diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-06-29 10:34:42 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-06-29 10:34:42 -0700 |
commit | 88793e5c774ec69351ef6b5200bb59f532e41bca (patch) | |
tree | 54c4be61777ea53fde892b71e795322c5227d16e /drivers/block | |
parent | 1bc5e157ed2b4f5b206155fc772d860158acd201 (diff) | |
parent | 61031952f4c89dba1065f7a5b9419badb112554c (diff) |
Merge tag 'libnvdimm-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm
Pull libnvdimm subsystem from Dan Williams:
"The libnvdimm sub-system introduces, in addition to the
libnvdimm-core, 4 drivers / enabling modules:
NFIT:
Instantiates an "nvdimm bus" with the core and registers memory
devices (NVDIMMs) enumerated by the ACPI 6.0 NFIT (NVDIMM Firmware
Interface table).
After registering NVDIMMs the NFIT driver then registers "region"
devices. A libnvdimm-region defines an access mode and the
boundaries of persistent memory media. A region may span multiple
NVDIMMs that are interleaved by the hardware memory controller. In
turn, a libnvdimm-region can be carved into a "namespace" device and
bound to the PMEM or BLK driver which will attach a Linux block
device (disk) interface to the memory.
PMEM:
Initially merged in v4.1 this driver for contiguous spans of
persistent memory address ranges is re-worked to drive
PMEM-namespaces emitted by the libnvdimm-core.
In this update the PMEM driver, on x86, gains the ability to assert
that writes to persistent memory have been flushed all the way
through the caches and buffers in the platform to persistent media.
See memcpy_to_pmem() and wmb_pmem().
BLK:
This new driver enables access to persistent memory media through
"Block Data Windows" as defined by the NFIT. The primary difference
of this driver to PMEM is that only a small window of persistent
memory is mapped into system address space at any given point in
time.
Per-NVDIMM windows are reprogrammed at run time, per-I/O, to access
different portions of the media. BLK-mode, by definition, does not
support DAX.
BTT:
This is a library, optionally consumed by either PMEM or BLK, that
converts a byte-accessible namespace into a disk with atomic sector
update semantics (prevents sector tearing on crash or power loss).
The sinister aspect of sector tearing is that most applications do
not know they have a atomic sector dependency. At least today's
disk's rarely ever tear sectors and if they do one almost certainly
gets a CRC error on access. NVDIMMs will always tear and always
silently. Until an application is audited to be robust in the
presence of sector-tearing the usage of BTT is recommended.
Thanks to: Ross Zwisler, Jeff Moyer, Vishal Verma, Christoph Hellwig,
Ingo Molnar, Neil Brown, Boaz Harrosh, Robert Elliott, Matthew Wilcox,
Andy Rudoff, Linda Knippers, Toshi Kani, Nicholas Moulin, Rafael
Wysocki, and Bob Moore"
* tag 'libnvdimm-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm: (33 commits)
arch, x86: pmem api for ensuring durability of persistent memory updates
libnvdimm: Add sysfs numa_node to NVDIMM devices
libnvdimm: Set numa_node to NVDIMM devices
acpi: Add acpi_map_pxm_to_online_node()
libnvdimm, nfit: handle unarmed dimms, mark namespaces read-only
pmem: flag pmem block devices as non-rotational
libnvdimm: enable iostat
pmem: make_request cleanups
libnvdimm, pmem: fix up max_hw_sectors
libnvdimm, blk: add support for blk integrity
libnvdimm, btt: add support for blk integrity
fs/block_dev.c: skip rw_page if bdev has integrity
libnvdimm: Non-Volatile Devices
tools/testing/nvdimm: libnvdimm unit test infrastructure
libnvdimm, nfit, nd_blk: driver for BLK-mode access persistent memory
nd_btt: atomic sector updates
libnvdimm: infrastructure for btt devices
libnvdimm: write blk label set
libnvdimm: write pmem label set
libnvdimm: blk labels and namespace instantiation
...
Diffstat (limited to 'drivers/block')
-rw-r--r-- | drivers/block/Kconfig | 12 | ||||
-rw-r--r-- | drivers/block/Makefile | 1 | ||||
-rw-r--r-- | drivers/block/pmem.c | 262 |
3 files changed, 0 insertions, 275 deletions
diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig index 3ccef9eba6f9..1b8094d4d7af 100644 --- a/drivers/block/Kconfig +++ b/drivers/block/Kconfig @@ -404,18 +404,6 @@ config BLK_DEV_RAM_DAX and will prevent RAM block device backing store memory from being allocated from highmem (only a problem for highmem systems). -config BLK_DEV_PMEM - tristate "Persistent memory block device support" - depends on HAS_IOMEM - help - Saying Y here will allow you to use a contiguous range of reserved - memory as one or more persistent block devices. - - To compile this driver as a module, choose M here: the module will be - called 'pmem'. - - If unsure, say N. - config CDROM_PKTCDVD tristate "Packet writing on CD/DVD media" depends on !UML diff --git a/drivers/block/Makefile b/drivers/block/Makefile index 9cc6c18a1c7e..02b688d1438d 100644 --- a/drivers/block/Makefile +++ b/drivers/block/Makefile @@ -14,7 +14,6 @@ obj-$(CONFIG_PS3_VRAM) += ps3vram.o obj-$(CONFIG_ATARI_FLOPPY) += ataflop.o obj-$(CONFIG_AMIGA_Z2RAM) += z2ram.o obj-$(CONFIG_BLK_DEV_RAM) += brd.o -obj-$(CONFIG_BLK_DEV_PMEM) += pmem.o obj-$(CONFIG_BLK_DEV_LOOP) += loop.o obj-$(CONFIG_BLK_CPQ_DA) += cpqarray.o obj-$(CONFIG_BLK_CPQ_CISS_DA) += cciss.o diff --git a/drivers/block/pmem.c b/drivers/block/pmem.c deleted file mode 100644 index 095dfaadcaa5..000000000000 --- 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 write-through, as we can't write back the contents - * of the CPU caches in case of a crash. - */ - err = -ENOMEM; - pmem->virt_addr = ioremap_wt(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"); |