diff options
Diffstat (limited to 'drivers/block/pmem.c')
-rw-r--r-- | drivers/block/pmem.c | 262 |
1 files changed, 0 insertions, 262 deletions
diff --git a/drivers/block/pmem.c b/drivers/block/pmem.c deleted file mode 100644 index eabf4a8d0..000000000 --- a/drivers/block/pmem.c +++ /dev/null @@ -1,262 +0,0 @@ -/* - * Persistent Memory Driver - * - * Copyright (c) 2014, Intel Corporation. - * Copyright (c) 2015, Christoph Hellwig <hch@lst.de>. - * Copyright (c) 2015, Boaz Harrosh <boaz@plexistor.com>. - * - * This program is free software; you can redistribute it and/or modify it - * under the terms and conditions of the GNU General Public License, - * version 2, as published by the Free Software Foundation. - * - * This program is distributed in the hope 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. - */ - -#include <asm/cacheflush.h> -#include <linux/blkdev.h> -#include <linux/hdreg.h> -#include <linux/init.h> -#include <linux/platform_device.h> -#include <linux/module.h> -#include <linux/moduleparam.h> -#include <linux/slab.h> - -#define PMEM_MINORS 16 - -struct pmem_device { - struct request_queue *pmem_queue; - struct gendisk *pmem_disk; - - /* One contiguous memory region per device */ - phys_addr_t phys_addr; - void *virt_addr; - size_t size; -}; - -static int pmem_major; -static atomic_t pmem_index; - -static void pmem_do_bvec(struct pmem_device *pmem, struct page *page, - unsigned int len, unsigned int off, int rw, - sector_t sector) -{ - void *mem = kmap_atomic(page); - size_t pmem_off = sector << 9; - - if (rw == READ) { - memcpy(mem + off, pmem->virt_addr + pmem_off, len); - flush_dcache_page(page); - } else { - flush_dcache_page(page); - memcpy(pmem->virt_addr + pmem_off, mem + off, len); - } - - kunmap_atomic(mem); -} - -static void pmem_make_request(struct request_queue *q, struct bio *bio) -{ - struct block_device *bdev = bio->bi_bdev; - struct pmem_device *pmem = bdev->bd_disk->private_data; - int rw; - struct bio_vec bvec; - sector_t sector; - struct bvec_iter iter; - int err = 0; - - if (bio_end_sector(bio) > get_capacity(bdev->bd_disk)) { - err = -EIO; - goto out; - } - - BUG_ON(bio->bi_rw & REQ_DISCARD); - - rw = bio_data_dir(bio); - sector = bio->bi_iter.bi_sector; - bio_for_each_segment(bvec, bio, iter) { - pmem_do_bvec(pmem, bvec.bv_page, bvec.bv_len, bvec.bv_offset, - rw, sector); - sector += bvec.bv_len >> 9; - } - -out: - bio_endio(bio, err); -} - -static int pmem_rw_page(struct block_device *bdev, sector_t sector, - struct page *page, int rw) -{ - struct pmem_device *pmem = bdev->bd_disk->private_data; - - pmem_do_bvec(pmem, page, PAGE_CACHE_SIZE, 0, rw, sector); - page_endio(page, rw & WRITE, 0); - - return 0; -} - -static long pmem_direct_access(struct block_device *bdev, sector_t sector, - void **kaddr, unsigned long *pfn, long size) -{ - struct pmem_device *pmem = bdev->bd_disk->private_data; - size_t offset = sector << 9; - - if (!pmem) - return -ENODEV; - - *kaddr = pmem->virt_addr + offset; - *pfn = (pmem->phys_addr + offset) >> PAGE_SHIFT; - - return pmem->size - offset; -} - -static const struct block_device_operations pmem_fops = { - .owner = THIS_MODULE, - .rw_page = pmem_rw_page, - .direct_access = pmem_direct_access, -}; - -static