fuse: Use generic xattr ops

In preparation for posix acl support, rework fuse to use xattr handlers and
the generic setxattr/getxattr/listxattr callbacks.  Split the xattr code
out into it's own file, and promote symbols to module-global scope as
needed.

Functionally these changes have no impact, as fuse still uses a single
handler for all xattrs which uses the old callbacks.

Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This commit is contained in:
Seth Forshee 2016-08-29 08:46:36 -05:00 committed by Miklos Szeredi
parent cb3ae6d25a
commit 703c73629f
5 changed files with 221 additions and 176 deletions

View file

@ -5,4 +5,4 @@
obj-$(CONFIG_FUSE_FS) += fuse.o
obj-$(CONFIG_CUSE) += cuse.o
fuse-objs := dev.o dir.o file.o inode.o control.o
fuse-objs := dev.o dir.o file.o inode.o control.o xattr.o

View file

@ -13,6 +13,7 @@
#include <linux/sched.h>
#include <linux/namei.h>
#include <linux/slab.h>
#include <linux/xattr.h>
static bool fuse_use_readdirplus(struct inode *dir, struct dir_context *ctx)
{
@ -634,7 +635,7 @@ static int fuse_symlink(struct inode *dir, struct dentry *entry,
return create_new_entry(fc, &args, dir, entry, S_IFLNK);
}
static inline void fuse_update_ctime(struct inode *inode)
void fuse_update_ctime(struct inode *inode)
{
if (!IS_NOCMTIME(inode)) {
inode->i_ctime = current_fs_time(inode->i_sb);
@ -1724,171 +1725,6 @@ static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry,
return fuse_update_attributes(inode, stat, NULL, NULL);
}
static int fuse_setxattr(struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
{
struct fuse_conn *fc = get_fuse_conn(inode);
FUSE_ARGS(args);
struct fuse_setxattr_in inarg;
int err;
if (fc->no_setxattr)
return -EOPNOTSUPP;
memset(&inarg, 0, sizeof(inarg));
inarg.size = size;
inarg.flags = flags;
args.in.h.opcode = FUSE_SETXATTR;
args.in.h.nodeid = get_node_id(inode);
args.in.numargs = 3;
args.in.args[0].size = sizeof(inarg);
args.in.args[0].value = &inarg;
args.in.args[1].size = strlen(name) + 1;
args.in.args[1].value = name;
args.in.args[2].size = size;
args.in.args[2].value = value;
err = fuse_simple_request(fc, &args);
if (err == -ENOSYS) {
fc->no_setxattr = 1;
err = -EOPNOTSUPP;
}
if (!err) {
fuse_invalidate_attr(inode);
fuse_update_ctime(inode);
}
return err;
}
static ssize_t fuse_getxattr(struct dentry *entry, struct inode *inode,
const char *name, void *value, size_t size)
{
struct fuse_conn *fc = get_fuse_conn(inode);
FUSE_ARGS(args);
struct fuse_getxattr_in inarg;
struct fuse_getxattr_out outarg;
ssize_t ret;
if (fc->no_getxattr)
return -EOPNOTSUPP;
memset(&inarg, 0, sizeof(inarg));
inarg.size = size;
args.in.h.opcode = FUSE_GETXATTR;
args.in.h.nodeid = get_node_id(inode);
args.in.numargs = 2;
args.in.args[0].size = sizeof(inarg);
args.in.args[0].value = &inarg;
args.in.args[1].size = strlen(name) + 1;
args.in.args[1].value = name;
/* This is really two different operations rolled into one */
args.out.numargs = 1;
if (size) {
args.out.argvar = 1;
args.out.args[0].size = size;
args.out.args[0].value = value;
} else {
args.out.args[0].size = sizeof(outarg);
args.out.args[0].value = &outarg;
}
ret = fuse_simple_request(fc, &args);
if (!ret && !size)
ret = outarg.size;
if (ret == -ENOSYS) {
fc->no_getxattr = 1;
ret = -EOPNOTSUPP;
}
return ret;
}
