[linux.git] / fs / xfs / xfs_utils.c

/*
 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * 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.
 *
 * This program is distributed in the hope that it would 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 the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_inode_item.h"
#include "xfs_bmap.h"
#include "xfs_error.h"
#include "xfs_quota.h"
#include "xfs_itable.h"
#include "xfs_utils.h"


/*
 * Allocates a new inode from disk and return a pointer to the
 * incore copy. This routine will internally commit the current
 * transaction and allocate a new one if the Space Manager needed
 * to do an allocation to replenish the inode free-list.
 *
 * This routine is designed to be called from xfs_create and
 * xfs_create_dir.
 *
 */
int
xfs_dir_ialloc(
	xfs_trans_t	**tpp,		/* input: current transaction;
					   output: may be a new transaction. */
	xfs_inode_t	*dp,		/* directory within whose allocate
					   the inode. */
	umode_t		mode,
	xfs_nlink_t	nlink,
	xfs_dev_t	rdev,
	prid_t		prid,		/* project id */
	int		okalloc,	/* ok to allocate new space */
	xfs_inode_t	**ipp,		/* pointer to inode; it will be
					   locked. */
	int		*committed)

{
	xfs_trans_t	*tp;
	xfs_trans_t	*ntp;
	xfs_inode_t	*ip;
	xfs_buf_t	*ialloc_context = NULL;
	int		code;
	uint		log_res;
	uint		log_count;
	void		*dqinfo;
	uint		tflags;

	tp = *tpp;
	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);

	/*
	 * xfs_ialloc will return a pointer to an incore inode if
	 * the Space Manager has an available inode on the free
	 * list. Otherwise, it will do an allocation and replenish
	 * the freelist.  Since we can only do one allocation per
	 * transaction without deadlocks, we will need to commit the
	 * current transaction and start a new one.  We will then
	 * need to call xfs_ialloc again to get the inode.
	 *
	 * If xfs_ialloc did an allocation to replenish the freelist,
	 * it returns the bp containing the head of the freelist as
	 * ialloc_context. We will hold a lock on it across the
	 * transaction commit so that no other process can steal
	 * the inode(s) that we've just allocated.
	 */
	code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, okalloc,
			  &ialloc_context, &ip);

	/*
	 * Return an error if we were unable to allocate a new inode.
	 * This should only happen if we run out of space on disk or
	 * encounter a disk error.
	 */
	if (code) {
		*ipp = NULL;
		return code;
	}
	if (!ialloc_context && !ip) {
		*ipp = NULL;
		return XFS_ERROR(ENOSPC);
	}

	/*
	 * If the AGI buffer is non-NULL, then we were unable to get an
	 * inode in one operation.  We need to commit the current
	 * transaction and call xfs_ialloc() again.  It is guaranteed
	 * to succeed the second time.
	 */
	if (ialloc_context) {
		/*
		 * Normally, xfs_trans_commit releases all the locks.
		 * We call bhold to hang on to the ialloc_context across
		 * the commit.  Holding this buffer prevents any other
		 * processes from doing any allocations in this
		 * allocation group.
		 */
		xfs_trans_bhold(tp, ialloc_context);
		/*
		 * Save the log reservation so we can use
		 * them in the next transaction.
		 */
		log_res = xfs_trans_get_log_res(tp);
		log_count = xfs_trans_get_log_count(tp);

		/*
		 * We want the quota changes to be associated with the next
		 * transaction, NOT this one. So, detach the dqinfo from this
		 * and attach it to the next transaction.
		 */
		dqinfo = NULL;
		tflags = 0;
		if (tp->t_dqinfo) {
			dqinfo = (void *)tp->t_dqinfo;
			tp->t_dqinfo = NULL;
			tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
			tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
		}

		ntp = xfs_trans_dup(tp);
		code = xfs_trans_commit(tp, 0);
		tp = ntp;
		if (committed != NULL) {
			*committed = 1;
		}
		/*
		 * If we get an error during the commit processing,
		 * release the buffer that is still held and return
		 * to the caller.
		 */
		if (code) {
			xfs_buf_relse(ialloc_context);
			if (dqinfo) {
				tp->t_dqinfo = dqinfo;
				xfs_trans_free_dqinfo(tp);
			}
			*tpp = ntp;
			*ipp = NULL;
			return code;
		}

