[dragonfly.git] / sys / vfs / hammer2 / hammer2_inode.c

/*
 * Copyright (c) 2011-2012 The DragonFly Project.  All rights reserved.
 *
 * This code is derived from software contributed to The DragonFly Project
 * by Matthew Dillon <dillon@dragonflybsd.org>
 * by Venkatesh Srinivas <vsrinivas@dragonflybsd.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name of The DragonFly Project nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific, prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
#include <sys/cdefs.h>
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/types.h>
#include <sys/lock.h>
#include <sys/uuid.h>

#include "hammer2.h"

/*
 * Adding a ref to an inode is only legal if the inode already has at least
 * one ref.
 */
void
hammer2_inode_ref(hammer2_inode_t *ip)
{
	hammer2_chain_ref(ip->hmp, &ip->chain);
}

/*
 * Drop an inode reference, freeing the inode when the last reference goes
 * away.
 */
void
hammer2_inode_drop(hammer2_inode_t *ip)
{
	hammer2_chain_drop(ip->hmp, &ip->chain);
}

/*
 * Get the vnode associated with the given inode, allocating the vnode if
 * necessary.
 *
 * Great care must be taken to avoid deadlocks and vnode acquisition/reclaim
 * races.
 *
 * The vnode will be returned exclusively locked and referenced.  The
 * reference on the vnode prevents it from being reclaimed.
 *
 * The inode (ip) must be referenced by the caller and not locked to avoid
 * it getting ripped out from under us or deadlocked.
 */
struct vnode *
hammer2_igetv(hammer2_inode_t *ip, int *errorp)
{
	struct vnode *vp;
	hammer2_mount_t *hmp;

	hmp = ip->hmp;
	*errorp = 0;

	for (;;) {
		/*
		 * Attempt to reuse an existing vnode assignment.  It is
		 * possible to race a reclaim so the vget() may fail.  The
		 * inode must be unlocked during the vget() to avoid a
		 * deadlock against a reclaim.
		 */
		vp = ip->vp;
		if (vp) {
			/*
			 * Lock the inode and check for a reclaim race
			 */
			hammer2_inode_lock_ex(ip);
			if (ip->vp != vp) {
				hammer2_inode_unlock_ex(ip);
				continue;
			}

			/*
			 * Inode must be unlocked during the vget() to avoid
			 * possible deadlocks, vnode is held to prevent
			 * destruction during the vget().  The vget() can
			 * still fail if we lost a reclaim race on the vnode.
			 */
			vhold_interlocked(vp);
			hammer2_inode_unlock_ex(ip);
			if (vget(vp, LK_EXCLUSIVE)) {
				vdrop(vp);
				continue;
			}
			vdrop(vp);
			/* vp still locked and ref from vget */
			*errorp = 0;
			break;
		}

		/*
		 * No vnode exists, allocate a new vnode.  Beware of
		 * allocation races.  This function will return an
		 * exclusively locked and referenced vnode.
		 */
		*errorp = getnewvnode(VT_HAMMER2, H2TOMP(hmp), &vp, 0, 0);
		if (*errorp) {
			vp = NULL;
			break;
		}

		/*
		 * Lock the inode and check for an allocation race.
		 */
		hammer2_inode_lock_ex(ip);
		if (ip->vp != NULL) {
			vp->v_type = VBAD;
			vx_put(vp);
			hammer2_inode_unlock_ex(ip);
			continue;
		}

		switch (ip->ip_data.type) {
		case HAMMER2_OBJTYPE_DIRECTORY:
			vp->v_type = VDIR;
			break;
		case HAMMER2_OBJTYPE_REGFILE:
			vp->v_type = VREG;
			vinitvmio(vp, 0, HAMMER2_LBUFSIZE,
				  (int)ip->ip_data.size & HAMMER2_LBUFMASK);
			break;
		/* XXX FIFO */
		default:
			panic("hammer2: unhandled objtype %d",
			      ip->ip_data.type);
			break;
		}

		if (ip == hmp->iroot)
			vsetflags(vp, VROOT);

		vp->v_data = ip;
		ip->vp = vp;
		hammer2_chain_ref(hmp, &ip->chain);	/* vp association */
		hammer2_inode_unlock_ex(ip);
		break;
	}

