[apple/xnu.git] / bsd / hfs / hfs_link.c

/*
 * Copyright (c) 1999-2003 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */


#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/stat.h>
#include <sys/vnode.h>
#include <vfs/vfs_support.h>
#include <libkern/libkern.h>

#include "hfs.h"
#include "hfs_catalog.h"
#include "hfs_format.h"
#include "hfs_endian.h"


/*
 * Create a new indirect link
 *
 * An indirect link is a reference to a data node.  The only useable
 * fields in the link are the link number, parentID, name and text
 * encoding.  All other catalog fields are ignored.
 */
static int
createindirectlink(struct hfsmount *hfsmp, u_int32_t linknum,
			u_int32_t linkparid, char *linkName, cnid_t *linkcnid)
{
	struct FndrFileInfo *fip;
	struct cat_desc desc;
	struct cat_attr attr;
	int result;

	/* Setup the descriptor */
	bzero(&desc, sizeof(desc));
	desc.cd_nameptr = linkName;
	desc.cd_namelen = strlen(linkName);
	desc.cd_parentcnid = linkparid;

	/* Setup the default attributes */
	bzero(&attr, sizeof(attr));
	
	/* links are matched to data nodes by link ID and to volumes by create date */
	attr.ca_rdev = linknum;  /* note: cat backend overloads ca_rdev to be the linknum when nlink = 0 */
	attr.ca_itime = HFSTOVCB(hfsmp)->vcbCrDate;
	attr.ca_mode = S_IFREG;

	fip = (struct FndrFileInfo *)&attr.ca_finderinfo;
	fip->fdType    = SWAP_BE32 (kHardLinkFileType);	/* 'hlnk' */
	fip->fdCreator = SWAP_BE32 (kHFSPlusCreator);	/* 'hfs+' */
	fip->fdFlags   = SWAP_BE16 (kHasBeenInited);

	hfs_global_shared_lock_acquire(hfsmp);
	if (hfsmp->jnl) {
	    if (journal_start_transaction(hfsmp->jnl) != 0) {
			hfs_global_shared_lock_release(hfsmp);
			return EINVAL;
	    }
	}

	/* Create the indirect link directly in the catalog */
	result = cat_create(hfsmp, &desc, &attr, NULL);

	if (result == 0 && linkcnid != NULL)
		*linkcnid = attr.ca_fileid;

	if (hfsmp->jnl) {
	    journal_end_transaction(hfsmp->jnl);
	}
	hfs_global_shared_lock_release(hfsmp);

	return (result);
}


/*
 * 2 locks are needed (dvp and vp)
 * also need catalog lock
 *
 * caller's responsibility:
 *		componentname cleanup
 *		unlocking dvp and vp
 */
static int
hfs_makelink(struct hfsmount *hfsmp, struct cnode *cp, struct cnode *dcp,
		struct componentname *cnp)
{
	struct proc *p = cnp->cn_proc;
	u_int32_t indnodeno = 0;
	char inodename[32];
	struct cat_desc to_desc;
	int newlink = 0;
	int retval;
	cat_cookie_t cookie = {0};


	/* We don't allow link nodes in our Private Meta Data folder! */
	if (dcp->c_fileid == hfsmp->hfs_privdir_desc.cd_cnid)
		return (EPERM);

	if (hfs_freeblks(hfsmp, 0) == 0)
		return (ENOSPC);

	/* Reserve some space in the Catalog file. */
	if ((retval = cat_preflight(hfsmp, (2 * CAT_CREATE)+ CAT_RENAME, &cookie, p))) {
		return (retval);
	}

	/* Lock catalog b-tree */
	retval = hfs_metafilelocking(hfsmp, kHFSCatalogFileID, LK_EXCLUSIVE, p);
	if (retval) {
	   goto out2;
	}

