| Message ID | 20220113144426.4036493-3-pl@kamp.de |
|---|---|
| State | New |
| Headers | show |
| Series | fixes for bdrv_co_block_status | expand |
On Thu, Jan 13, 2022 at 3:44 PM Peter Lieven <pl@kamp.de> wrote: > > librbd had a bug until early 2022 that affected all versions of ceph that > supported fast-diff. This bug results in reporting of incorrect offsets > if the offset parameter to rbd_diff_iterate2 is not object aligned. > > This patch works around this bug for pre Quincy versions of librbd. > > Cc: qemu-stable@nongnu.org > Signed-off-by: Peter Lieven <pl@kamp.de> > --- > block/rbd.c | 42 ++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 40 insertions(+), 2 deletions(-) > > diff --git a/block/rbd.c b/block/rbd.c > index 20bb896c4a..d174d51659 100644 > --- a/block/rbd.c > +++ b/block/rbd.c > @@ -1320,6 +1320,7 @@ static int coroutine_fn qemu_rbd_co_block_status(BlockDriverState *bs, > int status, r; > RBDDiffIterateReq req = { .offs = offset }; > uint64_t features, flags; > + uint64_t head = 0; > > assert(offset + bytes <= s->image_size); > > @@ -1347,7 +1348,43 @@ static int coroutine_fn qemu_rbd_co_block_status(BlockDriverState *bs, > return status; > } > > - r = rbd_diff_iterate2(s->image, NULL, offset, bytes, true, true, > +#if LIBRBD_VERSION_CODE < LIBRBD_VERSION(1, 17, 0) > + /* > + * librbd had a bug until early 2022 that affected all versions of ceph that > + * supported fast-diff. This bug results in reporting of incorrect offsets > + * if the offset parameter to rbd_diff_iterate2 is not object aligned. > + * Work around this bug by rounding down the offset to object boundaries. > + * This is OK because we call rbd_diff_iterate2 with whole_object = true. > + * However, this workaround only works for non cloned images with default > + * striping. > + * > + * See: https://tracker.ceph.com/issues/53784 > + */ > + > + /* check if RBD image has non-default striping enabled */ Nit: extra space Thanks, Ilya
On Thu, Jan 13, 2022 at 03:44:26PM +0100, Peter Lieven wrote: >librbd had a bug until early 2022 that affected all versions of ceph that >supported fast-diff. This bug results in reporting of incorrect offsets >if the offset parameter to rbd_diff_iterate2 is not object aligned. > >This patch works around this bug for pre Quincy versions of librbd. > I'm not sure, but maybe we could add the fixes tag also to this patch, since without this workaround we can have issues with buggy librbd. Fixes: 0347a8fd4c3faaedf119be04c197804be40a384b >Cc: qemu-stable@nongnu.org >Signed-off-by: Peter Lieven <pl@kamp.de> >--- > block/rbd.c | 42 ++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 40 insertions(+), 2 deletions(-) Tested-by: Stefano Garzarella <sgarzare@redhat.com> > >diff --git a/block/rbd.c b/block/rbd.c >index 20bb896c4a..d174d51659 100644 >--- a/block/rbd.c >+++ b/block/rbd.c >@@ -1320,6 +1320,7 @@ static int coroutine_fn qemu_rbd_co_block_status(BlockDriverState *bs, > int status, r; > RBDDiffIterateReq req = { .offs = offset }; > uint64_t features, flags; >+ uint64_t head = 0; > > assert(offset + bytes <= s->image_size); > >@@ -1347,7 +1348,43 @@ static int coroutine_fn qemu_rbd_co_block_status(BlockDriverState *bs, > return status; > } > >- r = rbd_diff_iterate2(s->image, NULL, offset, bytes, true, true, >+#if LIBRBD_VERSION_CODE < LIBRBD_VERSION(1, 17, 0) >+ /* >+ * librbd had a bug until early 2022 that affected all versions of ceph that >+ * supported fast-diff. This bug results in reporting of incorrect offsets >+ * if the offset parameter to rbd_diff_iterate2 is not object aligned. >+ * Work around this bug by rounding down the offset to object boundaries. >+ * This is OK because we call rbd_diff_iterate2 with whole_object = true. >+ * However, this workaround only works for non cloned images