/*
FUSE: Filesystem in Userspace
- Copyright (C) 2001-2006 Miklos Szeredi <miklos@szeredi.hu>
+ Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
This program can be distributed under the terms of the GNU GPL.
See the file COPYING.
* timeout is unknown (unlink, rmdir, rename and in some cases
* lookup)
*/
-static void fuse_invalidate_entry_cache(struct dentry *entry)
+void fuse_invalidate_entry_cache(struct dentry *entry)
{
fuse_dentry_settime(entry, 0);
}
fuse_invalidate_entry_cache(entry);
}
-static void fuse_lookup_init(struct fuse_req *req, struct inode *dir,
- struct dentry *entry,
+static void fuse_lookup_init(struct fuse_conn *fc, struct fuse_req *req,
+ u64 nodeid, struct qstr *name,
struct fuse_entry_out *outarg)
{
+ memset(outarg, 0, sizeof(struct fuse_entry_out));
req->in.h.opcode = FUSE_LOOKUP;
- req->in.h.nodeid = get_node_id(dir);
+ req->in.h.nodeid = nodeid;
req->in.numargs = 1;
- req->in.args[0].size = entry->d_name.len + 1;
- req->in.args[0].value = entry->d_name.name;
+ req->in.args[0].size = name->len + 1;
+ req->in.args[0].value = name->name;
req->out.numargs = 1;
- req->out.args[0].size = sizeof(struct fuse_entry_out);
+ if (fc->minor < 9)
+ req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
+ else
+ req->out.args[0].size = sizeof(struct fuse_entry_out);
req->out.args[0].value = outarg;
}
+u64 fuse_get_attr_version(struct fuse_conn *fc)
+{
+ u64 curr_version;
+
+ /*
+ * The spin lock isn't actually needed on 64bit archs, but we
+ * don't yet care too much about such optimizations.
+ */
+ spin_lock(&fc->lock);
+ curr_version = fc->attr_version;
+ spin_unlock(&fc->lock);
+
+ return curr_version;
+}
+
/*
* Check whether the dentry is still valid
*
return 0;
}
- spin_lock(&fc->lock);
- attr_version = fc->attr_version;
- spin_unlock(&fc->lock);
+ attr_version = fuse_get_attr_version(fc);
parent = dget_parent(entry);
- fuse_lookup_init(req, parent->d_inode, entry, &outarg);
- request_send(fc, req);
+ fuse_lookup_init(fc, req, get_node_id(parent->d_inode),
+ &entry->d_name, &outarg);
+ fuse_request_send(fc, req);
dput(parent);
err = req->out.h.error;
fuse_put_request(fc, req);
return 0;
}
spin_lock(&fc->lock);
- fi->nlookup ++;
+ fi->nlookup++;
spin_unlock(&fc->lock);
}
fuse_put_request(fc, forget_req);
return !nodeid || nodeid == FUSE_ROOT_ID;
}
-static struct dentry_operations fuse_dentry_operations = {
+const struct dentry_operations fuse_dentry_operations = {
.d_revalidate = fuse_dentry_revalidate,
};
* Add a directory inode to a dentry, ensuring that no other dentry
* refers to this inode. Called with fc->inst_mutex.
*/
-static int fuse_d_add_directory(struct dentry *entry, struct inode *inode)
+static struct dentry *fuse_d_add_directory(struct dentry *entry,
+ struct inode *inode)
{
struct dentry *alias = d_find_alias(inode);
- if (alias) {
+ if (alias && !(alias->d_flags & DCACHE_DISCONNECTED)) {
/* This tries to shrink the subtree below alias */
fuse_invalidate_entry(alias);
dput(alias);
if (!list_empty(&inode->i_dentry))
- return -EBUSY;
+ return ERR_PTR(-EBUSY);
+ } else {
+ dput(alias);
}
- d_add(entry, inode);
- return 0;
+ return d_splice_alias(inode, entry);
}
-static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
- struct nameidata *nd)
+int fuse_lookup_name(struct super_block *sb, u64 nodeid, struct qstr *name,
+ struct fuse_entry_out *outarg, struct inode **inode)
{
- int err;
- struct fuse_entry_out outarg;
- struct inode *inode = NULL;
- struct fuse_conn *fc = get_fuse_conn(dir);
+ struct fuse_conn *fc = get_fuse_conn_super(sb);
struct fuse_req *req;
struct fuse_req *forget_req;
u64 attr_version;
+ int err;
- if (entry->d_name.len > FUSE_NAME_MAX)
- return ERR_PTR(-ENAMETOOLONG);
+ *inode = NULL;
+ err = -ENAMETOOLONG;
+ if (name->len > FUSE_NAME_MAX)
+ goto out;
req = fuse_get_req(fc);
+ err = PTR_ERR(req);
if (IS_ERR(req))
- return ERR_PTR(PTR_ERR(req));
+ goto out;
forget_req = fuse_get_req(fc);
+ err = PTR_ERR(forget_req);
