OpenCloudOS-Kernel/drivers/nvdimm/bus.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/libnvdimm.h>
#include <linux/sched/mm.h>
2015-06-09 02:27:06 +08:00
#include <linux/vmalloc.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/fcntl.h>
#include <linux/async.h>
#include <linux/genhd.h>
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#include <linux/ndctl.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/cpu.h>
#include <linux/fs.h>
#include <linux/io.h>
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#include <linux/mm.h>
#include <linux/nd.h>
#include "nd-core.h"
#include "nd.h"
#include "pfn.h"
2015-06-09 02:27:06 +08:00
int nvdimm_major;
static int nvdimm_bus_major;
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
struct class *nd_class;
static DEFINE_IDA(nd_ida);
static int to_nd_device_type(struct device *dev)
{
if (is_nvdimm(dev))
return ND_DEVICE_DIMM;
else if (is_memory(dev))
return ND_DEVICE_REGION_PMEM;
else if (is_nd_blk(dev))
return ND_DEVICE_REGION_BLK;
else if (is_nd_dax(dev))
return ND_DEVICE_DAX_PMEM;
else if (is_nd_region(dev->parent))
return nd_region_to_nstype(to_nd_region(dev->parent));
return 0;
}
static int nvdimm_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
{
return add_uevent_var(env, "MODALIAS=" ND_DEVICE_MODALIAS_FMT,
to_nd_device_type(dev));
}
static struct module *to_bus_provider(struct device *dev)
{
/* pin bus providers while regions are enabled */
if (is_nd_region(dev)) {
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
return nvdimm_bus->nd_desc->module;
}
return NULL;
}
2015-05-02 01:11:27 +08:00
static void nvdimm_bus_probe_start(struct nvdimm_bus *nvdimm_bus)
{
nvdimm_bus_lock(&nvdimm_bus->dev);
nvdimm_bus->probe_active++;
nvdimm_bus_unlock(&nvdimm_bus->dev);
}
static void nvdimm_bus_probe_end(struct nvdimm_bus *nvdimm_bus)
{
nvdimm_bus_lock(&nvdimm_bus->dev);
if (--nvdimm_bus->probe_active == 0)
wake_up(&nvdimm_bus->wait);
2015-05-02 01:11:27 +08:00
nvdimm_bus_unlock(&nvdimm_bus->dev);
}
static int nvdimm_bus_probe(struct device *dev)
{
struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
struct module *provider = to_bus_provider(dev);
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
int rc;
if (!try_module_get(provider))
return -ENXIO;
dev_dbg(&nvdimm_bus->dev, "START: %s.probe(%s)\n",
dev->driver->name, dev_name(dev));
2015-05-02 01:11:27 +08:00
nvdimm_bus_probe_start(nvdimm_bus);
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
debug_nvdimm_lock(dev);
rc = nd_drv->probe(dev);
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
debug_nvdimm_unlock(dev);
if ((rc == 0 || rc == -EOPNOTSUPP) &&
dev->parent && is_nd_region(dev->parent))
nd_region_advance_seeds(to_nd_region(dev->parent), dev);
2015-05-02 01:11:27 +08:00
nvdimm_bus_probe_end(nvdimm_bus);
dev_dbg(&nvdimm_bus->dev, "END: %s.probe(%s) = %d\n", dev->driver->name,
dev_name(dev), rc);
if (rc != 0)
module_put(provider);
return rc;
}
static int nvdimm_bus_remove(struct device *dev)
{
struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
struct module *provider = to_bus_provider(dev);
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
int rc = 0;
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
if (nd_drv->remove) {
debug_nvdimm_lock(dev);
rc = nd_drv->remove(dev);
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
debug_nvdimm_unlock(dev);
}
2015-05-02 01:11:27 +08:00
dev_dbg(&nvdimm_bus->dev, "%s.remove(%s) = %d\n", dev->driver->name,
dev_name(dev), rc);
module_put(provider);
return rc;
}
static void nvdimm_bus_shutdown(struct device *dev)
{
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
struct nd_device_driver *nd_drv = NULL;
if (dev->driver)
nd_drv = to_nd_device_driver(dev->driver);
if (nd_drv && nd_drv->shutdown) {
nd_drv->shutdown(dev);
dev_dbg(&nvdimm_bus->dev, "%s.shutdown(%s)\n",
dev->driver->name, dev_name(dev));
}
}
void nd_device_notify(struct device *dev, enum nvdimm_event event)
{
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
nd_device_lock(dev);
if (dev->driver) {
struct nd_device_driver *nd_drv;
nd_drv = to_nd_device_driver(dev->driver);
if (nd_drv->notify)
nd_drv->notify(dev, event);
}
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
nd_device_unlock(dev);
}
EXPORT_SYMBOL(nd_device_notify);
void nvdimm_region_notify(struct nd_region *nd_region, enum nvdimm_event event)
{
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
if (!nvdimm_bus)
return;
/* caller is responsible for holding a reference on the device */
nd_device_notify(&nd_region->dev, event);
}
EXPORT_SYMBOL_GPL(nvdimm_region_notify);
struct clear_badblocks_context {
resource_size_t phys, cleared;
};
static int nvdimm_clear_badblocks_region(struct device *dev, void *data)
{
struct clear_badblocks_context *ctx = data;
struct nd_region *nd_region;
resource_size_t ndr_end;
sector_t sector;
/* make sure device is a region */
libnvdimm/region: Initialize bad block for volatile namespaces We do check for a bad block during namespace init and that use region bad block list. We need to initialize the bad block for volatile regions for this to work. We also observe a lockdep warning as below because the lock is not initialized correctly since we skip bad block init for volatile regions. INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. CPU: 2 PID: 1 Comm: swapper/0 Not tainted 5.3.0-rc1-15699-g3dee241c937e #149 Call Trace: [c0000000f95cb250] [c00000000147dd84] dump_stack+0xe8/0x164 (unreliable) [c0000000f95cb2a0] [c00000000022ccd8] register_lock_class+0x308/0xa60 [c0000000f95cb3a0] [c000000000229cc0] __lock_acquire+0x170/0x1ff0 [c0000000f95cb4c0] [c00000000022c740] lock_acquire+0x220/0x270 [c0000000f95cb580] [c000000000a93230] badblocks_check+0xc0/0x290 [c0000000f95cb5f0] [c000000000d97540] nd_pfn_validate+0x5c0/0x7f0 [c0000000f95cb6d0] [c000000000d98300] nd_dax_probe+0xd0/0x1f0 [c0000000f95cb760] [c000000000d9b66c] nd_pmem_probe+0x10c/0x160 [c0000000f95cb790] [c000000000d7f5ec] nvdimm_bus_probe+0x10c/0x240 [c0000000f95cb820] [c000000000d0f844] really_probe+0x254/0x4e0 [c0000000f95cb8b0] [c000000000d0fdfc] driver_probe_device+0x16c/0x1e0 [c0000000f95cb930] [c000000000d10238] device_driver_attach+0x68/0xa0 [c0000000f95cb970] [c000000000d1040c] __driver_attach+0x19c/0x1c0 [c0000000f95cb9f0] [c000000000d0c4c4] bus_for_each_dev+0x94/0x130 [c0000000f95cba50] [c000000000d0f014] driver_attach+0x34/0x50 [c0000000f95cba70] [c000000000d0e208] bus_add_driver+0x178/0x2f0 [c0000000f95cbb00] [c000000000d117c8] driver_register+0x108/0x170 [c0000000f95cbb70] [c000000000d7edb0] __nd_driver_register+0xe0/0x100 [c0000000f95cbbd0] [c000000001a6baa4] nd_pmem_driver_init+0x34/0x48 [c0000000f95cbbf0] [c0000000000106f4] do_one_initcall+0x1d4/0x4b0 [c0000000f95cbcd0] [c0000000019f499c] kernel_init_freeable+0x544/0x65c [c0000000f95cbdb0] [c000000000010d6c] kernel_init+0x2c/0x180 [c0000000f95cbe20] [c00000000000b954] ret_from_kernel_thread+0x5c/0x68 Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Link: https://lore.kernel.org/r/20190919083355.26340-1-aneesh.kumar@linux.ibm.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-09-19 16:33:55 +08:00
if (!is_memory(dev))
return 0;
nd_region = to_nd_region(dev);
ndr_end = nd_region->ndr_start + nd_region->ndr_size - 1;
/* make sure we are in the region */
if (ctx->phys < nd_region->ndr_start
|| (ctx->phys + ctx->cleared) > ndr_end)
return 0;
sector = (ctx->phys - nd_region->ndr_start) / 512;
badblocks_clear(&nd_region->bb, sector, ctx->cleared / 512);
if (nd_region->bb_state)
sysfs_notify_dirent(nd_region->bb_state);
return 0;
}
static void nvdimm_clear_badblocks_regions(struct nvdimm_bus *nvdimm_bus,
phys_addr_t phys, u64 cleared)
{
struct clear_badblocks_context ctx = {
.phys = phys,
.cleared = cleared,
};
device_for_each_child(&nvdimm_bus->dev, &ctx,
nvdimm_clear_badblocks_region);
}
static void nvdimm_account_cleared_poison(struct nvdimm_bus *nvdimm_bus,
phys_addr_t phys, u64 cleared)
{
if (cleared > 0)
badrange_forget(&nvdimm_bus->badrange, phys, cleared);
if (cleared > 0 && cleared / 512)
nvdimm_clear_badblocks_regions(nvdimm_bus, phys, cleared);
}
long nvdimm_clear_poison(struct device *dev, phys_addr_t phys,
unsigned int len)
{
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
struct nvdimm_bus_descriptor *nd_desc;
struct nd_cmd_clear_error clear_err;
struct nd_cmd_ars_cap ars_cap;
u32 clear_err_unit, mask;
unsigned int noio_flag;
int cmd_rc, rc;
if (!nvdimm_bus)
return -ENXIO;
nd_desc = nvdimm_bus->nd_desc;
/*
* if ndctl does not exist, it's PMEM_LEGACY and
* we want to just pretend everything is handled.
