blob: 55e67e36ae682bcf33a66c2f5e7d936e975e8f6f [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
*
* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/pagemap.h>
#include <linux/mount.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/statfs.h>
#include <linux/magic.h>
#include <linux/fscache.h>
#include <net/9p/9p.h>
#include <net/9p/client.h>
#include "v9fs.h"
#include "v9fs_vfs.h"
#include "fid.h"
#include "xattr.h"
#include "acl.h"
static const struct super_operations v9fs_super_ops, v9fs_super_ops_dotl;
/**
* v9fs_set_super - set the superblock
* @s: super block
* @data: file system specific data
*
*/
static int v9fs_set_super(struct super_block *s, void *data)
{
s->s_fs_info = data;
return set_anon_super(s, data);
}
/**
* v9fs_fill_super - populate superblock with info
* @sb: superblock
* @v9ses: session information
* @flags: flags propagated from v9fs_mount()
*
*/
static int
v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
int flags)
{
int ret;
sb->s_maxbytes = MAX_LFS_FILESIZE;
sb->s_blocksize_bits = fls(v9ses->maxdata - 1);
sb->s_blocksize = 1 << sb->s_blocksize_bits;
sb->s_magic = V9FS_MAGIC;
if (v9fs_proto_dotl(v9ses)) {
sb->s_op = &v9fs_super_ops_dotl;
if (!(v9ses->flags & V9FS_NO_XATTR))
sb->s_xattr = v9fs_xattr_handlers;
} else {
sb->s_op = &v9fs_super_ops;
sb->s_time_max = U32_MAX;
}
sb->s_time_min = 0;
ret = super_setup_bdi(sb);
if (ret)
return ret;
if (!v9ses->cache) {
sb->s_bdi->ra_pages = 0;
sb->s_bdi->io_pages = 0;
} else {
sb->s_bdi->ra_pages = v9ses->maxdata >> PAGE_SHIFT;
sb->s_bdi->io_pages = v9ses->maxdata >> PAGE_SHIFT;
}
sb->s_flags |= SB_ACTIVE;
#ifdef CONFIG_9P_FS_POSIX_ACL
if ((v9ses->flags & V9FS_ACL_MASK) == V9FS_POSIX_ACL)
sb->s_flags |= SB_POSIXACL;
#endif
return 0;
}
/**
* v9fs_mount - mount a superblock
* @fs_type: file system type
* @flags: mount flags
* @dev_name: device name that was mounted
* @data: mount options
*
*/
static struct dentry *v9fs_mount(struct file_system_type *fs_type, int flags,
const char *dev_name, void *data)
{
struct super_block *sb = NULL;
struct inode *inode = NULL;
struct dentry *root = NULL;
struct v9fs_session_info *v9ses = NULL;
struct p9_fid *fid;
int retval = 0;
p9_debug(P9_DEBUG_VFS, "\n");
v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
if (!v9ses)
return ERR_PTR(-ENOMEM);
fid = v9fs_session_init(v9ses, dev_name, data);
if (IS_ERR(fid)) {
retval = PTR_ERR(fid);
goto free_session;
}
sb = sget(fs_type, NULL, v9fs_set_super, flags, v9ses);
if (IS_ERR(sb)) {
retval = PTR_ERR(sb);
goto clunk_fid;
}
retval = v9fs_fill_super(sb, v9ses, flags);
if (retval)
goto release_sb;
if (v9ses->cache & (CACHE_META|CACHE_LOOSE))
sb->s_d_op = &v9fs_cached_dentry_operations;
else
sb->s_d_op = &v9fs_dentry_operations;
inode = v9fs_get_inode_from_fid(v9ses, fid, sb);
if (IS_ERR(inode)) {
retval = PTR_ERR(inode);
goto release_sb;
}
root = d_make_root(inode);
if (!root) {
retval = -ENOMEM;
goto release_sb;
}
sb->s_root = root;
retval = v9fs_get_acl(inode, fid);
if (retval)
goto release_sb;
v9fs_fid_add(root, &fid);
p9_debug(P9_DEBUG_VFS, " simple set mount, return 0\n");
return dget(sb->s_root);
clunk_fid:
p9_fid_put(fid);
v9fs_session_close(v9ses);
free_session:
kfree(v9ses);
return ERR_PTR(retval);
release_sb:
/*
* we will do the session_close and root dentry release
* in the below call. But we need to clunk fid, because we haven't
* attached the fid to dentry so it won't get clunked
* automatically.