if (IS_ERR(forget_req)) {
fuse_put_request(fc, req);
- return ERR_PTR(PTR_ERR(forget_req));
+ goto out;
}
- spin_lock(&fc->lock);
- attr_version = fc->attr_version;
- spin_unlock(&fc->lock);
+ attr_version = fuse_get_attr_version(fc);
- fuse_lookup_init(req, dir, entry, &outarg);
- request_send(fc, req);
+ fuse_lookup_init(fc, req, nodeid, name, outarg);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
/* Zero nodeid is same as -ENOENT, but with valid timeout */
- if (!err && outarg.nodeid &&
- (invalid_nodeid(outarg.nodeid) ||
- !fuse_valid_type(outarg.attr.mode)))
- err = -EIO;
- if (!err && outarg.nodeid) {
- inode = fuse_iget(dir->i_sb, outarg.nodeid, outarg.generation,
- &outarg.attr, entry_attr_timeout(&outarg),
- attr_version);
- if (!inode) {
- fuse_send_forget(fc, forget_req, outarg.nodeid, 1);
- return ERR_PTR(-ENOMEM);
- }
+ if (err || !outarg->nodeid)
+ goto out_put_forget;
+
+ err = -EIO;
+ if (!outarg->nodeid)
+ goto out_put_forget;
+ if (!fuse_valid_type(outarg->attr.mode))
+ goto out_put_forget;
+
+ *inode = fuse_iget(sb, outarg->nodeid, outarg->generation,
+ &outarg->attr, entry_attr_timeout(outarg),
+ attr_version);
+ err = -ENOMEM;
+ if (!*inode) {
+ fuse_send_forget(fc, forget_req, outarg->nodeid, 1);
+ goto out;
}
+ err = 0;
+
+ out_put_forget:
fuse_put_request(fc, forget_req);
- if (err && err != -ENOENT)
- return ERR_PTR(err);
+ out:
+ return err;
+}
+
+static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
+ struct nameidata *nd)
+{
+ int err;
+ struct fuse_entry_out outarg;
+ struct inode *inode;
+ struct dentry *newent;
+ struct fuse_conn *fc = get_fuse_conn(dir);
+ bool outarg_valid = true;
+
+ err = fuse_lookup_name(dir->i_sb, get_node_id(dir), &entry->d_name,
+ &outarg, &inode);
+ if (err == -ENOENT) {
+ outarg_valid = false;
+ err = 0;
+ }
+ if (err)
+ goto out_err;
+
+ err = -EIO;
+ if (inode && get_node_id(inode) == FUSE_ROOT_ID)
+ goto out_iput;
if (inode && S_ISDIR(inode->i_mode)) {
mutex_lock(&fc->inst_mutex);
- err = fuse_d_add_directory(entry, inode);
+ newent = fuse_d_add_directory(entry, inode);
mutex_unlock(&fc->inst_mutex);
- if (err) {
- iput(inode);
- return ERR_PTR(err);
- }
- } else
- d_add(entry, inode);
+ err = PTR_ERR(newent);
+ if (IS_ERR(newent))
+ goto out_iput;
+ } else {
+ newent = d_splice_alias(inode, entry);
+ }
+ entry = newent ? newent : entry;
entry->d_op = &fuse_dentry_operations;
- if (!err)
+ if (outarg_valid)
fuse_change_entry_timeout(entry, &outarg);
else
fuse_invalidate_entry_cache(entry);
- return NULL;
+
+ return newent;
+
+ out_iput:
+ iput(inode);
+ out_err:
+ return ERR_PTR(err);
}
/*
{
fuse_release_fill(ff, nodeid, flags, FUSE_RELEASE);
ff->reserved_req->force = 1;
- request_send(fc, ff->reserved_req);
+ fuse_request_send(fc, ff->reserved_req);
fuse_put_request(fc, ff->reserved_req);
kfree(ff);
}
goto out_put_forget_req;
err = -ENOMEM;
- ff = fuse_file_alloc();
+ ff = fuse_file_alloc(fc);
if (!ff)
goto out_put_request;
flags &= ~O_NOCTTY;
memset(&inarg, 0, sizeof(inarg));
+ memset(&outentry, 0, sizeof(outentry));
inarg.flags = flags;
inarg.mode = mode;
req->in.h.opcode = FUSE_CREATE;
req->in.args[1].size = entry->d_name.len + 1;
req->in.args[1].value = entry->d_name.name;
req->out.numargs = 2;
- req->out.args[0].size = sizeof(outentry);
+ if (fc->minor < 9)
+ req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
+ else
+ req->out.args[0].size = sizeof(outentry);
req->out.args[0].value = &outentry;
req->out.args[1].size = sizeof(outopen);
req->out.args[1].value = &outopen;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
if (err) {
if (err == -ENOSYS)
fuse_put_request(fc, forget_req);
d_instantiate(entry, inode);
fuse_change_entry_timeout(entry, &outentry);
+ fuse_invalidate_attr(dir);
file = lookup_instantiate_filp(nd, entry, generic_file_open);
if (IS_ERR(file)) {
ff->fh = outopen.fh;
return PTR_ERR(forget_req);
}
+ memset(&outarg, 0, sizeof(outarg));
