From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
This patch adds the RAMDISK_DR (memory map) and RAMDISK_MCP (memcpy) subsystem plugin
for accessing internally allocated struct scatterlist memory as a TCM storage object.
Note that this is the only TCM subsystem plugin that is still built into target_core_mod.ko
Signed-off-by: Nicholas A. Bellinger <nab@xxxxxxxxxxxxxxx>
---
drivers/target/target_core_rd.c | 1091 +++++++++++++++++++++++++++++++++++++++
drivers/target/target_core_rd.h | 73 +++
2 files changed, 1164 insertions(+), 0 deletions(-)
create mode 100644 drivers/target/target_core_rd.c
create mode 100644 drivers/target/target_core_rd.h
diff --git a/drivers/target/target_core_rd.c b/drivers/target/target_core_rd.c
new file mode 100644
index 0000000..979aebf
--- /dev/null
+++ b/drivers/target/target_core_rd.c
@@ -0,0 +1,1091 @@
+/*******************************************************************************
+ * Filename: target_core_rd.c
+ *
+ * This file contains the Storage Engine <-> Ramdisk transport
+ * specific functions.
+ *
+ * Copyright (c) 2003, 2004, 2005 PyX Technologies, Inc.
+ * Copyright (c) 2005, 2006, 2007 SBE, Inc.
+ * Copyright (c) 2007-2010 Rising Tide Systems
+ * Copyright (c) 2008-2010 Linux-iSCSI.org
+ *
+ * Nicholas A. Bellinger <nab@xxxxxxxxxx>
+ *
+ * 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.
+ *
+ ******************************************************************************/
+
+#include <linux/version.h>
+#include <linux/string.h>
+#include <linux/parser.h>
+#include <linux/timer.h>
+#include <linux/blkdev.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/smp_lock.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_host.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_device.h>
+#include <target/target_core_transport.h>
+#include <target/target_core_fabric_ops.h>
+
+#include "target_core_rd.h"
+
+static struct se_subsystem_api rd_dr_template;
+static struct se_subsystem_api rd_mcp_template;
+
+/* #define DEBUG_RAMDISK_MCP */
+/* #define DEBUG_RAMDISK_DR */
+
+/* rd_attach_hba(): (Part of se_subsystem_api_t template)
+ *
+ *
+ */
+static int rd_attach_hba(struct se_hba *hba, u32 host_id)
+{
+ struct rd_host *rd_host;
+
+ rd_host = kzalloc(sizeof(struct rd_host), GFP_KERNEL);
+ if (!(rd_host)) {
+ printk(KERN_ERR "Unable to allocate memory for struct rd_host\n");
+ return -ENOMEM;
+ }
+
+ rd_host->rd_host_id = host_id;
+
+ atomic_set(&hba->left_queue_depth, RD_HBA_QUEUE_DEPTH);
+ atomic_set(&hba->max_queue_depth, RD_HBA_QUEUE_DEPTH);
+ hba->hba_ptr = (void *) rd_host;
+
+ printk(KERN_INFO "CORE_HBA[%d] - TCM Ramdisk HBA Driver %s on"
+ " Generic Target Core Stack %s\n", hba->hba_id,
+ RD_HBA_VERSION, TARGET_CORE_MOD_VERSION);
+ printk(KERN_INFO "CORE_HBA[%d] - Attached Ramdisk HBA: %u to Generic"
+ " Target Core TCQ Depth: %d MaxSectors: %u\n", hba->hba_id,
+ rd_host->rd_host_id, atomic_read(&hba->max_queue_depth),
+ RD_MAX_SECTORS);
+
+ return 0;
+}
+
+static void rd_detach_hba(struct se_hba *hba)
+{
+ struct rd_host *rd_host = hba->hba_ptr;
+
+ printk(KERN_INFO "CORE_HBA[%d] - Detached Ramdisk HBA: %u from"
+ " Generic Target Core\n", hba->hba_id, rd_host->rd_host_id);
+
+ kfree(rd_host);
+ hba->hba_ptr = NULL;
+}
+
+/* rd_release_device_space():
+ *
+ *
+ */
+static void rd_release_device_space(struct rd_dev *rd_dev)
+{
+ u32 i, j, page_count = 0, sg_per_table;
+ struct rd_dev_sg_table *sg_table;
+ struct page *pg;
+ struct scatterlist *sg;
+
+ if (!rd_dev->sg_table_array || !rd_dev->sg_table_count)
+ return;
+
+ sg_table = rd_dev->sg_table_array;
+
+ for (i = 0; i < rd_dev->sg_table_count; i++) {
+ sg = sg_table[i].sg_table;
+ sg_per_table = sg_table[i].rd_sg_count;
+
+ for (j = 0; j < sg_per_table; j++) {
+ pg = sg_page(&sg[j]);
+ if ((pg)) {
+ __free_page(pg);
+ page_count++;
+ }
+ }
+
+ kfree(sg);
+ }
+
+ printk(KERN_INFO "CORE_RD[%u] - Released device space for Ramdisk"
+ " Device ID: %u, pages %u in %u tables total bytes %lu\n",
+ rd_dev->rd_host->rd_host_id, rd_dev->rd_dev_id, page_count,
+ rd_dev->sg_table_count, (unsigned long)page_count * PAGE_SIZE);
+
+ kfree(sg_table);
+ rd_dev->sg_table_array = NULL;
+ rd_dev->sg_table_count = 0;
+}
+
+
+/* rd_build_device_space():
+ *
+ *
+ */
+static int rd_build_device_space(struct rd_dev *rd_dev)
+{
+ u32 i = 0, j, page_offset = 0, sg_per_table, sg_tables, total_sg_needed;
+ u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
+ sizeof(struct scatterlist));
+ struct rd_dev_sg_table *sg_table;
+ struct page *pg;
+ struct scatterlist *sg;
+
+ if (rd_dev->rd_page_count <= 0) {
+ printk(KERN_ERR "Illegal page count: %u for Ramdisk device\n",
+ rd_dev->rd_page_count);
+ return -1;
+ }
+ total_sg_needed = rd_dev->rd_page_count;
+
+ sg_tables = (total_sg_needed / max_sg_per_table) + 1;
+
+ sg_table = kzalloc(sg_tables * sizeof(struct rd_dev_sg_table), GFP_KERNEL);
+ if (!(sg_table)) {
+ printk(KERN_ERR "Unable to allocate memory for Ramdisk"
+ " scatterlist tables\n");
+ return -1;
+ }
+
+ rd_dev->sg_table_array = sg_table;
+ rd_dev->sg_table_count = sg_tables;
+
+ while (total_sg_needed) {
+ sg_per_table = (total_sg_needed > max_sg_per_table) ?
