{
int err;
+ if (IS_ERR(name))
+ return PTR_ERR(name);
while (*name=='/')
name++;
if (!*name)
}
}
+/* must be paired with terminate_walk() */
static const char *path_init(struct nameidata *nd, unsigned flags)
{
const char *s = nd->name->name;
if (!*s)
flags &= ~LOOKUP_RCU;
+ if (flags & LOOKUP_RCU)
+ rcu_read_lock();
nd->last_type = LAST_ROOT; /* if there are only slashes... */
nd->flags = flags | LOOKUP_JUMPED | LOOKUP_PARENT;
nd->path = nd->root;
nd->inode = inode;
if (flags & LOOKUP_RCU) {
- rcu_read_lock();
nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq);
nd->root_seq = nd->seq;
nd->m_seq = read_seqbegin(&mount_lock);
nd->m_seq = read_seqbegin(&mount_lock);
if (*s == '/') {
- if (flags & LOOKUP_RCU)
- rcu_read_lock();
set_root(nd);
if (likely(!nd_jump_root(nd)))
return s;
- nd->root.mnt = NULL;
- rcu_read_unlock();
return ERR_PTR(-ECHILD);
} else if (nd->dfd == AT_FDCWD) {
if (flags & LOOKUP_RCU) {
struct fs_struct *fs = current->fs;
unsigned seq;
- rcu_read_lock();
-
do {
seq = read_seqcount_begin(&fs->seq);
nd->path = fs->pwd;
dentry = f.file->f_path.dentry;
- if (*s) {
- if (!d_can_lookup(dentry)) {
- fdput(f);
- return ERR_PTR(-ENOTDIR);
- }
+ if (*s && unlikely(!d_can_lookup(dentry))) {
+ fdput(f);
+ return ERR_PTR(-ENOTDIR);
}
nd->path = f.file->f_path;
if (flags & LOOKUP_RCU) {
- rcu_read_lock();
nd->inode = nd->path.dentry->d_inode;
nd->seq = read_seqcount_begin(&nd->path.dentry->d_seq);
} else {
const char *s = path_init(nd, flags);
int err;
- if (IS_ERR(s))
- return PTR_ERR(s);
-
- if (unlikely(flags & LOOKUP_DOWN)) {
+ if (unlikely(flags & LOOKUP_DOWN) && !IS_ERR(s)) {
err = handle_lookup_down(nd);
- if (unlikely(err < 0)) {
- terminate_walk(nd);
- return err;
- }
+ if (unlikely(err < 0))
+ s = ERR_PTR(err);
}
while (!(err = link_path_walk(s, nd))
&& ((err = lookup_last(nd)) > 0)) {
s = trailing_symlink(nd);
- if (IS_ERR(s)) {
- err = PTR_ERR(s);
- break;
- }
}
if (!err)
err = complete_walk(nd);
struct path *parent)
{
const char *s = path_init(nd, flags);
- int err;
- if (IS_ERR(s))
- return PTR_ERR(s);
- err = link_path_walk(s, nd);
+ int err = link_path_walk(s, nd);
if (!err)
err = complete_walk(nd);
if (!err) {
{
const char *s = path_init(nd, flags);
int err;
- if (IS_ERR(s))
- return PTR_ERR(s);
+
while (!(err = link_path_walk(s, nd)) &&
(err = mountpoint_last(nd)) > 0) {
s = trailing_symlink(nd);
- if (IS_ERR(s)) {
- err = PTR_ERR(s);
- break;
- }
}
if (!err) {
*path = nd->path;
* Returns 0 if successful. The file will have been created and attached to
* @file by the filesystem calling finish_open().
*
- * Returns 1 if the file was looked up only or didn't need creating. The
- * caller will need to perform the open themselves. @path will have been
- * updated to point to the new dentry. This may be negative.
+ * If the file was looked up only or didn't need creating, FMODE_OPENED won't
+ * be set. The caller will need to perform the open themselves. @path will
+ * have been updated to point to the new dentry. This may be negative.
