blob: c5810e97aa2d624f8677f153336f355424cba804 [file] [log] [blame]
/*
FUSE: Filesystem in Userspace
Copyright (C) 2001 Miklos Szeredi (mszeredi@inf.bme.hu)
This program can be distributed under the terms of the GNU GPL.
See the file COPYING.
*/
#include "fuse_i.h"
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/file.h>
static struct inode_operations fuse_dir_inode_operations;
static struct inode_operations fuse_file_inode_operations;
static struct inode_operations fuse_symlink_inode_operations;
static struct file_operations fuse_dir_operations;
static struct dentry_operations fuse_dentry_operations;
/* FIXME: This should be user configurable */
#define FUSE_REVALIDATE_TIME (1 * HZ)
#ifndef KERNEL_2_6
#define new_decode_dev(x) (x)
#define new_encode_dev(x) (x)
#endif
static void change_attributes(struct inode *inode, struct fuse_attr *attr)
{
if(S_ISREG(inode->i_mode) && i_size_read(inode) != attr->size) {
#ifdef KERNEL_2_6
invalidate_inode_pages(inode->i_mapping);
#else
invalidate_inode_pages(inode);
#endif
}
inode->i_mode = (inode->i_mode & S_IFMT) + (attr->mode & 07777);
inode->i_nlink = attr->nlink;
inode->i_uid = attr->uid;
inode->i_gid = attr->gid;
i_size_write(inode, attr->size);
inode->i_blksize = PAGE_CACHE_SIZE;
inode->i_blocks = attr->blocks;
#ifdef KERNEL_2_6
inode->i_atime.tv_sec = attr->atime;
inode->i_atime.tv_nsec = attr->atimensec;
inode->i_mtime.tv_sec = attr->mtime;
inode->i_mtime.tv_nsec = attr->mtimensec;
inode->i_ctime.tv_sec = attr->ctime;
inode->i_ctime.tv_nsec = attr->ctimensec;
#else
inode->i_atime = attr->atime;
inode->i_mtime = attr->mtime;
inode->i_ctime = attr->ctime;
#endif
}
static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
{
inode->i_mode = attr->mode & S_IFMT;
i_size_write(inode, attr->size);
if(S_ISREG(inode->i_mode)) {
inode->i_op = &fuse_file_inode_operations;
fuse_init_file_inode(inode);
}
else if(S_ISDIR(inode->i_mode)) {
inode->i_op = &fuse_dir_inode_operations;
inode->i_fop = &fuse_dir_operations;
}
else if(S_ISLNK(inode->i_mode)) {
inode->i_op = &fuse_symlink_inode_operations;
}
else if(S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)){
inode->i_op = &fuse_file_inode_operations;
init_special_inode(inode, inode->i_mode,
new_decode_dev(attr->rdev));
} else
printk("fuse_init_inode: bad file type: %o\n", inode->i_mode);
inode->u.generic_ip = inode;
}
struct inode *fuse_iget(struct super_block *sb, ino_t ino, int generation,
struct fuse_attr *attr, int version)
{
struct inode *inode;
inode = iget(sb, ino);
if(inode) {
if(!inode->u.generic_ip) {
inode->i_generation = generation;
fuse_init_inode(inode, attr);
} else if(inode->i_generation != generation)
printk("fuse_iget: bad generation for ino %lu\n", ino);
change_attributes(inode, attr);
inode->i_version = version;
}
return inode;
}
static int fuse_do_lookup(struct inode *dir, struct dentry *entry,
struct fuse_lookup_out *outarg, int *version)
{
struct fuse_conn *fc = INO_FC(dir);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_out out = FUSE_OUT_INIT;
in.h.opcode = FUSE_LOOKUP;
in.h.ino = dir->i_ino;
in.numargs = 1;
in.args[0].size = entry->d_name.len + 1;
in.args[0].value = entry->d_name.name;
out.numargs = 1;
out.args[0].size = sizeof(struct fuse_lookup_out);
out.args[0].value = outarg;
request_send(fc, &in, &out);
*version = out.h.unique;
return out.h.error;
}
static int fuse_lookup_iget(struct inode *dir, struct dentry *entry,
struct inode **inodep)
{
int err;
struct fuse_lookup_out outarg;
int version;
struct inode *inode = NULL;