+ max_sg_per_table : total_sg_needed;
+
+ sg = kzalloc(sg_per_table * sizeof(struct scatterlist),
+ GFP_KERNEL);
+ if (!(sg)) {
+ printk(KERN_ERR "Unable to allocate scatterlist array"
+ " for struct rd_dev\n");
+ return -1;
+ }
+
+ sg_init_table((struct scatterlist *)&sg[0], sg_per_table);
+
+ sg_table[i].sg_table = sg;
+ sg_table[i].rd_sg_count = sg_per_table;
+ sg_table[i].page_start_offset = page_offset;
+ sg_table[i++].page_end_offset = (page_offset + sg_per_table)
+ - 1;
+
+ for (j = 0; j < sg_per_table; j++) {
+ pg = alloc_pages(GFP_KERNEL, 0);
+ if (!(pg)) {
+ printk(KERN_ERR "Unable to allocate scatterlist"
+ " pages for struct rd_dev_sg_table\n");
+ return -1;
+ }
+ sg_assign_page(&sg[j], pg);
+ sg[j].length = PAGE_SIZE;
+ }
+
+ page_offset += sg_per_table;
+ total_sg_needed -= sg_per_table;
+ }
+
+ printk(KERN_INFO "CORE_RD[%u] - Built Ramdisk Device ID: %u space of"
+ " %u pages in %u tables\n", rd_dev->rd_host->rd_host_id,
+ rd_dev->rd_dev_id, rd_dev->rd_page_count,
+ rd_dev->sg_table_count);
+
+ return 0;
+}
+
+static void *rd_allocate_virtdevice(
+ struct se_hba *hba,
+ const char *name,
+ int rd_direct)
+{
+ struct rd_dev *rd_dev;
+ struct rd_host *rd_host = hba->hba_ptr;
+
+ rd_dev = kzalloc(sizeof(struct rd_dev), GFP_KERNEL);
+ if (!(rd_dev)) {
+ printk(KERN_ERR "Unable to allocate memory for struct rd_dev\n");
+ return NULL;
+ }
+
+ rd_dev->rd_host = rd_host;
+ rd_dev->rd_direct = rd_direct;
+
+ return rd_dev;
+}
+
+static void *rd_DIRECT_allocate_virtdevice(struct se_hba *hba, const char *name)
+{
+ return rd_allocate_virtdevice(hba, name, 1);
+}
+
+static void *rd_MEMCPY_allocate_virtdevice(struct se_hba *hba, const char *name)
+{
+ return rd_allocate_virtdevice(hba, name, 0);
+}
+
+/* rd_create_virtdevice():
+ *
+ *
+ */
+static struct se_device *rd_create_virtdevice(
+ struct se_hba *hba,
+ struct se_subsystem_dev *se_dev,
+ void *p,
+ int rd_direct)
+{
+ struct se_device *dev;
+ struct se_dev_limits dev_limits;
+ struct rd_dev *rd_dev = p;
+ struct rd_host *rd_host = hba->hba_ptr;
+ int dev_flags = 0;
+ char prod[16], rev[4];
+
+ memset(&dev_limits, 0, sizeof(struct se_dev_limits));
+
+ if (rd_build_device_space(rd_dev) < 0)
+ goto fail;
+
+ snprintf(prod, 16, "RAMDISK-%s", (rd_dev->rd_direct) ? "DR" : "MCP");
+ snprintf(rev, 4, "%s", (rd_dev->rd_direct) ? RD_DR_VERSION :
+ RD_MCP_VERSION);
+
+ dev_limits.limits.logical_block_size = RD_BLOCKSIZE;
+ dev_limits.limits.max_hw_sectors = RD_MAX_SECTORS;
+ dev_limits.limits.max_sectors = RD_MAX_SECTORS;
+ dev_limits.hw_queue_depth = RD_MAX_DEVICE_QUEUE_DEPTH;
+ dev_limits.queue_depth = RD_DEVICE_QUEUE_DEPTH;
+
+ dev = transport_add_device_to_core_hba(hba,
+ (rd_dev->rd_direct) ? &rd_dr_template :
+ &rd_mcp_template, se_dev, dev_flags, (void *)rd_dev,
+ &dev_limits, prod, rev);
+ if (!(dev))
+ goto fail;
+
+ rd_dev->rd_dev_id = rd_host->rd_host_dev_id_count++;
+ rd_dev->rd_queue_depth = dev->queue_depth;
+
+ printk(KERN_INFO "CORE_RD[%u] - Added TCM %s Ramdisk Device ID: %u of"
+ " %u pages in %u tables, %lu total bytes\n",
+ rd_host->rd_host_id, (!rd_dev->rd_direct) ? "MEMCPY" :
+ "DIRECT", rd_dev->rd_dev_id, rd_dev->rd_page_count,
+ rd_dev->sg_table_count,
+ (unsigned long)(rd_dev->rd_page_count * PAGE_SIZE));
