rbd: switch to common striping framework

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index fc94e2c..24f169f 100644 (file)
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -1326,7 +1326,6 @@ static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
        obj_request->img_request = img_request;
        img_request->obj_request_count++;
        img_request->pending_count++;
-       list_add_tail(&obj_request->ex.oe_item, &img_request->object_extents);
        dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
 }
 
@@ -2055,6 +2054,158 @@ out_unwind:
        return -ENOMEM;
 }
 
+union rbd_img_fill_iter {
+       struct ceph_bio_iter    bio_iter;
+       struct ceph_bvec_iter   bvec_iter;
+};
+
+struct rbd_img_fill_ctx {
+       enum obj_request_type   pos_type;
+       union rbd_img_fill_iter *pos;
+       union rbd_img_fill_iter iter;
+       ceph_object_extent_fn_t set_pos_fn;
+};
+
+static struct ceph_object_extent *alloc_object_extent(void *arg)
+{
+       struct rbd_img_request *img_req = arg;
+       struct rbd_obj_request *obj_req;
+
+       obj_req = rbd_obj_request_create();
+       if (!obj_req)
+               return NULL;
+
+       rbd_img_obj_request_add(img_req, obj_req);
+       return &obj_req->ex;
+}
+
+/*
+ * Map a list of image extents to a list of object extents, create the
+ * corresponding object requests (normally each to a different object,
+ * but not always) and add them to @img_req.  For each object request,
+ * set up its data descriptor to point to the corresponding chunk of
+ * @fctx->pos data buffer.
+ *
+ * @fctx->pos data buffer is assumed to be large enough.
+ */
+static int rbd_img_fill_request(struct rbd_img_request *img_req,
+                               struct ceph_file_extent *img_extents,
+                               u32 num_img_extents,
+                               struct rbd_img_fill_ctx *fctx)
+{
+       u32 i;
+       int ret;
+
+       img_req->data_type = fctx->pos_type;
+
+       /*
+        * Create object requests and set each object request's starting
+        * position in the provided bio (list) or bio_vec array.
+        */
+       fctx->iter = *fctx->pos;
+       for (i = 0; i < num_img_extents; i++) {
+               ret = ceph_file_to_extents(&img_req->rbd_dev->layout,
+                                          img_extents[i].fe_off,
+                                          img_extents[i].fe_len,
+                                          &img_req->object_extents,
+                                          alloc_object_extent, img_req,
+                                          fctx->set_pos_fn, &fctx->iter);
+               if (ret)
+                       return ret;
+       }
+
+       return __rbd_img_fill_request(img_req);
+}
+
+static int rbd_img_fill_nodata(struct rbd_img_request *img_req,
+                              u64 off, u64 len)
+{
+       struct ceph_file_extent ex = { off, len };
+       union rbd_img_fill_iter dummy;
+       struct rbd_img_fill_ctx fctx = {
+               .pos_type = OBJ_REQUEST_NODATA,
+               .pos = &dummy,
+       };
+
+       return rbd_img_fill_request(img_req, &ex, 1, &fctx);
+}
+
+static void set_bio_pos(struct ceph_object_extent *ex, u32 bytes, void *arg)
+{
+       struct rbd_obj_request *obj_req =
+           container_of(ex, struct rbd_obj_request, ex);
+       struct ceph_bio_iter *it = arg;
+
+       dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
+       obj_req->bio_pos = *it;
+       ceph_bio_iter_advance(it, bytes);
+}
+
+static int __rbd_img_fill_from_bio(struct rbd_img_request *img_req,
+                                  struct ceph_file_extent *img_extents,
+                                  u32 num_img_extents,
+                                  struct ceph_bio_iter *bio_pos)
+{
+       struct rbd_img_fill_ctx fctx = {
+               .pos_type = OBJ_REQUEST_BIO,
+               .pos = (union rbd_img_fill_iter *)bio_pos,
+               .set_pos_fn = set_bio_pos,
+       };
+
+       return rbd_img_fill_request(img_req, img_extents, num_img_extents,
+                                   &fctx);
+}
+
+static int rbd_img_fill_from_bio(struct rbd_img_request *img_req,
+                                u64 off, u64 len, struct bio *bio)
+{
+       struct ceph_file_extent ex = { off, len };
+       struct ceph_bio_iter it = { .bio = bio, .iter = bio->bi_iter };
+
+       return __rbd_img_fill_from_bio(img_req, &ex, 1, &it);
+}
+
+static void set_bvec_pos(struct ceph_object_extent *ex, u32 bytes, void *arg)
+{
+       struct rbd_obj_request *obj_req =
