File: [Development] / xfs-linux / xfs_iomap.c (download)
Revision 1.2, Mon Dec 2 01:18:39 2002 UTC (14 years, 10 months ago) by nathans
Branch: MAIN
Changes since 1.1: +36 -31
lines
Cleanup after initially investigating unwritten extents.
Fix several incorrect comments, make declarations consistent.
|
/*
* Copyright (c) 2000-2002 Silicon Graphics, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 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.
*
* Further, this software is distributed without any warranty that it is
* free of the rightful claim of any third person regarding infringement
* or the like. Any license provided herein, whether implied or
* otherwise, applies only to this software file. Patent licenses, if
* any, provided herein do not apply to combinations of this program with
* other software, or any other product whatsoever.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
* Mountain View, CA 94043, or:
*
* http://www.sgi.com
*
* For further information regarding this notice, see:
*
* http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
*/
/*
* fs/xfs/linux/xfs_lrw.c (Linux Read Write stuff)
*
*/
#include <xfs.h>
#include <linux/pagemap.h>
#include <linux/capability.h>
#define XFS_WRITEIO_ALIGN(mp,off) (((off) >> mp->m_writeio_log) \
<< mp->m_writeio_log)
#define XFS_STRAT_WRITE_IMAPS 2
STATIC int xfs_iomap_read(xfs_iocore_t *, loff_t, size_t, int, page_buf_bmap_t *,
int *);
STATIC int xfs_iomap_write(xfs_iocore_t *, loff_t, size_t, page_buf_bmap_t *,
int *, int);
STATIC int xfs_iomap_write_delay(xfs_iocore_t *, loff_t, size_t, page_buf_bmap_t *,
int *, int, int);
STATIC int xfs_iomap_write_direct(xfs_iocore_t *, loff_t, size_t, page_buf_bmap_t *,
int *, int, int);
STATIC int _xfs_imap_to_bmap(xfs_iocore_t *, xfs_off_t, xfs_bmbt_irec_t *,
page_buf_bmap_t *, int, int);
int
xfs_strategy(
xfs_inode_t *ip,
xfs_off_t offset,
ssize_t count,
int flags,
page_buf_bmap_t *pbmapp,
int *npbmaps)
{
xfs_iocore_t *io;
xfs_mount_t *mp;
int error;
xfs_fileoff_t offset_fsb;
xfs_fileoff_t end_fsb;
xfs_fileoff_t map_start_fsb;
xfs_fileoff_t last_block;
xfs_fsblock_t first_block;
xfs_bmap_free_t free_list;
xfs_filblks_t count_fsb;
int committed, i, loops, nimaps;
int is_xfs;
xfs_bmbt_irec_t imap[XFS_MAX_RW_NBMAPS];
xfs_trans_t *tp;
mp = ip->i_mount;
io = &ip->i_iocore;
is_xfs = IO_IS_XFS(io);
ASSERT((ip->i_d.di_mode & IFMT) == IFREG);
ASSERT(((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) != 0) ==
((io->io_flags & XFS_IOCORE_RT) != 0));
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
offset_fsb = XFS_B_TO_FSBT(mp, offset);
nimaps = min(XFS_MAX_RW_NBMAPS, *npbmaps);
end_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
first_block = NULLFSBLOCK;
XFS_ILOCK(mp, io, XFS_ILOCK_SHARED | XFS_EXTSIZE_RD);
error = XFS_BMAPI(mp, NULL, io, offset_fsb,
(xfs_filblks_t)(end_fsb - offset_fsb),
XFS_BMAPI_ENTIRE, &first_block, 0, imap,
&nimaps, NULL);
XFS_IUNLOCK(mp, io, XFS_ILOCK_SHARED | XFS_EXTSIZE_RD);
if (error) {
return XFS_ERROR(error);
}
if (nimaps && !ISNULLSTARTBLOCK(imap[0].br_startblock)) {
*npbmaps = _xfs_imap_to_bmap(&ip->i_iocore, offset, imap,
pbmapp, nimaps, *npbmaps);
return 0;
}
/*
* Make sure that the dquots are there.
