ACPI: NFIT: Fix flexible_array.cocci warnings

Julia and 0day report:

    Zero-length and one-element arrays are deprecated, see
    Documentation/process/deprecated.rst
    Flexible-array members should be used instead.

However, a straight conversion to flexible arrays yields:

    drivers/acpi/nfit/core.c:2276:4: error: flexible array member in a struct with no named members
    drivers/acpi/nfit/core.c:2287:4: error: flexible array member in a struct with no named members

Instead, just use plain arrays not embedded flexible arrays.

Cc: Denis Efremov <efremov@linux.com>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Julia Lawall <julia.lawall@inria.fr>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index b11b08a..8c5dde6 100644 (file)
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -2269,40 +2269,24 @@ static const struct attribute_group *acpi_nfit_region_attribute_groups[] = {
 
 /* enough info to uniquely specify an interleave set */
 struct nfit_set_info {
-       struct nfit_set_info_map {
-               u64 region_offset;
-               u32 serial_number;
-               u32 pad;
-       } mapping[0];
+       u64 region_offset;
+       u32 serial_number;
+       u32 pad;
 };
 
 struct nfit_set_info2 {
-       struct nfit_set_info_map2 {
-               u64 region_offset;
-               u32 serial_number;
-               u16 vendor_id;
-               u16 manufacturing_date;
-               u8  manufacturing_location;
-               u8  reserved[31];
-       } mapping[0];
+       u64 region_offset;
+       u32 serial_number;
+       u16 vendor_id;
+       u16 manufacturing_date;
+       u8 manufacturing_location;
+       u8 reserved[31];
 };
 
-static size_t sizeof_nfit_set_info(int num_mappings)
-{
-       return sizeof(struct nfit_set_info)
-               + num_mappings * sizeof(struct nfit_set_info_map);
-}
-
-static size_t sizeof_nfit_set_info2(int num_mappings)
-{
-       return sizeof(struct nfit_set_info2)
-               + num_mappings * sizeof(struct nfit_set_info_map2);
-}
-
 static int cmp_map_compat(const void *m0, const void *m1)
 {
-       const struct nfit_set_info_map *map0 = m0;
-       const struct nfit_set_info_map *map1 = m1;
+       const struct nfit_set_info *map0 = m0;
+       const struct nfit_set_info *map1 = m1;
 
        return memcmp(&map0->region_offset, &map1->region_offset,
                        sizeof(u64));
@@ -2310,8 +2294,8 @@ static int cmp_map_compat(const void *m0, const void *m1)
 
 static int cmp_map(const void *m0, const void *m1)
 {
-       const struct nfit_set_info_map *map0 = m0;
-       const struct nfit_set_info_map *map1 = m1;
+       const struct nfit_set_info *map0 = m0;
+       const struct nfit_set_info *map1 = m1;
 
        if (map0->region_offset < map1->region_offset)
                return -1;
@@ -2322,8 +2306,8 @@ static int cmp_map(const void *m0, const void *m1)
 
 static int cmp_map2(const void *m0, const void *m1)
 {
-       const struct nfit_set_info_map2 *map0 = m0;
-       const struct nfit_set_info_map2 *map1 = m1;
+       const struct nfit_set_info2 *map0 = m0;
+       const struct nfit_set_info2 *map1 = m1;
 
        if (map0->region_offset < map1->region_offset)
                return -1;
@@ -2361,22 +2345,22 @@ static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc,
                return -ENOMEM;
        import_guid(&nd_set->type_guid, spa->range_guid);
 
-       info = devm_kzalloc(dev, sizeof_nfit_set_info(nr), GFP_KERNEL);
+       info = devm_kcalloc(dev, nr, sizeof(*info), GFP_KERNEL);
        if (!info)
                return -ENOMEM;
 
-       info2 = devm_kzalloc(dev, sizeof_nfit_set_info2(nr), GFP_KERNEL);
+       info2 = devm_kcalloc(dev, nr, sizeof(*info2), GFP_KERNEL);
        if (!info2)
                return -ENOMEM;
 
        for (i = 0; i < nr; i++) {
                struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
-               struct nfit_set_info_map *map = &info->mapping[i];
-               struct nfit_set_info_map2 *map2 = &info2->mapping[i];
                struct nvdimm *nvdimm = mapping->nvdimm;
                struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
-               struct acpi_nfit_memory_map *memdev = memdev_from_spa(acpi_desc,
-                               spa->range_index, i);
+               struct nfit_set_info *map = &info[i];
+               struct nfit_set_info2 *map2 = &info2[i];
+               struct acpi_nfit_memory_map *memdev =
+                       memdev_from_spa(acpi_desc, spa->range_index, i);
                struct acpi_nfit_control_region *dcr = nfit_mem->dcr;
 
                if (!memdev || !nfit_mem->dcr) {
@@ -2395,23 +2379,20 @@ static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc,
        }
 
        /* v1.1 namespaces */
-       sort(&info->mapping[0], nr, sizeof(struct nfit_set_info_map),
-                       cmp_map, NULL);
-       nd_set->cookie1 = nd_fletcher64(info, sizeof_nfit_set_info(nr), 0);
+       sort(info, nr, sizeof(*info), cmp_map, NULL);
+       nd_set->cookie1 = nd_fletcher64(info, sizeof(*info) * nr, 0);
 
        /* v1.2 namespaces */
-       sort(&info2->mapping[0], nr, sizeof(struct nfit_set_info_map2),
-                       cmp_map2, NULL);
-       nd_set->cookie2 = nd_fletcher64(info2, sizeof_nfit_set_info2(nr), 0);
+       sort(info2, nr, sizeof(*info2), cmp_map2, NULL);
+       nd_set->cookie2 = nd_fletcher64(info2, sizeof(*info2) * nr, 0);
 
        /* support v1.1 namespaces created with the wrong sort order */
-       sort(&info->mapping[0], nr, sizeof(struct nfit_set_info_map),
-                       cmp_map_compat, NULL);
-       nd_set->altcookie = nd_fletcher64(info, sizeof_nfit_set_info(nr), 0);
+       sort(info, nr, sizeof(*info), cmp_map_compat, NULL);
+       nd_set->altcookie = nd_fletcher64(info, sizeof(*info) * nr, 0);
 
        /* record the result of the sort for the mapping position */
        for (i = 0; i < nr; i++) {
-               struct nfit_set_info_map2 *map2 = &info2->mapping[i];
+               struct nfit_set_info2 *map2 = &info2[i];
                int j;
 
                for (j = 0; j < nr; j++) {