libosd: scatter gather commands and stuff for 2.6.37

index e88bbdd..771ab12 100644
@@ -1218,17 +1218,18 @@ int osd_req_add_get_attr_page(struct osd_request *or,
 	or->get_attr.buff = attar_page;
 	or->get_attr.total_bytes = max_page_len;
 
-	or->set_attr.buff = set_one_attr->val_ptr;
-	or->set_attr.total_bytes = set_one_attr->len;
-
 	cdbh->attrs_page.get_attr_page = cpu_to_be32(page_id);
 	cdbh->attrs_page.get_attr_alloc_length = cpu_to_be32(max_page_len);
-	/* ocdb->attrs_page.get_attr_offset; */
+
+	if (!set_one_attr || !set_one_attr->attr_page)
+		return 0; /* The set is optional */
+
+	or->set_attr.buff = set_one_attr->val_ptr;
+	or->set_attr.total_bytes = set_one_attr->len;
 
 	cdbh->attrs_page.set_attr_page = cpu_to_be32(set_one_attr->attr_page);
 	cdbh->attrs_page.set_attr_id = cpu_to_be32(set_one_attr->attr_id);
 	cdbh->attrs_page.set_attr_length = cpu_to_be32(set_one_attr->len);
-	/* ocdb->attrs_page.set_attr_offset; */
 	return 0;
 }
 EXPORT_SYMBOL(osd_req_add_get_attr_page);

@@ -1248,11 +1249,14 @@ static int _osd_req_finalize_attr_page(struct osd_request *or)
 	if (ret)
 		return ret;
 
+	if (or->set_attr.total_bytes == 0)
+		return 0;
+
 	/* set one value */
 	cdbh->attrs_page.set_attr_offset =
 		osd_req_encode_offset(or, or->out.total_bytes, &out_padding);
 
-	ret = _req_append_segment(or, out_padding, &or->enc_get_attr, NULL,
+	ret = _req_append_segment(or, out_padding, &or->set_attr, NULL,
 				  &or->out);
 	return ret;
 }

index 771ab12..acbdcb6 100644
@@ -452,10 +452,6 @@ void osd_end_request(struct osd_request *or)
 {
 	struct request *rq = or->request;
 
-	_osd_free_seg(or, &or->set_attr);
-	_osd_free_seg(or, &or->enc_get_attr);
-	_osd_free_seg(or, &or->get_attr);
-
 	if (rq) {
 		if (rq->next_rq) {
 			_put_request(rq->next_rq);

@@ -464,6 +460,11 @@ void osd_end_request(struct osd_request *or)
 
 		_put_request(rq);
 	}
+
+	_osd_free_seg(or, &or->get_attr);
+	_osd_free_seg(or, &or->enc_get_attr);
+	_osd_free_seg(or, &or->set_attr);
+
 	_osd_request_free(or);
 }
 EXPORT_SYMBOL(osd_end_request);

index acbdcb6..f5b5735 100644
@@ -464,6 +464,7 @@ void osd_end_request(struct osd_request *or)
 	_osd_free_seg(or, &or->get_attr);
 	_osd_free_seg(or, &or->enc_get_attr);
 	_osd_free_seg(or, &or->set_attr);
+	_osd_free_seg(or, &or->cdb_cont);
 
 	_osd_request_free(or);
 }

@@ -548,6 +549,12 @@ static int _osd_realloc_seg(struct osd_request *or,
 	return 0;
 }
 
+static int _alloc_cdb_cont(struct osd_request *or, unsigned total_bytes)
+{
+	OSD_DEBUG("total_bytes=%d\n", total_bytes);
+	return _osd_realloc_seg(or, &or->cdb_cont, total_bytes);
+}
+
 static int _alloc_set_attr_list(struct osd_request *or,
 	const struct osd_attr *oa, unsigned nelem, unsigned add_bytes)
 {

@@ -886,6 +893,128 @@ int osd_req_read_kern(struct osd_request *or,
 }
 EXPORT_SYMBOL(osd_req_read_kern);
 