	/*
	 * If this is a new hardlink then we need to create the data
	 * node (inode) and replace the original file with a link node.
	 */
	if (cp->c_nlink == 2 && (cp->c_flag & C_HARDLINK) == 0) {
		newlink = 1;
		bzero(&to_desc, sizeof(to_desc));
		to_desc.cd_parentcnid = hfsmp->hfs_privdir_desc.cd_cnid;
		to_desc.cd_cnid = cp->c_fileid;

		do {
			/* get a unique indirect node number */
			indnodeno = ((random() & 0x3fffffff) + 100);
			MAKE_INODE_NAME(inodename, indnodeno);

			/* move source file to data node directory */
			to_desc.cd_nameptr = inodename;
			to_desc.cd_namelen = strlen(inodename);
		
			retval = cat_rename(hfsmp, &cp->c_desc, &hfsmp->hfs_privdir_desc,
					&to_desc, NULL);

		} while (retval == EEXIST);
		if (retval)
			goto out;

		/* Replace source file with link node */
		retval = createindirectlink(hfsmp, indnodeno, cp->c_parentcnid,
				cp->c_desc.cd_nameptr, &cp->c_desc.cd_cnid);
		if (retval) {
			/* put it source file back */
		// XXXdbg
		#if 1
		    {
		    	int err;
				err = cat_rename(hfsmp, &to_desc, &dcp->c_desc, &cp->c_desc, NULL);
				if (err)
					panic("hfs_makelink: error %d from cat_rename backout 1", err);
		    }
		#else
			(void) cat_rename(hfsmp, &to_desc, &dcp->c_desc, &cp->c_desc, NULL);
		#endif
			goto out;
		}
		cp->c_rdev = indnodeno;
	} else {
		indnodeno = cp->c_rdev;
	}

	/*
	 * Create a catalog entry for the new link (parentID + name).
	 */
	retval = createindirectlink(hfsmp, indnodeno, dcp->c_fileid, cnp->cn_nameptr, NULL);
	if (retval && newlink) {
		/* Get rid of new link */
		(void) cat_delete(hfsmp, &cp->c_desc, &cp->c_attr);

		/* Put the source file back */
	// XXXdbg
	#if 1
		{
			int err;
			err = cat_rename(hfsmp, &to_desc, &dcp->c_desc, &cp->c_desc, NULL);
			if (err)
				panic("hfs_makelink: error %d from cat_rename backout 2", err);
		}
	#else
		(void) cat_rename(hfsmp, &to_desc, &dcp->c_desc, &cp->c_desc, NULL);
	#endif
		goto out;
	}

	/*
	 * Finally, if this is a new hardlink then:
	 *  - update HFS Private Data dir
	 *  - mark the cnode as a hard link
	 */
	if (newlink) {
		hfsmp->hfs_privdir_attr.ca_entries++;
		(void)cat_update(hfsmp, &hfsmp->hfs_privdir_desc,
			&hfsmp->hfs_privdir_attr, NULL, NULL);
		hfs_volupdate(hfsmp, VOL_MKFILE, 0);
		cp->c_flag |= (C_CHANGE | C_HARDLINK);
	}

out:
	/* Unlock catalog b-tree */
	(void) hfs_metafilelocking(hfsmp, kHFSCatalogFileID, LK_RELEASE, p);
out2:
	cat_postflight(hfsmp, &cookie, p);
	return (retval);
}


/*
 * link vnode call
#% link		vp	U U U
#% link		tdvp	L U U
#
 vop_link {
     IN WILLRELE struct vnode *vp;
     IN struct vnode *targetPar_vp;
     IN struct componentname *cnp;

     */
__private_extern__
int
hfs_link(ap)
	struct vop_link_args /* {
		struct vnode *a_vp;
		struct vnode *a_tdvp;
		struct componentname *a_cnp;
	} */ *ap;
{
	struct hfsmount *hfsmp;
	struct vnode *vp = ap->a_vp;
	struct vnode *tdvp = ap->a_tdvp;
	struct componentname *cnp = ap->a_cnp;
	struct proc *p = cnp->cn_proc;
	struct cnode *cp;
	struct cnode *tdcp;
	struct timeval tv;
	int error;

	hfsmp = VTOHFS(vp);
	
