dirty fix to merging

1 files changed, 662 insertions, 0 deletions

diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c
new file mode 100644
index 00000000..f2869553
--- /dev/null
+++ b/drivers/target/target_core_file.c
@@ -0,0 +1,662 @@
+/*******************************************************************************
+ * Filename:  target_core_file.c
+ *
+ * This file contains the Storage Engine <-> FILEIO transport specific functions
+ *
+ * Copyright (c) 2005 PyX Technologies, Inc.
+ * Copyright (c) 2005-2006 SBE, Inc.  All Rights Reserved.
+ * Copyright (c) 2007-2010 Rising Tide Systems
+ * Copyright (c) 2008-2010 Linux-iSCSI.org
+ *
+ * Nicholas A. Bellinger <nab@kernel.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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ ******************************************************************************/
+
+#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/module.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_host.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_backend.h>
+
+#include "target_core_file.h"
+
+static struct se_subsystem_api fileio_template;
+
+/*	fd_attach_hba(): (Part of se_subsystem_api_t template)
+ *
+ *
+ */
+static int fd_attach_hba(struct se_hba *hba, u32 host_id)
+{
+	struct fd_host *fd_host;
+
+	fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
+	if (!fd_host) {
+		pr_err("Unable to allocate memory for struct fd_host\n");
+		return -ENOMEM;
+	}
+
+	fd_host->fd_host_id = host_id;
+
+	hba->hba_ptr = fd_host;
+
+	pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
+		" Target Core Stack %s\n", hba->hba_id, FD_VERSION,
+		TARGET_CORE_MOD_VERSION);
+	pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic"
+		" MaxSectors: %u\n",
+		hba->hba_id, fd_host->fd_host_id, FD_MAX_SECTORS);
+
+	return 0;
+}
+
+static void fd_detach_hba(struct se_hba *hba)
+{
+	struct fd_host *fd_host = hba->hba_ptr;
+
+	pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
+		" Target Core\n", hba->hba_id, fd_host->fd_host_id);
+
+	kfree(fd_host);
+	hba->hba_ptr = NULL;
+}
+
+static void *fd_allocate_virtdevice(struct se_hba *hba, const char *name)
+{
+	struct fd_dev *fd_dev;
+	struct fd_host *fd_host = hba->hba_ptr;
+
+	fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL);
+	if (!fd_dev) {
+		pr_err("Unable to allocate memory for struct fd_dev\n");
+		return NULL;
+	}
+
+	fd_dev->fd_host = fd_host;
+
+	pr_debug("FILEIO: Allocated fd_dev for %p\n", name);
+
+	return fd_dev;
+}
+
+/*	fd_create_virtdevice(): (Part of se_subsystem_api_t template)
+ *
+ *
+ */
+static struct se_device *fd_create_virtdevice(
+	struct se_hba *hba,
+	struct se_subsystem_dev *se_dev,
+	void *p)
+{
+	char *dev_p = NULL;
+	struct se_device *dev;
+	struct se_dev_limits dev_limits;
+	struct queue_limits *limits;
+	struct fd_dev *fd_dev = p;
+	struct fd_host *fd_host = hba->hba_ptr;
+	mm_segment_t old_fs;
+	struct file *file;
+	struct inode *inode = NULL;
+	int dev_flags = 0, flags, ret = -EINVAL;
+
+	memset(&dev_limits, 0, sizeof(struct se_dev_limits));
+
+	old_fs = get_fs();
+	set_fs(get_ds());
+	dev_p = getname(fd_dev->fd_dev_name);
+	set_fs(old_fs);
+
+	if (IS_ERR(dev_p)) {
+		pr_err("getname(%s) failed: %lu\n",
+			fd_dev->fd_dev_name, IS_ERR(dev_p));
+		ret = PTR_ERR(dev_p);
+		goto fail;
+	}
+#if 0
+	if (di->no_create_file)
+		flags = O_RDWR | O_LARGEFILE;
+	else
+		flags = O_RDWR | O_CREAT | O_LARGEFILE;
+#else
+	flags = O_RDWR | O_CREAT | O_LARGEFILE;
+#endif
+/*	flags |= O_DIRECT; */
+	/*
+	 * If fd_buffered_io=1 has not been set explicitly (the default),
+	 * use O_SYNC to force FILEIO writes to disk.
