@@ -25,7 +25,7 @@
* kernel should fail to initialize that namespace.
*/
-#define PFN_MIN_VERSION 0
+#define PFN_MIN_VERSION 1
struct nd_pfn_sb {
u8 signature[PFN_SIG_LEN];
@@ -43,7 +43,10 @@ struct nd_pfn_sb {
/* minor-version-2 record the base alignment of the mapping */
__le32 align;
__le16 min_version;
- u8 padding[3998];
+ /* minor-version-3 record the page size and struct page size */
+ __le16 page_struct_size;
+ __le32 page_size;
+ u8 padding[3992];
__le64 checksum;
};
@@ -466,6 +466,15 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig)
if (__le16_to_cpu(pfn_sb->version_minor) < 2)
pfn_sb->align = 0;
+ if (__le16_to_cpu(pfn_sb->version_minor) < 3) {
+ /*
+ * For a large part we use PAGE_SIZE. But we
+ * do have some accounting code using SZ_4K.
+ */
+ pfn_sb->page_struct_size = cpu_to_le16(64);
+ pfn_sb->page_size = cpu_to_le32(SZ_4K);
+ }
+
switch (le32_to_cpu(pfn_sb->mode)) {
case PFN_MODE_RAM:
case PFN_MODE_PMEM:
@@ -481,6 +490,12 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig)
align = 1UL << ilog2(offset);
mode = le32_to_cpu(pfn_sb->mode);
+ if (le32_to_cpu(pfn_sb->page_size) != PAGE_SIZE)
+ return -EOPNOTSUPP;
+
+ if (le16_to_cpu(pfn_sb->page_struct_size) != sizeof(struct page))
+ return -EOPNOTSUPP;
+
if (!nd_pfn->uuid) {
/*
* When probing a namepace via nd_pfn_probe() the uuid
@@ -775,11 +790,13 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn)
memcpy(pfn_sb->uuid, nd_pfn->uuid, 16);
memcpy(pfn_sb->parent_uuid, nd_dev_to_uuid(&ndns->dev), 16);
pfn_sb->version_major = cpu_to_le16(1);
- pfn_sb->version_minor = cpu_to_le16(2);
+ pfn_sb->version_minor = cpu_to_le16(3);
pfn_sb->min_version = cpu_to_le16(PFN_MIN_VERSION);
pfn_sb->start_pad = cpu_to_le32(start_pad);
pfn_sb->end_trunc = cpu_to_le32(end_trunc);
pfn_sb->align = cpu_to_le32(nd_pfn->align);
+ pfn_sb->page_struct_size = cpu_to_le16(sizeof(struct page));
+ pfn_sb->page_size = cpu_to_le32(PAGE_SIZE);
checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb);
pfn_sb->checksum = cpu_to_le64(checksum);
This is needed so that we don't wrongly initialize a namespace which doesn't have enough space reserved for holding struct pages with the current kernel. We also increment PFN_MIN_VERSION to make sure that older kernel won't initialize namespace created with newer kernel. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> --- drivers/nvdimm/pfn.h | 7 +++++-- drivers/nvdimm/pfn_devs.c | 19 ++++++++++++++++++- 2 files changed, 23 insertions(+), 3 deletions(-)