*/
if (XFS_IS_QUOTA_ON(mp)) {
if (XFS_NOT_DQATTACHED(mp, ip)) {
if ((error = xfs_qm_dqattach(ip, 0))) {
return XFS_ERROR(error);
}
}
}
XFS_STATS_ADD(xfsstats.xs_xstrat_bytes,
XFS_FSB_TO_B(mp, imap[0].br_blockcount));
offset_fsb = imap[0].br_startoff;
count_fsb = imap[0].br_blockcount;
map_start_fsb = offset_fsb;
while (count_fsb != 0) {
/*
* Set up a transaction with which to allocate the
* backing store for the file. Do allocations in a
* loop until we get some space in the range we are
* interested in. The other space that might be allocated
* is in the delayed allocation extent on which we sit
* but before our buffer starts.
*/
nimaps = 0;
loops = 0;
while (nimaps == 0) {
if (is_xfs) {
tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
error = xfs_trans_reserve(tp, 0,
XFS_WRITE_LOG_RES(mp),
0, XFS_TRANS_PERM_LOG_RES,
XFS_WRITE_LOG_COUNT);
if (error) {
xfs_trans_cancel(tp, 0);
goto error0;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip,
XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
} else {
tp = NULL;
XFS_ILOCK(mp, io, XFS_ILOCK_EXCL |
XFS_EXTSIZE_WR);
}
/*
* Allocate the backing store for the file.
*/
XFS_BMAP_INIT(&(free_list),
&(first_block));
nimaps = XFS_STRAT_WRITE_IMAPS;
/*
* Ensure we don't go beyond eof - it is possible
* the extents changed since we did the read call,
* we dropped the ilock in the interim.
*/
end_fsb = XFS_B_TO_FSB(mp, XFS_SIZE(mp, io));
xfs_bmap_last_offset(NULL, ip, &last_block,
XFS_DATA_FORK);
last_block = XFS_FILEOFF_MAX(last_block, end_fsb);
if ((map_start_fsb + count_fsb) > last_block) {
count_fsb = last_block - map_start_fsb;
if (count_fsb == 0) {
if (is_xfs) {
xfs_bmap_cancel(&free_list);
xfs_trans_cancel(tp,
(XFS_TRANS_RELEASE_LOG_RES |
XFS_TRANS_ABORT));
}
XFS_IUNLOCK(mp, io, XFS_ILOCK_EXCL |
XFS_EXTSIZE_WR);
return XFS_ERROR(EAGAIN);
}
}
error = XFS_BMAPI(mp, tp, io, map_start_fsb, count_fsb,
XFS_BMAPI_WRITE, &first_block, 1,
imap, &nimaps, &free_list);
if (error) {
xfs_bmap_cancel(&free_list);
xfs_trans_cancel(tp,
(XFS_TRANS_RELEASE_LOG_RES |
XFS_TRANS_ABORT));
XFS_IUNLOCK(mp, io, XFS_ILOCK_EXCL |
XFS_EXTSIZE_WR);
goto error0;
}
if (is_xfs) {
error = xfs_bmap_finish(&(tp), &(free_list),
first_block, &committed);
if (error) {
xfs_bmap_cancel(&free_list);
xfs_trans_cancel(tp,
(XFS_TRANS_RELEASE_LOG_RES |
XFS_TRANS_ABORT));
xfs_iunlock(ip, XFS_ILOCK_EXCL);
goto error0;
}
error = xfs_trans_commit(tp,
XFS_TRANS_RELEASE_LOG_RES,
NULL);
if (error) {
xfs_iunlock(ip, XFS_ILOCK_EXCL);
goto error0;
}
}
if (nimaps == 0) {
XFS_IUNLOCK(mp, io,
XFS_ILOCK_EXCL|XFS_EXTSIZE_WR);
} /* else hold 'till we maybe loop again below */
}
/*
* See if we were able to allocate an extent that
* covers at least part of the user's requested size.
