[GitHub/mt8127/android_kernel_alcatel_ttab.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;
	boolean_t	call_again = B_FALSE;
	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, &call_again, &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 (!call_again && (ip == NULL)) {
		*ipp = NULL;
		return XFS_ERROR(ENOSPC);
	}

	/*
	 * If call_again is set, 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 (call_again) {

		/*
		 * 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, &call_again, &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 ((!call_again) && (ip != NULL));

	} 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;
	68	boolean_t call_again = B_FALSE;
	69	int code;
	70	uint log_res;
	71	uint log_count;
	72	void *dqinfo;
	73	uint tflags;
	74
	75	tp = *tpp;
	76	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
	77
	78	/*
	79	* xfs_ialloc will return a pointer to an incore inode if
	80	* the Space Manager has an available inode on the free
	81	* list. Otherwise, it will do an allocation and replenish
	82	* the freelist. Since we can only do one allocation per
	83	* transaction without deadlocks, we will need to commit the
	84	* current transaction and start a new one. We will then
	85	* need to call xfs_ialloc again to get the inode.
	86	*
	87	* If xfs_ialloc did an allocation to replenish the freelist,
	88	* it returns the bp containing the head of the freelist as
	89	* ialloc_context. We will hold a lock on it across the
	90	* transaction commit so that no other process can steal
	91	* the inode(s) that we've just allocated.
	92	*/
6c77b0ea	93	code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, okalloc,
1da177e4 LT	94	&ialloc_context, &call_again, &ip);
	95
	96	/*
	97	* Return an error if we were unable to allocate a new inode.
	98	* This should only happen if we run out of space on disk or
	99	* encounter a disk error.
	100	*/
	101	if (code) {
	102	*ipp = NULL;
	103	return code;
	104	}
	105	if (!call_again && (ip == NULL)) {
	106	*ipp = NULL;
	107	return XFS_ERROR(ENOSPC);
	108	}
	109
	110	/*
	111	* If call_again is set, then we were unable to get an
	112	* inode in one operation. We need to commit the current
	113	* transaction and call xfs_ialloc() again. It is guaranteed
	114	* to succeed the second time.
	115	*/
	116	if (call_again) {
	117
	118	/*
	119	* Normally, xfs_trans_commit releases all the locks.
	120	* We call bhold to hang on to the ialloc_context across
	121	* the commit. Holding this buffer prevents any other
	122	* processes from doing any allocations in this
	123	* allocation group.
	124	*/
	125	xfs_trans_bhold(tp, ialloc_context);
	126	/*
	127	* Save the log reservation so we can use
	128	* them in the next transaction.
	129	*/
	130	log_res = xfs_trans_get_log_res(tp);
	131	log_count = xfs_trans_get_log_count(tp);
	132
	133	/*
	134	* We want the quota changes to be associated with the next
	135	* transaction, NOT this one. So, detach the dqinfo from this
	136	* and attach it to the next transaction.
	137	*/
	138	dqinfo = NULL;
	139	tflags = 0;
	140	if (tp->t_dqinfo) {
	141	dqinfo = (void *)tp->t_dqinfo;
	142	tp->t_dqinfo = NULL;
	143	tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
	144	tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
	145	}
	146
	147	ntp = xfs_trans_dup(tp);
1c72bf90	148	code = xfs_trans_commit(tp, 0);
1da177e4 LT	149	tp = ntp;
	150	if (committed != NULL) {
	151	*committed = 1;
	152	}
	153	/*
	154	* If we get an error during the commit processing,
	155	* release the buffer that is still held and return
	156	* to the caller.
	157	*/
	158	if (code) {
	159	xfs_buf_relse(ialloc_context);
	160	if (dqinfo) {
	161	tp->t_dqinfo = dqinfo;
7d095257	162	xfs_trans_free_dqinfo(tp);
1da177e4 LT	163	}
	164	*tpp = ntp;
	165	*ipp = NULL;
	166	return code;
	167	}
cc09c0dc DC	168
	169	/*
	170	* transaction commit worked ok so we can drop the extra ticket
	171	* reference that we gained in xfs_trans_dup()
	172	*/
	173	xfs_log_ticket_put(tp->t_ticket);
1da177e4 LT	174	code = xfs_trans_reserve(tp, 0, log_res, 0,
