/** Filename: dev.c*** Authors: Joshua Morris <josh.h.morris@us.ibm.com>*	Philip Kelleher <pjk1939@linux.vnet.ibm.com>** (C) Copyright 2013 IBM Corporation** 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/kernel.h>#include <linux/interrupt.h>#include <linux/module.h>#include <linux/pci.h>#include <linux/slab.h> #include <linux/hdreg.h>#include <linux/genhd.h>#include <linux/blkdev.h>#include <linux/bio.h> #include <linux/fs.h> #include "rsxx_priv.h" static unsigned int blkdev_minors = 64;module_param(blkdev_minors, uint, 0444);MODULE_PARM_DESC(blkdev_minors, "Number of minors(partitions)"); /* * For now I'm making this tweakable in case any applications hit this limit. * If you see a "bio too big" error in the log you will need to raise this * value. */static unsigned int blkdev_max_hw_sectors = 1024;module_param(blkdev_max_hw_sectors, uint, 0444);MODULE_PARM_DESC(blkdev_max_hw_sectors, "Max hw sectors for a single BIO"); static unsigned int enable_blkdev = 1;module_param(enable_blkdev , uint, 0444);MODULE_PARM_DESC(enable_blkdev, "Enable block device interfaces");  struct rsxx_bio_meta {	struct bio	*bio;	atomic_t	pending_dmas;	atomic_t	error;	unsigned long	start_time;}; static struct kmem_cache *bio_meta_pool; /*----------------- Block Device Operations -----------------*/static int rsxx_blkdev_ioctl(struct block_device *bdev,				 fmode_t mode,				 unsigned int cmd,				 unsigned long arg){	struct rsxx_cardinfo *card = bdev->bd_disk->private_data; 	switch (cmd) {	case RSXX_GETREG:		return rsxx_reg_access(card, (void __user *)arg, 1);	case RSXX_SETREG:		return rsxx_reg_access(card, (void __user *)arg, 0);	} 	return -ENOTTY;} static int rsxx_getgeo(struct block_device *bdev, struct hd_geometry *geo){	struct rsxx_cardinfo *card = bdev->bd_disk->private_data;	u64 blocks = card->size8 >> 9; 	/*	 * get geometry: Fake it. I haven't found any drivers that set	 * geo->start, so we won't either.	 */	if (card->size8) {		geo->heads = 64;		geo->sectors = 16;		do_div(blocks, (geo->heads * geo->sectors));		geo->cylinders = blocks;	} else {		geo->heads = 0;		geo->sectors = 0;		geo->cylinders = 0;	}	return 0;} static const struct block_device_operations rsxx_fops = {	.owner		= THIS_MODULE,	.getgeo		= rsxx_getgeo,	.ioctl		= rsxx_blkdev_ioctl,}; static void disk_stats_start(struct rsxx_cardinfo *card, struct bio *bio){	generic_start_io_acct(bio_data_dir(bio), bio_sectors(bio),			     &card->gendisk->part0);} static void disk_stats_complete(struct rsxx_cardinfo *card,				struct bio *bio,				unsigned long start_time){	generic_end_io_acct(bio_data_dir(bio), &card->gendisk->part0,			   start_time);} static void bio_dma_done_cb(struct rsxx_cardinfo *card,			    void *cb_data,			    unsigned int error){	struct rsxx_bio_meta *meta = cb_data; 	if (error)		atomic_set(&meta->error, 1); 	if (atomic_dec_and_test(&meta->pending_dmas)) {		if (!card->eeh_state && card->gendisk)			disk_stats_complete(card, meta->bio, meta->start_time); 		if (atomic_read(&meta->error))			bio_io_error(meta->bio);		else			bio_endio(meta->bio);		kmem_cache_free(bio_meta_pool, meta);	}} static blk_qc_t rsxx_make_request(struct request_queue *q, struct bio *bio){	struct rsxx_cardinfo *card = q->queuedata;	struct rsxx_bio_meta *bio_meta;	blk_status_t st = BLK_STS_IOERR; 	blk_queue_split(q, &bio); 	might_sleep(); 	if (!card)		goto req_err; 	if (bio_end_sector(bio) > get_capacity(card->gendisk))		goto req_err; 	if (unlikely(card->halt))		goto req_err; 	if (unlikely(card->dma_fault))		goto req_err; 	if (bio->bi_iter.bi_size == 0) {		dev_err(CARD_TO_DEV(card), "size zero BIO!