static int recv_fds(int minor, struct ancillary *data,
struct msg_control *msg_ctrl)
{
int rc, i, j;
struct msghdr msghdr;
struct cmsghdr *cmsg;
endpoint_t to_ep;
#if DEBUG == 1
static int call_count = 0;
printf("(uds) [%d] recv_fds() call_count=%d\n", minor,
++call_count);
#endif
msghdr.msg_control = msg_ctrl->msg_control;
msghdr.msg_controllen = msg_ctrl->msg_controllen;
cmsg = CMSG_FIRSTHDR(&msghdr);
cmsg->cmsg_len = CMSG_LEN(sizeof(int) * data->nfiledes);
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
to_ep = uds_fd_table[minor].owner;
/* copy to the target endpoint */
for (i = 0; i < data->nfiledes; i++) {
rc = copy_filp(to_ep, data->filps[i]);
if (rc < 0) {
/* revert set_filp() calls */
for (j = 0; j < data->nfiledes; j++) {
put_filp(data->filps[j]);
}
/* revert copy_filp() calls */
for (j = i; j >= 0; j--) {
cancel_fd(to_ep, data->fds[j]);
}
return rc;
}
data->fds[i] = rc; /* data->fds[i] now has the new FD */
}
for (i = 0; i < data->nfiledes; i++) {
put_filp(data->filps[i]);
#if DEBUG == 1
printf("(uds) recv_fds() => %d\n", data->fds[i]);
#endif
((int *)CMSG_DATA(cmsg))[i] = data->fds[i];
data->fds[i] = -1;
data->filps[i] = NULL;
}
data->nfiledes = 0;
return OK;
}
static int send_fds(int minor, struct ancillary *data)
{
int rc, i, j;
#if DEBUG == 1
static int call_count = 0;
printf("(uds) [%d] send_fds() call_count=%d\n", minor, ++call_count);
#endif
/* verify the file descriptors and get their filps. */
for (i = 0; i < data->nfiledes; i++) {
data->filps[i] = verify_fd(uds_fd_table[minor].owner,
data->fds[i]);
if (data->filps[i] == NULL) {
return EINVAL;
}
}
/* set them as in-flight */
for (i = 0; i < data->nfiledes; i++) {
rc = set_filp(data->filps[i]);
if (rc != OK) {
/* revert set_filp() calls */
for (j = i; j >= 0; j--) {
put_filp(data->filps[j]);
}
return rc;
}
}
return OK;
}
struct file *dentry_open(const struct path *path, int flags,
const struct cred *cred)
{
int error;
struct file *f;
validate_creds(cred);
BUG_ON(!path->mnt);
f = get_empty_filp();
if (!IS_ERR(f)) {
f->f_flags = flags;
f->f_path = *path;
error = do_dentry_open(f, NULL, cred);
if (!error) {
error = open_check_o_direct(f);
if (error) {
fput(f);
f = ERR_PTR(error);
}
} else {
put_filp(f);
f = ERR_PTR(error);
}
}
return f;
}
static struct file *vperfctr_get_filp(void)
{
struct file *filp;
struct inode *inode;
struct dentry *dentry;
filp = get_empty_filp();
if (!filp)
goto out;
inode = vperfctr_get_inode();
if (!inode)
goto out_filp;
dentry = vperfctr_d_alloc_root(inode);
if (!dentry)
goto out_inode;
filp->f_vfsmnt = mntget(vperfctr_mnt);
filp->f_dentry = dentry;
filp->f_mapping = dentry->d_inode->i_mapping;
filp->f_pos = 0;
filp->f_flags = 0;
filp->f_op = &vperfctr_file_ops; /* fops_get() if MODULE */
filp->f_mode = FMODE_READ;
filp->f_version = 0;
return filp;
out_inode:
iput(inode);
out_filp:
put_filp(filp); /* doesn't run ->release() like fput() does */
out:
return NULL;
}
struct file *dentry_open(const struct path *path, int flags,
const struct cred *cred)
{
int error;
struct file *f;
validate_creds(cred);
/* We must always pass in a valid mount pointer. */
BUG_ON(!path->mnt);
f = get_empty_filp();
if (!IS_ERR(f)) {
f->f_flags = flags;
f->f_path = *path;
error = do_dentry_open(f, NULL, cred);
if (!error) {
/* from now on we need fput() to dispose of f */
error = open_check_o_direct(f);
if (error) {
fput(f);
f = ERR_PTR(error);
}
} else {
put_filp(f);
f = ERR_PTR(error);
}
}
return f;
}
struct file *dentry_open(const struct path *path, int flags,
const struct cred *cred)
{
int error;
struct file *f;
validate_creds(cred);
/* We must always pass in a valid mount pointer. */
BUG_ON(!path->mnt);
error = -ENFILE;
f = get_empty_filp();
if (f == NULL)
return ERR_PTR(error);
f->f_flags = flags;
error = vfs_open(path, f, cred);
if (!error) {
error = open_check_o_direct(f);
if (error) {
fput(f);
f = ERR_PTR(error);
}
} else {
put_filp(f);
f = ERR_PTR(error);
}
return f;
}
int clear_fds(int minor, struct ancillary *data)
{
/* This function calls put_filp() for all of the FDs in data.