+	 */
+	if (!(fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO))
+		flags |= O_SYNC;
+
+	file = filp_open(dev_p, flags, 0600);
+	if (IS_ERR(file)) {
+		pr_err("filp_open(%s) failed\n", dev_p);
+		ret = PTR_ERR(file);
+		goto fail;
+	}
+	if (!file || !file->f_dentry) {
+		pr_err("filp_open(%s) failed\n", dev_p);
+		goto fail;
+	}
+	fd_dev->fd_file = file;
+	/*
+	 * If using a block backend with this struct file, we extract
+	 * fd_dev->fd_[block,dev]_size from struct block_device.
+	 *
+	 * Otherwise, we use the passed fd_size= from configfs
+	 */
+	inode = file->f_mapping->host;
+	if (S_ISBLK(inode->i_mode)) {
+		struct request_queue *q;
+		unsigned long long dev_size;
+		/*
+		 * Setup the local scope queue_limits from struct request_queue->limits
+		 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
+		 */
+		q = bdev_get_queue(inode->i_bdev);
+		limits = &dev_limits.limits;
+		limits->logical_block_size = bdev_logical_block_size(inode->i_bdev);
+		limits->max_hw_sectors = queue_max_hw_sectors(q);
+		limits->max_sectors = queue_max_sectors(q);
+		/*
+		 * Determine the number of bytes from i_size_read() minus
+		 * one (1) logical sector from underlying struct block_device
+		 */
+		fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev);
+		dev_size = (i_size_read(file->f_mapping->host) -
+				       fd_dev->fd_block_size);
+
+		pr_debug("FILEIO: Using size: %llu bytes from struct"
+			" block_device blocks: %llu logical_block_size: %d\n",
+			dev_size, div_u64(dev_size, fd_dev->fd_block_size),
+			fd_dev->fd_block_size);
+	} else {
+		if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
+			pr_err("FILEIO: Missing fd_dev_size="
+				" parameter, and no backing struct"
+				" block_device\n");
+			goto fail;
+		}
+
+		limits = &dev_limits.limits;
+		limits->logical_block_size = FD_BLOCKSIZE;
+		limits->max_hw_sectors = FD_MAX_SECTORS;
+		limits->max_sectors = FD_MAX_SECTORS;
+		fd_dev->fd_block_size = FD_BLOCKSIZE;
+	}
+
+	dev_limits.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
+	dev_limits.queue_depth = FD_DEVICE_QUEUE_DEPTH;
+
+	dev = transport_add_device_to_core_hba(hba, &fileio_template,
+				se_dev, dev_flags, fd_dev,
+				&dev_limits, "FILEIO", FD_VERSION);
+	if (!dev)
+		goto fail;
+
+	fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
+	fd_dev->fd_queue_depth = dev->queue_depth;
+
+	pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
+		" %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
+			fd_dev->fd_dev_name, fd_dev->fd_dev_size);
+
+	putname(dev_p);
+	return dev;
+fail:
+	if (fd_dev->fd_file) {
+		filp_close(fd_dev->fd_file, NULL);
+		fd_dev->fd_file = NULL;
+	}
+	putname(dev_p);
+	return ERR_PTR(ret);
+}
+
+/*	fd_free_device(): (Part of se_subsystem_api_t template)
+ *
+ *
+ */
+static void fd_free_device(void *p)
+{
+	struct fd_dev *fd_dev = p;
+
+	if (fd_dev->fd_file) {
+		filp_close(fd_dev->fd_file, NULL);
+		fd_dev->fd_file = NULL;
+	}
+
+	kfree(fd_dev);
+}
+
+static inline struct fd_request *FILE_REQ(struct se_task *task)
+{
+	return container_of(task, struct fd_request, fd_task);
+}
+
+
+static struct se_task *