static int fuse_verify_xattr_list(char *list, size_t size)
{
size_t origsize = size;
while (size) {
size_t thislen = strnlen(list, size);
if (!thislen || thislen == size)
return -EIO;
size -= thislen + 1;
list += thislen + 1;
}
return origsize;
}
static ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size)
{
struct inode *inode = d_inode(entry);
struct fuse_conn *fc = get_fuse_conn(inode);
FUSE_ARGS(args);
struct fuse_getxattr_in inarg;
struct fuse_getxattr_out outarg;
ssize_t ret;
if (!fuse_allow_current_process(fc))
return -EACCES;
if (fc->no_listxattr)
return -EOPNOTSUPP;
memset(&inarg, 0, sizeof(inarg));
inarg.size = size;
args.in.h.opcode = FUSE_LISTXATTR;
args.in.h.nodeid = get_node_id(inode);
args.in.numargs = 1;
args.in.args[0].size = sizeof(inarg);
args.in.args[0].value = &inarg;
/* This is really two different operations rolled into one */
args.out.numargs = 1;
if (size) {
args.out.argvar = 1;
args.out.args[0].size = size;
args.out.args[0].value = list;
} else {
args.out.args[0].size = sizeof(outarg);
args.out.args[0].value = &outarg;
}
ret = fuse_simple_request(fc, &args);
if (!ret && !size)
ret = outarg.size;
if (ret > 0 && size)
ret = fuse_verify_xattr_list(list, ret);
if (ret == -ENOSYS) {
fc->no_listxattr = 1;
ret = -EOPNOTSUPP;
}
return ret;
}
static int fuse_removexattr(struct dentry *entry, const char *name)
{
struct inode *inode = d_inode(entry);
struct fuse_conn *fc = get_fuse_conn(inode);
FUSE_ARGS(args);
int err;
if (fc->no_removexattr)
return -EOPNOTSUPP;
args.in.h.opcode = FUSE_REMOVEXATTR;
args.in.h.nodeid = get_node_id(inode);
args.in.numargs = 1;
args.in.args[0].size = strlen(name) + 1;
args.in.args[0].value = name;
err = fuse_simple_request(fc, &args);
if (err == -ENOSYS) {
fc->no_removexattr = 1;
err = -EOPNOTSUPP;
}
if (!err) {
fuse_invalidate_attr(inode);
fuse_update_ctime(inode);
}
return err;
}
static const struct inode_operations fuse_dir_inode_operations = {
.lookup = fuse_lookup,
.mkdir = fuse_mkdir,
@ -1903,10 +1739,10 @@ static const struct inode_operations fuse_dir_inode_operations = {
.mknod = fuse_mknod,
.permission = fuse_permission,
.getattr = fuse_getattr,
.setxattr = fuse_setxattr,
.getxattr = fuse_getxattr,
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
.listxattr = fuse_listxattr,
.removexattr = fuse_removexattr,
.removexattr = generic_removexattr,
};
static const struct file_operations fuse_dir_operations = {
@ -1924,10 +1760,10 @@ static const struct inode_operations fuse_common_inode_operations = {
.setattr = fuse_setattr,
.permission = fuse_permission,
.getattr = fuse_getattr,
.setxattr = fuse_setxattr,
.getxattr = fuse_getxattr,
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
.listxattr = fuse_listxattr,
.removexattr = fuse_removexattr,
.removexattr = generic_removexattr,
};
static const struct inode_operations fuse_symlink_inode_operations = {
@ -1935,10 +1771,10 @@ static const struct inode_operations fuse_symlink_inode_operations = {
.get_link = fuse_get_link,
.readlink = generic_readlink,
.getattr = fuse_getattr,
.setxattr = fuse_setxattr,
.getxattr = fuse_getxattr,
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
.listxattr = fuse_listxattr,
.removexattr = fuse_removexattr,
.removexattr = generic_removexattr,
};
void fuse_init_common(struct inode *inode)