#if HFS_DIAGNOSTIC
	if ((cnp->cn_flags & HASBUF) == 0)
		panic("hfs_link: no name");
#endif
	if (tdvp->v_mount != vp->v_mount) {
		VOP_ABORTOP(tdvp, cnp);
		error = EXDEV;
		goto out2;
	}
	if (VTOVCB(tdvp)->vcbSigWord != kHFSPlusSigWord)
		return err_link(ap);	/* hfs disks don't support hard links */
	
	if (hfsmp->hfs_privdir_desc.cd_cnid == 0)
		return err_link(ap);	/* no private metadata dir, no links possible */

	if (tdvp != vp && (error = vn_lock(vp, LK_EXCLUSIVE, p))) {
		VOP_ABORTOP(tdvp, cnp);
		goto out2;
	}
	cp = VTOC(vp);
	tdcp = VTOC(tdvp);

	if (cp->c_nlink >= HFS_LINK_MAX) {
		VOP_ABORTOP(tdvp, cnp);
		error = EMLINK;
		goto out1;
	}
	if (cp->c_flags & (IMMUTABLE | APPEND)) {
		VOP_ABORTOP(tdvp, cnp);
		error = EPERM;
		goto out1;
	}
	if (vp->v_type == VBLK || vp->v_type == VCHR) {
		VOP_ABORTOP(tdvp, cnp);
		error = EINVAL;  /* cannot link to a special file */
		goto out1;
	}

	hfs_global_shared_lock_acquire(hfsmp);
	if (hfsmp->jnl) {
	    if (journal_start_transaction(hfsmp->jnl) != 0) {
			hfs_global_shared_lock_release(hfsmp);
			VOP_ABORTOP(tdvp, cnp);
			error = EINVAL;  /* cannot link to a special file */
			goto out1;
	    }
	}

	cp->c_nlink++;
	cp->c_flag |= C_CHANGE;
	tv = time;

	error = VOP_UPDATE(vp, &tv, &tv, 1);
	if (!error) {
		error = hfs_makelink(hfsmp, cp, tdcp, cnp);
	}
	if (error) {
		cp->c_nlink--;
		cp->c_flag |= C_CHANGE;
	} else {
		/* Update the target directory and volume stats */
		tdcp->c_nlink++;
		tdcp->c_entries++;
		tdcp->c_flag |= C_CHANGE | C_UPDATE;
		tv = time;
		(void) VOP_UPDATE(tdvp, &tv, &tv, 0);

		hfs_volupdate(hfsmp, VOL_MKFILE,
			(tdcp->c_cnid == kHFSRootFolderID));
	}

	// XXXdbg - need to do this here as well because cp could have changed
	(void) VOP_UPDATE(vp, &tv, &tv, 1);


	if (hfsmp->jnl) {
	    journal_end_transaction(hfsmp->jnl);
	}
	hfs_global_shared_lock_release(hfsmp);

	/* free the pathname buffer */
	{
		char *tmp = cnp->cn_pnbuf;
		cnp->cn_pnbuf = NULL;
		cnp->cn_flags &= ~HASBUF;
		FREE_ZONE(tmp, cnp->cn_pnlen, M_NAMEI);
	}
	