		/*
		 * transaction commit worked ok so we can drop the extra ticket
		 * reference that we gained in xfs_trans_dup()
		 */
		xfs_log_ticket_put(tp->t_ticket);
		code = xfs_trans_reserve(tp, 0, log_res, 0,
					 XFS_TRANS_PERM_LOG_RES, log_count);
		/*
		 * Re-attach the quota info that we detached from prev trx.
		 */
		if (dqinfo) {
			tp->t_dqinfo = dqinfo;
			tp->t_flags |= tflags;
		}

		if (code) {
			xfs_buf_relse(ialloc_context);
			*tpp = ntp;
			*ipp = NULL;
			return code;
		}
		xfs_trans_bjoin(tp, ialloc_context);

		/*
		 * Call ialloc again. Since we've locked out all
		 * other allocations in this allocation group,
		 * this call should always succeed.
		 */
		code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
				  okalloc, &ialloc_context, &ip);

		/*
		 * If we get an error at this point, return to the caller
		 * so that the current transaction can be aborted.
		 */
		if (code) {
			*tpp = tp;
			*ipp = NULL;
			return code;
		}
		ASSERT(!ialloc_context && ip);

	} else {
		if (committed != NULL)
			*committed = 0;
	}

	*ipp = ip;
	*tpp = tp;

	return 0;
}

/*
 * Decrement the link count on an inode & log the change.
 * If this causes the link count to go to zero, initiate the
 * logging activity required to truncate a file.
 */
int				/* error */
xfs_droplink(
	xfs_trans_t *tp,
	xfs_inode_t *ip)
{
	int	error;

	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);

	ASSERT (ip->i_d.di_nlink > 0);
	ip->i_d.di_nlink--;
	drop_nlink(VFS_I(ip));
	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);

	error = 0;
	if (ip->i_d.di_nlink == 0) {
		/*
		 * We're dropping the last link to this file.
		 * Move the on-disk inode to the AGI unlinked list.
		 * From xfs_inactive() we will pull the inode from
		 * the list and free it.
		 */
		error = xfs_iunlink(tp, ip);
	}
	return error;
}

/*
 * This gets called when the inode's version needs to be changed from 1 to 2.
 * Currently this happens when the nlink field overflows the old 16-bit value
 * or when chproj is called to change the project for the first time.
 * As a side effect the superblock version will also get rev'd
 * to contain the NLINK bit.
 */
void
xfs_bump_ino_vers2(
	xfs_trans_t	*tp,
	xfs_inode_t	*ip)
{
	xfs_mount_t	*mp;

	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
	ASSERT(ip->i_d.di_version == 1);

	ip->i_d.di_version = 2;
	ip->i_d.di_onlink = 0;
	memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
	mp = tp->t_mountp;
	if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
		spin_lock(&mp->m_sb_lock);
		if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
			xfs_sb_version_addnlink(&mp->m_sb);
			spin_unlock(&mp->m_sb_lock);
			xfs_mod_sb(tp, XFS_SB_VERSIONNUM);
		} else {
			spin_unlock(&mp->m_sb_lock);
		}
	}
	/* Caller must log the inode */
}

/*
 * Increment the link count on an inode & log the change.
 */
int
xfs_bumplink(
	xfs_trans_t *tp,
	xfs_inode_t *ip)
{
	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);

	ASSERT(ip->i_d.di_nlink > 0);
	ip->i_d.di_nlink++;
	inc_nlink(VFS_I(ip));
	if ((ip->i_d.di_version == 1) &&
	    (ip->i_d.di_nlink > XFS_MAXLINK_1)) {
		/*
		 * The inode has increased its number of links beyond
		 * what can fit in an old format inode.  It now needs
		 * to be converted to a version 2 inode with a 32 bit
		 * link count.  If this is the first inode in the file
		 * system to do this, then we need to bump the superblock
		 * version number as well.
		 */
		xfs_bump_ino_vers2(tp, ip);
	}