	/*
	 * Return non-NULL vp and *errorp == 0, or NULL vp and *errorp != 0.
	 */
	if (hammer2_debug & 0x0002) {
		kprintf("igetv vp %p refs %d aux %d\n",
			vp, vp->v_sysref.refcnt, vp->v_auxrefs);
	}
	return (vp);
}

/*
 * Create a new inode in the specified directory using the vattr to
 * figure out the type of inode.
 *
 * If no error occurs the new inode with its chain locked is returned in
 * *nipp, otherwise an error is returned and *nipp is set to NULL.
 */
int
hammer2_create_inode(hammer2_mount_t *hmp,
		     struct vattr *vap, struct ucred *cred,
		     hammer2_inode_t *dip,
		     const uint8_t *name, size_t name_len,
		     hammer2_inode_t **nipp)
{
	hammer2_chain_t *chain;
	hammer2_chain_t *parent;
	hammer2_inode_t *nip;
	hammer2_key_t lhc;
	int error;

	lhc = hammer2_dirhash(name, name_len);

	/*
	 * Locate the inode or indirect block to create the new
	 * entry in.  At the same time check for key collisions
	 * and iterate until we don't get one.
	 */
	parent = &dip->chain;
	hammer2_chain_ref(hmp, parent);
	hammer2_chain_lock(hmp, parent);

	error = 0;
	while (error == 0) {
		chain = hammer2_chain_lookup(hmp, &parent, lhc, lhc, 0);
		if (chain == NULL)
			break;
		if ((lhc & HAMMER2_DIRHASH_LOMASK) == HAMMER2_DIRHASH_LOMASK)
			error = ENOSPC;
		hammer2_chain_put(hmp, chain);
		chain = NULL;
		++lhc;
	}
	if (error == 0) {
		chain = hammer2_chain_create(hmp, parent, lhc, 0,
					     HAMMER2_BREF_TYPE_INODE,
					     HAMMER2_INODE_BYTES);
		if (chain == NULL)
			error = EIO;
	}
	hammer2_chain_put(hmp, parent);

	/*
	 * Handle the error case
	 */
	if (error) {
		KKASSERT(chain == NULL);
		*nipp = NULL;
		return (error);
	}

	/*
	 * Set up the new inode
	 */
	nip = chain->u.ip;
	*nipp = nip;

	nip->ip_data.type = hammer2_get_obj_type(vap->va_type);
	nip->ip_data.inum = hmp->voldata.alloc_tid++;	/* XXX modify/lock */
	nip->ip_data.version = HAMMER2_INODE_VERSION_ONE;
	nip->ip_data.ctime = 0;
	nip->ip_data.mtime = 0;
	nip->ip_data.mode = vap->va_mode;
	nip->ip_data.nlinks = 1;
	/* uid, gid, etc */

	KKASSERT(name_len < HAMMER2_INODE_MAXNAME);
	bcopy(name, nip->ip_data.filename, name_len);
	nip->ip_data.name_key = lhc;
	nip->ip_data.name_len = name_len;