*/
offset_fsb = XFS_B_TO_FSBT(mp, offset);
for (i = 0; i < nimaps; i++) {
int maps;
if ((offset_fsb >= imap[i].br_startoff) &&
(offset_fsb <
(imap[i].br_startoff + imap[i].br_blockcount))) {
XFS_IUNLOCK(mp, io,
XFS_ILOCK_EXCL|XFS_EXTSIZE_WR);
maps = min(nimaps, *npbmaps);
*npbmaps = _xfs_imap_to_bmap(io, offset,
&imap[i], pbmapp,
maps, *npbmaps);
XFS_STATS_INC(xfsstats.xs_xstrat_quick);
return 0;
}
count_fsb -= imap[i].br_blockcount; /* for next bmapi,
if needed. */
}
/*
* We didn't get an extent the caller can write into so
* loop around and try starting after the last imap we got back.
*/
nimaps--; /* Index of last entry */
ASSERT(nimaps >= 0);
ASSERT(offset_fsb >=
imap[nimaps].br_startoff + imap[nimaps].br_blockcount);
ASSERT(count_fsb);
offset_fsb =
imap[nimaps].br_startoff + imap[nimaps].br_blockcount;
map_start_fsb = offset_fsb;
XFS_STATS_INC(xfsstats.xs_xstrat_split);
XFS_IUNLOCK(mp, io, XFS_ILOCK_EXCL|XFS_EXTSIZE_WR);
}
ASSERT(0); /* Should never get here */
error0:
if (error) {
ASSERT(count_fsb != 0);
ASSERT(is_xfs || XFS_FORCED_SHUTDOWN(mp));
}
return XFS_ERROR(error);
}
/*
* xfs_bmap() is the same as the irix xfs_bmap from xfs_rw.c
* execpt for slight changes to the params
*/
int
xfs_bmap(bhv_desc_t *bdp,
xfs_off_t offset,
ssize_t count,
int flags,
page_buf_bmap_t *pbmapp,
int *npbmaps)
{
xfs_inode_t *ip;
int error;
int lockmode;
int fsynced = 0;
vnode_t *vp;
ip = XFS_BHVTOI(bdp);
ASSERT((ip->i_d.di_mode & IFMT) == IFREG);
ASSERT(((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) != 0) ==
((ip->i_iocore.io_flags & XFS_IOCORE_RT) != 0));
if (XFS_FORCED_SHUTDOWN(ip->i_iocore.io_mount))
return XFS_ERROR(EIO);
if (flags & PBF_READ) {
lockmode = xfs_ilock_map_shared(ip);
error = xfs_iomap_read(&ip->i_iocore, offset, count,
XFS_BMAPI_ENTIRE, pbmapp, npbmaps);
xfs_iunlock_map_shared(ip, lockmode);
} else if (flags & PBF_FILE_ALLOCATE) {
error = xfs_strategy(ip, offset, count, flags,
pbmapp, npbmaps);
} else { /* PBF_WRITE */
ASSERT(flags & PBF_WRITE);
vp = BHV_TO_VNODE(bdp);
xfs_ilock(ip, XFS_ILOCK_EXCL);
/*
* Make sure that the dquots are there. This doesn't hold
* the ilock across a disk read.
