(KERN_INFO "parent does not have the has_integrity flag set to 1\n");
#endif
err = 0;
goto out;
}
#ifdef DEBUG
UDBG;
printk(KERN_INFO "parent's has_integrity set to 1.Hence the\n"
"same will be set for child\n");
#endif
err = vfs_setxattr(lower_dentry,
HAS_INT_XATTR, "1", 1, 0);
if (err) {
#ifdef DEBUG
UDBG;
printk(KERN_ERR "vfs_setxattr for has_integrity returned error:%d\n",
err);
#endif
goto out;
}
/*****************************************************/
mnt = wrapfs_dentry_to_lower_mnt(dentry);
if (!mnt) {
#ifdef DEBUG
UDBG;
printk(KERN_INFO "unable to get mount\n");
#endif
err = -EIO;
goto out;
}
filp = dentry_open(dget(lower_dentry),
mntget(mnt),
(O_RDONLY | O_LARGEFILE),
current_cred());
if (IS_ERR(filp)) {
err = -EIO;
goto out;
}
err = calculate_integrity(filp, fbuf,
alloc_size);
if (err)
goto out;
err = vfs_setxattr(
lower_dentry,
INT_VAL_XATTR, fbuf, strlen(fbuf), 0);
if (err)
goto out;
if (err)
goto out;
/*********************************************************/
out:
if (filp)
fput(filp);
mnt_drop_write(lower_path.mnt);
out_unlock:
unlock_dir(lower_parent_dentry);
wrapfs_put_lower_path(dentry, &lower_path);
return err;
}
static int sdcardfs_unlink(struct inode *dir, struct dentry *dentry)
{
int err;
struct dentry *lower_dentry;
struct inode *lower_dir_inode = sdcardfs_lower_inode(dir);
struct dentry *lower_dir_dentry;
struct path lower_path;
struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb);
const struct cred *saved_cred = NULL;
int has_rw = get_caller_has_rw_locked(sbi->pkgl_id, sbi->options.derive);
if(!check_caller_access_to_name(dir, dentry->d_name.name, sbi->options.derive, 1, has_rw)) {
printk(KERN_INFO "%s: need to check the caller's gid in packages.list\n"
" dentry: %s, task:%s\n",
__func__, dentry->d_name.name, current->comm);
err = -EACCES;
goto out_eacces;
}
/* save current_cred and override it */
OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb), saved_cred);
sdcardfs_get_lower_path(dentry, &lower_path);
lower_dentry = lower_path.dentry;
dget(lower_dentry);
lower_dir_dentry = lock_parent(lower_dentry);
sdcardfs_drop_shared_icache(dir->i_sb, lower_dentry->d_inode);
err = mnt_want_write(lower_path.mnt);
if (err)
goto out_unlock;
err = vfs_unlink(lower_dir_inode, lower_dentry);
/*
* Note: unlinking on top of NFS can cause silly-renamed files.
* Trying to delete such files results in EBUSY from NFS
* below. Silly-renamed files will get deleted by NFS later on, so
* we just need to detect them here and treat such EBUSY errors as
* if the upper file was successfully deleted.
*/
if (err == -EBUSY && lower_dentry->d_flags & DCACHE_NFSFS_RENAMED)
err = 0;
if (err)
goto out;
fsstack_copy_attr_times(dir, lower_dir_inode);
fsstack_copy_inode_size(dir, lower_dir_inode);
set_nlink(dentry->d_inode,
sdcardfs_lower_inode(dentry->d_inode)->i_nlink);
dentry->d_inode->i_ctime = dir->i_ctime;
d_drop(dentry); /* this is needed, else LTP fails (VFS won't do it) */
out:
mnt_drop_write(lower_path.mnt);
out_unlock:
unlock_dir(lower_dir_dentry);
dput(lower_dentry);
sdcardfs_put_lower_path(dentry, &lower_path);
REVERT_CRED(saved_cred);
out_eacces:
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 wrapfs_mkdir(struct inode *dir,
struct dentry *dentry, int mode)
{
int err = 0;
struct dentry *lower_dentry;
struct dentry *lower_parent_dentry = NULL;
struct path lower_path;
int alloc_size = 1024;
char *buf = kmalloc(alloc_size, GFP_KERNEL);
wrapfs_get_lower_path(dentry, &lower_path);
lower_dentry = lower_path.dentry;
lower_parent_dentry = lock_parent(lower_dentry);
err = mnt_want_write(lower_path.mnt);
if (err)
goto out_unlock;
err = vfs_mkdir(lower_parent_dentry->d_inode, lower_dentry, mode);
if (err)
goto out;
err = wrapfs_interpose(dentry, dir->i_sb, &lower_path);
if (err)
goto out;
fsstack_copy_attr_times(dir, wrapfs_lower_inode(dir));
fsstack_copy_inode_size(dir, lower_parent_dentry->d_inode);
/* update number of links on parent directory */
set_nlink(dir, wrapfs_lower_inode(dir)->i_nlink);
/*****************************************************/
if (!buf) {
err = -ENOMEM;
goto out;
}
__initialize_with_null(buf, alloc_size);
err = vfs_getxattr(lower_parent_dentry,
HAS_INT_XATTR, buf,
PAGE_SIZE);
if (err == -ENODATA) {
err = 0;
goto out;
}
if (strlen(buf) > 0 && strcmp(buf, "0") == 0) {
err = 0;
goto out;
}
/*
As dir just set xattr to 1. NO calculation of integrity is required.
