kernel-ark/fs/xfs/xfs_iomap.c
Nathan Scott c31e887807 [XFS] Fix incorrect use of BMAPI_READ in unwritten extent handling
(luckily just cosmetic).

SGI-PV: 942232
SGI-Modid: xfs-linux-melb:xfs-kern:23718a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-09-05 10:06:55 +10:00

992 lines
26 KiB
C

/*
* Copyright (c) 2000-2004 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/
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_inum.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir.h"
#include "xfs_dir2.h"
#include "xfs_alloc.h"
#include "xfs_dmapi.h"
#include "xfs_quota.h"
#include "xfs_mount.h"
#include "xfs_alloc_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_attr_sf.h"
#include "xfs_dir_sf.h"
#include "xfs_dir2_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_bmap.h"
#include "xfs_bit.h"
#include "xfs_rtalloc.h"
#include "xfs_error.h"
#include "xfs_itable.h"
#include "xfs_rw.h"
#include "xfs_acl.h"
#include "xfs_cap.h"
#include "xfs_mac.h"
#include "xfs_attr.h"
#include "xfs_buf_item.h"
#include "xfs_trans_space.h"
#include "xfs_utils.h"
#include "xfs_iomap.h"
#if defined(XFS_RW_TRACE)
void
xfs_iomap_enter_trace(
int tag,
xfs_iocore_t *io,
xfs_off_t offset,
ssize_t count)
{
xfs_inode_t *ip = XFS_IO_INODE(io);
if (!ip->i_rwtrace)
return;
ktrace_enter(ip->i_rwtrace,
(void *)((unsigned long)tag),
(void *)ip,
(void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
(void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
(void *)((unsigned long)((offset >> 32) & 0xffffffff)),
(void *)((unsigned long)(offset & 0xffffffff)),
(void *)((unsigned long)count),
(void *)((unsigned long)((io->io_new_size >> 32) & 0xffffffff)),
(void *)((unsigned long)(io->io_new_size & 0xffffffff)),
(void *)NULL,
(void *)NULL,
(void *)NULL,
(void *)NULL,
(void *)NULL,
(void *)NULL,
(void *)NULL);
}
void
xfs_iomap_map_trace(
int tag,
xfs_iocore_t *io,
xfs_off_t offset,
ssize_t count,
xfs_iomap_t *iomapp,
xfs_bmbt_irec_t *imapp,
int flags)
{
xfs_inode_t *ip = XFS_IO_INODE(io);
if (!ip->i_rwtrace)
return;
ktrace_enter(ip->i_rwtrace,
(void *)((unsigned long)tag),
(void *)ip,
(void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
(void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
(void *)((unsigned long)((offset >> 32) & 0xffffffff)),
(void *)((unsigned long)(offset & 0xffffffff)),
(void *)((unsigned long)count),
(void *)((unsigned long)flags),
(void *)((unsigned long)((iomapp->iomap_offset >> 32) & 0xffffffff)),
(void *)((unsigned long)(iomapp->iomap_offset & 0xffffffff)),
(void *)((unsigned long)(iomapp->iomap_delta)),
(void *)((unsigned long)(iomapp->iomap_bsize)),
(void *)((unsigned long)(iomapp->iomap_bn)),
(void *)(__psint_t)(imapp->br_startoff),
(void *)((unsigned long)(imapp->br_blockcount)),
(void *)(__psint_t)(imapp->br_startblock));
}
#else
#define xfs_iomap_enter_trace(tag, io, offset, count)