*/
if (!nd_desc->ndctl)
return len;
memset(&ars_cap, 0, sizeof(ars_cap));
ars_cap.address = phys;
ars_cap.length = len;
noio_flag = memalloc_noio_save();
rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, &ars_cap,
sizeof(ars_cap), &cmd_rc);
memalloc_noio_restore(noio_flag);
if (rc < 0)
return rc;
if (cmd_rc < 0)
return cmd_rc;
clear_err_unit = ars_cap.clear_err_unit;
if (!clear_err_unit || !is_power_of_2(clear_err_unit))
return -ENXIO;
mask = clear_err_unit - 1;
if ((phys | len) & mask)
return -ENXIO;
memset(&clear_err, 0, sizeof(clear_err));
clear_err.address = phys;
clear_err.length = len;
noio_flag = memalloc_noio_save();
rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_CLEAR_ERROR, &clear_err,
sizeof(clear_err), &cmd_rc);
memalloc_noio_restore(noio_flag);
if (rc < 0)
return rc;
if (cmd_rc < 0)
return cmd_rc;
nvdimm_account_cleared_poison(nvdimm_bus, phys, clear_err.cleared);
return clear_err.cleared;
}
EXPORT_SYMBOL_GPL(nvdimm_clear_poison);
static int nvdimm_bus_match(struct device *dev, struct device_driver *drv);
static struct bus_type nvdimm_bus_type = {
.name = "nd",
.uevent = nvdimm_bus_uevent,
.match = nvdimm_bus_match,
.probe = nvdimm_bus_probe,
.remove = nvdimm_bus_remove,
.shutdown = nvdimm_bus_shutdown,
};
static void nvdimm_bus_release(struct device *dev)
{
struct nvdimm_bus *nvdimm_bus;
nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
ida_simple_remove(&nd_ida, nvdimm_bus->id);
kfree(nvdimm_bus);
}
static const struct device_type nvdimm_bus_dev_type = {
.release = nvdimm_bus_release,
.groups = nvdimm_bus_attribute_groups,
};
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
bool is_nvdimm_bus(struct device *dev)
{
return dev->type == &nvdimm_bus_dev_type;
}
struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev)
{
struct device *dev;
for (dev = nd_dev; dev; dev = dev->parent)
if (is_nvdimm_bus(dev))
break;
dev_WARN_ONCE(nd_dev, !dev, "invalid dev, not on nd bus\n");
if (dev)
return to_nvdimm_bus(dev);
return NULL;
}
struct nvdimm_bus *to_nvdimm_bus(struct device *dev)
{
struct nvdimm_bus *nvdimm_bus;
nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
WARN_ON(!is_nvdimm_bus(dev));
return nvdimm_bus;
}
EXPORT_SYMBOL_GPL(to_nvdimm_bus);
struct nvdimm_bus *nvdimm_to_bus(struct nvdimm *nvdimm)
{
return to_nvdimm_bus(nvdimm->dev.parent);
}
EXPORT_SYMBOL_GPL(nvdimm_to_bus);
struct nvdimm_bus *nvdimm_bus_register(struct device *parent,
struct nvdimm_bus_descriptor *nd_desc)
{
struct nvdimm_bus *nvdimm_bus;
int rc;
nvdimm_bus = kzalloc(sizeof(*nvdimm_bus), GFP_KERNEL);
if (!nvdimm_bus)
return NULL;
INIT_LIST_HEAD(&nvdimm_bus->list);
INIT_LIST_HEAD(&nvdimm_bus->mapping_list);
init_waitqueue_head(&nvdimm_bus->wait);
nvdimm_bus->id = ida_simple_get(&nd_ida, 0, 0, GFP_KERNEL);
if (nvdimm_bus->id < 0) {
kfree(nvdimm_bus);
return NULL;
}
mutex_init(&nvdimm_bus->reconfig_mutex);
badrange_init(&nvdimm_bus->badrange);
nvdimm_bus->nd_desc = nd_desc;
nvdimm_bus->dev.parent = parent;
nvdimm_bus->dev.type = &nvdimm_bus_dev_type;
nvdimm_bus->dev.groups = nd_desc->attr_groups;
nvdimm_bus->dev.bus = &nvdimm_bus_type;
nvdimm_bus->dev.of_node = nd_desc->of_node;
dev_set_name(&nvdimm_bus->dev, "ndbus%d", nvdimm_bus->id);
rc = device_register(&nvdimm_bus->dev);
if (rc) {
dev_dbg(&nvdimm_bus->dev, "registration failed: %d\n", rc);
goto err;
}
return nvdimm_bus;
err:
put_device(&nvdimm_bus->dev);
return NULL;
}
EXPORT_SYMBOL_GPL(nvdimm_bus_register);
void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus)
{
if (!nvdimm_bus)
return;
device_unregister(&nvdimm_bus->dev);
}
EXPORT_SYMBOL_GPL(nvdimm_bus_unregister);
static int child_unregister(struct device *dev, void *data)
{
/*
* the singular ndctl class device per bus needs to be
* "device_destroy"ed, so skip it here
*
* i.e. remove classless children
*/
if (dev->class)
return 0;
if (is_nvdimm(dev)) {
struct nvdimm *nvdimm = to_nvdimm(dev);
bool dev_put = false;
/* We are shutting down. Make state frozen artificially. */
nvdimm_bus_lock(dev);
set_bit(NVDIMM_SECURITY_FROZEN, &nvdimm->sec.flags);
if (test_and_clear_bit(NDD_WORK_PENDING, &nvdimm->flags))
dev_put = true;
nvdimm_bus_unlock(dev);
cancel_delayed_work_sync(&nvdimm->dwork);
if (dev_put)
put_device(dev);
}
nd_device_unregister(dev, ND_SYNC);
return 0;
}
static void free_badrange_list(struct list_head *badrange_list)
{
struct badrange_entry *bre, *next;
list_for_each_entry_safe(bre, next, badrange_list, list) {
list_del(&bre->list);
kfree(bre);
}
list_del_init(badrange_list);
}
static int nd_bus_remove(struct device *dev)
{
struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
mutex_lock(&nvdimm_bus_list_mutex);
list_del_init(&nvdimm_bus->list);
mutex_unlock(&nvdimm_bus_list_mutex);
wait_event(nvdimm_bus->wait,
atomic_read(&nvdimm_bus->ioctl_active) == 0);
nd_synchronize();
device_for_each_child(&nvdimm_bus->dev, NULL, child_unregister);
spin_lock(&nvdimm_bus->badrange.lock);
free_badrange_list(&nvdimm_bus->badrange.list);
spin_unlock(&nvdimm_bus->badrange.lock);
nvdimm_bus_destroy_ndctl(nvdimm_bus);
return 0;
}
static int nd_bus_probe(struct device *dev)
{
struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
int rc;
rc = nvdimm_bus_create_ndctl(nvdimm_bus);
if (rc)
return rc;
mutex_lock(&nvdimm_bus_list_mutex);
list_add_tail(&nvdimm_bus->list, &nvdimm_bus_list);
mutex_unlock(&nvdimm_bus_list_mutex);
/* enable bus provider attributes to look up their local context */
dev_set_drvdata(dev, nvdimm_bus->nd_desc);
return 0;
}
static struct nd_device_driver nd_bus_driver = {
.probe = nd_bus_probe,
.remove = nd_bus_remove,
.drv = {
.name = "nd_bus",
.suppress_bind_attrs = true,
.bus = &nvdimm_bus_type,
.owner = THIS_MODULE,
.mod_name = KBUILD_MODNAME,
},
};
static int nvdimm_bus_match(struct device *dev, struct device_driver *drv)
{
struct nd_device_driver *nd_drv = to_nd_device_driver(drv);
if (is_nvdimm_bus(dev) && nd_drv == &nd_bus_driver)
return true;
return !!test_bit(to_nd_device_type(dev), &nd_drv->type);
}
static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain);
void nd_synchronize(void)
{
async_synchronize_full_domain(&nd_async_domain);
}
EXPORT_SYMBOL_GPL(nd_synchronize);
static void nd_async_device_register(void *d, async_cookie_t cookie)
{
struct device *dev = d;
if (device_add(dev) != 0) {
dev_err(dev, "%s: failed\n", __func__);
put_device(dev);
}
put_device(dev);
if (dev->parent)
put_device(dev->parent);
}
static void nd_async_device_unregister(void *d, async_cookie_t cookie)
{
struct device *dev = d;
/* flush bus operations before delete */
nvdimm_bus_lock(dev);
nvdimm_bus_unlock(dev);
device_unregister(dev);
put_device(dev);
}
void __nd_device_register(struct device *dev)
{
if (!dev)
return;
/*
* Ensure that region devices always have their NUMA node set as
* early as possible. This way we are able to make certain that
* any memory associated with the creation and the creation
* itself of the region is associated with the correct node.
*/
if (is_nd_region(dev))
set_dev_node(dev, to_nd_region(dev)->numa_node);
dev->bus = &nvdimm_bus_type;
if (dev->parent) {
get_device(dev->parent);
if (dev_to_node(dev) == NUMA_NO_NODE)
set_dev_node(dev, dev_to_node(dev->parent));
}
get_device(dev);
async_schedule_dev_domain(nd_async_device_register, dev,
&nd_async_domain);
}
void nd_device_register(struct device *dev)
{
device_initialize(dev);
__nd_device_register(dev);
}
EXPORT_SYMBOL(nd_device_register);
void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
{
bool killed;
switch (mode) {
case ND_ASYNC:
/*
* In the async case this is being triggered with the
* device lock held and the unregistration work needs to
* be moved out of line iff this is thread has won the
* race to schedule the deletion.
*/
if (!kill_device(dev))
return;
get_device(dev);
async_schedule_domain(nd_async_device_unregister, dev,
&nd_async_domain);
break;
case ND_SYNC:
/*
* In the sync case the device is being unregistered due
* to a state change of the parent. Claim the kill state
* to synchronize against other unregistration requests,
* or otherwise let the async path handle it if the
* unregistration was already queued.
*/
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
nd_device_lock(dev);
killed = kill_device(dev);
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
nd_device_unlock(dev);
if (!killed)
return;
nd_synchronize();
device_unregister(dev);
break;
}
}
EXPORT_SYMBOL(nd_device_unregister);
/**
* __nd_driver_register() - register a region or a namespace driver
* @nd_drv: driver to register
* @owner: automatically set by nd_driver_register() macro
* @mod_name: automatically set by nd_driver_register() macro
*/
int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner,
const char *mod_name)
{
struct device_driver *drv = &nd_drv->drv;
if (!nd_drv->type) {
2019-03-26 03:32:28 +08:00
pr_debug("driver type bitmask not set (%ps)\n",
__builtin_return_address(0));
return -EINVAL;
}
if (!nd_drv->probe) {
pr_debug("%s ->probe() must be specified\n", mod_name);
return -EINVAL;
}
drv->bus = &nvdimm_bus_type;
drv->owner = owner;
drv->mod_name = mod_name;
return driver_register(drv);
}
EXPORT_SYMBOL(__nd_driver_register);
int nvdimm_revalidate_disk(struct gendisk *disk)
{
struct device *dev = disk_to_dev(disk)->parent;
struct nd_region *nd_region = to_nd_region(dev->parent);
int disk_ro = get_disk_ro(disk);
/*
* Upgrade to read-only if the region is read-only preserve as
* read-only if the disk is already read-only.