+
+ return dev;
+
+fail:
+ rd_release_device_space(rd_dev);
+ return NULL;
+}
+
+static struct se_device *rd_DIRECT_create_virtdevice(
+ struct se_hba *hba,
+ struct se_subsystem_dev *se_dev,
+ void *p)
+{
+ return rd_create_virtdevice(hba, se_dev, p, 1);
+}
+
+static struct se_device *rd_MEMCPY_create_virtdevice(
+ struct se_hba *hba,
+ struct se_subsystem_dev *se_dev,
+ void *p)
+{
+ return rd_create_virtdevice(hba, se_dev, p, 0);
+}
+
+/* rd_free_device(): (Part of se_subsystem_api_t template)
+ *
+ *
+ */
+static void rd_free_device(void *p)
+{
+ struct rd_dev *rd_dev = p;
+
+ rd_release_device_space(rd_dev);
+ kfree(rd_dev);
+}
+
+static inline struct rd_request *RD_REQ(struct se_task *task)
+{
+ return container_of(task, struct rd_request, rd_task);
+}
+
+static struct se_task *
+rd_alloc_task(struct se_cmd *cmd)
+{
+ struct rd_request *rd_req;
+
+ rd_req = kzalloc(sizeof(struct rd_request), GFP_KERNEL);
+ if (!rd_req) {
+ printk(KERN_ERR "Unable to allocate struct rd_request\n");
+ return NULL;
+ }
+ rd_req->rd_dev = SE_DEV(cmd)->dev_ptr;
+
+ return &rd_req->rd_task;
+}
+
+/* rd_get_sg_table():
+ *
+ *
+ */
+static struct rd_dev_sg_table *rd_get_sg_table(struct rd_dev *rd_dev, u32 page)
+{
+ u32 i;
+ struct rd_dev_sg_table *sg_table;
+
+ for (i = 0; i < rd_dev->sg_table_count; i++) {
+ sg_table = &rd_dev->sg_table_array[i];
+ if ((sg_table->page_start_offset <= page) &&
+ (sg_table->page_end_offset >= page))
+ return sg_table;
+ }
+
+ printk(KERN_ERR "Unable to locate struct rd_dev_sg_table for page: %u\n",
+ page);
+
+ return NULL;
+}
+
+/* rd_MEMCPY_read():
+ *
+ *
+ */
+static int rd_MEMCPY_read(struct rd_request *req)
+{
+ struct se_task *task = &req->rd_task;
+ struct rd_dev *dev = req->rd_dev;
+ struct rd_dev_sg_table *table;
+ struct scatterlist *sg_d, *sg_s;
+ void *dst, *src;
+ u32 i = 0, j = 0, dst_offset = 0, src_offset = 0;
+ u32 length, page_end = 0, table_sg_end;
+ u32 rd_offset = req->rd_offset;
+
+ table = rd_get_sg_table(dev, req->rd_page);
+ if (!(table))
+ return -1;
+
+ table_sg_end = (table->page_end_offset - req->rd_page);
+ sg_d = task->task_sg;
+ sg_s = &table->sg_table[req->rd_page - table->page_start_offset];
+#ifdef DEBUG_RAMDISK_MCP
+ printk(KERN_INFO "RD[%u]: Read LBA: %llu, Size: %u Page: %u, Offset:"
+ " %u\n", dev->rd_dev_id, task->task_lba, req->rd_size,
+ req->rd_page, req->rd_offset);
+#endif
+ src_offset = rd_offset;
+
+ while (req->rd_size) {
+ if ((sg_d[i].length - dst_offset) <
+ (sg_s[j].length - src_offset)) {
+ length = (sg_d[i].length - dst_offset);
+#ifdef DEBUG_RAMDISK_MCP
+ printk(KERN_INFO "Step 1 - sg_d[%d]: %p length: %d"
+ " offset: %u sg_s[%d].length: %u\n", i,
+ &sg_d[i], sg_d[i].length, sg_d[i].offset, j,
+ sg_s[j].length);
+ printk(KERN_INFO "Step 1 - length: %u dst_offset: %u"
+ " src_offset: %u\n", length, dst_offset,
+ src_offset);
+#endif
+ if (length > req->rd_size)
+ length = req->rd_size;
+
+ dst = sg_virt(&sg_d[i++]) + dst_offset;
+ if (!dst)
+ BUG();
+
+ src = sg_virt(&sg_s[j]) + src_offset;
+ if (!src)
+ BUG();
+
+ dst_offset = 0;
+ src_offset = length;
+ page_end = 0;
+ } else {
+ length = (sg_s[j].length - src_offset);
+#ifdef DEBUG_RAMDISK_MCP
+ printk(KERN_INFO "Step 2 - sg_d[%d]: %p length: %d"