+fd_alloc_task(unsigned char *cdb)
+{
+	struct fd_request *fd_req;
+
+	fd_req = kzalloc(sizeof(struct fd_request), GFP_KERNEL);
+	if (!fd_req) {
+		pr_err("Unable to allocate struct fd_request\n");
+		return NULL;
+	}
+
+	return &fd_req->fd_task;
+}
+
+static int fd_do_readv(struct se_task *task)
+{
+	struct fd_request *req = FILE_REQ(task);
+	struct se_device *se_dev = req->fd_task.task_se_cmd->se_dev;
+	struct fd_dev *dev = se_dev->dev_ptr;
+	struct file *fd = dev->fd_file;
+	struct scatterlist *sg = task->task_sg;
+	struct iovec *iov;
+	mm_segment_t old_fs;
+	loff_t pos = (task->task_lba *
+		      se_dev->se_sub_dev->se_dev_attrib.block_size);
+	int ret = 0, i;
+
+	iov = kzalloc(sizeof(struct iovec) * task->task_sg_nents, GFP_KERNEL);
+	if (!iov) {
+		pr_err("Unable to allocate fd_do_readv iov[]\n");
+		return -ENOMEM;
+	}
+
+	for_each_sg(task->task_sg, sg, task->task_sg_nents, i) {
+		iov[i].iov_len = sg->length;
+		iov[i].iov_base = sg_virt(sg);
+	}
+
+	old_fs = get_fs();
+	set_fs(get_ds());
+	ret = vfs_readv(fd, &iov[0], task->task_sg_nents, &pos);
+	set_fs(old_fs);
+
+	kfree(iov);
+	/*
+	 * Return zeros and GOOD status even if the READ did not return
+	 * the expected virt_size for struct file w/o a backing struct
+	 * block_device.
+	 */
+	if (S_ISBLK(fd->f_dentry->d_inode->i_mode)) {
+		if (ret < 0 || ret != task->task_size) {
+			pr_err("vfs_readv() returned %d,"
+				" expecting %d for S_ISBLK\n", ret,
+				(int)task->task_size);
+			return (ret < 0 ? ret : -EINVAL);
+		}
+	} else {
+		if (ret < 0) {
+			pr_err("vfs_readv() returned %d for non"
+				" S_ISBLK\n", ret);
+			return ret;
+		}
+	}
+
+	return 1;
+}
+
+static int fd_do_writev(struct se_task *task)
+{
+	struct fd_request *req = FILE_REQ(task);
+	struct se_device *se_dev = req->fd_task.task_se_cmd->se_dev;
+	struct fd_dev *dev = se_dev->dev_ptr;
+	struct file *fd = dev->fd_file;
+	struct scatterlist *sg = task->task_sg;
+	struct iovec *iov;
+	mm_segment_t old_fs;
+	loff_t pos = (task->task_lba *
+		      se_dev->se_sub_dev->se_dev_attrib.block_size);
+	int ret, i = 0;
+
+	iov = kzalloc(sizeof(struct iovec) * task->task_sg_nents, GFP_KERNEL);
+	if (!iov) {
+		pr_err("Unable to allocate fd_do_writev iov[]\n");
+		return -ENOMEM;
+	}
+
+	for_each_sg(task->task_sg, sg, task->task_sg_nents, i) {
+		iov[i].iov_len = sg->length;
+		iov[i].iov_base = sg_virt(sg);
+	}
+
+	old_fs = get_fs();
+	set_fs(get_ds());
+	ret = vfs_writev(fd, &iov[0], task->task_sg_nents, &pos);
+	set_fs(old_fs);
+
+	kfree(iov);
+
+	if (ret < 0 || ret != task->task_size) {
+		pr_err("vfs_writev() returned %d\n", ret);
+		return (ret < 0 ? ret : -EINVAL);
+	}
+
+	return 1;
+}
+
+static void fd_emulate_sync_cache(struct se_task *task)
+{
+	struct se_cmd *cmd = task->task_se_cmd;
+	struct se_device *dev = cmd->se_dev;
+	struct fd_dev *fd_dev = dev->dev_ptr;
+	int immed = (cmd->t_task_cdb[1] & 0x2);
+	loff_t start, end;
+	int ret;
+
+	/*
+	 * If the Immediate bit is set, queue up the GOOD response
+	 * for this SYNCHRONIZE_CACHE op
+	 */
+	if (immed)
+		transport_complete_sync_cache(cmd, 1);
+
+	/*
+	 * Determine if we will be flushing the entire device.