+static int _add_sg_continuation_descriptor(struct osd_request *or,
+	const struct osd_sg_entry *sglist, unsigned numentries, u64 *len)
+{
+	struct osd_sg_continuation_descriptor *oscd;
+	u32 oscd_size;
+	unsigned i;
+	int ret;
+
+	oscd_size = sizeof(*oscd) + numentries * sizeof(oscd->entries[0]);
+
+	if (!or->cdb_cont.total_bytes) {
+		/* First time, jump over the header, we will write to:
+		 *	cdb_cont.buff + cdb_cont.total_bytes
+		 */
+		or->cdb_cont.total_bytes =
+				sizeof(struct osd_continuation_segment_header);
+	}
+
+	ret = _alloc_cdb_cont(or, or->cdb_cont.total_bytes + oscd_size);
+	if (unlikely(ret))
+		return ret;
+
+	oscd = or->cdb_cont.buff + or->cdb_cont.total_bytes;
+	oscd->hdr.type = cpu_to_be16(SCATTER_GATHER_LIST);
+	oscd->hdr.pad_length = 0;
+	oscd->hdr.length = cpu_to_be32(oscd_size - sizeof(*oscd));
+
+	*len = 0;
+	/* copy the sg entries and convert to network byte order */
+	for (i = 0; i < numentries; i++) {
+		oscd->entries[i].offset = cpu_to_be64(sglist[i].offset);
+		oscd->entries[i].len    = cpu_to_be64(sglist[i].len);
+		*len += sglist[i].len;
+	}
+
+	or->cdb_cont.total_bytes += oscd_size;
+	OSD_DEBUG("total_bytes=%d oscd_size=%d numentries=%d\n",
+		  or->cdb_cont.total_bytes, oscd_size, numentries);
+	return 0;
+}
+
+static int _osd_req_finalize_cdb_cont(struct osd_request *or, const u8 *cap_key)
+{
+	struct request_queue *req_q = osd_request_queue(or->osd_dev);
+	struct bio *bio;
+	struct osd_cdb_head *cdbh = osd_cdb_head(&or->cdb);
+	struct osd_continuation_segment_header *cont_seg_hdr;
+
+	if (!or->cdb_cont.total_bytes)
+		return 0;
+
+	cont_seg_hdr = or->cdb_cont.buff;
+	cont_seg_hdr->format = CDB_CONTINUATION_FORMAT_V2;
+	cont_seg_hdr->service_action = cdbh->varlen_cdb.service_action;
+
+	/* create a bio for continuation segment */
+	bio = bio_map_kern(req_q, or->cdb_cont.buff, or->cdb_cont.total_bytes,
+			   GFP_KERNEL);
+	if (unlikely(!bio))
+		return -ENOMEM;
+
+	bio->bi_rw |= REQ_WRITE;
+
+	/* integrity check the continuation before the bio is linked
+	 * with the other data segments since the continuation
+	 * integrity is separate from the other data segments.
+	 */
+	osd_sec_sign_data(cont_seg_hdr->integrity_check, bio, cap_key);
+
+	cdbh->v2.cdb_continuation_length = cpu_to_be32(or->cdb_cont.total_bytes);
+
+	/* we can't use _req_append_segment, because we need to link in the
+	 * continuation bio to the head of the bio list - the
+	 * continuation segment (if it exists) is always the first segment in
+	 * the out data buffer.
+	 */
+	bio->bi_next = or->out.bio;
+	or->out.bio = bio;
+	or->out.total_bytes += or->cdb_cont.total_bytes;
+
+	return 0;
+}
+
+/* osd_req_write_sg: Takes a @bio that points to the data out buffer and an
+ * @sglist that has the scatter gather entries. Scatter-gather enables a write
+ * of multiple none-contiguous areas of an object, in a single call. The extents
+ * may overlap and/or be in any order. The only constrain is that:
+ *	total_bytes(sglist) >= total_bytes(bio)
+ */
+int osd_req_write_sg(struct osd_request *or,
+	const struct osd_obj_id *obj, struct bio *bio,
+	const struct osd_sg_entry *sglist, unsigned numentries)
+{
+	u64 len;
+	int ret = _add_sg_continuation_descriptor(or, sglist, numentries, &len);
+
+	if (ret)
+		return ret;
+	osd_req_write(or, obj, 0, bio, len);
+
+	return 0;
+}
+EXPORT_SYMBOL(osd_req_write_sg);
+
+/* osd_req_read_sg: Read multiple extents of an object into @bio
+ * See osd_req_write_sg
+ */
+int osd_req_read_sg(struct osd_request *or,
+	const struct osd_obj_id *obj, struct bio *bio,
+	const struct osd_sg_entry *sglist, unsigned numentries)
+{
+	u64 len;
+	int ret = _add_sg_continuation_descriptor(or, sglist, numentries, &len);
+
+	if (ret)
+		return ret;
+	osd_req_read(or, obj, 0, bio, len);
+
+	return 0;
+}
+EXPORT_SYMBOL(osd_req_read_sg);
+
 void osd_req_get_attributes(struct osd_request *or,
 	const struct osd_obj_id *obj)
 {

