Message ID | 20190604091357.32213-3-aneesh.kumar@linux.ibm.com (mailing list archive) |
---|---|
State | Not Applicable |
Headers | show |
Series | [v3,1/6] nvdimm: Consider probe return -EOPNOTSUPP as success | expand |
Context | Check | Description |
---|---|---|
snowpatch_ozlabs/apply_patch | success | Successfully applied on branch next (a3bf9fbdad600b1e4335dd90979f8d6072e4f602) |
snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 68 lines checked |
On Tue 04-06-19 14:43:54, Aneesh Kumar K.V wrote: > 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> ... > diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c > index 00c57805cad3..e01eee9efafe 100644 > --- a/drivers/nvdimm/pfn_devs.c > +++ b/drivers/nvdimm/pfn_devs.c > @@ -467,6 +467,15 @@ 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: As we discussed with Aneesh privately, this actually means that existing NVDIMM namespaces on PPC64 will stop working due to these defaults for old superblocks. I don't think that's a good thing as upgrading kernels is going to be nightmare due to this on PPC64. So I believe we should make defaults for old superblocks such that working setups keep working without sysadmin having to touch anything. Honza
diff --git a/drivers/nvdimm/pfn.h b/drivers/nvdimm/pfn.h index 5fd29242745a..ba11738ca8a2 100644 --- a/drivers/nvdimm/pfn.h +++ b/drivers/nvdimm/pfn.h @@ -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; }; diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c index 00c57805cad3..e01eee9efafe 100644 --- a/drivers/nvdimm/pfn_devs.c +++ b/drivers/nvdimm/pfn_devs.c @@ -467,6 +467,15 @@ 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: @@ -482,6 +491,20 @@ 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 @@ -776,11 +799,13 @@ 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 | 27 ++++++++++++++++++++++++++- 2 files changed, 31 insertions(+), 3 deletions(-)