* This is used when a Unix Domain Socket is closed and there
* exists references to file descriptors that haven't been received
* with recvmsg().
*/
int i;
#if DEBUG == 1
static int call_count = 0;
printf("(uds) [%d] recv_fds() call_count=%d\n", minor,
++call_count);
#endif
for (i = 0; i < data->nfiledes; i++) {
put_filp(data->filps[i]);
#if DEBUG == 1
printf("(uds) clear_fds() => %d\n", data->fds[i]);
#endif
data->fds[i] = -1;
data->filps[i] = NULL;
}
data->nfiledes = 0;
return OK;
}
struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags)
{
struct file * f;
struct inode *inode;
int error;
error = -ENFILE;
f = get_empty_filp();
if (!f)
goto cleanup_dentry;
f->f_flags = flags;
f->f_mode = ((flags+1) & O_ACCMODE) | FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE;
inode = dentry->d_inode;
if (f->f_mode & FMODE_WRITE) {
error = get_write_access(inode);
if (error)
goto cleanup_file;
}
f->f_mapping = inode->i_mapping;
f->f_dentry = dentry;
f->f_vfsmnt = mnt;
f->f_pos = 0;
f->f_op = fops_get(inode->i_fop);
file_move(f, &inode->i_sb->s_files);
if (f->f_op && f->f_op->open) {
error = f->f_op->open(inode,f);
if (error)
goto cleanup_all;
}
f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping);
/* NB: we're sure to have correct a_ops only after f_op->open */
if (f->f_flags & O_DIRECT) {
if (!f->f_mapping->a_ops || !f->f_mapping->a_ops->direct_IO) {
fput(f);
f = ERR_PTR(-EINVAL);
}
}
return f;
cleanup_all:
fops_put(f->f_op);
if (f->f_mode & FMODE_WRITE)
put_write_access(inode);
file_kill(f);
f->f_dentry = NULL;
f->f_vfsmnt = NULL;
cleanup_file:
put_filp(f);
cleanup_dentry:
dput(dentry);
mntput(mnt);
return ERR_PTR(error);
}
/*
* shmem_file_setup - get an unlinked file living in tmpfs
*
* @name: name for dentry (to be seen in /proc/<pid>/maps
* @size: size to be set for the file
*
*/
struct file *shmem_file_setup(char *name, loff_t size, unsigned long flags)
{
int error;
struct file *file;
struct inode *inode;
struct dentry *dentry, *root;
struct qstr this;
if (IS_ERR(shm_mnt))
return (void *)shm_mnt;
error = -ENOMEM;
this.name = name;
this.len = strlen(name);
this.hash = 0; /* will go */
root = shm_mnt->mnt_root;
dentry = d_alloc(root, &this);
if (!dentry)
goto put_memory;
error = -ENFILE;
file = get_empty_filp();
if (!file)
goto put_dentry;
error = -ENOSPC;
inode = ramfs_get_inode(root->d_sb, S_IFREG | S_IRWXUGO, 0);
if (!inode)
goto close_file;
d_instantiate(dentry, inode);
inode->i_nlink = 0; /* It is unlinked */
file->f_path.mnt = mntget(shm_mnt);
file->f_path.dentry = dentry;
file->f_mapping = inode->i_mapping;
file->f_op = &ramfs_file_operations;
file->f_mode = FMODE_WRITE | FMODE_READ;
/* notify everyone as to the change of file size */
error = do_truncate(dentry, size, 0, file);
if (error < 0)
goto close_file;
return file;
close_file:
put_filp(file);
put_dentry:
dput(dentry);
put_memory:
return ERR_PTR(error);
}
int remove_physical_dir (struct file *file)
{
struct dentry *dentry;
struct inode *dir;
int res = 0;
dentry = file->f_dentry;
dir = dentry->d_parent->d_inode;
res = vfs_rmdir (dir, dentry);
dput (dentry);
put_filp (file);
return res;
}
struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags)
{
struct file * f;
struct inode *inode;
int error;
error = -ENFILE;
f = get_empty_filp();
if (!f)
goto cleanup_dentry;
f->f_flags = flags;
f->f_mode = (flags+1) & O_ACCMODE;
inode = dentry->d_inode;
if (f->f_mode & FMODE_WRITE) {
error = get_write_access(inode);
if (error)
goto cleanup_file;
}
f->f_dentry = dentry;
f->f_vfsmnt = mnt;
f->f_pos = 0;
f->f_reada = 0;
f->f_op = fops_get(inode->i_fop);