+ " offset: %u sg_s[%d].length: %u\n", i,
+ &sg_d[i], sg_d[i].length, sg_d[i].offset,
+ j, sg_s[j].length);
+ printk(KERN_INFO "Step 2 - length: %u dst_offset: %u"
+ " src_offset: %u\n", length, dst_offset,
+ src_offset);
+#endif
+ if (length > req->rd_size)
+ length = req->rd_size;
+
+ dst = sg_virt(&sg_d[i]) + dst_offset;
+ if (!dst)
+ BUG();
+
+ if (sg_d[i].length == length) {
+ i++;
+ dst_offset = 0;
+ } else
+ dst_offset = length;
+
+ src = sg_virt(&sg_s[j++]) + src_offset;
+ if (!src)
+ BUG();
+
+ src_offset = 0;
+ page_end = 1;
+ }
+
+ memcpy(dst, src, length);
+
+#ifdef DEBUG_RAMDISK_MCP
+ printk(KERN_INFO "page: %u, remaining size: %u, length: %u,"
+ " i: %u, j: %u\n", req->rd_page,
+ (req->rd_size - length), length, i, j);
+#endif
+ req->rd_size -= length;
+ if (!(req->rd_size))
+ return 0;
+
+ if (!page_end)
+ continue;
+
+ if (++req->rd_page <= table->page_end_offset) {
+#ifdef DEBUG_RAMDISK_MCP
+ printk(KERN_INFO "page: %u in same page table\n",
+ req->rd_page);
+#endif
+ continue;
+ }
+#ifdef DEBUG_RAMDISK_MCP
+ printk(KERN_INFO "getting new page table for page: %u\n",
+ req->rd_page);
+#endif
+ table = rd_get_sg_table(dev, req->rd_page);
+ if (!(table))
+ return -1;
+
+ sg_s = &table->sg_table[j = 0];
+ }
+
+ return 0;
+}
+
+/* rd_MEMCPY_write():
+ *
+ *
+ */
+static int rd_MEMCPY_write(struct rd_request *req)
+{
+ struct se_task *task = &req->rd_task;
+ struct rd_dev *dev = req->rd_dev;
+ struct rd_dev_sg_table *table;
+ struct scatterlist *sg_d, *sg_s;
+ void *dst, *src;
+ u32 i = 0, j = 0, dst_offset = 0, src_offset = 0;
+ u32 length, page_end = 0, table_sg_end;
+ u32 rd_offset = req->rd_offset;
+
+ table = rd_get_sg_table(dev, req->rd_page);
+ if (!(table))
+ return -1;
+
+ table_sg_end = (table->page_end_offset - req->rd_page);
+ sg_d = &table->sg_table[req->rd_page - table->page_start_offset];
+ sg_s = task->task_sg;
+#ifdef DEBUG_RAMDISK_MCP
+ printk(KERN_INFO "RD[%d] Write LBA: %llu, Size: %u, Page: %u,"
+ " Offset: %u\n", dev->rd_dev_id, task->task_lba, req->rd_size,
+ req->rd_page, req->rd_offset);
+#endif
+ dst_offset = rd_offset;
+
+ while (req->rd_size) {
+ if ((sg_s[i].length - src_offset) <
+ (sg_d[j].length - dst_offset)) {
+ length = (sg_s[i].length - src_offset);
+#ifdef DEBUG_RAMDISK_MCP
+ printk(KERN_INFO "Step 1 - sg_s[%d]: %p length: %d"
+ " offset: %d sg_d[%d].length: %u\n", i,
+ &sg_s[i], sg_s[i].length, sg_s[i].offset,
+ j, sg_d[j].length);
+ printk(KERN_INFO "Step 1 - length: %u src_offset: %u"
+ " dst_offset: %u\n", length, src_offset,
+ dst_offset);
+#endif
+ if (length > req->rd_size)
+ length = req->rd_size;
+
+ src = sg_virt(&sg_s[i++]) + src_offset;
+ if (!src)
+ BUG();
+
+ dst = sg_virt(&sg_d[j]) + dst_offset;
+ if (!dst)
+ BUG();
+
+ src_offset = 0;
+ dst_offset = length;
+ page_end = 0;
+ } else {
+ length = (sg_d[j].length - dst_offset);
+#ifdef DEBUG_RAMDISK_MCP
+ printk(KERN_INFO "Step 2 - sg_s[%d]: %p length: %d"
+ " offset: %d sg_d[%d].length: %u\n", i,
+ &sg_s[i], sg_s[i].length, sg_s[i].offset,
+ j, sg_d[j].length);
+ printk(KERN_INFO "Step 2 - length: %u src_offset: %u"
+ " dst_offset: %u\n", length, src_offset,
+ dst_offset);
+#endif
+ if (length > req->rd_size)
+ length = req->rd_size;