req->in.h.nodeid = get_node_id(dir);
req->out.numargs = 1;
- req->out.args[0].size = sizeof(outarg);
+ if (fc->minor < 9)
+ req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
+ else
+ req->out.args[0].size = sizeof(outarg);
req->out.args[0].value = &outarg;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (err)
req->in.numargs = 1;
req->in.args[0].size = entry->d_name.len + 1;
req->in.args[0].value = entry->d_name.name;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (!err) {
struct inode *inode = entry->d_inode;
- /* Set nlink to zero so the inode can be cleared, if
- the inode does have more links this will be
- discovered at the next lookup/getattr */
+ /*
+ * Set nlink to zero so the inode can be cleared, if the inode
+ * does have more links this will be discovered at the next
+ * lookup/getattr.
+ */
clear_nlink(inode);
fuse_invalidate_attr(inode);
fuse_invalidate_attr(dir);
req->in.numargs = 1;
req->in.args[0].size = entry->d_name.len + 1;
req->in.args[0].value = entry->d_name.name;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (!err) {
req->in.args[1].value = oldent->d_name.name;
req->in.args[2].size = newent->d_name.len + 1;
req->in.args[2].value = newent->d_name.name;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (!err) {
+ /* ctime changes */
+ fuse_invalidate_attr(oldent->d_inode);
+
fuse_invalidate_attr(olddir);
if (olddir != newdir)
fuse_invalidate_attr(newdir);
if (IS_ERR(req))
return PTR_ERR(req);
- spin_lock(&fc->lock);
- attr_version = fc->attr_version;
- spin_unlock(&fc->lock);
+ attr_version = fuse_get_attr_version(fc);
memset(&inarg, 0, sizeof(inarg));
+ memset(&outarg, 0, sizeof(outarg));
/* Directories have separate file-handle space */
if (file && S_ISREG(inode->i_mode)) {
struct fuse_file *ff = file->private_data;
req->in.args[0].size = sizeof(inarg);
req->in.args[0].value = &inarg;
req->out.numargs = 1;
- req->out.args[0].size = sizeof(outarg);
+ if (fc->minor < 9)
+ req->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE;
+ else
+ req->out.args[0].size = sizeof(outarg);
req->out.args[0].value = &outarg;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (!err) {
return err;
}
+int fuse_update_attributes(struct inode *inode, struct kstat *stat,
+ struct file *file, bool *refreshed)
+{
+ struct fuse_inode *fi = get_fuse_inode(inode);
+ int err;
+ bool r;
+
+ if (fi->i_time < get_jiffies_64()) {
+ r = true;
+ err = fuse_do_getattr(inode, stat, file);
+ } else {
+ r = false;
+ err = 0;
+ if (stat) {
+ generic_fillattr(inode, stat);
+ stat->mode = fi->orig_i_mode;
+ }
+ }
+
+ if (refreshed != NULL)
+ *refreshed = r;
+
+ return err;
+}
+
/*
* Calling into a user-controlled filesystem gives the filesystem
* daemon ptrace-like capabilities over the requester process. This
*/
int fuse_allow_task(struct fuse_conn *fc, struct task_struct *task)
{
+ const struct cred *cred;
+ int ret;
+
if (fc->flags & FUSE_ALLOW_OTHER)
return 1;
- if (task->euid == fc->user_id &&
- task->suid == fc->user_id &&
- task->uid == fc->user_id &&
- task->egid == fc->group_id &&
- task->sgid == fc->group_id &&
- task->gid == fc->group_id)
- return 1;
+ rcu_read_lock();
+ ret = 0;
+ cred = __task_cred(task);
+ if (cred->euid == fc->user_id &&
+ cred->suid == fc->user_id &&
+ cred->uid == fc->user_id &&
+ cred->egid == fc->group_id &&
+ cred->sgid == fc->group_id &&
+ cred->gid == fc->group_id)
+ ret = 1;
+ rcu_read_unlock();
- return 0;
+ return ret;
}
static int fuse_access(struct inode *inode, int mask)
return PTR_ERR(req);
memset(&inarg, 0, sizeof(inarg));
- inarg.mask = mask;
+ inarg.mask = mask & (MAY_READ | MAY_WRITE | MAY_EXEC);
req->in.h.opcode = FUSE_ACCESS;
req->in.h.nodeid = get_node_id(inode);
req->in.numargs = 1;
req->in.args[0].size = sizeof(inarg);
req->in.args[0].value = &inarg;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (err == -ENOSYS) {
* access request is sent. Execute permission is still checked
* locally based on file mode.