	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
	return 0;
}
Commit	Line	Data
1da177e4	1	/*
7b718769 NS	2	* Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
7b718769 NS	3	* All Rights Reserved.
1da177e4	4	*
7b718769 NS	5	* This program is free software; you can redistribute it and/or
7b718769 NS	6	* modify it under the terms of the GNU General Public License as
1da177e4 LT	7	* published by the Free Software Foundation.
1da177e4 LT	8	*
7b718769 NS	9	* This program is distributed in the hope that it would be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
1da177e4	13	*
7b718769 NS	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write the Free Software Foundation,
	16	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
1da177e4	17	*/
1da177e4	18	#include "xfs.h"
a844f451	19	#include "xfs_fs.h"
1da177e4	20	#include "xfs_types.h"
1da177e4 LT	21	#include "xfs_log.h"
	22	#include "xfs_trans.h"
	23	#include "xfs_sb.h"
a844f451	24	#include "xfs_ag.h"
1da177e4	25	#include "xfs_dir2.h"
1da177e4 LT	26	#include "xfs_mount.h"
1da177e4 LT	27	#include "xfs_bmap_btree.h"
1da177e4	28	#include "xfs_dinode.h"
1da177e4	29	#include "xfs_inode.h"
a844f451	30	#include "xfs_inode_item.h"
1da177e4 LT	31	#include "xfs_bmap.h"
	32	#include "xfs_error.h"
	33	#include "xfs_quota.h"
1da177e4 LT	34	#include "xfs_itable.h"
	35	#include "xfs_utils.h"
	36
1da177e4	37
1da177e4 LT	38	/*
	39	* Allocates a new inode from disk and return a pointer to the
	40	* incore copy. This routine will internally commit the current
	41	* transaction and allocate a new one if the Space Manager needed
	42	* to do an allocation to replenish the inode free-list.
	43	*
	44	* This routine is designed to be called from xfs_create and
	45	* xfs_create_dir.
	46	*
	47	*/
	48	int
	49	xfs_dir_ialloc(
	50	xfs_trans_t *tpp, / input: current transaction;
	51	output: may be a new transaction. */
	52	xfs_inode_t dp, / directory within whose allocate
	53	the inode. */
576b1d67	54	umode_t mode,
31b084ae	55	xfs_nlink_t nlink,
1da177e4	56	xfs_dev_t rdev,
1da177e4 LT	57	prid_t prid, /* project id */
	58	int okalloc, /* ok to allocate new space */
	59	xfs_inode_t *ipp, / pointer to inode; it will be
	60	locked. */
	61	int *committed)
	62
	63	{
	64	xfs_trans_t *tp;
	65	xfs_trans_t *ntp;
	66	xfs_inode_t *ip;
	67	xfs_buf_t *ialloc_context = NULL;
1da177e4 LT	68	int code;
	69	uint log_res;
	70	uint log_count;
	71	void *dqinfo;
	72	uint tflags;
	73
	74	tp = *tpp;
	75	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
	76
	77	/*
	78	* xfs_ialloc will return a pointer to an incore inode if
	79	* the Space Manager has an available inode on the free
	80	* list. Otherwise, it will do an allocation and replenish
	81	* the freelist. Since we can only do one allocation per
	82	* transaction without deadlocks, we will need to commit the
	83	* current transaction and start a new one. We will then
	84	* need to call xfs_ialloc again to get the inode.
	85	*
	86	* If xfs_ialloc did an allocation to replenish the freelist,
	87	* it returns the bp containing the head of the freelist as
	88	* ialloc_context. We will hold a lock on it across the
	89	* transaction commit so that no other process can steal
	90	* the inode(s) that we've just allocated.
	91	*/
6c77b0ea	92	code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, okalloc,
