--- /dev/null
+/*
+* 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);
+
+ bio_endio(meta->bio, atomic_read(&meta->error) ? -EIO : 0);
+ kmem_cache_free(bio_meta_pool, meta);
+ }
+}
+
+static void rsxx_make_request(struct request_queue *q, struct bio *bio)
+{
+ struct rsxx_cardinfo *card = q->queuedata;
+ struct rsxx_bio_meta *bio_meta;
+ int st = -EINVAL;
+
+ might_sleep();
+
+ if (!card)
+ goto req_err;
+
+ if (bio_end_sector(bio) > get_capacity(card->gendisk))
+ goto req_err;
+
+ if (unlikely(card->halt)) {
+ st = -EFAULT;
+ goto req_err;
+ }
+
+ if (unlikely(card->dma_fault)) {
+ st = (-EFAULT);
+ 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 = -ENOMEM;
+ 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;
+
+queue_err:
+ kmem_cache_free(bio_meta_pool, bio_meta);
+req_err:
+ bio_endio(bio, st);
+}
+
+/*----------------- 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);
+ add_disk(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_bounce_limit(card->queue, BLK_BOUNCE_ANY);
+ 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->limits.discard_zeroes_data = 1;
+ }
+
+ card->queue->queuedata = card;
+
+ snprintf(card->gendisk->disk_name, sizeof(card->gendisk->disk_name),
+ "rsxx%d", card->disk_id);
+ card->gendisk->driverfs_dev = &card->dev->dev;
+ 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);
+}
+
+
Code Review / kvmfornfv.git / blobdiff