+           container_of(ex, struct rbd_obj_request, ex);
+       struct ceph_bvec_iter *it = arg;
+
+       obj_req->bvec_pos = *it;
+       ceph_bvec_iter_shorten(&obj_req->bvec_pos, bytes);
+       ceph_bvec_iter_advance(it, bytes);
+}
+
+static int __rbd_img_fill_from_bvecs(struct rbd_img_request *img_req,
+                                    struct ceph_file_extent *img_extents,
+                                    u32 num_img_extents,
+                                    struct ceph_bvec_iter *bvec_pos)
+{
+       struct rbd_img_fill_ctx fctx = {
+               .pos_type = OBJ_REQUEST_BVECS,
+               .pos = (union rbd_img_fill_iter *)bvec_pos,
+               .set_pos_fn = set_bvec_pos,
+       };
+
+       return rbd_img_fill_request(img_req, img_extents, num_img_extents,
+                                   &fctx);
+}
+
+static int rbd_img_fill_from_bvecs(struct rbd_img_request *img_req,
+                                  struct ceph_file_extent *img_extents,
+                                  u32 num_img_extents,
+                                  struct bio_vec *bvecs)
+{
+       struct ceph_bvec_iter it = {
+               .bvecs = bvecs,
+               .iter = { .bi_size = ceph_file_extents_bytes(img_extents,
+                                                            num_img_extents) },
+       };
+
+       return __rbd_img_fill_from_bvecs(img_req, img_extents, num_img_extents,
+                                        &it);
+}
+
 static void rbd_img_request_submit(struct rbd_img_request *img_request)
 {
        struct rbd_obj_request *obj_request;
@@ -2083,26 +2234,25 @@ static int rbd_obj_read_from_parent(struct rbd_obj_request *obj_req)
        if (!rbd_img_is_write(img_req)) {
                switch (img_req->data_type) {
                case OBJ_REQUEST_BIO:
-                       ret = rbd_img_request_fill(child_img_req,
-                                                  OBJ_REQUEST_BIO,
-                                                  &obj_req->bio_pos);
+                       ret = __rbd_img_fill_from_bio(child_img_req,
+                                                     obj_req->img_extents,
+                                                     obj_req->num_img_extents,
+                                                     &obj_req->bio_pos);
                        break;
                case OBJ_REQUEST_BVECS:
-                       ret = rbd_img_request_fill(child_img_req,
-                                                  OBJ_REQUEST_BVECS,
-                                                  &obj_req->bvec_pos);
+                       ret = __rbd_img_fill_from_bvecs(child_img_req,
+                                                     obj_req->img_extents,
+                                                     obj_req->num_img_extents,
+                                                     &obj_req->bvec_pos);
                        break;
                default:
                        rbd_assert(0);
                }
        } else {
-               struct ceph_bvec_iter it = {
-                       .bvecs = obj_req->copyup_bvecs,
-                       .iter = { .bi_size = obj_req->img_extents[0].fe_len },
-               };
-
-               ret = rbd_img_request_fill(child_img_req, OBJ_REQUEST_BVECS,
-                                          &it);
+               ret = rbd_img_fill_from_bvecs(child_img_req,
+                                             obj_req->img_extents,
+                                             obj_req->num_img_extents,
+                                             obj_req->copyup_bvecs);
        }
        if (ret) {
                rbd_img_request_put(child_img_req);
@@ -3520,15 +3670,10 @@ static void rbd_queue_workfn(struct work_struct *work)
        snapc = NULL; /* img_request consumes a ref */
 
        if (op_type == OBJ_OP_DISCARD)
-               result = rbd_img_request_fill(img_request, OBJ_REQUEST_NODATA,
-                                             NULL);
-       else {
-               struct ceph_bio_iter bio_it = { .bio = rq->bio,
-                                               .iter = rq->bio->bi_iter };
-
-               result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
-                                             &bio_it);
-       }
+               result = rbd_img_fill_nodata(img_request, offset, length);
+       else
+               result = rbd_img_fill_from_bio(img_request, offset, length,
+                                              rq->bio);
        if (result)
                goto err_img_request;