08358906	93	&ialloc_context, &ip);
1da177e4 LT	94
	95	/*
	96	* Return an error if we were unable to allocate a new inode.
	97	* This should only happen if we run out of space on disk or
	98	* encounter a disk error.
	99	*/
	100	if (code) {
	101	*ipp = NULL;
	102	return code;
	103	}
08358906	104	if (!ialloc_context && !ip) {
1da177e4 LT	105	*ipp = NULL;
	106	return XFS_ERROR(ENOSPC);
	107	}
	108
	109	/*
08358906	110	* If the AGI buffer is non-NULL, then we were unable to get an
1da177e4 LT	111	* inode in one operation. We need to commit the current
	112	* transaction and call xfs_ialloc() again. It is guaranteed
	113	* to succeed the second time.
	114	*/
08358906	115	if (ialloc_context) {
1da177e4 LT	116	/*
	117	* Normally, xfs_trans_commit releases all the locks.
	118	* We call bhold to hang on to the ialloc_context across
	119	* the commit. Holding this buffer prevents any other
	120	* processes from doing any allocations in this
	121	* allocation group.
	122	*/
	123	xfs_trans_bhold(tp, ialloc_context);
	124	/*
	125	* Save the log reservation so we can use
	126	* them in the next transaction.
	127	*/
	128	log_res = xfs_trans_get_log_res(tp);
	129	log_count = xfs_trans_get_log_count(tp);
	130
	131	/*
	132	* We want the quota changes to be associated with the next
	133	* transaction, NOT this one. So, detach the dqinfo from this
	134	* and attach it to the next transaction.
	135	*/
	136	dqinfo = NULL;
	137	tflags = 0;
	138	if (tp->t_dqinfo) {
	139	dqinfo = (void *)tp->t_dqinfo;
	140	tp->t_dqinfo = NULL;
	141	tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
	142	tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
	143	}
	144
	145	ntp = xfs_trans_dup(tp);
1c72bf90	146	code = xfs_trans_commit(tp, 0);
1da177e4 LT	147	tp = ntp;
	148	if (committed != NULL) {
	149	*committed = 1;
	150	}
	151	/*
	152	* If we get an error during the commit processing,
	153	* release the buffer that is still held and return
	154	* to the caller.
	155	*/
	156	if (code) {
	157	xfs_buf_relse(ialloc_context);
	158	if (dqinfo) {
	159	tp->t_dqinfo = dqinfo;
7d095257	160	xfs_trans_free_dqinfo(tp);
1da177e4 LT	161	}
	162	*tpp = ntp;
	163	*ipp = NULL;
	164	return code;
	165	}
cc09c0dc DC	166
	167	/*
	168	* transaction commit worked ok so we can drop the extra ticket
	169	* reference that we gained in xfs_trans_dup()
	170	*/
	171	xfs_log_ticket_put(tp->t_ticket);
1da177e4 LT	172	code = xfs_trans_reserve(tp, 0, log_res, 0,
	173	XFS_TRANS_PERM_LOG_RES, log_count);
	174	/*
	175	* Re-attach the quota info that we detached from prev trx.
	176	*/
	177	if (dqinfo) {
	178	tp->t_dqinfo = dqinfo;
	179	tp->t_flags \|= tflags;
	180	}
	181
	182	if (code) {
	183	xfs_buf_relse(ialloc_context);
	184	*tpp = ntp;
	185	*ipp = NULL;
	186	return code;
	187	}
	188	xfs_trans_bjoin(tp, ialloc_context);
	189
	190	/*
	191	* Call ialloc again. Since we've locked out all
	192	* other allocations in this allocation group,
	193	* this call should always succeed.
	194	*/
6c77b0ea	195	code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
08358906	196	okalloc, &ialloc_context, &ip);
1da177e4 LT	197
	198	/*
	199	* If we get an error at this point, return to the caller
	200	* so that the current transaction can be aborted.
	201	*/
	202	if (code) {
	203	*tpp = tp;