*/
if (disk_ro || nd_region->ro == disk_ro)
return 0;
dev_info(dev, "%s read-only, marking %s read-only\n",
dev_name(&nd_region->dev), disk->disk_name);
set_disk_ro(disk, 1);
return 0;
}
EXPORT_SYMBOL(nvdimm_revalidate_disk);
static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n",
to_nd_device_type(dev));
}
static DEVICE_ATTR_RO(modalias);
static ssize_t devtype_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
return sprintf(buf, "%s\n", dev->type->name);
}
static DEVICE_ATTR_RO(devtype);
static struct attribute *nd_device_attributes[] = {
&dev_attr_modalias.attr,
&dev_attr_devtype.attr,
NULL,
};
/*
* nd_device_attribute_group - generic attributes for all devices on an nd bus
*/
const struct attribute_group nd_device_attribute_group = {
.attrs = nd_device_attributes,
};
static ssize_t numa_node_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%d\n", dev_to_node(dev));
}
static DEVICE_ATTR_RO(numa_node);
static int nvdimm_dev_to_target_node(struct device *dev)
{
struct device *parent = dev->parent;
struct nd_region *nd_region = NULL;
if (is_nd_region(dev))
nd_region = to_nd_region(dev);
else if (parent && is_nd_region(parent))
nd_region = to_nd_region(parent);
if (!nd_region)
return NUMA_NO_NODE;
return nd_region->target_node;
}
static ssize_t target_node_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%d\n", nvdimm_dev_to_target_node(dev));
}
static DEVICE_ATTR_RO(target_node);
static struct attribute *nd_numa_attributes[] = {
&dev_attr_numa_node.attr,
&dev_attr_target_node.attr,
NULL,
};
static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
int n)
{
struct device *dev = container_of(kobj, typeof(*dev), kobj);
if (!IS_ENABLED(CONFIG_NUMA))
return 0;
if (a == &dev_attr_target_node.attr &&
nvdimm_dev_to_target_node(dev) == NUMA_NO_NODE)
return 0;
return a->mode;
}
/*
* nd_numa_attribute_group - NUMA attributes for all devices on an nd bus
*/
const struct attribute_group nd_numa_attribute_group = {
.attrs = nd_numa_attributes,
.is_visible = nd_numa_attr_visible,
};
int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
{
dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
struct device *dev;
dev = device_create(nd_class, &nvdimm_bus->dev, devt, nvdimm_bus,
"ndctl%d", nvdimm_bus->id);
if (IS_ERR(dev))
dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %ld\n",
nvdimm_bus->id, PTR_ERR(dev));
return PTR_ERR_OR_ZERO(dev);
}
void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
{
device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
}
2015-06-09 02:27:06 +08:00
static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
[ND_CMD_IMPLEMENTED] = { },
[ND_CMD_SMART] = {
.out_num = 2,
.out_sizes = { 4, 128, },
2015-06-09 02:27:06 +08:00
},
[ND_CMD_SMART_THRESHOLD] = {
.out_num = 2,
.out_sizes = { 4, 8, },
},
[ND_CMD_DIMM_FLAGS] = {
.out_num = 2,
.out_sizes = { 4, 4 },
},
[ND_CMD_GET_CONFIG_SIZE] = {
.out_num = 3,
.out_sizes = { 4, 4, 4, },
},
[ND_CMD_GET_CONFIG_DATA] = {
.in_num = 2,
.in_sizes = { 4, 4, },
.out_num = 2,
.out_sizes = { 4, UINT_MAX, },
},
[ND_CMD_SET_CONFIG_DATA] = {
.in_num = 3,
.in_sizes = { 4, 4, UINT_MAX, },
.out_num = 1,
.out_sizes = { 4, },
},
[ND_CMD_VENDOR] = {
.in_num = 3,
.in_sizes = { 4, 4, UINT_MAX, },
.out_num = 3,
.out_sizes = { 4, 4, UINT_MAX, },
},
nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism There are currently 4 known similar but incompatible definitions of the command sets that can be sent to an NVDIMM through ACPI. It is also clear that future platform generations (ACPI or not) will continue to revise and extend the DIMM command set as new devices and use cases arrive. It is obviously untenable to continue to proliferate divergence of these command definitions, and to that end a standardization process has begun to provide for a unified specification. However, that leaves a problem about what to do with this first generation where vendors are already shipping divergence. The Linux kernel can support these initial diverged platforms without giving platform-firmware free reign to continue to diverge and compound kernel maintenance overhead. The kernel implementation can encourage standardization in two ways: 1/ Require that any function code that userspace wants to send be explicitly white-listed in the implementation. For ACPI this means function codes marked as supported by acpi_check_dsm() may only be invoked if they appear in the white-list. A function must be publicly documented before it is added to the white-list. 2/ The above restrictions can be trivially bypassed by using the "vendor-specific" payload command. However, since vendor-specific commands are by definition not publicly documented and have the potential to corrupt the kernel's view of the dimm state, we provide a toggle to disable vendor-specific operations. Enabling undefined behavior is a policy decision that can be made by the platform owner and encourages firmware implementations to choose public over private command implementations. Based on an initial patch from Jerry Hoemann Cc: Jerry Hoemann <jerry.hoemann@hpe.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-29 07:23:43 +08:00
[ND_CMD_CALL] = {
.in_num = 2,
.in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
.out_num = 1,
.out_sizes = { UINT_MAX, },
},
2015-06-09 02:27:06 +08:00
};
const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
{
if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
return &__nd_cmd_dimm_descs[cmd];
return NULL;
}
EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
[ND_CMD_IMPLEMENTED] = { },
[ND_CMD_ARS_CAP] = {
.in_num = 2,
.in_sizes = { 8, 8, },
.out_num = 4,
.out_sizes = { 4, 4, 4, 4, },
2015-06-09 02:27:06 +08:00
},
[ND_CMD_ARS_START] = {
.in_num = 5,
.in_sizes = { 8, 8, 2, 1, 5, },
.out_num = 2,
.out_sizes = { 4, 4, },
2015-06-09 02:27:06 +08:00
},
[ND_CMD_ARS_STATUS] = {
.out_num = 3,
.out_sizes = { 4, 4, UINT_MAX, },
2015-06-09 02:27:06 +08:00
},
[ND_CMD_CLEAR_ERROR] = {
.in_num = 2,
.in_sizes = { 8, 8, },
.out_num = 3,
.out_sizes = { 4, 4, 8, },
},
nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism There are currently 4 known similar but incompatible definitions of the command sets that can be sent to an NVDIMM through ACPI. It is also clear that future platform generations (ACPI or not) will continue to revise and extend the DIMM command set as new devices and use cases arrive. It is obviously untenable to continue to proliferate divergence of these command definitions, and to that end a standardization process has begun to provide for a unified specification. However, that leaves a problem about what to do with this first generation where vendors are already shipping divergence. The Linux kernel can support these initial diverged platforms without giving platform-firmware free reign to continue to diverge and compound kernel maintenance overhead. The kernel implementation can encourage standardization in two ways: 1/ Require that any function code that userspace wants to send be explicitly white-listed in the implementation. For ACPI this means function codes marked as supported by acpi_check_dsm() may only be invoked if they appear in the white-list. A function must be publicly documented before it is added to the white-list. 2/ The above restrictions can be trivially bypassed by using the "vendor-specific" payload command. However, since vendor-specific commands are by definition not publicly documented and have the potential to corrupt the kernel's view of the dimm state, we provide a toggle to disable vendor-specific operations. Enabling undefined behavior is a policy decision that can be made by the platform owner and encourages firmware implementations to choose public over private command implementations. Based on an initial patch from Jerry Hoemann Cc: Jerry Hoemann <jerry.hoemann@hpe.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-29 07:23:43 +08:00
[ND_CMD_CALL] = {
.in_num = 2,
.in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
.out_num = 1,
.out_sizes = { UINT_MAX, },
},
2015-06-09 02:27:06 +08:00
};
const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
{
if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
return &__nd_cmd_bus_descs[cmd];
return NULL;
}
EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
const struct nd_cmd_desc *desc, int idx, void *buf)
{
if (idx >= desc->in_num)
return UINT_MAX;
if (desc->in_sizes[idx] < UINT_MAX)
return desc->in_sizes[idx];
if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
struct nd_cmd_set_config_hdr *hdr = buf;
return hdr->in_length;
} else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
struct nd_cmd_vendor_hdr *hdr = buf;
return hdr->in_length;
nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism There are currently 4 known similar but incompatible definitions of the command sets that can be sent to an NVDIMM through ACPI. It is also clear that future platform generations (ACPI or not) will continue to revise and extend the DIMM command set as new devices and use cases arrive. It is obviously untenable to continue to proliferate divergence of these command definitions, and to that end a standardization process has begun to provide for a unified specification. However, that leaves a problem about what to do with this first generation where vendors are already shipping divergence. The Linux kernel can support these initial diverged platforms without giving platform-firmware free reign to continue to diverge and compound kernel maintenance overhead. The kernel implementation can encourage standardization in two ways: 1/ Require that any function code that userspace wants to send be explicitly white-listed in the implementation. For ACPI this means function codes marked as supported by acpi_check_dsm() may only be invoked if they appear in the white-list. A function must be publicly documented before it is added to the white-list. 2/ The above restrictions can be trivially bypassed by using the "vendor-specific" payload command. However, since vendor-specific commands are by definition not publicly documented and have the potential to corrupt the kernel's view of the dimm state, we provide a toggle to disable vendor-specific operations. Enabling undefined behavior is a policy decision that can be made by the platform owner and encourages firmware implementations to choose public over private command implementations. Based on an initial patch from Jerry Hoemann Cc: Jerry Hoemann <jerry.hoemann@hpe.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-29 07:23:43 +08:00
