Commit 9e82cf6a authored by Eric Van Hensbergen's avatar Eric Van Hensbergen Committed by Linus Torvalds

[PATCH] v9fs: VFS superblock operations and glue

This part of the patch contains VFS superblock and mapping code.
Signed-off-by: default avatarEric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 2bad8471
This diff is collapsed.
/*
* V9FS definitions.
*
* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to:
* Free Software Foundation
* 51 Franklin Street, Fifth Floor
* Boston, MA 02111-1301 USA
*
*/
/*
* Idpool structure provides lock and id management
*
*/
struct v9fs_idpool {
struct semaphore lock;
struct idr pool;
};
/*
* Session structure provides information for an opened session
*
*/
struct v9fs_session_info {
/* options */
unsigned int maxdata;
unsigned char extended; /* set to 1 if we are using UNIX extensions */
unsigned char nodev; /* set to 1 if no disable device mapping */
unsigned short port; /* port to connect to */
unsigned short debug; /* debug level */
unsigned short proto; /* protocol to use */
unsigned int afid; /* authentication fid */
unsigned int rfdno; /* read file descriptor number */
unsigned int wfdno; /* write file descriptor number */
char *name; /* user name to mount as */
char *remotename; /* name of remote hierarchy being mounted */
unsigned int uid; /* default uid/muid for legacy support */
unsigned int gid; /* default gid for legacy support */
/* book keeping */
struct v9fs_idpool fidpool; /* The FID pool for file descriptors */
struct v9fs_idpool tidpool; /* The TID pool for transactions ids */
/* transport information */
struct v9fs_transport *transport;
int inprogress; /* session in progress => true */
int shutdown; /* session shutting down. no more attaches. */
unsigned char session_hung;
/* mux private data */
struct v9fs_fcall *curfcall;
wait_queue_head_t read_wait;
struct completion fcread;
struct completion proccmpl;
struct task_struct *recvproc;
spinlock_t muxlock;
struct list_head mux_fcalls;
};
/* possible values of ->proto */
enum {
PROTO_TCP,
PROTO_UNIX,
PROTO_FD,
};
int v9fs_session_init(struct v9fs_session_info *, const char *, char *);
struct v9fs_session_info *v9fs_inode2v9ses(struct inode *);
void v9fs_session_close(struct v9fs_session_info *v9ses);
int v9fs_get_idpool(struct v9fs_idpool *p);
void v9fs_put_idpool(int id, struct v9fs_idpool *p);
int v9fs_get_option(char *opts, char *name, char *buf, int buflen);
long long v9fs_get_int_option(char *opts, char *name, long long dflt);
int v9fs_parse_tcp_devname(const char *devname, char **addr, char **remotename);
#define V9FS_MAGIC 0x01021997
/* other default globals */
#define V9FS_PORT 564
#define V9FS_DEFUSER "nobody"
#define V9FS_DEFANAME ""
/* inital pool sizes for fids and tags */
#define V9FS_START_FIDS 8192
#define V9FS_START_TIDS 256
/*
* V9FS VFS extensions.
*
* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to:
* Free Software Foundation
* 51 Franklin Street, Fifth Floor
* Boston, MA 02111-1301 USA
*
*/
/* plan9 semantics are that created files are implicitly opened.
* But linux semantics are that you call create, then open.
* the plan9 approach is superior as it provides an atomic
* open.
* we track the create fid here. When the file is opened, if fidopen is
* non-zero, we use the fid and can skip some steps.
* there may be a better way to do this, but I don't know it.
* one BAD way is to clunk the fid on create, then open it again:
* you lose the atomicity of file open
*/
/* special case:
* unlink calls remove, which is an implicit clunk. So we have to track
* that kind of thing so that we don't try to clunk a dead fid.
*/
extern struct file_system_type v9fs_fs_type;
extern struct file_operations v9fs_file_operations;
extern struct file_operations v9fs_dir_operations;
extern struct dentry_operations v9fs_dentry_operations;
struct inode *v9fs_get_inode(struct super_block *sb, int mode);
ino_t v9fs_qid2ino(struct v9fs_qid *qid);
void v9fs_mistat2inode(struct v9fs_stat *, struct inode *,
struct super_block *);
int v9fs_dir_release(struct inode *inode, struct file *filp);
int v9fs_file_open(struct inode *inode, struct file *file);
void v9fs_inode2mistat(struct inode *inode, struct v9fs_stat *mistat);
void v9fs_dentry_release(struct dentry *);
/*
* linux/fs/9p/vfs_super.c
*
* This file contians superblock ops for 9P2000. It is intended that
* you mount this file system on directories.