err = fuse_do_lookup(dir, entry, &outarg, &version);
if(!err) {
inode = fuse_iget(dir->i_sb, outarg.ino, outarg.generation,
&outarg.attr, version);
if(!inode)
return -ENOMEM;
} else if(err != -ENOENT)
return err;
entry->d_time = jiffies;
entry->d_op = &fuse_dentry_operations;
*inodep = inode;
return 0;
}
static int lookup_new_entry(struct inode *dir, struct dentry *entry,
struct fuse_lookup_out *outarg, int version,
int mode)
{
struct inode *inode;
inode = fuse_iget(dir->i_sb, outarg->ino, outarg->generation,
&outarg->attr, version);
if(!inode)
return -ENOMEM;
/* Don't allow userspace to do really stupid things... */
if((inode->i_mode ^ mode) & S_IFMT) {
iput(inode);
printk("fuse_mknod: inode has wrong type\n");
return -EINVAL;
}
d_instantiate(entry, inode);
return 0;
}
static int _fuse_mknod(struct inode *dir, struct dentry *entry, int mode,
dev_t rdev)
{
struct fuse_conn *fc = INO_FC(dir);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_out out = FUSE_OUT_INIT;
struct fuse_mknod_in inarg;
struct fuse_lookup_out outarg;
memset(&inarg, 0, sizeof(inarg));
inarg.mode = mode;
inarg.rdev = new_encode_dev(rdev);
in.h.opcode = FUSE_MKNOD;
in.h.ino = dir->i_ino;
in.numargs = 2;
in.args[0].size = sizeof(inarg);
in.args[0].value = &inarg;
in.args[1].size = entry->d_name.len + 1;
in.args[1].value = entry->d_name.name;
out.numargs = 1;
out.args[0].size = sizeof(outarg);
out.args[0].value = &outarg;
request_send(fc, &in, &out);
if(out.h.error)
return out.h.error;
return lookup_new_entry(dir, entry, &outarg, out.h.unique, mode);
}
static int _fuse_create(struct inode *dir, struct dentry *entry, int mode)
{
return _fuse_mknod(dir, entry, mode, 0);
}
static int fuse_mkdir(struct inode *dir, struct dentry *entry, int mode)
{
struct fuse_conn *fc = INO_FC(dir);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_out out = FUSE_OUT_INIT;
struct fuse_mkdir_in inarg;
struct fuse_lookup_out outarg;
memset(&inarg, 0, sizeof(inarg));
inarg.mode = mode;
in.h.opcode = FUSE_MKDIR;
in.h.ino = dir->i_ino;
in.numargs = 2;
in.args[0].size = sizeof(inarg);
in.args[0].value = &inarg;
in.args[1].size = entry->d_name.len + 1;
in.args[1].value = entry->d_name.name;
out.numargs = 1;
out.args[0].size = sizeof(outarg);
out.args[0].value = &outarg;
request_send(fc, &in, &out);
if(out.h.error)
return out.h.error;
return lookup_new_entry(dir, entry, &outarg, out.h.unique, S_IFDIR);
}
static int fuse_symlink(struct inode *dir, struct dentry *entry,
const char *link)
{
struct fuse_conn *fc = INO_FC(dir);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_out out = FUSE_OUT_INIT;
struct fuse_lookup_out outarg;
in.h.opcode = FUSE_SYMLINK;
in.h.ino = dir->i_ino;
in.numargs = 2;
in.args[0].size = entry->d_name.len + 1;
in.args[0].value = entry->d_name.name;
in.args[1].size = strlen(link) + 1;
in.args[1].value = link;
out.numargs = 1;
out.args[0].size = sizeof(outarg);
out.args[0].value = &outarg;
request_send(fc, &in, &out);
if(out.h.error)
return out.h.error;
return lookup_new_entry(dir, entry, &outarg, out.h.unique, S_IFLNK);
}
static int fuse_unlink(struct inode *dir, struct dentry *entry)
{
struct fuse_conn *fc = INO_FC(dir);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_out out = FUSE_OUT_INIT;
in.h.opcode = FUSE_UNLINK;
in.h.ino = dir->i_ino;
in.numargs = 1;
in.args[0].size = entry->d_name.len + 1;
in.args[0].value = entry->d_name.name;
request_send(fc, &in, &out);
if(!out.h.error) {
/* 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 */
/* FIXME: mark inode "not uptodate" */