#define xfs_iomap_map_trace(tag, io, offset, count, iomapp, imapp, flags)
#endif
#define XFS_WRITEIO_ALIGN(mp,off) (((off) >> mp->m_writeio_log) \
<< mp->m_writeio_log)
#define XFS_STRAT_WRITE_IMAPS 2
#define XFS_WRITE_IMAPS XFS_BMAP_MAX_NMAP
STATIC int
xfs_imap_to_bmap(
xfs_iocore_t *io,
xfs_off_t offset,
xfs_bmbt_irec_t *imap,
xfs_iomap_t *iomapp,
int imaps, /* Number of imap entries */
int iomaps, /* Number of iomap entries */
int flags)
{
xfs_mount_t *mp;
xfs_fsize_t nisize;
int 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 (pbm = 0; imaps && pbm < iomaps; imaps--, iomapp++, imap++, pbm++) {
iomapp->iomap_offset = XFS_FSB_TO_B(mp, imap->br_startoff);
iomapp->iomap_delta = offset - iomapp->iomap_offset;
iomapp->iomap_bsize = XFS_FSB_TO_B(mp, imap->br_blockcount);
iomapp->iomap_flags = flags;
if (io->io_flags & XFS_IOCORE_RT) {
iomapp->iomap_flags |= IOMAP_REALTIME;
iomapp->iomap_target = mp->m_rtdev_targp;
} else {
iomapp->iomap_target = mp->m_ddev_targp;
}
start_block = imap->br_startblock;
if (start_block == HOLESTARTBLOCK) {
iomapp->iomap_bn = IOMAP_DADDR_NULL;
iomapp->iomap_flags |= IOMAP_HOLE;
} else if (start_block == DELAYSTARTBLOCK) {
iomapp->iomap_bn = IOMAP_DADDR_NULL;
iomapp->iomap_flags |= IOMAP_DELAY;
} else {
iomapp->iomap_bn = XFS_FSB_TO_DB_IO(io, start_block);
if (ISUNWRITTEN(imap))
iomapp->iomap_flags |= IOMAP_UNWRITTEN;
}
if ((iomapp->iomap_offset + iomapp->iomap_bsize) >= nisize) {
iomapp->iomap_flags |= IOMAP_EOF;
}
offset += iomapp->iomap_bsize - iomapp->iomap_delta;
}
return pbm; /* Return the number filled */
}
int
xfs_iomap(
xfs_iocore_t *io,
xfs_off_t offset,
ssize_t count,
int flags,
xfs_iomap_t *iomapp,
int *niomaps)
{
xfs_mount_t *mp = io->io_mount;
xfs_fileoff_t offset_fsb, end_fsb;
int error = 0;
int lockmode = 0;
xfs_bmbt_irec_t imap;
int nimaps = 1;
int bmapi_flags = 0;
int iomap_flags = 0;
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
switch (flags &
(BMAPI_READ | BMAPI_WRITE | BMAPI_ALLOCATE |
BMAPI_UNWRITTEN | BMAPI_DEVICE)) {
case BMAPI_READ:
xfs_iomap_enter_trace(XFS_IOMAP_READ_ENTER, io, offset, count);
lockmode = XFS_LCK_MAP_SHARED(mp, io);
bmapi_flags = XFS_BMAPI_ENTIRE;
break;
case BMAPI_WRITE:
xfs_iomap_enter_trace(XFS_IOMAP_WRITE_ENTER, io, offset, count);
lockmode = XFS_ILOCK_EXCL|XFS_EXTSIZE_WR;
if (flags & BMAPI_IGNSTATE)
bmapi_flags |= XFS_BMAPI_IGSTATE|XFS_BMAPI_ENTIRE;
XFS_ILOCK(mp, io, lockmode);
break;
case BMAPI_ALLOCATE:
xfs_iomap_enter_trace(XFS_IOMAP_ALLOC_ENTER, io, offset, count);
lockmode = XFS_ILOCK_SHARED|XFS_EXTSIZE_RD;
bmapi_flags = XFS_BMAPI_ENTIRE;
/* Attempt non-blocking lock */
if (flags & BMAPI_TRYLOCK) {
if (!XFS_ILOCK_NOWAIT(mp, io, lockmode))
return XFS_ERROR(EAGAIN);
} else {
XFS_ILOCK(mp, io, lockmode);
}
break;
case BMAPI_UNWRITTEN:
goto phase2;
case BMAPI_DEVICE:
lockmode = XFS_LCK_MAP_SHARED(mp, io);
iomapp->iomap_target = io->io_flags & XFS_IOCORE_RT ?