struct pmem_device *pmem_alloc(struct device *dev, struct resource *res) -{ - struct pmem_device *pmem; - struct gendisk *disk; - int idx, err; - - err = -ENOMEM; - pmem = kzalloc(sizeof(*pmem), GFP_KERNEL); - if (!pmem) - goto out; - - pmem->phys_addr = res->start; - pmem->size = resource_size(res); - - err = -EINVAL; - if (!request_mem_region(pmem->phys_addr, pmem->size, "pmem")) { - dev_warn(dev, "could not reserve region [0x%pa:0x%zx]\n", &pmem->phys_addr, pmem->size); - goto out_free_dev; - } - - /* - * Map the memory as non-cachable, as we can't write back the contents - * of the CPU caches in case of a crash. - */ - err = -ENOMEM; - pmem->virt_addr = ioremap_nocache(pmem->phys_addr, pmem->size); - if (!pmem->virt_addr) - goto out_release_region; - - pmem->pmem_queue = blk_alloc_queue(GFP_KERNEL); - if (!pmem->pmem_queue) - goto out_unmap; - - blk_queue_make_request(pmem->pmem_queue, pmem_make_request); - blk_queue_max_hw_sectors(pmem->pmem_queue, 1024); - blk_queue_bounce_limit(pmem->pmem_queue, BLK_BOUNCE_ANY); - - disk = alloc_disk(PMEM_MINORS); - if (!disk) - goto out_free_queue; - - idx = atomic_inc_return(&pmem_index) - 1; - - disk->major = pmem_major; - disk->first_minor = PMEM_MINORS * idx; - disk->fops = &pmem_fops; - disk->private_data = pmem; - disk->queue = pmem->pmem_queue; - disk->flags = GENHD_FL_EXT_DEVT; - sprintf(disk->disk_name, "pmem%d", idx); - disk->driverfs_dev = dev; - set_capacity(disk, pmem->size >> 9); - pmem->pmem_disk = disk; - - add_disk(disk); - - return pmem; - -out_free_queue: - blk_cleanup_queue(pmem->pmem_queue); -out_unmap: - iounmap(pmem->virt_addr); -out_release_region: - release_mem_region(pmem->phys_addr, pmem->size); -out_free_dev: - kfree(pmem); -out: - return ERR_PTR(err); -} - -static void pmem_free(struct pmem_device *pmem) -{ - del_gendisk(pmem->pmem_disk); - put_disk(pmem->pmem_disk); - blk_cleanup_queue(pmem->pmem_queue); - iounmap(pmem->virt_addr); - release_mem_region(pmem->phys_addr, pmem->size); - kfree(pmem); -} - -static int pmem_probe(struct platform_device *pdev) -{ - struct pmem_device *pmem; - struct resource *res; - - if (WARN_ON(pdev->num_resources > 1)) - return -ENXIO; - - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!res) - return -ENXIO; - - pmem = pmem_alloc(&pdev->dev, res); - if (IS_ERR(pmem)) - return PTR_ERR(pmem); - - platform_set_drvdata(pdev, pmem); - - return 0; -} - -static int pmem_remove(struct platform_device *pdev) -{ - struct pmem_device *pmem = platform_get_drvdata(pdev); - - pmem_free(pmem); - return 0; -} - -static struct platform_driver pmem_driver = { - .probe = pmem_probe, - .remove = pmem_remove, - .driver = { - .owner = THIS_MODULE, - .name = "pmem", - }, -}; - -static int __init pmem_init(void) -{ - int error; - - pmem_major = register_blkdev(0, "pmem"); - if (pmem_major < 0) - return pmem_major; - - error = platform_driver_register(&pmem_driver); - if (error) - unregister_blkdev(pmem_major, "pmem"); - return error; -} -module_init(pmem_init); - -static void pmem_exit(void) -{ - platform_driver_unregister(&pmem_driver); - unregister_blkdev(pmem_major, "pmem"); -} -module_exit(pmem_exit); - -MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>"); -MODULE_LICENSE("GPL v2"); |