	204	*ipp = NULL;
	205	return code;
	206	}
08358906	207	ASSERT(!ialloc_context && ip);
1da177e4 LT	208
1da177e4 LT	209	} else {
08358906	210	if (committed != NULL)
1da177e4	211	*committed = 0;
1da177e4 LT	212	}
	213
	214	*ipp = ip;
	215	*tpp = tp;
	216
	217	return 0;
	218	}
	219
	220	/*
	221	* Decrement the link count on an inode & log the change.
	222	* If this causes the link count to go to zero, initiate the
	223	* logging activity required to truncate a file.
	224	*/
	225	int /* error */
	226	xfs_droplink(
	227	xfs_trans_t *tp,
	228	xfs_inode_t *ip)
	229	{
	230	int error;
	231
dcd79a14	232	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1da177e4 LT	233
	234	ASSERT (ip->i_d.di_nlink > 0);
	235	ip->i_d.di_nlink--;
01651646	236	drop_nlink(VFS_I(ip));
1da177e4 LT	237	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
	238
	239	error = 0;
	240	if (ip->i_d.di_nlink == 0) {
	241	/*
	242	* We're dropping the last link to this file.
	243	* Move the on-disk inode to the AGI unlinked list.
	244	* From xfs_inactive() we will pull the inode from
	245	* the list and free it.
	246	*/
	247	error = xfs_iunlink(tp, ip);
	248	}
	249	return error;
	250	}
	251
	252	/*
	253	* This gets called when the inode's version needs to be changed from 1 to 2.
	254	* Currently this happens when the nlink field overflows the old 16-bit value
	255	* or when chproj is called to change the project for the first time.
	256	* As a side effect the superblock version will also get rev'd
	257	* to contain the NLINK bit.
	258	*/
	259	void
	260	xfs_bump_ino_vers2(
	261	xfs_trans_t *tp,
	262	xfs_inode_t *ip)
	263	{
	264	xfs_mount_t *mp;
1da177e4	265
579aa9ca	266	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
51ce16d5	267	ASSERT(ip->i_d.di_version == 1);
1da177e4	268
51ce16d5	269	ip->i_d.di_version = 2;
1da177e4 LT	270	ip->i_d.di_onlink = 0;
	271	memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
	272	mp = tp->t_mountp;
62118709	273	if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
3685c2a1	274	spin_lock(&mp->m_sb_lock);
62118709 ES	275	if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
62118709 ES	276	xfs_sb_version_addnlink(&mp->m_sb);
3685c2a1	277	spin_unlock(&mp->m_sb_lock);
1da177e4 LT	278	xfs_mod_sb(tp, XFS_SB_VERSIONNUM);
1da177e4 LT	279	} else {
3685c2a1	280	spin_unlock(&mp->m_sb_lock);
1da177e4 LT	281	}
	282	}
	283	/* Caller must log the inode */
	284	}
	285
	286	/*
	287	* Increment the link count on an inode & log the change.
	288	*/
	289	int
	290	xfs_bumplink(
	291	xfs_trans_t *tp,
	292	xfs_inode_t *ip)
	293	{
dcd79a14	294	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1da177e4 LT	295
	296	ASSERT(ip->i_d.di_nlink > 0);
	297	ip->i_d.di_nlink++;
01651646	298	inc_nlink(VFS_I(ip));
51ce16d5	299	if ((ip->i_d.di_version == 1) &&
1da177e4 LT	300	(ip->i_d.di_nlink > XFS_MAXLINK_1)) {
	301	/*
	302	* The inode has increased its number of links beyond
	303	* what can fit in an old format inode. It now needs
	304	* to be converted to a version 2 inode with a 32 bit
	305	* link count. If this is the first inode in the file
	306	* system to do this, then we need to bump the superblock
	307	* version number as well.
	308	*/
	309	xfs_bump_ino_vers2(tp, ip);
	310	}
	311
	312	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
	313	return 0;
	314	}