+	 */
+	if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
+		start = 0;
+		end = LLONG_MAX;
+	} else {
+		start = cmd->t_task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
+		if (cmd->data_length)
+			end = start + cmd->data_length;
+		else
+			end = LLONG_MAX;
+	}
+
+	ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
+	if (ret != 0)
+		pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
+
+	if (!immed)
+		transport_complete_sync_cache(cmd, ret == 0);
+}
+
+/*
+ * WRITE Force Unit Access (FUA) emulation on a per struct se_task
+ * LBA range basis..
+ */
+static void fd_emulate_write_fua(struct se_cmd *cmd, struct se_task *task)
+{
+	struct se_device *dev = cmd->se_dev;
+	struct fd_dev *fd_dev = dev->dev_ptr;
+	loff_t start = task->task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
+	loff_t end = start + task->task_size;
+	int ret;
+
+	pr_debug("FILEIO: FUA WRITE LBA: %llu, bytes: %u\n",
+			task->task_lba, task->task_size);
+
+	ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
+	if (ret != 0)
+		pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
+}
+
+static int fd_do_task(struct se_task *task)
+{
+	struct se_cmd *cmd = task->task_se_cmd;
+	struct se_device *dev = cmd->se_dev;
+	int ret = 0;
+
+	/*
+	 * Call vectorized fileio functions to map struct scatterlist
+	 * physical memory addresses to struct iovec virtual memory.
+	 */
+	if (task->task_data_direction == DMA_FROM_DEVICE) {
+		ret = fd_do_readv(task);
+	} else {
+		ret = fd_do_writev(task);
+
+		if (ret > 0 &&
+		    dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0 &&
+		    dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
+		    (cmd->se_cmd_flags & SCF_FUA)) {
+			/*
+			 * We might need to be a bit smarter here
+			 * and return some sense data to let the initiator
+			 * know the FUA WRITE cache sync failed..?
+			 */
+			fd_emulate_write_fua(cmd, task);
+		}
+
+	}
+
+	if (ret < 0) {
+		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+		return ret;
+	}
+	if (ret) {
+		task->task_scsi_status = GOOD;
+		transport_complete_task(task, 1);
+	}
+	return 0;
+}
+
+/*	fd_free_task(): (Part of se_subsystem_api_t template)
+ *
+ *
+ */
+static void fd_free_task(struct se_task *task)
+{
+	struct fd_request *req = FILE_REQ(task);
+
+	kfree(req);
+}
+
+enum {
+	Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
+};
+
+static match_table_t tokens = {
+	{Opt_fd_dev_name, "fd_dev_name=%s"},
+	{Opt_fd_dev_size, "fd_dev_size=%s"},
+	{Opt_fd_buffered_io, "fd_buffered_io=%d"},
+	{Opt_err, NULL}
+};
+
+static ssize_t fd_set_configfs_dev_params(
+	struct se_hba *hba,
+	struct se_subsystem_dev *se_dev,
+	const char *page, ssize_t count)
+{
+	struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
+	char *orig, *ptr, *arg_p, *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, ",\n")) != NULL) {
+		if (!*ptr)
+			continue;
+
+		token = match_token(ptr, tokens, args);
+		switch (token) {
+		case Opt_fd_dev_name:
+			arg_p = match_strdup(&args[0]);
+			if (!arg_p) {
+				ret = -ENOMEM;
+				break;
+			}
+			snprintf(fd_dev->fd_dev_name, FD_MAX_DEV_NAME,
+					"%s", arg_p);
+			kfree(arg_p);
+			pr_debug("FILEIO: Referencing Path: %s\n",
+					fd_dev->fd_dev_name);
+			fd_dev->fbd_flags |= FBDF_HAS_PATH;
+			break;
+		case Opt_fd_dev_size:
+			arg_p = match_strdup(&args[0]);
+			if (!arg_p) {
+				ret = -ENOMEM;
+				break;
+			}
+			ret = strict_strtoull(arg_p, 0, &fd_dev->fd_dev_size);
+			kfree(arg_p);
+			if (ret < 0) {
+				pr_err("strict_strtoull() failed for"
+						" fd_dev_size=\n");
