korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-04 17:44:14 +08:00
Code Issues Packages Projects Releases Wiki Activity
64b4cdf22f
linux/fs/orangefs/namei.c
Christian Brauner cac2f8b8d8
fs: rename current get acl method 
The current way of setting and getting posix acls through the generic
xattr interface is error prone and type unsafe. The vfs needs to
interpret and fixup posix acls before storing or reporting it to
userspace. Various hacks exist to make this work. The code is hard to
understand and difficult to maintain in it's current form. Instead of
making this work by hacking posix acls through xattr handlers we are
building a dedicated posix acl api around the get and set inode
operations. This removes a lot of hackiness and makes the codepaths
easier to maintain. A lot of background can be found in [1].

The current inode operation for getting posix acls takes an inode
argument but various filesystems (e.g., 9p, cifs, overlayfs) need access
to the dentry. In contrast to the ->set_acl() inode operation we cannot
simply extend ->get_acl() to take a dentry argument. The ->get_acl()
inode operation is called from:

acl_permission_check()
-> check_acl()
   -> get_acl()

which is part of generic_permission() which in turn is part of
inode_permission(). Both generic_permission() and inode_permission() are
called in the ->permission() handler of various filesystems (e.g.,
overlayfs). So simply passing a dentry argument to ->get_acl() would
amount to also having to pass a dentry argument to ->permission(). We
should avoid this unnecessary change.

So instead of extending the existing inode operation rename it from
->get_acl() to ->get_inode_acl() and add a ->get_acl() method later that
passes a dentry argument and which filesystems that need access to the
dentry can implement instead of ->get_inode_acl(). Filesystems like cifs
which allow setting and getting posix acls but not using them for
permission checking during lookup can simply not implement
->get_inode_acl().

This is intended to be a non-functional change.

Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1]
Suggested-by/Inspired-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-20 10:13:27 +02:00

