static int autofs4_getpath(struct autofs_sb_info *sbi,
struct dentry *dentry, char **name)
{
struct dentry *root = sbi->sb->s_root;
struct _dentry *tmp;
char *buf = *name;
char *p;
int len = 0;
struct _dentry *_dentry = tx_cache_get_dentry(dentry);
spin_lock(&dcache_lock);
for (tmp = tx_cache_get_dentry(dentry) ; parent(tmp) != root ;
tmp = tx_cache_get_dentry(tmp->d_parent))
len += tmp->d_name.len + 1;
if (--len > NAME_MAX) {
spin_unlock(&dcache_lock);
return 0;
}
*(buf + len) = '\0';
p = buf + len - _dentry->d_name.len;
strncpy(p, _dentry->d_name.name, _dentry->d_name.len);
for (tmp = tx_cache_get_dentry(_dentry->d_parent);
parent(tmp) != root ; tmp = tx_cache_get_dentry(tmp->d_parent)) {
*(--p) = '/';
p -= tmp->d_name.len;
strncpy(p, tmp->d_name.name, tmp->d_name.len);
}
spin_unlock(&dcache_lock);
return len;
}
static int oprofilefs_fill_super(struct super_block * sb, void * data, int silent)
{
struct inode * root_inode;
struct _inode * _root_inode;
struct dentry * root_dentry;
sb->s_blocksize = PAGE_CACHE_SIZE;
sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
sb->s_magic = OPROFILEFS_MAGIC;
sb->s_op = &s_ops;
sb->s_time_gran = 1;
root_inode = oprofilefs_get_inode(sb, S_IFDIR | 0755);
if (!root_inode)
return -ENOMEM;
_root_inode = tx_cache_get_inode(root_inode);
_root_inode->i_op = &simple_dir_inode_operations;
_root_inode->i_fop = &simple_dir_operations;
root_dentry = d_alloc_root(_root_inode);
if (!root_dentry) {
iput(root_inode);
return -ENOMEM;
}
sb->s_root = root_dentry;
oprofile_create_files(sb, tx_cache_get_dentry(root_dentry));
// FIXME: verify kill_litter_super removes our dentries
return 0;
}
static int
flush_write_buffer(struct dentry * dentry, struct configfs_buffer * buffer, size_t count)
{
struct configfs_attribute * attr = to_attr(dentry);
struct config_item * item = to_item(tx_cache_get_dentry(dentry)->d_parent);
struct configfs_item_operations * ops = buffer->ops;
return ops->store_attribute(item,attr,buffer->page,count);
}
int configfs_add_file(struct dentry * dir, const struct configfs_attribute * attr, int type)
{
struct configfs_dirent * parent_sd = dir->d_fsdata;
umode_t mode = (attr->ca_mode & S_IALLUGO) | S_IFREG;
int error = 0;
struct inode *inode = tx_cache_get_dentry(dir)->d_inode;
mutex_lock(&inode->i_mutex);
error = configfs_make_dirent(parent_sd, NULL, (void *) attr, mode, type);
mutex_unlock(&inode->i_mutex);
return error;
}
/*
* dentry_open() will have done dput(dentry) and mntput(mnt) if it returns an
* error.
*/
struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags)
{
int error;
struct file *f;
error = -ENFILE;
f = get_empty_filp();
if (f == NULL) {
dput(dentry);
mntput(mnt);
return ERR_PTR(error);
}
return __dentry_open(tx_cache_get_dentry(dentry), mnt, flags, f, NULL);
}
/**
* lookup_instantiate_filp - instantiates the open intent filp
* @nd: pointer to nameidata
* @dentry: pointer to dentry
* @open: open callback
*
* Helper for filesystems that want to use lookup open intents and pass back
* a fully instantiated struct file to the caller.
* This function is meant to be called from within a filesystem's
* lookup method.
* Beware of calling it for non-regular files! Those ->open methods might block
* (e.g. in fifo_open), leaving you with parent locked (and in case of fifo,
* leading to a deadlock, as nobody can open that fifo anymore, because
* another process to open fifo will block on locked parent when doing lookup).
* Note that in case of error, nd->intent.open.file is destroyed, but the
* path information remains valid.
* If the open callback is set to NULL, then the standard f_op->open()
* filesystem callback is substituted.
*/
struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry,
int (*open)(struct _inode *, struct file *))
{
if (IS_ERR(nd->intent.open.file))
goto out;
if (IS_ERR(dentry))
goto out_err;
nd->intent.open.file = __dentry_open(tx_cache_get_dentry(dget(dentry)),
mntget(nd->mnt),
nd->intent.open.flags - 1,
nd->intent.open.file,
open);
out:
return nd->intent.open.file;
out_err:
release_open_intent(nd);
nd->intent.open.file = (struct file *)dentry;
goto out;
}
/**
* fill_read_buffer - allocate and fill buffer from item.
* @dentry: dentry pointer.
* @buffer: data buffer for file.
*
* Allocate @buffer->page, if it hasn't been already, then call the
* config_item's show() method to fill the buffer with this attribute's
* data.
* This is called only once, on the file's first read.