mp->m_rtdev_targp : mp->m_ddev_targp;
error = 0;
*niomaps = 1;
goto out;
default:
BUG();
}
ASSERT(offset <= mp->m_maxioffset);
if ((xfs_fsize_t)offset + count > mp->m_maxioffset)
count = mp->m_maxioffset - offset;
end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
offset_fsb = XFS_B_TO_FSBT(mp, offset);
error = XFS_BMAPI(mp, NULL, io, offset_fsb,
(xfs_filblks_t)(end_fsb - offset_fsb),
bmapi_flags, NULL, 0, &imap,
&nimaps, NULL);
if (error)
goto out;
phase2:
switch (flags & (BMAPI_WRITE|BMAPI_ALLOCATE|BMAPI_UNWRITTEN)) {
case BMAPI_WRITE:
/* If we found an extent, return it */
if (nimaps &&
(imap.br_startblock != HOLESTARTBLOCK) &&
(imap.br_startblock != DELAYSTARTBLOCK)) {
xfs_iomap_map_trace(XFS_IOMAP_WRITE_MAP, io,
offset, count, iomapp, &imap, flags);
break;
}
if (flags & (BMAPI_DIRECT|BMAPI_MMAP)) {
error = XFS_IOMAP_WRITE_DIRECT(mp, io, offset,
count, flags, &imap, &nimaps, nimaps);
} else {
error = XFS_IOMAP_WRITE_DELAY(mp, io, offset, count,
flags, &imap, &nimaps);
}
if (!error) {
xfs_iomap_map_trace(XFS_IOMAP_ALLOC_MAP, io,
offset, count, iomapp, &imap, flags);
}
iomap_flags = IOMAP_NEW;
break;
case BMAPI_ALLOCATE:
/* If we found an extent, return it */
XFS_IUNLOCK(mp, io, lockmode);
lockmode = 0;
if (nimaps && !ISNULLSTARTBLOCK(imap.br_startblock)) {
xfs_iomap_map_trace(XFS_IOMAP_WRITE_MAP, io,
offset, count, iomapp, &imap, flags);
break;
}
error = XFS_IOMAP_WRITE_ALLOCATE(mp, io, offset, count,
&imap, &nimaps);
break;
case BMAPI_UNWRITTEN:
lockmode = 0;
error = XFS_IOMAP_WRITE_UNWRITTEN(mp, io, offset, count);
nimaps = 0;
break;
}
if (nimaps) {
*niomaps = xfs_imap_to_bmap(io, offset, &imap,
iomapp, nimaps, *niomaps, iomap_flags);
} else if (niomaps) {
*niomaps = 0;
}
out:
if (lockmode)
XFS_IUNLOCK(mp, io, lockmode);
return XFS_ERROR(error);
}
STATIC int
xfs_flush_space(
xfs_inode_t *ip,
int *fsynced,
int *ioflags)
{
switch (*fsynced) {
case 0:
if (ip->i_delayed_blks) {
xfs_iunlock(ip, XFS_ILOCK_EXCL);
xfs_flush_inode(ip);
xfs_ilock(ip, XFS_ILOCK_EXCL);
*fsynced = 1;
} else {
*ioflags |= BMAPI_SYNC;
*fsynced = 2;
}
return 0;
case 1:
*fsynced = 2;
*ioflags |= BMAPI_SYNC;
return 0;
case 2:
xfs_iunlock(ip, XFS_ILOCK_EXCL);
xfs_flush_device(ip);
xfs_ilock(ip, XFS_ILOCK_EXCL);
*fsynced = 3;
return 0;
}
return 1;
}
int
xfs_iomap_write_direct(
xfs_inode_t *ip,
xfs_off_t offset,
size_t count,
int flags,
xfs_bmbt_irec_t *ret_imap,
int *nmaps,
int found)
{
xfs_mount_t *mp = ip->i_mount;
xfs_iocore_t *io = &ip->i_iocore;
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;
int bmapi_flag;
int quota_flag;
int rt;
xfs_trans_t *tp;
xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS], *imapp;
xfs_bmap_free_t free_list;
int aeof;
xfs_filblks_t qblocks, resblks;
int committed;
int resrtextents;
/*
* Make sure that the dquots are there. This doesn't hold
* the ilock across a disk read.