if (inode->i_sb)
file_move(f, &inode->i_sb->s_files);
if (f->f_op && f->f_op->open) {
error = f->f_op->open(inode,f);
if (error)
goto cleanup_all;
}
f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
return f;
cleanup_all:
fops_put(f->f_op);
if (f->f_mode & FMODE_WRITE)
put_write_access(inode);
f->f_dentry = NULL;
f->f_vfsmnt = NULL;
cleanup_file:
put_filp(f);
cleanup_dentry:
dput(dentry);
mntput(mnt);
return ERR_PTR(error);
}
static struct file *__dentry_open(struct path *path, struct file *f,
int (*open)(struct inode *, struct file *),
const struct cred *cred)
{
struct file *res = do_dentry_open(path, f, open, cred);
if (!IS_ERR(res)) {
int error = open_check_o_direct(f);
if (error) {
fput(res);
res = ERR_PTR(error);
}
} else {
put_filp(f);
}
return res;
}
struct file *filp_clone_open(struct file *oldfile)
{
struct file *file;
int retval;
file = get_empty_filp();
if (IS_ERR(file))
return file;
file->f_flags = oldfile->f_flags;
retval = vfs_open(&oldfile->f_path, file, oldfile->f_cred);
if (retval) {
put_filp(file);
return ERR_PTR(retval);
}
return file;
}
/*
* Note that while the flag value (low two bits) for sys_open means:
* 00 - read-only
* 01 - write-only
* 10 - read-write
* 11 - special
* it is changed into
* 00 - no permissions needed
* 01 - read-permission
* 10 - write-permission
* 11 - read-write
* for the internal routines (ie open_namei()/follow_link() etc). 00 is
* used by symlinks.
*/
struct file *filp_open(const char * filename, int flags, int mode)
{
int namei_flags, error;
struct nameidata nd;
struct file *f;
namei_flags = flags;
if ((namei_flags+1) & O_ACCMODE)
namei_flags++;
if (namei_flags & O_TRUNC)
namei_flags |= 2;
error = -ENFILE;
f = get_empty_filp();
if (f == NULL)
return ERR_PTR(error);
error = open_namei(filename, namei_flags, mode, &nd);
if (!error)
return __dentry_open(nd.dentry, nd.mnt, flags, f);
put_filp(f);
return ERR_PTR(error);
}
static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt,
struct file *f,
int (*open)(struct inode *, struct file *),
const struct cred *cred)
{
static const struct file_operations empty_fops = {};
struct inode *inode;
int error;
f->f_mode = OPEN_FMODE(f->f_flags) | FMODE_LSEEK |
FMODE_PREAD | FMODE_PWRITE;
if (unlikely(f->f_flags & O_PATH))
f->f_mode = FMODE_PATH;
inode = dentry->d_inode;
if (f->f_mode & FMODE_WRITE) {
error = __get_file_write_access(inode, mnt);
if (error)
goto cleanup_file;
if (!special_file(inode->i_mode))
file_take_write(f);
}
f->f_mapping = inode->i_mapping;
f->f_path.dentry = dentry;
f->f_path.mnt = mnt;
f->f_pos = 0;
file_sb_list_add(f, inode->i_sb);
if (unlikely(f->f_mode & FMODE_PATH)) {
f->f_op = &empty_fops;
return f;
}
f->f_op = fops_get(inode->i_fop);
error = security_dentry_open(f, cred);
if (error)
goto cleanup_all;
error = break_lease(inode, f->f_flags);
if (error)
goto cleanup_all;
if (!open && f->f_op)
open = f->f_op->open;
if (open) {
error = open(inode, f);
if (error)
goto cleanup_all;
}
if ((f->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
i_readcount_inc(inode);
f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping);
/* NB: we're sure to have correct a_ops only after f_op->open */
if (f->f_flags & O_DIRECT) {
if (!f->f_mapping->a_ops ||
((!f->f_mapping->a_ops->direct_IO) &&
(!f->f_mapping->a_ops->get_xip_mem))) {
fput(f);
f = ERR_PTR(-EINVAL);
}
}
return f;
cleanup_all:
fops_put(f->f_op);
if (f->f_mode & FMODE_WRITE) {
put_write_access(inode);
if (!special_file(inode->i_mode)) {
/*
* We don't consider this a real
* mnt_want/drop_write() pair
* because it all happenend right
* here, so just reset the state.
