int
xfs_iomap(
xfs_inode_t *ip,
xfs_off_t offset,
ssize_t count,
int flags,
xfs_iomap_t *iomapp,
int *niomaps)
{
xfs_mount_t *mp = ip->i_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;
ASSERT((ip->i_d.di_mode & S_IFMT) == S_IFREG);
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
switch (flags & (BMAPI_READ | BMAPI_WRITE | BMAPI_ALLOCATE)) {
case BMAPI_READ:
xfs_iomap_enter_trace(XFS_IOMAP_READ_ENTER, ip, offset, count);
lockmode = xfs_ilock_map_shared(ip);
bmapi_flags = XFS_BMAPI_ENTIRE;
break;
case BMAPI_WRITE:
xfs_iomap_enter_trace(XFS_IOMAP_WRITE_ENTER, ip, offset, count);
lockmode = XFS_ILOCK_EXCL;
if (flags & BMAPI_IGNSTATE)
bmapi_flags |= XFS_BMAPI_IGSTATE|XFS_BMAPI_ENTIRE;
xfs_ilock(ip, lockmode);
break;
case BMAPI_ALLOCATE:
xfs_iomap_enter_trace(XFS_IOMAP_ALLOC_ENTER, ip, offset, count);
lockmode = XFS_ILOCK_SHARED;
bmapi_flags = XFS_BMAPI_ENTIRE;
/* Attempt non-blocking lock */
if (flags & BMAPI_TRYLOCK) {
if (!xfs_ilock_nowait(ip, lockmode))
return XFS_ERROR(EAGAIN);
} else {
xfs_ilock(ip, lockmode);
}
break;
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(NULL, ip, offset_fsb,
(xfs_filblks_t)(end_fsb - offset_fsb),
bmapi_flags, NULL, 0, &imap,
&nimaps, NULL, NULL);
if (error)
goto out;
switch (flags & (BMAPI_WRITE|BMAPI_ALLOCATE)) {
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, ip,
offset, count, iomapp, &imap, flags);
break;
}
if (flags & (BMAPI_DIRECT|BMAPI_MMAP)) {
error = xfs_iomap_write_direct(ip, offset, count, flags,
&imap, &nimaps, nimaps);
} else {
error = xfs_iomap_write_delay(ip, offset, count, flags,
&imap, &nimaps);
}
if (!error) {
xfs_iomap_map_trace(XFS_IOMAP_ALLOC_MAP, ip,
offset, count, iomapp, &imap, flags);
}
iomap_flags = IOMAP_NEW;
break;
case BMAPI_ALLOCATE:
/* If we found an extent, return it */
xfs_iunlock(ip, lockmode);
lockmode = 0;
if (nimaps && !isnullstartblock(imap.br_startblock)) {
xfs_iomap_map_trace(XFS_IOMAP_WRITE_MAP, ip,
offset, count, iomapp, &imap, flags);
break;
}
error = xfs_iomap_write_allocate(ip, offset, count,
&imap, &nimaps);
break;
}
if (nimaps) {
*niomaps = xfs_imap_to_bmap(ip, offset, &imap,
iomapp, nimaps, *niomaps, iomap_flags);
} else if (niomaps) {
*niomaps = 0;
}
out:
if (lockmode)
xfs_iunlock(ip, lockmode);
return XFS_ERROR(error);
}
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, 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);
}