2 * SCSI RDAM Protocol lib functions
4 * Copyright (C) 2006 FUJITA Tomonori <tomof@acm.org>
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation; either version 2 of the
9 * License, or (at your option) any later version.
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
21 #include <linux/err.h>
22 #include <linux/kfifo.h>
23 #include <linux/scatterlist.h>
24 #include <linux/dma-mapping.h>
25 #include <scsi/scsi.h>
26 #include <scsi/scsi_cmnd.h>
27 #include <scsi/scsi_tcq.h>
28 #include <scsi/scsi_tgt.h>
30 #include <scsi/libsrp.h>
32 enum srp_task_attributes {
39 /* tmp - will replace with SCSI logging stuff */
40 #define eprintk(fmt, args...) \
42 printk("%s(%d) " fmt, __func__, __LINE__, ##args); \
44 /* #define dprintk eprintk */
45 #define dprintk(fmt, args...)
47 static int srp_iu_pool_alloc(struct srp_queue *q, size_t max,
48 struct srp_buf **ring)
53 q->pool = kcalloc(max, sizeof(struct iu_entry *), GFP_KERNEL);
56 q->items = kcalloc(max, sizeof(struct iu_entry), GFP_KERNEL);
60 spin_lock_init(&q->lock);
61 kfifo_init(&q->queue, (void *) q->pool, max * sizeof(void *));
63 for (i = 0, iue = q->items; i < max; i++) {
64 kfifo_put(&q->queue, (void *) &iue, sizeof(void *));
76 static void srp_iu_pool_free(struct srp_queue *q)
82 static struct srp_buf **srp_ring_alloc(struct device *dev,
83 size_t max, size_t size)
86 struct srp_buf **ring;
88 ring = kcalloc(max, sizeof(struct srp_buf *), GFP_KERNEL);
92 for (i = 0; i < max; i++) {
93 ring[i] = kzalloc(sizeof(struct srp_buf), GFP_KERNEL);
96 ring[i]->buf = dma_alloc_coherent(dev, size, &ring[i]->dma,
104 for (i = 0; i < max && ring[i]; i++) {
106 dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma);
114 static void srp_ring_free(struct device *dev, struct srp_buf **ring, size_t max,
119 for (i = 0; i < max; i++) {
120 dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma);
126 int srp_target_alloc(struct srp_target *target, struct device *dev,
127 size_t nr, size_t iu_size)
131 spin_lock_init(&target->lock);
132 INIT_LIST_HEAD(&target->cmd_queue);
135 dev_set_drvdata(target->dev, target);
137 target->srp_iu_size = iu_size;
138 target->rx_ring_size = nr;
139 target->rx_ring = srp_ring_alloc(target->dev, nr, iu_size);
140 if (!target->rx_ring)
142 err = srp_iu_pool_alloc(&target->iu_queue, nr, target->rx_ring);
149 srp_ring_free(target->dev, target->rx_ring, nr, iu_size);
152 EXPORT_SYMBOL_GPL(srp_target_alloc);
154 void srp_target_free(struct srp_target *target)
156 srp_ring_free(target->dev, target->rx_ring, target->rx_ring_size,
157 target->srp_iu_size);
158 srp_iu_pool_free(&target->iu_queue);
160 EXPORT_SYMBOL_GPL(srp_target_free);
162 struct iu_entry *srp_iu_get(struct srp_target *target)
164 struct iu_entry *iue = NULL;
166 kfifo_get_locked(&target->iu_queue.queue, (void *) &iue,
167 sizeof(void *), &target->iu_queue.lock);
170 iue->target = target;
171 INIT_LIST_HEAD(&iue->ilist);
175 EXPORT_SYMBOL_GPL(srp_iu_get);
177 void srp_iu_put(struct iu_entry *iue)
179 kfifo_put_locked(&iue->target->iu_queue.queue, (void *) &iue,
180 sizeof(void *), &iue->target->iu_queue.lock);
182 EXPORT_SYMBOL_GPL(srp_iu_put);
184 static int srp_direct_data(struct scsi_cmnd *sc, struct srp_direct_buf *md,
185 enum dma_data_direction dir, srp_rdma_t rdma_io,
186 int dma_map, int ext_desc)
188 struct iu_entry *iue = NULL;
189 struct scatterlist *sg = NULL;
190 int err, nsg = 0, len;
193 iue = (struct iu_entry *) sc->SCp.ptr;
194 sg = scsi_sglist(sc);
196 dprintk("%p %u %u %d\n", iue, scsi_bufflen(sc),
197 md->len, scsi_sg_count(sc));
199 nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc),
202 printk("fail to map %p %d\n", iue, scsi_sg_count(sc));
205 len = min(scsi_bufflen(sc), md->len);
209 err = rdma_io(sc, sg, nsg, md, 1, dir, len);
212 dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
217 static int srp_indirect_data(struct scsi_cmnd *sc, struct srp_cmd *cmd,
218 struct srp_indirect_buf *id,
219 enum dma_data_direction dir, srp_rdma_t rdma_io,
220 int dma_map, int ext_desc)
222 struct iu_entry *iue = NULL;
223 struct srp_direct_buf *md = NULL;
224 struct scatterlist dummy, *sg = NULL;
225 dma_addr_t token = 0;
227 int nmd, nsg = 0, len;
229 if (dma_map || ext_desc) {
230 iue = (struct iu_entry *) sc->SCp.ptr;
231 sg = scsi_sglist(sc);
233 dprintk("%p %u %u %d %d\n",
234 iue, scsi_bufflen(sc), id->len,
235 cmd->data_in_desc_cnt, cmd->data_out_desc_cnt);
238 nmd = id->table_desc.len / sizeof(struct srp_direct_buf);
240 if ((dir == DMA_FROM_DEVICE && nmd == cmd->data_in_desc_cnt) ||
241 (dir == DMA_TO_DEVICE && nmd == cmd->data_out_desc_cnt)) {
242 md = &id->desc_list[0];
246 if (ext_desc && dma_map) {
247 md = dma_alloc_coherent(iue->target->dev, id->table_desc.len,
250 eprintk("Can't get dma memory %u\n", id->table_desc.len);
254 sg_init_one(&dummy, md, id->table_desc.len);
255 sg_dma_address(&dummy) = token;
256 sg_dma_len(&dummy) = id->table_desc.len;
257 err = rdma_io(sc, &dummy, 1, &id->table_desc, 1, DMA_TO_DEVICE,
260 eprintk("Error copying indirect table %d\n", err);
264 eprintk("This command uses external indirect buffer\n");
270 nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc),
273 eprintk("fail to map %p %d\n", iue, scsi_sg_count(sc));
277 len = min(scsi_bufflen(sc), id->len);
281 err = rdma_io(sc, sg, nsg, md, nmd, dir, len);
284 dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
287 if (token && dma_map)
288 dma_free_coherent(iue->target->dev, id->table_desc.len, md, token);
293 static int data_out_desc_size(struct srp_cmd *cmd)
296 u8 fmt = cmd->buf_fmt >> 4;
299 case SRP_NO_DATA_DESC:
301 case SRP_DATA_DESC_DIRECT:
302 size = sizeof(struct srp_direct_buf);
304 case SRP_DATA_DESC_INDIRECT:
305 size = sizeof(struct srp_indirect_buf) +
306 sizeof(struct srp_direct_buf) * cmd->data_out_desc_cnt;
309 eprintk("client error. Invalid data_out_format %x\n", fmt);
316 * TODO: this can be called multiple times for a single command if it
317 * has very long data.
319 int srp_transfer_data(struct scsi_cmnd *sc, struct srp_cmd *cmd,
320 srp_rdma_t rdma_io, int dma_map, int ext_desc)
322 struct srp_direct_buf *md;
323 struct srp_indirect_buf *id;
324 enum dma_data_direction dir;
328 offset = cmd->add_cdb_len * 4;
330 dir = srp_cmd_direction(cmd);
331 if (dir == DMA_FROM_DEVICE)
332 offset += data_out_desc_size(cmd);
334 if (dir == DMA_TO_DEVICE)
335 format = cmd->buf_fmt >> 4;
337 format = cmd->buf_fmt & ((1U << 4) - 1);
340 case SRP_NO_DATA_DESC:
342 case SRP_DATA_DESC_DIRECT:
343 md = (struct srp_direct_buf *)
344 (cmd->add_data + offset);
345 err = srp_direct_data(sc, md, dir, rdma_io, dma_map, ext_desc);
347 case SRP_DATA_DESC_INDIRECT:
348 id = (struct srp_indirect_buf *)
349 (cmd->add_data + offset);
350 err = srp_indirect_data(sc, cmd, id, dir, rdma_io, dma_map,
354 eprintk("Unknown format %d %x\n", dir, format);
360 EXPORT_SYMBOL_GPL(srp_transfer_data);
362 static int vscsis_data_length(struct srp_cmd *cmd, enum dma_data_direction dir)
364 struct srp_direct_buf *md;
365 struct srp_indirect_buf *id;
366 int len = 0, offset = cmd->add_cdb_len * 4;
369 if (dir == DMA_TO_DEVICE)
370 fmt = cmd->buf_fmt >> 4;
372 fmt = cmd->buf_fmt & ((1U << 4) - 1);
373 offset += data_out_desc_size(cmd);
377 case SRP_NO_DATA_DESC:
379 case SRP_DATA_DESC_DIRECT:
380 md = (struct srp_direct_buf *) (cmd->add_data + offset);
383 case SRP_DATA_DESC_INDIRECT:
384 id = (struct srp_indirect_buf *) (cmd->add_data + offset);
388 eprintk("invalid data format %x\n", fmt);
394 int srp_cmd_queue(struct Scsi_Host *shost, struct srp_cmd *cmd, void *info,
395 u64 itn_id, u64 addr)
397 enum dma_data_direction dir;
398 struct scsi_cmnd *sc;
401 switch (cmd->task_attr) {
402 case SRP_SIMPLE_TASK:
403 tag = MSG_SIMPLE_TAG;
405 case SRP_ORDERED_TASK:
406 tag = MSG_ORDERED_TAG;
412 eprintk("Task attribute %d not supported\n", cmd->task_attr);
413 tag = MSG_ORDERED_TAG;
416 dir = srp_cmd_direction(cmd);
417 len = vscsis_data_length(cmd, dir);
419 dprintk("%p %x %lx %d %d %d %llx\n", info, cmd->cdb[0],
420 cmd->lun, dir, len, tag, (unsigned long long) cmd->tag);
422 sc = scsi_host_get_command(shost, dir, GFP_KERNEL);
427 memcpy(sc->cmnd, cmd->cdb, MAX_COMMAND_SIZE);
428 sc->sdb.length = len;
429 sc->sdb.table.sgl = (void *) (unsigned long) addr;
431 err = scsi_tgt_queue_command(sc, itn_id, (struct scsi_lun *)&cmd->lun,
434 scsi_host_put_command(shost, sc);
438 EXPORT_SYMBOL_GPL(srp_cmd_queue);
440 MODULE_DESCRIPTION("SCSI RDAM Protocol lib functions");
441 MODULE_AUTHOR("FUJITA Tomonori");
442 MODULE_LICENSE("GPL");