*/
if (XFS_IS_QUOTA_ON(ip->i_mount)) {
if (XFS_NOT_DQATTACHED(ip->i_mount, ip)) {
if ((error = xfs_qm_dqattach(ip, XFS_QMOPT_ILOCKED))) {
xfs_iunlock(ip, XFS_ILOCK_EXCL);
return XFS_ERROR(error);
}
}
}
retry:
error = xfs_iomap_write(&ip->i_iocore, offset, count,
pbmapp, npbmaps, flags);
/* xfs_iomap_write unlocks/locks/unlocks */
if (error == ENOSPC) {
switch (fsynced) {
case 0:
if (ip->i_delayed_blks) {
fsync_inode_data_buffers(LINVFS_GET_IP(vp));
fsynced = 1;
} else {
fsynced = 2;
flags |= PBF_SYNC;
}
error = 0;
xfs_ilock(ip, XFS_ILOCK_EXCL);
goto retry;
case 1:
fsynced = 2;
if (!(flags & PBF_SYNC)) {
flags |= PBF_SYNC;
error = 0;
xfs_ilock(ip, XFS_ILOCK_EXCL);
goto retry;
}
case 2:
fsync_no_super(LINVFS_GET_IP(vp)->i_dev);
xfs_log_force(ip->i_mount, (xfs_lsn_t)0,
XFS_LOG_FORCE|XFS_LOG_SYNC);
error = 0;
/**
delay(HZ);
**/
fsynced++;
xfs_ilock(ip, XFS_ILOCK_EXCL);
goto retry;
}
}
}
return XFS_ERROR(error);
}
STATIC int
_xfs_imap_to_bmap(
xfs_iocore_t *io,
xfs_off_t offset,
xfs_bmbt_irec_t *imap,
page_buf_bmap_t *pbmapp,
int imaps, /* Number of imap entries */
int pbmaps) /* Number of pbmap entries */
{
xfs_mount_t *mp;
xfs_fsize_t nisize;
int im, pbm;
xfs_fsblock_t start_block;
mp = io->io_mount;
nisize = XFS_SIZE(mp, io);
if (io->io_new_size > nisize)
nisize = io->io_new_size;
for (im=pbm=0; im < imaps && pbm < pbmaps; im++,pbmapp++,imap++,pbm++) {
pbmapp->pbm_target = io->io_flags & XFS_IOCORE_RT ?
mp->m_rtdev_targp : mp->m_ddev_targp;
pbmapp->pbm_offset = XFS_FSB_TO_B(mp, imap->br_startoff);
pbmapp->pbm_delta = offset - pbmapp->pbm_offset;
pbmapp->pbm_bsize = XFS_FSB_TO_B(mp, imap->br_blockcount);
pbmapp->pbm_flags = 0;
start_block = imap->br_startblock;
if (start_block == HOLESTARTBLOCK) {
pbmapp->pbm_bn = PAGE_BUF_DADDR_NULL;
pbmapp->pbm_flags = PBMF_HOLE;
} else if (start_block == DELAYSTARTBLOCK) {
pbmapp->pbm_bn = PAGE_BUF_DADDR_NULL;
pbmapp->pbm_flags = PBMF_DELAY;
} else {
pbmapp->pbm_bn = XFS_FSB_TO_DB_IO(io, start_block);
if (ISUNWRITTEN(imap)) {
pbmapp->pbm_flags |= PBMF_UNWRITTEN;
}
}
if ((pbmapp->pbm_offset + pbmapp->pbm_bsize) >= nisize) {
pbmapp->pbm_flags |= PBMF_EOF;
}
offset += pbmapp->pbm_bsize - pbmapp->pbm_delta;
}
return pbm; /* Return the number filled */
}
STATIC int
xfs_iomap_read(
xfs_iocore_t *io,
loff_t offset,
size_t count,
int flags,
page_buf_bmap_t *pbmapp,
int *npbmaps)
{
xfs_fileoff_t offset_fsb;
xfs_fileoff_t end_fsb;
int nimaps;
int error;
xfs_mount_t *mp;
xfs_bmbt_irec_t imap[XFS_MAX_RW_NBMAPS];
ASSERT(ismrlocked(io->io_lock, MR_UPDATE | MR_ACCESS) != 0);
mp = io->io_mount;
offset_fsb = XFS_B_TO_FSBT(mp, offset);
nimaps = sizeof(imap) / sizeof(imap[0]);
nimaps = min(nimaps, *npbmaps); /* Don't ask for more than caller has */
end_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
error = XFS_BMAPI(mp, NULL, io, offset_fsb,
(xfs_filblks_t)(end_fsb - offset_fsb),
flags, NULL, 0, imap,
&nimaps, NULL);
if (error) {
return XFS_ERROR(error);
}
if(nimaps) {
*npbmaps = _xfs_imap_to_bmap(io, offset, imap, pbmapp, nimaps,
*npbmaps);
} else
*npbmaps = 0;
return XFS_ERROR(error);
}
/*
* xfs_iomap_write: return pagebuf_bmap_t's telling higher layers
* where to write.