*/
p9_fid_put(fid);
deactivate_locked_super(sb);
return ERR_PTR(retval);
}
/**
* v9fs_kill_super - Kill Superblock
* @s: superblock
*
*/
static void v9fs_kill_super(struct super_block *s)
{
struct v9fs_session_info *v9ses = s->s_fs_info;
p9_debug(P9_DEBUG_VFS, " %p\n", s);
kill_anon_super(s);
v9fs_session_cancel(v9ses);
v9fs_session_close(v9ses);
kfree(v9ses);
s->s_fs_info = NULL;
p9_debug(P9_DEBUG_VFS, "exiting kill_super\n");
}
static void
v9fs_umount_begin(struct super_block *sb)
{
struct v9fs_session_info *v9ses;
v9ses = sb->s_fs_info;
v9fs_session_begin_cancel(v9ses);
}
static int v9fs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct v9fs_session_info *v9ses;
struct p9_fid *fid;
struct p9_rstatfs rs;
int res;
fid = v9fs_fid_lookup(dentry);
if (IS_ERR(fid)) {
res = PTR_ERR(fid);
goto done;
}
v9ses = v9fs_dentry2v9ses(dentry);
if (v9fs_proto_dotl(v9ses)) {
res = p9_client_statfs(fid, &rs);
if (res == 0) {
buf->f_type = rs.type;
buf->f_bsize = rs.bsize;
buf->f_blocks = rs.blocks;
buf->f_bfree = rs.bfree;
buf->f_bavail = rs.bavail;
buf->f_files = rs.files;
buf->f_ffree = rs.ffree;
buf->f_fsid = u64_to_fsid(rs.fsid);
buf->f_namelen = rs.namelen;
}
if (res != -ENOSYS)
goto done;
}
res = simple_statfs(dentry, buf);
done:
p9_fid_put(fid);
return res;
}
static int v9fs_drop_inode(struct inode *inode)
{
struct v9fs_session_info *v9ses;
v9ses = v9fs_inode2v9ses(inode);
if (v9ses->cache & (CACHE_META|CACHE_LOOSE))
return generic_drop_inode(inode);
/*
* in case of non cached mode always drop the
* inode because we want the inode attribute
* to always match that on the server.
*/
return 1;
}
static int v9fs_write_inode(struct inode *inode,
struct writeback_control *wbc)
{
/*
* send an fsync request to server irrespective of
* wbc->sync_mode.
*/
p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
return netfs_unpin_writeback(inode, wbc);
}
static int v9fs_write_inode_dotl(struct inode *inode,
struct writeback_control *wbc)
{
p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
return netfs_unpin_writeback(inode, wbc);
}
static const struct super_operations v9fs_super_ops = {
.alloc_inode = v9fs_alloc_inode,
.free_inode = v9fs_free_inode,
.statfs = simple_statfs,
.drop_inode = v9fs_drop_inode,
.evict_inode = v9fs_evict_inode,
.show_options = v9fs_show_options,
.umount_begin = v9fs_umount_begin,
.write_inode = v9fs_write_inode,
};
static const struct super_operations v9fs_super_ops_dotl = {
.alloc_inode = v9fs_alloc_inode,
.free_inode = v9fs_free_inode,
.statfs = v9fs_statfs,
.drop_inode = v9fs_drop_inode,
.evict_inode = v9fs_evict_inode,
.show_options = v9fs_show_options,
.umount_begin = v9fs_umount_begin,
.write_inode = v9fs_write_inode_dotl,
};
struct file_system_type v9fs_fs_type = {
.name = "9p",
.mount = v9fs_mount,
.kill_sb = v9fs_kill_super,
.owner = THIS_MODULE,
.fs_flags = FS_RENAME_DOES_D_MOVE,
};
MODULE_ALIAS_FS("9p");