Commit f1a4739f authored by Alex Elder's avatar Alex Elder Committed by Sage Weil
Browse files

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: default avatarAlex Elder <elder@inktank.com>
Reviewed-by: default avatarJosh Durgin <josh.durgin@inktank.com>
parent b9434c5b

drivers/block/rbd.c

+66 −20
Original line number Diff line number Diff line
@@ -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;



		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,

			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);

		if (type == OBJ_REQUEST_BIO)

			osd_req_op_extent_osd_data_bio(osd_req, 0,

				obj_request->bio_list, obj_request->length);

					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)

CRA Git | Maintained and supported by SUSTech CRA and CCSE