[GitHub/exynos8895/android_kernel_samsung_universal8895.git] / fs / afs / inode.c

/*
 * Copyright (c) 2002 Red Hat, Inc. All rights reserved.
 *
 * This software may be freely redistributed under the terms of the
 * GNU General Public License.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Authors: David Woodhouse <dwmw2@cambridge.redhat.com>
 *          David Howells <dhowells@redhat.com>
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include "volume.h"
#include "vnode.h"
#include "super.h"
#include "internal.h"

struct afs_iget_data {
	struct afs_fid		fid;
	struct afs_volume	*volume;	/* volume on which resides */
};

/*
 * map the AFS file status to the inode member variables
 */
static int afs_inode_map_status(struct afs_vnode *vnode)
{
	struct inode *inode = AFS_VNODE_TO_I(vnode);

	_debug("FS: ft=%d lk=%d sz=%Zu ver=%Lu mod=%hu",
	       vnode->status.type,
	       vnode->status.nlink,
	       vnode->status.size,
	       vnode->status.version,
	       vnode->status.mode);

	switch (vnode->status.type) {
	case AFS_FTYPE_FILE:
		inode->i_mode	= S_IFREG | vnode->status.mode;
		inode->i_op	= &afs_file_inode_operations;
		inode->i_fop	= &generic_ro_fops;
		break;
	case AFS_FTYPE_DIR:
		inode->i_mode	= S_IFDIR | vnode->status.mode;
		inode->i_op	= &afs_dir_inode_operations;
		inode->i_fop	= &afs_dir_file_operations;
		break;
	case AFS_FTYPE_SYMLINK:
		inode->i_mode	= S_IFLNK | vnode->status.mode;
		inode->i_op	= &page_symlink_inode_operations;
		break;
	default:
		printk("kAFS: AFS vnode with undefined type\n");
		return -EBADMSG;
	}

	inode->i_nlink		= vnode->status.nlink;
	inode->i_uid		= vnode->status.owner;
	inode->i_gid		= 0;
	inode->i_size		= vnode->status.size;
	inode->i_ctime.tv_sec	= vnode->status.mtime_server;
	inode->i_ctime.tv_nsec	= 0;
	inode->i_atime		= inode->i_mtime = inode->i_ctime;
	inode->i_blocks		= 0;
	inode->i_version	= vnode->fid.unique;
	inode->i_mapping->a_ops	= &afs_fs_aops;

	/* check to see whether a symbolic link is really a mountpoint */
	if (vnode->status.type == AFS_FTYPE_SYMLINK) {
		afs_mntpt_check_symlink(vnode);

		if (vnode->flags & AFS_VNODE_MOUNTPOINT) {
			inode->i_mode	= S_IFDIR | vnode->status.mode;
			inode->i_op	= &afs_mntpt_inode_operations;
			inode->i_fop	= &afs_mntpt_file_operations;
		}
	}

	return 0;
}

/*
 * attempt to fetch the status of an inode, coelescing multiple simultaneous
 * fetches
 */
static int afs_inode_fetch_status(struct inode *inode)
{
	struct afs_vnode *vnode;
	int ret;

	vnode = AFS_FS_I(inode);

	ret = afs_vnode_fetch_status(vnode);

	if (ret == 0)
		ret = afs_inode_map_status(vnode);

	return ret;
}

/*
 * iget5() comparator
 */
static int afs_iget5_test(struct inode *inode, void *opaque)
{
	struct afs_iget_data *data = opaque;

	return inode->i_ino == data->fid.vnode &&
		inode->i_version == data->fid.unique;
}

/*
 * iget5() inode initialiser
 */
static int afs_iget5_set(struct inode *inode, void *opaque)
{
	struct afs_iget_data *data = opaque;
	struct afs_vnode *vnode = AFS_FS_I(inode);

	inode->i_ino = data->fid.vnode;
	inode->i_version = data->fid.unique;
	vnode->fid = data->fid;
	vnode->volume = data->volume;

	return 0;
}

/*
 * inode retrieval
 */
inline int afs_iget(struct super_block *sb, struct afs_fid *fid,
		    struct inode **_inode)
{
	struct afs_iget_data data = { .fid = *fid };
	struct afs_super_info *as;
	struct afs_vnode *vnode;
	struct inode *inode;
	int ret;