entry->d_inode->i_nlink = 0;
}
return out.h.error;
}
static int fuse_rmdir(struct inode *dir, struct dentry *entry)
{
struct fuse_conn *fc = INO_FC(dir);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_out out = FUSE_OUT_INIT;
in.h.opcode = FUSE_RMDIR;
in.h.ino = dir->i_ino;
in.numargs = 1;
in.args[0].size = entry->d_name.len + 1;
in.args[0].value = entry->d_name.name;
request_send(fc, &in, &out);
if(!out.h.error)
entry->d_inode->i_nlink = 0;
return out.h.error;
}
static int fuse_rename(struct inode *olddir, struct dentry *oldent,
struct inode *newdir, struct dentry *newent)
{
struct fuse_conn *fc = INO_FC(olddir);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_out out = FUSE_OUT_INIT;
struct fuse_rename_in inarg;
memset(&inarg, 0, sizeof(inarg));
inarg.newdir = newdir->i_ino;
in.h.opcode = FUSE_RENAME;
in.h.ino = olddir->i_ino;
in.numargs = 3;
in.args[0].size = sizeof(inarg);
in.args[0].value = &inarg;
in.args[1].size = oldent->d_name.len + 1;
in.args[1].value = oldent->d_name.name;
in.args[2].size = newent->d_name.len + 1;
in.args[2].value = newent->d_name.name;
request_send(fc, &in, &out);
return out.h.error;
}
static int fuse_link(struct dentry *entry, struct inode *newdir,
struct dentry *newent)
{
struct inode *inode = entry->d_inode;
struct fuse_conn *fc = INO_FC(inode);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_out out = FUSE_OUT_INIT;
struct fuse_link_in inarg;
struct fuse_lookup_out outarg;
memset(&inarg, 0, sizeof(inarg));
inarg.newdir = newdir->i_ino;
in.h.opcode = FUSE_LINK;
in.h.ino = inode->i_ino;
in.numargs = 2;
in.args[0].size = sizeof(inarg);
in.args[0].value = &inarg;
in.args[1].size = newent->d_name.len + 1;
in.args[1].value = newent->d_name.name;
out.numargs = 1;
out.args[0].size = sizeof(outarg);
out.args[0].value = &outarg;
request_send(fc, &in, &out);
if(out.h.error)
return out.h.error;
/* Invalidate old entry, so attributes are refreshed */
d_invalidate(entry);
return lookup_new_entry(newdir, newent, &outarg, out.h.unique,
inode->i_mode);
}
int fuse_do_getattr(struct inode *inode)
{
struct fuse_conn *fc = INO_FC(inode);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_out out = FUSE_OUT_INIT;
struct fuse_getattr_out arg;
in.h.opcode = FUSE_GETATTR;
in.h.ino = inode->i_ino;
out.numargs = 1;
out.args[0].size = sizeof(arg);
out.args[0].value = &arg;
request_send(fc, &in, &out);
if(!out.h.error)
change_attributes(inode, &arg.attr);
return out.h.error;
}
static int fuse_revalidate(struct dentry *entry)
{
struct inode *inode = entry->d_inode;
struct fuse_conn *fc = INO_FC(inode);
if(inode->i_ino == FUSE_ROOT_INO) {
if(!(fc->flags & FUSE_ALLOW_OTHER) &&
current->fsuid != fc->uid)
return -EACCES;
} else if(time_before_eq(jiffies, entry->d_time + FUSE_REVALIDATE_TIME))
return 0;
return fuse_do_getattr(inode);
}
static int _fuse_permission(struct inode *inode, int mask)
{
struct fuse_conn *fc = INO_FC(inode);
if(!(fc->flags & FUSE_ALLOW_OTHER) && current->fsuid != fc->uid)
return -EACCES;
else if(fc->flags & FUSE_DEFAULT_PERMISSIONS) {
int err = vfs_permission(inode, mask);
/* If permission is denied, try to refresh file
attributes. This is also needed, because the root
node will at first have no permissions */
if(err == -EACCES) {
err = fuse_do_getattr(inode);
if(!err)
err = vfs_permission(inode, mask);
}
/* FIXME: Need some mechanism to revoke permissions:
currently if the filesystem suddenly changes the
file mode, we will not be informed abot that, and
continue to allow access to the file/directory.