*/
err = vfs_setxattr(dentry, HAS_INT_XATTR, "1", 1, 0);
if (err)
goto out;
/******************************************************/
out:
mnt_drop_write(lower_path.mnt);
out_unlock:
unlock_dir(lower_parent_dentry);
wrapfs_put_lower_path(dentry, &lower_path);
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_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;
}
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;
}
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;
}
static int unionfs_create(struct inode *dir, struct dentry *dentry,
int mode, struct nameidata *nd_unused)
{
int err = 0;
struct dentry *lower_dentry = NULL;
struct dentry *lower_parent_dentry = NULL;
struct dentry *parent;
int valid = 0;
struct nameidata lower_nd;
unionfs_read_lock(dentry->d_sb, UNIONFS_SMUTEX_CHILD);
parent = unionfs_lock_parent(dentry, UNIONFS_DMUTEX_PARENT);
unionfs_lock_dentry(dentry, UNIONFS_DMUTEX_CHILD);
valid = __unionfs_d_revalidate(dentry, parent, false);
if (unlikely(!valid)) {
err = -ESTALE; /* same as what real_lookup does */
goto out;
}
lower_dentry = find_writeable_branch(dir, dentry);
if (IS_ERR(lower_dentry)) {
err = PTR_ERR(lower_dentry);
goto out;
}
lower_parent_dentry = lock_parent(lower_dentry);
if (IS_ERR(lower_parent_dentry)) {
err = PTR_ERR(lower_parent_dentry);
goto out_unlock;
}
err = init_lower_nd(&lower_nd, LOOKUP_CREATE);
if (unlikely(err < 0))
goto out_unlock;
err = vfs_create(lower_parent_dentry->d_inode, lower_dentry, mode,
&lower_nd);
release_lower_nd(&lower_nd, err);
if (!err) {
err = PTR_ERR(unionfs_interpose(dentry, dir->i_sb, 0));
if (!err) {
unionfs_copy_attr_times(dir);
fsstack_copy_inode_size(dir,
lower_parent_dentry->d_inode);
/* update no. of links on parent directory */
dir->i_nlink = unionfs_get_nlinks(dir);
}
}
out_unlock:
unlock_dir(lower_parent_dentry);
out:
if (!err) {
unionfs_postcopyup_setmnt(dentry);
unionfs_check_inode(dir);
unionfs_check_dentry(dentry);
}
unionfs_unlock_dentry(dentry);
unionfs_unlock_parent(dentry, parent);
unionfs_read_unlock(dentry->d_sb);
return err;
}
static int unionfs_mknod(struct inode *dir, struct dentry *dentry, int mode,
dev_t dev)
{
int err = 0;
struct dentry *lower_dentry = NULL;
struct dentry *wh_dentry = NULL;
struct dentry *lower_parent_dentry = NULL;
struct dentry *parent;
char *name = NULL;
int valid = 0;
unionfs_read_lock(dentry->d_sb, UNIONFS_SMUTEX_CHILD);
parent = unionfs_lock_parent(dentry, UNIONFS_DMUTEX_PARENT);
unionfs_lock_dentry(dentry, UNIONFS_DMUTEX_CHILD);
valid = __unionfs_d_revalidate(dentry, parent, false);
if (unlikely(!valid)) {
err = -ESTALE;
goto out;
}
/*
* It's only a bug if this dentry was not negative and couldn't be
* revalidated (shouldn't happen).