	_enter(",{%u,%u,%u},,", fid->vid, fid->vnode, fid->unique);

	as = sb->s_fs_info;
	data.volume = as->volume;

	inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set,
			     &data);
	if (!inode) {
		_leave(" = -ENOMEM");
		return -ENOMEM;
	}

	vnode = AFS_FS_I(inode);

	/* deal with an existing inode */
	if (!(inode->i_state & I_NEW)) {
		ret = afs_vnode_fetch_status(vnode);
		if (ret == 0)
			*_inode = inode;
		else
			iput(inode);
		_leave(" = %d", ret);
		return ret;
	}

#ifdef AFS_CACHING_SUPPORT
	/* set up caching before reading the status, as fetch-status reads the
	 * first page of symlinks to see if they're really mntpts */
	cachefs_acquire_cookie(vnode->volume->cache,
			       NULL,
			       vnode,
			       &vnode->cache);
#endif

	/* okay... it's a new inode */
	inode->i_flags |= S_NOATIME;
	vnode->flags |= AFS_VNODE_CHANGED;
	ret = afs_inode_fetch_status(inode);
	if (ret<0)
		goto bad_inode;

	/* success */
	unlock_new_inode(inode);

	*_inode = inode;
	_leave(" = 0 [CB { v=%u x=%lu t=%u }]",
	       vnode->cb_version,
	       vnode->cb_timeout.timo_jif,
	       vnode->cb_type);
	return 0;

	/* failure */
bad_inode:
	make_bad_inode(inode);
	unlock_new_inode(inode);
	iput(inode);

	_leave(" = %d [bad]", ret);
	return ret;
}

/*
 * read the attributes of an inode
 */
int afs_inode_getattr(struct vfsmount *mnt, struct dentry *dentry,
		      struct kstat *stat)
{
	struct afs_vnode *vnode;
	struct inode *inode;
	int ret;

	inode = dentry->d_inode;

	_enter("{ ino=%lu v=%lu }", inode->i_ino, inode->i_version);

	vnode = AFS_FS_I(inode);

	ret = afs_inode_fetch_status(inode);
	if (ret == -ENOENT) {
		_leave(" = %d [%d %p]",
		       ret, atomic_read(&dentry->d_count), dentry->d_inode);
		return ret;
	} else if (ret < 0) {
		make_bad_inode(inode);
		_leave(" = %d", ret);
		return ret;
	}

	/* transfer attributes from the inode structure to the stat
	 * structure */
	generic_fillattr(inode, stat);

	_leave(" = 0 CB { v=%u x=%u t=%u }",
	       vnode->cb_version,
	       vnode->cb_expiry,
	       vnode->cb_type);

	return 0;
}

/*
 * clear an AFS inode
 */
void afs_clear_inode(struct inode *inode)
{
	struct afs_vnode *vnode;

	vnode = AFS_FS_I(inode);

	_enter("ino=%lu { vn=%08x v=%u x=%u t=%u }",
	       inode->i_ino,
	       vnode->fid.vnode,
	       vnode->cb_version,
	       vnode->cb_expiry,
	       vnode->cb_type
	       );

	BUG_ON(inode->i_ino != vnode->fid.vnode);

	afs_vnode_give_up_callback(vnode);

#ifdef AFS_CACHING_SUPPORT
	cachefs_relinquish_cookie(vnode->cache, 0);
	vnode->cache = NULL;
#endif