*/
-static int fuse_permission(struct inode *inode, int mask, struct nameidata *nd)
+static int fuse_permission(struct inode *inode, int mask)
{
struct fuse_conn *fc = get_fuse_conn(inode);
bool refreshed = false;
*/
if ((fc->flags & FUSE_DEFAULT_PERMISSIONS) ||
((mask & MAY_EXEC) && S_ISREG(inode->i_mode))) {
- struct fuse_inode *fi = get_fuse_inode(inode);
- if (fi->i_time < get_jiffies_64()) {
- err = fuse_do_getattr(inode, NULL, NULL);
- if (err)
- return err;
-
- refreshed = true;
- }
+ err = fuse_update_attributes(inode, NULL, NULL, &refreshed);
+ if (err)
+ return err;
}
if (fc->flags & FUSE_DEFAULT_PERMISSIONS) {
- int err = generic_permission(inode, mask, NULL);
+ err = generic_permission(inode, mask, NULL);
/* If permission is denied, try to refresh file
attributes. This is also needed, because the root
exist. So if permissions are revoked this won't be
noticed immediately, only after the attribute
timeout has expired */
- } else if (nd && (nd->flags & (LOOKUP_ACCESS | LOOKUP_CHDIR))) {
+ } else if (mask & MAY_ACCESS) {
err = fuse_access(inode, mask);
} else if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode)) {
if (!(inode->i_mode & S_IXUGO)) {
struct page *page;
struct inode *inode = file->f_path.dentry->d_inode;
struct fuse_conn *fc = get_fuse_conn(inode);
- struct fuse_file *ff = file->private_data;
struct fuse_req *req;
if (is_bad_inode(inode))
fuse_put_request(fc, req);
return -ENOMEM;
}
+ req->out.argpages = 1;
req->num_pages = 1;
req->pages[0] = page;
- fuse_read_fill(req, ff, inode, file->f_pos, PAGE_SIZE, FUSE_READDIR);
- request_send(fc, req);
+ fuse_read_fill(req, file, inode, file->f_pos, PAGE_SIZE, FUSE_READDIR);
+ fuse_request_send(fc, req);
nbytes = req->out.args[0].size;
err = req->out.h.error;
fuse_put_request(fc, req);
char *link;
if (IS_ERR(req))
- return ERR_PTR(PTR_ERR(req));
+ return ERR_CAST(req);
link = (char *) __get_free_page(GFP_KERNEL);
if (!link) {
req->out.numargs = 1;
req->out.args[0].size = PAGE_SIZE - 1;
req->out.args[0].value = link;
- request_send(fc, req);
+ fuse_request_send(fc, req);
if (req->out.h.error) {
free_page((unsigned long) link);
link = ERR_PTR(req->out.h.error);
}
/*
+ * Prevent concurrent writepages on inode
+ *
+ * This is done by adding a negative bias to the inode write counter
+ * and waiting for all pending writes to finish.
+ */
+void fuse_set_nowrite(struct inode *inode)
+{
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+
+ BUG_ON(!mutex_is_locked(&inode->i_mutex));
+
+ spin_lock(&fc->lock);
+ BUG_ON(fi->writectr < 0);
+ fi->writectr += FUSE_NOWRITE;
+ spin_unlock(&fc->lock);
+ wait_event(fi->page_waitq, fi->writectr == FUSE_NOWRITE);
+}
+
+/*
+ * Allow writepages on inode
+ *
+ * Remove the bias from the writecounter and send any queued
+ * writepages.