*/
file_reset_write(f);
mnt_drop_write(mnt);
}
}
file_sb_list_del(f);
f->f_path.dentry = NULL;
f->f_path.mnt = NULL;
cleanup_file:
put_filp(f);
dput(dentry);
mntput(mnt);
return ERR_PTR(error);
}
static struct file *__dentry_open(struct _dentry *dentry, struct vfsmount *mnt,
int flags, struct file *f,
int (*open)(struct _inode *, struct file *))
{
struct _inode *inode;
int error;
struct super_block *sb;
struct _file *_f = tx_cache_get_file(f);
_f->f_flags = flags;
_f->f_mode = ((flags+1) & O_ACCMODE) | FMODE_LSEEK |
FMODE_PREAD | FMODE_PWRITE;
inode = d_get_inode(dentry);
sb = inode->i_sb;
if (_f->f_mode & FMODE_WRITE) {
error = get_write_access(parent(inode));
if (error)
goto cleanup_file;
}
f->f_mapping = inode->i_mapping;
_f->f_path.dentry = parent(dentry);
_f->f_path.mnt = mnt;
_f->f_pos = 0;
f->f_op = fops_get(inode->i_fop);
file_move(f, &sb->s_files);
if (!open && f->f_op)
open = f->f_op->open;
if (open) {
error = open(inode, f);
if (error)
goto cleanup_all;
}
_f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
file_ra_state_init(&f->f_ra,
tx_cache_get_inode(f->f_mapping->host)->i_mapping);
/* NB: we're sure to have correct a_ops only after f_op->open */
if (_f->f_flags & O_DIRECT) {
if (!f->f_mapping->a_ops ||
((!f->f_mapping->a_ops->direct_IO) &&
(!f->f_mapping->a_ops->get_xip_page))) {
fput(f);
f = ERR_PTR(-EINVAL);
}
}
return f;
cleanup_all:
fops_put(f->f_op);
if (_f->f_mode & FMODE_WRITE)
put_write_access(parent(inode));
file_kill(f);
_f->f_path.dentry = NULL;
_f->f_path.mnt = NULL;
cleanup_file:
/* Avoid issues if we recycle this object */
if(live_transaction())
early_release(&f->xobj, 1);
put_filp(f);
dput(parent(dentry));
mntput(mnt);
return ERR_PTR(error);
}
int do_pipe(int *fd)
{
struct inode * inode;
struct file *f1, *f2;
int error;
int i,j;
error = -ENFILE;
f1 = get_empty_filp();
if (!f1)
goto no_files;
f2 = get_empty_filp();
if (!f2)
goto close_f1;
inode = get_pipe_inode();
if (!inode)
goto close_f12;
error = get_unused_fd();
if (error < 0)
goto close_f12_inode;
i = error;
error = get_unused_fd();
if (error < 0)
goto close_f12_inode_i;
j = error;
error = -ENOMEM;
f1->f_dentry = f2->f_dentry = dget(d_alloc_root(inode, NULL));
if (!f1->f_dentry)
goto close_f12_inode_i_j;
/* read file */
f1->f_pos = f2->f_pos = 0;
f1->f_flags = O_RDONLY;
f1->f_op = &read_pipe_fops;
f1->f_mode = 1;
/* write file */
f2->f_flags = O_WRONLY;
f2->f_op = &write_pipe_fops;
f2->f_mode = 2;
fd_install(i, f1);
fd_install(j, f2);
fd[0] = i;
fd[1] = j;
return 0;
close_f12_inode_i_j:
put_unused_fd(j);
close_f12_inode_i:
put_unused_fd(i);
close_f12_inode:
free_page((unsigned long) PIPE_BASE(*inode));
iput(inode);
close_f12:
put_filp(f2);
close_f1:
put_filp(f1);
no_files:
return error;
}
/**
* 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;
}
static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags, struct file *f)
{
struct inode *inode;
static LIST_HEAD(kill_list);
int error;
f->f_flags = flags;
f->f_mode = (flags+1) & O_ACCMODE;
inode = dentry->d_inode;
if (f->f_mode & FMODE_WRITE) {
error = get_write_access(inode);
if (error)
goto cleanup_file;
}
f->f_dentry = dentry;