+
+ src = sg_virt(&sg_s[i]) + src_offset;
+ if (!src)
+ BUG();
+
+ if (sg_s[i].length == length) {
+ i++;
+ src_offset = 0;
+ } else
+ src_offset = length;
+
+ dst = sg_virt(&sg_d[j++]) + dst_offset;
+ if (!dst)
+ BUG();
+
+ dst_offset = 0;
+ page_end = 1;
+ }
+
+ memcpy(dst, src, length);
+
+#ifdef DEBUG_RAMDISK_MCP
+ printk(KERN_INFO "page: %u, remaining size: %u, length: %u,"
+ " i: %u, j: %u\n", req->rd_page,
+ (req->rd_size - length), length, i, j);
+#endif
+ req->rd_size -= length;
+ if (!(req->rd_size))
+ return 0;
+
+ if (!page_end)
+ continue;
+
+ if (++req->rd_page <= table->page_end_offset) {
+#ifdef DEBUG_RAMDISK_MCP
+ printk(KERN_INFO "page: %u in same page table\n",
+ req->rd_page);
+#endif
+ continue;
+ }
+#ifdef DEBUG_RAMDISK_MCP
+ printk(KERN_INFO "getting new page table for page: %u\n",
+ req->rd_page);
+#endif
+ table = rd_get_sg_table(dev, req->rd_page);
+ if (!(table))
+ return -1;
+
+ sg_d = &table->sg_table[j = 0];
+ }
+
+ return 0;
+}
+
+/* rd_MEMCPY_do_task(): (Part of se_subsystem_api_t template)
+ *
+ *
+ */
+static int rd_MEMCPY_do_task(struct se_task *task)
+{
+ struct se_device *dev = task->se_dev;
+ struct rd_request *req = RD_REQ(task);
+ unsigned long long lba;
+ int ret;
+
+ req->rd_page = (task->task_lba * DEV_ATTRIB(dev)->block_size) / PAGE_SIZE;
+ lba = task->task_lba;
+ req->rd_offset = (do_div(lba,
+ (PAGE_SIZE / DEV_ATTRIB(dev)->block_size))) *
+ DEV_ATTRIB(dev)->block_size;
+ req->rd_size = task->task_size;
+
+ if (task->task_data_direction == DMA_FROM_DEVICE)
+ ret = rd_MEMCPY_read(req);
+ else
+ ret = rd_MEMCPY_write(req);
+
+ if (ret != 0)
+ return ret;
+
+ task->task_scsi_status = GOOD;
+ transport_complete_task(task, 1);
+
+ return PYX_TRANSPORT_SENT_TO_TRANSPORT;
+}
+
+/* rd_DIRECT_with_offset():
+ *
+ *
+ */
+static int rd_DIRECT_with_offset(
+ struct se_task *task,
+ struct list_head *se_mem_list,
+ u32 *se_mem_cnt,
+ u32 *task_offset)
+{
+ struct rd_request *req = RD_REQ(task);
+ struct rd_dev *dev = req->rd_dev;
+ struct rd_dev_sg_table *table;
+ struct se_mem *se_mem;
+ struct scatterlist *sg_s;
+ u32 j = 0, set_offset = 1;
+ u32 get_next_table = 0, offset_length, table_sg_end;
+
+ table = rd_get_sg_table(dev, req->rd_page);
+ if (!(table))
+ return -1;
+
+ table_sg_end = (table->page_end_offset - req->rd_page);
+ sg_s = &table->sg_table[req->rd_page - table->page_start_offset];
+#ifdef DEBUG_RAMDISK_DR
+ printk(KERN_INFO "%s DIRECT LBA: %llu, Size: %u Page: %u, Offset: %u\n",
+ (task->task_data_direction == DMA_TO_DEVICE) ?
+ "Write" : "Read",
+ task->task_lba, req->rd_size, req->rd_page, req->rd_offset);
+#endif
+ while (req->rd_size) {
+ se_mem = kmem_cache_zalloc(se_mem_cache, GFP_KERNEL);
+ if (!(se_mem)) {
+ printk(KERN_ERR "Unable to allocate struct se_mem\n");
+ return -1;
+ }
+ INIT_LIST_HEAD(&se_mem->se_list);
+
+ if (set_offset) {
+ offset_length = sg_s[j].length - req->rd_offset;
+ if (offset_length > req->rd_size)
+ offset_length = req->rd_size;
+
+ se_mem->se_page = sg_page(&sg_s[j++]);
+ se_mem->se_off = req->rd_offset;
+ se_mem->se_len = offset_length;
+
+ set_offset = 0;
+ get_next_table = (j > table_sg_end);
+ goto check_eot;
+ }
+
+ offset_length = (req->rd_size < req->rd_offset) ?
