fs/9p/vfs_super.c - third_party/linux - Git at Google

 /*
  *  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 version 2
  *  as published by the Free Software Foundation.
  *
  *  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/module.h>
 #include <linux/errno.h>
 #include <linux/fs.h>
 #include <linux/file.h>
 #include <linux/stat.h>
 #include <linux/string.h>
 #include <linux/inet.h>
 #include <linux/pagemap.h>
 #include <linux/mount.h>
 #include <linux/idr.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/statfs.h>
 #include <linux/magic.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, void *data)
 {
 	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;
 		sb->s_xattr = v9fs_xattr_handlers;
 	} else
 		sb->s_op = &v9fs_super_ops;

 	ret = super_setup_bdi(sb);
 	if (ret)
 		return ret;

 	if (v9ses->cache)
 		sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024)/PAGE_SIZE;

 	sb->s_flags |= SB_ACTIVE | SB_DIRSYNC;
 	if (!v9ses->cache)
 		sb->s_flags |= SB_SYNCHRONOUS;

 #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;
 	umode_t mode = S_IRWXUGO | S_ISVTX;
 	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, data);
 	if (retval)
 		goto release_sb;

 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
 		sb->s_d_op = &v9fs_cached_dentry_operations;
 	else
 		sb->s_d_op = &v9fs_dentry_operations;

 	inode = v9fs_get_inode(sb, S_IFDIR | mode, 0);
 	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;
 	if (v9fs_proto_dotl(v9ses)) {
 		struct p9_stat_dotl *st = NULL;
 		st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
 		if (IS_ERR(st)) {
 			retval = PTR_ERR(st);
 			goto release_sb;
 		}
 		d_inode(root)->i_ino = v9fs_qid2ino(&st->qid);
 		v9fs_stat2inode_dotl(st, d_inode(root));
 		kfree(st);
 	} else {
 		struct p9_wstat *st = NULL;
 		st = p9_client_stat(fid);
 		if (IS_ERR(st)) {
 			retval = PTR_ERR(st);
 			goto release_sb;
 		}

 		d_inode(root)->i_ino = v9fs_qid2ino(&st->qid);
 		v9fs_stat2inode(st, d_inode(root), sb);

 		p9stat_free(st);
 		kfree(st);
 	}
 	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_client_clunk(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_client_clunk(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.val[0] = rs.fsid & 0xFFFFFFFFUL;
 			buf->f_fsid.val[1] = (rs.fsid >> 32) & 0xFFFFFFFFUL;
 			buf->f_namelen = rs.namelen;
 		}
 		if (res != -ENOSYS)
 			goto done;
 	}
 	res = simple_statfs(dentry, buf);
 done:
 	return res;
 }

 static int v9fs_drop_inode(struct inode *inode)
 {
 	struct v9fs_session_info *v9ses;
 	v9ses = v9fs_inode2v9ses(inode);
 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
 		return generic_drop_inode(inode);
 	/*
 	 * in case of non cached mode always drop the
 	 * 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)
 {
 	int ret;
 	struct p9_wstat wstat;
 	struct v9fs_inode *v9inode;
 	/*
 	 * send an fsync request to server irrespective of
 	 * wbc->sync_mode.
 	 */
 	p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
 	v9inode = V9FS_I(inode);
 	if (!v9inode->writeback_fid)
 		return 0;
 	v9fs_blank_wstat(&wstat);

 	ret = p9_client_wstat(v9inode->writeback_fid, &wstat);
 	if (ret < 0) {
 		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
 		return ret;
 	}
 	return 0;
 }

 static int v9fs_write_inode_dotl(struct inode *inode,
 				 struct writeback_control *wbc)
 {
 	int ret;
 	struct v9fs_inode *v9inode;
 	/*
 	 * send an fsync request to server irrespective of
 	 * wbc->sync_mode.
 	 */
 	v9inode = V9FS_I(inode);
 	p9_debug(P9_DEBUG_VFS, "%s: inode %p, writeback_fid %p\n",
 		 __func__, inode, v9inode->writeback_fid);
 	if (!v9inode->writeback_fid)
 		return 0;

 	ret = p9_client_fsync(v9inode->writeback_fid, 0);
 	if (ret < 0) {
 		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
 		return ret;
 	}
 	return 0;
 }

