Miscellaneous functions for dealing with SCSI commands, status, sense
data and data read/write. This is where the real grunt work of pushing
data in and out of the FireWire bus happens.
Signed-off-by: Chris Boot <bootc@xxxxxxxxx>
Cc: Andy Grover <agrover@xxxxxxxxxx>
Cc: Clemens Ladisch <clemens@xxxxxxxxxx>
Cc: Nicholas A. Bellinger <nab@xxxxxxxxxxxxxxx>
Cc: Stefan Richter <stefanr@xxxxxxxxxxxxxxxxx>
---
drivers/target/sbp/sbp_scsi_cmnd.c | 430 ++++++++++++++++++++++++++++++++++++
drivers/target/sbp/sbp_scsi_cmnd.h | 12 +
2 files changed, 442 insertions(+)
create mode 100644 drivers/target/sbp/sbp_scsi_cmnd.c
create mode 100644 drivers/target/sbp/sbp_scsi_cmnd.h
diff --git a/drivers/target/sbp/sbp_scsi_cmnd.c b/drivers/target/sbp/sbp_scsi_cmnd.c
new file mode 100644
index 0000000..13407cf
--- /dev/null
+++ b/drivers/target/sbp/sbp_scsi_cmnd.c
@@ -0,0 +1,430 @@
+/*
+ * SBP2 target driver (SCSI over IEEE1394 in target mode)
+ *
+ * Copyright (C) 2011 Chris Boot <bootc@xxxxxxxxx>
+ *
+ * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#define KMSG_COMPONENT "sbp_target"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/firewire.h>
+#include <linux/firewire-constants.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_tcq.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_fabric.h>
+#include <target/target_core_fabric_configfs.h>
+#include <target/target_core_configfs.h>
+
+#include "sbp_base.h"
+#include "sbp_target_agent.h"
+#include "sbp_scsi_cmnd.h"
+
+/*
+ * Simple wrapper around fw_run_transaction that retries the transaction several
+ * times in case of failure, with an exponential backoff.
+ */
+int sbp_run_transaction(struct fw_card *card, int tcode, int destination_id,
+ int generation, int speed, unsigned long long offset,
+ void *payload, size_t length)
+{
+ int attempt, ret, delay;
+
+ for (attempt = 1; attempt <= 5; attempt++) {
+ ret = fw_run_transaction(card, tcode, destination_id,
+ generation, speed, offset, payload, length);
+
+ switch (ret) {
+ case RCODE_COMPLETE:
+ case RCODE_TYPE_ERROR:
+ case RCODE_ADDRESS_ERROR:
+ case RCODE_GENERATION:
+ return ret;
+
+ default:
+ delay = 5 * attempt * attempt;
+ usleep_range(delay, delay * 2);
+ }
+ }
+
+ return ret;
+}
+
+/*
+ * Wrapper around sbp_run_transaction that gets the card, destination,
+ * generation and speed out of the request's session.
+ */
+static int sbp_run_request_transaction(struct sbp_target_request *req,
+ int tcode, unsigned long long offset, void *payload,
+ size_t length)
+{
+ struct sbp_login_descriptor *login = req->login;
+ struct sbp_session *sess = login->sess;
+ struct fw_card *card;
+ int node_id, generation, speed, ret;
+
+ spin_lock_bh(&sess->lock);
+ card = fw_card_get(sess->card);
+ node_id = sess->node_id;
+ generation = sess->generation;
+ speed = sess->speed;
+ spin_unlock_bh(&sess->lock);
+
+ ret = sbp_run_transaction(card, tcode, node_id, generation, speed,
+ offset, payload, length);
+
+ fw_card_put(card);
+
+ return ret;
+}
+
+static int sbp_fetch_command(struct sbp_target_request *req)
+{
