diff options
Diffstat (limited to 'drivers/scsi')
| -rw-r--r-- | drivers/scsi/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/scsi/Makefile | 1 | ||||
| -rw-r--r-- | drivers/scsi/libsrp.c | 441 |
3 files changed, 452 insertions, 0 deletions
diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig index 1301d5222c0..5570cdbf8f1 100644 --- a/drivers/scsi/Kconfig +++ b/drivers/scsi/Kconfig @@ -1760,6 +1760,16 @@ config ZFCP called zfcp. If you want to compile it as a module, say M here and read <file:Documentation/modules.txt>. +config SCSI_SRP + tristate "SCSI RDMA Protocol helper library" + depends on SCSI && PCI + select SCSI_TGT + help + If you wish to use SRP target drivers, say Y. + + To compile this driver as a module, choose M here: the + module will be called libsrp. + endmenu source "drivers/scsi/pcmcia/Kconfig" diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile index 8f86c1b96ff..00691c4c3a6 100644 --- a/drivers/scsi/Makefile +++ b/drivers/scsi/Makefile @@ -126,6 +126,7 @@ obj-$(CONFIG_SCSI_FCAL) += fcal.o obj-$(CONFIG_SCSI_LASI700) += 53c700.o lasi700.o obj-$(CONFIG_SCSI_NSP32) += nsp32.o obj-$(CONFIG_SCSI_IPR) += ipr.o +obj-$(CONFIG_SCSI_SRP) += libsrp.o obj-$(CONFIG_SCSI_IBMVSCSI) += ibmvscsi/ obj-$(CONFIG_SCSI_HPTIOP) += hptiop.o obj-$(CONFIG_SCSI_STEX) += stex.o diff --git a/drivers/scsi/libsrp.c b/drivers/scsi/libsrp.c new file mode 100644 index 00000000000..89403b00e04 --- /dev/null +++ b/drivers/scsi/libsrp.c @@ -0,0 +1,441 @@ +/* + * 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 <linux/pci.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 = sc->request_buffer; + + dprintk("%p %u %u %d\n", iue, sc->request_bufflen, + md->len, sc->use_sg); + + nsg = dma_map_sg(iue->target->dev, sg, sc->use_sg, + DMA_BIDIRECTIONAL); + if (!nsg) { + printk("fail to map %p %d\n", iue, sc->use_sg); + return 0; + } + len = min(sc->request_bufflen, 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; + long err; + unsigned int done = 0; + int nmd, nsg = 0, len; + + if (dma_map || ext_desc) { + iue = (struct iu_entry *) sc->SCp.ptr; + sg = sc->request_buffer; + + dprintk("%p %u %u %d %d\n", + iue, sc->request_bufflen, 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; + err = rdma_io(sc, &dummy, 1, &id->table_desc, 1, DMA_TO_DEVICE, + id->table_desc.len); + if (err < 0) { + eprintk("Error copying indirect table %ld\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, sc->use_sg, DMA_BIDIRECTIONAL); + if (!nsg) { + eprintk("fail to map %p %d\n", iue, sc->use_sg); + goto free_mem; + } + len = min(sc->request_bufflen, 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 done; +} + +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); + break; + } + + 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 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->request_bufflen = len; + sc->request_buffer = (void *) (unsigned long) addr; + sc->tag = tag; + err = scsi_tgt_queue_command(sc, (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"); |