From f1a4739f333b519fe041e1ad81d9b31c94b9d6a3 Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Fri, 19 Apr 2013 15:34:50 -0500 Subject: [PATCH] rbd: support page array image requests This patch adds the ability to build an image request whose data will be written from or read into memory described by a page array. (Previously only bio lists were supported.) Originally this was going to define a new function for this purpose but it was largely identical to the rbd_img_request_fill_bio(). So instead, rbd_img_request_fill_bio() has been generalized to handle both types of image request. For the moment we still only fill image requests with bio data. Signed-off-by: Alex Elder Reviewed-by: Josh Durgin --- drivers/block/rbd.c | 86 ++++++++++++++++++++++++++++++++++----------- 1 file changed, 66 insertions(+), 20 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 06bbd55c0ea1..8a7216d784d7 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -1780,6 +1780,13 @@ static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request) img_request->result = result; } + /* Image object requests don't own their page array */ + + if (obj_request->type == OBJ_REQUEST_PAGES) { + obj_request->pages = NULL; + obj_request->page_count = 0; + } + if (img_request_child_test(img_request)) { rbd_assert(img_request->obj_request != NULL); more = obj_request->which < img_request->obj_request_count - 1; @@ -1830,30 +1837,48 @@ out: rbd_img_request_complete(img_request); } -static int rbd_img_request_fill_bio(struct rbd_img_request *img_request, - struct bio *bio_list) +/* + * Split up an image request into one or more object requests, each + * to a different object. The "type" parameter indicates whether + * "data_desc" is the pointer to the head of a list of bio + * structures, or the base of a page array. In either case this + * function assumes data_desc describes memory sufficient to hold + * all data described by the image request. + */ +static int rbd_img_request_fill(struct rbd_img_request *img_request, + enum obj_request_type type, + void *data_desc) { struct rbd_device *rbd_dev = img_request->rbd_dev; struct rbd_obj_request *obj_request = NULL; struct rbd_obj_request *next_obj_request; bool write_request = img_request_write_test(img_request); - unsigned int bio_offset; + struct bio *bio_list; + unsigned int bio_offset = 0; + struct page **pages; u64 img_offset; u64 resid; u16 opcode; - dout("%s: img %p bio %p\n", __func__, img_request, bio_list); + dout("%s: img %p type %d data_desc %p\n", __func__, img_request, + (int)type, data_desc); opcode = write_request ? CEPH_OSD_OP_WRITE : CEPH_OSD_OP_READ; - bio_offset = 0; img_offset = img_request->offset; - rbd_assert(img_offset == bio_list->bi_sector << SECTOR_SHIFT); resid = img_request->length; rbd_assert(resid > 0); + + if (type == OBJ_REQUEST_BIO) { + bio_list = data_desc; + rbd_assert(img_offset == bio_list->bi_sector << SECTOR_SHIFT); + } else { + rbd_assert(type == OBJ_REQUEST_PAGES); + pages = data_desc; + } + while (resid) { struct ceph_osd_request *osd_req; const char *object_name; - unsigned int clone_size; u64 offset; u64 length; @@ -1863,19 +1888,33 @@ static int rbd_img_request_fill_bio(struct rbd_img_request *img_request, offset = rbd_segment_offset(rbd_dev, img_offset); length = rbd_segment_length(rbd_dev, img_offset, resid); obj_request = rbd_obj_request_create(object_name, - offset, length, - OBJ_REQUEST_BIO); + offset, length, type); kfree(object_name); /* object request has its own copy */ if (!obj_request) goto out_unwind; - rbd_assert(length <= (u64) UINT_MAX); - clone_size = (unsigned int) length; - obj_request->bio_list = bio_chain_clone_range(&bio_list, - &bio_offset, clone_size, - GFP_ATOMIC); - if (!obj_request->bio_list) - goto out_partial; + if (type == OBJ_REQUEST_BIO) { + unsigned int clone_size; + + rbd_assert(length <= (u64)UINT_MAX); + clone_size = (unsigned int)length; + obj_request->bio_list = + bio_chain_clone_range(&bio_list, + &bio_offset, + clone_size, + GFP_ATOMIC); + if (!obj_request->bio_list) + goto out_partial; + } else { + unsigned int page_count; + + obj_request->pages = pages; + page_count = (u32)calc_pages_for(offset, length); + obj_request->page_count = page_count; + if ((offset + length) & ~PAGE_MASK) + page_count--; /* more on last page */ + pages += page_count; + } osd_req = rbd_osd_req_create(rbd_dev, write_request, obj_request); @@ -1886,8 +1925,13 @@ static int rbd_img_request_fill_bio(struct rbd_img_request *img_request, osd_req_op_extent_init(osd_req, 0, opcode, offset, length, 0, 0); - osd_req_op_extent_osd_data_bio(osd_req, 0, - obj_request->bio_list, obj_request->length); + if (type == OBJ_REQUEST_BIO) + osd_req_op_extent_osd_data_bio(osd_req, 0, + obj_request->bio_list, length); + else + osd_req_op_extent_osd_data_pages(osd_req, 0, + obj_request->pages, length, + offset & ~PAGE_MASK, false, false); if (write_request) rbd_osd_req_format_write(obj_request); @@ -2120,7 +2164,8 @@ static void rbd_img_parent_read(struct rbd_obj_request *obj_request) rbd_obj_request_get(obj_request); img_request->obj_request = obj_request; - result = rbd_img_request_fill_bio(img_request, obj_request->bio_list); + result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO, + obj_request->bio_list); if (result) goto out_err; @@ -2425,7 +2470,8 @@ static void rbd_request_fn(struct request_queue *q) img_request->rq = rq; - result = rbd_img_request_fill_bio(img_request, rq->bio); + result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO, + rq->bio); if (!result) result = rbd_img_request_submit(img_request); if (result) -- 2.30.2