+ int ret, cmd_len, copy_len;
+
+ cmd_len = scsi_command_size(req->orb.command_block);
+
+ req->cmd_buf = kmalloc(cmd_len, GFP_KERNEL);
+ if (!req->cmd_buf)
+ return -ENOMEM;
+
+ memcpy(req->cmd_buf, req->orb.command_block,
+ min_t(int, cmd_len, sizeof(req->orb.command_block)));
+
+ if (cmd_len > sizeof(req->orb.command_block)) {
+ pr_debug("sbp_fetch_command: filling in long command\n");
+ copy_len = cmd_len - sizeof(req->orb.command_block);
+
+ ret = sbp_run_request_transaction(req,
+ TCODE_READ_BLOCK_REQUEST,
+ req->orb_pointer + sizeof(req->orb),
+ req->cmd_buf + sizeof(req->orb.command_block),
+ copy_len);
+ if (ret != RCODE_COMPLETE)
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int sbp_fetch_page_table(struct sbp_target_request *req)
+{
+ int pg_tbl_sz, ret;
+ struct sbp_page_table_entry *pg_tbl;
+
+ if (!CMDBLK_ORB_PG_TBL_PRESENT(be32_to_cpu(req->orb.misc)))
+ return 0;
+
+ pg_tbl_sz = CMDBLK_ORB_DATA_SIZE(be32_to_cpu(req->orb.misc)) *
+ sizeof(struct sbp_page_table_entry);
+
+ pg_tbl = kmalloc(pg_tbl_sz, GFP_KERNEL);
+ if (!pg_tbl)
+ return -ENOMEM;
+
+ ret = sbp_run_request_transaction(req, TCODE_READ_BLOCK_REQUEST,
+ sbp2_pointer_to_addr(&req->orb.data_descriptor),
+ pg_tbl, pg_tbl_sz);
+ if (ret != RCODE_COMPLETE) {
+ kfree(pg_tbl);
+ return -EIO;
+ }
+
+ req->pg_tbl = pg_tbl;
+ return 0;
+}
+
+static void sbp_calc_data_length_direction(struct sbp_target_request *req,
+ u32 *data_len, enum dma_data_direction *data_dir)
+{
+ int data_size, direction, idx;
+
+ data_size = CMDBLK_ORB_DATA_SIZE(be32_to_cpu(req->orb.misc));
+ direction = CMDBLK_ORB_DIRECTION(be32_to_cpu(req->orb.misc));
+
+ if (!data_size) {
+ *data_len = 0;
+ *data_dir = DMA_NONE;
+ return;
+ }
+
+ *data_dir = direction ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
+
+ if (req->pg_tbl) {
+ *data_len = 0;
+ for (idx = 0; idx < data_size; idx++) {
+ *data_len += be16_to_cpu(
+ req->pg_tbl[idx].segment_length);
+ }
+ } else {
+ *data_len = data_size;
+ }
+}
+
+void sbp_handle_command(struct sbp_target_request *req)
+{
+ struct sbp_login_descriptor *login = req->login;
+ struct sbp_session *sess = login->sess;
+ int ret, unpacked_lun;
+ u32 data_length;
+ enum dma_data_direction data_dir;
+
+ ret = sbp_fetch_command(req);
+ if (ret) {
+ pr_debug("sbp_handle_command: fetch command failed: %d\n", ret);
+ req->status.status |= cpu_to_be32(
+ STATUS_BLOCK_RESP(STATUS_RESP_TRANSPORT_FAILURE) |
+ STATUS_BLOCK_DEAD(0) |
+ STATUS_BLOCK_LEN(1) |
+ STATUS_BLOCK_SBP_STATUS(SBP_STATUS_UNSPECIFIED_ERROR));
+ sbp_send_status(req);
+ sbp_free_request(req);
+ return;
+ }
+
+ ret = sbp_fetch_page_table(req);
+ if (ret) {
+ pr_debug("sbp_handle_command: fetch page table failed: %d\n",
+ ret);
+ req->status.status |= cpu_to_be32(
+ STATUS_BLOCK_RESP(STATUS_RESP_TRANSPORT_FAILURE) |
+ STATUS_BLOCK_DEAD(0) |
+ STATUS_BLOCK_LEN(1) |
+ STATUS_BLOCK_SBP_STATUS(SBP_STATUS_UNSPECIFIED_ERROR));
+ sbp_send_status(req);
+ sbp_free_request(req);
+ return;
+ }
+
+ unpacked_lun = req->login->lun->unpacked_lun;
+ sbp_calc_data_length_direction(req, &data_length, &data_dir);