+				goto out;
+			}
+			pr_debug("FILEIO: Referencing Size: %llu"
+					" bytes\n", fd_dev->fd_dev_size);
+			fd_dev->fbd_flags |= FBDF_HAS_SIZE;
+			break;
+		case Opt_fd_buffered_io:
+			match_int(args, &arg);
+			if (arg != 1) {
+				pr_err("bogus fd_buffered_io=%d value\n", arg);
+				ret = -EINVAL;
+				goto out;
+			}
+
+			pr_debug("FILEIO: Using buffered I/O"
+				" operations for struct fd_dev\n");
+
+			fd_dev->fbd_flags |= FDBD_USE_BUFFERED_IO;
+			break;
+		default:
+			break;
+		}
+	}
+
+out:
+	kfree(orig);
+	return (!ret) ? count : ret;
+}
+
+static ssize_t fd_check_configfs_dev_params(struct se_hba *hba, struct se_subsystem_dev *se_dev)
+{
+	struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
+
+	if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
+		pr_err("Missing fd_dev_name=\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static ssize_t fd_show_configfs_dev_params(
+	struct se_hba *hba,
+	struct se_subsystem_dev *se_dev,
+	char *b)
+{
+	struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
+	ssize_t bl = 0;
+
+	bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
+	bl += sprintf(b + bl, "        File: %s  Size: %llu  Mode: %s\n",
+		fd_dev->fd_dev_name, fd_dev->fd_dev_size,
+		(fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO) ?
+		"Buffered" : "Synchronous");
+	return bl;
+}
+
+/*	fd_get_device_rev(): (Part of se_subsystem_api_t template)
+ *
+ *
+ */
+static u32 fd_get_device_rev(struct se_device *dev)
+{
+	return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
+}
+
+/*	fd_get_device_type(): (Part of se_subsystem_api_t template)
+ *
+ *
+ */
+static u32 fd_get_device_type(struct se_device *dev)
+{
+	return TYPE_DISK;
+}
+
+static sector_t fd_get_blocks(struct se_device *dev)
+{
+	struct fd_dev *fd_dev = dev->dev_ptr;
+	struct file *f = fd_dev->fd_file;
+	struct inode *i = f->f_mapping->host;
+	unsigned long long dev_size;
+	/*
+	 * When using a file that references an underlying struct block_device,
+	 * ensure dev_size is always based on the current inode size in order
+	 * to handle underlying block_device resize operations.
+	 */
+	if (S_ISBLK(i->i_mode))
+		dev_size = (i_size_read(i) - fd_dev->fd_block_size);
+	else
+		dev_size = fd_dev->fd_dev_size;
+
+	return div_u64(dev_size, dev->se_sub_dev->se_dev_attrib.block_size);
+}
+
+static struct se_subsystem_api fileio_template = {
+	.name			= "fileio",
+	.owner			= THIS_MODULE,
+	.transport_type		= TRANSPORT_PLUGIN_VHBA_PDEV,
+	.write_cache_emulated	= 1,
+	.fua_write_emulated	= 1,
+	.attach_hba		= fd_attach_hba,
+	.detach_hba		= fd_detach_hba,
+	.allocate_virtdevice	= fd_allocate_virtdevice,
+	.create_virtdevice	= fd_create_virtdevice,
+	.free_device		= fd_free_device,
+	.alloc_task		= fd_alloc_task,
+	.do_task		= fd_do_task,
+	.do_sync_cache		= fd_emulate_sync_cache,
+	.free_task		= fd_free_task,
+	.check_configfs_dev_params = fd_check_configfs_dev_params,
+	.set_configfs_dev_params = fd_set_configfs_dev_params,
+	.show_configfs_dev_params = fd_show_configfs_dev_params,
+	.get_device_rev		= fd_get_device_rev,
+	.get_device_type	= fd_get_device_type,
+	.get_blocks		= fd_get_blocks,
+};
+
+static int __init fileio_module_init(void)
+{
+	return transport_subsystem_register(&fileio_template);
+}
+
+static void fileio_module_exit(void)
+{
+	transport_subsystem_release(&fileio_template);
+}
+
+MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
+MODULE_AUTHOR("nab@Linux-iSCSI.org");
+MODULE_LICENSE("GPL");
+
+module_init(fileio_module_init);
+module_exit(fileio_module_exit);