f->f_vfsmnt = mnt;
f->f_pos = 0;
f->f_reada = 0;
f->f_op = fops_get(inode->i_fop);
file_move(f, &inode->i_sb->s_files);
/* preallocate kiobuf for O_DIRECT */
f->f_iobuf = NULL;
f->f_iobuf_lock = 0;
if (f->f_flags & O_DIRECT) {
error = alloc_kiovec(1, &f->f_iobuf);
if (error)
goto cleanup_all;
}
if (f->f_op && f->f_op->open) {
error = f->f_op->open(inode,f);
if (error)
goto cleanup_all;
}
f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
/* NB: we're sure to have correct a_ops only after f_op->open */
if (f->f_flags & O_DIRECT) {
if (!inode->i_mapping || !inode->i_mapping->a_ops ||
!(inode->i_mapping->a_ops->direct_IO ||
inode->i_mapping->a_ops->direct_sector_IO)) {
fput(f);
f = ERR_PTR(-EINVAL);
}
}
return f;
cleanup_all:
if (f->f_iobuf)
free_kiovec(1, &f->f_iobuf);
fops_put(f->f_op);
if (f->f_mode & FMODE_WRITE)
put_write_access(inode);
file_move(f, &kill_list); /* out of the way.. */
f->f_dentry = NULL;
f->f_vfsmnt = NULL;
cleanup_file:
put_filp(f);
dput(dentry);
mntput(mnt);
return ERR_PTR(error);
}
static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt,
int flags, struct file *f,
int (*open)(struct inode *, struct file *))
{
struct inode *inode;
int error;
f->f_flags = flags;
f->f_mode = ((flags+1) & O_ACCMODE) | FMODE_LSEEK |
FMODE_PREAD | FMODE_PWRITE;
inode = dentry->d_inode;
if (f->f_mode & FMODE_WRITE) {
error = __get_file_write_access(inode, mnt);
if (error)
goto cleanup_file;
if (!special_file(inode->i_mode))
file_take_write(f);
}
f->f_mapping = inode->i_mapping;
f->f_path.dentry = dentry;
f->f_path.mnt = mnt;
f->f_pos = 0;
f->f_op = fops_get(inode->i_fop);
file_move(f, &inode->i_sb->s_files);
error = security_dentry_open(f);
if (error)
goto cleanup_all;
if (!open && f->f_op)
open = f->f_op->open;
if (open) {
error = open(inode, f);
if (error)
goto cleanup_all;
}
f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping);
/* NB: we're sure to have correct a_ops only after f_op->open */
if (f->f_flags & O_DIRECT) {
if (!f->f_mapping->a_ops ||
((!f->f_mapping->a_ops->direct_IO) &&
(!f->f_mapping->a_ops->get_xip_mem))) {
fput(f);
f = ERR_PTR(-EINVAL);
}
}
return f;
cleanup_all:
fops_put(f->f_op);
if (f->f_mode & FMODE_WRITE) {
put_write_access(inode);
if (!special_file(inode->i_mode)) {
/*
* We don't consider this a real
* mnt_want/drop_write() pair
* because it all happenend right
* here, so just reset the state.
*/
file_reset_write(f);
mnt_drop_write(mnt);
}
}
file_kill(f);
f->f_path.dentry = NULL;
f->f_path.mnt = NULL;
cleanup_file:
put_filp(f);
dput(dentry);
mntput(mnt);
return ERR_PTR(error);
}
/**
* 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 *))
{
struct path path = { .dentry = dentry, .mnt = nd->path.mnt };
const struct cred *cred = current_cred();
if (IS_ERR(nd->intent.open.file))
goto out;
if (IS_ERR(dentry))
goto out_err;
nd->intent.open.file = __dentry_open(&path, nd->intent.open.file,
open, cred);
out:
return nd->intent.open.file;
out_err:
release_open_intent(nd);
nd->intent.open.file = (struct file *)dentry;
goto out;
}
EXPORT_SYMBOL_GPL(lookup_instantiate_filp);
/**
* nameidata_to_filp - convert a nameidata to an open filp.
