path: root/drivers/target/target_core_iblock.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*******************************************************************************
 * Filename:  target_core_iblock.c
 *
 * This file contains the Storage Engine  <-> Linux BlockIO transport
 * specific functions.
 *
 * (c) Copyright 2003-2013 Datera, Inc.
 *
 * Nicholas A. Bellinger <nab@kernel.org>
 *
 ******************************************************************************/

#include <linux/string.h>
#include <linux/parser.h>
#include <linux/timer.h>
#include <linux/fs.h>
#include <linux/blkdev.h>
#include <linux/blk-integrity.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/bio.h>
#include <linux/file.h>
#include <linux/module.h>
#include <linux/scatterlist.h>
#include <linux/pr.h>
#include <scsi/scsi_proto.h>
#include <scsi/scsi_common.h>
#include <asm/unaligned.h>

#include <target/target_core_base.h>
#include <target/target_core_backend.h>

#include "target_core_iblock.h"
#include "target_core_pr.h"

#define IBLOCK_MAX_BIO_PER_TASK	 32	/* max # of bios to submit at a time */
#define IBLOCK_BIO_POOL_SIZE	128

static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev)
{
	return container_of(dev, struct iblock_dev, dev);
}


static int iblock_attach_hba(struct se_hba *hba, u32 host_id)
{
	pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on"
		" Generic Target Core Stack %s\n", hba->hba_id,
		IBLOCK_VERSION, TARGET_CORE_VERSION);
	return 0;
}

static void iblock_detach_hba(struct se_hba *hba)
{
}

static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *name)
{
	struct iblock_dev *ib_dev = NULL;

	ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL);
	if (!ib_dev) {
		pr_err("Unable to allocate struct iblock_dev\n");
		return NULL;
	}

	ib_dev->ibd_plug = kcalloc(nr_cpu_ids, sizeof(*ib_dev->ibd_plug),
				   GFP_KERNEL);
	if (!ib_dev->ibd_plug)
		goto free_dev;

	pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);

	return &ib_dev->dev;

free_dev:
	kfree(ib_dev);
	return NULL;
}

static bool iblock_configure_unmap(struct se_device *dev)
{
	struct iblock_dev *ib_dev = IBLOCK_DEV(dev);

	return target_configure_unmap_from_queue(&dev->dev_attrib,
						 ib_dev->ibd_bd);
}

static int iblock_configure_device(struct se_device *dev)
{
	struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
	struct request_queue *q;
	struct bdev_handle *bdev_handle;
	struct block_device *bd;
	struct blk_integrity *bi;
	blk_mode_t mode = BLK_OPEN_READ;
	unsigned int max_write_zeroes_sectors;
	int ret;

	if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) {
		pr_err("Missing udev_path= parameters for IBLOCK\n");
		return -EINVAL;
	}

	ret = bioset_init(&ib_dev->ibd_bio_set, IBLOCK_BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
	if (ret) {
		pr_err("IBLOCK: Unable to create bioset\n");
		goto out;
	}

	pr_debug( "IBLOCK: Claiming struct block_device: %s\n",
			ib_dev->ibd_udev_path);

	if (!ib_dev->ibd_readonly)
		mode |= BLK_OPEN_WRITE;
	else
		dev->dev_flags |= DF_READ_ONLY;

	bdev_handle = bdev_open_by_path(ib_dev->ibd_udev_path, mode, ib_dev,
					NULL);
	if (IS_ERR(bdev_handle)) {
		ret = PTR_ERR(bdev_handle);
		goto out_free_bioset;
	}
	ib_dev->ibd_bdev_handle = bdev_handle;
	ib_dev->ibd_bd = bd = bdev_handle->bdev;

	q = bdev_get_queue(bd);

	dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd);
	dev->dev_attrib.hw_max_sectors = mult_frac(queue_max_hw_sectors(q),
			SECTOR_SIZE,
			dev->dev_attrib.hw_block_size);