	return (0);
}
Commit	Line	Data
7cfa8da5 MD	1	/*
	2	* Copyright (c) 2011-2012 The DragonFly Project. All rights reserved.
	3	*
	4	* This code is derived from software contributed to The DragonFly Project
	5	* by Matthew Dillon <dillon@dragonflybsd.org>
	6	* by Venkatesh Srinivas <vsrinivas@dragonflybsd.org>
	7	*
	8	* Redistribution and use in source and binary forms, with or without
	9	* modification, are permitted provided that the following conditions
	10	* are met:
	11	*
	12	* 1. Redistributions of source code must retain the above copyright
	13	* notice, this list of conditions and the following disclaimer.
	14	* 2. Redistributions in binary form must reproduce the above copyright
	15	* notice, this list of conditions and the following disclaimer in
	16	* the documentation and/or other materials provided with the
	17	* distribution.
	18	* 3. Neither the name of The DragonFly Project nor the names of its
	19	* contributors may be used to endorse or promote products derived
	20	* from this software without specific, prior written permission.
	21	*
	22	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	23	* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	24	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
	25	* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
	26	* COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
	27	* INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
	28	* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	29	* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
	30	* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	31	* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
	32	* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	33	* SUCH DAMAGE.
	34	*/
	35	#include <sys/cdefs.h>
	36	#include <sys/cdefs.h>
	37	#include <sys/param.h>
	38	#include <sys/systm.h>
	39	#include <sys/types.h>
	40	#include <sys/lock.h>
	41	#include <sys/uuid.h>
	42
	43	#include "hammer2.h"
	44
	45	/*
	46	* Adding a ref to an inode is only legal if the inode already has at least
	47	* one ref.
	48	*/
	49	void
	50	hammer2_inode_ref(hammer2_inode_t *ip)
	51	{
5c23d7f1	52	hammer2_chain_ref(ip->hmp, &ip->chain);
7cfa8da5 MD	53	}
	54
	55	/*
	56	* Drop an inode reference, freeing the inode when the last reference goes
	57	* away.
	58	*/
	59	void
	60	hammer2_inode_drop(hammer2_inode_t *ip)
	61	{
5c23d7f1	62	hammer2_chain_drop(ip->hmp, &ip->chain);
7cfa8da5 MD	63	}
	64
	65	/*
	66	* Get the vnode associated with the given inode, allocating the vnode if
	67	* necessary.
	68	*
	69	* Great care must be taken to avoid deadlocks and vnode acquisition/reclaim
	70	* races.
	71	*
	72	* The vnode will be returned exclusively locked and referenced. The
	73	* reference on the vnode prevents it from being reclaimed.
	74	*
	75	* The inode (ip) must be referenced by the caller and not locked to avoid
	76	* it getting ripped out from under us or deadlocked.
	77	*/
	78	struct vnode *
	79	hammer2_igetv(hammer2_inode_t ip, int errorp)
	80	{
	81	struct vnode *vp;
	82	hammer2_mount_t *hmp;
	83
	84	hmp = ip->hmp;
	85	*errorp = 0;
	86
	87	for (;;) {
	88	/*
	89	* Attempt to reuse an existing vnode assignment. It is
	90	* possible to race a reclaim so the vget() may fail. The
	91	* inode must be unlocked during the vget() to avoid a
	92	* deadlock against a reclaim.
	93	*/
	94	vp = ip->vp;
	95	if (vp) {
	96	/*
	97	* Lock the inode and check for a reclaim race
	98	*/
	99	hammer2_inode_lock_ex(ip);
	100	if (ip->vp != vp) {
	101	hammer2_inode_unlock_ex(ip);
	102	continue;
	103	}
	104
	105	/*
	106	* Inode must be unlocked during the vget() to avoid
	107	* possible deadlocks, vnode is held to prevent
	108	* destruction during the vget(). The vget() can
	109	* still fail if we lost a reclaim race on the vnode.
	110	*/
	111	vhold_interlocked(vp);
	112	hammer2_inode_unlock_ex(ip);
	113	if (vget(vp, LK_EXCLUSIVE)) {
	114	vdrop(vp);
	115	continue;
	116	}
	117	vdrop(vp);
	118	/* vp still locked and ref from vget */
	119	*errorp = 0;
	120	break;
	121	}
	122
	123	/*
	124	* No vnode exists, allocate a new vnode. Beware of