+ req->rd_size : req->rd_offset;
+
+ se_mem->se_page = sg_page(&sg_s[j]);
+ se_mem->se_len = offset_length;
+
+ set_offset = 1;
+
+check_eot:
+#ifdef DEBUG_RAMDISK_DR
+ printk(KERN_INFO "page: %u, size: %u, offset_length: %u, j: %u"
+ " se_mem: %p, se_page: %p se_off: %u se_len: %u\n",
+ req->rd_page, req->rd_size, offset_length, j, se_mem,
+ se_mem->se_page, se_mem->se_off, se_mem->se_len);
+#endif
+ list_add_tail(&se_mem->se_list, se_mem_list);
+ (*se_mem_cnt)++;
+
+ req->rd_size -= offset_length;
+ if (!(req->rd_size))
+ goto out;
+
+ if (!set_offset && !get_next_table)
+ continue;
+
+ if (++req->rd_page <= table->page_end_offset) {
+#ifdef DEBUG_RAMDISK_DR
+ printk(KERN_INFO "page: %u in same page table\n",
+ req->rd_page);
+#endif
+ continue;
+ }
+#ifdef DEBUG_RAMDISK_DR
+ printk(KERN_INFO "getting new page table for page: %u\n",
+ req->rd_page);
+#endif
+ table = rd_get_sg_table(dev, req->rd_page);
+ if (!(table))
+ return -1;
+
+ sg_s = &table->sg_table[j = 0];
+ }
+
+out:
+ T_TASK(task->task_se_cmd)->t_tasks_se_num += *se_mem_cnt;
+#ifdef DEBUG_RAMDISK_DR
+ printk(KERN_INFO "RD_DR - Allocated %u struct se_mem segments for task\n",
+ *se_mem_cnt);
+#endif
+ return 0;
+}
+
+/* rd_DIRECT_without_offset():
+ *
+ *
+ */
+static int rd_DIRECT_without_offset(
+ struct se_task *task,
+ struct list_head *se_mem_list,
+ u32 *se_mem_cnt,
+ u32 *task_offset)
+{
+ struct rd_request *req = RD_REQ(task);
+ struct rd_dev *dev = req->rd_dev;
+ struct rd_dev_sg_table *table;
+ struct se_mem *se_mem;
+ struct scatterlist *sg_s;
+ u32 length, j = 0;
+
+ table = rd_get_sg_table(dev, req->rd_page);
+ if (!(table))
+ return -1;
+
+ sg_s = &table->sg_table[req->rd_page - table->page_start_offset];
+#ifdef DEBUG_RAMDISK_DR
+ printk(KERN_INFO "%s DIRECT LBA: %llu, Size: %u, Page: %u\n",
+ (task->task_data_direction == DMA_TO_DEVICE) ?
+ "Write" : "Read",
+ task->task_lba, req->rd_size, req->rd_page);
+#endif
+ while (req->rd_size) {
+ se_mem = kmem_cache_zalloc(se_mem_cache, GFP_KERNEL);
+ if (!(se_mem)) {
+ printk(KERN_ERR "Unable to allocate struct se_mem\n");
+ return -1;
+ }
+ INIT_LIST_HEAD(&se_mem->se_list);
+
+ length = (req->rd_size < sg_s[j].length) ?
+ req->rd_size : sg_s[j].length;
+
+ se_mem->se_page = sg_page(&sg_s[j++]);
+ se_mem->se_len = length;
+
+#ifdef DEBUG_RAMDISK_DR
+ printk(KERN_INFO "page: %u, size: %u, j: %u se_mem: %p,"
+ " se_page: %p se_off: %u se_len: %u\n", req->rd_page,
+ req->rd_size, j, se_mem, se_mem->se_page,
+ se_mem->se_off, se_mem->se_len);
+#endif
+ list_add_tail(&se_mem->se_list, se_mem_list);
+ (*se_mem_cnt)++;
+
+ req->rd_size -= length;
+ if (!(req->rd_size))
+ goto out;
+
+ if (++req->rd_page <= table->page_end_offset) {
+#ifdef DEBUG_RAMDISK_DR
+ printk("page: %u in same page table\n",
+ req->rd_page);
+#endif
+ continue;
+ }
+#ifdef DEBUG_RAMDISK_DR
+ printk(KERN_INFO "getting new page table for page: %u\n",
+ req->rd_page);
+#endif
+ table = rd_get_sg_table(dev, req->rd_page);
+ if (!(table))
+ return -1;
+
+ sg_s = &table->sg_table[j = 0];
+ }
+
+out:
+ T_TASK(task->task_se_cmd)->t_tasks_se_num += *se_mem_cnt;
+#ifdef DEBUG_RAMDISK_DR
+ printk(KERN_INFO "RD_DR - Allocated %u struct se_mem segments for task\n",
+ *se_mem_cnt);
+#endif
+ return 0;
+}
+
+/* rd_DIRECT_do_se_mem_map():
+ *
+ *
+ */
+static int rd_DIRECT_do_se_mem_map(
+ struct se_task *task,
+ struct list_head *se_mem_list,
+ void *in_mem,
+ struct se_mem *in_se_mem,
+ struct se_mem **out_se_mem,
+ u32 *se_mem_cnt,
+ u32 *task_offset_in)
+{
+ struct se_cmd *cmd = task->task_se_cmd;
+ struct rd_request *req = RD_REQ(task);
+ u32 task_offset = *task_offset_in;
+ unsigned long long lba;
+ int ret;
+
+ req->rd_page = ((task->task_lba * DEV_ATTRIB(task->se_dev)->block_size) /
+ PAGE_SIZE);
+ lba = task->task_lba;
+ req->rd_offset = (do_div(lba,
+ (PAGE_SIZE / DEV_ATTRIB(task->se_dev)->block_size))) *
+ DEV_ATTRIB(task->se_dev)->block_size;
+ req->rd_size = task->task_size;
+
+ if (req->rd_offset)
+ ret = rd_DIRECT_with_offset(task, se_mem_list, se_mem_cnt,
+ task_offset_in);
+ else
+ ret = rd_DIRECT_without_offset(task, se_mem_list, se_mem_cnt,
+ task_offset_in);
+
+ if (ret < 0)
+ return ret;
+
+ if (CMD_TFO(cmd)->task_sg_chaining == 0)
+ return 0;
+ /*
+ * Currently prevent writers from multiple HW fabrics doing
+ * pci_map_sg() to RD_DR's internal scatterlist memory.