*/
static int fill_read_buffer(struct dentry * dentry, struct configfs_buffer * buffer)
{
struct configfs_attribute * attr = to_attr(dentry);
struct config_item * item = to_item(tx_cache_get_dentry(dentry)->d_parent);
struct configfs_item_operations * ops = buffer->ops;
int ret = 0;
ssize_t count;
if (!buffer->page)
buffer->page = (char *) get_zeroed_page(GFP_KERNEL);
if (!buffer->page)
return -ENOMEM;
count = ops->show_attribute(item,attr,buffer->page);
buffer->needs_read_fill = 0;
BUG_ON(count > (ssize_t)PAGE_SIZE);
if (count >= 0)
buffer->count = count;
else
ret = count;
return ret;
}
/*
* Generic function to fsync a file.
*
* filp may be NULL if called via the msync of a vma.
*/
int file_fsync(struct file *filp, struct dentry *dentry, int datasync)
{
struct inode * inode = tx_cache_get_dentry(dentry)->d_inode;
struct super_block * sb;
int ret, err;
/* sync the inode to buffers */
ret = write_inode_now(inode, 0);
/* sync the superblock to buffers */
sb = tx_cache_get_inode_ro(inode)->i_sb;
lock_super(sb);
if (sb->s_op->write_super)
sb->s_op->write_super(sb);
unlock_super(sb);
/* .. finally sync the buffers to disk */
err = sync_blockdev(sb->s_bdev);
if (!ret)
ret = err;
return ret;
}
static struct _dentry * __oprofilefs_create_file(struct super_block * sb,
struct _dentry * root, char const * name, const struct file_operations * fops,
int perm)
{
struct dentry * dentry;
struct _dentry * _dentry;
struct inode * inode;
struct _inode * _inode;
dentry = d_alloc_name(root, name);
if (!dentry)
return NULL;
inode = oprofilefs_get_inode(sb, S_IFREG | perm);
if (!inode) {
dput(dentry);
return NULL;
}
_inode = tx_cache_get_inode(inode);
_inode->i_fop = fops;
_dentry = tx_cache_get_dentry(dentry);
d_add(_dentry, _inode);
return _dentry;
}
struct _dentry * oprofilefs_mkdir(struct super_block * sb,
struct _dentry * root, char const * name)
{
struct dentry * dentry;
struct _dentry * _dentry;
struct inode * inode;
struct _inode * _inode;
dentry = d_alloc_name(root, name);
if (!dentry)
return NULL;
inode = oprofilefs_get_inode(sb, S_IFDIR | 0755);
if (!inode) {
dput(dentry);
return NULL;
}
_inode = tx_cache_get_inode(inode);
_inode->i_op = &simple_dir_inode_operations;
_inode->i_fop = &simple_dir_operations;
_dentry = tx_cache_get_dentry(dentry);
d_add(_dentry, _inode);
return _dentry;
}
/**
* anon_inode_getfd - creates a new file instance by hooking it up to and
* anonymous inode, and a dentry that describe the "class"
* of the file
*
* @pfd: [out] pointer to the file descriptor
* @dpinode: [out] pointer to the inode
* @pfile: [out] pointer to the file struct
* @name: [in] name of the "class" of the new file
* @fops [in] file operations for the new file
* @priv [in] private data for the new file (will be file's private_data)
*
* Creates a new file by hooking it on a single inode. This is useful for files
* that do not need to have a full-fledged inode in order to operate correctly.
* All the files created with anon_inode_getfd() will share a single inode, by
* hence saving memory and avoiding code duplication for the file/inode/dentry
* setup.
*/
int anon_inode_getfd(int *pfd, struct inode **pinode, struct file **pfile,
const char *name, const struct file_operations *fops,
void *priv)
{
struct qstr this;
struct dentry *dentry;
struct _dentry *_dentry;
struct inode *inode;
struct _inode *_inode;
struct file *file;
struct _file *_file;
int error, fd;
if (IS_ERR(anon_inode_inode))
return -ENODEV;
file = get_empty_filp();
if (!file)
return -ENFILE;
_file = tx_cache_get_file(file);
inode = igrab(anon_inode_inode);
if (IS_ERR(inode)) {
error = PTR_ERR(inode);
goto err_put_filp;
}
_inode = tx_cache_get_inode(inode);
error = get_unused_fd();
if (error < 0)
goto err_iput;
fd = error;
/*
* Link the inode to a directory entry by creating a unique name
* using the inode sequence number.