447 lines
12 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0
/*
* (C) 2001 Clemson University and The University of Chicago
*
* See COPYING in top-level directory.
*/
/*
* Linux VFS namei operations.
*/
#include "protocol.h"
#include "orangefs-kernel.h"
/*
* Get a newly allocated inode to go with a negative dentry.
*/
static int orangefs_create(struct user_namespace *mnt_userns,
struct inode *dir,
struct dentry *dentry,
umode_t mode,
bool exclusive)
{
struct orangefs_inode_s *parent = ORANGEFS_I(dir);
struct orangefs_kernel_op_s *new_op;
struct orangefs_object_kref ref;
struct inode *inode;
struct iattr iattr;
int ret;
gossip_debug(GOSSIP_NAME_DEBUG, "%s: %pd\n",
__func__,
dentry);
new_op = op_alloc(ORANGEFS_VFS_OP_CREATE);
if (!new_op)
return -ENOMEM;
new_op->upcall.req.create.parent_refn = parent->refn;
fill_default_sys_attrs(new_op->upcall.req.create.attributes,
ORANGEFS_TYPE_METAFILE, mode);
strncpy(new_op->upcall.req.create.d_name,
dentry->d_name.name, ORANGEFS_NAME_MAX - 1);
ret = service_operation(new_op, __func__, get_interruptible_flag(dir));
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: %pd: handle:%pU: fsid:%d: new_op:%p: ret:%d:\n",
__func__,
dentry,
&new_op->downcall.resp.create.refn.khandle,
new_op->downcall.resp.create.refn.fs_id,
new_op,
ret);
if (ret < 0)
goto out;
ref = new_op->downcall.resp.create.refn;
inode = orangefs_new_inode(dir->i_sb, dir, S_IFREG | mode, 0, &ref);
if (IS_ERR(inode)) {
gossip_err("%s: Failed to allocate inode for file :%pd:\n",
__func__,
dentry);
ret = PTR_ERR(inode);
goto out;
}
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: Assigned inode :%pU: for file :%pd:\n",
__func__,
get_khandle_from_ino(inode),
dentry);
d_instantiate_new(dentry, inode);
orangefs_set_timeout(dentry);
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: dentry instantiated for %pd\n",
__func__,
dentry);
memset(&iattr, 0, sizeof iattr);
iattr.ia_valid |= ATTR_MTIME | ATTR_CTIME;
iattr.ia_mtime = iattr.ia_ctime = current_time(dir);
__orangefs_setattr(dir, &iattr);
ret = 0;
out:
op_release(new_op);
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: %pd: returning %d\n",
__func__,
dentry,
ret);
return ret;
}
/*
* Attempt to resolve an object name (dentry->d_name), parent handle, and
* fsid into a handle for the object.
*/
static struct dentry *orangefs_lookup(struct inode *dir, struct dentry *dentry,
unsigned int flags)
{
struct orangefs_inode_s *parent = ORANGEFS_I(dir);
struct orangefs_kernel_op_s *new_op;
struct inode *inode;
int ret = -EINVAL;
/*
* in theory we could skip a lookup here (if the intent is to
* create) in order to avoid a potentially failed lookup, but
* leaving it in can skip a valid lookup and try to create a file
* that already exists (e.g. the vfs already handles checking for
* -EEXIST on O_EXCL opens, which is broken if we skip this lookup
* in the create path)
*/
gossip_debug(GOSSIP_NAME_DEBUG, "%s called on %pd\n",
__func__, dentry);
if (dentry->d_name.len > (ORANGEFS_NAME_MAX - 1))
return ERR_PTR(-ENAMETOOLONG);
new_op = op_alloc(ORANGEFS_VFS_OP_LOOKUP);
if (!new_op)
return ERR_PTR(-ENOMEM);
new_op->upcall.req.lookup.sym_follow = ORANGEFS_LOOKUP_LINK_NO_FOLLOW;
gossip_debug(GOSSIP_NAME_DEBUG, "%s:%s:%d using parent %pU\n",
__FILE__,
__func__,
__LINE__,
&parent->refn.khandle);
new_op->upcall.req.lookup.parent_refn = parent->refn;
strncpy(new_op->upcall.req.lookup.d_name, dentry->d_name.name,
ORANGEFS_NAME_MAX - 1);
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: doing lookup on %s under %pU,%d\n",
__func__,
new_op->upcall.req.lookup.d_name,
&new_op->upcall.req.lookup.parent_refn.khandle,
new_op->upcall.req.lookup.parent_refn.fs_id);
ret = service_operation(new_op, __func__, get_interruptible_flag(dir));