@@ -1281,7 +1410,8 @@ static inline void osd_sec_parms_set_in_offset(bool is_v1,
 }
 
 static int _osd_req_finalize_data_integrity(struct osd_request *or,
-	bool has_in, bool has_out, u64 out_data_bytes, const u8 *cap_key)
+	bool has_in, bool has_out, struct bio *out_data_bio, u64 out_data_bytes,
+	const u8 *cap_key)
 {
 	struct osd_security_parameters *sec_parms = _osd_req_sec_params(or);
 	int ret;

@@ -1312,7 +1442,7 @@ static int _osd_req_finalize_data_integrity(struct osd_request *or,
 		or->out.last_seg = NULL;
 
 		/* they are now all chained to request sign them all together */
-		osd_sec_sign_data(&or->out_data_integ, or->out.req->bio,
+		osd_sec_sign_data(&or->out_data_integ, out_data_bio,
 				  cap_key);
 	}
 

@@ -1408,6 +1538,8 @@ int osd_finalize_request(struct osd_request *or,
 {
 	struct osd_cdb_head *cdbh = osd_cdb_head(&or->cdb);
 	bool has_in, has_out;
+	 /* Save for data_integrity without the cdb_continuation */
+	struct bio *out_data_bio = or->out.bio;
 	u64 out_data_bytes = or->out.total_bytes;
 	int ret;
 

@@ -1423,9 +1555,14 @@ int osd_finalize_request(struct osd_request *or,
 	osd_set_caps(&or->cdb, cap);
 
 	has_in = or->in.bio || or->get_attr.total_bytes;
-	has_out = or->out.bio || or->set_attr.total_bytes ||
-		or->enc_get_attr.total_bytes;
+	has_out = or->out.bio || or->cdb_cont.total_bytes ||
+		or->set_attr.total_bytes || or->enc_get_attr.total_bytes;
 
+	ret = _osd_req_finalize_cdb_cont(or, cap_key);
+	if (ret) {
+		OSD_DEBUG("_osd_req_finalize_cdb_cont failed\n");
+		return ret;
+	}
 	ret = _init_blk_request(or, has_in, has_out);
 	if (ret) {
 		OSD_DEBUG("_init_blk_request failed\n");

@@ -1463,7 +1600,8 @@ int osd_finalize_request(struct osd_request *or,
 	}
 
 	ret = _osd_req_finalize_data_integrity(or, has_in, has_out,
-					       out_data_bytes, cap_key);
+					       out_data_bio, out_data_bytes,
+					       cap_key);
 	if (ret)
 		return ret;
 

index a8f3701..169a5dc 100644
@@ -137,7 +137,7 @@ struct osd_request {
 		void *buff;
 		unsigned alloc_size; /* 0 here means: don't call kfree */
 		unsigned total_bytes;
-	} set_attr, enc_get_attr, get_attr;
+	} cdb_cont, set_attr, enc_get_attr, get_attr;
 
 	struct _osd_io_info {
 		struct bio *bio;