+ */
+ if (cmd->data_direction == DMA_TO_DEVICE) {
+ printk(KERN_ERR "DMA_TO_DEVICE not supported for"
+ " RAMDISK_DR with task_sg_chaining=1\n");
+ return -1;
+ }
+ /*
+ * Special case for if task_sg_chaining is enabled, then
+ * we setup struct se_task->task_sg[], as it will be used by
+ * transport_do_task_sg_chain() for creating chainged SGLs
+ * across multiple struct se_task->task_sg[].
+ */
+ if (!(transport_calc_sg_num(task,
+ list_entry(T_TASK(cmd)->t_mem_list->next,
+ struct se_mem, se_list),
+ task_offset)))
+ return -1;
+
+ return transport_map_mem_to_sg(task, se_mem_list, task->task_sg,
+ list_entry(T_TASK(cmd)->t_mem_list->next,
+ struct se_mem, se_list),
+ out_se_mem, se_mem_cnt, task_offset_in);
+}
+
+/* rd_DIRECT_do_task(): (Part of se_subsystem_api_t template)
+ *
+ *
+ */
+static int rd_DIRECT_do_task(struct se_task *task)
+{
+ /*
+ * At this point the locally allocated RD tables have been mapped
+ * to struct se_mem elements in rd_DIRECT_do_se_mem_map().
+ */
+ task->task_scsi_status = GOOD;
+ transport_complete_task(task, 1);
+
+ return PYX_TRANSPORT_SENT_TO_TRANSPORT;
+}
+
+/* rd_free_task(): (Part of se_subsystem_api_t template)
+ *
+ *
+ */
+static void rd_free_task(struct se_task *task)
+{
+ kfree(RD_REQ(task));
+}
+
+enum {
+ Opt_rd_pages, Opt_err
+};
+
+static match_table_t tokens = {
+ {Opt_rd_pages, "rd_pages=%d"},
+ {Opt_err, NULL}
+};
+
+static ssize_t rd_set_configfs_dev_params(
+ struct se_hba *hba,
+ struct se_subsystem_dev *se_dev,
+ const char *page,
+ ssize_t count)
+{
+ struct rd_dev *rd_dev = se_dev->se_dev_su_ptr;
+ char *orig, *ptr, *opts;
+ substring_t args[MAX_OPT_ARGS];
+ int ret = 0, arg, token;
+
+ opts = kstrdup(page, GFP_KERNEL);
+ if (!opts)
+ return -ENOMEM;
+
+ orig = opts;
+
+ while ((ptr = strsep(&opts, ",")) != NULL) {
+ if (!*ptr)
+ continue;
+
+ token = match_token(ptr, tokens, args);
+ switch (token) {
+ case Opt_rd_pages:
+ match_int(args, &arg);
+ rd_dev->rd_page_count = arg;
+ printk(KERN_INFO "RAMDISK: Referencing Page"
+ " Count: %u\n", rd_dev->rd_page_count);
+ rd_dev->rd_flags |= RDF_HAS_PAGE_COUNT;
+ break;
+ default:
+ break;
+ }
+ }
+
+ kfree(orig);
+ return (!ret) ? count : ret;
+}
+
+static ssize_t rd_check_configfs_dev_params(struct se_hba *hba, struct se_subsystem_dev *se_dev)
+{
+ struct rd_dev *rd_dev = se_dev->se_dev_su_ptr;
+
+ if (!(rd_dev->rd_flags & RDF_HAS_PAGE_COUNT)) {
+ printk(KERN_INFO "Missing rd_pages= parameter\n");
+ return -1;
+ }
+
+ return 0;
+}
+
+static ssize_t rd_show_configfs_dev_params(
+ struct se_hba *hba,
+ struct se_subsystem_dev *se_dev,
+ char *b)
+{
+ struct rd_dev *rd_dev = se_dev->se_dev_su_ptr;
+ ssize_t bl = sprintf(b, "TCM RamDisk ID: %u RamDisk Makeup: %s\n",
+ rd_dev->rd_dev_id, (rd_dev->rd_direct) ?
