Commit b6135210 authored by Yi Yang's avatar Yi Yang Committed by Ira Weiny
Browse files

nvdimm: rectify the illogical code within nd_dax_probe() 



When nd_dax is NULL, nd_pfn is consequently NULL as well. Nevertheless,
it is inadvisable to perform pointer arithmetic or address-taking on a
NULL pointer.
Introduce the nd_dax_devinit() function to enhance the code's logic and
improve its readability.

Signed-off-by: default avatarYi Yang <yiyang13@huawei.com>
Reviewed-by: default avatarDave Jiang <dave.jiang@intel.com>
Link: https://patch.msgid.link/20241108085526.527957-1-yiyang13@huawei.com


Signed-off-by: default avatarIra Weiny <ira.weiny@intel.com>
parent f7f50742

drivers/nvdimm/dax_devs.c

+2 −2
Original line number Diff line number Diff line
@@ -106,12 +106,12 @@ int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns) 


	nvdimm_bus_lock(&ndns->dev);

	nd_dax = nd_dax_alloc(nd_region);

	nd_pfn = &nd_dax->nd_pfn;

	dax_dev = nd_pfn_devinit(nd_pfn, ndns);

	dax_dev = nd_dax_devinit(nd_dax, ndns);

	nvdimm_bus_unlock(&ndns->dev);

	if (!dax_dev)

		return -ENOMEM;

	pfn_sb = devm_kmalloc(dev, sizeof(*pfn_sb), GFP_KERNEL);

	nd_pfn = &nd_dax->nd_pfn;

	nd_pfn->pfn_sb = pfn_sb;

	rc = nd_pfn_validate(nd_pfn, DAX_SIG);

	dev_dbg(dev, "dax: %s\n", rc == 0 ? dev_name(dax_dev) : "<none>");

drivers/nvdimm/nd.h

+7 −0
Original line number Diff line number Diff line
@@ -600,6 +600,13 @@ struct nd_dax *to_nd_dax(struct device *dev); 
int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns);

bool is_nd_dax(const struct device *dev);

struct device *nd_dax_create(struct nd_region *nd_region);

static inline struct device *nd_dax_devinit(struct nd_dax *nd_dax,

					    struct nd_namespace_common *ndns)

{

	if (!nd_dax)

		return NULL;

	return nd_pfn_devinit(&nd_dax->nd_pfn, ndns);

}

#else

static inline int nd_dax_probe(struct device *dev,

		struct nd_namespace_common *ndns)