} else if (cmd == ND_CMD_CALL) {
struct nd_cmd_pkg *pkg = buf;
return pkg->nd_size_in;
2015-06-09 02:27:06 +08:00
}
return UINT_MAX;
}
EXPORT_SYMBOL_GPL(nd_cmd_in_size);
u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
acpi, nfit, libnvdimm: fix / harden ars_status output length handling Given ambiguities in the ACPI 6.1 definition of the "Output (Size)" field of the ARS (Address Range Scrub) Status command, a firmware implementation may in practice return 0, 4, or 8 to indicate that there is no output payload to process. The specification states "Size of Output Buffer in bytes, including this field.". However, 'Output Buffer' is also the name of the entire payload, and earlier in the specification it states "Max Query ARS Status Output Buffer Size: Maximum size of buffer (including the Status and Extended Status fields)". Without this fix if the BIOS happens to return 0 it causes memory corruption as evidenced by this result from the acpi_nfit_ctl() unit test. ars_status00000000: 00020000 00000000 ........ BUG: stack guard page was hit at ffffc90001750000 (stack is ffffc9000174c000..ffffc9000174ffff) kernel stack overflow (page fault): 0000 [#1] SMP DEBUG_PAGEALLOC task: ffff8803332d2ec0 task.stack: ffffc9000174c000 RIP: 0010:[<ffffffff814cfe72>] [<ffffffff814cfe72>] __memcpy+0x12/0x20 RSP: 0018:ffffc9000174f9a8 EFLAGS: 00010246 RAX: ffffc9000174fab8 RBX: 0000000000000000 RCX: 000000001fffff56 RDX: 0000000000000000 RSI: ffff8803231f5a08 RDI: ffffc90001750000 RBP: ffffc9000174fa88 R08: ffffc9000174fab0 R09: ffff8803231f54b8 R10: 0000000000000008 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000003 R15: ffff8803231f54a0 FS: 00007f3a611af640(0000) GS:ffff88033ed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90001750000 CR3: 0000000325b20000 CR4: 00000000000406e0 Stack: ffffffffa00bc60d 0000000000000008 ffffc90000000001 ffffc9000174faac 0000000000000292 ffffffffa00c24e4 ffffffffa00c2914 0000000000000000 0000000000000000 ffffffff00000003 ffff880331ae8ad0 0000000800000246 Call Trace: [<ffffffffa00bc60d>] ? acpi_nfit_ctl+0x49d/0x750 [nfit] [<ffffffffa01f4fe0>] nfit_test_probe+0x670/0xb1b [nfit_test] Cc: <stable@vger.kernel.org> Fixes: 747ffe11b440 ("libnvdimm, tools/testing/nvdimm: fix 'ars_status' output buffer sizing") Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-12-07 01:10:12 +08:00
const u32 *out_field, unsigned long remainder)
2015-06-09 02:27:06 +08:00
{
if (idx >= desc->out_num)
return UINT_MAX;
if (desc->out_sizes[idx] < UINT_MAX)
return desc->out_sizes[idx];
if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
return in_field[1];
else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
return out_field[1];
acpi, nfit, libnvdimm: fix / harden ars_status output length handling Given ambiguities in the ACPI 6.1 definition of the "Output (Size)" field of the ARS (Address Range Scrub) Status command, a firmware implementation may in practice return 0, 4, or 8 to indicate that there is no output payload to process. The specification states "Size of Output Buffer in bytes, including this field.". However, 'Output Buffer' is also the name of the entire payload, and earlier in the specification it states "Max Query ARS Status Output Buffer Size: Maximum size of buffer (including the Status and Extended Status fields)". Without this fix if the BIOS happens to return 0 it causes memory corruption as evidenced by this result from the acpi_nfit_ctl() unit test. ars_status00000000: 00020000 00000000 ........ BUG: stack guard page was hit at ffffc90001750000 (stack is ffffc9000174c000..ffffc9000174ffff) kernel stack overflow (page fault): 0000 [#1] SMP DEBUG_PAGEALLOC task: ffff8803332d2ec0 task.stack: ffffc9000174c000 RIP: 0010:[<ffffffff814cfe72>] [<ffffffff814cfe72>] __memcpy+0x12/0x20 RSP: 0018:ffffc9000174f9a8 EFLAGS: 00010246 RAX: ffffc9000174fab8 RBX: 0000000000000000 RCX: 000000001fffff56 RDX: 0000000000000000 RSI: ffff8803231f5a08 RDI: ffffc90001750000 RBP: ffffc9000174fa88 R08: ffffc9000174fab0 R09: ffff8803231f54b8 R10: 0000000000000008 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000003 R15: ffff8803231f54a0 FS: 00007f3a611af640(0000) GS:ffff88033ed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90001750000 CR3: 0000000325b20000 CR4: 00000000000406e0 Stack: ffffffffa00bc60d 0000000000000008 ffffc90000000001 ffffc9000174faac 0000000000000292 ffffffffa00c24e4 ffffffffa00c2914 0000000000000000 0000000000000000 ffffffff00000003 ffff880331ae8ad0 0000000800000246 Call Trace: [<ffffffffa00bc60d>] ? acpi_nfit_ctl+0x49d/0x750 [nfit] [<ffffffffa01f4fe0>] nfit_test_probe+0x670/0xb1b [nfit_test] Cc: <stable@vger.kernel.org> Fixes: 747ffe11b440 ("libnvdimm, tools/testing/nvdimm: fix 'ars_status' output buffer sizing") Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-12-07 01:10:12 +08:00
else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2) {
/*
* Per table 9-276 ARS Data in ACPI 6.1, out_field[1] is
* "Size of Output Buffer in bytes, including this
* field."
*/
if (out_field[1] < 4)
return 0;
/*
* ACPI 6.1 is ambiguous if 'status' is included in the
* output size. If we encounter an output size that
* overshoots the remainder by 4 bytes, assume it was
* including 'status'.
*/
libnvdimm: fix ars_status output length calculation Commit efda1b5d87cb ("acpi, nfit, libnvdimm: fix / harden ars_status output length handling") Introduced additional hardening for ambiguity in the ACPI spec for ars_status output sizing. However, it had a couple of cases mixed up. Where it should have been checking for (and returning) "out_field[1] - 4" it was using "out_field[1] - 8" and vice versa. This caused a four byte discrepancy in the buffer size passed on to the command handler, and in some cases, this caused memory corruption like: ./daxdev-errors.sh: line 76: 24104 Aborted (core dumped) ./daxdev-errors $busdev $region malloc(): memory corruption Program received signal SIGABRT, Aborted. [...] #5 0x00007ffff7865a2e in calloc () from /lib64/libc.so.6 #6 0x00007ffff7bc2970 in ndctl_bus_cmd_new_ars_status (ars_cap=ars_cap@entry=0x6153b0) at ars.c:136 #7 0x0000000000401644 in check_ars_status (check=0x7fffffffdeb0, bus=0x604c20) at daxdev-errors.c:144 #8 test_daxdev_clear_error (region_name=<optimized out>, bus_name=<optimized out>) at daxdev-errors.c:332 Cc: <stable@vger.kernel.org> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Lukasz Dorau <lukasz.dorau@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Fixes: efda1b5d87cb ("acpi, nfit, libnvdimm: fix / harden ars_status output length handling") Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Reviewed-by: Keith Busch <keith.busch@intel.com> Signed-of-by: Dave Jiang <dave.jiang@intel.com>
2018-08-11 03:23:15 +08:00
if (out_field[1] - 4 == remainder)
acpi, nfit, libnvdimm: fix / harden ars_status output length handling Given ambiguities in the ACPI 6.1 definition of the "Output (Size)" field of the ARS (Address Range Scrub) Status command, a firmware implementation may in practice return 0, 4, or 8 to indicate that there is no output payload to process. The specification states "Size of Output Buffer in bytes, including this field.". However, 'Output Buffer' is also the name of the entire payload, and earlier in the specification it states "Max Query ARS Status Output Buffer Size: Maximum size of buffer (including the Status and Extended Status fields)". Without this fix if the BIOS happens to return 0 it causes memory corruption as evidenced by this result from the acpi_nfit_ctl() unit test. ars_status00000000: 00020000 00000000 ........ BUG: stack guard page was hit at ffffc90001750000 (stack is ffffc9000174c000..ffffc9000174ffff) kernel stack overflow (page fault): 0000 [#1] SMP DEBUG_PAGEALLOC task: ffff8803332d2ec0 task.stack: ffffc9000174c000 RIP: 0010:[<ffffffff814cfe72>] [<ffffffff814cfe72>] __memcpy+0x12/0x20 RSP: 0018:ffffc9000174f9a8 EFLAGS: 00010246 RAX: ffffc9000174fab8 RBX: 0000000000000000 RCX: 000000001fffff56 RDX: 0000000000000000 RSI: ffff8803231f5a08 RDI: ffffc90001750000 RBP: ffffc9000174fa88 R08: ffffc9000174fab0 R09: ffff8803231f54b8 R10: 0000000000000008 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000003 R15: ffff8803231f54a0 FS: 00007f3a611af640(0000) GS:ffff88033ed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90001750000 CR3: 0000000325b20000 CR4: 00000000000406e0 Stack: ffffffffa00bc60d 0000000000000008 ffffc90000000001 ffffc9000174faac 0000000000000292 ffffffffa00c24e4 ffffffffa00c2914 0000000000000000 0000000000000000 ffffffff00000003 ffff880331ae8ad0 0000000800000246 Call Trace: [<ffffffffa00bc60d>] ? acpi_nfit_ctl+0x49d/0x750 [nfit] [<ffffffffa01f4fe0>] nfit_test_probe+0x670/0xb1b [nfit_test] Cc: <stable@vger.kernel.org> Fixes: 747ffe11b440 ("libnvdimm, tools/testing/nvdimm: fix 'ars_status' output buffer sizing") Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-12-07 01:10:12 +08:00
return remainder;
libnvdimm: fix ars_status output length calculation Commit efda1b5d87cb ("acpi, nfit, libnvdimm: fix / harden ars_status output length handling") Introduced additional hardening for ambiguity in the ACPI spec for ars_status output sizing. However, it had a couple of cases mixed up. Where it should have been checking for (and returning) "out_field[1] - 4" it was using "out_field[1] - 8" and vice versa. This caused a four byte discrepancy in the buffer size passed on to the command handler, and in some cases, this caused memory corruption like: ./daxdev-errors.sh: line 76: 24104 Aborted (core dumped) ./daxdev-errors $busdev $region malloc(): memory corruption Program received signal SIGABRT, Aborted. [...] #5 0x00007ffff7865a2e in calloc () from /lib64/libc.so.6 #6 0x00007ffff7bc2970 in ndctl_bus_cmd_new_ars_status (ars_cap=ars_cap@entry=0x6153b0) at ars.c:136 #7 0x0000000000401644 in check_ars_status (check=0x7fffffffdeb0, bus=0x604c20) at daxdev-errors.c:144 #8 test_daxdev_clear_error (region_name=<optimized out>, bus_name=<optimized out>) at daxdev-errors.c:332 Cc: <stable@vger.kernel.org> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Lukasz Dorau <lukasz.dorau@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Fixes: efda1b5d87cb ("acpi, nfit, libnvdimm: fix / harden ars_status output length handling") Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Reviewed-by: Keith Busch <keith.busch@intel.com> Signed-of-by: Dave Jiang <dave.jiang@intel.com>