+ "rd_direct" : "rd_mcp");
+ bl += sprintf(b + bl, " PAGES/PAGE_SIZE: %u*%lu"
+ " SG_table_count: %u\n", rd_dev->rd_page_count,
+ PAGE_SIZE, rd_dev->sg_table_count);
+ return bl;
+}
+
+/* rd_get_cdb(): (Part of se_subsystem_api_t template)
+ *
+ *
+ */
+static unsigned char *rd_get_cdb(struct se_task *task)
+{
+ struct rd_request *req = RD_REQ(task);
+
+ return req->rd_scsi_cdb;
+}
+
+static u32 rd_get_device_rev(struct se_device *dev)
+{
+ return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
+}
+
+static u32 rd_get_device_type(struct se_device *dev)
+{
+ return TYPE_DISK;
+}
+
+static sector_t rd_get_blocks(struct se_device *dev)
+{
+ struct rd_dev *rd_dev = dev->dev_ptr;
+ unsigned long long blocks_long = ((rd_dev->rd_page_count * PAGE_SIZE) /
+ DEV_ATTRIB(dev)->block_size) - 1;
+
+ return blocks_long;
+}
+
+static struct se_subsystem_api rd_dr_template = {
+ .name = "rd_dr",
+ .transport_type = TRANSPORT_PLUGIN_VHBA_VDEV,
+ .attach_hba = rd_attach_hba,
+ .detach_hba = rd_detach_hba,
+ .allocate_virtdevice = rd_DIRECT_allocate_virtdevice,
+ .create_virtdevice = rd_DIRECT_create_virtdevice,
+ .free_device = rd_free_device,
+ .alloc_task = rd_alloc_task,
+ .do_task = rd_DIRECT_do_task,
+ .free_task = rd_free_task,
+ .check_configfs_dev_params = rd_check_configfs_dev_params,
+ .set_configfs_dev_params = rd_set_configfs_dev_params,
+ .show_configfs_dev_params = rd_show_configfs_dev_params,
+ .get_cdb = rd_get_cdb,
+ .get_device_rev = rd_get_device_rev,
+ .get_device_type = rd_get_device_type,
+ .get_blocks = rd_get_blocks,
+ .do_se_mem_map = rd_DIRECT_do_se_mem_map,
+};
+
+static struct se_subsystem_api rd_mcp_template = {
+ .name = "rd_mcp",
+ .transport_type = TRANSPORT_PLUGIN_VHBA_VDEV,
+ .attach_hba = rd_attach_hba,
+ .detach_hba = rd_detach_hba,
+ .allocate_virtdevice = rd_MEMCPY_allocate_virtdevice,
+ .create_virtdevice = rd_MEMCPY_create_virtdevice,
+ .free_device = rd_free_device,
+ .alloc_task = rd_alloc_task,
+ .do_task = rd_MEMCPY_do_task,
+ .free_task = rd_free_task,
+ .check_configfs_dev_params = rd_check_configfs_dev_params,
+ .set_configfs_dev_params = rd_set_configfs_dev_params,
+ .show_configfs_dev_params = rd_show_configfs_dev_params,
+ .get_cdb = rd_get_cdb,
+ .get_device_rev = rd_get_device_rev,
+ .get_device_type = rd_get_device_type,
+ .get_blocks = rd_get_blocks,
+};
+
+int __init rd_module_init(void)
+{
+ int ret;
+
+ ret = transport_subsystem_register(&rd_dr_template);
+ if (ret < 0)
+ return ret;
+
+ ret = transport_subsystem_register(&rd_mcp_template);
+ if (ret < 0) {
+ transport_subsystem_release(&rd_dr_template);
+ return ret;
+ }
+
+ return 0;
+}
+
+void rd_module_exit(void)
+{
+ transport_subsystem_release(&rd_dr_template);
+ transport_subsystem_release(&rd_mcp_template);
+}
diff --git a/drivers/target/target_core_rd.h b/drivers/target/target_core_rd.h
new file mode 100644
index 0000000..13badfb
--- /dev/null
+++ b/drivers/target/target_core_rd.h
@@ -0,0 +1,73 @@
+#ifndef TARGET_CORE_RD_H
+#define TARGET_CORE_RD_H
+
+#define RD_HBA_VERSION "v4.0"
+#define RD_DR_VERSION "4.0"
+#define RD_MCP_VERSION "4.0"
+
+/* Largest piece of memory kmalloc can allocate */
+#define RD_MAX_ALLOCATION_SIZE 65536
+/* Maximum queuedepth for the Ramdisk HBA */
+#define RD_HBA_QUEUE_DEPTH 256
+#define RD_DEVICE_QUEUE_DEPTH 32
+#define RD_MAX_DEVICE_QUEUE_DEPTH 128
+#define RD_BLOCKSIZE 512
+#define RD_MAX_SECTORS 1024
+
+extern struct kmem_cache *se_mem_cache;
+
+/* Used in target_core_init_configfs() for virtual LUN 0 access */
+int __init rd_module_init(void);
+void rd_module_exit(void);
+
+#define RRF_EMULATE_CDB 0x01
+#define RRF_GOT_LBA 0x02
+
+struct rd_request {
+ struct se_task rd_task;
+
+ /* SCSI CDB from iSCSI Command PDU */
+ unsigned char rd_scsi_cdb[TCM_MAX_COMMAND_SIZE];
+ /* Offset from start of page */
+ u32 rd_offset;
+ /* Starting page in Ramdisk for request */
+ u32 rd_page;
+ /* Total number of pages needed for request */
+ u32 rd_page_count;
+ /* Scatterlist count */
+ u32 rd_size;
+ /* Ramdisk device */
+ struct rd_dev *rd_dev;
+} ____cacheline_aligned;
+
+struct rd_dev_sg_table {
+ u32 page_start_offset;
+ u32 page_end_offset;
+ u32 rd_sg_count;
+ struct scatterlist *sg_table;
+} ____cacheline_aligned;
+
+#define RDF_HAS_PAGE_COUNT 0x01
+
+struct rd_dev {
+ int rd_direct;
+ u32 rd_flags;
+ /* Unique Ramdisk Device ID in Ramdisk HBA */
+ u32 rd_dev_id;
+ /* Total page count for ramdisk device */
+ u32 rd_page_count;
+ /* Number of SG tables in sg_table_array */
+ u32 sg_table_count;
+ u32 rd_queue_depth;
+ /* Array of rd_dev_sg_table_t containing scatterlists */
+ struct rd_dev_sg_table *sg_table_array;
+ /* Ramdisk HBA device is connected to */
+ struct rd_host *rd_host;
+} ____cacheline_aligned;
+
+struct rd_host {
+ u32 rd_host_dev_id_count;
+ u32 rd_host_id; /* Unique Ramdisk Host ID */
+} ____cacheline_aligned;
+
+#endif /* TARGET_CORE_RD_H */
--
1.7.3.4
--
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