	HFS_KNOTE(vp, NOTE_LINK);
	HFS_KNOTE(tdvp, NOTE_WRITE);

out1:
	if (tdvp != vp)
		VOP_UNLOCK(vp, 0, p);
out2:
	vput(tdvp);
	return (error);
}
Commit	Line	Data
1c79356b	1	/*
55e303ae	2	* Copyright (c) 1999-2003 Apple Computer, Inc. All rights reserved.
1c79356b A	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
e5568f75 A	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
1c79356b	11	*
e5568f75 A	12	* This Original Code and all software distributed under the License are
e5568f75 A	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
e5568f75 A	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
1c79356b A	19	*
	20	* @APPLE_LICENSE_HEADER_END@
	21	*/
	22
1c79356b A	23
	24	#include <sys/systm.h>
	25	#include <sys/kernel.h>
	26	#include <sys/malloc.h>
9bccf70c	27	#include <sys/mount.h>
1c79356b A	28	#include <sys/namei.h>
	29	#include <sys/stat.h>
	30	#include <sys/vnode.h>
	31	#include <vfs/vfs_support.h>
	32	#include <libkern/libkern.h>
	33
	34	#include "hfs.h"
9bccf70c A	35	#include "hfs_catalog.h"
	36	#include "hfs_format.h"
	37	#include "hfs_endian.h"
1c79356b A	38
	39
	40	/*
	41	* Create a new indirect link
	42	*
9bccf70c A	43	* An indirect link is a reference to a data node. The only useable
	44	* fields in the link are the link number, parentID, name and text
	45	* encoding. All other catalog fields are ignored.
1c79356b A	46	*/
1c79356b A	47	static int
9bccf70c A	48	createindirectlink(struct hfsmount *hfsmp, u_int32_t linknum,
9bccf70c A	49	u_int32_t linkparid, char linkName, cnid_t linkcnid)
1c79356b	50	{
9bccf70c A	51	struct FndrFileInfo *fip;
	52	struct cat_desc desc;
	53	struct cat_attr attr;
1c79356b A	54	int result;
1c79356b A	55
9bccf70c A	56	/* Setup the descriptor */
	57	bzero(&desc, sizeof(desc));
	58	desc.cd_nameptr = linkName;
	59	desc.cd_namelen = strlen(linkName);
	60	desc.cd_parentcnid = linkparid;
1c79356b	61
9bccf70c A	62	/* Setup the default attributes */
	63	bzero(&attr, sizeof(attr));
	64
	65	/* links are matched to data nodes by link ID and to volumes by create date */
	66	attr.ca_rdev = linknum; /* note: cat backend overloads ca_rdev to be the linknum when nlink = 0 */
	67	attr.ca_itime = HFSTOVCB(hfsmp)->vcbCrDate;
	68	attr.ca_mode = S_IFREG;
1c79356b	69
9bccf70c A	70	fip = (struct FndrFileInfo *)&attr.ca_finderinfo;
	71	fip->fdType = SWAP_BE32 (kHardLinkFileType); /* 'hlnk' */
	72	fip->fdCreator = SWAP_BE32 (kHFSPlusCreator); /* 'hfs+' */
	73	fip->fdFlags = SWAP_BE16 (kHasBeenInited);
1c79356b	74
b4c24cb9 A	75	hfs_global_shared_lock_acquire(hfsmp);
	76	if (hfsmp->jnl) {
	77	if (journal_start_transaction(hfsmp->jnl) != 0) {
	78	hfs_global_shared_lock_release(hfsmp);
	79	return EINVAL;
	80	}
	81	}
	82
9bccf70c A	83	/* Create the indirect link directly in the catalog */