+
+ pr_debug("sbp_handle_command ORB:0x%llx unpacked_lun:%d data_len:%d data_dir:%d\n",
+ req->orb_pointer, unpacked_lun, data_length, data_dir);
+
+ target_submit_cmd(&req->se_cmd, sess->se_sess, req->cmd_buf,
+ req->sense_buf, unpacked_lun, data_length,
+ MSG_SIMPLE_TAG, data_dir, 0);
+}
+
+/*
+ * DMA_TO_DEVICE = read from initiator (SCSI WRITE)
+ * DMA_FROM_DEVICE = write to initiator (SCSI READ)
+ */
+int sbp_rw_data(struct sbp_target_request *req)
+{
+ struct sbp_session *sess = req->login->sess;
+ int tcode, sg_miter_flags, max_payload, pg_size, speed, node_id,
+ generation, num_pte, length, tfr_length,
+ rcode = RCODE_COMPLETE;
+ struct sbp_page_table_entry *pte;
+ unsigned long long offset;
+ struct fw_card *card;
+ struct sg_mapping_iter iter;
+
+ if (req->se_cmd.data_direction == DMA_FROM_DEVICE) {
+ tcode = TCODE_WRITE_BLOCK_REQUEST;
+ sg_miter_flags = SG_MITER_FROM_SG;
+ } else {
+ tcode = TCODE_READ_BLOCK_REQUEST;
+ sg_miter_flags = SG_MITER_TO_SG;
+ }
+
+ max_payload = 4 << CMDBLK_ORB_MAX_PAYLOAD(be32_to_cpu(req->orb.misc));
+ speed = CMDBLK_ORB_SPEED(be32_to_cpu(req->orb.misc));
+
+ pg_size = CMDBLK_ORB_PG_SIZE(be32_to_cpu(req->orb.misc));
+ if (pg_size) {
+ pr_err("sbp_run_transaction: page size ignored\n");
+ pg_size = 0x100 << pg_size;
+ }
+
+ spin_lock_bh(&sess->lock);
+ card = fw_card_get(sess->card);
+ node_id = sess->node_id;
+ generation = sess->generation;
+ spin_unlock_bh(&sess->lock);
+
+ if (req->pg_tbl) {
+ pte = req->pg_tbl;
+ num_pte = CMDBLK_ORB_DATA_SIZE(be32_to_cpu(req->orb.misc));
+
+ offset = 0;
+ length = 0;
+ } else {
+ pte = NULL;
+ num_pte = 0;
+
+ offset = sbp2_pointer_to_addr(&req->orb.data_descriptor);
+ length = req->se_cmd.data_length;
+ }
+
+ sg_miter_start(&iter, req->se_cmd.t_data_sg, req->se_cmd.t_data_nents,
+ sg_miter_flags);
+
+ while (length || num_pte) {
+ if (!length) {
+ offset = (u64)be16_to_cpu(pte->segment_base_hi) << 32 |
+ be32_to_cpu(pte->segment_base_lo);
+ length = be16_to_cpu(pte->segment_length);
+
+ pte++;
+ num_pte--;
+ }
+
+ sg_miter_next(&iter);
+
+ tfr_length = min3(length, max_payload, (int)iter.length);
+
+ /* FIXME: take page_size into account */
+
+ rcode = sbp_run_transaction(card, tcode, node_id,
+ generation, speed,
+ offset, iter.addr, tfr_length);
+
+ if (rcode != RCODE_COMPLETE)
+ break;
+
+ length -= tfr_length;
+ offset += tfr_length;
+ iter.consumed = tfr_length;
+ }
+
+ sg_miter_stop(&iter);
+ fw_card_put(card);
+
+ if (rcode == RCODE_COMPLETE) {
+ WARN_ON(length != 0);
+ return 0;
+ } else {
+ return -EIO;
+ }
+}
+
+int sbp_send_status(struct sbp_target_request *req)
+{
+ int ret, length;
+ struct sbp_login_descriptor *login = req->login;
+
+ length = (((be32_to_cpu(req->status.status) >> 24) & 0x07) + 1) * 4;
+
+ ret = sbp_run_request_transaction(req, TCODE_WRITE_BLOCK_REQUEST,
+ login->status_fifo_addr, &req->status, length);
+ if (ret != RCODE_COMPLETE) {
+ pr_debug("sbp_send_status: write failed: 0x%x\n", ret);
+ return -EIO;
+ }
+
+ pr_debug("sbp_send_status: status write complete for ORB: 0x%llx\n",
