[PATCH v2] device-dax: Adding match parameter to select which driver to match dax devices

From: Zhenguo Yao
Date: Wed Mar 02 2022 - 22:31:55 EST


device_dax driver always match dax devices by default. The other
drivers only match devices by dax_id. There is situations which
need kmem drvier match all the dax device at boot time. So
adding a parameter to support this function.

Signed-off-by: Zhenguo Yao <yaozhenguo1@xxxxxxxxx>
---

Changes:
- v1->v2 fix build errors report by kernel test robot <lkp@xxxxxxxxx>
---

drivers/dax/device.c | 3 +++
drivers/dax/kmem.c | 4 ++++
2 files changed, 7 insertions(+)

diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index dd8222a..3d228b2 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -452,6 +452,7 @@ int dev_dax_probe(struct dev_dax *dev_dax)
}
EXPORT_SYMBOL_GPL(dev_dax_probe);

+unsigned int dax_match = 1;
static struct dax_device_driver device_dax_driver = {
.probe = dev_dax_probe,
/* all probe actions are unwound by devm, so .remove isn't necessary */
@@ -460,6 +461,7 @@ int dev_dax_probe(struct dev_dax *dev_dax)

static int __init dax_init(void)
{
+ device_dax_driver.match_always = dax_match;
return dax_driver_register(&device_dax_driver);
}

@@ -468,6 +470,7 @@ static void __exit dax_exit(void)
dax_driver_unregister(&device_dax_driver);
}

+module_param(dax_match, uint, 0644);
MODULE_AUTHOR("Intel Corporation");
MODULE_LICENSE("GPL v2");
module_init(dax_init);
diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c
index a376220..2f1fb98 100644
--- a/drivers/dax/kmem.c
+++ b/drivers/dax/kmem.c
@@ -214,9 +214,11 @@ static void dev_dax_kmem_remove(struct dev_dax *dev_dax)
}
#endif /* CONFIG_MEMORY_HOTREMOVE */

+unsigned int kmem_match;
static struct dax_device_driver device_dax_kmem_driver = {
.probe = dev_dax_kmem_probe,
.remove = dev_dax_kmem_remove,
+ .match_always = 0,
};

static int __init dax_kmem_init(void)
@@ -228,6 +230,7 @@ static int __init dax_kmem_init(void)
if (!kmem_name)
return -ENOMEM;

+ device_dax_kmem_driver.match_always = kmem_match;
rc = dax_driver_register(&device_dax_kmem_driver);
if (rc)
kfree_const(kmem_name);
@@ -241,6 +244,7 @@ static void __exit dax_kmem_exit(void)
kfree_const(kmem_name);
}

+module_param(kmem_match, uint, 0644);
MODULE_AUTHOR("Intel Corporation");
MODULE_LICENSE("GPL v2");
module_init(dax_kmem_init);
--
1.8.3.1