| Message ID | 20200917195519.19589-10-vsementsov@virtuozzo.com |
|---|---|
| State | New |
| Headers | show |
| Series | block: deal with errp: part I | expand |
On Thu 17 Sep 2020 09:55:15 PM CEST, Vladimir Sementsov-Ogievskiy wrote: > It's recommended for bool functions with errp to return true on success > and false on failure. Non-standard interfaces don't help to understand > the code. The change is also needed to reduce error propagation. > > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > +/* > + * Return true on success, false on failure. Anyway, if header_updated > + * provided set it appropriately. > */ I'm not a native speaker but it sounds a bit odd to me. Maybe "If header_updated is not NULL then it is set appropriately regardless of the return value". But I'm fine with your version, so Reviewed-by: Alberto Garcia <berto@igalia.com> Berto
18.09.2020 17:54, Alberto Garcia wrote: > On Thu 17 Sep 2020 09:55:15 PM CEST, Vladimir Sementsov-Ogievskiy wrote: >> It's recommended for bool functions with errp to return true on success >> and false on failure. Non-standard interfaces don't help to understand >> the code. The change is also needed to reduce error propagation. >> >> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > >> +/* >> + * Return true on success, false on failure. Anyway, if header_updated >> + * provided set it appropriately. >> */ > > I'm not a native speaker but it sounds a bit odd to me. Maybe "If > header_updated is not NULL then it is set appropriately regardless of > the return value". That's better I think, thanks. > > But I'm fine with your version, so > > Reviewed-by: Alberto Garcia <berto@igalia.com> > > Berto >
On Thu, 17 Sep 2020 22:55:15 +0300 Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> wrote: > It's recommended for bool functions with errp to return true on success > and false on failure. Non-standard interfaces don't help to understand > the code. The change is also needed to reduce error propagation. > > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > --- With the documentation change suggested by Berto, Reviewed-by: Greg Kurz <groug@kaod.org> > block/qcow2.h | 3 ++- > block/qcow2-bitmap.c | 25 ++++++++++++++----------- > block/qcow2.c | 6 ++---- > 3 files changed, 18 insertions(+), 16 deletions(-) > > diff --git a/block/qcow2.h b/block/qcow2.h > index 6eac088f1c..3c64dcda33 100644 > --- a/block/qcow2.h > +++ b/block/qcow2.h > @@ -972,7 +972,8 @@ void qcow2_cache_discard(Qcow2Cache *c, void *table); > int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res, > void **refcount_table, > int64_t *refcount_table_size); > -bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp); > +bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, bool *header_updated, > + Error **errp); > bool qcow2_get_bitmap_info_list(BlockDriverState *bs, > Qcow2BitmapInfoList **info_list, Error **errp); > int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp); > diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c > index 4f6138f544..500175f4e8 100644 > --- a/block/qcow2-bitmap.c > +++ b/block/qcow2-bitmap.c > @@ -962,25 +962,26 @@ static void set_readonly_helper(gpointer bitmap, gpointer value) > bdrv_dirty_bitmap_set_readonly(bitmap, (bool)value); > } > > -/* qcow2_load_dirty_bitmaps() > - * Return value is a hint for caller: true means that the Qcow2 header was > - * updated. (false doesn't mean that the header should be updated by the > - * caller, it just means that updating was not needed or the image cannot be > - * written to). > - * On failure the function returns false. > +/* > + * Return true on success, false on failure. Anyway, if header_updated > + * provided set it appropriately. > */ > -bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp) > +bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, bool *header_updated, > + Error **errp) > { > BDRVQcow2State *s = bs->opaque; > Qcow2BitmapList *bm_list; > Qcow2Bitmap *bm; > GSList *created_dirty_bitmaps = NULL; > - bool header_updated = false; > bool needs_update = false; > > + if (header_updated) { > + *header_updated = false; > + } > + > if (s->nb_bitmaps == 0) { > /* No bitmaps - nothing to do */ > - return false; > + return true; > } > > bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, > @@ -1036,7 +1037,9 @@ bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp) > error_setg_errno(errp, -ret, "Can't update bitmap directory"); > goto fail; > } > - header_updated = true; > + if (header_updated) { > + *header_updated = true; > + } > } > > if (!can_write(bs)) { > @@ -1047,7 +1050,7 @@ bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp) > g_slist_free(created_dirty_bitmaps); > bitmap_list_free(bm_list); > > - return header_updated; > + return true; > > fail: > g_slist_foreach(created_dirty_bitmaps, release_dirty_bitmap_helper, bs); > diff --git a/block/qcow2.c b/block/qcow2.c > index 8c89c98978..c4b86df7c0 100644 > --- a/block/qcow2.c > +++ b/block/qcow2.c > @@ -1297,7 +1297,6 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options, > unsigned int len, i; > int ret = 0; > QCowHeader header; > - Error *local_err = NULL; > uint64_t ext_end; > uint64_t l1_vm_state_index; > bool update_header = false; > @@ -1785,9 +1784,8 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options, > > if (!