* There are 2 main cases:
* 1 the extents already exist
* 2 must allocate.
* There are 3 cases when we allocate:
* delay allocation (doesn't really allocate or use transactions)
* direct allocation (no previous delay allocation)
* convert delay to real allocations
*/
STATIC int
xfs_iomap_write(
xfs_iocore_t *io,
loff_t offset,
size_t count,
page_buf_bmap_t *pbmapp,
int *npbmaps,
int ioflag)
{
int maps;
int error = 0;
int found;
int flags = 0;
maps = *npbmaps;
if (!maps)
goto out;
/*
* If we have extents that are allocated for this range,
* return them.
*/
found = 0;
error = xfs_iomap_read(io, offset, count, flags, pbmapp, npbmaps);
if (error)
goto out;
/*
* If we found mappings and they can just have data written
* without conversion,
* let the caller write these and call us again.
*
* If we have a HOLE or UNWRITTEN, proceed down lower to
* get the space or to convert to written.
*/
if (*npbmaps) {
if (!(pbmapp->pbm_flags & PBMF_HOLE)) {
*npbmaps = 1; /* Only checked the first one. */
/* We could check more, ... */
goto out;
}
}
found = *npbmaps;
*npbmaps = maps; /* Restore to original requested */
if (ioflag & PBF_DIRECT) {
error = xfs_iomap_write_direct(io, offset, count, pbmapp,
npbmaps, ioflag, found);
} else {
error = xfs_iomap_write_delay(io, offset, count, pbmapp,
npbmaps, ioflag, found);
}
out:
XFS_IUNLOCK(io->io_mount, io, XFS_ILOCK_EXCL);
return XFS_ERROR(error);
}
STATIC int
xfs_iomap_write_delay(
xfs_iocore_t *io,
loff_t offset,
size_t count,
page_buf_bmap_t *pbmapp,
int *npbmaps,
int ioflag,
int found)
{
xfs_fileoff_t offset_fsb;
xfs_fileoff_t ioalign;
xfs_fileoff_t last_fsb;
xfs_fileoff_t start_fsb;
xfs_filblks_t count_fsb;
xfs_off_t aligned_offset;
xfs_fsize_t isize;
xfs_fsblock_t firstblock;
int nimaps;
int error;
int n;
unsigned int iosize;
xfs_mount_t *mp;
#define XFS_WRITE_IMAPS XFS_BMAP_MAX_NMAP
xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS];
int aeof;
ASSERT(ismrlocked(io->io_lock, MR_UPDATE) != 0);
mp = io->io_mount;
isize = XFS_SIZE(mp, io);
if (io->io_new_size > isize) {
isize = io->io_new_size;
}
aeof = 0;
offset_fsb = XFS_B_TO_FSBT(mp, offset);
last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
/*
* If the caller is doing a write at the end of the file,
* then extend the allocation (and the buffer used for the write)
* out to the file system's write iosize. We clean up any extra
* space left over when the file is closed in xfs_inactive().
* We can only do this if we are sure that we will create buffers
* over all of the space we allocate beyond the end of the file.
* Not doing so would allow us to create delalloc blocks with
* no pages in memory covering them. So, we need to check that
* there are not any real blocks in the area beyond the end of
* the file which we are optimistically going to preallocate. If
* there are then our buffers will stop when they encounter them
* and we may accidentally create delalloc blocks beyond them
* that we never cover with a buffer. All of this is because
* we are not actually going to write the extra blocks preallocated
* at this point.
*
* We don't bother with this for sync writes, because we need
* to minimize the amount we write for good performance.