*
* Returns an error code otherwise.
*/
static int atomic_open(struct nameidata *nd, struct dentry *dentry,
struct path *path, struct file *file,
const struct open_flags *op,
- int open_flag, umode_t mode,
- int *opened)
+ int open_flag, umode_t mode)
{
struct dentry *const DENTRY_NOT_SET = (void *) -1UL;
struct inode *dir = nd->path.dentry->d_inode;
file->f_path.dentry = DENTRY_NOT_SET;
file->f_path.mnt = nd->path.mnt;
error = dir->i_op->atomic_open(dir, dentry, file,
- open_to_namei_flags(open_flag),
- mode, opened);
+ open_to_namei_flags(open_flag), mode);
d_lookup_done(dentry);
if (!error) {
- /*
- * We didn't have the inode before the open, so check open
- * permission here.
- */
- int acc_mode = op->acc_mode;
- if (*opened & FILE_CREATED) {
- WARN_ON(!(open_flag & O_CREAT));
- fsnotify_create(dir, dentry);
- acc_mode = 0;
- }
- error = may_open(&file->f_path, acc_mode, open_flag);
- if (WARN_ON(error > 0))
- error = -EINVAL;
- } else if (error > 0) {
- if (WARN_ON(file->f_path.dentry == DENTRY_NOT_SET)) {
+ if (file->f_mode & FMODE_OPENED) {
+ /*
+ * We didn't have the inode before the open, so check open
+ * permission here.
+ */
+ int acc_mode = op->acc_mode;
+ if (file->f_mode & FMODE_CREATED) {
+ WARN_ON(!(open_flag & O_CREAT));
+ fsnotify_create(dir, dentry);
+ acc_mode = 0;
+ }
+ error = may_open(&file->f_path, acc_mode, open_flag);
+ if (WARN_ON(error > 0))
+ error = -EINVAL;
+ } else if (WARN_ON(file->f_path.dentry == DENTRY_NOT_SET)) {
error = -EIO;
} else {
if (file->f_path.dentry) {
dput(dentry);
dentry = file->f_path.dentry;
}
- if (*opened & FILE_CREATED)
+ if (file->f_mode & FMODE_CREATED)
fsnotify_create(dir, dentry);
if (unlikely(d_is_negative(dentry))) {
error = -ENOENT;
} else {
path->dentry = dentry;
path->mnt = nd->path.mnt;
- return 1;
+ return 0;
}
}
}
/*
* Look up and maybe create and open the last component.
*
- * Must be called with i_mutex held on parent.
- *
- * Returns 0 if the file was successfully atomically created (if necessary) and
- * opened. In this case the file will be returned attached to @file.
- *
- * Returns 1 if the file was not completely opened at this time, though lookups
- * and creations will have been performed and the dentry returned in @path will
- * be positive upon return if O_CREAT was specified. If O_CREAT wasn't
- * specified then a negative dentry may be returned.
+ * Must be called with parent locked (exclusive in O_CREAT case).
*
- * An error code is returned otherwise.
+ * Returns 0 on success, that is, if
+ * the file was successfully atomically created (if necessary) and opened, or
+ * the file was not completely opened at this time, though lookups and
+ * creations were performed.
+ * These case are distinguished by presence of FMODE_OPENED on file->f_mode.
+ * In the latter case dentry returned in @path might be negative if O_CREAT
+ * hadn't been specified.
*
- * FILE_CREATE will be set in @*opened if the dentry was created and will be
- * cleared otherwise prior to returning.
+ * An error code is returned on failure.
