From 5a237819aa4e0421a17966e9baf91b9caedaf61d Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Tue, 6 Feb 2018 19:26:34 +0100 Subject: [PATCH] rbd: switch to common striping framework Signed-off-by: Ilya Dryomov --- drivers/block/rbd.c | 191 ++++++++++++++++++++++++++++++++++++++------ 1 file changed, 168 insertions(+), 23 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index fc94e2c45e28..24f169f33219 100644 --- 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 @@ static int rbd_img_request_fill(struct rbd_img_request *img_request, 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;