gossip_debug(GOSSIP_NAME_DEBUG,
"Lookup Got %pU, fsid %d (ret=%d)\n",
&new_op->downcall.resp.lookup.refn.khandle,
new_op->downcall.resp.lookup.refn.fs_id,
ret);
if (ret == 0) {
orangefs_set_timeout(dentry);
inode = orangefs_iget(dir->i_sb, &new_op->downcall.resp.lookup.refn);
} else if (ret == -ENOENT) {
inode = NULL;
} else {
/* must be a non-recoverable error */
inode = ERR_PTR(ret);
}
op_release(new_op);
return d_splice_alias(inode, dentry);
}
/* return 0 on success; non-zero otherwise */
static int orangefs_unlink(struct inode *dir, struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
struct orangefs_inode_s *parent = ORANGEFS_I(dir);
struct orangefs_kernel_op_s *new_op;
struct iattr iattr;
int ret;
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: called on %pd\n"
" (inode %pU): Parent is %pU | fs_id %d\n",
__func__,
dentry,
get_khandle_from_ino(inode),
&parent->refn.khandle,
parent->refn.fs_id);
new_op = op_alloc(ORANGEFS_VFS_OP_REMOVE);
if (!new_op)
return -ENOMEM;
new_op->upcall.req.remove.parent_refn = parent->refn;
strncpy(new_op->upcall.req.remove.d_name, dentry->d_name.name,
ORANGEFS_NAME_MAX - 1);
ret = service_operation(new_op, "orangefs_unlink",
get_interruptible_flag(inode));
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: service_operation returned:%d:\n",
__func__,
ret);
op_release(new_op);
if (!ret) {
drop_nlink(inode);
memset(&iattr, 0, sizeof iattr);
iattr.ia_valid |= ATTR_MTIME | ATTR_CTIME;
iattr.ia_mtime = iattr.ia_ctime = current_time(dir);
__orangefs_setattr(dir, &iattr);
}
return ret;
}
static int orangefs_symlink(struct user_namespace *mnt_userns,
struct inode *dir,
struct dentry *dentry,
const char *symname)
{
struct orangefs_inode_s *parent = ORANGEFS_I(dir);
struct orangefs_kernel_op_s *new_op;
struct orangefs_object_kref ref;
struct inode *inode;
struct iattr iattr;
int mode = 0755;
int ret;
gossip_debug(GOSSIP_NAME_DEBUG, "%s: called\n", __func__);
if (!symname)
return -EINVAL;
if (strlen(symname)+1 > ORANGEFS_NAME_MAX)
return -ENAMETOOLONG;
new_op = op_alloc(ORANGEFS_VFS_OP_SYMLINK);
if (!new_op)
return -ENOMEM;
new_op->upcall.req.sym.parent_refn = parent->refn;
fill_default_sys_attrs(new_op->upcall.req.sym.attributes,
ORANGEFS_TYPE_SYMLINK,
mode);
strncpy(new_op->upcall.req.sym.entry_name,
dentry->d_name.name,
ORANGEFS_NAME_MAX - 1);
strncpy(new_op->upcall.req.sym.target, symname, ORANGEFS_NAME_MAX - 1);
ret = service_operation(new_op, __func__, get_interruptible_flag(dir));
gossip_debug(GOSSIP_NAME_DEBUG,
"Symlink Got ORANGEFS handle %pU on fsid %d (ret=%d)\n",
&new_op->downcall.resp.sym.refn.khandle,
new_op->downcall.resp.sym.refn.fs_id, ret);
if (ret < 0) {
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: failed with error code %d\n",
__func__, ret);
goto out;
}
ref = new_op->downcall.resp.sym.refn;
inode = orangefs_new_inode(dir->i_sb, dir, S_IFLNK | mode, 0, &ref);
if (IS_ERR(inode)) {
gossip_err
("*** Failed to allocate orangefs symlink inode\n");
ret = PTR_ERR(inode);
goto out;
}
/*
* This is necessary because orangefs_inode_getattr will not
* re-read symlink size as it is impossible for it to change.
* Invalidating the cache does not help. orangefs_new_inode
* does not set the correct size (it does not know symname).
*/
inode->i_size = strlen(symname);
gossip_debug(GOSSIP_NAME_DEBUG,
"Assigned symlink inode new number of %pU\n",
get_khandle_from_ino(inode));
d_instantiate_new(dentry, inode);
orangefs_set_timeout(dentry);
gossip_debug(GOSSIP_NAME_DEBUG,
"Inode (Symlink) %pU -> %pd\n",
get_khandle_from_ino(inode),
dentry);
memset(&iattr, 0, sizeof iattr);
iattr.ia_valid |= ATTR_MTIME | ATTR_CTIME;
iattr.ia_mtime = iattr.ia_ctime = current_time(dir);
