| Message ID | 20200218124242.584644-23-mreitz@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | block: Introduce real BdrvChildRole | expand |
Am 18.02.2020 um 13:42 hat Max Reitz geschrieben: > Make all parents of backing files pass the appropriate BdrvChildRole. > By doing so, we can switch their BdrvChildClass over to the generic > child_of_bds, which will do the right thing when given a correct > BdrvChildRole. > > Signed-off-by: Max Reitz <mreitz@redhat.com> > Reviewed-by: Eric Blake <eblake@redhat.com> > --- > block.c | 26 ++++++++++++++++++++------ > block/backup-top.c | 2 +- > block/vvfat.c | 3 ++- > tests/test-bdrv-drain.c | 13 +++++++------ > 4 files changed, 30 insertions(+), 14 deletions(-) > > diff --git a/block.c b/block.c > index 43df38ca30..31affcb4ee 100644 > --- a/block.c > +++ b/block.c > @@ -2770,6 +2770,20 @@ static bool bdrv_inherits_from_recursive(BlockDriverState *child, > return child != NULL; > } > > +/* > + * Return the BdrvChildRole for @bs's backing child. bs->backing is > + * mostly used for COW backing children (role = COW), but also for > + * filtered children (role = FILTERED | PRIMARY). > + */ > +static BdrvChildRole bdrv_backing_role(BlockDriverState *bs) > +{ > + if (bs->drv && bs->drv->is_filter) { > + return BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY; > + } else { > + return BDRV_CHILD_COW; > + } > +} bdrv_mirror_top and bdrv_commit_top don't set .is_filter, so it will return the wrong role for them. (They also don't set .supports_backing, so grepping for that wouldn't help...) > /* > * Sets the backing file link of a BDS. A new reference is created; callers > * which don't need their own reference any more must call bdrv_unref(). > @@ -2797,8 +2811,8 @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, > goto out; > } > > - bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_backing, > - 0, errp); > + bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_of_bds, > + bdrv_backing_role(bs), errp); > /* If backing_hd was already part of bs's backing chain, and > * inherits_from pointed recursively to bs then let's update it to > * point directly to bs (else it will become NULL). */ > @@ -2895,7 +2909,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, > } > > backing_hd = bdrv_open_inherit(backing_filename, reference, options, 0, bs, > - &child_backing, 0, errp); > + &child_of_bds, BDRV_CHILD_COW, errp); Wouldn't it be more consistent to use bdrv_backing_role() here, too? Kevin
On 06.05.20 18:37, Kevin Wolf wrote: > Am 18.02.2020 um 13:42 hat Max Reitz geschrieben: >> Make all parents of backing files pass the appropriate BdrvChildRole. >> By doing so, we can switch their BdrvChildClass over to the generic >> child_of_bds, which will do the right thing when given a correct >> BdrvChildRole. >> >> Signed-off-by: Max Reitz <mreitz@redhat.com> >> Reviewed-by: Eric Blake <eblake@redhat.com> >> --- >> block.c | 26 ++++++++++++++++++++------ >> block/backup-top.c | 2 +- >> block/vvfat.c | 3 ++- >> tests/test-bdrv-drain.c | 13 +++++++------ >> 4 files changed, 30 insertions(+), 14 deletions(-) >> >> diff --git a/block.c b/block.c >> index 43df38ca30..31affcb4ee 100644 >> --- a/block.c >> +++ b/block.c >> @@ -2770,6 +2770,20 @@ static bool bdrv_inherits_from_recursive(BlockDriverState *child, >> return child != NULL; >> } >> >> +/* >> + * Return the BdrvChildRole for @bs's backing child. bs->backing is >> + * mostly used for COW backing children (role = COW), but also for >> + * filtered children (role = FILTERED | PRIMARY). >> + */ >> +static BdrvChildRole bdrv_backing_role(BlockDriverState *bs) >> +{ >> + if (bs->drv && bs->drv->is_filter) { >> + return BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY; >> + } else { >> + return BDRV_CHILD_COW; >> + } >> +} > > bdrv_mirror_top and bdrv_commit_top don't set .is_filter, so it will > return the wrong role for them. (They also don't set .supports_backing, > so grepping for that wouldn't help...) I’ll pull in “block: Mark commit and mirror as filter drivers” from the main series then. >> /* >> * Sets the backing file link of a BDS. A new reference is created; callers >> * which don't need their own reference any more must call bdrv_unref(). >> @@ -2797,8 +2811,8 @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, >> goto out; >> } >> >> - bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_backing, >> - 0, errp); >> + bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_of_bds, >> + bdrv_backing_role(bs), errp); >> /* If backing_hd was already part of bs's backing chain, and >> * inherits_from pointed recursively to bs then let's update it to >> * point directly to bs (else it will become NULL). */ >> @@ -2895,7 +2909,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, >> } >> >> backing_hd = bdrv_open_inherit(backing_filename, reference, options, 0, bs, >> - &child_backing, 0, errp); >> + &child_of_bds, BDRV_CHILD_COW, errp); > > Wouldn't it be more consistent to use bdrv_backing_role() here, too? It’d be indeed. Max
