From e023b2e244ddcc25308309d20c6bfd037897b10c Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 8 May 2012 16:51:41 +0200 Subject: block: fix snapshot on QED QED's opaque data includes a pointer back to the BlockDriverState. This breaks when bdrv_append shuffles data between bs_new and bs_top. To avoid this, add a "rebind" function that tells the driver about the new relationship between the BlockDriverState and its opaque. The patch also adds rebind to VVFAT for completeness, even though it is not used with live snapshots. Reviewed-by: Stefan Hajnoczi Reviewed-by: Kevin Wolf Signed-off-by: Paolo Bonzini Signed-off-by: Kevin Wolf --- block.c | 10 ++++++++++ block/qed.c | 7 +++++++ block/vvfat.c | 7 +++++++ block_int.h | 1 + 4 files changed, 25 insertions(+) diff --git a/block.c b/block.c index 3db84cd241..87600a54dd 100644 --- a/block.c +++ b/block.c @@ -949,6 +949,13 @@ void bdrv_make_anon(BlockDriverState *bs) bs->device_name[0] = '\0'; } +static void bdrv_rebind(BlockDriverState *bs) +{ + if (bs->drv && bs->drv->bdrv_rebind) { + bs->drv->bdrv_rebind(bs); + } +} + /* * Add new bs contents at the top of an image chain while the chain is * live, while keeping required fields on the top layer. @@ -1037,6 +1044,9 @@ void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top) bs_new->slice_time = 0; bs_new->slice_start = 0; bs_new->slice_end = 0; + + bdrv_rebind(bs_new); + bdrv_rebind(bs_top); } void bdrv_delete(BlockDriverState *bs) diff --git a/block/qed.c b/block/qed.c index 366cde7ad8..30a31f907f 100644 --- a/block/qed.c +++ b/block/qed.c @@ -367,6 +367,12 @@ static void qed_cancel_need_check_timer(BDRVQEDState *s) qemu_del_timer(s->need_check_timer); } +static void bdrv_qed_rebind(BlockDriverState *bs) +{ + BDRVQEDState *s = bs->opaque; + s->bs = bs; +} + static int bdrv_qed_open(BlockDriverState *bs, int flags) { BDRVQEDState *s = bs->opaque; @@ -1550,6 +1556,7 @@ static BlockDriver bdrv_qed = { .create_options = qed_create_options, .bdrv_probe = bdrv_qed_probe, + .bdrv_rebind = bdrv_qed_rebind, .bdrv_open = bdrv_qed_open, .bdrv_close = bdrv_qed_close, .bdrv_create = bdrv_qed_create, diff --git a/block/vvfat.c b/block/vvfat.c index 9ef21ddfc5..2dc9d50888 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -982,6 +982,12 @@ static BDRVVVFATState *vvv = NULL; static int enable_write_target(BDRVVVFATState *s); static int is_consistent(BDRVVVFATState *s); +static void vvfat_rebind(BlockDriverState *bs) +{ + BDRVVVFATState *s = bs->opaque; + s->bs = bs; +} + static int vvfat_open(BlockDriverState *bs, const char* dirname, int flags) { BDRVVVFATState *s = bs->opaque; @@ -2855,6 +2861,7 @@ static BlockDriver bdrv_vvfat = { .format_name = "vvfat", .instance_size = sizeof(BDRVVVFATState), .bdrv_file_open = vvfat_open, + .bdrv_rebind = vvfat_rebind, .bdrv_read = vvfat_co_read, .bdrv_write = vvfat_co_write, .bdrv_close = vvfat_close, diff --git a/block_int.h b/block_int.h index 086832aab9..fbbc7aeb1a 100644 --- a/block_int.h +++ b/block_int.h @@ -140,6 +140,7 @@ struct BlockDriver { int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num, const uint8_t *buf, int nb_sectors); void (*bdrv_close)(BlockDriverState *bs); + void (*bdrv_rebind)(BlockDriverState *bs); int (*bdrv_create)(const char *filename, QEMUOptionParameter *options); int (*bdrv_set_key)(BlockDriverState *bs, const char *key); int (*bdrv_make_empty)(BlockDriverState *bs); -- cgit v1.2.1