Commit 0bce597d authored by Jeff Cody's avatar Jeff Cody Committed by Kevin Wolf
Browse files

block: convert bdrv_commit() to use bdrv_reopen() 



Currently, bdrv_commit() reopens images r/w itself, via risky
_delete() and _open() calls. Use the new safe method for drive reopen.

Signed-off-by: default avatarJeff Cody <jcody@redhat.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent 3fe4b700

block.c

+5 −43
Original line number Diff line number Diff line
@@ -1501,13 +1501,11 @@ int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix) 
int bdrv_commit(BlockDriverState *bs)

{

    BlockDriver *drv = bs->drv;

    BlockDriver *backing_drv;

    int64_t sector, total_sectors;

    int n, ro, open_flags;

    int ret = 0, rw_ret = 0;

    int ret = 0;

    uint8_t *buf;

    char filename[1024];

    BlockDriverState *bs_rw, *bs_ro;



    if (!drv)

        return -ENOMEDIUM;
@@ -1516,42 +1514,18 @@ int bdrv_commit(BlockDriverState *bs) 
        return -ENOTSUP;

    }



    if (bs->backing_hd->keep_read_only) {

        return -EACCES;

    }



    if (bdrv_in_use(bs) || bdrv_in_use(bs->backing_hd)) {

        return -EBUSY;

    }



    backing_drv = bs->backing_hd->drv;

    ro = bs->backing_hd->read_only;

    strncpy(filename, bs->backing_hd->filename, sizeof(filename));

    open_flags =  bs->backing_hd->open_flags;



    if (ro) {

        /* re-open as RW */

        bdrv_delete(bs->backing_hd);

        bs->backing_hd = NULL;

        bs_rw = bdrv_new("");

        rw_ret = bdrv_open(bs_rw, filename, open_flags | BDRV_O_RDWR,

            backing_drv);

        if (rw_ret < 0) {

            bdrv_delete(bs_rw);

            /* try to re-open read-only */

            bs_ro = bdrv_new("");

            ret = bdrv_open(bs_ro, filename, open_flags & ~BDRV_O_RDWR,

                backing_drv);

            if (ret < 0) {

                bdrv_delete(bs_ro);

                /* drive not functional anymore */

                bs->drv = NULL;

                return ret;

            }

            bs->backing_hd = bs_ro;

            return rw_ret;

        if (bdrv_reopen(bs->backing_hd, open_flags | BDRV_O_RDWR, NULL)) {

            return -EACCES;

        }

        bs->backing_hd = bs_rw;

    }



    total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
@@ -1588,20 +1562,8 @@ ro_cleanup: 
    g_free(buf);



    if (ro) {

        /* re-open as RO */

        bdrv_delete(bs->backing_hd);

        bs->backing_hd = NULL;

        bs_ro = bdrv_new("");

        ret = bdrv_open(bs_ro, filename, open_flags & ~BDRV_O_RDWR,

            backing_drv);

        if (ret < 0) {

            bdrv_delete(bs_ro);

            /* drive not functional anymore */

            bs->drv = NULL;

            return ret;

        }

        bs->backing_hd = bs_ro;

        bs->backing_hd->keep_read_only = 0;

        /* ignoring error return here */

        bdrv_reopen(bs->backing_hd, open_flags & ~BDRV_O_RDWR, NULL);

    }



    return ret;