9bccf70c A	84	result = cat_create(hfsmp, &desc, &attr, NULL);
1c79356b	85
b4c24cb9	86	if (result == 0 && linkcnid != NULL)
9bccf70c	87	*linkcnid = attr.ca_fileid;
1c79356b	88
b4c24cb9 A	89	if (hfsmp->jnl) {
	90	journal_end_transaction(hfsmp->jnl);
	91	}
	92	hfs_global_shared_lock_release(hfsmp);
	93
1c79356b A	94	return (result);
	95	}
	96
	97
	98	/*
9bccf70c	99	* 2 locks are needed (dvp and vp)
1c79356b A	100	* also need catalog lock
	101	*
	102	* caller's responsibility:
	103	* componentname cleanup
9bccf70c	104	* unlocking dvp and vp
1c79356b A	105	*/
1c79356b A	106	static int
9bccf70c A	107	hfs_makelink(struct hfsmount hfsmp, struct cnode cp, struct cnode *dcp,
9bccf70c A	108	struct componentname *cnp)
1c79356b A	109	{
1c79356b A	110	struct proc *p = cnp->cn_proc;
1c79356b A	111	u_int32_t indnodeno = 0;
1c79356b A	112	char inodename[32];
9bccf70c A	113	struct cat_desc to_desc;
9bccf70c A	114	int newlink = 0;
1c79356b	115	int retval;
55e303ae	116	cat_cookie_t cookie = {0};
1c79356b	117
1c79356b A	118
1c79356b A	119	/* We don't allow link nodes in our Private Meta Data folder! */
9bccf70c	120	if (dcp->c_fileid == hfsmp->hfs_privdir_desc.cd_cnid)
1c79356b A	121	return (EPERM);
1c79356b A	122
9bccf70c	123	if (hfs_freeblks(hfsmp, 0) == 0)
1c79356b A	124	return (ENOSPC);
1c79356b A	125
55e303ae A	126	/* Reserve some space in the Catalog file. */
	127	if ((retval = cat_preflight(hfsmp, (2 * CAT_CREATE)+ CAT_RENAME, &cookie, p))) {
	128	return (retval);
	129	}
	130
9bccf70c A	131	/* Lock catalog b-tree */
9bccf70c A	132	retval = hfs_metafilelocking(hfsmp, kHFSCatalogFileID, LK_EXCLUSIVE, p);
b4c24cb9	133	if (retval) {
55e303ae	134	goto out2;
b4c24cb9	135	}
1c79356b A	136
	137	/*
	138	* If this is a new hardlink then we need to create the data
	139	* node (inode) and replace the original file with a link node.
	140	*/
9bccf70c A	141	if (cp->c_nlink == 2 && (cp->c_flag & C_HARDLINK) == 0) {
	142	newlink = 1;
	143	bzero(&to_desc, sizeof(to_desc));
	144	to_desc.cd_parentcnid = hfsmp->hfs_privdir_desc.cd_cnid;
	145	to_desc.cd_cnid = cp->c_fileid;
b4c24cb9	146
1c79356b A	147	do {
	148	/* get a unique indirect node number */
	149	indnodeno = ((random() & 0x3fffffff) + 100);
	150	MAKE_INODE_NAME(inodename, indnodeno);
	151
	152	/* move source file to data node directory */
9bccf70c A	153	to_desc.cd_nameptr = inodename;
	154	to_desc.cd_namelen = strlen(inodename);
	155
	156	retval = cat_rename(hfsmp, &cp->c_desc, &hfsmp->hfs_privdir_desc,
	157	&to_desc, NULL);
1c79356b	158
9bccf70c A	159	} while (retval == EEXIST);
	160	if (retval)
	161	goto out;
1c79356b	162
9bccf70c A	163	/* Replace source file with link node */
	164	retval = createindirectlink(hfsmp, indnodeno, cp->c_parentcnid,
	165	cp->c_desc.cd_nameptr, &cp->c_desc.cd_cnid);
1c79356b A	166	if (retval) {
