| Message ID | 519129D1.7050807@inktank.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Reviewed-by: Josh Durgin <josh.durgin@inktank.com> On 05/13/2013 10:58 AM, Alex Elder wrote: > I have inserted this patch into a series I posted over the > weekend to address an issue that Josh's comment raised in > the review for: > [PATCH] rbd: support reading parent page data for writes > This patch, along with the updated series, is available in the > "review/wip-flatten-1" branch of the ceph-client git repository. > > > > > > The code that reads object data from the parent for a copyup on > write request currently assumes that the size of that request is the > size of a "full" object from the original target image. > > That is not necessarily the case. The parent overlap could reduce > the request size below that. To fix that assumption we need to > record the number of pages in the copyup_pages array, for both an > image request and an object request. Rename a local variable in > rbd_img_obj_parent_read_full_callback() to reflect we're recording > the length of the parent read request, not the size of the target > object. > > This resolves: > http://tracker.ceph.com/issues/5038 > > Signed-off-by: Alex Elder <elder@inktank.com> > --- > drivers/block/rbd.c | 31 ++++++++++++++++++++----------- > 1 file changed, 20 insertions(+), 11 deletions(-) > > diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c > index 51c45e7..597b9bb 100644 > --- a/drivers/block/rbd.c > +++ b/drivers/block/rbd.c > @@ -224,6 +224,7 @@ struct rbd_obj_request { > }; > }; > struct page **copyup_pages; > + u32 copyup_page_count; > > struct ceph_osd_request *osd_req; > > @@ -256,6 +257,7 @@ struct rbd_img_request { > struct rbd_obj_request *obj_request; /* obj req initiator */ > }; > struct page **copyup_pages; > + u32 copyup_page_count; > spinlock_t completion_lock;/* protects next_completion */ > u32 next_completion; > rbd_img_callback_t callback; > @@ -2119,7 +2121,7 @@ rbd_img_obj_copyup_callback(struct rbd_obj_request > *obj_request) > { > struct rbd_img_request *img_request; > struct rbd_device *rbd_dev; > - u64 length; > + struct page **pages; > u32 page_count; > > rbd_assert(obj_request->type == OBJ_REQUEST_BIO); > @@ -2129,12 +2131,14 @@ rbd_img_obj_copyup_callback(struct > rbd_obj_request *obj_request) > > rbd_dev = img_request->rbd_dev; > rbd_assert(rbd_dev); > - length = (u64)1 << rbd_dev->header.obj_order; > - page_count = (u32)calc_pages_for(0, length); > > - rbd_assert(obj_request->copyup_pages); > - ceph_release_page_vector(obj_request->copyup_pages, page_count); > + pages = obj_request->copyup_pages; > + rbd_assert(pages != NULL); > obj_request->copyup_pages = NULL; > + page_count = obj_request->copyup_page_count; > + rbd_assert(page_count); > + obj_request->copyup_page_count = 0; > + ceph_release_page_vector(pages, page_count); > > /* > * We want the transfer count to reflect the size of the > @@ -2158,9 +2162,9 @@ rbd_img_obj_parent_read_full_callback(struct > rbd_img_request *img_request) > struct ceph_osd_client *osdc; > struct rbd_device *rbd_dev; > struct page **pages; > + u32 page_count; > int result; > - u64 obj_size; > - u64 xferred; > + u64 parent_length; > > rbd_assert(img_request_child_test(img_request)); > > @@ -2169,19 +2173,21 @@ rbd_img_obj_parent_read_full_callback(struct > rbd_img_request *img_request) > pages = img_request->copyup_pages; > rbd_assert(pages != NULL); > img_request->copyup_pages = NULL; > + page_count = img_request->copyup_page_count; > + rbd_assert(page_count); > + img_request->copyup_page_count = 0; > > orig_request = img_request->obj_request; > rbd_assert(orig_request != NULL); > rbd_assert(orig_request->type == OBJ_REQUEST_BIO); > result = img_request->result; > - obj_size = img_request->length; > - xferred = img_request->xferred; > + parent_length = img_request->length; > + rbd_assert(parent_length == img_request->xferred); > rbd_img_request_put(img_request); > > rbd_assert(orig_request->img_request); > rbd_dev = orig_request->img_request->rbd_dev; > rbd_assert(rbd_dev); > - rbd_assert(obj_size == (u64)1 << rbd_dev->header.obj_order); > > if (result) > goto out_err; > @@ -2195,11 +2201,12 @@ rbd_img_obj_parent_read_full_callback(struct > rbd_img_request *img_request) > goto out_err; > orig_request->osd_req = osd_req; > orig_request->copyup_pages = pages; > + orig_request->copyup_page_count = page_count; > > /* Initialize the copyup op */ > > osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup"); > - osd_req_op_cls_request_data_pages(osd_req, 0, pages, obj_size, 0, > + osd_req_op_cls_request_data_pages(osd_req, 0, pages, parent_length, 0, > false, false); > > /* Then the original write request op */ > @@ -2312,6 +2319,7 @@ static int rbd_img_obj_parent_read_full(struct > rbd_obj_request *obj_request) > if (result) > goto out_err; > parent_request->copyup_pages = pages; > + parent_request->copyup_page_count = page_count; > > parent_request->callback = rbd_img_obj_parent_read_full_callback; > result = rbd_img_request_submit(parent_request); > @@ -2319,6 +2327,7 @@ static int rbd_img_obj_parent_read_full(struct > rbd_obj_request *obj_request) > return 0; > > parent_request->copyup_pages = NULL; > + parent_request->copyup_page_count = 0; > parent_request->obj_request = NULL; > rbd_obj_request_put(obj_request); > out_err: > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 51c45e7..597b9bb 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -224,6 +224,7 @@ struct rbd_obj_request { }; }; struct page **copyup_pages; + u32 copyup_page_count; struct ceph_osd_request *osd_req; @@ -256,6 +257,7 @@ struct rbd_img_request { struct rbd_obj_request *obj_request; /* obj req initiator */ }; struct page **copyup_pages; + u32 copyup_page_count; spinlock_t completion_lock;/* protects next_completion */ u32 next_completion; rbd_img_callback_t callback; @@ -2119,7 +2121,7 @@ rbd_img_obj_copyup_callback(struct rbd_obj_request *obj_request) { struct rbd_img_request *img_request; struct rbd_device *rbd_dev; - u64 length; + struct page **pages; u32 page_count;
I have inserted this patch into a series I posted over the weekend to address an issue that Josh's comment raised in the review for: [PATCH] rbd: support reading parent page data for writes This patch, along with the updated series, is available in the "review/wip-flatten-1" branch of the ceph-client git repository. The code that reads object data from the parent for a copyup on write request currently assumes that the size of that request is the size of a "full" object from the original target image. That is not necessarily the case. The parent overlap could reduce the request size below that. To fix that assumption we need to record the number of pages in the copyup_pages array, for both an image request and an object request. Rename a local variable in rbd_img_obj_parent_read_full_callback() to reflect we're recording the length of the parent read request, not the size of the target object. This resolves: http://tracker.ceph.com/issues/5038 Signed-off-by: Alex Elder <elder@inktank.com> --- drivers/block/rbd.c | 31 ++++++++++++++++++++----------- 1 file changed, 20 insertions(+), 11 deletions(-) rbd_assert(obj_request->type == OBJ_REQUEST_BIO); @@ -2129,12 +2131,14 @@ rbd_img_obj_copyup_callback(struct rbd_obj_request *obj_request) rbd_dev = img_request->rbd_dev; rbd_assert(rbd_dev); - length = (u64)1 << rbd_dev->header.obj_order; - page_count = (u32)calc_pages_for(0, length); - rbd_assert(obj_request->copyup_pages); - ceph_release_page_vector(obj_request->copyup_pages, page_count); + pages = obj_request->copyup_pages; + rbd_assert(pages != NULL); obj_request->copyup_pages = NULL; + page_count = obj_request->copyup_page_count; + rbd_assert(page_count); + obj_request->copyup_page_count = 0; + ceph_release_page_vector(pages, page_count); /* * We want the transfer count to reflect the size of the @@ -2158,9 +2162,9 @@ rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request) struct ceph_osd_client *osdc; struct rbd_device *rbd_dev; struct page **pages; + u32 page_count; int result; - u64 obj_size; - u64 xferred; + u64 parent_length; rbd_assert(img_request_child_test(img_request)); @@ -2169,19 +2173,21 @@ rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request) pages = img_request->copyup_pages; rbd_assert(pages != NULL); img_request->copyup_pages = NULL; + page_count = img_request->copyup_page_count; + rbd_assert(page_count); + img_request->copyup_page_count = 0; orig_request = img_request->obj_request; rbd_assert(orig_request != NULL); rbd_assert(orig_request->type == OBJ_REQUEST_BIO); result = img_request->result; - obj_size = img_request->length; - xferred = img_request->xferred; + parent_length = img_request->length; + rbd_assert(parent_length == img_request->xferred); rbd_img_request_put(img_request); rbd_assert(orig_request->img_request); rbd_dev = orig_request->img_request->rbd_dev; rbd_assert(rbd_dev); - rbd_assert(obj_size == (u64)1 << rbd_dev->header.obj_order); if (result) goto out_err; @@ -2195,11 +2201,12 @@ rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request) goto out_err; orig_request->osd_req = osd_req; orig_request->copyup_pages = pages; + orig_request->copyup_page_count = page_count; /* Initialize the copyup op */ osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup"); - osd_req_op_cls_request_data_pages(osd_req, 0, pages, obj_size, 0, + osd_req_op_cls_request_data_pages(osd_req, 0, pages, parent_length, 0, false, false); /* Then the original write request op */ @@ -2312,6 +2319,7 @@ static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request) if (result) goto out_err; parent_request->copyup_pages = pages; + parent_request->copyup_page_count = page_count; parent_request->callback = rbd_img_obj_parent_read_full_callback; result = rbd_img_request_submit(parent_request); @@ -2319,6 +2327,7 @@ static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request) return 0; parent_request->copyup_pages = NULL; + parent_request->copyup_page_count = 0; parent_request->obj_request = NULL; rbd_obj_request_put(obj_request); out_err: