linux-stable/drivers/nvdimm/pmem.c
Linus Torvalds 53ef7d0e20 libnvdimm for 4.12
* Region media error reporting: A libnvdimm region device is the parent
 to one or more namespaces. To date, media errors have been reported via
 the "badblocks" attribute attached to pmem block devices for namespaces
 in "raw" or "memory" mode. Given that namespaces can be in "device-dax"
 or "btt-sector" mode this new interface reports media errors
 generically, i.e. independent of namespace modes or state. This
 subsequently allows userspace tooling to craft "ACPI 6.1 Section
 9.20.7.6 Function Index 4 - Clear Uncorrectable Error" requests and
 submit them via the ioctl path for NVDIMM root bus devices.
 
 * Introduce 'struct dax_device' and 'struct dax_operations': Prompted by
 a request from Linus and feedback from Christoph this allows for dax
 capable drivers to publish their own custom dax operations. This fixes
 the broken assumption that all dax operations are related to a
 persistent memory device, and makes it easier for other architectures
 and platforms to add customized persistent memory support.
 
 * 'libnvdimm' core updates: A new "deep_flush" sysfs attribute is
 available for storage appliance applications to manually trigger memory
 controllers to drain write-pending buffers that would otherwise be
 flushed automatically by the platform ADR (asynchronous-DRAM-refresh)
 mechanism at a power loss event. Support for "locked" DIMMs is included
 to prevent namespaces from surfacing when the namespace label data area
 is locked. Finally, fixes for various reported deadlocks and crashes,
 also tagged for -stable.
 
 * ACPI / nfit driver updates: General updates of the nfit driver to add
 DSM command overrides, ACPI 6.1 health state flags support, DSM payload
 debug available by default, and various fixes.
 
 Acknowledgements that came after the branch was pushed:
 
 commmit 565851c972 "device-dax: fix sysfs attribute deadlock"
 Tested-by: Yi Zhang <yizhan@redhat.com>
 
 commit 23f4984483 "libnvdimm: rework region badblocks clearing"
 Tested-by: Toshi Kani <toshi.kani@hpe.com>
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Merge tag 'libnvdimm-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "The bulk of this has been in multiple -next releases. There were a few
  late breaking fixes and small features that got added in the last
  couple days, but the whole set has received a build success
  notification from the kbuild robot.

  Change summary:

   - Region media error reporting: A libnvdimm region device is the
     parent to one or more namespaces. To date, media errors have been
     reported via the "badblocks" attribute attached to pmem block
     devices for namespaces in "raw" or "memory" mode. Given that
     namespaces can be in "device-dax" or "btt-sector" mode this new
     interface reports media errors generically, i.e. independent of
     namespace modes or state.

     This subsequently allows userspace tooling to craft "ACPI 6.1
     Section 9.20.7.6 Function Index 4 - Clear Uncorrectable Error"
     requests and submit them via the ioctl path for NVDIMM root bus
     devices.

   - Introduce 'struct dax_device' and 'struct dax_operations': Prompted
     by a request from Linus and feedback from Christoph this allows for
     dax capable drivers to publish their own custom dax operations.
     This fixes the broken assumption that all dax operations are
     related to a persistent memory device, and makes it easier for
     other architectures and platforms to add customized persistent
     memory support.

   - 'libnvdimm' core updates: A new "deep_flush" sysfs attribute is
     available for storage appliance applications to manually trigger
     memory controllers to drain write-pending buffers that would
     otherwise be flushed automatically by the platform ADR
     (asynchronous-DRAM-refresh) mechanism at a power loss event.
     Support for "locked" DIMMs is included to prevent namespaces from
     surfacing when the namespace label data area is locked. Finally,
     fixes for various reported deadlocks and crashes, also tagged for
     -stable.

   - ACPI / nfit driver updates: General updates of the nfit driver to
     add DSM command overrides, ACPI 6.1 health state flags support, DSM
     payload debug available by default, and various fixes.

  Acknowledgements that came after the branch was pushed:

   - commmit 565851c972 "device-dax: fix sysfs attribute deadlock":
     Tested-by: Yi Zhang <yizhan@redhat.com>

   - commit 23f4984483 "libnvdimm: rework region badblocks clearing"
     Tested-by: Toshi Kani <toshi.kani@hpe.com>"

* tag 'libnvdimm-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (52 commits)
  libnvdimm, pfn: fix 'npfns' vs section alignment
  libnvdimm: handle locked label storage areas
  libnvdimm: convert NDD_ flags to use bitops, introduce NDD_LOCKED
  brd: fix uninitialized use of brd->dax_dev
  block, dax: use correct format string in bdev_dax_supported
  device-dax: fix sysfs attribute deadlock
  libnvdimm: restore "libnvdimm: band aid btt vs clear poison locking"
  libnvdimm: fix nvdimm_bus_lock() vs device_lock() ordering
  libnvdimm: rework region badblocks clearing
  acpi, nfit: kill ACPI_NFIT_DEBUG
  libnvdimm: fix clear length of nvdimm_forget_poison()
  libnvdimm, pmem: fix a NULL pointer BUG in nd_pmem_notify
  libnvdimm, region: sysfs trigger for nvdimm_flush()
  libnvdimm: fix phys_addr for nvdimm_clear_poison
  x86, dax, pmem: remove indirection around memcpy_from_pmem()
  block: remove block_device_operations ->direct_access()
  block, dax: convert bdev_dax_supported() to dax_direct_access()
  filesystem-dax: convert to dax_direct_access()
  Revert "block: use DAX for partition table reads"
  ext2, ext4, xfs: retrieve dax_device for iomap operations
  ...
2017-05-05 18:49:20 -07:00

495 lines
12 KiB
C

/*
* Persistent Memory Driver
*
* Copyright (c) 2014-2015, 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/badblocks.h>
#include <linux/memremap.h>
#include <linux/vmalloc.h>
#include <linux/blk-mq.h>
#include <linux/pfn_t.h>
#include <linux/slab.h>
#include <linux/pmem.h>
#include <linux/dax.h>
#include <linux/nd.h>
#include "pmem.h"
#include "pfn.h"
#include "nd.h"
static struct device *to_dev(struct pmem_device *pmem)
{
/*
* nvdimm bus services need a 'dev' parameter, and we record the device
* at init in bb.dev.
*/
return pmem->bb.dev;
}
static struct nd_region *to_region(struct pmem_device *pmem)
{
return to_nd_region(to_dev(pmem)->parent);
}
static int pmem_clear_poison(struct pmem_device *pmem, phys_addr_t offset,
unsigned int len)
{
struct device *dev = to_dev(pmem);
sector_t sector;
long cleared;
int rc = 0;
sector = (offset - pmem->data_offset) / 512;
cleared = nvdimm_clear_poison(dev, pmem->phys_addr + offset, len);
if (cleared < len)
rc = -EIO;
if (cleared > 0 && cleared / 512) {
cleared /= 512;
dev_dbg(dev, "%s: %#llx clear %ld sector%s\n", __func__,
(unsigned long long) sector, cleared,
cleared > 1 ? "s" : "");
badblocks_clear(&pmem->bb, sector, cleared);
}
invalidate_pmem(pmem->virt_addr + offset, len);
return rc;
}
static void write_pmem(void *pmem_addr, struct page *page,
unsigned int off, unsigned int len)
{
void *mem = kmap_atomic(page);
memcpy_to_pmem(pmem_addr, mem + off, len);
kunmap_atomic(mem);
}
static int read_pmem(struct page *page, unsigned int off,
void *pmem_addr, unsigned int len)
{
int rc;
void *mem = kmap_atomic(page);
rc = memcpy_mcsafe(mem + off, pmem_addr, len);
kunmap_atomic(mem);
if (rc)
return -EIO;
return 0;
}
static int pmem_do_bvec(struct pmem_device *pmem, struct page *page,
unsigned int len, unsigned int off, bool is_write,
sector_t sector)
{
int rc = 0;
bool bad_pmem = false;
phys_addr_t pmem_off = sector * 512 + pmem->data_offset;
void *pmem_addr = pmem->virt_addr + pmem_off;
if (unlikely(is_bad_pmem(&pmem->bb, sector, len)))
bad_pmem = true;
if (!is_write) {
if (unlikely(bad_pmem))
rc = -EIO;
else {
rc = read_pmem(page, off, pmem_addr, len);
flush_dcache_page(page);
}
} else {
/*
* Note that we write the data both before and after
* clearing poison. The write before clear poison
* handles situations where the latest written data is
* preserved and the clear poison operation simply marks
* the address range as valid without changing the data.
* In this case application software can assume that an
* interrupted write will either return the new good
* data or an error.
*
* However, if pmem_clear_poison() leaves the data in an
* indeterminate state we need to perform the write
* after clear poison.
*/
flush_dcache_page(page);
write_pmem(pmem_addr, page, off, len);
if (unlikely(bad_pmem)) {
rc = pmem_clear_poison(pmem, pmem_off, len);
write_pmem(pmem_addr, page, off, len);
}
}
return rc;
}
/* account for REQ_FLUSH rename, replace with REQ_PREFLUSH after v4.8-rc1 */
#ifndef REQ_FLUSH
#define REQ_FLUSH REQ_PREFLUSH
#endif
static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio)
{
int rc = 0;
bool do_acct;
unsigned long start;
struct bio_vec bvec;
struct bvec_iter iter;
struct pmem_device *pmem = q->queuedata;
struct nd_region *nd_region = to_region(pmem);
if (bio->bi_opf & REQ_FLUSH)
nvdimm_flush(nd_region);
do_acct = nd_iostat_start(bio, &start);
bio_for_each_segment(bvec, bio, iter) {
rc = pmem_do_bvec(pmem, bvec.bv_page, bvec.bv_len,
bvec.bv_offset, op_is_write(bio_op(bio)),
iter.bi_sector);
if (rc) {
bio->bi_error = rc;
break;
}
}
if (do_acct)
nd_iostat_end(bio, start);
if (bio->bi_opf & REQ_FUA)
nvdimm_flush(nd_region);
bio_endio(bio);
return BLK_QC_T_NONE;
}
static int pmem_rw_page(struct block_device *bdev, sector_t sector,
struct page *page, bool is_write)
{
struct pmem_device *pmem = bdev->bd_queue->queuedata;
int rc;
rc = pmem_do_bvec(pmem, page, PAGE_SIZE, 0, is_write, sector);
/*
* The ->rw_page interface is subtle and tricky. The core
* retries on any error, so we can only invoke page_endio() in
* the successful completion case. Otherwise, we'll see crashes
* caused by double completion.
*/
if (rc == 0)
page_endio(page, is_write, 0);
return rc;
}
/* see "strong" declaration in tools/testing/nvdimm/pmem-dax.c */
__weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
long nr_pages, void **kaddr, pfn_t *pfn)
{
resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;
if (unlikely(is_bad_pmem(&pmem->bb, PFN_PHYS(pgoff) / 512,
PFN_PHYS(nr_pages))))
return -EIO;
*kaddr = pmem->virt_addr + offset;
*pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
/*
* If badblocks are present, limit known good range to the
* requested range.
*/
if (unlikely(pmem->bb.count))
return nr_pages;
return PHYS_PFN(pmem->size - pmem->pfn_pad - offset);
}
static const struct block_device_operations pmem_fops = {
.owner = THIS_MODULE,
.rw_page = pmem_rw_page,
.revalidate_disk = nvdimm_revalidate_disk,
};
static long pmem_dax_direct_access(struct dax_device *dax_dev,
pgoff_t pgoff, long nr_pages, void **kaddr, pfn_t *pfn)
{
struct pmem_device *pmem = dax_get_private(dax_dev);
return __pmem_direct_access(pmem, pgoff, nr_pages, kaddr, pfn);
}
static const struct dax_operations pmem_dax_ops = {
.direct_access = pmem_dax_direct_access,
};
static void pmem_release_queue(void *q)
{
blk_cleanup_queue(q);
}
static void pmem_freeze_queue(void *q)
{
blk_freeze_queue_start(q);
}
static void pmem_release_disk(void *__pmem)
{
struct pmem_device *pmem = __pmem;
kill_dax(pmem->dax_dev);
put_dax(pmem->dax_dev);
del_gendisk(pmem->disk);
put_disk(pmem->disk);
}
static int pmem_attach_disk(struct device *dev,
struct nd_namespace_common *ndns)
{
struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
struct nd_region *nd_region = to_nd_region(dev->parent);
struct vmem_altmap __altmap, *altmap = NULL;
struct resource *res = &nsio->res;
struct nd_pfn *nd_pfn = NULL;
struct dax_device *dax_dev;
int nid = dev_to_node(dev);
struct nd_pfn_sb *pfn_sb;
struct pmem_device *pmem;
struct resource pfn_res;
struct request_queue *q;
struct gendisk *disk;
void *addr;
/* while nsio_rw_bytes is active, parse a pfn info block if present */
if (is_nd_pfn(dev)) {
nd_pfn = to_nd_pfn(dev);
altmap = nvdimm_setup_pfn(nd_pfn, &pfn_res, &__altmap);
if (IS_ERR(altmap))
return PTR_ERR(altmap);
}
/* we're attaching a block device, disable raw namespace access */
devm_nsio_disable(dev, nsio);
pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL);
if (!pmem)
return -ENOMEM;
dev_set_drvdata(dev, pmem);
pmem->phys_addr = res->start;
pmem->size = resource_size(res);
if (nvdimm_has_flush(nd_region) < 0)
dev_warn(dev, "unable to guarantee persistence of writes\n");
if (!devm_request_mem_region(dev, res->start, resource_size(res),
dev_name(&ndns->dev))) {
dev_warn(dev, "could not reserve region %pR\n", res);
return -EBUSY;
}
q = blk_alloc_queue_node(GFP_KERNEL, dev_to_node(dev));
if (!q)
return -ENOMEM;
if (devm_add_action_or_reset(dev, pmem_release_queue, q))
return -ENOMEM;
pmem->pfn_flags = PFN_DEV;
if (is_nd_pfn(dev)) {
addr = devm_memremap_pages(dev, &pfn_res, &q->q_usage_counter,
altmap);
pfn_sb = nd_pfn->pfn_sb;
pmem->data_offset = le64_to_cpu(pfn_sb->dataoff);
pmem->pfn_pad = resource_size(res) - resource_size(&pfn_res);
pmem->pfn_flags |= PFN_MAP;
res = &pfn_res; /* for badblocks populate */
res->start += pmem->data_offset;
} else if (pmem_should_map_pages(dev)) {
addr = devm_memremap_pages(dev, &nsio->res,
&q->q_usage_counter, NULL);
pmem->pfn_flags |= PFN_MAP;
} else
addr = devm_memremap(dev, pmem->phys_addr,
pmem->size, ARCH_MEMREMAP_PMEM);
/*
* At release time the queue must be frozen before