+ */
+static void __fuse_release_nowrite(struct inode *inode)
+{
+ struct fuse_inode *fi = get_fuse_inode(inode);
+
+ BUG_ON(fi->writectr != FUSE_NOWRITE);
+ fi->writectr = 0;
+ fuse_flush_writepages(inode);
+}
+
+void fuse_release_nowrite(struct inode *inode)
+{
+ struct fuse_conn *fc = get_fuse_conn(inode);
+
+ spin_lock(&fc->lock);
+ __fuse_release_nowrite(inode);
+ spin_unlock(&fc->lock);
+}
+
+/*
* Set attributes, and at the same time refresh them.
*
* Truncation is slightly complicated, because the 'truncate' request
struct fuse_req *req;
struct fuse_setattr_in inarg;
struct fuse_attr_out outarg;
+ bool is_truncate = false;
+ loff_t oldsize;
int err;
if (!fuse_allow_task(fc, current))
send_sig(SIGXFSZ, current, 0);
return -EFBIG;
}
+ is_truncate = true;
}
req = fuse_get_req(fc);
if (IS_ERR(req))
return PTR_ERR(req);
+ if (is_truncate)
+ fuse_set_nowrite(inode);
+
memset(&inarg, 0, sizeof(inarg));
+ memset(&outarg, 0, sizeof(outarg));
iattr_to_fattr(attr, &inarg);
if (file) {
struct fuse_file *ff = file->private_data;
req->in.args[0].size = sizeof(inarg);
req->in.args[0].value = &inarg;
req->out.numargs = 1;
- req->out.args[0].size = sizeof(outarg);
+ if (fc->minor < 9)
+ req->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE;
+ else
+ req->out.args[0].size = sizeof(outarg);
req->out.args[0].value = &outarg;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (err) {
if (err == -EINTR)
fuse_invalidate_attr(inode);
- return err;
+ goto error;
}
if ((inode->i_mode ^ outarg.attr.mode) & S_IFMT) {
make_bad_inode(inode);
- return -EIO;
+ err = -EIO;
+ goto error;
+ }
+
+ spin_lock(&fc->lock);
+ fuse_change_attributes_common(inode, &outarg.attr,
+ attr_timeout(&outarg));
+ oldsize = inode->i_size;
+ i_size_write(inode, outarg.attr.size);
+
+ if (is_truncate) {
+ /* NOTE: this may release/reacquire fc->lock */
+ __fuse_release_nowrite(inode);
+ }
+ spin_unlock(&fc->lock);
+
+ /*
+ * Only call invalidate_inode_pages2() after removing
+ * FUSE_NOWRITE, otherwise fuse_launder_page() would deadlock.
+ */
+ if (S_ISREG(inode->i_mode) && oldsize != outarg.attr.size) {
+ if (outarg.attr.size < oldsize)
+ fuse_truncate(inode->i_mapping, outarg.attr.size);
+ invalidate_inode_pages2(inode->i_mapping);
}
- fuse_change_attributes(inode, &outarg.attr, attr_timeout(&outarg), 0);
return 0;
+
+error:
+ if (is_truncate)
+ fuse_release_nowrite(inode);
+
+ return err;
}
static int fuse_setattr(struct dentry *entry, struct iattr *attr)
struct kstat *stat)
{
struct inode *inode = entry->d_inode;
- struct fuse_inode *fi = get_fuse_inode(inode);
struct fuse_conn *fc = get_fuse_conn(inode);
- int err;
if (!fuse_allow_task(fc, current))
return -EACCES;
- if (fi->i_time < get_jiffies_64())
- err = fuse_do_getattr(inode, stat, NULL);
- else {
- err = 0;
- generic_fillattr(inode, stat);
- stat->mode = fi->orig_i_mode;
- }
-
- return err;
+ return fuse_update_attributes(inode, stat, NULL, NULL);
}
static int fuse_setxattr(struct dentry *entry, const char *name,
req->in.args[1].value = name;
req->in.args[2].size = size;
req->in.args[2].value = value;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (err == -ENOSYS) {
req->out.args[0].size = sizeof(outarg);
req->out.args[0].value = &outarg;
}
- request_send(fc, req);
+ fuse_request_send(fc, req);
ret = req->out.h.error;
if (!ret)
ret = size ? req->out.args[0].size : outarg.size;
req->out.args[0].size = sizeof(outarg);
req->out.args[0].value = &outarg;
}
- request_send(fc, req);
+ fuse_request_send(fc, req);
ret = req->out.h.error;
if (!ret)
ret = size ? req->out.args[0].size : outarg.size;
req->in.numargs = 1;
req->in.args[0].size = strlen(name) + 1;
req->in.args[0].value = name;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (err == -ENOSYS) {