/*
* If we're not journaling and this is a just-created file, we have to
* sync our parent directory (if it was freshly created) since
* otherwise it will only be written by writeback, leaving a huge
* window during which a crash may lose the file. This may apply for
* the parent directory's parent as well, and so on recursively, if
* they are also freshly created.
*/
static int ext4_sync_parent(struct inode *inode)
{
struct dentry *dentry = NULL;
struct inode *next;
int ret = 0;
if (!ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY))
return 0;
inode = igrab(inode);
while (ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY)) {
ext4_clear_inode_state(inode, EXT4_STATE_NEWENTRY);
dentry = d_find_any_alias(inode);
if (!dentry)
break;
next = igrab(dentry->d_parent->d_inode);
dput(dentry);
if (!next)
break;
iput(inode);
inode = next;
ret = sync_mapping_buffers(inode->i_mapping);
if (ret)
break;
ret = sync_inode_metadata(inode, 1);
if (ret)
break;
}
iput(inode);
return ret;
}
/* drop all shared dentries from other superblocks */
void sdcardfs_drop_sb_icache(struct super_block *sb, unsigned long ino)
{
struct inode *inode = ilookup(sb, ino);
struct dentry *dentry, *dir_dentry;
if (!inode)
return;
dentry = d_find_any_alias(inode);
if (!dentry) {
iput(inode);
return;
}
dir_dentry = lock_parent(dentry);
mutex_lock(&inode->i_mutex);
set_nlink(inode, sdcardfs_lower_inode(inode)->i_nlink);
d_drop(dentry);
dont_mount(dentry);
mutex_unlock(&inode->i_mutex);
/* We don't d_delete() NFS sillyrenamed files--they still exist. */
if (!(dentry->d_flags & DCACHE_NFSFS_RENAMED)) {
fsnotify_link_count(inode);
d_delete(dentry);
}
unlock_dir(dir_dentry);
dput(dentry);
iput(inode);
}
/*
* If we're not journaling and this is a just-created file, we have to
* sync our parent directory (if it was freshly created) since
* otherwise it will only be written by writeback, leaving a huge
* window during which a crash may lose the file. This may apply for
* the parent directory's parent as well, and so on recursively, if
* they are also freshly created.
*/
static int ext4_sync_parent(struct inode *inode)
{
struct writeback_control wbc;
struct dentry *dentry = NULL;
struct inode *next;
int ret = 0;
if (!ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY))
return 0;
inode = igrab(inode);
while (ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY)) {
ext4_clear_inode_state(inode, EXT4_STATE_NEWENTRY);
dentry = d_find_any_alias(inode);
if (!dentry)
break;
next = igrab(dentry->d_parent->d_inode);
dput(dentry);
if (!next)
break;
iput(inode);
inode = next;
ret = sync_mapping_buffers(inode->i_mapping);
if (ret)
break;
memset(&wbc, 0, sizeof(wbc));
wbc.sync_mode = WB_SYNC_ALL;
wbc.nr_to_write = 0; /* only write out the inode */
ret = sync_inode(inode, &wbc);
if (ret)
break;
}
iput(inode);
return ret;
}
static int get_parent_ino(struct inode *inode, nid_t *pino)
{
struct dentry *dentry;
inode = igrab(inode);
dentry = d_find_any_alias(inode);
iput(inode);
if (!dentry)
return 0;
if (update_dent_inode(inode, inode, &dentry->d_name)) {
dput(dentry);
return 0;
}
*pino = parent_ino(dentry);
dput(dentry);
return 1;
}
int ovl_update_time(struct inode *inode, struct timespec *ts, int flags)
{
struct dentry *alias;
struct path upperpath;
if (!(flags & S_ATIME))
return 0;
alias = d_find_any_alias(inode);
if (!alias)
return 0;
ovl_path_upper(alias, &upperpath);
if (upperpath.dentry) {
touch_atime(&upperpath);