	_leave("");
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright (c) 2002 Red Hat, Inc. All rights reserved.
	3	*
	4	* This software may be freely redistributed under the terms of the
	5	* GNU General Public License.
	6	*
	7	* You should have received a copy of the GNU General Public License
	8	* along with this program; if not, write to the Free Software
	9	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	10	*
	11	* Authors: David Woodhouse <dwmw2@cambridge.redhat.com>
	12	* David Howells <dhowells@redhat.com>
	13	*
	14	*/
	15
	16	#include <linux/kernel.h>
	17	#include <linux/module.h>
	18	#include <linux/init.h>
1da177e4 LT	19	#include <linux/slab.h>
	20	#include <linux/fs.h>
	21	#include <linux/pagemap.h>
	22	#include "volume.h"
	23	#include "vnode.h"
	24	#include "super.h"
	25	#include "internal.h"
	26
	27	struct afs_iget_data {
	28	struct afs_fid fid;
	29	struct afs_volume volume; / volume on which resides */
	30	};
	31
1da177e4 LT	32	/*
	33	* map the AFS file status to the inode member variables
	34	*/
	35	static int afs_inode_map_status(struct afs_vnode *vnode)
	36	{
	37	struct inode *inode = AFS_VNODE_TO_I(vnode);
	38
	39	_debug("FS: ft=%d lk=%d sz=%Zu ver=%Lu mod=%hu",
	40	vnode->status.type,
	41	vnode->status.nlink,
	42	vnode->status.size,
	43	vnode->status.version,
	44	vnode->status.mode);
	45
	46	switch (vnode->status.type) {
	47	case AFS_FTYPE_FILE:
	48	inode->i_mode = S_IFREG \| vnode->status.mode;
	49	inode->i_op = &afs_file_inode_operations;
a463ddd3	50	inode->i_fop = &generic_ro_fops;
1da177e4 LT	51	break;
	52	case AFS_FTYPE_DIR:
	53	inode->i_mode = S_IFDIR \| vnode->status.mode;
	54	inode->i_op = &afs_dir_inode_operations;
	55	inode->i_fop = &afs_dir_file_operations;
	56	break;
	57	case AFS_FTYPE_SYMLINK:
	58	inode->i_mode = S_IFLNK \| vnode->status.mode;
	59	inode->i_op = &page_symlink_inode_operations;
	60	break;
	61	default:
	62	printk("kAFS: AFS vnode with undefined type\n");
	63	return -EBADMSG;
	64	}
	65
	66	inode->i_nlink = vnode->status.nlink;
	67	inode->i_uid = vnode->status.owner;
	68	inode->i_gid = 0;
	69	inode->i_size = vnode->status.size;
	70	inode->i_ctime.tv_sec = vnode->status.mtime_server;
	71	inode->i_ctime.tv_nsec = 0;
	72	inode->i_atime = inode->i_mtime = inode->i_ctime;
1da177e4 LT	73	inode->i_blocks = 0;
	74	inode->i_version = vnode->fid.unique;
	75	inode->i_mapping->a_ops = &afs_fs_aops;
	76
	77	/* check to see whether a symbolic link is really a mountpoint */
	78	if (vnode->status.type == AFS_FTYPE_SYMLINK) {
	79	afs_mntpt_check_symlink(vnode);
	80
	81	if (vnode->flags & AFS_VNODE_MOUNTPOINT) {
	82	inode->i_mode = S_IFDIR \| vnode->status.mode;
	83	inode->i_op = &afs_mntpt_inode_operations;
	84	inode->i_fop = &afs_mntpt_file_operations;
	85	}
	86	}
	87
	88	return 0;
ec26815a	89	}
1da177e4	90
1da177e4 LT	91	/*
	92	* attempt to fetch the status of an inode, coelescing multiple simultaneous
	93	* fetches
	94	*/
	95	static int afs_inode_fetch_status(struct inode *inode)
	96	{
	97	struct afs_vnode *vnode;
	98	int ret;
	99
	100	vnode = AFS_FS_I(inode);
	101
	102	ret = afs_vnode_fetch_status(vnode);
	103
	104	if (ret == 0)
	105	ret = afs_inode_map_status(vnode);
	106
	107	return ret;
ec26815a	108	}
1da177e4	109
1da177e4 LT	110	/*
	111	* iget5() comparator
	112	*/
	113	static int afs_iget5_test(struct inode inode, void opaque)
	114	{
	115	struct afs_iget_data *data = opaque;
	116
	117	return inode->i_ino == data->fid.vnode &&
	118	inode->i_version == data->fid.unique;
ec26815a	119	}
1da177e4	120
1da177e4 LT	121	/*
	122	* iget5() inode initialiser
	123	*/
	124	static int afs_iget5_set(struct inode inode, void opaque)
	125	{