@@ -448,6 +448,13 @@ void osd_req_read(struct osd_request *or,
 int osd_req_read_kern(struct osd_request *or,
 	const struct osd_obj_id *obj, u64 offset, void *buff, u64 len);
 
+/* Scatter/Gather write/read commands */
+int osd_req_write_sg(struct osd_request *or,
+	const struct osd_obj_id *obj, struct bio *bio,
+	const struct osd_sg_entry *sglist, unsigned numentries);
+int osd_req_read_sg(struct osd_request *or,
+	const struct osd_obj_id *obj, struct bio *bio,
+	const struct osd_sg_entry *sglist, unsigned numentries);
 /*
  * Root/Partition/Collection/Object Attributes commands
  */

46 lines not on this page · raw message

index 3f5e88c..bd0be7e 100644
@@ -37,4 +37,9 @@ struct osd_attr {
 	void *val_ptr;		/* in network order */
 };
 
+struct osd_sg_entry {
+	u64 offset;
+	u64 len;
+};
+
 #endif /* ndef __OSD_TYPES_H__ */

index f5b5735..0433ea6 100644
@@ -1015,6 +1015,77 @@ int osd_req_read_sg(struct osd_request *or,
 }
 EXPORT_SYMBOL(osd_req_read_sg);
 
+/* SG-list write/read Kern API
+ *
+ * osd_req_{write,read}_sg_kern takes an array of @buff pointers and an array
+ * of sg_entries. @numentries indicates how many pointers and sg_entries there
+ * are.  By requiring an array of buff pointers. This allows a caller to do a
+ * single write/read and scatter into multiple buffers.
+ * NOTE: Each buffer + len should not cross a page boundary.
+ */
+static struct bio *_create_sg_bios(struct osd_request *or,
+	void **buff, const struct osd_sg_entry *sglist, unsigned numentries)
+{
+	struct request_queue *q = osd_request_queue(or->osd_dev);
+	struct bio *bio;
+	unsigned i;
+
+	bio = bio_kmalloc(GFP_KERNEL, numentries);
+	if (unlikely(!bio)) {
+		OSD_DEBUG("Faild to allocate BIO size=%u\n", numentries);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	for (i = 0; i < numentries; i++) {
+		unsigned offset = offset_in_page(buff[i]);
+		struct page *page = virt_to_page(buff[i]);
+		unsigned len = sglist[i].len;
+		unsigned added_len;
+
+		BUG_ON(offset + len > PAGE_SIZE);
+		added_len = bio_add_pc_page(q, bio, page, len, offset);
+		if (unlikely(len != added_len)) {
+			OSD_DEBUG("bio_add_pc_page len(%d) != added_len(%d)\n",
+				  len, added_len);
+			bio_put(bio);
+			return ERR_PTR(-ENOMEM);
+		}
+	}
+
+	return bio;
+}
+
+int osd_req_write_sg_kern(struct osd_request *or,
+	const struct osd_obj_id *obj, void **buff,
+	const struct osd_sg_entry *sglist, unsigned numentries)
+{
+	struct bio *bio = _create_sg_bios(or, buff, sglist, numentries);
+	if (IS_ERR(bio))
+		return PTR_ERR(bio);
+
+	bio->bi_rw |= REQ_WRITE;
+	osd_req_write_sg(or, obj, bio, sglist, numentries);
+
+	return 0;
+}
+EXPORT_SYMBOL(osd_req_write_sg_kern);
+
+int osd_req_read_sg_kern(struct osd_request *or,
+	const struct osd_obj_id *obj, void **buff,
+	const struct osd_sg_entry *sglist, unsigned numentries)
+{
+	struct bio *bio = _create_sg_bios(or, buff, sglist, numentries);
+	if (IS_ERR(bio))
+		return PTR_ERR(bio);
+
+	osd_req_read_sg(or, obj, bio, sglist, numentries);
+
+	return 0;
+}
+EXPORT_SYMBOL(osd_req_read_sg_kern);
+
+
+
 void osd_req_get_attributes(struct osd_request *or,
 	const struct osd_obj_id *obj)
 {

index f5b5735..0433ea6 100644
@@ -1015,6 +1015,77 @@ int osd_req_read_sg(struct osd_request *or,
 }
 EXPORT_SYMBOL(osd_req_read_sg);
 
+/* SG-list write/read Kern API
+ *
+ * osd_req_{write,read}_sg_kern takes an array of @buff pointers and an array
+ * of sg_entries. @numentries indicates how many pointers and sg_entries there
+ * are.  By requiring an array of buff pointers. This allows a caller to do a
+ * single write/read and scatter into multiple buffers.
+ * NOTE: Each buffer + len should not cross a page boundary.
+ */
+static struct bio *_create_sg_bios(struct osd_request *or,
+	void **buff, const struct osd_sg_entry *sglist, unsigned numentries)
+{
+	struct request_queue *q = osd_request_queue(or->osd_dev);
+	struct bio *bio;
+	unsigned i;
+
+	bio = bio_kmalloc(GFP_KERNEL, numentries);
+	if (unlikely(!bio)) {
+		OSD_DEBUG("Faild to allocate BIO size=%u\n", numentries);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	for (i = 0; i < numentries; i++) {
+		unsigned offset = offset_in_page(buff[i]);
+		struct page *page = virt_to_page(buff[i]);
+		unsigned len = sglist[i].len;
+		unsigned added_len;
+
+		BUG_ON(offset + len > PAGE_SIZE);
+		added_len = bio_add_pc_page(q, bio, page, len, offset);
+		if (unlikely(len != added_len)) {
+			OSD_DEBUG("bio_add_pc_page len(%d) != added_len(%d)\n",
+				  len, added_len);
+			bio_put(bio);
+			return ERR_PTR(-ENOMEM);
+		}
+	}
+
+	return bio;
+}
+
+int osd_req_write_sg_kern(struct osd_request *or,
+	const struct osd_obj_id *obj, void **buff,
+	const struct osd_sg_entry *sglist, unsigned numentries)
+{
+	struct bio *bio = _create_sg_bios(or, buff, sglist, numentries);
+	if (IS_ERR(bio))
+		return PTR_ERR(bio);
+
+	bio->bi_rw |= REQ_WRITE;
+	osd_req_write_sg(or, obj, bio, sglist, numentries);
+
+	return 0;
+}
+EXPORT_SYMBOL(osd_req_write_sg_kern);
+
+int osd_req_read_sg_kern(struct osd_request *or,
+	const struct osd_obj_id *obj, void **buff,
+	const struct osd_sg_entry *sglist, unsigned numentries)
+{
+	struct bio *bio = _create_sg_bios(or, buff, sglist, numentries);
+	if (IS_ERR(bio))
+		return PTR_ERR(bio);
+
+	osd_req_read_sg(or, obj, bio, sglist, numentries);
+
+	return 0;
+}
+EXPORT_SYMBOL(osd_req_read_sg_kern);
+
+
+
 void osd_req_get_attributes(struct osd_request *or,
 	const struct osd_obj_id *obj)
 {

index 169a5dc..53a9e88 100644
@@ -455,6 +455,13 @@ int osd_req_write_sg(struct osd_request *or,
 int osd_req_read_sg(struct osd_request *or,
 	const struct osd_obj_id *obj, struct bio *bio,
 	const struct osd_sg_entry *sglist, unsigned numentries);
+int osd_req_write_sg_kern(struct osd_request *or,
+	const struct osd_obj_id *obj, void **buff,
+	const struct osd_sg_entry *sglist, unsigned numentries);
+int osd_req_read_sg_kern(struct osd_request *or,
+	const struct osd_obj_id *obj, void **buff,
+	const struct osd_sg_entry *sglist, unsigned numentries);
+
 /*
  * Root/Partition/Collection/Object Attributes commands
  */