\n");		goto req_err;	} 	bio_meta = kmem_cache_alloc(bio_meta_pool, GFP_KERNEL);	if (!bio_meta) {		st = BLK_STS_RESOURCE;		goto req_err;	} 	bio_meta->bio = bio;	atomic_set(&bio_meta->error, 0);	atomic_set(&bio_meta->pending_dmas, 0);	bio_meta->start_time = jiffies; 	if (!unlikely(card->halt))		disk_stats_start(card, bio); 	dev_dbg(CARD_TO_DEV(card), "BIO[%c]: meta: %p addr8: x%llx size: %d\n",		 bio_data_dir(bio) ? 'W' : 'R', bio_meta,		 (u64)bio->bi_iter.bi_sector << 9, bio->bi_iter.bi_size); 	st = rsxx_dma_queue_bio(card, bio, &bio_meta->pending_dmas,				    bio_dma_done_cb, bio_meta);	if (st)		goto queue_err; 	return BLK_QC_T_NONE; queue_err:	kmem_cache_free(bio_meta_pool, bio_meta);req_err:	if (st)		bio->bi_status = st;	bio_endio(bio);	return BLK_QC_T_NONE;} /*----------------- Device Setup -------------------*/static bool rsxx_discard_supported(struct rsxx_cardinfo *card){	unsigned char pci_rev; 	pci_read_config_byte(card->dev, PCI_REVISION_ID, &pci_rev); 	return (pci_rev >= RSXX_DISCARD_SUPPORT);} int rsxx_attach_dev(struct rsxx_cardinfo *card){	mutex_lock(&card->dev_lock); 	/* The block device requires the stripe size from the config. */	if (enable_blkdev) {		if (card->config_valid)			set_capacity(card->gendisk, card->size8 >> 9);		else			set_capacity(card->gendisk, 0);		device_add_disk(CARD_TO_DEV(card), card->gendisk);		card->bdev_attached = 1;	} 	mutex_unlock(&card->dev_lock); 	return 0;} void rsxx_detach_dev(struct rsxx_cardinfo *card){	mutex_lock(&card->dev_lock); 	if (card->bdev_attached) {		del_gendisk(card->gendisk);		card->bdev_attached = 0;	} 	mutex_unlock(&card->dev_lock);} int rsxx_setup_dev(struct rsxx_cardinfo *card){	unsigned short blk_size; 	mutex_init(&card->dev_lock); 	if (!enable_blkdev)		return 0; 	card->major = register_blkdev(0, DRIVER_NAME);	if (card->major < 0) {		dev_err(CARD_TO_DEV(card), "Failed to get major number\n");		return -ENOMEM;	} 	card->queue = blk_alloc_queue(GFP_KERNEL);	if (!card->queue) {		dev_err(CARD_TO_DEV(card), "Failed queue alloc\n");		unregister_blkdev(card->major, DRIVER_NAME);		return -ENOMEM;	} 	card->gendisk = alloc_disk(blkdev_minors);	if (!card->gendisk) {		dev_err(CARD_TO_DEV(card), "Failed disk alloc\n");		blk_cleanup_queue(card->queue);		unregister_blkdev(card->major, DRIVER_NAME);		return -ENOMEM;	} 	if (card->config_valid) {		blk_size = card->config.data.block_size;		blk_queue_dma_alignment(card->queue, blk_size - 1);		blk_queue_logical_block_size(card->queue, blk_size);	} 	blk_queue_make_request(card->queue, rsxx_make_request);	blk_queue_max_hw_sectors(card->queue, blkdev_max_hw_sectors);	blk_queue_physical_block_size(card->queue, RSXX_HW_BLK_SIZE); 	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, card->queue);	queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, card->queue);	if (rsxx_discard_supported(card)) {		queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, card->queue);		blk_queue_max_discard_sectors(card->queue,						RSXX_HW_BLK_SIZE >> 9);		card->queue->limits.discard_granularity = RSXX_HW_BLK_SIZE;		card->queue->limits.discard_alignment   = RSXX_HW_BLK_SIZE;	} 	card->queue->queuedata = card; 	snprintf(card->gendisk->disk_name, sizeof(card->gendisk->disk_name),		 "rsxx%d", card->disk_id);	card->gendisk->major = card->major;	card->gendisk->first_minor = 0;	card->gendisk->fops = &rsxx_fops;	card->gendisk->private_data = card;	card->gendisk->queue = card->queue; 	return 0;} void rsxx_destroy_dev(struct rsxx_cardinfo *card){	if (!enable_blkdev)		return; 	put_disk(card->gendisk);	card->gendisk = NULL; 	blk_cleanup_queue(card->queue);	card->queue->queuedata = NULL;	unregister_blkdev(card->major, DRIVER_NAME);} int rsxx_dev_init(void){	bio_meta_pool = KMEM_CACHE(rsxx_bio_meta, SLAB_HWCACHE_ALIGN);	if (!bio_meta_pool)		return -ENOMEM; 	return 0;} void rsxx_dev_cleanup(void){	kmem_cache_destroy(bio_meta_pool);}