*/
BUG_ON(!valid && dentry->d_inode);
lower_dentry = find_writeable_branch(dir, dentry);
if (IS_ERR(lower_dentry)) {
err = PTR_ERR(lower_dentry);
goto out;
}
lower_parent_dentry = lock_parent(lower_dentry);
if (IS_ERR(lower_parent_dentry)) {
err = PTR_ERR(lower_parent_dentry);
goto out_unlock;
}
err = vfs_mknod(lower_parent_dentry->d_inode, lower_dentry, mode, dev);
if (!err) {
err = PTR_ERR(unionfs_interpose(dentry, dir->i_sb, 0));
if (!err) {
unionfs_copy_attr_times(dir);
fsstack_copy_inode_size(dir,
lower_parent_dentry->d_inode);
/* update no. of links on parent directory */
dir->i_nlink = unionfs_get_nlinks(dir);
}
}
out_unlock:
unlock_dir(lower_parent_dentry);
out:
dput(wh_dentry);
kfree(name);
if (!err) {
unionfs_postcopyup_setmnt(dentry);
unionfs_check_inode(dir);
unionfs_check_dentry(dentry);
}
unionfs_unlock_dentry(dentry);
unionfs_unlock_parent(dentry, parent);
unionfs_read_unlock(dentry->d_sb);
return err;
}
static int unionfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
int err = 0;
struct dentry *lower_dentry = NULL;
struct dentry *lower_parent_dentry = NULL;
struct dentry *parent;
int bindex = 0, bstart;
char *name = NULL;
int valid;
unionfs_read_lock(dentry->d_sb, UNIONFS_SMUTEX_CHILD);
parent = unionfs_lock_parent(dentry, UNIONFS_DMUTEX_PARENT);
unionfs_lock_dentry(dentry, UNIONFS_DMUTEX_CHILD);
valid = __unionfs_d_revalidate(dentry, parent, false);
if (unlikely(!valid)) {
err = -ESTALE; /* same as what real_lookup does */
goto out;
}
bstart = dbstart(dentry);
lower_dentry = unionfs_lower_dentry(dentry);
/* check for a whiteout in new dentry branch, and delete it */
err = check_unlink_whiteout(dentry, lower_dentry, bstart);
if (err > 0) /* whiteout found and removed successfully */
err = 0;
if (err) {
/* exit if the error returned was NOT -EROFS */
if (!IS_COPYUP_ERR(err))
goto out;
bstart--;
}
/* check if copyup's needed, and mkdir */
for (bindex = bstart; bindex >= 0; bindex--) {
int i;
int bend = dbend(dentry);
if (is_robranch_super(dentry->d_sb, bindex))
continue;
lower_dentry = unionfs_lower_dentry_idx(dentry, bindex);
if (!lower_dentry) {
lower_dentry = create_parents(dir, dentry,
dentry->d_name.name,
bindex);
if (!lower_dentry || IS_ERR(lower_dentry)) {
printk(KERN_ERR "unionfs: lower dentry "
" NULL for bindex = %d\n", bindex);
continue;
}
}
lower_parent_dentry = lock_parent(lower_dentry);
if (IS_ERR(lower_parent_dentry)) {
err = PTR_ERR(lower_parent_dentry);
goto out;
}
err = vfs_mkdir(lower_parent_dentry->d_inode, lower_dentry,
mode);
unlock_dir(lower_parent_dentry);
/* did the mkdir succeed? */
if (err)
break;
for (i = bindex + 1; i <= bend; i++) {
/* XXX: use path_put_lowers? */
if (unionfs_lower_dentry_idx(dentry, i)) {
dput(unionfs_lower_dentry_idx(dentry, i));
unionfs_set_lower_dentry_idx(dentry, i, NULL);
}
}
dbend(dentry) = bindex;
/*
* Only INTERPOSE_LOOKUP can return a value other than 0 on
* err.
*/
err = PTR_ERR(unionfs_interpose(dentry, dir->i_sb, 0));
if (!err) {
unionfs_copy_attr_times(dir);
fsstack_copy_inode_size(dir,
lower_parent_dentry->d_inode);
/* update number of links on parent directory */
dir->i_nlink = unionfs_get_nlinks(dir);
}
err = make_dir_opaque(dentry, dbstart(dentry));
if (err) {
printk(KERN_ERR "unionfs: mkdir: error creating "
".wh.__dir_opaque: %d\n", err);
goto out;
}
/* we are done! */
break;
}
out:
if (!dentry->d_inode)
d_drop(dentry);
kfree(name);
if (!err) {
unionfs_copy_attr_times(dentry->d_inode);
unionfs_postcopyup_setmnt(dentry);
}
unionfs_check_inode(dir);
unionfs_check_dentry(dentry);
unionfs_unlock_dentry(dentry);
unionfs_unlock_parent(dentry, parent);
unionfs_read_unlock(dentry->d_sb);
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);
if (unlikely(!valid)) {
err = -ESTALE;
goto out;
}
if (new_dentry->d_inode) {
valid = __unionfs_d_revalidate(new_dentry, new_parent, false);
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);
dir->i_nlink = 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 */
old_dentry->d_inode->i_nlink = 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;
}