*/
if (!(ioflag & PBF_SYNC) && ((offset + count) > XFS_SIZE(mp, io))) {
start_fsb = XFS_B_TO_FSBT(mp,
((xfs_ufsize_t)(offset + count - 1)));
count_fsb = mp->m_writeio_blocks;
while (count_fsb > 0) {
nimaps = XFS_WRITE_IMAPS;
error = XFS_BMAPI(mp, NULL, io, start_fsb, count_fsb,
0, NULL, 0, imap, &nimaps,
NULL);
if (error) {
return error;
}
for (n = 0; n < nimaps; n++) {
if ((imap[n].br_startblock != HOLESTARTBLOCK) &&
(imap[n].br_startblock != DELAYSTARTBLOCK)) {
goto write_map;
}
start_fsb += imap[n].br_blockcount;
count_fsb -= imap[n].br_blockcount;
ASSERT(count_fsb < 0xffff000);
}
}
iosize = mp->m_writeio_blocks;
aligned_offset = XFS_WRITEIO_ALIGN(mp, (offset + count - 1));
ioalign = XFS_B_TO_FSBT(mp, aligned_offset);
last_fsb = ioalign + iosize;
aeof = 1;
}
write_map:
nimaps = XFS_WRITE_IMAPS;
firstblock = NULLFSBLOCK;
/*
* roundup the allocation request to m_dalign boundary if file size
* is greater that 512K and we are allocating past the allocation eof
*/
if (mp->m_dalign && (XFS_SIZE(mp, io) >= mp->m_dalign) && aeof) {
int eof;
xfs_fileoff_t new_last_fsb;
new_last_fsb = roundup_64(last_fsb, mp->m_dalign);
error = XFS_BMAP_EOF(mp, io, new_last_fsb, XFS_DATA_FORK, &eof);
if (error) {
return error;
}
if (eof) {
last_fsb = new_last_fsb;
}
}
error = XFS_BMAPI(mp, NULL, io, offset_fsb,
(xfs_filblks_t)(last_fsb - offset_fsb),
XFS_BMAPI_DELAY | XFS_BMAPI_WRITE |
XFS_BMAPI_ENTIRE, &firstblock, 1, imap,
&nimaps, NULL);
/*
* This can be EDQUOT, if nimaps == 0
*/
if (error) {
return XFS_ERROR(error);
}
/*
* If bmapi returned us nothing, and if we didn't get back EDQUOT,
* then we must have run out of space.
*/
if (nimaps == 0) {
return XFS_ERROR(ENOSPC);
}
/*
* Now map our desired I/O size and alignment over the
* extents returned by xfs_bmapi().
*/
*npbmaps = _xfs_imap_to_bmap(io, offset, imap, pbmapp,
nimaps, *npbmaps);
return 0;
}
STATIC int
xfs_iomap_write_direct(
xfs_iocore_t *io,
loff_t offset,
size_t count,
page_buf_bmap_t *pbmapp,
int *npbmaps,
int ioflag,
int found)
{
xfs_inode_t *ip = XFS_IO_INODE(io);
xfs_mount_t *mp;
xfs_fileoff_t offset_fsb;
xfs_fileoff_t last_fsb;
xfs_filblks_t count_fsb;
xfs_fsize_t isize;
xfs_fsblock_t firstfsb;
int nimaps, maps;
int error;
xfs_trans_t *tp;
#define XFS_WRITE_IMAPS XFS_BMAP_MAX_NMAP
xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS], *imapp;
xfs_bmap_free_t free_list;
int aeof;
int bmapi_flags;
xfs_filblks_t datablocks;
int rt;
int committed;
int numrtextents;
uint resblks;
int rtextsize;
maps = min(XFS_WRITE_IMAPS, *npbmaps);
nimaps = maps;
mp = io->io_mount;
isize = XFS_SIZE(mp, io);
if (io->io_new_size > isize)
isize = io->io_new_size;
aeof = ((offset + count) > isize) ? 1 : 0;
offset_fsb = XFS_B_TO_FSBT(mp, offset);
last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
count_fsb = last_fsb - offset_fsb;
if (found && (pbmapp->pbm_flags & PBMF_HOLE)) {
xfs_fileoff_t map_last_fsb;
map_last_fsb = XFS_B_TO_FSB(mp,
(pbmapp->pbm_bsize + pbmapp->pbm_offset));
if (map_last_fsb < last_fsb) {
last_fsb = map_last_fsb;
count_fsb = last_fsb - offset_fsb;
}
ASSERT(count_fsb > 0);
}
/*
* roundup the allocation request to m_dalign boundary if file size
* is greater that 512K and we are allocating past the allocation eof
*/
if (!found && mp->m_dalign && (isize >= 524288) && aeof) {
int eof;
xfs_fileoff_t new_last_fsb;
new_last_fsb = roundup_64(last_fsb, mp->m_dalign);
printk("xfs_iomap_write_direct: about to XFS_BMAP_EOF %Ld\n",
new_last_fsb);
error = XFS_BMAP_EOF(mp, io, new_last_fsb, XFS_DATA_FORK, &eof);
if (error)
goto error_out;
if (eof)
last_fsb = new_last_fsb;
}
bmapi_flags = XFS_BMAPI_WRITE|XFS_BMAPI_DIRECT_IO|XFS_BMAPI_ENTIRE;
bmapi_flags &= ~XFS_BMAPI_DIRECT_IO;
/*
* determine if this is a realtime file
*/
if ((rt = (ip->i_d.di_flags & XFS_DIFLAG_REALTIME)) != 0) {
rtextsize = mp->m_sb.sb_rextsize;
} else
rtextsize = 0;
error = 0;
/*
* allocate file space for the bmapp entries passed in.
*/
/*
* determine if reserving space on
* the data or realtime partition.
*/
if (rt) {
numrtextents = (count_fsb + rtextsize - 1);
do_div(numrtextents, rtextsize);
datablocks = 0;
} else {
datablocks = count_fsb;
numrtextents = 0;
}
/*
* allocate and setup the transaction
*/
tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
resblks = XFS_DIOSTRAT_SPACE_RES(mp, datablocks);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
error = xfs_trans_reserve(tp,
resblks,
XFS_WRITE_LOG_RES(mp),
numrtextents,
XFS_TRANS_PERM_LOG_RES,
XFS_WRITE_LOG_COUNT);
/*
* check for running out of space
*/
if (error) {
/*
* Free the transaction structure.
*/
xfs_trans_cancel(tp, 0);
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
if (error) {
goto error_out; /* Don't return in above if .. trans ..,
need lock to return */
}
if (XFS_IS_QUOTA_ON(mp)) {
if (xfs_trans_reserve_quota(tp,
ip->i_udquot,
ip->i_gdquot,
resblks, 0, 0)) {
error = (EDQUOT);
goto error1;
}
nimaps = 1;
} else {
nimaps = 2;
}
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
/*
* issue the bmapi() call to allocate the blocks
*/
XFS_BMAP_INIT(&free_list, &firstfsb);
imapp = &imap[0];
error = XFS_BMAPI(mp, tp, io, offset_fsb, count_fsb,
bmapi_flags, &firstfsb, 1, imapp, &nimaps, &free_list);
if (error) {
goto error0;
}
/*
* complete the transaction
*/
error = xfs_bmap_finish(&tp, &free_list, firstfsb, &committed);
if (error) {
goto error0;
}
error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
if (error) {
goto error_out;
}
/* copy any maps to caller's array and return any error. */
if (nimaps == 0) {
error = (ENOSPC);
goto error_out;
}
maps = min(nimaps, maps);
*npbmaps = _xfs_imap_to_bmap(io, offset, &imap[0], pbmapp, maps,
*npbmaps);
if (*npbmaps) {
/*
* this is new since xfs_iomap_read
* didn't find it.
*/
if (*npbmaps != 1) {
/* NEED MORE WORK FOR MULTIPLE BMAPS (which are new) */
BUG();
}
}
goto out;
error0: /* Cancel bmap, unlock inode, and cancel trans */
xfs_bmap_cancel(&free_list);
error1: /* Just cancel transaction */
xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
*npbmaps = 0; /* nothing set-up here */
error_out:
out: /* Just return error and any tracing at end of routine */
return XFS_ERROR(error);
}
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