*/
error = XFS_QM_DQATTACH(ip->i_mount, ip, XFS_QMOPT_ILOCKED);
if (error)
return XFS_ERROR(error);
maps = min(XFS_WRITE_IMAPS, *nmaps);
nimaps = maps;
isize = ip->i_d.di_size;
aeof = (offset + count) > isize;
if (io->io_new_size > isize)
isize = io->io_new_size;
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 && (ret_imap->br_startblock == HOLESTARTBLOCK)) {
xfs_fileoff_t map_last_fsb;
map_last_fsb = ret_imap->br_blockcount + ret_imap->br_startoff;
if (map_last_fsb < last_fsb) {
last_fsb = map_last_fsb;
count_fsb = last_fsb - offset_fsb;
}
ASSERT(count_fsb > 0);
}
/*
* Determine if reserving space on the data or realtime partition.
*/
if ((rt = XFS_IS_REALTIME_INODE(ip))) {
xfs_extlen_t extsz;
if (!(extsz = ip->i_d.di_extsize))
extsz = mp->m_sb.sb_rextsize;
resrtextents = qblocks = (count_fsb + extsz - 1);
do_div(resrtextents, mp->m_sb.sb_rextsize);
resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
quota_flag = XFS_QMOPT_RES_RTBLKS;
} else {
resrtextents = 0;
resblks = qblocks = XFS_DIOSTRAT_SPACE_RES(mp, count_fsb);
quota_flag = XFS_QMOPT_RES_REGBLKS;
}
/*
* Allocate and setup the transaction
*/
xfs_iunlock(ip, XFS_ILOCK_EXCL);
tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
error = xfs_trans_reserve(tp, resblks,
XFS_WRITE_LOG_RES(mp), resrtextents,
XFS_TRANS_PERM_LOG_RES,
XFS_WRITE_LOG_COUNT);
/*
* Check for running out of space, note: need lock to return
*/
if (error)
xfs_trans_cancel(tp, 0);
xfs_ilock(ip, XFS_ILOCK_EXCL);
if (error)
goto error_out;
if (XFS_TRANS_RESERVE_QUOTA_NBLKS(mp, tp, ip, qblocks, 0, quota_flag)) {
error = (EDQUOT);
goto error1;
}
bmapi_flag = XFS_BMAPI_WRITE;
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
if (!(flags & BMAPI_MMAP) && (offset < ip->i_d.di_size || rt))
bmapi_flag |= XFS_BMAPI_PREALLOC;
/*
* Issue the bmapi() call to allocate the blocks
*/
XFS_BMAP_INIT(&free_list, &firstfsb);
nimaps = 1;
imapp = &imap[0];
error = xfs_bmapi(tp, ip, offset_fsb, count_fsb,
bmapi_flag, &firstfsb, 0, 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;
}
*ret_imap = imap[0];
*nmaps = 1;
if ( !(io->io_flags & XFS_IOCORE_RT) && !ret_imap->br_startblock) {
cmn_err(CE_PANIC,"Access to block zero: fs <%s> inode: %lld "
"start_block : %llx start_off : %llx blkcnt : %llx "
"extent-state : %x \n",
(ip->i_mount)->m_fsname,
(long long)ip->i_ino,
ret_imap->br_startblock, ret_imap->br_startoff,
ret_imap->br_blockcount,ret_imap->br_state);
}
return 0;
error0: /* Cancel bmap, unlock inode, unreserve quota blocks, cancel trans */
xfs_bmap_cancel(&free_list);
XFS_TRANS_UNRESERVE_QUOTA_NBLKS(mp, tp, ip, qblocks, 0, quota_flag);
error1: /* Just cancel transaction */
xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
*nmaps = 0; /* nothing set-up here */
error_out:
return XFS_ERROR(error);
}
int
xfs_iomap_write_delay(
xfs_inode_t *ip,
xfs_off_t offset,
size_t count,
int ioflag,
xfs_bmbt_irec_t *ret_imap,
int *nmaps)
{
xfs_mount_t *mp = ip->i_mount;
xfs_iocore_t *io = &ip->i_iocore;
xfs_fileoff_t offset_fsb;
xfs_fileoff_t last_fsb;
xfs_fsize_t isize;
xfs_fsblock_t firstblock;
int nimaps;
int error;
xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS];
int aeof;
int fsynced = 0;
ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE) != 0);
/*
* Make sure that the dquots are there. This doesn't hold
* the ilock across a disk read.