*/
error = -ENOMEM;
this.name = name;
this.len = strlen(name);
this.hash = 0;
dentry = d_alloc(tx_cache_get_dentry(anon_inode_mnt->mnt_sb->s_root), &this);
if (!dentry)
goto err_put_unused_fd;
_dentry = tx_cache_get_dentry(dentry);
_dentry->d_op = &anon_inodefs_dentry_operations;
/* Do not publish this dentry inside the global dentry hash table */
_dentry->d_flags &= ~DCACHE_UNHASHED;
d_instantiate(_dentry, _inode);
_file->f_path.mnt = mntget(anon_inode_mnt);
_file->f_path.dentry = dentry;
file->f_mapping = _inode->i_mapping;
_file->f_pos = 0;
_file->f_flags = O_RDWR;
file->f_op = fops;
_file->f_mode = FMODE_READ | FMODE_WRITE;
_file->f_version = 0;
file->private_data = priv;
fd_install(fd, file);
*pfd = fd;
*pinode = inode;
*pfile = file;
return 0;
err_put_unused_fd:
put_unused_fd(fd);
err_iput:
iput(inode);
err_put_filp:
put_filp(file);
return error;
}
int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
enum autofs_notify notify)
{
struct autofs_info *ino;
struct autofs_wait_queue *wq;
char *name;
unsigned int len = 0;
unsigned int hash = 0;
int status, type;
/* In catatonic mode, we don't wait for nobody */
if (sbi->catatonic)
return -ENOENT;
name = kmalloc(NAME_MAX + 1, GFP_KERNEL);
if (!name)
return -ENOMEM;
/* If this is a direct mount request create a dummy name */
if (IS_ROOT(tx_cache_get_dentry(dentry)) && (sbi->type & AUTOFS_TYPE_DIRECT))
len = sprintf(name, "%p", dentry);
else {
len = autofs4_getpath(sbi, dentry, &name);
if (!len) {
kfree(name);
return -ENOENT;
}
}
hash = full_name_hash(name, len);
if (mutex_lock_interruptible(&sbi->wq_mutex)) {
kfree(name);
return -EINTR;
}
wq = autofs4_find_wait(sbi, name, hash, len);
ino = autofs4_dentry_ino(dentry);
if (!wq && ino && notify == NFY_NONE) {
/*
* Either we've betean the pending expire to post it's
* wait or it finished while we waited on the mutex.
* So we need to wait till either, the wait appears
* or the expire finishes.
*/
while (ino->flags & AUTOFS_INF_EXPIRING) {
mutex_unlock(&sbi->wq_mutex);
schedule_timeout_interruptible(HZ/10);
if (mutex_lock_interruptible(&sbi->wq_mutex)) {
kfree(name);
return -EINTR;
}
wq = autofs4_find_wait(sbi, name, hash, len);
if (wq)
break;
}
/*
* Not ideal but the status has already gone. Of the two
* cases where we wait on NFY_NONE neither depend on the
* return status of the wait.
*/
if (!wq) {
kfree(name);
mutex_unlock(&sbi->wq_mutex);
return 0;
}
}
if (!wq) {
/* Create a new wait queue */
wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL);
if (!wq) {
kfree(name);
mutex_unlock(&sbi->wq_mutex);
return -ENOMEM;
}
wq->wait_queue_token = autofs4_next_wait_queue;
if (++autofs4_next_wait_queue == 0)
autofs4_next_wait_queue = 1;
wq->next = sbi->queues;
sbi->queues = wq;
init_waitqueue_head(&wq->queue);
wq->hash = hash;
wq->name = name;
wq->len = len;
wq->dev = autofs4_get_dev(sbi);
wq->ino = autofs4_get_ino(sbi);
wq->uid = current->uid;
wq->gid = current->gid;
wq->pid = current->pid;
wq->tgid = current->tgid;
wq->status = -EINTR; /* Status return if interrupted */
atomic_set(&wq->wait_ctr, 2);
mutex_unlock(&sbi->wq_mutex);
if (sbi->version < 5) {
if (notify == NFY_MOUNT)
type = autofs_ptype_missing;
else
type = autofs_ptype_expire_multi;
} else {
if (notify == NFY_MOUNT)
type = (sbi->type & AUTOFS_TYPE_DIRECT) ?
autofs_ptype_missing_direct :
autofs_ptype_missing_indirect;
else
type = (sbi->type & AUTOFS_TYPE_DIRECT) ?
autofs_ptype_expire_direct :
autofs_ptype_expire_indirect;
}
DPRINTK("new wait id = 0x%08lx, name = %.*s, nfy=%d\n",
(unsigned long) wq->wait_queue_token, wq->len, wq->name, notify);
/* autofs4_notify_daemon() may block */
autofs4_notify_daemon(sbi, wq, type);
} else {
atomic_inc(&wq->wait_ctr);
mutex_unlock(&sbi->wq_mutex);
kfree(name);
DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d",
(unsigned long) wq->wait_queue_token, wq->len, wq->name, notify);
}
/* wq->name is NULL if and only if the lock is already released */
if (sbi->catatonic) {
/* We might have slept, so check again for catatonic mode */
wq->status = -ENOENT;
kfree(wq->name);
wq->name = NULL;
}
if (wq->name) {
/* Block all but "shutdown" signals while waiting */
sigset_t oldset;
unsigned long irqflags;
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
oldset = current->blocked;
siginitsetinv(¤t->blocked, SHUTDOWN_SIGS & ~oldset.sig[0]);
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
wait_event_interruptible(wq->queue, wq->name == NULL);
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
current->blocked = oldset;
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
} else {
DPRINTK("skipped sleeping");
}
status = wq->status;
/* Are we the last process to need status? */
if (atomic_dec_and_test(&wq->wait_ctr))
kfree(wq);
return status;
}