raw-posix: add discard support

Add support to discard blocks in a raw image residing on an XFS filesystem
by calling the XFS_IOC_UNRESVSP64 ioctl to punch holes.  Support for other
hole punching mechanisms can be added when they become available.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Christoph Hellwig 2010-12-17 11:41:15 +01:00 committed by Kevin Wolf
parent edff5db1f5
commit dce512dedf
2 changed files with 71 additions and 0 deletions

View File

@ -69,6 +69,10 @@
#include <sys/diskslice.h> #include <sys/diskslice.h>
#endif #endif
#ifdef CONFIG_XFS
#include <xfs/xfs.h>
#endif
//#define DEBUG_FLOPPY //#define DEBUG_FLOPPY
//#define DEBUG_BLOCK //#define DEBUG_BLOCK
@ -120,6 +124,9 @@ typedef struct BDRVRawState {
#endif #endif
uint8_t *aligned_buf; uint8_t *aligned_buf;
unsigned aligned_buf_size; unsigned aligned_buf_size;
#ifdef CONFIG_XFS
bool is_xfs : 1;
#endif
} BDRVRawState; } BDRVRawState;
static int fd_open(BlockDriverState *bs); static int fd_open(BlockDriverState *bs);
@ -196,6 +203,12 @@ static int raw_open_common(BlockDriverState *bs, const char *filename,
#endif #endif
} }
#ifdef CONFIG_XFS
if (platform_test_xfs_fd(s->fd)) {
s->is_xfs = 1;
}
#endif
return 0; return 0;
out_free_buf: out_free_buf:
@ -740,6 +753,37 @@ static int raw_flush(BlockDriverState *bs)
return qemu_fdatasync(s->fd); return qemu_fdatasync(s->fd);
} }
#ifdef CONFIG_XFS
static int xfs_discard(BDRVRawState *s, int64_t sector_num, int nb_sectors)
{
struct xfs_flock64 fl;
memset(&fl, 0, sizeof(fl));
fl.l_whence = SEEK_SET;
fl.l_start = sector_num << 9;
fl.l_len = (int64_t)nb_sectors << 9;
if (xfsctl(NULL, s->fd, XFS_IOC_UNRESVSP64, &fl) < 0) {
DEBUG_BLOCK_PRINT("cannot punch hole (%s)\n", strerror(errno));
return -errno;
}
return 0;
}
#endif
static int raw_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors)
{
#ifdef CONFIG_XFS
BDRVRawState *s = bs->opaque;
if (s->is_xfs) {
return xfs_discard(s, sector_num, nb_sectors);
}
#endif
return 0;
}
static QEMUOptionParameter raw_create_options[] = { static QEMUOptionParameter raw_create_options[] = {
{ {
@ -761,6 +805,7 @@ static BlockDriver bdrv_file = {
.bdrv_close = raw_close, .bdrv_close = raw_close,
.bdrv_create = raw_create, .bdrv_create = raw_create,
.bdrv_flush = raw_flush, .bdrv_flush = raw_flush,
.bdrv_discard = raw_discard,
.bdrv_aio_readv = raw_aio_readv, .bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev, .bdrv_aio_writev = raw_aio_writev,

26
configure vendored
View File

@ -288,6 +288,7 @@ xen=""
linux_aio="" linux_aio=""
attr="" attr=""
vhost_net="" vhost_net=""
xfs=""
gprof="no" gprof="no"
debug_tcg="no" debug_tcg="no"
@ -1398,6 +1399,27 @@ EOF
fi fi
fi fi
##########################################
# xfsctl() probe, used for raw-posix
if test "$xfs" != "no" ; then
cat > $TMPC << EOF
#include <xfs/xfs.h>
int main(void)
{
xfsctl(NULL, 0, 0, NULL);
return 0;
}
EOF
if compile_prog "" "" ; then
xfs="yes"
else
if test "$xfs" = "yes" ; then
feature_not_found "xfs"
fi
xfs=no
fi
fi
########################################## ##########################################
# vde libraries probe # vde libraries probe
if test "$vde" != "no" ; then if test "$vde" != "no" ; then
@ -2403,6 +2425,7 @@ echo "Trace backend $trace_backend"
echo "Trace output file $trace_file-<pid>" echo "Trace output file $trace_file-<pid>"
echo "spice support $spice" echo "spice support $spice"
echo "rbd support $rbd" echo "rbd support $rbd"
echo "xfsctl support $xfs"
if test $sdl_too_old = "yes"; then if test $sdl_too_old = "yes"; then
echo "-> Your SDL version is too old - please upgrade to have SDL support" echo "-> Your SDL version is too old - please upgrade to have SDL support"
@ -2548,6 +2571,9 @@ fi
if test "$uuid" = "yes" ; then if test "$uuid" = "yes" ; then
echo "CONFIG_UUID=y" >> $config_host_mak echo "CONFIG_UUID=y" >> $config_host_mak
fi fi
if test "$xfs" = "yes" ; then
echo "CONFIG_XFS=y" >> $config_host_mak
fi
qemu_version=`head $source_path/VERSION` qemu_version=`head $source_path/VERSION`
echo "VERSION=$qemu_version" >>$config_host_mak echo "VERSION=$qemu_version" >>$config_host_mak
echo "PKGVERSION=$pkgversion" >>$config_host_mak echo "PKGVERSION=$pkgversion" >>$config_host_mak