1c79356b A	167	/* put it source file back */
b4c24cb9 A	168	// XXXdbg
	169	#if 1
	170	{
	171	int err;
	172	err = cat_rename(hfsmp, &to_desc, &dcp->c_desc, &cp->c_desc, NULL);
	173	if (err)
	174	panic("hfs_makelink: error %d from cat_rename backout 1", err);
	175	}
	176	#else
9bccf70c	177	(void) cat_rename(hfsmp, &to_desc, &dcp->c_desc, &cp->c_desc, NULL);
b4c24cb9	178	#endif
1c79356b A	179	goto out;
1c79356b A	180	}
9bccf70c A	181	cp->c_rdev = indnodeno;
	182	} else {
	183	indnodeno = cp->c_rdev;
	184	}
1c79356b A	185
	186	/*
	187	* Create a catalog entry for the new link (parentID + name).
	188	*/
9bccf70c A	189	retval = createindirectlink(hfsmp, indnodeno, dcp->c_fileid, cnp->cn_nameptr, NULL);
	190	if (retval && newlink) {
	191	/* Get rid of new link */
	192	(void) cat_delete(hfsmp, &cp->c_desc, &cp->c_attr);
	193
	194	/* Put the source file back */
b4c24cb9 A	195	// XXXdbg
	196	#if 1
	197	{
	198	int err;
	199	err = cat_rename(hfsmp, &to_desc, &dcp->c_desc, &cp->c_desc, NULL);
	200	if (err)
	201	panic("hfs_makelink: error %d from cat_rename backout 2", err);
	202	}
	203	#else
9bccf70c	204	(void) cat_rename(hfsmp, &to_desc, &dcp->c_desc, &cp->c_desc, NULL);
b4c24cb9	205	#endif
1c79356b A	206	goto out;
	207	}
	208
	209	/*
9bccf70c A	210	* Finally, if this is a new hardlink then:
	211	* - update HFS Private Data dir
	212	* - mark the cnode as a hard link
1c79356b	213	*/
9bccf70c A	214	if (newlink) {
	215	hfsmp->hfs_privdir_attr.ca_entries++;
	216	(void)cat_update(hfsmp, &hfsmp->hfs_privdir_desc,
	217	&hfsmp->hfs_privdir_attr, NULL, NULL);
	218	hfs_volupdate(hfsmp, VOL_MKFILE, 0);
	219	cp->c_flag \|= (C_CHANGE \| C_HARDLINK);
1c79356b A	220	}
	221
	222	out:
9bccf70c A	223	/* Unlock catalog b-tree */
9bccf70c A	224	(void) hfs_metafilelocking(hfsmp, kHFSCatalogFileID, LK_RELEASE, p);
55e303ae A	225	out2:
55e303ae A	226	cat_postflight(hfsmp, &cookie, p);
1c79356b A	227	return (retval);
	228	}
	229
	230
	231	/*
	232	* link vnode call
	233	#% link vp U U U
	234	#% link tdvp L U U
	235	#
	236	vop_link {
	237	IN WILLRELE struct vnode *vp;
	238	IN struct vnode *targetPar_vp;
	239	IN struct componentname *cnp;
	240
	241	*/
55e303ae	242	__private_extern__
1c79356b A	243	int
1c79356b A	244	hfs_link(ap)
9bccf70c A	245	struct vop_link_args /* {
	246	struct vnode *a_vp;
	247	struct vnode *a_tdvp;
	248	struct componentname *a_cnp;
	249	} / ap;
1c79356b	250	{
b4c24cb9	251	struct hfsmount *hfsmp;
1c79356b A	252	struct vnode *vp = ap->a_vp;
	253	struct vnode *tdvp = ap->a_tdvp;
	254	struct componentname *cnp = ap->a_cnp;
	255	struct proc *p = cnp->cn_proc;
9bccf70c A	256	struct cnode *cp;
9bccf70c A	257	struct cnode *tdcp;
1c79356b A	258	struct timeval tv;
	259	int error;
	260
b4c24cb9 A	261	hfsmp = VTOHFS(vp);
b4c24cb9 A	262
1c79356b A	263	#if HFS_DIAGNOSTIC