 static const struct super_operations v9fs_super_ops = {
 	.alloc_inode = v9fs_alloc_inode,
 	.destroy_inode = v9fs_destroy_inode,
 	.statfs = simple_statfs,
 	.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,
 	.destroy_inode = v9fs_destroy_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");
	/*
	* 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 version 2
	* as published by the Free Software Foundation.
	*
	* 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/module.h>
	#include <linux/errno.h>
	#include <linux/fs.h>
	#include <linux/file.h>
	#include <linux/stat.h>
	#include <linux/string.h>
	#include <linux/inet.h>
	#include <linux/pagemap.h>
	#include <linux/mount.h>
	#include <linux/idr.h>
	#include <linux/sched.h>
	#include <linux/slab.h>
	#include <linux/statfs.h>
	#include <linux/magic.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, void *data)
	{
	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;
	sb->s_xattr = v9fs_xattr_handlers;
	} else
	sb->s_op = &v9fs_super_ops;

	ret = super_setup_bdi(sb);
	if (ret)
	return ret;

	if (v9ses->cache)
	sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024)/PAGE_SIZE;

	sb->s_flags \|= SB_ACTIVE \| SB_DIRSYNC;
	if (!v9ses->cache)
	sb->s_flags \|= SB_SYNCHRONOUS;

	#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;
	umode_t mode = S_IRWXUGO \| S_ISVTX;
	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, data);
	if (retval)
	goto release_sb;

	if (v9ses->cache == CACHE_LOOSE \|\| v9ses->cache == CACHE_FSCACHE)
	sb->s_d_op = &v9fs_cached_dentry_operations;
	else
	sb->s_d_op = &v9fs_dentry_operations;

	inode = v9fs_get_inode(sb, S_IFDIR \| mode, 0);
	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;
	if (v9fs_proto_dotl(v9ses)) {
	struct p9_stat_dotl *st = NULL;
	st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
	if (IS_ERR(st)) {
	retval = PTR_ERR(st);
	goto release_sb;
	}
	d_inode(root)->i_ino = v9fs_qid2ino(&st->qid);
	v9fs_stat2inode_dotl(st, d_inode(root));
	kfree(st);
	} else {
	struct p9_wstat *st = NULL;
	st = p9_client_stat(fid);
	if (IS_ERR(st)) {
	retval = PTR_ERR(st);
	goto release_sb;
	}

	d_inode(root)->i_ino = v9fs_qid2ino(&st->qid);
	v9fs_stat2inode(st, d_inode(root), sb);

	p9stat_free(st);
	kfree(st);
	}
	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_client_clunk(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_client_clunk(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.val[0] = rs.fsid & 0xFFFFFFFFUL;
	buf->f_fsid.val[1] = (rs.fsid >> 32) & 0xFFFFFFFFUL;
	buf->f_namelen = rs.namelen;
	}
	if (res != -ENOSYS)
	goto done;
	}
	res = simple_statfs(dentry, buf);
	done:
	return res;
	}

	static int v9fs_drop_inode(struct inode *inode)
	{
	struct v9fs_session_info *v9ses;
	v9ses = v9fs_inode2v9ses(inode);
	if (v9ses->cache == CACHE_LOOSE \|\| v9ses->cache == CACHE_FSCACHE)
	return generic_drop_inode(inode);
	/*
	* in case of non cached mode always drop the
	* 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)
	{
	int ret;
	struct p9_wstat wstat;
	struct v9fs_inode *v9inode;
	/*
	* send an fsync request to server irrespective of
	* wbc->sync_mode.
	*/
	p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
	v9inode = V9FS_I(inode);
	if (!v9inode->writeback_fid)
	return 0;
	v9fs_blank_wstat(&wstat);

	ret = p9_client_wstat(v9inode->writeback_fid, &wstat);
	if (ret < 0) {
	__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
	return ret;
	}
	return 0;
	}

	static int v9fs_write_inode_dotl(struct inode *inode,
	struct writeback_control *wbc)
	{
	int ret;
	struct v9fs_inode *v9inode;
	/*
	* send an fsync request to server irrespective of
	* wbc->sync_mode.
	*/
	v9inode = V9FS_I(inode);
	p9_debug(P9_DEBUG_VFS, "%s: inode %p, writeback_fid %p\n",
	__func__, inode, v9inode->writeback_fid);
	if (!v9inode->writeback_fid)
	return 0;

	ret = p9_client_fsync(v9inode->writeback_fid, 0);
	if (ret < 0) {
	__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
	return ret;
	}
	return 0;
	}

	static const struct super_operations v9fs_super_ops = {
	.alloc_inode = v9fs_alloc_inode,
	.destroy_inode = v9fs_destroy_inode,
	.statfs = simple_statfs,
	.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,
	.destroy_inode = v9fs_destroy_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");