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The LITMUS^RT kernel.

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author	Harvey Harrison <harvey.harrison@gmail.com>	2009-01-07 15:19:31 -0500
committer	Linus Torvalds <torvalds@linux-foundation.org>	2009-01-07 15:22:04 -0500
commit	8903709b054a8dafe4e8c6d9a6444034d7aba36f (patch)
tree	dac4ab43946fbdc2f0c104a9be5c5685098b9543 /fs/proc/root.c
parent	daf4b805c1711f730d42a5dfc5a65ee05b3c9ecf (diff)

xtensa: introduce swab.h

Fixes compile breakage as linux/byteorder.h was removed. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Diffstat (limited to 'fs/proc/root.c')

0 files changed, 0 insertions, 0 deletions

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/*******************************************************************************
 * Filename:  target_core_file.c
 *
 * This file contains the Storage Engine <-> FILEIO transport specific functions
 *
 * (c) Copyright 2005-2012 RisingTide Systems LLC.
 *
 * 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_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"
		" 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 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(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);
		/*
		 * Check if the underlying struct block_device request_queue supports
		 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
		 * in ATA and we need to set TPE=1
		 */
		if (blk_queue_discard(q)) {
			dev->dev_attrib.max_unmap_lba_count =
				q->limits.max_discard_sectors;
			/*
			 * Currently hardcoded to 1 in Linux/SCSI code..
			 */
			dev->dev_attrib.max_unmap_block_desc_count = 1;
			dev->dev_attrib.unmap_granularity =
				q->limits.discard_granularity >> 9;
			dev->dev_attrib.unmap_granularity_alignment =
				q->limits.discard_alignment;
			pr_debug("IFILE: BLOCK Discard support available,"
					" disabled by default\n");
		}
		/*
		 * Enable write same emulation for IBLOCK and use 0xFFFF as
		 * the smaller WRITE_SAME(10) only has a two-byte block count.
		 */
		dev->dev_attrib.max_write_same_len = 0xFFFF;

		if (blk_queue_nonrot(q))
			dev->dev_attrib.is_nonrot = 1;
	} 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;
		}

		fd_dev->fd_block_size = FD_BLOCKSIZE;
		/*
		 * Limit UNMAP emulation to 8k Number of LBAs (NoLB)
		 */
		dev->dev_attrib.max_unmap_lba_count = 0x2000;
		/*
		 * Currently hardcoded to 1 in Linux/SCSI code..
		 */
		dev->dev_attrib.max_unmap_block_desc_count = 1;
		dev->dev_attrib.unmap_granularity = 1;
		dev->dev_attrib.unmap_granularity_alignment = 0;

		/*
		 * Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB)
		 * based upon struct iovec limit for vfs_writev()
		 */
		dev->dev_attrib.max_write_same_len = 0x1000;
	}

	dev->dev_attrib.hw_block_size = fd_dev->fd_block_size;
	dev->dev_attrib.hw_max_sectors = FD_MAX_SECTORS;
	dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;

	if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
		pr_debug("FILEIO: Forcing setting of emulate_write_cache=1"
			" with FDBD_HAS_BUFFERED_IO_WCE\n");
		dev->dev_attrib.emulate_write_cache = 1;
	}

	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);

	return 0;
fail:
	if (fd_dev->fd_file) {
		filp_close(fd_dev->fd_file, NULL);
		fd_dev->fd_file = NULL;
	}
	return ret;
}

static void fd_free_device(struct se_device *dev)
{
	struct fd_dev *fd_dev = FD_DEV(dev);

	if (fd_dev->fd_file) {
		filp_close(fd_dev->fd_file, NULL);
		fd_dev->fd_file = NULL;
	}

	kfree(fd_dev);
}

static int fd_do_rw(struct se_cmd *cmd, struct scatterlist *sgl,
		u32 sgl_nents, int is_write)
{
	struct se_device *se_dev = cmd->se_dev;
	struct fd_dev *dev = FD_DEV(se_dev);
	struct file *fd = dev->fd_file;
	struct scatterlist *sg;
	struct iovec *iov;
	mm_segment_t old_fs;
	loff_t pos = (cmd->t_task_lba * se_dev->dev_attrib.block_size);
	int ret = 0, i;

	iov = kzalloc(sizeof(struct iovec) * sgl_nents, GFP_KERNEL);
	if (!iov) {
		pr_err("Unable to allocate fd_do_readv iov[]\n");
		return -ENOMEM;
	}

	for_each_sg(sgl, sg, sgl_nents, i) {
		iov[i].iov_len = sg->length;
		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset;
	}

	old_fs = get_fs();
	set_fs(get_ds());

	if (is_write)
		ret = vfs_writev(fd, &iov[0], sgl_nents, &pos);
	else
		ret = vfs_readv(fd, &iov[0], sgl_nents, &pos);

	set_fs(old_fs);

	for_each_sg(sgl, sg, sgl_nents, i)
		kunmap(sg_page(sg));

	kfree(iov);

	if (is_write) {
		if (ret < 0 || ret != cmd->data_length) {
			pr_err("%s() write returned %d\n", __func__, ret);
			return (ret < 0 ? ret : -EINVAL);
		}
	} else {
		/*
		 * 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(file_inode(fd)->i_mode)) {
			if (ret < 0 || ret != cmd->data_length) {
				pr_err("%s() returned %d, expecting %u for "
						"S_ISBLK\n", __func__, ret,
						cmd->data_length);
				return (ret < 0 ? ret : -EINVAL);
			}
		} else {
			if (ret < 0) {
				pr_err("%s() returned %d for non S_ISBLK\n",
						__func__, ret);
				return ret;
			}
		}
	}
	return 1;
}

static sense_reason_t
fd_execute_sync_cache(struct se_cmd *cmd)
{
	struct se_device *dev = cmd->se_dev;
	struct fd_dev *fd_dev = FD_DEV(dev);
	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)
		target_complete_cmd(cmd, SAM_STAT_GOOD);

	/*
	 * 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->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)
		return 0;

	if (ret)
		target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
	else
		target_complete_cmd(cmd, SAM_STAT_GOOD);

	return 0;
}

static unsigned char *
fd_setup_write_same_buf(struct se_cmd *cmd, struct scatterlist *sg,
		    unsigned int len)
{
	struct se_device *se_dev = cmd->se_dev;
	unsigned int block_size = se_dev->dev_attrib.block_size;
	unsigned int i = 0, end;
	unsigned char *buf, *p, *kmap_buf;

	buf = kzalloc(min_t(unsigned int, len, PAGE_SIZE), GFP_KERNEL);
	if (!buf) {
		pr_err("Unable to allocate fd_execute_write_same buf\n");
		return NULL;
	}

	kmap_buf = kmap(sg_page(sg)) + sg->offset;
	if (!kmap_buf) {
		pr_err("kmap() failed in fd_setup_write_same\n");
		kfree(buf);
		return NULL;
	}
	/*
	 * Fill local *buf to contain multiple WRITE_SAME blocks up to
	 * min(len, PAGE_SIZE)
	 */
	p = buf;
	end = min_t(unsigned int, len, PAGE_SIZE);


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