Commit c6bb9ad1 authored by Federico Simoncelli's avatar Federico Simoncelli Committed by Kevin Wolf
Browse files

qemu-img: find the image end offset during check 



This patch adds the support for reporting the image end offset (in
bytes). This is particularly useful after a conversion (or a rebase)
where the destination is a block device in order to find the first
unused byte at the end of the image.

Signed-off-by: default avatarFederico Simoncelli <fsimonce@redhat.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent 5cbb0828

block/qcow2-refcount.c

+8 −2
Original line number Diff line number Diff line
@@ -1112,7 +1112,7 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, 
                          BdrvCheckMode fix)

{

    BDRVQcowState *s = bs->opaque;

    int64_t size, i;

    int64_t size, i, highest_cluster;

    int nb_clusters, refcount1, refcount2;

    QCowSnapshot *sn;

    uint16_t *refcount_table;
@@ -1183,7 +1183,7 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, 
    }



    /* compare ref counts */

    for(i = 0; i < nb_clusters; i++) {

    for (i = 0, highest_cluster = 0; i < nb_clusters; i++) {

        refcount1 = get_refcount(bs, i);

        if (refcount1 < 0) {

            fprintf(stderr, "Can't get refcount for cluster %" PRId64 ": %s\n",
@@ -1193,6 +1193,11 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, 
        }



        refcount2 = refcount_table[i];



        if (refcount1 > 0 || refcount2 > 0) {

            highest_cluster = i;

        }



        if (refcount1 != refcount2) {



            /* Check if we're allowed to fix the mismatch */
@@ -1227,6 +1232,7 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, 
        }

    }



    res->image_end_offset = (highest_cluster + 1) * s->cluster_size;

    ret = 0;



fail:

include/block/block.h

+1 −0
Original line number Diff line number Diff line
@@ -213,6 +213,7 @@ typedef struct BdrvCheckResult { 
    int check_errors;

    int corruptions_fixed;

    int leaks_fixed;

    int64_t image_end_offset;

    BlockFragInfo bfi;

} BdrvCheckResult;

qemu-img.c

+4 −0
Original line number Diff line number Diff line
@@ -475,6 +475,10 @@ static int img_check(int argc, char **argv) 
        result.bfi.fragmented_clusters * 100.0 / result.bfi.allocated_clusters);

    }



    if (result.image_end_offset > 0) {

        printf("Image end offset: %" PRId64 "\n", result.image_end_offset);

    }



    bdrv_delete(bs);



    if (ret < 0 || result.check_errors) {

tests/qemu-iotests/026

+3 −3
Original line number Diff line number Diff line
@@ -102,7 +102,7 @@ if [ "$event" == "l2_load" ]; then 
    $QEMU_IO -c "read $vmstate 0 128k " $BLKDBG_TEST_IMG | _filter_qemu_io

fi



$QEMU_IMG check $TEST_IMG 2>&1 | grep -v "refcount=1 reference=0"

_check_test_img 2>&1 | grep -v "refcount=1 reference=0"



done

done
@@ -147,7 +147,7 @@ echo 
echo "Event: $event; errno: $errno; imm: $imm; once: $once; write $vmstate"

$QEMU_IO -c "write $vmstate 0 64M" $BLKDBG_TEST_IMG | _filter_qemu_io



$QEMU_IMG check $TEST_IMG 2>&1 | grep -v "refcount=1 reference=0"

_check_test_img 2>&1 | grep -v "refcount=1 reference=0"



done

done
@@ -186,7 +186,7 @@ echo 
echo "Event: $event; errno: $errno; imm: $imm; once: $once"

$QEMU_IO -c "write -b 0 64k" $BLKDBG_TEST_IMG | _filter_qemu_io



$QEMU_IMG check $TEST_IMG 2>&1 | grep -v "refcount=1 reference=0"

_check_test_img 2>&1 | grep -v "refcount=1 reference=0"



done

done

tests/qemu-iotests/036

+2 −1
Original line number Diff line number Diff line
@@ -59,7 +59,8 @@ _make_test_img 64M 
echo

echo === Repair image ===

echo

$QEMU_IMG check -r all $TEST_IMG

_check_test_img -r all



./qcow2.py $TEST_IMG dump-header



# success, all done