2018-08-11 03:23:15 +08:00
return out_field[1] - 8;
acpi, nfit, libnvdimm: fix / harden ars_status output length handling Given ambiguities in the ACPI 6.1 definition of the "Output (Size)" field of the ARS (Address Range Scrub) Status command, a firmware implementation may in practice return 0, 4, or 8 to indicate that there is no output payload to process. The specification states "Size of Output Buffer in bytes, including this field.". However, 'Output Buffer' is also the name of the entire payload, and earlier in the specification it states "Max Query ARS Status Output Buffer Size: Maximum size of buffer (including the Status and Extended Status fields)". Without this fix if the BIOS happens to return 0 it causes memory corruption as evidenced by this result from the acpi_nfit_ctl() unit test. ars_status00000000: 00020000 00000000 ........ BUG: stack guard page was hit at ffffc90001750000 (stack is ffffc9000174c000..ffffc9000174ffff) kernel stack overflow (page fault): 0000 [#1] SMP DEBUG_PAGEALLOC task: ffff8803332d2ec0 task.stack: ffffc9000174c000 RIP: 0010:[<ffffffff814cfe72>] [<ffffffff814cfe72>] __memcpy+0x12/0x20 RSP: 0018:ffffc9000174f9a8 EFLAGS: 00010246 RAX: ffffc9000174fab8 RBX: 0000000000000000 RCX: 000000001fffff56 RDX: 0000000000000000 RSI: ffff8803231f5a08 RDI: ffffc90001750000 RBP: ffffc9000174fa88 R08: ffffc9000174fab0 R09: ffff8803231f54b8 R10: 0000000000000008 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000003 R15: ffff8803231f54a0 FS: 00007f3a611af640(0000) GS:ffff88033ed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90001750000 CR3: 0000000325b20000 CR4: 00000000000406e0 Stack: ffffffffa00bc60d 0000000000000008 ffffc90000000001 ffffc9000174faac 0000000000000292 ffffffffa00c24e4 ffffffffa00c2914 0000000000000000 0000000000000000 ffffffff00000003 ffff880331ae8ad0 0000000800000246 Call Trace: [<ffffffffa00bc60d>] ? acpi_nfit_ctl+0x49d/0x750 [nfit] [<ffffffffa01f4fe0>] nfit_test_probe+0x670/0xb1b [nfit_test] Cc: <stable@vger.kernel.org> Fixes: 747ffe11b440 ("libnvdimm, tools/testing/nvdimm: fix 'ars_status' output buffer sizing") Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-12-07 01:10:12 +08:00
} else if (cmd == ND_CMD_CALL) {
nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism There are currently 4 known similar but incompatible definitions of the command sets that can be sent to an NVDIMM through ACPI. It is also clear that future platform generations (ACPI or not) will continue to revise and extend the DIMM command set as new devices and use cases arrive. It is obviously untenable to continue to proliferate divergence of these command definitions, and to that end a standardization process has begun to provide for a unified specification. However, that leaves a problem about what to do with this first generation where vendors are already shipping divergence. The Linux kernel can support these initial diverged platforms without giving platform-firmware free reign to continue to diverge and compound kernel maintenance overhead. The kernel implementation can encourage standardization in two ways: 1/ Require that any function code that userspace wants to send be explicitly white-listed in the implementation. For ACPI this means function codes marked as supported by acpi_check_dsm() may only be invoked if they appear in the white-list. A function must be publicly documented before it is added to the white-list. 2/ The above restrictions can be trivially bypassed by using the "vendor-specific" payload command. However, since vendor-specific commands are by definition not publicly documented and have the potential to corrupt the kernel's view of the dimm state, we provide a toggle to disable vendor-specific operations. Enabling undefined behavior is a policy decision that can be made by the platform owner and encourages firmware implementations to choose public over private command implementations. Based on an initial patch from Jerry Hoemann Cc: Jerry Hoemann <jerry.hoemann@hpe.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-29 07:23:43 +08:00
struct nd_cmd_pkg *pkg = (struct nd_cmd_pkg *) in_field;
return pkg->nd_size_out;
}
2015-06-09 02:27:06 +08:00
return UINT_MAX;
}
EXPORT_SYMBOL_GPL(nd_cmd_out_size);
void wait_nvdimm_bus_probe_idle(struct device *dev)
2015-05-02 01:11:27 +08:00
{
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
2015-05-02 01:11:27 +08:00
do {
if (nvdimm_bus->probe_active == 0)
break;
libnvdimm/bus: Fix wait_nvdimm_bus_probe_idle() ABBA deadlock A multithreaded namespace creation/destruction stress test currently deadlocks with the following lockup signature: INFO: task ndctl:2924 blocked for more than 122 seconds. Tainted: G OE 5.2.0-rc4+ #3382 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. ndctl D 0 2924 1176 0x00000000 Call Trace: ? __schedule+0x27e/0x780 schedule+0x30/0xb0 wait_nvdimm_bus_probe_idle+0x8a/0xd0 [libnvdimm] ? finish_wait+0x80/0x80 uuid_store+0xe6/0x2e0 [libnvdimm] kernfs_fop_write+0xf0/0x1a0 vfs_write+0xb7/0x1b0 ksys_write+0x5c/0xd0 do_syscall_64+0x60/0x240 INFO: task ndctl:2923 blocked for more than 122 seconds. Tainted: G OE 5.2.0-rc4+ #3382 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. ndctl D 0 2923 1175 0x00000000 Call Trace: ? __schedule+0x27e/0x780 ? __mutex_lock+0x489/0x910 schedule+0x30/0xb0 schedule_preempt_disabled+0x11/0x20 __mutex_lock+0x48e/0x910 ? nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] ? __lock_acquire+0x23f/0x1710 ? nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] __dax_pmem_probe+0x5e/0x210 [dax_pmem_core] ? nvdimm_bus_probe+0x1d0/0x2c0 [libnvdimm] dax_pmem_probe+0xc/0x20 [dax_pmem] nvdimm_bus_probe+0x90/0x2c0 [libnvdimm] really_probe+0xef/0x390 driver_probe_device+0xb4/0x100 In this sequence an 'nd_dax' device is being probed and trying to take the lock on its backing namespace to validate that the 'nd_dax' device indeed has exclusive access to the backing namespace. Meanwhile, another thread is trying to update the uuid property of that same backing namespace. So one thread is in the probe path trying to acquire the lock, and the other thread has acquired the lock and tries to flush the probe path. Fix this deadlock by not holding the namespace device_lock over the wait_nvdimm_bus_probe_idle() synchronization step. In turn this requires the device_lock to be held on entry to wait_nvdimm_bus_probe_idle() and subsequently dropped internally to wait_nvdimm_bus_probe_idle(). Cc: <stable@vger.kernel.org> Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation") Cc: Vishal Verma <vishal.l.verma@intel.com> Tested-by: Jane Chu <jane.chu@oracle.com> Link: https://lore.kernel.org/r/156341210094.292348.2384694131126767789.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-07-18 09:08:21 +08:00
nvdimm_bus_unlock(dev);
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
nd_device_unlock(dev);
wait_event(nvdimm_bus->wait,
2015-05-02 01:11:27 +08:00
nvdimm_bus->probe_active == 0);
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
nd_device_lock(dev);
libnvdimm/bus: Fix wait_nvdimm_bus_probe_idle() ABBA deadlock A multithreaded namespace creation/destruction stress test currently deadlocks with the following lockup signature: INFO: task ndctl:2924 blocked for more than 122 seconds. Tainted: G OE 5.2.0-rc4+ #3382 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. ndctl D 0 2924 1176 0x00000000 Call Trace: ? __schedule+0x27e/0x780 schedule+0x30/0xb0 wait_nvdimm_bus_probe_idle+0x8a/0xd0 [libnvdimm] ? finish_wait+0x80/0x80 uuid_store+0xe6/0x2e0 [libnvdimm] kernfs_fop_write+0xf0/0x1a0 vfs_write+0xb7/0x1b0 ksys_write+0x5c/0xd0 do_syscall_64+0x60/0x240 INFO: task ndctl:2923 blocked for more than 122 seconds. Tainted: G OE 5.2.0-rc4+ #3382 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. ndctl D 0 2923 1175 0x00000000 Call Trace: ? __schedule+0x27e/0x780 ? __mutex_lock+0x489/0x910 schedule+0x30/0xb0 schedule_preempt_disabled+0x11/0x20 __mutex_lock+0x48e/0x910 ? nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] ? __lock_acquire+0x23f/0x1710 ? nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] __dax_pmem_probe+0x5e/0x210 [dax_pmem_core] ? nvdimm_bus_probe+0x1d0/0x2c0 [libnvdimm] dax_pmem_probe+0xc/0x20 [dax_pmem] nvdimm_bus_probe+0x90/0x2c0 [libnvdimm] really_probe+0xef/0x390 driver_probe_device+0xb4/0x100 In this sequence an 'nd_dax' device is being probed and trying to take the lock on its backing namespace to validate that the 'nd_dax' device indeed has exclusive access to the backing namespace. Meanwhile, another thread is trying to update the uuid property of that same backing namespace. So one thread is in the probe path trying to acquire the lock, and the other thread has acquired the lock and tries to flush the probe path. Fix this deadlock by not holding the namespace device_lock over the wait_nvdimm_bus_probe_idle() synchronization step. In turn this requires the device_lock to be held on entry to wait_nvdimm_bus_probe_idle() and subsequently dropped internally to wait_nvdimm_bus_probe_idle(). Cc: <stable@vger.kernel.org> Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation") Cc: Vishal Verma <vishal.l.verma@intel.com> Tested-by: Jane Chu <jane.chu@oracle.com> Link: https://lore.kernel.org/r/156341210094.292348.2384694131126767789.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-07-18 09:08:21 +08:00
nvdimm_bus_lock(dev);
2015-05-02 01:11:27 +08:00
} while (true);
}
static int nd_pmem_forget_poison_check(struct device *dev, void *data)
{
struct nd_cmd_clear_error *clear_err =
(struct nd_cmd_clear_error *)data;
struct nd_btt *nd_btt = is_nd_btt(dev) ? to_nd_btt(dev) : NULL;
struct nd_pfn *nd_pfn = is_nd_pfn(dev) ? to_nd_pfn(dev) : NULL;
struct nd_dax *nd_dax = is_nd_dax(dev) ? to_nd_dax(dev) : NULL;
struct nd_namespace_common *ndns = NULL;
struct nd_namespace_io *nsio;
resource_size_t offset = 0, end_trunc = 0, start, end, pstart, pend;
if (nd_dax || !dev->driver)
return 0;
start = clear_err->address;
end = clear_err->address + clear_err->cleared - 1;
if (nd_btt || nd_pfn || nd_dax) {
if (nd_btt)
ndns = nd_btt->ndns;
else if (nd_pfn)
ndns = nd_pfn->ndns;
else if (nd_dax)
ndns = nd_dax->nd_pfn.ndns;
if (!ndns)