* devm_memremap_pages is unwound
*/
if (devm_add_action_or_reset(dev, pmem_freeze_queue, q))
return -ENOMEM;
if (IS_ERR(addr))
return PTR_ERR(addr);
pmem->virt_addr = addr;
blk_queue_write_cache(q, true, true);
blk_queue_make_request(q, pmem_make_request);
blk_queue_physical_block_size(q, PAGE_SIZE);
blk_queue_max_hw_sectors(q, UINT_MAX);
blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
queue_flag_set_unlocked(QUEUE_FLAG_NONROT, q);
queue_flag_set_unlocked(QUEUE_FLAG_DAX, q);
q->queuedata = pmem;
disk = alloc_disk_node(0, nid);
if (!disk)
return -ENOMEM;
pmem->disk = disk;
disk->fops = &pmem_fops;
disk->queue = q;
disk->flags = GENHD_FL_EXT_DEVT;
nvdimm_namespace_disk_name(ndns, disk->disk_name);
set_capacity(disk, (pmem->size - pmem->pfn_pad - pmem->data_offset)
/ 512);
if (devm_init_badblocks(dev, &pmem->bb))
return -ENOMEM;
nvdimm_badblocks_populate(nd_region, &pmem->bb, res);
disk->bb = &pmem->bb;
dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops);
if (!dax_dev) {
put_disk(disk);
return -ENOMEM;
}
pmem->dax_dev = dax_dev;
device_add_disk(dev, disk);
if (devm_add_action_or_reset(dev, pmem_release_disk, pmem))
return -ENOMEM;
revalidate_disk(disk);
return 0;
}
static int nd_pmem_probe(struct device *dev)
{
struct nd_namespace_common *ndns;
ndns = nvdimm_namespace_common_probe(dev);
if (IS_ERR(ndns))
return PTR_ERR(ndns);
if (devm_nsio_enable(dev, to_nd_namespace_io(&ndns->dev)))
return -ENXIO;
if (is_nd_btt(dev))
return nvdimm_namespace_attach_btt(ndns);
if (is_nd_pfn(dev))
return pmem_attach_disk(dev, ndns);
/* if we find a valid info-block we'll come back as that personality */
if (nd_btt_probe(dev, ndns) == 0 || nd_pfn_probe(dev, ndns) == 0
|| nd_dax_probe(dev, ndns) == 0)
return -ENXIO;
/* ...otherwise we're just a raw pmem device */
return pmem_attach_disk(dev, ndns);
}
static int nd_pmem_remove(struct device *dev)
{
if (is_nd_btt(dev))
nvdimm_namespace_detach_btt(to_nd_btt(dev));
nvdimm_flush(to_nd_region(dev->parent));
return 0;
}
static void nd_pmem_shutdown(struct device *dev)
{
nvdimm_flush(to_nd_region(dev->parent));
}
static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
{
struct nd_region *nd_region;
resource_size_t offset = 0, end_trunc = 0;
struct nd_namespace_common *ndns;
struct nd_namespace_io *nsio;
struct resource res;
struct badblocks *bb;
if (event != NVDIMM_REVALIDATE_POISON)
return;
if (is_nd_btt(dev)) {
struct nd_btt *nd_btt = to_nd_btt(dev);
ndns = nd_btt->ndns;
nd_region = to_nd_region(ndns->dev.parent);
nsio = to_nd_namespace_io(&ndns->dev);
bb = &nsio->bb;
} else {
struct pmem_device *pmem = dev_get_drvdata(dev);
nd_region = to_region(pmem);
bb = &pmem->bb;
if (is_nd_pfn(dev)) {
struct nd_pfn *nd_pfn = to_nd_pfn(dev);
struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
ndns = nd_pfn->ndns;
offset = pmem->data_offset +
__le32_to_cpu(pfn_sb->start_pad);
end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
} else {
ndns = to_ndns(dev);
}
nsio = to_nd_namespace_io(&ndns->dev);
}
res.start = nsio->res.start + offset;
res.end = nsio->res.end - end_trunc;
nvdimm_badblocks_populate(nd_region, bb, &res);
}
MODULE_ALIAS("pmem");
MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO);
MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_PMEM);
static struct nd_device_driver nd_pmem_driver = {
.probe = nd_pmem_probe,
.remove = nd_pmem_remove,
.notify = nd_pmem_notify,
.shutdown = nd_pmem_shutdown,
.drv = {
.name = "nd_pmem",
},
.type = ND_DRIVER_NAMESPACE_IO | ND_DRIVER_NAMESPACE_PMEM,
};
static int __init pmem_init(void)
{
return nd_driver_register(&nd_pmem_driver);
}
module_init(pmem_init);
static void pmem_exit(void)
{
driver_unregister(&nd_pmem_driver.drv);
}
module_exit(pmem_exit);
MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>");
MODULE_LICENSE("GPL v2");