diff --git a/block.c b/block.c index 43df38ca30..31affcb4ee 100644 --- a/block.c +++ b/block.c @@ -2770,6 +2770,20 @@ static bool bdrv_inherits_from_recursive(BlockDriverState *child, return child != NULL; } +/* + * Return the BdrvChildRole for @bs's backing child. bs->backing is + * mostly used for COW backing children (role = COW), but also for + * filtered children (role = FILTERED | PRIMARY). + */ +static BdrvChildRole bdrv_backing_role(BlockDriverState *bs) +{ + if (bs->drv && bs->drv->is_filter) { + return BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY; + } else { + return BDRV_CHILD_COW; + } +} + /* * Sets the backing file link of a BDS. A new reference is created; callers * which don't need their own reference any more must call bdrv_unref(). @@ -2797,8 +2811,8 @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, goto out; } - bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_backing, - 0, errp); + bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_of_bds, + bdrv_backing_role(bs), errp); /* If backing_hd was already part of bs's backing chain, and * inherits_from pointed recursively to bs then let's update it to * point directly to bs (else it will become NULL). */ @@ -2895,7 +2909,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, } backing_hd = bdrv_open_inherit(backing_filename, reference, options, 0, bs, - &child_backing, 0, errp); + &child_of_bds, BDRV_CHILD_COW, errp); if (!backing_hd) { bs->open_flags |= BDRV_O_NO_BACKING; error_prepend(errp, "Could not open backing file: "); @@ -3731,8 +3745,8 @@ int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp) if (state->replace_backing_bs && state->new_backing_bs) { uint64_t nperm, nshared; bdrv_child_perm(state->bs, state->new_backing_bs, - NULL, &child_backing, 0, bs_queue, - state->perm, state->shared_perm, + NULL, &child_of_bds, bdrv_backing_role(state->bs), + bs_queue, state->perm, state->shared_perm, &nperm, &nshared); ret = bdrv_check_update_perm(state->new_backing_bs, NULL, nperm, nshared, NULL, NULL, errp); @@ -6679,7 +6693,7 @@ void bdrv_refresh_filename(BlockDriverState *bs) drv->bdrv_gather_child_options(bs, opts, backing_overridden); } else { QLIST_FOREACH(child, &bs->children, next) { - if (child->klass == &child_backing && !backing_overridden) { + if (child == bs->backing && !backing_overridden) { /* We can skip the backing BDS if it has not been overridden */ continue; } diff --git a/block/backup-top.c b/block/backup-top.c index 9dd89c2fde..c173e61250 100644 --- a/block/backup-top.c +++ b/block/backup-top.c @@ -142,7 +142,7 @@ static void backup_top_child_perm(BlockDriverState *bs, BdrvChild *c, return; } - if (child_class == &child_file) { + if (!(role & BDRV_CHILD_FILTERED)) { /* * Target child * diff --git a/block/vvfat.c b/block/vvfat.c index a945eeb635..8f4ff5a97e 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -3221,7 +3221,8 @@ static void vvfat_child_perm(BlockDriverState *bs, BdrvChild *c, { BDRVVVFATState *s = bs->opaque; - assert(c == s->qcow || child_class == &child_backing); + assert(c == s->qcow || + (child_class == &child_of_bds && (role & BDRV_CHILD_COW))); if (c == s->qcow) { /* This is a private node, nobody should try to attach to it */ diff --git a/tests/test-bdrv-drain.c b/tests/test-bdrv-drain.c index b3d7960bd0..15393a0140 100644 --- a/tests/test-bdrv-drain.c +++ b/tests/test-bdrv-drain.c @@ -96,7 +96,7 @@ static void bdrv_test_child_perm(BlockDriverState *bs, BdrvChild *c, * bdrv_format_default_perms() accepts only these two, so disguise * detach_by_driver_cb_parent as one of them. */ - if (child_class != &child_file && child_class != &child_backing) { + if (child_class != &child_file && child_class != &child_of_bds) { child_class = &child_file; } @@ -1399,8 +1399,8 @@ static void test_detach_indirect(bool by_parent_cb) bdrv_ref(a); child_b = bdrv_attach_child(parent_b, b, "PB-B", &child_file, 0, &error_abort); - child_a = bdrv_attach_child(parent_b, a, "PB-A", &child_backing, 0, - &error_abort); + child_a = bdrv_attach_child(parent_b, a, "PB-A", &child_of_bds, + BDRV_CHILD_COW, &error_abort); bdrv_ref(a); bdrv_attach_child(parent_a, a, "PA-A", @@ -1793,7 +1793,7 @@ static void test_drop_intermediate_poll(void) int i; int ret; - chain_child_class = child_backing; + chain_child_class = child_of_bds; chain_child_class.update_filename = drop_intermediate_poll_update_filename; for (i = 0; i < 3; i++) { @@ -1816,7 +1816,7 @@ static void test_drop_intermediate_poll(void) /* Takes the reference to chain[i - 1] */ chain[i]->backing = bdrv_attach_child(chain[i], chain[i - 1], "chain", &chain_child_class, - 0, &error_abort); + BDRV_CHILD_COW, &error_abort); } } @@ -2034,7 +2034,8 @@ static void do_test_replace_child_mid_drain(int old_drain_count, bdrv_ref(old_child_bs); parent_bs->backing = bdrv_attach_child(parent_bs, old_child_bs, "child", - &child_backing, 0, &error_abort); + &child_of_bds, BDRV_CHILD_COW, + &error_abort); for (i = 0; i < old_drain_count; i++) { bdrv_drained_begin(old_child_bs);