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DEFINITIONS
This source file includes following definitions.
- xfs_dir_ialloc
- xfs_droplink
- xfs_bump_ino_vers2
- xfs_bumplink
- xfs_truncate_file
/*
* 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_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.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_rw.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. */
mode_t mode,
xfs_nlink_t nlink,
xfs_dev_t rdev,
cred_t *credp,
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, credp, 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->t_mountp, tp);
}
*tpp = ntp;
*ipp = NULL;
return code;
}
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, credp, 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_ichgtime(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 == XFS_DINODE_VERSION_1);
ip->i_d.di_version = XFS_DINODE_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)
{
if (ip->i_d.di_nlink >= XFS_MAXLINK)
return XFS_ERROR(EMLINK);
xfs_ichgtime(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 == XFS_DINODE_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;
}
/*
* Try to truncate the given file to 0 length. Currently called
* only out of xfs_remove when it has to truncate a file to free
* up space for the remove to proceed.
*/
int
xfs_truncate_file(
xfs_mount_t *mp,
xfs_inode_t *ip)
{
xfs_trans_t *tp;
int error;
#ifdef QUOTADEBUG
/*
* This is called to truncate the quotainodes too.
*/
if (XFS_IS_UQUOTA_ON(mp)) {
if (ip->i_ino != mp->m_sb.sb_uquotino)
ASSERT(ip->i_udquot);
}
if (XFS_IS_OQUOTA_ON(mp)) {
if (ip->i_ino != mp->m_sb.sb_gquotino)
ASSERT(ip->i_gdquot);
}
#endif
/*
* Make the call to xfs_itruncate_start before starting the
* transaction, because we cannot make the call while we're
* in a transaction.
*/
xfs_ilock(ip, XFS_IOLOCK_EXCL);
error = xfs_itruncate_start(ip, XFS_ITRUNC_DEFINITE, (xfs_fsize_t)0);
if (error) {
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return error;
}
tp = xfs_trans_alloc(mp, XFS_TRANS_TRUNCATE_FILE);
if ((error = xfs_trans_reserve(tp, 0, XFS_ITRUNCATE_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES,
XFS_ITRUNCATE_LOG_COUNT))) {
xfs_trans_cancel(tp, 0);
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return error;
}
/*
* Follow the normal truncate locking protocol. Since we
* hold the inode in the transaction, we know that it's number
* of references will stay constant.
*/
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
xfs_trans_ihold(tp, ip);
/*
* Signal a sync xaction. The only case where that isn't
* the case is if we're truncating an already unlinked file
* on a wsync fs. In that case, we know the blocks can't
* reappear in the file because the links to file are
* permanently toast. Currently, we're always going to
* want a sync transaction because this code is being
* called from places where nlink is guaranteed to be 1
* but I'm leaving the tests in to protect against future
* changes -- rcc.
*/
error = xfs_itruncate_finish(&tp, ip, (xfs_fsize_t)0,
XFS_DATA_FORK,
((ip->i_d.di_nlink != 0 ||
!(mp->m_flags & XFS_MOUNT_WSYNC))
? 1 : 0));
if (error) {
xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES |
XFS_TRANS_ABORT);
} else {
xfs_ichgtime(ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
}
xfs_iunlock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
return error;
}