__orangefs_setattr(dir, &iattr);
ret = 0;
out:
op_release(new_op);
return ret;
}
static int orangefs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
struct dentry *dentry, umode_t mode)
{
struct orangefs_inode_s *parent = ORANGEFS_I(dir);
struct orangefs_kernel_op_s *new_op;
struct orangefs_object_kref ref;
struct inode *inode;
struct iattr iattr;
int ret;
new_op = op_alloc(ORANGEFS_VFS_OP_MKDIR);
if (!new_op)
return -ENOMEM;
new_op->upcall.req.mkdir.parent_refn = parent->refn;
fill_default_sys_attrs(new_op->upcall.req.mkdir.attributes,
ORANGEFS_TYPE_DIRECTORY, mode);
strncpy(new_op->upcall.req.mkdir.d_name,
dentry->d_name.name, ORANGEFS_NAME_MAX - 1);
ret = service_operation(new_op, __func__, get_interruptible_flag(dir));
gossip_debug(GOSSIP_NAME_DEBUG,
"Mkdir Got ORANGEFS handle %pU on fsid %d\n",
&new_op->downcall.resp.mkdir.refn.khandle,
new_op->downcall.resp.mkdir.refn.fs_id);
if (ret < 0) {
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: failed with error code %d\n",
__func__, ret);
goto out;
}
ref = new_op->downcall.resp.mkdir.refn;
inode = orangefs_new_inode(dir->i_sb, dir, S_IFDIR | mode, 0, &ref);
if (IS_ERR(inode)) {
gossip_err("*** Failed to allocate orangefs dir inode\n");
ret = PTR_ERR(inode);
goto out;
}
gossip_debug(GOSSIP_NAME_DEBUG,
"Assigned dir inode new number of %pU\n",
get_khandle_from_ino(inode));
d_instantiate_new(dentry, inode);
orangefs_set_timeout(dentry);
gossip_debug(GOSSIP_NAME_DEBUG,
"Inode (Directory) %pU -> %pd\n",
get_khandle_from_ino(inode),
dentry);
/*
* NOTE: we have no good way to keep nlink consistent for directories
* across clients; keep constant at 1.
*/
memset(&iattr, 0, sizeof iattr);
iattr.ia_valid |= ATTR_MTIME | ATTR_CTIME;
iattr.ia_mtime = iattr.ia_ctime = current_time(dir);
__orangefs_setattr(dir, &iattr);
out:
op_release(new_op);
return ret;
}
static int orangefs_rename(struct user_namespace *mnt_userns,
struct inode *old_dir,
struct dentry *old_dentry,
struct inode *new_dir,
struct dentry *new_dentry,
unsigned int flags)
{
struct orangefs_kernel_op_s *new_op;
struct iattr iattr;
int ret;
if (flags)
return -EINVAL;
gossip_debug(GOSSIP_NAME_DEBUG,
"orangefs_rename: called (%pd2 => %pd2) ct=%d\n",
old_dentry, new_dentry, d_count(new_dentry));
memset(&iattr, 0, sizeof iattr);
iattr.ia_valid |= ATTR_MTIME | ATTR_CTIME;
iattr.ia_mtime = iattr.ia_ctime = current_time(new_dir);
__orangefs_setattr(new_dir, &iattr);
new_op = op_alloc(ORANGEFS_VFS_OP_RENAME);
if (!new_op)
return -EINVAL;
new_op->upcall.req.rename.old_parent_refn = ORANGEFS_I(old_dir)->refn;
new_op->upcall.req.rename.new_parent_refn = ORANGEFS_I(new_dir)->refn;
strncpy(new_op->upcall.req.rename.d_old_name,
old_dentry->d_name.name,
ORANGEFS_NAME_MAX - 1);
strncpy(new_op->upcall.req.rename.d_new_name,
new_dentry->d_name.name,
ORANGEFS_NAME_MAX - 1);
ret = service_operation(new_op,
"orangefs_rename",
get_interruptible_flag(old_dentry->d_inode));
gossip_debug(GOSSIP_NAME_DEBUG,
"orangefs_rename: got downcall status %d\n",
ret);
if (new_dentry->d_inode)
new_dentry->d_inode->i_ctime = current_time(new_dentry->d_inode);
op_release(new_op);
return ret;
}
/* ORANGEFS implementation of VFS inode operations for directories */
const struct inode_operations orangefs_dir_inode_operations = {
.lookup = orangefs_lookup,
.get_inode_acl = orangefs_get_acl,
.set_acl = orangefs_set_acl,
.create = orangefs_create,
.unlink = orangefs_unlink,
.symlink = orangefs_symlink,
.mkdir = orangefs_mkdir,
.rmdir = orangefs_unlink,
.rename = orangefs_rename,
.setattr = orangefs_setattr,
.getattr = orangefs_getattr,
.listxattr = orangefs_listxattr,
.permission = orangefs_permission,
.update_time = orangefs_update_time,
};
Reference in New Issue View Git Blame Copy Permalink