*
* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to:
* Free Software Foundation
* 51 Franklin Street, Fifth Floor
* Boston, MA 02111-1301 USA
*
*/
#include <linux/kernel.h>
#include <linux/config.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/smp_lock.h>
#include <linux/inet.h>
#include <linux/pagemap.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include <linux/idr.h>
#include "debug.h"
#include "v9fs.h"
#include "9p.h"
#include "v9fs_vfs.h"
#include "conv.h"
#include "fid.h"
static void v9fs_clear_inode(struct inode *);
static struct super_operations v9fs_super_ops;
/**
* v9fs_clear_inode - release an inode
* @inode: inode to release
*
*/
static void v9fs_clear_inode(struct inode *inode)
{
filemap_fdatawrite(inode->i_mapping);
}
/**
* 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
*
*/
static void
v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
int flags)
{
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;
sb->s_op = &v9fs_super_ops;
sb->s_flags = flags | MS_ACTIVE | MS_SYNCHRONOUS | MS_DIRSYNC |
MS_NODIRATIME | MS_NOATIME;
}
/**
* v9fs_get_sb - mount a superblock
* @fs_type: file system type
* @flags: mount flags
* @dev_name: device name that was mounted
* @data: mount options
*
*/
static struct super_block *v9fs_get_sb(struct file_system_type
*fs_type, int flags,
const char *dev_name, void *data)
{
struct super_block *sb = NULL;
struct v9fs_fcall *fcall = NULL;
struct inode *inode = NULL;
struct dentry *root = NULL;
struct v9fs_session_info *v9ses = NULL;
struct v9fs_fid *root_fid = NULL;
int mode = S_IRWXUGO | S_ISVTX;
uid_t uid = current->fsuid;
gid_t gid = current->fsgid;
int stat_result = 0;
int newfid = 0;
int retval = 0;
dprintk(DEBUG_VFS, " \n");
v9ses = kcalloc(1, sizeof(struct v9fs_session_info), GFP_KERNEL);
if (!v9ses)
return ERR_PTR(-ENOMEM);
if ((newfid = v9fs_session_init(v9ses, dev_name, data)) < 0) {
dprintk(DEBUG_ERROR, "problem initiating session\n");
retval = newfid;
goto free_session;
}
sb = sget(fs_type, NULL, v9fs_set_super, v9ses);
v9fs_fill_super(sb, v9ses, flags);
inode = v9fs_get_inode(sb, S_IFDIR | mode);
if (IS_ERR(inode)) {
retval = PTR_ERR(inode);
goto put_back_sb;
}
inode->i_uid = uid;
inode->i_gid = gid;
root = d_alloc_root(inode);
if (!root) {
retval = -ENOMEM;
goto release_inode;
}
sb->s_root = root;
/* Setup the Root Inode */
root_fid = v9fs_fid_create(root);
if (root_fid == NULL) {
retval = -ENOMEM;
goto release_dentry;
}
root_fid->fidopen = 0;
root_fid->v9ses = v9ses;
stat_result = v9fs_t_stat(v9ses, newfid, &fcall);
if (stat_result < 0) {
dprintk(DEBUG_ERROR, "stat error\n");
v9fs_t_clunk(v9ses, newfid, NULL);
v9fs_put_idpool(newfid, &v9ses->fidpool);
} else {
root_fid->fid = newfid;
root_fid->qid = fcall->params.rstat.stat->qid;
root->d_inode->i_ino =
v9fs_qid2ino(&fcall->params.rstat.stat->qid);
v9fs_mistat2inode(fcall->params.rstat.stat, root->d_inode, sb);
}
kfree(fcall);
if (stat_result < 0) {
retval = stat_result;
goto release_dentry;
}
return sb;
release_dentry:
dput(sb->s_root);
release_inode:
iput(inode);
put_back_sb:
up_write(&sb->s_umount);
deactivate_super(sb);
v9fs_session_close(v9ses);
free_session:
kfree(v9ses);
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;
dprintk(DEBUG_VFS, " %p\n", s);
v9fs_dentry_release(s->s_root); /* clunk root */
kill_anon_super(s);
v9fs_session_close(v9ses);
kfree(v9ses);
dprintk(DEBUG_VFS, "exiting kill_super\n");
}
/**
* v9fs_show_options - Show mount options in /proc/mounts
* @m: seq_file to write to
* @mnt: mount descriptor
*
*/
static int v9fs_show_options(struct seq_file *m, struct vfsmount *mnt)
{
struct v9fs_session_info *v9ses = mnt->mnt_sb->s_fs_info;
if (v9ses->debug != 0)
seq_printf(m, ",debug=%u", v9ses->debug);
if (v9ses->port != V9FS_PORT)
seq_printf(m, ",port=%u", v9ses->port);
if (v9ses->maxdata != 9000)
seq_printf(m, ",msize=%u", v9ses->maxdata);
if (v9ses->afid != ~0)
seq_printf(m, ",afid=%u", v9ses->afid);
if (v9ses->proto == PROTO_UNIX)
seq_puts(m, ",proto=unix");
if (v9ses->extended == 0)
seq_puts(m, ",noextend");
if (v9ses->nodev == 1)
seq_puts(m, ",nodevmap");
seq_printf(m, ",name=%s", v9ses->name);
seq_printf(m, ",aname=%s", v9ses->remotename);
seq_printf(m, ",uid=%u", v9ses->uid);
seq_printf(m, ",gid=%u", v9ses->gid);
return 0;
}
static struct super_operations v9fs_super_ops = {
.statfs = simple_statfs,
.clear_inode = v9fs_clear_inode,
.show_options = v9fs_show_options,
};
struct file_system_type v9fs_fs_type = {
.name = "9P",
.get_sb = v9fs_get_sb,
.kill_sb = v9fs_kill_super,
.owner = THIS_MODULE,
};
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