View file

@ -902,6 +902,8 @@ int fuse_allow_current_process(struct fuse_conn *fc);
u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);
void fuse_update_ctime(struct inode *inode);
int fuse_update_attributes(struct inode *inode, struct kstat *stat,
struct file *file, bool *refreshed);
@ -966,4 +968,7 @@ void fuse_set_initialized(struct fuse_conn *fc);
void fuse_unlock_inode(struct inode *inode);
void fuse_lock_inode(struct inode *inode);
ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size);
extern const struct xattr_handler *fuse_xattr_handlers[];
#endif /* _FS_FUSE_I_H */

View file

@ -1071,6 +1071,7 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
}
sb->s_magic = FUSE_SUPER_MAGIC;
sb->s_op = &fuse_super_operations;
sb->s_xattr = fuse_xattr_handlers;
sb->s_maxbytes = MAX_LFS_FILESIZE;
sb->s_time_gran = 1;
sb->s_export_op = &fuse_export_operations;

203
fs/fuse/xattr.c Normal file
View file

@ -0,0 +1,203 @@
/*
* FUSE: Filesystem in Userspace
* Copyright (C) 2001-2016 Miklos Szeredi <miklos@szeredi.hu>
*
* This program can be distributed under the terms of the GNU GPL.
* See the file COPYING.
*/
#include "fuse_i.h"
#include <linux/xattr.h>
static int fuse_setxattr(struct inode *inode, const char *name,
const void *value, size_t size, int flags)
{
struct fuse_conn *fc = get_fuse_conn(inode);
FUSE_ARGS(args);
struct fuse_setxattr_in inarg;
int err;
if (fc->no_setxattr)
return -EOPNOTSUPP;
memset(&inarg, 0, sizeof(inarg));
inarg.size = size;
inarg.flags = flags;
args.in.h.opcode = FUSE_SETXATTR;
args.in.h.nodeid = get_node_id(inode);
args.in.numargs = 3;
args.in.args[0].size = sizeof(inarg);
args.in.args[0].value = &inarg;
args.in.args[1].size = strlen(name) + 1;
args.in.args[1].value = name;
args.in.args[2].size = size;
args.in.args[2].value = value;
err = fuse_simple_request(fc, &args);
if (err == -ENOSYS) {
fc->no_setxattr = 1;
err = -EOPNOTSUPP;
}
if (!err) {
fuse_invalidate_attr(inode);
fuse_update_ctime(inode);
}
return err;
}
static ssize_t fuse_getxattr(struct inode *inode, const char *name,
void *value, size_t size)
{
struct fuse_conn *fc = get_fuse_conn(inode);
FUSE_ARGS(args);
struct fuse_getxattr_in inarg;
struct fuse_getxattr_out outarg;
ssize_t ret;
if (fc->no_getxattr)
return -EOPNOTSUPP;
memset(&inarg, 0, sizeof(inarg));
inarg.size = size;
args.in.h.opcode = FUSE_GETXATTR;
args.in.h.nodeid = get_node_id(inode);
args.in.numargs = 2;
args.in.args[0].size = sizeof(inarg);
args.in.args[0].value = &inarg;
args.in.args[1].size = strlen(name) + 1;
args.in.args[1].value = name;
/* This is really two different operations rolled into one */
args.out.numargs = 1;
if (size) {
args.out.argvar = 1;
args.out.args[0].size = size;
args.out.args[0].value = value;
} else {
args.out.args[0].size = sizeof(outarg);
args.out.args[0].value = &outarg;
}
ret = fuse_simple_request(fc, &args);
if (!ret && !size)
ret = outarg.size;
if (ret == -ENOSYS) {
fc->no_getxattr = 1;
ret = -EOPNOTSUPP;
}
return ret;
}
static int fuse_verify_xattr_list(char *list, size_t size)
{
size_t origsize = size;
while (size) {
size_t thislen = strnlen(list, size);
if (!thislen || thislen == size)
return -EIO;
size -= thislen + 1;
list += thislen + 1;
}
return origsize;
}
ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size)
{
struct inode *inode = d_inode(entry);
struct fuse_conn *fc = get_fuse_conn(inode);
FUSE_ARGS(args);
struct fuse_getxattr_in inarg;
struct fuse_getxattr_out outarg;
ssize_t ret;
if (!fuse_allow_current_process(fc))
return -EACCES;
if (fc->no_listxattr)
return -EOPNOTSUPP;
memset(&inarg, 0, sizeof(inarg));
inarg.size = size;
args.in.h.opcode = FUSE_LISTXATTR;
args.in.h.nodeid = get_node_id(inode);
args.in.numargs = 1;
args.in.args[0].size = sizeof(inarg);
args.in.args[0].value = &inarg;
/* This is really two different operations rolled into one */
args.out.numargs = 1;
if (size) {
args.out.argvar = 1;
args.out.args[0].size = size;
args.out.args[0].value = list;
} else {
args.out.args[0].size = sizeof(outarg);
args.out.args[0].value = &outarg;
}
ret = fuse_simple_request(fc, &args);
if (!ret && !size)
ret = outarg.size;
if (ret > 0 && size)
ret = fuse_verify_xattr_list(list, ret);
if (ret == -ENOSYS) {
fc->no_listxattr = 1;
ret = -EOPNOTSUPP;
}
return ret;
}
static int fuse_removexattr(struct inode *inode, const char *name)
{
struct fuse_conn *fc = get_fuse_conn(inode);
FUSE_ARGS(args);
int err;
if (fc->no_removexattr)
return -EOPNOTSUPP;
args.in.h.opcode = FUSE_REMOVEXATTR;
args.in.h.nodeid = get_node_id(inode);
args.in.numargs = 1;
args.in.args[0].size = strlen(name) + 1;
args.in.args[0].value = name;
err = fuse_simple_request(fc, &args);
if (err == -ENOSYS) {
fc->no_removexattr = 1;
err = -EOPNOTSUPP;
}
if (!err) {
fuse_invalidate_attr(inode);
fuse_update_ctime(inode);
}
return err;
}
static int fuse_xattr_get(const struct xattr_handler *handler,
struct dentry *dentry, struct inode *inode,
const char *name, void *value, size_t size)
{
return fuse_getxattr(inode, name, value, size);
}
static int fuse_xattr_set(const struct xattr_handler *handler,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value, size_t size,
int flags)
{
if (!value)
return fuse_removexattr(inode, name);
return fuse_setxattr(inode, name, value, size, flags);
}
static const struct xattr_handler fuse_xattr_handler = {
.prefix = "",
.get = fuse_xattr_get,
.set = fuse_xattr_set,
};
const struct xattr_handler *fuse_xattr_handlers[] = {
&fuse_xattr_handler,
NULL
};