	125	* allocation races. This function will return an
	126	* exclusively locked and referenced vnode.
127	*/
128	*errorp = getnewvnode(VT_HAMMER2, H2TOMP(hmp), &vp, 0, 0);
129	if (*errorp) {
130	vp = NULL;
131	break;
132	}
133
134	/*
135	* Lock the inode and check for an allocation race.
136	*/
137	hammer2_inode_lock_ex(ip);
138	if (ip->vp != NULL) {
139	vp->v_type = VBAD;
140	vx_put(vp);
141	hammer2_inode_unlock_ex(ip);
142	continue;
143	}
144
5c23d7f1	145	switch (ip->ip_data.type) {
df9ea374	146	case HAMMER2_OBJTYPE_DIRECTORY:
7cfa8da5 MD	147	vp->v_type = VDIR;
7cfa8da5 MD	148	break;
df9ea374	149	case HAMMER2_OBJTYPE_REGFILE:
7cfa8da5 MD	150	vp->v_type = VREG;
7cfa8da5 MD	151	vinitvmio(vp, 0, HAMMER2_LBUFSIZE,
5c23d7f1	152	(int)ip->ip_data.size & HAMMER2_LBUFMASK);
7cfa8da5 MD	153	break;
	154	/* XXX FIFO */
	155	default:
5c23d7f1 MD	156	panic("hammer2: unhandled objtype %d",
5c23d7f1 MD	157	ip->ip_data.type);
7cfa8da5 MD	158	break;
	159	}
	160
df9ea374	161	if (ip == hmp->iroot)
7cfa8da5 MD	162	vsetflags(vp, VROOT);
	163
	164	vp->v_data = ip;
	165	ip->vp = vp;
9c2e0de0	166	hammer2_chain_ref(hmp, &ip->chain); /* vp association */
7cfa8da5 MD	167	hammer2_inode_unlock_ex(ip);
	168	break;
	169	}
	170
	171	/*
	172	* Return non-NULL vp and errorp == 0, or NULL vp and errorp != 0.
	173	*/
37aa19df MD	174	if (hammer2_debug & 0x0002) {
	175	kprintf("igetv vp %p refs %d aux %d\n",
	176	vp, vp->v_sysref.refcnt, vp->v_auxrefs);
	177	}
7cfa8da5 MD	178	return (vp);
	179	}
	180
	181	/*
37494cab MD	182	* Create a new inode in the specified directory using the vattr to
37494cab MD	183	* figure out the type of inode.
7cfa8da5	184	*
db71f61f MD	185	* If no error occurs the new inode with its chain locked is returned in
db71f61f MD	186	* nipp, otherwise an error is returned and nipp is set to NULL.
7cfa8da5	187	*/
37494cab MD	188	int
	189	hammer2_create_inode(hammer2_mount_t *hmp,
	190	struct vattr vap, struct ucred cred,
	191	hammer2_inode_t *dip,
	192	const uint8_t *name, size_t name_len,
	193	hammer2_inode_t **nipp)
7cfa8da5	194	{
37494cab MD	195	hammer2_chain_t *chain;
	196	hammer2_chain_t *parent;
	197	hammer2_inode_t *nip;
	198	hammer2_key_t lhc;
	199	int error;
7cfa8da5	200
37494cab	201	lhc = hammer2_dirhash(name, name_len);
7cfa8da5	202
37494cab MD	203	/*
	204	* Locate the inode or indirect block to create the new
	205	* entry in. At the same time check for key collisions
	206	* and iterate until we don't get one.
	207	*/
	208	parent = &dip->chain;
	209	hammer2_chain_ref(hmp, parent);
	210	hammer2_chain_lock(hmp, parent);
7cfa8da5	211
37494cab MD	212	error = 0;
37494cab MD	213	while (error == 0) {
c667909f	214	chain = hammer2_chain_lookup(hmp, &parent, lhc, lhc, 0);
37494cab MD	215	if (chain == NULL)
	216	break;
	217	if ((lhc & HAMMER2_DIRHASH_LOMASK) == HAMMER2_DIRHASH_LOMASK)
	218	error = ENOSPC;
	219	hammer2_chain_put(hmp, chain);
	220	chain = NULL;
	221	++lhc;
	222	}
	223	if (error == 0) {
37aa19df	224	chain = hammer2_chain_create(hmp, parent, lhc, 0,
37494cab MD	225	HAMMER2_BREF_TYPE_INODE,
	226	HAMMER2_INODE_BYTES);
	227	if (chain == NULL)
	228	error = EIO;
	229	}
	230	hammer2_chain_put(hmp, parent);
7cfa8da5	231
37494cab MD	232	/*
	233	* Handle the error case
	234	*/
	235	if (error) {
	236	KKASSERT(chain == NULL);
	237	*nipp = NULL;
	238	return (error);
	239	}
7cfa8da5	240
37494cab MD	241	/*
	242	* Set up the new inode
	243	*/
	244	nip = chain->u.ip;
	245	*nipp = nip;
7cfa8da5	246
37494cab MD	247	nip->ip_data.type = hammer2_get_obj_type(vap->va_type);
	248	nip->ip_data.inum = hmp->voldata.alloc_tid++; /* XXX modify/lock */
	249	nip->ip_data.version = HAMMER2_INODE_VERSION_ONE;
	250	nip->ip_data.ctime = 0;
	251	nip->ip_data.mtime = 0;
	252	nip->ip_data.mode = vap->va_mode;
	253	nip->ip_data.nlinks = 1;
	254	/* uid, gid, etc */
232a50f9	255
37494cab MD	256	KKASSERT(name_len < HAMMER2_INODE_MAXNAME);
	257	bcopy(name, nip->ip_data.filename, name_len);
	258	nip->ip_data.name_key = lhc;
	259	nip->ip_data.name_len = name_len;
7cfa8da5	260
37494cab	261	return (0);
7cfa8da5	262	}