2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-24 05:04:00 +08:00
linux-next/drivers/dax/pmem.c
Dan Williams bbb3be170a device-dax: fix sysfs duplicate warnings
Fix warnings of the form...

     WARNING: CPU: 10 PID: 4983 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x62/0x80
     sysfs: cannot create duplicate filename '/class/dax/dax12.0'
     Call Trace:
      dump_stack+0x63/0x86
      __warn+0xcb/0xf0
      warn_slowpath_fmt+0x5a/0x80
      ? kernfs_path_from_node+0x4f/0x60
      sysfs_warn_dup+0x62/0x80
      sysfs_do_create_link_sd.isra.2+0x97/0xb0
      sysfs_create_link+0x25/0x40
      device_add+0x266/0x630
      devm_create_dax_dev+0x2cf/0x340 [dax]
      dax_pmem_probe+0x1f5/0x26e [dax_pmem]
      nvdimm_bus_probe+0x71/0x120

...by reusing the namespace id for the device-dax instance name.

Now that we have decided that there will never by more than one
device-dax instance per libnvdimm-namespace parent device [1], we can
directly reuse the namepace ids. There are some possible follow-on
cleanups, but those are saved for a later patch to simplify the -stable
backport.

[1]: https://lists.01.org/pipermail/linux-nvdimm/2016-December/008266.html

Fixes: 98a29c39dc ("libnvdimm, namespace: allow creation of multiple pmem...")
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: <stable@vger.kernel.org>
Reported-by: Dariusz Dokupil <dariusz.dokupil@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-07-18 17:49:14 -07:00

166 lines
4.1 KiB
C

/*
* Copyright(c) 2016 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#include <linux/percpu-refcount.h>
#include <linux/memremap.h>
#include <linux/module.h>
#include <linux/pfn_t.h>
#include "../nvdimm/pfn.h"
#include "../nvdimm/nd.h"
#include "device-dax.h"
struct dax_pmem {
struct device *dev;
struct percpu_ref ref;
struct completion cmp;
};
static struct dax_pmem *to_dax_pmem(struct percpu_ref *ref)
{
return container_of(ref, struct dax_pmem, ref);
}
static void dax_pmem_percpu_release(struct percpu_ref *ref)
{
struct dax_pmem *dax_pmem = to_dax_pmem(ref);
dev_dbg(dax_pmem->dev, "%s\n", __func__);
complete(&dax_pmem->cmp);
}
static void dax_pmem_percpu_exit(void *data)
{
struct percpu_ref *ref = data;
struct dax_pmem *dax_pmem = to_dax_pmem(ref);
dev_dbg(dax_pmem->dev, "%s\n", __func__);
wait_for_completion(&dax_pmem->cmp);
percpu_ref_exit(ref);
}
static void dax_pmem_percpu_kill(void *data)
{
struct percpu_ref *ref = data;
struct dax_pmem *dax_pmem = to_dax_pmem(ref);
dev_dbg(dax_pmem->dev, "%s\n", __func__);
percpu_ref_kill(ref);
}
static int dax_pmem_probe(struct device *dev)
{
void *addr;
struct resource res;
int rc, id, region_id;
struct nd_pfn_sb *pfn_sb;
struct dev_dax *dev_dax;
struct dax_pmem *dax_pmem;
struct nd_namespace_io *nsio;
struct dax_region *dax_region;
struct nd_namespace_common *ndns;
struct nd_dax *nd_dax = to_nd_dax(dev);
struct nd_pfn *nd_pfn = &nd_dax->nd_pfn;
struct vmem_altmap __altmap, *altmap = NULL;
ndns = nvdimm_namespace_common_probe(dev);
if (IS_ERR(ndns))
return PTR_ERR(ndns);
nsio = to_nd_namespace_io(&ndns->dev);
/* parse the 'pfn' info block via ->rw_bytes */
rc = devm_nsio_enable(dev, nsio);
if (rc)
return rc;
altmap = nvdimm_setup_pfn(nd_pfn, &res, &__altmap);
if (IS_ERR(altmap))
return PTR_ERR(altmap);
devm_nsio_disable(dev, nsio);
pfn_sb = nd_pfn->pfn_sb;
if (!devm_request_mem_region(dev, nsio->res.start,
resource_size(&nsio->res),
dev_name(&ndns->dev))) {
dev_warn(dev, "could not reserve region %pR\n", &nsio->res);
return -EBUSY;
}
dax_pmem = devm_kzalloc(dev, sizeof(*dax_pmem), GFP_KERNEL);
if (!dax_pmem)
return -ENOMEM;
dax_pmem->dev = dev;
init_completion(&dax_pmem->cmp);
rc = percpu_ref_init(&dax_pmem->ref, dax_pmem_percpu_release, 0,
GFP_KERNEL);
if (rc)
return rc;
rc = devm_add_action_or_reset(dev, dax_pmem_percpu_exit,
&dax_pmem->ref);
if (rc)
return rc;
addr = devm_memremap_pages(dev, &res, &dax_pmem->ref, altmap);
if (IS_ERR(addr))
return PTR_ERR(addr);
rc = devm_add_action_or_reset(dev, dax_pmem_percpu_kill,
&dax_pmem->ref);
if (rc)
return rc;
/* adjust the dax_region resource to the start of data */
res.start += le64_to_cpu(pfn_sb->dataoff);
rc = sscanf(dev_name(&ndns->dev), "namespace%d.%d", &region_id, &id);
if (rc != 2)
return -EINVAL;
dax_region = alloc_dax_region(dev, region_id, &res,
le32_to_cpu(pfn_sb->align), addr, PFN_DEV|PFN_MAP);
if (!dax_region)
return -ENOMEM;
/* TODO: support for subdividing a dax region... */
dev_dax = devm_create_dev_dax(dax_region, id, &res, 1);
/* child dev_dax instances now own the lifetime of the dax_region */
dax_region_put(dax_region);
return PTR_ERR_OR_ZERO(dev_dax);
}
static struct nd_device_driver dax_pmem_driver = {
.probe = dax_pmem_probe,
.drv = {
.name = "dax_pmem",
},
.type = ND_DRIVER_DAX_PMEM,
};
static int __init dax_pmem_init(void)
{
return nd_driver_register(&dax_pmem_driver);
}
module_init(dax_pmem_init);
static void __exit dax_pmem_exit(void)
{
driver_unregister(&dax_pmem_driver.drv);
}
module_exit(dax_pmem_exit);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Intel Corporation");
MODULE_ALIAS_ND_DEVICE(ND_DEVICE_DAX_PMEM);