	126	struct afs_iget_data *data = opaque;
	127	struct afs_vnode *vnode = AFS_FS_I(inode);
	128
	129	inode->i_ino = data->fid.vnode;
	130	inode->i_version = data->fid.unique;
	131	vnode->fid = data->fid;
	132	vnode->volume = data->volume;
	133
	134	return 0;
ec26815a	135	}
1da177e4	136
1da177e4 LT	137	/*
	138	* inode retrieval
	139	*/
	140	inline int afs_iget(struct super_block sb, struct afs_fid fid,
	141	struct inode **_inode)
	142	{
	143	struct afs_iget_data data = { .fid = *fid };
	144	struct afs_super_info *as;
	145	struct afs_vnode *vnode;
	146	struct inode *inode;
	147	int ret;
	148
	149	_enter(",{%u,%u,%u},,", fid->vid, fid->vnode, fid->unique);
	150
	151	as = sb->s_fs_info;
	152	data.volume = as->volume;
	153
	154	inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set,
	155	&data);
	156	if (!inode) {
	157	_leave(" = -ENOMEM");
	158	return -ENOMEM;
	159	}
	160
	161	vnode = AFS_FS_I(inode);
	162
	163	/* deal with an existing inode */
	164	if (!(inode->i_state & I_NEW)) {
	165	ret = afs_vnode_fetch_status(vnode);
ec26815a	166	if (ret == 0)
1da177e4 LT	167	*_inode = inode;
	168	else
	169	iput(inode);
	170	_leave(" = %d", ret);
	171	return ret;
	172	}
	173
	174	#ifdef AFS_CACHING_SUPPORT
	175	/* set up caching before reading the status, as fetch-status reads the
	176	* first page of symlinks to see if they're really mntpts */
	177	cachefs_acquire_cookie(vnode->volume->cache,
	178	NULL,
	179	vnode,
	180	&vnode->cache);
	181	#endif
	182
	183	/* okay... it's a new inode */
	184	inode->i_flags \|= S_NOATIME;
	185	vnode->flags \|= AFS_VNODE_CHANGED;
	186	ret = afs_inode_fetch_status(inode);
	187	if (ret<0)
	188	goto bad_inode;
	189
	190	/* success */
	191	unlock_new_inode(inode);
	192
	193	*_inode = inode;
	194	_leave(" = 0 [CB { v=%u x=%lu t=%u }]",
	195	vnode->cb_version,
	196	vnode->cb_timeout.timo_jif,
	197	vnode->cb_type);
	198	return 0;
	199
	200	/* failure */
ec26815a	201	bad_inode:
1da177e4 LT	202	make_bad_inode(inode);
	203	unlock_new_inode(inode);
	204	iput(inode);
	205
	206	_leave(" = %d [bad]", ret);
	207	return ret;
ec26815a	208	}
1da177e4	209
1da177e4 LT	210	/*
	211	* read the attributes of an inode
	212	*/
	213	int afs_inode_getattr(struct vfsmount mnt, struct dentry dentry,
	214	struct kstat *stat)
	215	{
	216	struct afs_vnode *vnode;
	217	struct inode *inode;
	218	int ret;
	219
	220	inode = dentry->d_inode;
	221
	222	_enter("{ ino=%lu v=%lu }", inode->i_ino, inode->i_version);
	223
	224	vnode = AFS_FS_I(inode);
	225
	226	ret = afs_inode_fetch_status(inode);
	227	if (ret == -ENOENT) {
	228	_leave(" = %d [%d %p]",
	229	ret, atomic_read(&dentry->d_count), dentry->d_inode);
	230	return ret;
ec26815a	231	} else if (ret < 0) {
1da177e4 LT	232	make_bad_inode(inode);
	233	_leave(" = %d", ret);
	234	return ret;
	235	}
	236
	237	/* transfer attributes from the inode structure to the stat
	238	* structure */
	239	generic_fillattr(inode, stat);
	240
	241	_leave(" = 0 CB { v=%u x=%u t=%u }",
	242	vnode->cb_version,
	243	vnode->cb_expiry,
	244	vnode->cb_type);
	245
	246	return 0;
ec26815a	247	}
1da177e4	248
1da177e4 LT	249	/*
	250	* clear an AFS inode
	251	*/
	252	void afs_clear_inode(struct inode *inode)
	253	{
	254	struct afs_vnode *vnode;
	255
	256	vnode = AFS_FS_I(inode);
	257
	258	_enter("ino=%lu { vn=%08x v=%u x=%u t=%u }",
	259	inode->i_ino,
	260	vnode->fid.vnode,
	261	vnode->cb_version,
	262	vnode->cb_expiry,
	263	vnode->cb_type
	264	);
	265
	266	BUG_ON(inode->i_ino != vnode->fid.vnode);
	267
	268	afs_vnode_give_up_callback(vnode);
	269
	270	#ifdef AFS_CACHING_SUPPORT
	271	cachefs_relinquish_cookie(vnode->cache, 0);
	272	vnode->cache = NULL;
	273	#endif
	274
	275	_leave("");
ec26815a	276	}