with default >+ * striping. >+ * >+ * See: https://tracker.ceph.com/issues/53784 >+ */ >+ >+ /* check if RBD image has non-default striping enabled */ >+ if (features & RBD_FEATURE_STRIPINGV2) { >+ return status; >+ } >+ >+#pragma GCC diagnostic push >+#pragma GCC diagnostic ignored "-Wdeprecated-declarations" >+ /* >+ * check if RBD image is a clone (= has a parent). >+ * >+ * rbd_get_parent_info is deprecated from Nautilus onwards, but the >+ * replacement rbd_get_parent is not present in Luminous and Mimic. >+ */ >+ if (rbd_get_parent_info(s->image, NULL, 0, NULL, 0, NULL, 0) != -ENOENT) { >+ return status; >+ } >+#pragma GCC diagnostic pop >+ >+ head = req.offs & (s->object_size - 1); >+ req.offs -= head; >+ bytes += head; >+#endif >+ >+ r = rbd_diff_iterate2(s->image, NULL, req.offs, bytes, true, true, > qemu_rbd_diff_iterate_cb, &req); > if (r < 0 && r != QEMU_RBD_EXIT_DIFF_ITERATE2) { > return status; >@@ -1366,7 +1403,8 @@ static int coroutine_fn qemu_rbd_co_block_status(BlockDriverState *bs, > status = BDRV_BLOCK_ZERO | BDRV_BLOCK_OFFSET_VALID; > } > >- *pnum = req.bytes; >+ assert(req.bytes > head); >+ *pnum = req.bytes - head; > return status; > } > >-- >2.25.1 > > >
diff --git a/block/rbd.c b/block/rbd.c index 20bb896c4a..d174d51659 100644 --- a/block/rbd.c +++ b/block/rbd.c @@ -1320,6 +1320,7 @@ static int coroutine_fn qemu_rbd_co_block_status(BlockDriverState *bs, int status, r; RBDDiffIterateReq req = { .offs = offset }; uint64_t features, flags; + uint64_t head = 0; assert(offset + bytes <= s->image_size); @@ -1347,7 +1348,43 @@ static int coroutine_fn qemu_rbd_co_block_status(BlockDriverState *bs, return status; } - r = rbd_diff_iterate2(s->image, NULL, offset, bytes, true, true, +#if LIBRBD_VERSION_CODE < LIBRBD_VERSION(1, 17, 0) + /* + * librbd had a bug until early 2022 that affected all versions of ceph that + * supported fast-diff. This bug results in reporting of incorrect offsets + * if the offset parameter to rbd_diff_iterate2 is not object aligned. + * Work around this bug by rounding down the offset to object boundaries. + * This is OK because we call rbd_diff_iterate2 with whole_object = true. + * However, this workaround only works for non cloned images with default + * striping. + * + * See: https://tracker.ceph.com/issues/53784 + */ + + /* check if RBD image has non-default striping enabled */ + if (features & RBD_FEATURE_STRIPINGV2) { + return status; + } + +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wdeprecated-declarations" + /* + * check if RBD image is a clone (= has a parent). + * + * rbd_get_parent_info is deprecated from Nautilus onwards, but the + * replacement rbd_get_parent is not present in Luminous and Mimic. + */ + if (rbd_get_parent_info(s->image, NULL, 0, NULL, 0, NULL, 0) != -ENOENT) { + return status; + } +#pragma GCC diagnostic pop + + head = req.offs & (s->object_size - 1); + req.offs -= head; + bytes += head; +#endif + + r = rbd_diff_iterate2(s->image, NULL, req.offs, bytes, true, true, qemu_rbd_diff_iterate_cb, &req); if (r < 0 && r != QEMU_RBD_EXIT_DIFF_ITERATE2) { return status; @@ -1366,7 +1403,8 @@ static int coroutine_fn qemu_rbd_co_block_status(BlockDriverState *bs, status = BDRV_BLOCK_ZERO | BDRV_BLOCK_OFFSET_VALID; } - *pnum = req.bytes; + assert(req.bytes > head); + *pnum = req.bytes - head; return status; }
librbd had a bug until early 2022 that affected all versions of ceph that supported fast-diff. This bug results in reporting of incorrect offsets if the offset parameter to rbd_diff_iterate2 is not object aligned. This patch works around this bug for pre Quincy versions of librbd. Cc: qemu-stable@nongnu.org Signed-off-by: Peter Lieven <pl@kamp.de> --- block/rbd.c | 42 ++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 40 insertions(+), 2 deletions(-)