return 0;
} else
ndns = to_ndns(dev);
nsio = to_nd_namespace_io(&ndns->dev);
pstart = nsio->res.start + offset;
pend = nsio->res.end - end_trunc;
if ((pstart >= start) && (pend <= end))
return -EBUSY;
return 0;
}
static int nd_ns_forget_poison_check(struct device *dev, void *data)
{
return device_for_each_child(dev, data, nd_pmem_forget_poison_check);
}
2015-05-02 01:11:27 +08:00
/* set_config requires an idle interleave set */
static int nd_cmd_clear_to_send(struct nvdimm_bus *nvdimm_bus,
struct nvdimm *nvdimm, unsigned int cmd, void *data)
2015-05-02 01:11:27 +08:00
{
struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
/* ask the bus provider if it would like to block this request */
if (nd_desc->clear_to_send) {
int rc = nd_desc->clear_to_send(nd_desc, nvdimm, cmd, data);
if (rc)
return rc;
}
2015-05-02 01:11:27 +08:00
/* require clear error to go through the pmem driver */
if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR)
return device_for_each_child(&nvdimm_bus->dev, data,
nd_ns_forget_poison_check);
2015-05-02 01:11:27 +08:00
if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA)
return 0;
/* prevent label manipulation while the kernel owns label updates */
wait_nvdimm_bus_probe_idle(&nvdimm_bus->dev);
2015-05-02 01:11:27 +08:00
if (atomic_read(&nvdimm->busy))
return -EBUSY;
return 0;
}
2015-06-09 02:27:06 +08:00
static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
int read_only, unsigned int ioctl_cmd, unsigned long arg)
{
struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
const struct nd_cmd_desc *desc = NULL;
unsigned int cmd = _IOC_NR(ioctl_cmd);
struct device *dev = &nvdimm_bus->dev;
void __user *p = (void __user *) arg;
char *out_env = NULL, *in_env = NULL;
2015-06-09 02:27:06 +08:00
const char *cmd_name, *dimm_name;
u32 in_len = 0, out_len = 0;
unsigned int func = cmd;
unsigned long cmd_mask;
struct nd_cmd_pkg pkg;
int rc, i, cmd_rc;
void *buf = NULL;
u64 buf_len = 0;
2015-06-09 02:27:06 +08:00
if (nvdimm) {
desc = nd_cmd_dimm_desc(cmd);
cmd_name = nvdimm_cmd_name(cmd);
cmd_mask = nvdimm->cmd_mask;
2015-06-09 02:27:06 +08:00
dimm_name = dev_name(&nvdimm->dev);
} else {
desc = nd_cmd_bus_desc(cmd);
cmd_name = nvdimm_bus_cmd_name(cmd);
cmd_mask = nd_desc->cmd_mask;
2015-06-09 02:27:06 +08:00
dimm_name = "bus";
}
nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism There are currently 4 known similar but incompatible definitions of the command sets that can be sent to an NVDIMM through ACPI. It is also clear that future platform generations (ACPI or not) will continue to revise and extend the DIMM command set as new devices and use cases arrive. It is obviously untenable to continue to proliferate divergence of these command definitions, and to that end a standardization process has begun to provide for a unified specification. However, that leaves a problem about what to do with this first generation where vendors are already shipping divergence. The Linux kernel can support these initial diverged platforms without giving platform-firmware free reign to continue to diverge and compound kernel maintenance overhead. The kernel implementation can encourage standardization in two ways: 1/ Require that any function code that userspace wants to send be explicitly white-listed in the implementation. For ACPI this means function codes marked as supported by acpi_check_dsm() may only be invoked if they appear in the white-list. A function must be publicly documented before it is added to the white-list. 2/ The above restrictions can be trivially bypassed by using the "vendor-specific" payload command. However, since vendor-specific commands are by definition not publicly documented and have the potential to corrupt the kernel's view of the dimm state, we provide a toggle to disable vendor-specific operations. Enabling undefined behavior is a policy decision that can be made by the platform owner and encourages firmware implementations to choose public over private command implementations. Based on an initial patch from Jerry Hoemann Cc: Jerry Hoemann <jerry.hoemann@hpe.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-29 07:23:43 +08:00
if (cmd == ND_CMD_CALL) {
if (copy_from_user(&pkg, p, sizeof(pkg)))
return -EFAULT;
}
2015-06-09 02:27:06 +08:00
if (!desc || (desc->out_num + desc->in_num == 0) ||
!test_bit(cmd, &cmd_mask))
2015-06-09 02:27:06 +08:00
return -ENOTTY;
/* fail write commands (when read-only) */
if (read_only)
switch (cmd) {
case ND_CMD_VENDOR:
case ND_CMD_SET_CONFIG_DATA:
case ND_CMD_ARS_START:
case ND_CMD_CLEAR_ERROR:
nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism There are currently 4 known similar but incompatible definitions of the command sets that can be sent to an NVDIMM through ACPI. It is also clear that future platform generations (ACPI or not) will continue to revise and extend the DIMM command set as new devices and use cases arrive. It is obviously untenable to continue to proliferate divergence of these command definitions, and to that end a standardization process has begun to provide for a unified specification. However, that leaves a problem about what to do with this first generation where vendors are already shipping divergence. The Linux kernel can support these initial diverged platforms without giving platform-firmware free reign to continue to diverge and compound kernel maintenance overhead. The kernel implementation can encourage standardization in two ways: 1/ Require that any function code that userspace wants to send be explicitly white-listed in the implementation. For ACPI this means function codes marked as supported by acpi_check_dsm() may only be invoked if they appear in the white-list. A function must be publicly documented before it is added to the white-list. 2/ The above restrictions can be trivially bypassed by using the "vendor-specific" payload command. However, since vendor-specific commands are by definition not publicly documented and have the potential to corrupt the kernel's view of the dimm state, we provide a toggle to disable vendor-specific operations. Enabling undefined behavior is a policy decision that can be made by the platform owner and encourages firmware implementations to choose public over private command implementations. Based on an initial patch from Jerry Hoemann Cc: Jerry Hoemann <jerry.hoemann@hpe.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-29 07:23:43 +08:00
case ND_CMD_CALL:
libnvdimm/bus: Fix wait_nvdimm_bus_probe_idle() ABBA deadlock A multithreaded namespace creation/destruction stress test currently deadlocks with the following lockup signature: INFO: task ndctl:2924 blocked for more than 122 seconds. Tainted: G OE 5.2.0-rc4+ #3382 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. ndctl D 0 2924 1176 0x00000000 Call Trace: ? __schedule+0x27e/0x780 schedule+0x30/0xb0 wait_nvdimm_bus_probe_idle+0x8a/0xd0 [libnvdimm] ? finish_wait+0x80/0x80 uuid_store+0xe6/0x2e0 [libnvdimm] kernfs_fop_write+0xf0/0x1a0 vfs_write+0xb7/0x1b0 ksys_write+0x5c/0xd0 do_syscall_64+0x60/0x240 INFO: task ndctl:2923 blocked for more than 122 seconds. Tainted: G OE 5.2.0-rc4+ #3382 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. ndctl D 0 2923 1175 0x00000000 Call Trace: ? __schedule+0x27e/0x780 ? __mutex_lock+0x489/0x910 schedule+0x30/0xb0 schedule_preempt_disabled+0x11/0x20 __mutex_lock+0x48e/0x910 ? nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] ? __lock_acquire+0x23f/0x1710 ? nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] __dax_pmem_probe+0x5e/0x210 [dax_pmem_core] ? nvdimm_bus_probe+0x1d0/0x2c0 [libnvdimm] dax_pmem_probe+0xc/0x20 [dax_pmem] nvdimm_bus_probe+0x90/0x2c0 [libnvdimm] really_probe+0xef/0x390 driver_probe_device+0xb4/0x100 In this sequence an 'nd_dax' device is being probed and trying to take the lock on its backing namespace to validate that the 'nd_dax' device indeed has exclusive access to the backing namespace. Meanwhile, another thread is trying to update the uuid property of that same backing namespace. So one thread is in the probe path trying to acquire the lock, and the other thread has acquired the lock and tries to flush the probe path. Fix this deadlock by not holding the namespace device_lock over the wait_nvdimm_bus_probe_idle() synchronization step. In turn this requires the device_lock to be held on entry to wait_nvdimm_bus_probe_idle() and subsequently dropped internally to wait_nvdimm_bus_probe_idle(). Cc: <stable@vger.kernel.org> Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation") Cc: Vishal Verma <vishal.l.verma@intel.com> Tested-by: Jane Chu <jane.chu@oracle.com> Link: https://lore.kernel.org/r/156341210094.292348.2384694131126767789.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-07-18 09:08:21 +08:00
dev_dbg(dev, "'%s' command while read-only.\n",
2015-06-09 02:27:06 +08:00
nvdimm ? nvdimm_cmd_name(cmd)
: nvdimm_bus_cmd_name(cmd));
return -EPERM;
default:
break;
}
/* process an input envelope */
in_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL);
if (!in_env)
return -ENOMEM;
2015-06-09 02:27:06 +08:00
for (i = 0; i < desc->in_num; i++) {
u32 in_size, copy;
in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
if (in_size == UINT_MAX) {
dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
__func__, dimm_name, cmd_name, i);
rc = -ENXIO;
goto out;
2015-06-09 02:27:06 +08:00
}
if (in_len < ND_CMD_MAX_ENVELOPE)
copy = min_t(u32, ND_CMD_MAX_ENVELOPE - in_len, in_size);
2015-06-09 02:27:06 +08:00
else
copy = 0;
if (copy && copy_from_user(&in_env[in_len], p + in_len, copy)) {
rc = -EFAULT;
goto out;
}
2015-06-09 02:27:06 +08:00
in_len += in_size;
}
nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism There are currently 4 known similar but incompatible definitions of the command sets that can be sent to an NVDIMM through ACPI. It is also clear that future platform generations (ACPI or not) will continue to revise and extend the DIMM command set as new devices and use cases arrive. It is obviously untenable to continue to proliferate divergence of these command definitions, and to that end a standardization process has begun to provide for a unified specification. However, that leaves a problem about what to do with this first generation where vendors are already shipping divergence. The Linux kernel can support these initial diverged platforms without giving platform-firmware free reign to continue to diverge and compound kernel maintenance overhead. The kernel implementation can encourage standardization in two ways: 1/ Require that any function code that userspace wants to send be explicitly white-listed in the implementation. For ACPI this means function codes marked as supported by acpi_check_dsm() may only be invoked if they appear in the white-list. A function must be publicly documented before it is added to the white-list. 2/ The above restrictions can be trivially bypassed by using the "vendor-specific" payload command. However, since vendor-specific commands are by definition not publicly documented and have the potential to corrupt the kernel's view of the dimm state, we provide a toggle to disable vendor-specific operations. Enabling undefined behavior is a policy decision that can be made by the platform owner and encourages firmware implementations to choose public over private command implementations. Based on an initial patch from Jerry Hoemann Cc: Jerry Hoemann <jerry.hoemann@hpe.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-29 07:23:43 +08:00
if (cmd == ND_CMD_CALL) {
func = pkg.nd_command;
dev_dbg(dev, "%s, idx: %llu, in: %u, out: %u, len %llu\n",
dimm_name, pkg.nd_command,
nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism There are currently 4 known similar but incompatible definitions of the command sets that can be sent to an NVDIMM through ACPI. It is also clear that future platform generations (ACPI or not) will continue to revise and extend the DIMM command set as new devices and use cases arrive. It is obviously untenable to continue to proliferate divergence of these command definitions, and to that end a standardization process has begun to provide for a unified specification. However, that leaves a problem about what to do with this first generation where vendors are already shipping divergence. The Linux kernel can support these initial diverged platforms without giving platform-firmware free reign to continue to diverge and compound kernel maintenance overhead. The kernel implementation can encourage standardization in two ways: 1/ Require that any function code that userspace wants to send be explicitly white-listed in the implementation. For ACPI this means function codes marked as supported by acpi_check_dsm() may only be invoked if they appear in the white-list. A function must be publicly documented before it is added to the white-list. 2/ The above restrictions can be trivially bypassed by using the "vendor-specific" payload command. However, since vendor-specific commands are by definition not publicly documented and have the potential to corrupt the kernel's view of the dimm state, we provide a toggle to disable vendor-specific operations. Enabling undefined behavior is a policy decision that can be made by the platform owner and encourages firmware implementations to choose public over private command implementations. Based on an initial patch from Jerry Hoemann Cc: Jerry Hoemann <jerry.hoemann@hpe.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-29 07:23:43 +08:00
in_len, out_len, buf_len);
}
2015-06-09 02:27:06 +08:00
/* process an output envelope */
out_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL);
if (!out_env) {
rc = -ENOMEM;
goto out;
}
2015-06-09 02:27:06 +08:00
for (i = 0; i < desc->out_num; i++) {
u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
acpi, nfit, libnvdimm: fix / harden ars_status output length handling Given ambiguities in the ACPI 6.1 definition of the "Output (Size)" field of the ARS (Address Range Scrub) Status command, a firmware implementation may in practice return 0, 4, or 8 to indicate that there is no output payload to process. The specification states "Size of Output Buffer in bytes, including this field.". However, 'Output Buffer' is also the name of the entire payload, and earlier in the specification it states "Max Query ARS Status Output Buffer Size: Maximum size of buffer (including the Status and Extended Status fields)". Without this fix if the BIOS happens to return 0 it causes memory corruption as evidenced by this result from the acpi_nfit_ctl() unit test. ars_status00000000: 00020000 00000000 ........ BUG: stack guard page was hit at ffffc90001750000 (stack is ffffc9000174c000..ffffc9000174ffff) kernel stack overflow (page fault): 0000 [#1] SMP DEBUG_PAGEALLOC task: ffff8803332d2ec0 task.stack: ffffc9000174c000 RIP: 0010:[<ffffffff814cfe72>] [<ffffffff814cfe72>] __memcpy+0x12/0x20 RSP: 0018:ffffc9000174f9a8 EFLAGS: 00010246 RAX: ffffc9000174fab8 RBX: 0000000000000000 RCX: 000000001fffff56 RDX: 0000000000000000 RSI: ffff8803231f5a08 RDI: ffffc90001750000 RBP: ffffc9000174fa88 R08: ffffc9000174fab0 R09: ffff8803231f54b8 R10: 0000000000000008 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000003 R15: ffff8803231f54a0 FS: 00007f3a611af640(0000) GS:ffff88033ed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90001750000 CR3: 0000000325b20000 CR4: 00000000000406e0 Stack: ffffffffa00bc60d 0000000000000008 ffffc90000000001 ffffc9000174faac 0000000000000292 ffffffffa00c24e4 ffffffffa00c2914 0000000000000000 0000000000000000 ffffffff00000003 ffff880331ae8ad0 0000000800000246 Call Trace: [<ffffffffa00bc60d>] ? acpi_nfit_ctl+0x49d/0x750 [nfit] [<ffffffffa01f4fe0>] nfit_test_probe+0x670/0xb1b [nfit_test] Cc: <stable@vger.kernel.org> Fixes: 747ffe11b440 ("libnvdimm, tools/testing/nvdimm: fix 'ars_status' output buffer sizing") Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-12-07 01:10:12 +08:00
(u32 *) in_env, (u32 *) out_env, 0);
2015-06-09 02:27:06 +08:00
u32 copy;
if (out_size == UINT_MAX) {
dev_dbg(dev, "%s unknown output size cmd: %s field: %d\n",
dimm_name, cmd_name, i);
rc = -EFAULT;
goto out;
2015-06-09 02:27:06 +08:00
}
if (out_len < ND_CMD_MAX_ENVELOPE)
copy = min_t(u32, ND_CMD_MAX_ENVELOPE - out_len, out_size);
2015-06-09 02:27:06 +08:00
else
copy = 0;
if (copy && copy_from_user(&out_env[out_len],
p + in_len + out_len, copy)) {
rc = -EFAULT;
goto out;
}
2015-06-09 02:27:06 +08:00
out_len += out_size;
}
buf_len = (u64) out_len + (u64) in_len;
2015-06-09 02:27:06 +08:00
if (buf_len > ND_IOCTL_MAX_BUFLEN) {
dev_dbg(dev, "%s cmd: %s buf_len: %llu > %d\n", dimm_name,
cmd_name, buf_len, ND_IOCTL_MAX_BUFLEN);
rc = -EINVAL;
goto out;
2015-06-09 02:27:06 +08:00
}
buf = vmalloc(buf_len);
if (!buf) {
rc = -ENOMEM;
goto out;
}
2015-06-09 02:27:06 +08:00
if (copy_from_user(buf, p, buf_len)) {
rc = -EFAULT;
goto out;
}
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
nd_device_lock(dev);
libnvdimm/bus: Fix wait_nvdimm_bus_probe_idle() ABBA deadlock A multithreaded namespace creation/destruction stress test currently deadlocks with the following lockup signature: INFO: task ndctl:2924 blocked for more than 122 seconds. Tainted: G OE 5.2.0-rc4+ #3382 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. ndctl D 0 2924 1176 0x00000000 Call Trace: ? __schedule+0x27e/0x780 schedule+0x30/0xb0 wait_nvdimm_bus_probe_idle+0x8a/0xd0 [libnvdimm] ? finish_wait+0x80/0x80 uuid_store+0xe6/0x2e0 [libnvdimm] kernfs_fop_write+0xf0/0x1a0 vfs_write+0xb7/0x1b0 ksys_write+0x5c/0xd0 do_syscall_64+0x60/0x240 INFO: task ndctl:2923 blocked for more than 122 seconds. Tainted: G OE 5.2.0-rc4+ #3382 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. ndctl D 0 2923 1175 0x00000000 Call Trace: ? __schedule+0x27e/0x780 ? __mutex_lock+0x489/0x910 schedule+0x30/0xb0 schedule_preempt_disabled+0x11/0x20 __mutex_lock+0x48e/0x910 ? nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] ? __lock_acquire+0x23f/0x1710 ? nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] __dax_pmem_probe+0x5e/0x210 [dax_pmem_core] ? nvdimm_bus_probe+0x1d0/0x2c0 [libnvdimm] dax_pmem_probe+0xc/0x20 [dax_pmem] nvdimm_bus_probe+0x90/0x2c0 [libnvdimm] really_probe+0xef/0x390 driver_probe_device+0xb4/0x100 In this sequence an 'nd_dax' device is being probed and trying to take the lock on its backing namespace to validate that the 'nd_dax' device indeed has exclusive access to the backing namespace. Meanwhile, another thread is trying to update the uuid property of that same backing namespace. So one thread is in the probe path trying to acquire the lock, and the other thread has acquired the lock and tries to flush the probe path. Fix this deadlock by not holding the namespace device_lock over the wait_nvdimm_bus_probe_idle() synchronization step. In turn this requires the device_lock to be held on entry to wait_nvdimm_bus_probe_idle() and subsequently dropped internally to wait_nvdimm_bus_probe_idle(). Cc: <stable@vger.kernel.org> Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation") Cc: Vishal Verma <vishal.l.verma@intel.com> Tested-by: Jane Chu <jane.chu@oracle.com> Link: https://lore.kernel.org/r/156341210094.292348.2384694131126767789.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-07-18 09:08:21 +08:00
nvdimm_bus_lock(dev);
rc = nd_cmd_clear_to_send(nvdimm_bus, nvdimm, func, buf);
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if (rc)
goto out_unlock;
rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, &cmd_rc);
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if (rc < 0)
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goto out_unlock;
if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR && cmd_rc >= 0) {
struct nd_cmd_clear_error *clear_err = buf;
nvdimm_account_cleared_poison(nvdimm_bus, clear_err->address,
clear_err->cleared);
}