*/
error = XFS_QM_DQATTACH(mp, ip, XFS_QMOPT_ILOCKED);
if (error)
return XFS_ERROR(error);
retry:
isize = ip->i_d.di_size;
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().
*
* For sync writes, we are flushing delayed allocate space to
* try to make additional space available for allocation near
* the filesystem full boundary - preallocation hurts in that
* situation, of course.
*/
if (!(ioflag & BMAPI_SYNC) && ((offset + count) > ip->i_d.di_size)) {
xfs_off_t aligned_offset;
xfs_filblks_t count_fsb;
unsigned int iosize;
xfs_fileoff_t ioalign;
int n;
xfs_fileoff_t start_fsb;
/*
* If there are any real blocks past eof, then don't
* do any speculative allocation.
*/
start_fsb = XFS_B_TO_FSBT(mp,
((xfs_ufsize_t)(offset + count - 1)));
count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_MAXIOFFSET(mp));
while (count_fsb > 0) {
nimaps = XFS_WRITE_IMAPS;
error = XFS_BMAPI(mp, NULL, io, start_fsb, count_fsb,
0, &firstblock, 0, imap, &nimaps, NULL);
if (error) {
return error;
}
for (n = 0; n < nimaps; n++) {
if ( !(io->io_flags & XFS_IOCORE_RT) &&
!imap[n].br_startblock) {
cmn_err(CE_PANIC,"Access to block "
"zero: fs <%s> inode: %lld "
"start_block : %llx start_off "
": %llx blkcnt : %llx "
"extent-state : %x \n",
(ip->i_mount)->m_fsname,
(long long)ip->i_ino,
imap[n].br_startblock,
imap[n].br_startoff,
imap[n].br_blockcount,
imap[n].br_state);
}
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;
}
}
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;
/*
* If mounted with the "-o swalloc" option, roundup the allocation
* request to a stripe width boundary if the file size is >=
* stripe width and we are allocating past the allocation eof.
*/
if (!(io->io_flags & XFS_IOCORE_RT) && mp->m_swidth
&& (mp->m_flags & XFS_MOUNT_SWALLOC)
&& (isize >= XFS_FSB_TO_B(mp, mp->m_swidth)) && aeof) {
int eof;
xfs_fileoff_t new_last_fsb;
new_last_fsb = roundup_64(last_fsb, mp->m_swidth);
error = xfs_bmap_eof(ip, new_last_fsb, XFS_DATA_FORK, &eof);
if (error) {
return error;
}
if (eof) {
last_fsb = new_last_fsb;
}
/*
* Roundup the allocation request to a stripe unit (m_dalign) boundary
* if the file size is >= stripe unit size, and we are allocating past
* the allocation eof.