	264	if ((cnp->cn_flags & HASBUF) == 0)
	265	panic("hfs_link: no name");
	266	#endif
	267	if (tdvp->v_mount != vp->v_mount) {
	268	VOP_ABORTOP(tdvp, cnp);
	269	error = EXDEV;
	270	goto out2;
	271	}
	272	if (VTOVCB(tdvp)->vcbSigWord != kHFSPlusSigWord)
	273	return err_link(ap); /* hfs disks don't support hard links */
	274
55e303ae	275	if (hfsmp->hfs_privdir_desc.cd_cnid == 0)
1c79356b A	276	return err_link(ap); /* no private metadata dir, no links possible */
	277
	278	if (tdvp != vp && (error = vn_lock(vp, LK_EXCLUSIVE, p))) {
	279	VOP_ABORTOP(tdvp, cnp);
	280	goto out2;
	281	}
9bccf70c A	282	cp = VTOC(vp);
	283	tdcp = VTOC(tdvp);
	284
	285	if (cp->c_nlink >= HFS_LINK_MAX) {
1c79356b A	286	VOP_ABORTOP(tdvp, cnp);
	287	error = EMLINK;
	288	goto out1;
	289	}
9bccf70c	290	if (cp->c_flags & (IMMUTABLE \| APPEND)) {
1c79356b A	291	VOP_ABORTOP(tdvp, cnp);
	292	error = EPERM;
	293	goto out1;
	294	}
	295	if (vp->v_type == VBLK \|\| vp->v_type == VCHR) {
	296	VOP_ABORTOP(tdvp, cnp);
	297	error = EINVAL; /* cannot link to a special file */
	298	goto out1;
	299	}
	300
b4c24cb9 A	301	hfs_global_shared_lock_acquire(hfsmp);
	302	if (hfsmp->jnl) {
	303	if (journal_start_transaction(hfsmp->jnl) != 0) {
	304	hfs_global_shared_lock_release(hfsmp);
d7e50217 A	305	VOP_ABORTOP(tdvp, cnp);
	306	error = EINVAL; /* cannot link to a special file */
	307	goto out1;
b4c24cb9 A	308	}
	309	}
	310
9bccf70c A	311	cp->c_nlink++;
9bccf70c A	312	cp->c_flag \|= C_CHANGE;
1c79356b	313	tv = time;
b4c24cb9	314
1c79356b	315	error = VOP_UPDATE(vp, &tv, &tv, 1);
b4c24cb9 A	316	if (!error) {
	317	error = hfs_makelink(hfsmp, cp, tdcp, cnp);
	318	}
1c79356b	319	if (error) {
9bccf70c A	320	cp->c_nlink--;
	321	cp->c_flag \|= C_CHANGE;
	322	} else {
	323	/* Update the target directory and volume stats */
	324	tdcp->c_nlink++;
	325	tdcp->c_entries++;
	326	tdcp->c_flag \|= C_CHANGE \| C_UPDATE;
	327	tv = time;
	328	(void) VOP_UPDATE(tdvp, &tv, &tv, 0);
b4c24cb9 A	329
b4c24cb9 A	330	hfs_volupdate(hfsmp, VOL_MKFILE,
9bccf70c	331	(tdcp->c_cnid == kHFSRootFolderID));
1c79356b	332	}
b4c24cb9 A	333
b4c24cb9 A	334	// XXXdbg - need to do this here as well because cp could have changed
483a1d10	335	(void) VOP_UPDATE(vp, &tv, &tv, 1);
b4c24cb9	336
b4c24cb9 A	337
	338	if (hfsmp->jnl) {
	339	journal_end_transaction(hfsmp->jnl);
	340	}
	341	hfs_global_shared_lock_release(hfsmp);
	342
55e303ae A	343	/* free the pathname buffer */
	344	{
	345	char *tmp = cnp->cn_pnbuf;
	346	cnp->cn_pnbuf = NULL;
	347	cnp->cn_flags &= ~HASBUF;
	348	FREE_ZONE(tmp, cnp->cn_pnlen, M_NAMEI);
	349	}
	350
	351	HFS_KNOTE(vp, NOTE_LINK);
	352	HFS_KNOTE(tdvp, NOTE_WRITE);
	353
1c79356b A	354	out1:
	355	if (tdvp != vp)
	356	VOP_UNLOCK(vp, 0, p);
	357	out2:
	358	vput(tdvp);
	359	return (error);
	360	}