libnvdimm: fix reconfig_mutex, mmap_sem, and jbd2_handle lockdep splat Holding the reconfig_mutex over a potential userspace fault sets up a lockdep dependency chain between filesystem-DAX and the libnvdimm ioctl path. Move the user access outside of the lock. [ INFO: possible circular locking dependency detected ] 4.11.0-rc3+ #13 Tainted: G W O ------------------------------------------------------- fallocate/16656 is trying to acquire lock: (&nvdimm_bus->reconfig_mutex){+.+.+.}, at: [<ffffffffa00080b1>] nvdimm_bus_lock+0x21/0x30 [libnvdimm] but task is already holding lock: (jbd2_handle){++++..}, at: [<ffffffff813b4944>] start_this_handle+0x104/0x460 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (jbd2_handle){++++..}: lock_acquire+0xbd/0x200 start_this_handle+0x16a/0x460 jbd2__journal_start+0xe9/0x2d0 __ext4_journal_start_sb+0x89/0x1c0 ext4_dirty_inode+0x32/0x70 __mark_inode_dirty+0x235/0x670 generic_update_time+0x87/0xd0 touch_atime+0xa9/0xd0 ext4_file_mmap+0x90/0xb0 mmap_region+0x370/0x5b0 do_mmap+0x415/0x4f0 vm_mmap_pgoff+0xd7/0x120 SyS_mmap_pgoff+0x1c5/0x290 SyS_mmap+0x22/0x30 entry_SYSCALL_64_fastpath+0x1f/0xc2 -> #1 (&mm->mmap_sem){++++++}: lock_acquire+0xbd/0x200 __might_fault+0x70/0xa0 __nd_ioctl+0x683/0x720 [libnvdimm] nvdimm_ioctl+0x8b/0xe0 [libnvdimm] do_vfs_ioctl+0xa8/0x740 SyS_ioctl+0x79/0x90 do_syscall_64+0x6c/0x200 return_from_SYSCALL_64+0x0/0x7a -> #0 (&nvdimm_bus->reconfig_mutex){+.+.+.}: __lock_acquire+0x16b6/0x1730 lock_acquire+0xbd/0x200 __mutex_lock+0x88/0x9b0 mutex_lock_nested+0x1b/0x20 nvdimm_bus_lock+0x21/0x30 [libnvdimm] nvdimm_forget_poison+0x25/0x50 [libnvdimm] nvdimm_clear_poison+0x106/0x140 [libnvdimm] pmem_do_bvec+0x1c2/0x2b0 [nd_pmem] pmem_make_request+0xf9/0x270 [nd_pmem] generic_make_request+0x118/0x3b0 submit_bio+0x75/0x150 Cc: <stable@vger.kernel.org> Fixes: 62232e45f4a2 ("libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devices") Cc: Dave Jiang <dave.jiang@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-08 00:47:24 +08:00
2015-06-09 02:27:06 +08:00
if (copy_to_user(p, buf, buf_len))
rc = -EFAULT;
libnvdimm: fix reconfig_mutex, mmap_sem, and jbd2_handle lockdep splat Holding the reconfig_mutex over a potential userspace fault sets up a lockdep dependency chain between filesystem-DAX and the libnvdimm ioctl path. Move the user access outside of the lock. [ INFO: possible circular locking dependency detected ] 4.11.0-rc3+ #13 Tainted: G W O ------------------------------------------------------- fallocate/16656 is trying to acquire lock: (&nvdimm_bus->reconfig_mutex){+.+.+.}, at: [<ffffffffa00080b1>] nvdimm_bus_lock+0x21/0x30 [libnvdimm] but task is already holding lock: (jbd2_handle){++++..}, at: [<ffffffff813b4944>] start_this_handle+0x104/0x460 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (jbd2_handle){++++..}: lock_acquire+0xbd/0x200 start_this_handle+0x16a/0x460 jbd2__journal_start+0xe9/0x2d0 __ext4_journal_start_sb+0x89/0x1c0 ext4_dirty_inode+0x32/0x70 __mark_inode_dirty+0x235/0x670 generic_update_time+0x87/0xd0 touch_atime+0xa9/0xd0 ext4_file_mmap+0x90/0xb0 mmap_region+0x370/0x5b0 do_mmap+0x415/0x4f0 vm_mmap_pgoff+0xd7/0x120 SyS_mmap_pgoff+0x1c5/0x290 SyS_mmap+0x22/0x30 entry_SYSCALL_64_fastpath+0x1f/0xc2 -> #1 (&mm->mmap_sem){++++++}: lock_acquire+0xbd/0x200 __might_fault+0x70/0xa0 __nd_ioctl+0x683/0x720 [libnvdimm] nvdimm_ioctl+0x8b/0xe0 [libnvdimm] do_vfs_ioctl+0xa8/0x740 SyS_ioctl+0x79/0x90 do_syscall_64+0x6c/0x200 return_from_SYSCALL_64+0x0/0x7a -> #0 (&nvdimm_bus->reconfig_mutex){+.+.+.}: __lock_acquire+0x16b6/0x1730 lock_acquire+0xbd/0x200 __mutex_lock+0x88/0x9b0 mutex_lock_nested+0x1b/0x20 nvdimm_bus_lock+0x21/0x30 [libnvdimm] nvdimm_forget_poison+0x25/0x50 [libnvdimm] nvdimm_clear_poison+0x106/0x140 [libnvdimm] pmem_do_bvec+0x1c2/0x2b0 [nd_pmem] pmem_make_request+0xf9/0x270 [nd_pmem] generic_make_request+0x118/0x3b0 submit_bio+0x75/0x150 Cc: <stable@vger.kernel.org> Fixes: 62232e45f4a2 ("libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devices") Cc: Dave Jiang <dave.jiang@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-08 00:47:24 +08:00
out_unlock:
libnvdimm/bus: Fix wait_nvdimm_bus_probe_idle() ABBA deadlock A multithreaded namespace creation/destruction stress test currently deadlocks with the following lockup signature: INFO: task ndctl:2924 blocked for more than 122 seconds. Tainted: G OE 5.2.0-rc4+ #3382 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. ndctl D 0 2924 1176 0x00000000 Call Trace: ? __schedule+0x27e/0x780 schedule+0x30/0xb0 wait_nvdimm_bus_probe_idle+0x8a/0xd0 [libnvdimm] ? finish_wait+0x80/0x80 uuid_store+0xe6/0x2e0 [libnvdimm] kernfs_fop_write+0xf0/0x1a0 vfs_write+0xb7/0x1b0 ksys_write+0x5c/0xd0 do_syscall_64+0x60/0x240 INFO: task ndctl:2923 blocked for more than 122 seconds. Tainted: G OE 5.2.0-rc4+ #3382 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. ndctl D 0 2923 1175 0x00000000 Call Trace: ? __schedule+0x27e/0x780 ? __mutex_lock+0x489/0x910 schedule+0x30/0xb0 schedule_preempt_disabled+0x11/0x20 __mutex_lock+0x48e/0x910 ? nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] ? __lock_acquire+0x23f/0x1710 ? nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] nvdimm_namespace_common_probe+0x95/0x4d0 [libnvdimm] __dax_pmem_probe+0x5e/0x210 [dax_pmem_core] ? nvdimm_bus_probe+0x1d0/0x2c0 [libnvdimm] dax_pmem_probe+0xc/0x20 [dax_pmem] nvdimm_bus_probe+0x90/0x2c0 [libnvdimm] really_probe+0xef/0x390 driver_probe_device+0xb4/0x100 In this sequence an 'nd_dax' device is being probed and trying to take the lock on its backing namespace to validate that the 'nd_dax' device indeed has exclusive access to the backing namespace. Meanwhile, another thread is trying to update the uuid property of that same backing namespace. So one thread is in the probe path trying to acquire the lock, and the other thread has acquired the lock and tries to flush the probe path. Fix this deadlock by not holding the namespace device_lock over the wait_nvdimm_bus_probe_idle() synchronization step. In turn this requires the device_lock to be held on entry to wait_nvdimm_bus_probe_idle() and subsequently dropped internally to wait_nvdimm_bus_probe_idle(). Cc: <stable@vger.kernel.org> Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation") Cc: Vishal Verma <vishal.l.verma@intel.com> Tested-by: Jane Chu <jane.chu@oracle.com> Link: https://lore.kernel.org/r/156341210094.292348.2384694131126767789.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-07-18 09:08:21 +08:00
nvdimm_bus_unlock(dev);
driver-core, libnvdimm: Let device subsystems add local lockdep coverage For good reason, the standard device_lock() is marked lockdep_set_novalidate_class() because there is simply no sane way to describe the myriad ways the device_lock() ordered with other locks. However, that leaves subsystems that know their own local device_lock() ordering rules to find lock ordering mistakes manually. Instead, introduce an optional / additional lockdep-enabled lock that a subsystem can acquire in all the same paths that the device_lock() is acquired. A conversion of the NFIT driver and NVDIMM subsystem to a lockdep-validate device_lock() scheme is included. The debug_nvdimm_lock() implementation implements the correct lock-class and stacking order for the libnvdimm device topology hierarchy. Yes, this is a hack, but hopefully it is a useful hack for other subsystems device_lock() debug sessions. Quoting Greg: "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up using it as much as anything else, so user beware :) I don't object to it if it makes things easier for you to debug." Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 09:08:26 +08:00
nd_device_unlock(dev);
out:
kfree(in_env);
kfree(out_env);
2015-06-09 02:27:06 +08:00
vfree(buf);
return rc;
}
enum nd_ioctl_mode {
BUS_IOCTL,
DIMM_IOCTL,
};
2015-06-09 02:27:06 +08:00
static int match_dimm(struct device *dev, void *data)
{
long id = (long) data;
if (is_nvdimm(dev)) {
struct nvdimm *nvdimm = to_nvdimm(dev);
return nvdimm->id == id;
}
return 0;
}
static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
enum nd_ioctl_mode mode)
2015-06-09 02:27:06 +08:00
{
struct nvdimm_bus *nvdimm_bus, *found = NULL;
long id = (long) file->private_data;
struct nvdimm *nvdimm = NULL;
int rc, ro;
2015-06-09 02:27:06 +08:00
ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
2015-06-09 02:27:06 +08:00
mutex_lock(&nvdimm_bus_list_mutex);
list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
if (mode == DIMM_IOCTL) {
struct device *dev;
dev = device_find_child(&nvdimm_bus->dev,
file->private_data, match_dimm);
if (!dev)
continue;
nvdimm = to_nvdimm(dev);
found = nvdimm_bus;
} else if (nvdimm_bus->id == id) {
found = nvdimm_bus;
}
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if (found) {
atomic_inc(&nvdimm_bus->ioctl_active);
break;
}
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}
mutex_unlock(&nvdimm_bus_list_mutex);
if (!found)
return -ENXIO;
nvdimm_bus = found;
rc = __nd_ioctl(nvdimm_bus, nvdimm, ro, cmd, arg);
if (nvdimm)
put_device(&nvdimm->dev);
if (atomic_dec_and_test(&nvdimm_bus->ioctl_active))
wake_up(&nvdimm_bus->wait);
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return rc;
}
static long bus_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
return nd_ioctl(file, cmd, arg, BUS_IOCTL);
}
static long dimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
return nd_ioctl(file, cmd, arg, DIMM_IOCTL);
}
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static int nd_open(struct inode *inode, struct file *file)
{
long minor = iminor(inode);
file->private_data = (void *) minor;
return 0;
}
static const struct file_operations nvdimm_bus_fops = {
.owner = THIS_MODULE,
2015-06-09 02:27:06 +08:00
.open = nd_open,
.unlocked_ioctl = bus_ioctl,
.compat_ioctl = compat_ptr_ioctl,
.llseek = noop_llseek,
};
2015-06-09 02:27:06 +08:00
static const struct file_operations nvdimm_fops = {
.owner = THIS_MODULE,
.open = nd_open,
.unlocked_ioctl = dimm_ioctl,
.compat_ioctl = compat_ptr_ioctl,
2015-06-09 02:27:06 +08:00
.llseek = noop_llseek,
};
int __init nvdimm_bus_init(void)
{
int rc;
rc = bus_register(&nvdimm_bus_type);
if (rc)
return rc;
rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
if (rc < 0)
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goto err_bus_chrdev;
nvdimm_bus_major = rc;
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rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
if (rc < 0)
goto err_dimm_chrdev;
nvdimm_major = rc;
nd_class = class_create(THIS_MODULE, "nd");
if (IS_ERR(nd_class)) {
rc = PTR_ERR(nd_class);
goto err_class;
}
rc = driver_register(&nd_bus_driver.drv);
if (rc)
goto err_nd_bus;
return 0;
err_nd_bus:
class_destroy(nd_class);
err_class:
2015-06-09 02:27:06 +08:00
unregister_chrdev(nvdimm_major, "dimmctl");
err_dimm_chrdev:
unregister_chrdev(nvdimm_bus_major, "ndctl");
2015-06-09 02:27:06 +08:00
err_bus_chrdev:
bus_unregister(&nvdimm_bus_type);
return rc;
}
void nvdimm_bus_exit(void)
{
driver_unregister(&nd_bus_driver.drv);
class_destroy(nd_class);
unregister_chrdev(nvdimm_bus_major, "ndctl");
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unregister_chrdev(nvdimm_major, "dimmctl");
bus_unregister(&nvdimm_bus_type);
ida_destroy(&nd_ida);
}