*/
} else if (!(io->io_flags & XFS_IOCORE_RT) && mp->m_dalign &&
(isize >= XFS_FSB_TO_B(mp, 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(ip, new_last_fsb, XFS_DATA_FORK, &eof);
if (error) {
return error;
}
if (eof) {
last_fsb = new_last_fsb;
}
/*
* Round up the allocation request to a real-time extent boundary
* if the file is on the real-time subvolume.
*/
} else if (io->io_flags & XFS_IOCORE_RT && aeof) {
int eof;
xfs_fileoff_t new_last_fsb;
new_last_fsb = roundup_64(last_fsb, mp->m_sb.sb_rextsize);
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(NULL, ip, 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 && (error != ENOSPC)) {
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) {
xfs_iomap_enter_trace(XFS_IOMAP_WRITE_NOSPACE,
io, offset, count);
if (xfs_flush_space(ip, &fsynced, &ioflag))
return XFS_ERROR(ENOSPC);
error = 0;
goto retry;
}
*ret_imap = imap[0];
*nmaps = 1;
if ( !(io->io_flags & XFS_IOCORE_RT) && !ret_imap->br_startblock) {
cmn_err(CE_PANIC,"Access to block zero: fs <%s> inode: %lld "
"start_block : %llx start_off : %llx blkcnt : %llx "
"extent-state : %x \n",
(ip->i_mount)->m_fsname,
(long long)ip->i_ino,
ret_imap->br_startblock, ret_imap->br_startoff,
ret_imap->br_blockcount,ret_imap->br_state);
}
return 0;
}
/*
* Pass in a delayed allocate extent, convert it to real extents;
* return to the caller the extent we create which maps on top of
* the originating callers request.
*
* Called without a lock on the inode.
*/
int
xfs_iomap_write_allocate(
xfs_inode_t *ip,
xfs_off_t offset,
size_t count,
xfs_bmbt_irec_t *map,
int *retmap)
{
xfs_mount_t *mp = ip->i_mount;
xfs_iocore_t *io = &ip->i_iocore;
xfs_fileoff_t offset_fsb, last_block;
xfs_fileoff_t end_fsb, map_start_fsb;
xfs_fsblock_t first_block;
xfs_bmap_free_t free_list;
xfs_filblks_t count_fsb;
xfs_bmbt_irec_t imap[XFS_STRAT_WRITE_IMAPS];
xfs_trans_t *tp;
int i, nimaps, committed;
int error = 0;
int nres;
*retmap = 0;
/*
* Make sure that the dquots are there.
*/
if ((error = XFS_QM_DQATTACH(mp, ip, 0)))
return XFS_ERROR(error);
offset_fsb = XFS_B_TO_FSBT(mp, offset);
count_fsb = map->br_blockcount;
map_start_fsb = map->br_startoff;
XFS_STATS_ADD(xs_xstrat_bytes, XFS_FSB_TO_B(mp, count_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;
while (nimaps == 0) {
tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
nres = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK);
error = xfs_trans_reserve(tp, nres,
XFS_WRITE_LOG_RES(mp),
0, XFS_TRANS_PERM_LOG_RES,
XFS_WRITE_LOG_COUNT);
if (error == ENOSPC) {
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);
return XFS_ERROR(error);
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
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, ip->i_d.di_size);
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) {
error = EAGAIN;
goto trans_cancel;
}
}
/* Go get the actual blocks */
error = xfs_bmapi(tp, ip, map_start_fsb, count_fsb,
XFS_BMAPI_WRITE, &first_block, 1,
imap, &nimaps, &free_list);
if (error)
goto trans_cancel;
error = xfs_bmap_finish(&tp, &free_list,
first_block, &committed);
if (error)
goto trans_cancel;
error = xfs_trans_commit(tp,
XFS_TRANS_RELEASE_LOG_RES, NULL);
if (error)
goto error0;
xfs_iunlock(ip, XFS_ILOCK_EXCL);
}
/*
* See if we were able to allocate an extent that
* covers at least part of the callers request
*/
for (i = 0; i < nimaps; i++) {
if ( !(io->io_flags & XFS_IOCORE_RT) &&
!imap[i].br_startblock) {
cmn_err(CE_PANIC,"Access to block zero: "
"fs <%s> inode: %lld "
"start_block : %llx start_off : %llx "
"blkcnt : %llx extent-state : %x \n",
(ip->i_mount)->m_fsname,
(long long)ip->i_ino,
imap[i].br_startblock,
imap[i].br_startoff,
imap[i].br_blockcount,imap[i].br_state);
}
if ((offset_fsb >= imap[i].br_startoff) &&
(offset_fsb < (imap[i].br_startoff +
imap[i].br_blockcount))) {
*map = imap[i];
*retmap = 1;
XFS_STATS_INC(xs_xstrat_quick);
return 0;
}
count_fsb -= imap[i].br_blockcount;
}
/* So far we have not mapped the requested part of the
* file, just surrounding data, try again.