* @nd: pointer to nameidata
* @flags: open flags
*
* Note that this function destroys the original nameidata
*/
struct file *nameidata_to_filp(struct nameidata *nd)
{
const struct cred *cred = current_cred();
struct file *filp;
/* Pick up the filp from the open intent */
filp = nd->intent.open.file;
nd->intent.open.file = NULL;
/* Has the filesystem initialised the file for us? */
if (filp->f_path.dentry == NULL) {
struct inode *inode = nd->path.dentry->d_inode;
if (inode->i_op->open) {
int flags = filp->f_flags;
put_filp(filp);
filp = inode->i_op->open(nd->path.dentry, flags, cred);
} else {
filp = __dentry_open(&nd->path, filp, NULL, cred);
}
}
return filp;
}
/*
* 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,
const struct cred *cred)
{
struct path path = { .dentry = dentry, .mnt = mnt };
struct file *ret;
/* We must always pass in a valid mount pointer. */
BUG_ON(!mnt);
ret = vfs_open(&path, flags, cred);
path_put(&path);
return ret;
}
EXPORT_SYMBOL(dentry_open);
/**
* vfs_open - open the file at the given path
* @path: path to open
* @flags: open flags
* @cred: credentials to use
*
* Open the file. If successful, the returned file will have acquired
* an additional reference for path.
*/
struct file *vfs_open(struct path *path, int flags, const struct cred *cred)
{
struct file *f;
struct inode *inode = path->dentry->d_inode;
validate_creds(cred);
if (inode->i_op->open)
return inode->i_op->open(path->dentry, flags, cred);
f = get_empty_filp();
if (f == NULL)
return ERR_PTR(-ENFILE);
f->f_flags = flags;
return __dentry_open(path, f, NULL, cred);
}
EXPORT_SYMBOL(vfs_open);
static void __put_unused_fd(struct files_struct *files, unsigned int fd)
{
struct fdtable *fdt = files_fdtable(files);
__FD_CLR(fd, fdt->open_fds);
if (fd < files->next_fd)
files->next_fd = fd;
}
void put_unused_fd(unsigned int fd)
{
struct files_struct *files = current->files;
spin_lock(&files->file_lock);
__put_unused_fd(files, fd);
spin_unlock(&files->file_lock);
}
EXPORT_SYMBOL(put_unused_fd);
/*
* Install a file pointer in the fd array.
*
* The VFS is full of places where we drop the files lock between
* setting the open_fds bitmap and installing the file in the file
* array. At any such point, we are vulnerable to a dup2() race
* installing a file in the array before us. We need to detect this and
* fput() the struct file we are about to overwrite in this case.
*
* It should never happen - if we allow dup2() do it, _really_ bad things
* will follow.
*/
void fd_install(unsigned int fd, struct file *file)
{
struct files_struct *files = current->files;
struct fdtable *fdt;
spin_lock(&files->file_lock);
fdt = files_fdtable(files);
BUG_ON(fdt->fd[fd] != NULL);
rcu_assign_pointer(fdt->fd[fd], file);
spin_unlock(&files->file_lock);
}
EXPORT_SYMBOL(fd_install);
static inline int build_open_flags(int flags, int mode, struct open_flags *op)
{
int lookup_flags = 0;
int acc_mode;
if (!(flags & O_CREAT))
mode = 0;
op->mode = mode;
/* Must never be set by userspace */
flags &= ~FMODE_NONOTIFY;
/*
* O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only
* check for O_DSYNC if the need any syncing at all we enforce it's
* always set instead of having to deal with possibly weird behaviour
* for malicious applications setting only __O_SYNC.