(bdrv_get_flags(bs) & BDRV_O_INACTIVE)) { > /* It's case 1, 2 or 3.2. Or 3.1 which is BUG in management layer. */ > - bool header_updated = qcow2_load_dirty_bitmaps(bs, &local_err); > - if (local_err != NULL) { > - error_propagate(errp, local_err); > + bool header_updated; > + if (!qcow2_load_dirty_bitmaps(bs, &header_updated, errp)) { > ret = -EINVAL; > goto fail; > }
diff --git a/block/qcow2.h b/block/qcow2.h index 6eac088f1c..3c64dcda33 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -972,7 +972,8 @@ void qcow2_cache_discard(Qcow2Cache *c, void *table); int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res, void **refcount_table, int64_t *refcount_table_size); -bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp); +bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, bool *header_updated, + Error **errp); bool qcow2_get_bitmap_info_list(BlockDriverState *bs, Qcow2BitmapInfoList **info_list, Error **errp); int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp); diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c index 4f6138f544..500175f4e8 100644 --- a/block/qcow2-bitmap.c +++ b/block/qcow2-bitmap.c @@ -962,25 +962,26 @@ static void set_readonly_helper(gpointer bitmap, gpointer value) bdrv_dirty_bitmap_set_readonly(bitmap, (bool)value); } -/* qcow2_load_dirty_bitmaps() - * Return value is a hint for caller: true means that the Qcow2 header was - * updated. (false doesn't mean that the header should be updated by the - * caller, it just means that updating was not needed or the image cannot be - * written to). - * On failure the function returns false. +/* + * Return true on success, false on failure. Anyway, if header_updated + * provided set it appropriately. */ -bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp) +bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, bool *header_updated, + Error **errp) { BDRVQcow2State *s = bs->opaque; Qcow2BitmapList *bm_list; Qcow2Bitmap *bm; GSList *created_dirty_bitmaps = NULL; - bool header_updated = false; bool needs_update = false; + if (header_updated) { + *header_updated = false; + } + if (s->nb_bitmaps == 0) { /* No bitmaps - nothing to do */ - return false; + return true; } bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, @@ -1036,7 +1037,9 @@ bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp) error_setg_errno(errp, -ret, "Can't update bitmap directory"); goto fail; } - header_updated = true; + if (header_updated) { + *header_updated = true; + } } if (!can_write(bs)) { @@ -1047,7 +1050,7 @@ bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp) g_slist_free(created_dirty_bitmaps); bitmap_list_free(bm_list); - return header_updated; + return true; fail: g_slist_foreach(created_dirty_bitmaps, release_dirty_bitmap_helper, bs); diff --git a/block/qcow2.c b/block/qcow2.c index 8c89c98978..c4b86df7c0 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1297,7 +1297,6 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options, unsigned int len, i; int ret = 0; QCowHeader header; - Error *local_err = NULL; uint64_t ext_end; uint64_t l1_vm_state_index; bool update_header = false; @@ -1785,9 +1784,8 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options, if (!(bdrv_get_flags(bs) & BDRV_O_INACTIVE)) { /* It's case 1, 2 or 3.2. Or 3.1 which is BUG in management layer. */ - bool header_updated = qcow2_load_dirty_bitmaps(bs, &local_err); - if (local_err != NULL) { - error_propagate(errp, local_err); + bool header_updated; + if (!qcow2_load_dirty_bitmaps(bs, &header_updated, errp)) { ret = -EINVAL; goto fail; }
It's recommended for bool functions with errp to return true on success and false on failure. Non-standard interfaces don't help to understand the code. The change is also needed to reduce error propagation. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> --- block/qcow2.h | 3 ++- block/qcow2-bitmap.c | 25 ++++++++++++++----------- block/qcow2.c | 6 ++---- 3 files changed, 18 insertions(+), 16 deletions(-)