/* * SCSI RDAM Protocol lib functions * * Copyright (C) 2006 FUJITA Tomonori <tomof@acm.org> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of the * License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA */ #include <linux/err.h> #include <linux/kfifo.h> #include <linux/scatterlist.h> #include <linux/dma-mapping.h> #include <scsi/scsi.h> #include <scsi/scsi_cmnd.h> #include <scsi/scsi_tcq.h> #include <scsi/scsi_tgt.h> #include <scsi/srp.h> #include <scsi/libsrp.h> enum srp_task_attributes { SRP_SIMPLE_TASK = 0, SRP_HEAD_TASK = 1, SRP_ORDERED_TASK = 2, SRP_ACA_TASK = 4 }; /* tmp - will replace with SCSI logging stuff */ #define eprintk(fmt, args...) \ do { \ printk("%s(%d) " fmt, __FUNCTION__, __LINE__, ##args); \ } while (0) /* #define dprintk eprintk */ #define dprintk(fmt, args...) static int srp_iu_pool_alloc(struct srp_queue *q, size_t max, struct srp_buf **ring) { int i; struct iu_entry *iue; q->pool = kcalloc(max, sizeof(struct iu_entry *), GFP_KERNEL); if (!q->pool) return -ENOMEM; q->items = kcalloc(max, sizeof(struct iu_entry), GFP_KERNEL); if (!q->items) goto free_pool; spin_lock_init(&q->lock); q->queue = kfifo_init((void *) q->pool, max * sizeof(void *), GFP_KERNEL, &q->lock); if (IS_ERR(q->queue)) goto free_item; for (i = 0, iue = q->items; i < max; i++) { __kfifo_put(q->queue, (void *) &iue, sizeof(void *)); iue->sbuf = ring[i]; iue++; } return 0; free_item: kfree(q->items); free_pool: kfree(q->pool); return -ENOMEM; } static void srp_iu_pool_free(struct srp_queue *q) { kfree(q->items); kfree(q->pool); } static struct srp_buf **srp_ring_alloc(struct device *dev, size_t max, size_t size) { int i; struct srp_buf **ring; ring = kcalloc(max, sizeof(struct srp_buf *), GFP_KERNEL); if (!ring) return NULL; for (i = 0; i < max; i++) { ring[i] = kzalloc(sizeof(struct srp_buf), GFP_KERNEL); if (!ring[i]) goto out; ring[i]->buf = dma_alloc_coherent(dev, size, &ring[i]->dma, GFP_KERNEL); if (!ring[i]->buf) goto out; } return ring; out: for (i = 0; i < max && ring[i]; i++) { if (ring[i]->buf) dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma); kfree(ring[i]); } kfree(ring); return NULL; } static void srp_ring_free(struct device *dev, struct srp_buf **ring, size_t max, size_t size) { int i; for (i = 0; i < max; i++) { dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma); kfree(ring[i]); } } int srp_target_alloc(struct srp_target *target, struct device *dev, size_t nr, size_t iu_size) { int err; spin_lock_init(&target->lock); INIT_LIST_HEAD(&target->cmd_queue); target->dev = dev; target->dev->driver_data = target; target->srp_iu_size = iu_size; target->rx_ring_size = nr; target->rx_ring = srp_ring_alloc(target->dev, nr, iu_size); if (!target->rx_ring) return -ENOMEM; err = srp_iu_pool_alloc(&target->iu_queue, nr, target->rx_ring); if (err) goto free_ring; return 0; free_ring: srp_ring_free(target->dev, target->rx_ring, nr, iu_size); return -ENOMEM; } EXPORT_SYMBOL_GPL(srp_target_alloc); void srp_target_free(struct srp_target *target) { srp_ring_free(target->dev, target->rx_ring, target->rx_ring_size, target->srp_iu_size); srp_iu_pool_free(&target->iu_queue); } EXPORT_SYMBOL_GPL(srp_target_free); struct