	175	XFS_TRANS_PERM_LOG_RES, log_count);
	176	/*
	177	* Re-attach the quota info that we detached from prev trx.
	178	*/
	179	if (dqinfo) {
	180	tp->t_dqinfo = dqinfo;
	181	tp->t_flags \|= tflags;
	182	}
	183
	184	if (code) {
	185	xfs_buf_relse(ialloc_context);
	186	*tpp = ntp;
	187	*ipp = NULL;
	188	return code;
	189	}
	190	xfs_trans_bjoin(tp, ialloc_context);
	191
	192	/*
	193	* Call ialloc again. Since we've locked out all
	194	* other allocations in this allocation group,
	195	* this call should always succeed.
	196	*/
6c77b0ea	197	code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
1da177e4 LT	198	okalloc, &ialloc_context, &call_again, &ip);
	199
	200	/*
	201	* If we get an error at this point, return to the caller
	202	* so that the current transaction can be aborted.
	203	*/
	204	if (code) {
	205	*tpp = tp;
	206	*ipp = NULL;
	207	return code;
	208	}
	209	ASSERT ((!call_again) && (ip != NULL));
	210
	211	} else {
	212	if (committed != NULL) {
	213	*committed = 0;
	214	}
	215	}
	216
	217	*ipp = ip;
	218	*tpp = tp;
	219
	220	return 0;
	221	}
	222
	223	/*
	224	* Decrement the link count on an inode & log the change.
	225	* If this causes the link count to go to zero, initiate the
	226	* logging activity required to truncate a file.
	227	*/
	228	int /* error */
	229	xfs_droplink(
	230	xfs_trans_t *tp,
	231	xfs_inode_t *ip)
	232	{
	233	int error;
	234
dcd79a14	235	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1da177e4 LT	236
	237	ASSERT (ip->i_d.di_nlink > 0);
	238	ip->i_d.di_nlink--;
01651646	239	drop_nlink(VFS_I(ip));
1da177e4 LT	240	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
	241
	242	error = 0;
	243	if (ip->i_d.di_nlink == 0) {
	244	/*
	245	* We're dropping the last link to this file.
	246	* Move the on-disk inode to the AGI unlinked list.
	247	* From xfs_inactive() we will pull the inode from
	248	* the list and free it.
	249	*/
	250	error = xfs_iunlink(tp, ip);
	251	}
	252	return error;
	253	}
	254
	255	/*
	256	* This gets called when the inode's version needs to be changed from 1 to 2.
	257	* Currently this happens when the nlink field overflows the old 16-bit value
	258	* or when chproj is called to change the project for the first time.
	259	* As a side effect the superblock version will also get rev'd
	260	* to contain the NLINK bit.
	261	*/
	262	void
	263	xfs_bump_ino_vers2(
	264	xfs_trans_t *tp,
	265	xfs_inode_t *ip)
	266	{
	267	xfs_mount_t *mp;
1da177e4	268
579aa9ca	269	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
51ce16d5	270	ASSERT(ip->i_d.di_version == 1);
1da177e4	271
51ce16d5	272	ip->i_d.di_version = 2;
1da177e4 LT	273	ip->i_d.di_onlink = 0;
	274	memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
	275	mp = tp->t_mountp;
62118709	276	if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
3685c2a1	277	spin_lock(&mp->m_sb_lock);
62118709 ES	278	if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
62118709 ES	279	xfs_sb_version_addnlink(&mp->m_sb);
3685c2a1	280	spin_unlock(&mp->m_sb_lock);
1da177e4 LT	281	xfs_mod_sb(tp, XFS_SB_VERSIONNUM);
1da177e4 LT	282	} else {
3685c2a1	283	spin_unlock(&mp->m_sb_lock);
1da177e4 LT	284	}
	285	}
	286	/* Caller must log the inode */
	287	}
	288
	289	/*
	290	* Increment the link count on an inode & log the change.
	291	*/
	292	int
	293	xfs_bumplink(
	294	xfs_trans_t *tp,
	295	xfs_inode_t *ip)
	296	{
dcd79a14	297	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1da177e4 LT	298
	299	ASSERT(ip->i_d.di_nlink > 0);
	300	ip->i_d.di_nlink++;
01651646	301	inc_nlink(VFS_I(ip));
51ce16d5	302	if ((ip->i_d.di_version == 1) &&
1da177e4 LT	303	(ip->i_d.di_nlink > XFS_MAXLINK_1)) {
	304	/*
	305	* The inode has increased its number of links beyond
	306	* what can fit in an old format inode. It now needs
	307	* to be converted to a version 2 inode with a 32 bit
	308	* link count. If this is the first inode in the file
	309	* system to do this, then we need to bump the superblock
	310	* version number as well.
	311	*/
	312	xfs_bump_ino_vers2(tp, ip);
	313	}
	314
	315	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
	316	return 0;
	317	}