*/
if (flags & __O_SYNC)
flags |= O_DSYNC;
/*
* If we have O_PATH in the open flag. Then we
* cannot have anything other than the below set of flags
*/
if (flags & O_PATH) {
flags &= O_DIRECTORY | O_NOFOLLOW | O_PATH;
acc_mode = 0;
} else {
acc_mode = MAY_OPEN | ACC_MODE(flags);
}
op->open_flag = flags;
/* O_TRUNC implies we need access checks for write permissions */
if (flags & O_TRUNC)
acc_mode |= MAY_WRITE;
/* Allow the LSM permission hook to distinguish append
access from general write access. */
if (flags & O_APPEND)
acc_mode |= MAY_APPEND;
op->acc_mode = acc_mode;
op->intent = flags & O_PATH ? 0 : LOOKUP_OPEN;
if (flags & O_CREAT) {
op->intent |= LOOKUP_CREATE;
if (flags & O_EXCL)
op->intent |= LOOKUP_EXCL;
}
if (flags & O_DIRECTORY)
lookup_flags |= LOOKUP_DIRECTORY;
if (!(flags & O_NOFOLLOW))
lookup_flags |= LOOKUP_FOLLOW;
return lookup_flags;
}
int do_pipe(int *fd)
{
struct qstr this;
char name[32];
struct dentry *dentry;
struct inode * inode;
struct file *f1, *f2;
int error;
int i,j;
error = -ENFILE;
f1 = get_empty_filp();
if (!f1)
goto no_files;
f2 = get_empty_filp();
if (!f2)
goto close_f1;
inode = get_pipe_inode();
if (!inode)
goto close_f12;
error = get_unused_fd();
if (error < 0)
goto close_f12_inode;
i = error;
error = get_unused_fd();
if (error < 0)
goto close_f12_inode_i;
j = error;
error = -ENOMEM;
sprintf(name, "[%lu]", inode->i_ino);
this.name = name;
this.len = strlen(name);
this.hash = inode->i_ino; /* will go */
dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &this);
if (!dentry)
goto close_f12_inode_i_j;
dentry->d_op = &pipefs_dentry_operations;
d_add(dentry, inode);
f1->f_vfsmnt = f2->f_vfsmnt = mntget(mntget(pipe_mnt));
f1->f_dentry = f2->f_dentry = dget(dentry);
/* read file */
f1->f_pos = f2->f_pos = 0;
f1->f_flags = O_RDONLY;
f1->f_op = &read_pipe_fops;
f1->f_mode = 1;
f1->f_version = 0;
/* write file */
f2->f_flags = O_WRONLY;
f2->f_op = &write_pipe_fops;
f2->f_mode = 2;
f2->f_version = 0;
fd_install(i, f1);
fd_install(j, f2);
fd[0] = i;
fd[1] = j;
return 0;
close_f12_inode_i_j:
put_unused_fd(j);
close_f12_inode_i:
put_unused_fd(i);
close_f12_inode:
free_page((unsigned long) PIPE_BASE(*inode));
kfree(inode->i_pipe);
inode->i_pipe = NULL;
iput(inode);
close_f12:
put_filp(f2);
close_f1:
put_filp(f1);
no_files:
return error;
}
struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags)
{
struct file * f;
struct inode *inode;
static LIST_HEAD(kill_list);
int error;
error = -ENFILE;
f = get_empty_filp();
if (!f)
goto cleanup_dentry;
f->f_flags = flags;
f->f_mode = (flags+1) & O_ACCMODE;
inode = dentry->d_inode;
if (f->f_mode & FMODE_WRITE) {
error = get_write_access(inode);
if (error)
goto cleanup_file;
}
f->f_dentry = dentry;
f->f_vfsmnt = mnt;
f->f_pos = 0;
f->f_reada = 0;
f->f_op = fops_get(inode->i_fop);
file_move(f, &inode->i_sb->s_files);
/* preallocate kiobuf for O_DIRECT */
f->f_iobuf = NULL;
f->f_iobuf_lock = 0;
if (f->f_flags & O_DIRECT) {
error = alloc_kiovec(1, &f->f_iobuf);
if (error)
goto cleanup_all;
}
if (f->f_op && f->f_op->open) {
error = f->f_op->open(inode,f);
if (error)
goto cleanup_all;
}
f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
return f;
cleanup_all:
if (f->f_iobuf)
free_kiovec(1, &f->f_iobuf);
fops_put(f->f_op);
if (f->f_mode & FMODE_WRITE)
put_write_access(inode);
file_move(f, &kill_list); /* out of the way.. */
f->f_dentry = NULL;
f->f_vfsmnt = NULL;
cleanup_file:
put_filp(f);
cleanup_dentry:
dput(dentry);
mntput(mnt);
return ERR_PTR(error);
}