*/
static int lookup_open(struct nameidata *nd, struct path *path,
struct file *file,
const struct open_flags *op,
- bool got_write, int *opened)
+ bool got_write)
{
struct dentry *dir = nd->path.dentry;
struct inode *dir_inode = dir->d_inode;
if (unlikely(IS_DEADDIR(dir_inode)))
return -ENOENT;
- *opened &= ~FILE_CREATED;
+ file->f_mode &= ~FMODE_CREATED;
dentry = d_lookup(dir, &nd->last);
for (;;) {
if (!dentry) {
if (dir_inode->i_op->atomic_open) {
error = atomic_open(nd, dentry, path, file, op, open_flag,
- mode, opened);
+ mode);
if (unlikely(error == -ENOENT) && create_error)
error = create_error;
return error;
/* Negative dentry, just create the file */
if (!dentry->d_inode && (open_flag & O_CREAT)) {
- *opened |= FILE_CREATED;
+ file->f_mode |= FMODE_CREATED;
audit_inode_child(dir_inode, dentry, AUDIT_TYPE_CHILD_CREATE);
if (!dir_inode->i_op->create) {
error = -EACCES;
out_no_open:
path->dentry = dentry;
path->mnt = nd->path.mnt;
- return 1;
+ return 0;
out_dput:
dput(dentry);
* Handle the last step of open()
*/
static int do_last(struct nameidata *nd,
- struct file *file, const struct open_flags *op,
- int *opened)
+ struct file *file, const struct open_flags *op)
{
struct dentry *dir = nd->path.dentry;
int open_flag = op->open_flag;
inode_lock(dir->d_inode);
else
inode_lock_shared(dir->d_inode);
- error = lookup_open(nd, &path, file, op, got_write, opened);
+ error = lookup_open(nd, &path, file, op, got_write);
if (open_flag & O_CREAT)
inode_unlock(dir->d_inode);
else
inode_unlock_shared(dir->d_inode);
- if (error <= 0) {
- if (error)
- goto out;
+ if (error)
+ goto out;
- if ((*opened & FILE_CREATED) ||
+ if (file->f_mode & FMODE_OPENED) {
+ if ((file->f_mode & FMODE_CREATED) ||
!S_ISREG(file_inode(file)->i_mode))
will_truncate = false;
goto opened;
}
- if (*opened & FILE_CREATED) {
+ if (file->f_mode & FMODE_CREATED) {
/* Don't check for write permission, don't truncate */
open_flag &= ~O_TRUNC;
will_truncate = false;
error = may_open(&nd->path, acc_mode, open_flag);
if (error)
goto out;
- BUG_ON(*opened & FILE_OPENED); /* once it's opened, it's opened */
- error = vfs_open(&nd->path, file, current_cred());
+ BUG_ON(file->f_mode & FMODE_OPENED); /* once it's opened, it's opened */
+ error = vfs_open(&nd->path, file);
if (error)
goto out;
- *opened |= FILE_OPENED;
opened:
- error = open_check_o_direct(file);
- if (!error)
- error = ima_file_check(file, op->acc_mode, *opened);
+ error = ima_file_check(file, op->acc_mode);
if (!error && will_truncate)
error = handle_truncate(file);
out:
- if (unlikely(error) && (*opened & FILE_OPENED))
- fput(file);
if (unlikely(error > 0)) {
WARN_ON(1);
error = -EINVAL;
static int do_tmpfile(struct nameidata *nd, unsigned flags,
const struct open_flags *op,
- struct file *file, int *opened)
+ struct file *file)
{
struct dentry *child;
struct path path;
if (error)
goto out2;
file->f_path.mnt = path.mnt;
- error = finish_open(file, child, NULL, opened);
- if (error)
- goto out2;
- error = open_check_o_direct(file);
- if (error)
- fput(file);
+ error = finish_open(file, child, NULL);
out2:
mnt_drop_write(path.mnt);
out:
int error = path_lookupat(nd, flags, &path);
if (!error) {
audit_inode(nd->name, path.dentry, 0);
- error = vfs_open(&path, file, current_cred());
+ error = vfs_open(&path, file);