This is actually not so grave, since the user can
simply keep access to the file/directory anyway by
keeping it open... */
return err;
} else
return 0;
}
static int parse_dirfile(char *buf, size_t nbytes, struct file *file,
void *dstbuf, filldir_t filldir)
{
while(nbytes >= FUSE_NAME_OFFSET) {
struct fuse_dirent *dirent = (struct fuse_dirent *) buf;
size_t reclen = FUSE_DIRENT_SIZE(dirent);
int over;
if(dirent->namelen > NAME_MAX) {
printk("fuse_readdir: name too long\n");
return -EPROTO;
}
if(reclen > nbytes)
break;
over = filldir(dstbuf, dirent->name, dirent->namelen,
file->f_pos, dirent->ino, dirent->type);
if(over)
break;
buf += reclen;
file->f_pos += reclen;
nbytes -= reclen;
}
return 0;
}
#define DIR_BUFSIZE 2048
static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir)
{
struct file *cfile = file->private_data;
char *buf;
int ret;
if(!cfile)
return -EISDIR;
buf = kmalloc(DIR_BUFSIZE, GFP_KERNEL);
if(!buf)
return -ENOMEM;
ret = kernel_read(cfile, file->f_pos, buf, DIR_BUFSIZE);
if(ret < 0)
printk("fuse_readdir: failed to read container file\n");
else
ret = parse_dirfile(buf, ret, file, dstbuf, filldir);
kfree(buf);
return ret;
}
static char *read_link(struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
struct fuse_conn *fc = INO_FC(inode);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_out out = FUSE_OUT_INIT;
char *link;
link = (char *) __get_free_page(GFP_KERNEL);
if(!link)
return ERR_PTR(-ENOMEM);
in.h.opcode = FUSE_READLINK;
in.h.ino = inode->i_ino;
out.argvar = 1;
out.numargs = 1;
out.args[0].size = PAGE_SIZE - 1;
out.args[0].value = link;
request_send(fc, &in, &out);
if(out.h.error) {
free_page((unsigned long) link);
return ERR_PTR(out.h.error);
}
link[out.args[0].size] = '\0';
return link;
}
static void free_link(char *link)
{
if(!IS_ERR(link))
free_page((unsigned long) link);
}
static int fuse_readlink(struct dentry *dentry, char *buffer, int buflen)
{
int ret;
char *link;
link = read_link(dentry);
ret = vfs_readlink(dentry, buffer, buflen, link);
free_link(link);
return ret;
}
static int fuse_follow_link(struct dentry *dentry, struct nameidata *nd)
{
int ret;
char *link;
link = read_link(dentry);
ret = vfs_follow_link(nd, link);
free_link(link);
return ret;
}
static int fuse_dir_open(struct inode *inode, struct file *file)
{
struct fuse_conn *fc = INO_FC(inode);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_out out = FUSE_OUT_INIT;
struct fuse_getdir_out outarg;
in.h.opcode = FUSE_GETDIR;
in.h.ino = inode->i_ino;
out.numargs = 1;
out.args[0].size = sizeof(outarg);
out.args[0].value = &outarg;
request_send(fc, &in, &out);
if(!out.h.error) {
struct file *cfile = outarg.file;
struct inode *inode;
if(!cfile) {
printk("fuse_getdir: invalid file\n");
return -EPROTO;
}
inode = cfile->f_dentry->d_inode;
if(!S_ISREG(inode->i_mode)) {
printk("fuse_getdir: not a regular file\n");
fput(cfile);
return -EPROTO;
}
file->private_data = cfile;
}
return out.h.error;
}
static int fuse_dir_release(struct inode *inode, struct file *file)
{
struct file *cfile = file->private_data;
if(cfile)
fput(cfile);
return 0;
}
static unsigned int iattr_to_fattr(struct iattr *iattr,
struct fuse_attr *fattr)
{
unsigned int ivalid = iattr->ia_valid;
unsigned int fvalid = 0;
memset(fattr, 0, sizeof(*fattr));
if(ivalid & ATTR_MODE)
fvalid |= FATTR_MODE, fattr->mode = iattr->ia_mode;
if(ivalid & ATTR_UID)
fvalid |= FATTR_UID, fattr->uid = iattr->ia_uid;
if(ivalid & ATTR_GID)
fvalid |= FATTR_GID, fattr->gid = iattr->ia_gid;
if(ivalid & ATTR_SIZE)
fvalid |= FATTR_SIZE, fattr->size = iattr->ia_size;
/* You can only _set_ these together (they may change by themselves) */
if((ivalid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME)) {
fvalid |= FATTR_ATIME | FATTR_MTIME;
#ifdef KERNEL_2_6
fattr->atime = iattr->ia_atime.tv_sec;
fattr->mtime = iattr->ia_mtime.tv_sec;
#else
fattr->atime = iattr->ia_atime;
fattr->mtime = iattr->ia_mtime;
#endif
}
return fvalid;
}
static int fuse_setattr(struct dentry *entry, struct iattr *attr)
{
