linux/drivers/dax/bus.h
Dan Williams 83762cb5c7 dax: Kill DEV_DAX_PMEM_COMPAT
The /sys/class/dax compatibility option has shipped in the kernel for 4
years now which should be sufficient time for tools to abandon the old
ABI in favor of the /sys/bus/dax device-model. Delete it now and see if
anyone screams.

Since this compatibility option shipped there has been more reports of
users being surprised by the compat ABI than surprised by the "new", so
the compat infrastructure has outlived its usefulness. Recall that
/sys/bus/dax device-model is required for the dax kmem driver which
allows PMEM to be used as "System RAM".

The following projects were known to have a dependency on /sys/class/dax
and have dropped their dependency as of the listed version:

- ndctl (including libndctl, daxctl, and libdaxctl): v64+
- fio: v3.13+
- pmdk: v1.5.2+

As further evidence this option is no longer needed some distributions
have already stopped enabling CONFIG_DEV_DAX_PMEM_COMPAT.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Reported-by: Vishal Verma <vishal.l.verma@intel.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Jane Chu <jane.chu@oracle.com>
Link: https://lore.kernel.org/r/163701116195.3784476.726128179293466337.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-11-24 19:21:35 -08:00

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1.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved. */
#ifndef __DAX_BUS_H__
#define __DAX_BUS_H__
#include <linux/device.h>
#include <linux/range.h>
struct dev_dax;
struct resource;
struct dax_device;
struct dax_region;
void dax_region_put(struct dax_region *dax_region);
#define IORESOURCE_DAX_STATIC (1UL << 0)
struct dax_region *alloc_dax_region(struct device *parent, int region_id,
struct range *range, int target_node, unsigned int align,
unsigned long flags);
struct dev_dax_data {
struct dax_region *dax_region;
struct dev_pagemap *pgmap;
resource_size_t size;
int id;
};
struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data);
struct dax_device_driver {
struct device_driver drv;
struct list_head ids;
int match_always;
int (*probe)(struct dev_dax *dev);
void (*remove)(struct dev_dax *dev);
};
int __dax_driver_register(struct dax_device_driver *dax_drv,
struct module *module, const char *mod_name);
#define dax_driver_register(driver) \
__dax_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
void dax_driver_unregister(struct dax_device_driver *dax_drv);
void kill_dev_dax(struct dev_dax *dev_dax);
/*
* While run_dax() is potentially a generic operation that could be
* defined in include/linux/dax.h we don't want to grow any users
* outside of drivers/dax/
*/
void run_dax(struct dax_device *dax_dev);
#define MODULE_ALIAS_DAX_DEVICE(type) \
MODULE_ALIAS("dax:t" __stringify(type) "*")
#define DAX_DEVICE_MODALIAS_FMT "dax:t%d"
#endif /* __DAX_BUS_H__ */