*/
nimaps--;
map_start_fsb = imap[nimaps].br_startoff +
imap[nimaps].br_blockcount;
}
trans_cancel:
xfs_bmap_cancel(&free_list);
xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
error0:
xfs_iunlock(ip, XFS_ILOCK_EXCL);
return XFS_ERROR(error);
}
int
xfs_iomap_write_unwritten(
xfs_inode_t *ip,
xfs_off_t offset,
size_t count)
{
xfs_mount_t *mp = ip->i_mount;
xfs_iocore_t *io = &ip->i_iocore;
xfs_trans_t *tp;
xfs_fileoff_t offset_fsb;
xfs_filblks_t count_fsb;
xfs_filblks_t numblks_fsb;
xfs_bmbt_irec_t imap;
int committed;
int error;
int nres;
int nimaps;
xfs_fsblock_t firstfsb;
xfs_bmap_free_t free_list;
xfs_iomap_enter_trace(XFS_IOMAP_UNWRITTEN,
&ip->i_iocore, offset, count);
offset_fsb = XFS_B_TO_FSBT(mp, offset);
count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
count_fsb = (xfs_filblks_t)(count_fsb - offset_fsb);
do {
nres = XFS_DIOSTRAT_SPACE_RES(mp, 0);
/*
* set up a transaction to convert the range of extents
* from unwritten to real. Do allocations in a loop until
* we have covered the range passed in.
*/
tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
error = xfs_trans_reserve(tp, nres,
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);
/*
* Modify the unwritten extent state of the buffer.
*/
XFS_BMAP_INIT(&free_list, &firstfsb);
nimaps = 1;
error = xfs_bmapi(tp, ip, offset_fsb, count_fsb,
XFS_BMAPI_WRITE, &firstfsb,
1, &imap, &nimaps, &free_list);
if (error)
goto error_on_bmapi_transaction;
error = xfs_bmap_finish(&(tp), &(free_list),
firstfsb, &committed);
if (error)
goto error_on_bmapi_transaction;
error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
if (error)
goto error0;
if ( !(io->io_flags & XFS_IOCORE_RT) && !imap.br_startblock) {
cmn_err(CE_PANIC,"Access to block zero: fs <%s> "
"inode: %lld start_block : %llx start_off : "
"%llx blkcnt : %llx extent-state : %x \n",
(ip->i_mount)->m_fsname,
(long long)ip->i_ino,
imap.br_startblock,imap.br_startoff,
imap.br_blockcount,imap.br_state);
}
if ((numblks_fsb = imap.br_blockcount) == 0) {
/*
* The numblks_fsb value should always get
* smaller, otherwise the loop is stuck.
*/
ASSERT(imap.br_blockcount);
break;
}
offset_fsb += numblks_fsb;
count_fsb -= numblks_fsb;
} while (count_fsb > 0);
return 0;
error_on_bmapi_transaction:
xfs_bmap_cancel(&free_list);
xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT));
xfs_iunlock(ip, XFS_ILOCK_EXCL);
error0:
return XFS_ERROR(error);
}