| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * Filename: dev.c |
| * |
| * Authors: Joshua Morris <josh.h.morris@us.ibm.com> |
| * Philip Kelleher <pjk1939@linux.vnet.ibm.com> |
| * |
| * (C) Copyright 2013 IBM Corporation |
| */ |
| |
| #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(card->queue, bio_op(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(card->queue, bio_op(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, NULL); |
| 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(rsxx_make_request, NUMA_NO_NODE); |
| 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_max_hw_sectors(card->queue, blkdev_max_hw_sectors); |
| blk_queue_physical_block_size(card->queue, RSXX_HW_BLK_SIZE); |
| |
| blk_queue_flag_set(QUEUE_FLAG_NONROT, card->queue); |
| blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, card->queue); |
| if (rsxx_discard_supported(card)) { |
| blk_queue_flag_set(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); |
| } |
| |
| |