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.
Signed-off-by: Aneesh Kumar K.V <aneesh.ku...@linux.ibm.com> --- drivers/nvdimm/pfn.h | 5 ++++- drivers/nvdimm/pfn_devs.c | 27 ++++++++++++++++++++++++++- 2 files changed, 30 insertions(+), 2 deletions(-) diff --git a/drivers/nvdimm/pfn.h b/drivers/nvdimm/pfn.h index 7381673b7b70..acb19517f678 100644 --- a/drivers/nvdimm/pfn.h +++ b/drivers/nvdimm/pfn.h @@ -29,7 +29,10 @@ struct nd_pfn_sb { /* minor-version-2 record the base alignment of the mapping */ __le32 align; /* minor-version-3 guarantee the padding and flags are zero */ - u8 padding[4000]; + /* minor-version-4 record the page size and struct page size */ + __le32 page_size; + __le16 page_struct_size; + u8 padding[3994]; __le64 checksum; }; diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c index 2537aa338bd0..cd722de0ae03 100644 --- a/drivers/nvdimm/pfn_devs.c +++ b/drivers/nvdimm/pfn_devs.c @@ -460,6 +460,15 @@ 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) < 4) { + /* + * 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(PAGE_SIZE); + } + switch (le32_to_cpu(pfn_sb->mode)) { case PFN_MODE_RAM: case PFN_MODE_PMEM: @@ -475,6 +484,20 @@ 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) { + dev_err(&nd_pfn->dev, + "init failed, page size mismatch %d\n", + le32_to_cpu(pfn_sb->page_size)); + return -EOPNOTSUPP; + } + + if (le16_to_cpu(pfn_sb->page_struct_size) != sizeof(struct page)) { + dev_err(&nd_pfn->dev, + "init failed, struct page size mismatch %d\n", + le16_to_cpu(pfn_sb->page_struct_size)); + return -EOPNOTSUPP; + } + if (!nd_pfn->uuid) { /* * When probing a namepace via nd_pfn_probe() the uuid @@ -723,8 +746,10 @@ 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(3); + pfn_sb->version_minor = cpu_to_le16(4); 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); -- 2.21.0 _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm