2 * SCSI RDMA 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/slab.h>
23 #include <linux/kfifo.h>
24 #include <linux/scatterlist.h>
25 #include <linux/dma-mapping.h>
26 #include <scsi/scsi.h>
27 #include <scsi/scsi_cmnd.h>
28 #include <scsi/scsi_tcq.h>
29 #include <scsi/scsi_tgt.h>
31 #include <scsi/libsrp.h>
33 enum srp_task_attributes {
40 /* tmp - will replace with SCSI logging stuff */
41 #define eprintk(fmt, args...) \
43 printk("%s(%d) " fmt, __func__, __LINE__, ##args); \
45 /* #define dprintk eprintk */
46 #define dprintk(fmt, args...)
48 static int srp_iu_pool_alloc(struct srp_queue *q, size_t max,
49 struct srp_buf **ring)
54 q->pool = kcalloc(max, sizeof(struct iu_entry *), GFP_KERNEL);
57 q->items = kcalloc(max, sizeof(struct iu_entry), GFP_KERNEL);
61 spin_lock_init(&q->lock);
62 kfifo_init(&q->queue, (void *) q->pool, max * sizeof(void *));
64 for (i = 0, iue = q->items; i < max; i++) {
65 kfifo_in(&q->queue, (void *) &iue, sizeof(void *));
77 static void srp_iu_pool_free(struct srp_queue *q)
83 static struct srp_buf **srp_ring_alloc(struct device *dev,
84 size_t max, size_t size)
87 struct srp_buf **ring;
89 ring = kcalloc(max, sizeof(struct srp_buf *), GFP_KERNEL);
93 for (i = 0; i < max; i++) {
94 ring[i] = kzalloc(sizeof(struct srp_buf), GFP_KERNEL);
97 ring[i]->buf = dma_alloc_coherent(dev, size, &ring[i]->dma,
105 for (i = 0; i < max && ring[i]; i++) {
107 dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma);
115 static void srp_ring_free(struct device *dev, struct srp_buf **ring, size_t max,
120 for (i = 0; i < max; i++) {
121 dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma);
127 int srp_target_alloc(struct srp_target *target, struct device *dev,
128 size_t nr, size_t iu_size)
132 spin_lock_init(&target->lock);
133 INIT_LIST_HEAD(&target->cmd_queue);
136 dev_set_drvdata(target->dev, target);
138 target->srp_iu_size = iu_size;
139 target->rx_ring_size = nr;
140 target->rx_ring = srp_ring_alloc(target->dev, nr, iu_size);
141 if (!target->rx_ring)
143 err = srp_iu_pool_alloc(&target->iu_queue, nr, target->rx_ring);
150 srp_ring_free(target->dev, target->rx_ring, nr, iu_size);
153 EXPORT_SYMBOL_GPL(srp_target_alloc);
155 void srp_target_free(struct srp_target *target)
157 srp_ring_free(target->dev, target->rx_ring, target->rx_ring_size,
158 target->srp_iu_size);
159 srp_iu_pool_free(&target->iu_queue);
161 EXPORT_SYMBOL_GPL(srp_target_free);
163 struct iu_entry *srp_iu_get(struct srp_target *target)
165 struct iu_entry *iue = NULL;
167 if (kfifo_out_locked(&target->iu_queue.queue, (void *) &iue,
168 sizeof(void *), &target->iu_queue.lock) != sizeof(void *)) {
169 WARN_ONCE(1, "unexpected fifo state");
174 iue->target = target;
175 INIT_LIST_HEAD(&iue->ilist);
179 EXPORT_SYMBOL_GPL(srp_iu_get);
181 void srp_iu_put(struct iu_entry *iue)
183 kfifo_in_locked(&iue->target->iu_queue.queue, (void *) &iue,
184 sizeof(void *), &iue->target->iu_queue.lock);
186 EXPORT_SYMBOL_GPL(srp_iu_put);
188 static int srp_direct_data(struct scsi_cmnd *sc, struct srp_direct_buf *md,
189 enum dma_data_direction dir, srp_rdma_t rdma_io,
190 int dma_map, int ext_desc)
192 struct iu_entry *iue = NULL;
193 struct scatterlist *sg = NULL;
194 int err, nsg = 0, len;
197 iue = (struct iu_entry *) sc->SCp.ptr;
198 sg = scsi_sglist(sc);
200 dprintk("%p %u %u %d\n", iue, scsi_bufflen(sc),
201 md->len, scsi_sg_count(sc));
203 nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc),
206 printk("fail to map %p %d\n", iue, scsi_sg_count(sc));
209 len = min(scsi_bufflen(sc), md->len);
213 err = rdma_io(sc, sg, nsg, md, 1, dir, len);
216 dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
221 static int srp_indirect_data(struct scsi_cmnd *sc, struct srp_cmd *cmd,
222 struct srp_indirect_buf *id,
223 enum dma_data_direction dir, srp_rdma_t rdma_io,
224 int dma_map, int ext_desc)
226 struct iu_entry *iue = NULL;
227 struct srp_direct_buf *md = NULL;
228 struct scatterlist dummy, *sg = NULL;
229 dma_addr_t token = 0;
231 int nmd, nsg = 0, len;
233 if (dma_map || ext_desc) {
234 iue = (struct iu_entry *) sc->SCp.ptr;
235 sg = scsi_sglist(sc);
237 dprintk("%p %u %u %d %d\n",
238 iue, scsi_bufflen(sc), id->len,
239 cmd->data_in_desc_cnt, cmd->data_out_desc_cnt);
242 nmd = id->table_desc.len / sizeof(struct srp_direct_buf);
244 if ((dir == DMA_FROM_DEVICE && nmd == cmd->data_in_desc_cnt) ||
245 (dir == DMA_TO_DEVICE && nmd == cmd->data_out_desc_cnt)) {
246 md = &id->desc_list[0];
250 if (ext_desc && dma_map) {
251 md = dma_alloc_coherent(iue->target->dev, id->table_desc.len,
254 eprintk("Can't get dma memory %u\n", id->table_desc.len);
258 sg_init_one(&dummy, md, id->table_desc.len);
259 sg_dma_address(&dummy) = token;
260 sg_dma_len(&dummy) = id->table_desc.len;
261 err = rdma_io(sc, &dummy, 1, &id->table_desc, 1, DMA_TO_DEVICE,
264 eprintk("Error copying indirect table %d\n", err);
268 eprintk("This command uses external indirect buffer\n");
274 nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc),
277 eprintk("fail to map %p %d\n", iue, scsi_sg_count(sc));
281 len = min(scsi_bufflen(sc), id->len);
285 err = rdma_io(sc, sg, nsg, md, nmd, dir, len);
288 dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
291 if (token && dma_map)
292 dma_free_coherent(iue->target->dev, id->table_desc.len, md, token);
297 static int data_out_desc_size(struct srp_cmd *cmd)
300 u8 fmt = cmd->buf_fmt >> 4;
303 case SRP_NO_DATA_DESC:
305 case SRP_DATA_DESC_DIRECT:
306 size = sizeof(struct srp_direct_buf);
308 case SRP_DATA_DESC_INDIRECT:
309 size = sizeof(struct srp_indirect_buf) +
310 sizeof(struct srp_direct_buf) * cmd->data_out_desc_cnt;
313 eprintk("client error. Invalid data_out_format %x\n", fmt);
320 * TODO: this can be called multiple times for a single command if it
321 * has very long data.
323 int srp_transfer_data(struct scsi_cmnd *sc, struct srp_cmd *cmd,
324 srp_rdma_t rdma_io, int dma_map, int ext_desc)
326 struct srp_direct_buf *md;
327 struct srp_indirect_buf *id;
328 enum dma_data_direction dir;
332 offset = cmd->add_cdb_len & ~3;
334 dir = srp_cmd_direction(cmd);
335 if (dir == DMA_FROM_DEVICE)
336 offset += data_out_desc_size(cmd);
338 if (dir == DMA_TO_DEVICE)
339 format = cmd->buf_fmt >> 4;
341 format = cmd->buf_fmt & ((1U << 4) - 1);
344 case SRP_NO_DATA_DESC:
346 case SRP_DATA_DESC_DIRECT:
347 md = (struct srp_direct_buf *)
348 (cmd->add_data + offset);
349 err = srp_direct_data(sc, md, dir, rdma_io, dma_map, ext_desc);
351 case SRP_DATA_DESC_INDIRECT:
352 id = (struct srp_indirect_buf *)
353 (cmd->add_data + offset);
354 err = srp_indirect_data(sc, cmd, id, dir, rdma_io, dma_map,
358 eprintk("Unknown format %d %x\n", dir, format);
364 EXPORT_SYMBOL_GPL(srp_transfer_data);
366 static int vscsis_data_length(struct srp_cmd *cmd, enum dma_data_direction dir)
368 struct srp_direct_buf *md;
369 struct srp_indirect_buf *id;
370 int len = 0, offset = cmd->add_cdb_len & ~3;
373 if (dir == DMA_TO_DEVICE)
374 fmt = cmd->buf_fmt >> 4;
376 fmt = cmd->buf_fmt & ((1U << 4) - 1);
377 offset += data_out_desc_size(cmd);
381 case SRP_NO_DATA_DESC:
383 case SRP_DATA_DESC_DIRECT:
384 md = (struct srp_direct_buf *) (cmd->add_data + offset);
387 case SRP_DATA_DESC_INDIRECT:
388 id = (struct srp_indirect_buf *) (cmd->add_data + offset);
392 eprintk("invalid data format %x\n", fmt);
398 int srp_cmd_queue(struct Scsi_Host *shost, struct srp_cmd *cmd, void *info,
399 u64 itn_id, u64 addr)
401 enum dma_data_direction dir;
402 struct scsi_cmnd *sc;
405 switch (cmd->task_attr) {
406 case SRP_SIMPLE_TASK:
407 tag = MSG_SIMPLE_TAG;
409 case SRP_ORDERED_TASK:
410 tag = MSG_ORDERED_TAG;
416 eprintk("Task attribute %d not supported\n", cmd->task_attr);
417 tag = MSG_ORDERED_TAG;
420 dir = srp_cmd_direction(cmd);
421 len = vscsis_data_length(cmd, dir);
423 dprintk("%p %x %lx %d %d %d %llx\n", info, cmd->cdb[0],
424 cmd->lun, dir, len, tag, (unsigned long long) cmd->tag);
426 sc = scsi_host_get_command(shost, dir, GFP_KERNEL);
431 memcpy(sc->cmnd, cmd->cdb, MAX_COMMAND_SIZE);
432 sc->sdb.length = len;
433 sc->sdb.table.sgl = (void *) (unsigned long) addr;
435 err = scsi_tgt_queue_command(sc, itn_id, (struct scsi_lun *)&cmd->lun,
438 scsi_host_put_command(shost, sc);
442 EXPORT_SYMBOL_GPL(srp_cmd_queue);
444 MODULE_DESCRIPTION("SCSI RDMA Protocol lib functions");
445 MODULE_AUTHOR("FUJITA Tomonori");
446 MODULE_LICENSE("GPL");