diff options
author | Dan Williams <dan.j.williams@intel.com> | 2017-07-16 13:51:53 -0700 |
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committer | Dan Williams <dan.j.williams@intel.com> | 2019-01-06 21:41:57 -0800 |
commit | 730926c3b0998943654019f00296cf8e3b02277e (patch) | |
tree | 9bdff0b62f4a020427144de5b703048bfb1f7c16 /drivers/dax/pmem/compat.c | |
parent | d200781ef237a354d918ceff5cee350d88a93d42 (diff) | |
download | linux-730926c3b0998943654019f00296cf8e3b02277e.tar.bz2 |
device-dax: Add /sys/class/dax backwards compatibility
On the expectation that some environments may not upgrade libdaxctl
(userspace component that depends on the /sys/class/dax hierarchy),
provide a default / legacy dax_pmem_compat driver. The dax_pmem_compat
driver implements the original /sys/class/dax sysfs layout rather than
/sys/bus/dax. When userspace is upgraded it can blacklist this module
and switch to the dax_pmem driver going forward.
CONFIG_DEV_DAX_PMEM_COMPAT and supporting code will be deleted according
to the dax_pmem entry in Documentation/ABI/obsolete/.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dax/pmem/compat.c')
-rw-r--r-- | drivers/dax/pmem/compat.c | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/drivers/dax/pmem/compat.c b/drivers/dax/pmem/compat.c new file mode 100644 index 000000000000..d7b15e6f30c5 --- /dev/null +++ b/drivers/dax/pmem/compat.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved. */ +#include <linux/percpu-refcount.h> +#include <linux/memremap.h> +#include <linux/module.h> +#include <linux/pfn_t.h> +#include <linux/nd.h> +#include "../bus.h" + +/* we need the private definitions to implement compat suport */ +#include "../dax-private.h" + +static int dax_pmem_compat_probe(struct device *dev) +{ + struct dev_dax *dev_dax = __dax_pmem_probe(dev, DEV_DAX_CLASS); + int rc; + + if (IS_ERR(dev_dax)) + return PTR_ERR(dev_dax); + + if (!devres_open_group(&dev_dax->dev, dev_dax, GFP_KERNEL)) + return -ENOMEM; + + device_lock(&dev_dax->dev); + rc = dev_dax_probe(&dev_dax->dev); + device_unlock(&dev_dax->dev); + + devres_close_group(&dev_dax->dev, dev_dax); + if (rc) + devres_release_group(&dev_dax->dev, dev_dax); + + return rc; +} + +static int dax_pmem_compat_release(struct device *dev, void *data) +{ + device_lock(dev); + devres_release_group(dev, to_dev_dax(dev)); + device_unlock(dev); + + return 0; +} + +static int dax_pmem_compat_remove(struct device *dev) +{ + device_for_each_child(dev, NULL, dax_pmem_compat_release); + return 0; +} + +static struct nd_device_driver dax_pmem_compat_driver = { + .probe = dax_pmem_compat_probe, + .remove = dax_pmem_compat_remove, + .drv = { + .name = "dax_pmem_compat", + }, + .type = ND_DRIVER_DAX_PMEM, +}; + +static int __init dax_pmem_compat_init(void) +{ + return nd_driver_register(&dax_pmem_compat_driver); +} +module_init(dax_pmem_compat_init); + +static void __exit dax_pmem_compat_exit(void) +{ + driver_unregister(&dax_pmem_compat_driver.drv); +} +module_exit(dax_pmem_compat_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Intel Corporation"); +MODULE_ALIAS_ND_DEVICE(ND_DEVICE_DAX_PMEM); |