inode->i_atime = d_inode(upperpath.dentry)->i_atime;
}
dput(alias);
return 0;
}
void au_dir_ts(struct inode *dir, aufs_bindex_t bindex)
{
int perm, wkq_err;
aufs_bindex_t btop;
struct au_dir_ts_arg *arg;
struct dentry *dentry;
struct super_block *sb;
IMustLock(dir);
dentry = d_find_any_alias(dir);
AuDebugOn(!dentry);
sb = dentry->d_sb;
btop = au_ibtop(dir);
if (btop == bindex) {
au_cpup_attr_timesizes(dir);
goto out;
}
perm = au_sbr_perm(sb, btop);
if (!au_br_writable(perm))
goto out;
arg = kmalloc(sizeof(*arg), GFP_NOFS);
if (!arg)
goto out;
arg->dentry = dget(dentry); /* will be dput-ted by au_do_dir_ts() */
arg->brid = au_sbr_id(sb, bindex);
wkq_err = au_wkq_nowait(au_do_dir_ts, arg, sb, /*flags*/0);
if (unlikely(wkq_err)) {
pr_err("wkq %d\n", wkq_err);
dput(dentry);
kfree(arg);
}
out:
dput(dentry);
}
/*
* If we're not journaling and this is a just-created file, we have to
* sync our parent directory (if it was freshly created) since
* otherwise it will only be written by writeback, leaving a huge
* window during which a crash may lose the file. This may apply for
* the parent directory's parent as well, and so on recursively, if
* they are also freshly created.
*/
static int ext4_sync_parent(struct inode *inode)
{
struct dentry *dentry = NULL;
struct inode *next;
int ret = 0;
if (!ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY))
return 0;
inode = igrab(inode);
while (ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY)) {
ext4_clear_inode_state(inode, EXT4_STATE_NEWENTRY);
dentry = d_find_any_alias(inode);
if (!dentry)
break;
next = igrab(d_inode(dentry->d_parent));
dput(dentry);
if (!next)
break;
iput(inode);
inode = next;
/*
* The directory inode may have gone through rmdir by now. But
* the inode itself and its blocks are still allocated (we hold
* a reference to the inode so it didn't go through
* ext4_evict_inode()) and so we are safe to flush metadata
* blocks and the inode.
*/
ret = sync_mapping_buffers(inode->i_mapping);
if (ret)
break;
ret = sync_inode_metadata(inode, 1);
if (ret)
break;
}
iput(inode);
return ret;
}
int ovl_permission(struct inode *inode, int mask)
{
struct ovl_entry *oe;
struct dentry *alias = NULL;
struct inode *realinode;
struct dentry *realdentry;
bool is_upper;
int err;
if (S_ISDIR(inode->i_mode)) {
oe = inode->i_private;
} else if (mask & MAY_NOT_BLOCK) {
return -ECHILD;
} else {
/*
* For non-directories find an alias and get the info
* from there.
*/
alias = d_find_any_alias(inode);
if (WARN_ON(!alias))
return -ENOENT;
oe = alias->d_fsdata;
}
realdentry = ovl_entry_real(oe, &is_upper);
/* Careful in RCU walk mode */
realinode = ACCESS_ONCE(realdentry->d_inode);
if (!realinode) {
WARN_ON(!(mask & MAY_NOT_BLOCK));
err = -ENOENT;
goto out_dput;
}
if (mask & MAY_WRITE) {
umode_t mode = realinode->i_mode;
/*
* Writes will always be redirected to upper layer, so
* ignore lower layer being read-only.
*
* If the overlay itself is read-only then proceed
* with the permission check, don't return EROFS.
* This will only happen if this is the lower layer of
* another overlayfs.
*
* If upper fs becomes read-only after the overlay was
* constructed return EROFS to prevent modification of
* upper layer.
*/
err = -EROFS;
if (is_upper && !IS_RDONLY(inode) && IS_RDONLY(realinode) &&
(S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
goto out_dput;
}
err = __inode_permission(realinode, mask);
out_dput:
dput(alias);
return err;
}