+ req->orb_pointer);
+
+ return 0;
+}
+
+static void sbp_sense_mangle(struct sbp_target_request *req)
+{
+ struct se_cmd *se_cmd = &req->se_cmd;
+ u8 *sense = req->sense_buf;
+ u8 *status = req->status.data;
+
+ WARN_ON(se_cmd->scsi_sense_length < 18);
+
+ switch (sense[0] & 0x7f) { /* sfmt */
+ case 0x70: /* current, fixed */
+ status[0] = 0 << 6;
+ break;
+ case 0x71: /* deferred, fixed */
+ status[0] = 1 << 6;
+ break;
+ case 0x72: /* current, descriptor */
+ case 0x73: /* deferred, descriptor */
+ default:
+ /*
+ * TODO: SBP-3 specifies what we should do with descriptor
+ * format sense data
+ */
+ pr_err("sbp_send_sense: unknown sense format: 0x%x\n",
+ sense[0]);
+ req->status.status |= cpu_to_be32(
+ STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
+ STATUS_BLOCK_DEAD(0) |
+ STATUS_BLOCK_LEN(1) |
+ STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQUEST_ABORTED));
+ return;
+ }
+
+ status[0] |= se_cmd->scsi_status & 0x3f;/* status */
+ status[1] =
+ (sense[0] & 0x80) | /* valid */
+ ((sense[2] & 0xe0) >> 1) | /* mark, eom, ili */
+ (sense[2] & 0x0f); /* sense_key */
+ status[2] = se_cmd->scsi_asc; /* sense_code */
+ status[3] = se_cmd->scsi_ascq; /* sense_qualifier */
+
+ /* information */
+ status[4] = sense[3];
+ status[5] = sense[4];
+ status[6] = sense[5];
+ status[7] = sense[6];
+
+ /* CDB-dependent */
+ status[8] = sense[8];
+ status[9] = sense[9];
+ status[10] = sense[10];
+ status[11] = sense[11];
+
+ /* fru */
+ status[12] = sense[14];
+
+ /* sense_key-dependent */
+ status[13] = sense[15];
+ status[14] = sense[16];
+ status[15] = sense[17];
+
+ req->status.status |= cpu_to_be32(
+ STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
+ STATUS_BLOCK_DEAD(0) |
+ STATUS_BLOCK_LEN(5) |
+ STATUS_BLOCK_SBP_STATUS(SBP_STATUS_OK));
+}
+
+int sbp_send_sense(struct sbp_target_request *req)
+{
+ struct se_cmd *se_cmd = &req->se_cmd;
+
+ if (se_cmd->scsi_sense_length) {
+ sbp_sense_mangle(req);
+ } else {
+ req->status.status |= cpu_to_be32(
+ STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
+ STATUS_BLOCK_DEAD(0) |
+ STATUS_BLOCK_LEN(1) |
+ STATUS_BLOCK_SBP_STATUS(SBP_STATUS_OK));
+ }
+
+ return sbp_send_status(req);
+}
+
+void sbp_free_request(struct sbp_target_request *req)
+{
+ kfree(req->pg_tbl);
+ kfree(req->cmd_buf);
+ kfree(req);
+}
diff --git a/drivers/target/sbp/sbp_scsi_cmnd.h b/drivers/target/sbp/sbp_scsi_cmnd.h
new file mode 100644
index 0000000..d02f4ca
--- /dev/null
+++ b/drivers/target/sbp/sbp_scsi_cmnd.h
@@ -0,0 +1,12 @@
+
+#include "sbp_target_agent.h"
+
+int sbp_run_transaction(struct fw_card *card, int tcode, int destination_id,
+ int generation, int speed, unsigned long long offset,
+ void *payload, size_t length);
+
+void sbp_handle_command(struct sbp_target_request *req);
+int sbp_rw_data(struct sbp_target_request *req);
+int sbp_send_status(struct sbp_target_request *req);
+int sbp_send_sense(struct sbp_target_request *req);
+void sbp_free_request(struct sbp_target_request *req);
--
1.7.9.5
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