struct inode *inode = entry->d_inode;
struct fuse_conn *fc = INO_FC(inode);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_out out = FUSE_OUT_INIT;
struct fuse_setattr_in inarg;
struct fuse_setattr_out outarg;
memset(&inarg, 0, sizeof(inarg));
inarg.valid = iattr_to_fattr(attr, &inarg.attr);
in.h.opcode = FUSE_SETATTR;
in.h.ino = inode->i_ino;
in.numargs = 1;
in.args[0].size = sizeof(inarg);
in.args[0].value = &inarg;
out.numargs = 1;
out.args[0].size = sizeof(outarg);
out.args[0].value = &outarg;
request_send(fc, &in, &out);
if(!out.h.error) {
if(attr->ia_valid & ATTR_SIZE &&
outarg.attr.size < i_size_read(inode))
vmtruncate(inode, outarg.attr.size);
change_attributes(inode, &outarg.attr);
}
return out.h.error;
}
static int _fuse_dentry_revalidate(struct dentry *entry)
{
if(!entry->d_inode)
return 0;
else if(time_after(jiffies, entry->d_time + FUSE_REVALIDATE_TIME)) {
struct inode *inode = entry->d_inode;
struct fuse_lookup_out outarg;
int version;
int ret;
ret = fuse_do_lookup(entry->d_parent->d_inode, entry, &outarg,
&version);
if(ret)
return 0;
if(outarg.ino != inode->i_ino)
return 0;
change_attributes(inode, &outarg.attr);
inode->i_version = version;
entry->d_time = jiffies;
}
return 1;
}
#ifdef KERNEL_2_6
#define fuse_mknod _fuse_mknod
static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry,
struct kstat *stat)
{
struct inode *inode = entry->d_inode;
int err = fuse_revalidate(entry);
if(!err)
generic_fillattr(inode, stat);
return err;
}
static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
struct nameidata *nd)
{
struct inode *inode;
int err = fuse_lookup_iget(dir, entry, &inode);
if (err)
return ERR_PTR(err);
return d_splice_alias(inode, entry);
}
static int fuse_create(struct inode *dir, struct dentry *entry, int mode,
struct nameidata *nd)
{
return _fuse_create(dir, entry, mode);
}
static int fuse_permission(struct inode *inode, int mask,
struct nameidata *nd)
{
return _fuse_permission(inode, mask);
}
static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd)
{
return _fuse_dentry_revalidate(entry);
}
#else /* KERNEL_2_6 */
#define fuse_create _fuse_create
#define fuse_permission _fuse_permission
static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry)
{
struct inode *inode;
struct dentry *alias;
int err = fuse_lookup_iget(dir, entry, &inode);
if(err)
return ERR_PTR(err);
if(inode && S_ISDIR(inode->i_mode) &&
(alias = d_find_alias(inode)) != NULL) {
dput(alias);
iput(inode);
printk("fuse: cannot assign an existing directory\n");
return ERR_PTR(-EPROTO);
}
d_add(entry, inode);
return NULL;
}
static int fuse_mknod(struct inode *dir, struct dentry *entry, int mode,
int rdev)
{
return fuse_mknod(dir, entry, mode, rdev);
}
static int fuse_dentry_revalidate(struct dentry *entry, int flags)
{
return _fuse_dentry_revalidate(entry);
}
#endif /* KERNEL_2_6 */
static struct inode_operations fuse_dir_inode_operations =
{
.lookup = fuse_lookup,
.create = fuse_create,
.mknod = fuse_mknod,
.mkdir = fuse_mkdir,
.symlink = fuse_symlink,
.unlink = fuse_unlink,
.rmdir = fuse_rmdir,
.rename = fuse_rename,
.link = fuse_link,
.setattr = fuse_setattr,
.permission = fuse_permission,
#ifdef KERNEL_2_6
.getattr = fuse_getattr,
#else
.revalidate = fuse_revalidate,
#endif
};
static struct file_operations fuse_dir_operations = {
.read = generic_read_dir,
.readdir = fuse_readdir,
.open = fuse_dir_open,
.release = fuse_dir_release,
};
static struct inode_operations fuse_file_inode_operations = {
.setattr = fuse_setattr,
.permission = fuse_permission,
#ifdef KERNEL_2_6
.getattr = fuse_getattr,
#else
.revalidate = fuse_revalidate,
#endif
};
static struct inode_operations fuse_symlink_inode_operations =
{
.setattr = fuse_setattr,
.readlink = fuse_readlink,
.follow_link = fuse_follow_link,
#ifdef KERNEL_2_6
.getattr = fuse_getattr,
#else
.revalidate = fuse_revalidate,
#endif
};
static struct dentry_operations fuse_dentry_operations = {
.d_revalidate = fuse_dentry_revalidate,
};
/*
* Local Variables:
* indent-tabs-mode: t
* c-basic-offset: 8
* End:
*/