path_put(&path);
}
return error;
static struct file *path_openat(struct nameidata *nd,
const struct open_flags *op, unsigned flags)
{
- const char *s;
struct file *file;
- int opened = 0;
int error;
- file = get_empty_filp();
+ file = alloc_empty_file(op->open_flag, current_cred());
if (IS_ERR(file))
return file;
- file->f_flags = op->open_flag;
-
if (unlikely(file->f_flags & __O_TMPFILE)) {
- error = do_tmpfile(nd, flags, op, file, &opened);
- goto out2;
- }
-
- if (unlikely(file->f_flags & O_PATH)) {
+ error = do_tmpfile(nd, flags, op, file);
+ } else if (unlikely(file->f_flags & O_PATH)) {
error = do_o_path(nd, flags, file);
- if (!error)
- opened |= FILE_OPENED;
- goto out2;
- }
-
- s = path_init(nd, flags);
- if (IS_ERR(s)) {
- put_filp(file);
- return ERR_CAST(s);
- }
- while (!(error = link_path_walk(s, nd)) &&
- (error = do_last(nd, file, op, &opened)) > 0) {
- nd->flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL);
- s = trailing_symlink(nd);
- if (IS_ERR(s)) {
- error = PTR_ERR(s);
- break;
+ } else {
+ const char *s = path_init(nd, flags);
+ while (!(error = link_path_walk(s, nd)) &&
+ (error = do_last(nd, file, op)) > 0) {
+ nd->flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL);
+ s = trailing_symlink(nd);
}
+ terminate_walk(nd);
}
- terminate_walk(nd);
-out2:
- if (!(opened & FILE_OPENED)) {
- BUG_ON(!error);
- put_filp(file);
+ if (likely(!error)) {
+ if (likely(file->f_mode & FMODE_OPENED))
+ return file;
+ WARN_ON(1);
+ error = -EINVAL;
}
- if (unlikely(error)) {
- if (error == -EOPENSTALE) {
- if (flags & LOOKUP_RCU)
- error = -ECHILD;
- else
- error = -ESTALE;
- }
- file = ERR_PTR(error);
+ fput(file);
+ if (error == -EOPENSTALE) {
+ if (flags & LOOKUP_RCU)
+ error = -ECHILD;
+ else
+ error = -ESTALE;
}
- return file;
+ return ERR_PTR(error);
}
struct file *do_filp_open(int dfd, struct filename *pathname,
return len;
}
-/*
- * A helper for ->readlink(). This should be used *ONLY* for symlinks that
- * have ->get_link() not calling nd_jump_link(). Using (or not using) it
- * for any given inode is up to filesystem.
- */
-static int generic_readlink(struct dentry *dentry, char __user *buffer,
- int buflen)
-{
- DEFINE_DELAYED_CALL(done);
- struct inode *inode = d_inode(dentry);
- const char *link = inode->i_link;
- int res;
-
- if (!link) {
- link = inode->i_op->get_link(dentry, inode, &done);
- if (IS_ERR(link))
- return PTR_ERR(link);
- }
- res = readlink_copy(buffer, buflen, link);
- do_delayed_call(&done);
- return res;
-}
-
/**
* vfs_readlink - copy symlink body into userspace buffer
* @dentry: dentry on which to get symbolic link
int vfs_readlink(struct dentry *dentry, char __user *buffer, int buflen)
{
struct inode *inode = d_inode(dentry);
+ DEFINE_DELAYED_CALL(done);
+ const char *link;
+ int res;
if (unlikely(!(inode->i_opflags & IOP_DEFAULT_READLINK))) {
if (unlikely(inode->i_op->readlink))
spin_unlock(&inode->i_lock);
}
- return generic_readlink(dentry, buffer, buflen);
+ link = inode->i_link;
+ if (!link) {
+ link = inode->i_op->get_link(dentry, inode, &done);
+ if (IS_ERR(link))
+ return PTR_ERR(link);
+ }
+ res = readlink_copy(buffer, buflen, link);
+ do_delayed_call(&done);
+ return res;
}
EXPORT_SYMBOL(vfs_readlink);
projects / linux-2.6-microblaze.git / blobdiff