iu_entry *srp_iu_get(struct srp_target *target) { struct iu_entry *iue = NULL; kfifo_get(target->iu_queue.queue, (void *) &iue, sizeof(void *)); if (!iue) return iue; iue->target = target; INIT_LIST_HEAD(&iue->ilist); iue->flags = 0; return iue; } EXPORT_SYMBOL_GPL(srp_iu_get); void srp_iu_put(struct iu_entry *iue) { kfifo_put(iue->target->iu_queue.queue, (void *) &iue, sizeof(void *)); } EXPORT_SYMBOL_GPL(srp_iu_put); static int srp_direct_data(struct scsi_cmnd *sc, struct srp_direct_buf *md, enum dma_data_direction dir, srp_rdma_t rdma_io, int dma_map, int ext_desc) { struct iu_entry *iue = NULL; struct scatterlist *sg = NULL; int err, nsg = 0, len; if (dma_map) { iue = (struct iu_entry *) sc->SCp.ptr; sg = scsi_sglist(sc); dprintk("%p %u %u %d\n", iue, scsi_bufflen(sc), md->len, scsi_sg_count(sc)); nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc), DMA_BIDIRECTIONAL); if (!nsg) { printk("fail to map %p %d\n", iue, scsi_sg_count(sc)); return 0; } len = min(scsi_bufflen(sc), md->len); } else len = md->len; err = rdma_io(sc, sg, nsg, md, 1, dir, len); if (dma_map) dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL); return err; } static int srp_indirect_data(struct scsi_cmnd *sc, struct srp_cmd *cmd, struct srp_indirect_buf *id, enum dma_data_direction dir, srp_rdma_t rdma_io, int dma_map, int ext_desc) { struct iu_entry *iue = NULL; struct srp_direct_buf *md = NULL; struct scatterlist dummy, *sg = NULL; dma_addr_t token = 0; int err = 0; int nmd, nsg = 0, len; if (dma_map || ext_desc) { iue = (struct iu_entry *) sc->SCp.ptr; sg = scsi_sglist(sc); dprintk("%p %u %u %d %d\n", iue, scsi_bufflen(sc), id->len, cmd->data_in_desc_cnt, cmd->data_out_desc_cnt); } nmd = id->table_desc.len / sizeof(struct srp_direct_buf); if ((dir == DMA_FROM_DEVICE && nmd == cmd->data_in_desc_cnt) || (dir == DMA_TO_DEVICE && nmd == cmd->data_out_desc_cnt)) { md = &id->desc_list[0]; goto rdma; } if (ext_desc && dma_map) { md = dma_alloc_coherent(iue->target->dev, id->table_desc.len, &token, GFP_KERNEL); if (!md) { eprintk("Can't get dma memory %u\n", id->table_desc.len); return -ENOMEM; } sg_init_one(&dummy, md, id->table_desc.len); sg_dma_address(&dummy) = token; sg_dma_len(&dummy) = id->table_desc.len; err = rdma_io(sc, &dummy, 1, &id->table_desc, 1, DMA_TO_DEVICE, id->table_desc.len); if (err) { eprintk("Error copying indirect table %d\n", err); goto free_mem; } } else { eprintk("This command uses external indirect buffer\n"); return -EINVAL; } rdma: if (dma_map) { nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc), DMA_BIDIRECTIONAL); if (!nsg) { eprintk("fail to map %p %d\n", iue, scsi_sg_count(sc)); err = -EIO; goto free_mem; } len = min(scsi_bufflen(sc), id->len); } else len = id->len; err = rdma_io(sc, sg, nsg, md, nmd, dir, len); if (dma_map) dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL); free_mem: if (token && dma_map) dma_free_coherent(iue->target->dev, id->table_desc.len, md, token); return err; } static int data_out_desc_size(struct srp_cmd *cmd) { int size = 0; u8 fmt = cmd->buf_fmt >> 4; switch (fmt) { case SRP_NO_DATA_DESC: break; case SRP_DATA_DESC_DIRECT: size = sizeof(struct srp_direct_buf); break; case SRP_DATA_DESC_INDIRECT: size = sizeof(struct srp_indirect_buf) + sizeof(struct srp_direct_buf) * cmd->data_out_desc_cnt; break; default: eprintk("client error. Invalid data_out_format %x\n", fmt); break; } return size; } /* * TODO: this can be called multiple times for a single command if it * has very long data. */ int srp_transfer_data(struct scsi_cmnd *sc, struct srp_cmd *cmd, srp_rdma_t rdma_io, int dma_map, int ext_desc) { struct srp_direct_buf *md; struct srp_indirect_buf *id; enum dma_data_direction dir; int offset, err = 0; u8 format; offset = cmd->add_cdb_len * 4; dir = srp_cmd_direction(cmd); if (dir == DMA_FROM_DEVICE) offset += data_out_desc_size(cmd); if (dir == DMA_TO_DEVICE) format = cmd->buf_fmt >> 4; else format = cmd->buf_fmt & ((1U << 4) - 1); switch (format) { case SRP_NO_DATA_DESC: break; case SRP_DATA_DESC_DIRECT: md = (struct srp_direct_buf *) (cmd->add_data + offset); err = srp_direct_data(sc, md, dir, rdma_io, dma_map, ext_desc); break; case SRP_DATA_DESC_INDIRECT: id = (struct srp_indirect_buf *) (cmd->add_data + offset); err = srp_indirect_data(sc, cmd, id, dir, rdma_io, dma_map, ext_desc); break; default: eprintk("Unknown format %d %x\n", dir, format); err = -EINVAL; } return err; } EXPORT_SYMBOL_GPL(srp_transfer_data); static int vscsis_data_length(struct srp_cmd *cmd, enum dma_data_direction dir) { struct srp_direct_buf *md; struct srp_indirect_buf *id; int len = 0, offset = cmd->add_cdb_len * 4; u8 fmt; if (dir == DMA_TO_DEVICE) fmt = cmd->buf_fmt >> 4; else { fmt = cmd->buf_fmt & ((1U << 4) - 1); offset += data_out_desc_size(cmd); } switch (fmt) { case SRP_NO_DATA_DESC: break; case SRP_DATA_DESC_DIRECT: md = (struct srp_direct_buf *) (cmd->add_data + offset); len = md->len; break; case SRP_DATA_DESC_INDIRECT: id = (struct srp_indirect_buf *) (cmd->add_data + offset); len = id->len; break; default: eprintk("invalid data format %x\n", fmt); break; } return len; } int srp_cmd_queue(struct Scsi_Host *shost, struct srp_cmd *cmd, void *info, u64 itn_id, u64 addr) { enum dma_data_direction dir; struct scsi_cmnd *sc; int tag, len, err; switch (cmd->task_attr) { case SRP_SIMPLE_TASK: tag = MSG_SIMPLE_TAG; break; case SRP_ORDERED_TASK: tag = MSG_ORDERED_TAG; break; case SRP_HEAD_TASK: tag = MSG_HEAD_TAG; break; default: eprintk("Task attribute %d not supported\n", cmd->task_attr); tag = MSG_ORDERED_TAG; } dir = srp_cmd_direction(cmd); len = vscsis_data_length(cmd, dir); dprintk("%p %x %lx %d %d %d %llx\n", info, cmd->cdb[0], cmd->lun, dir, len, tag, (unsigned long long) cmd->tag); sc = scsi_host_get_command(shost, dir, GFP_KERNEL); if (!sc) return -ENOMEM; sc->SCp.ptr = info; memcpy(sc->cmnd, cmd->cdb, MAX_COMMAND_SIZE); sc->sdb.length = len; sc->sdb.table.sgl = (void *) (unsigned long) addr; sc->tag = tag; err = scsi_tgt_queue_command(sc, itn_id, (struct scsi_lun *)&cmd->lun, cmd->tag); if (err) scsi_host_put_command(shost, sc); return err; } EXPORT_SYMBOL_GPL(srp_cmd_queue); MODULE_DESCRIPTION("SCSI RDAM Protocol lib functions"); MODULE_AUTHOR("FUJITA Tomonori"); MODULE_LICENSE("GPL");