/*******************************************************************************
* Filename: target_core_file.c
*
* This file contains the Storage Engine <-> FILEIO transport specific functions
*
* (c) Copyright 2005-2013 Datera, Inc.
*
* 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 <linux/falloc.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <asm/unaligned.h>
#include <target/target_core_base.h>
#include <target/target_core_backend.h>
#include <target/target_core_backend_configfs.h>
#include "target_core_file.h"
static inline struct fd_dev *FD_DEV(struct se_device *dev)
{
return container_of(dev, struct fd_dev, dev);
}
/* 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\n",
hba->hba_id, fd_host->fd_host_id);
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 struct se_device *fd_alloc_device(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->dev;
}
static int fd_configure_device(struct se_device *dev)
{
struct fd_dev *fd_dev = FD_DEV(dev);
struct fd_host *fd_host = dev->se_hba->hba_ptr;
struct file *file;
struct inode *inode = NULL;
int flags, ret = -EINVAL;
if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
pr_err("Missing fd_dev_name=\n");
return -EINVAL;
}
/*
* Use O_DSYNC by default instead of O_SYNC to forgo syncing
* of pure timestamp updates.
*/
flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
/*
* Optionally allow fd_buffered_io=1 to be enabled for people
* who want use the fs buffer cache as an WriteCache mechanism.
*
* This means that in event of a hard failure, there is a risk
* of silent data-loss if the SCSI client has *not* performed a
* forced unit access (FUA) write, or issued SYNCHRONIZE_CACHE
* to write-out the entire device cache.
*/
if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
pr_debug("FILEIO: Disabling O_DSYNC, using buffered FILEIO\n");
flags &= ~O_DSYNC;
}
file = filp_open(fd_dev->fd_dev_name, flags, 0600);
if (IS_ERR(file)) {
pr_err("filp_open(%s) failed\n", fd_dev->fd_dev_name);
ret = PTR_ERR(file);
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 = bdev_get_queue(inode->i_bdev);
unsigned long long dev_size;
fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev);
/*
* Determine the number of bytes from i_size_read() minus
* one (1) logical sector from underlying struct block_device
*/
dev_size = (i_size_read