The patch titled
Subject: libnvdimm, pfn, dax: stop padding pmem namespaces to section alignment
has been added to the -mm tree. Its filename is
libnvdimm-pfn-dax-stop-padding-pmem-namespaces-to-section-alignment.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/libnvdimm-pfn-dax-stop-padding-pmem-namespaces-to-section-alignment.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/libnvdimm-pfn-dax-stop-padding-pmem-namespaces-to-section-alignment.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Dan Williams <dan.j.williams@xxxxxxxxx>
Subject: libnvdimm, pfn, dax: stop padding pmem namespaces to section alignment
Now that the mm core supports section-unaligned hotplug of ZONE_DEVICE
memory, we no longer need to add padding at pfn/dax device creation time.
The kernel will still honor padding established by older kernels.
Link: http://lkml.kernel.org/r/148486366619.19694.12717075723603032515.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Toshi Kani <toshi.kani@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/nvdimm/pfn_devs.c | 42 ++++++------------------------------
1 file changed, 7 insertions(+), 35 deletions(-)
diff -puN drivers/nvdimm/pfn_devs.c~libnvdimm-pfn-dax-stop-padding-pmem-namespaces-to-section-alignment drivers/nvdimm/pfn_devs.c
--- a/drivers/nvdimm/pfn_devs.c~libnvdimm-pfn-dax-stop-padding-pmem-namespaces-to-section-alignment
+++ a/drivers/nvdimm/pfn_devs.c
@@ -538,7 +538,7 @@ static struct vmem_altmap *__nvdimm_setu
nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns);
altmap = NULL;
} else if (nd_pfn->mode == PFN_MODE_PMEM) {
- nd_pfn->npfns = (resource_size(res) - offset) / PAGE_SIZE;
+ nd_pfn->npfns = PHYS_PFN((resource_size(res) - offset));
if (le64_to_cpu(nd_pfn->pfn_sb->npfns) > nd_pfn->npfns)
dev_info(&nd_pfn->dev,
"number of pfns truncated from %lld to %ld\n",
@@ -557,7 +557,6 @@ static int nd_pfn_init(struct nd_pfn *nd
{
u32 dax_label_reserve = is_nd_dax(&nd_pfn->dev) ? SZ_128K : 0;
struct nd_namespace_common *ndns = nd_pfn->ndns;
- u32 start_pad = 0, end_trunc = 0;
resource_size_t start, size;
struct nd_namespace_io *nsio;
struct nd_region *nd_region;
@@ -590,42 +589,16 @@ static int nd_pfn_init(struct nd_pfn *nd
return -ENXIO;
}
- memset(pfn_sb, 0, sizeof(*pfn_sb));
-
- /*
- * Check if pmem collides with 'System RAM' when section aligned and
- * trim it accordingly
- */
- nsio = to_nd_namespace_io(&ndns->dev);
- start = PHYS_SECTION_ALIGN_DOWN(nsio->res.start);
- size = resource_size(&nsio->res);
- if (region_intersects(start, size, IORESOURCE_SYSTEM_RAM,
- IORES_DESC_NONE) == REGION_MIXED) {
- start = nsio->res.start;
- start_pad = PHYS_SECTION_ALIGN_UP(start) - start;
- }
-
- start = nsio->res.start;
- size = PHYS_SECTION_ALIGN_UP(start + size) - start;
- if (region_intersects(start, size, IORESOURCE_SYSTEM_RAM,
- IORES_DESC_NONE) == REGION_MIXED) {
- size = resource_size(&nsio->res);
- end_trunc = start + size - PHYS_SECTION_ALIGN_DOWN(start + size);
- }
-
- if (start_pad + end_trunc)
- dev_info(&nd_pfn->dev, "%s section collision, truncate %d bytes\n",
- dev_name(&ndns->dev), start_pad + end_trunc);
-
/*
* Note, we use 64 here for the standard size of struct page,
* debugging options may cause it to be larger in which case the
* implementation will limit the pfns advertised through
* ->direct_access() to those that are included in the memmap.
*/
- start += start_pad;
+ nsio = to_nd_namespace_io(&ndns->dev);
+ start = nsio->res.start;
size = resource_size(&nsio->res);
- npfns = (size - start_pad - end_trunc - SZ_8K) / SZ_4K;
+ npfns = PHYS_PFN(size - SZ_8K);
if (nd_pfn->mode == PFN_MODE_PMEM) {
unsigned long memmap_size;
@@ -642,13 +615,14 @@ static int nd_pfn_init(struct nd_pfn *nd
else
return -ENXIO;
- if (offset + start_pad + end_trunc >= size) {
+ if (offset >= size) {
dev_err(&nd_pfn->dev, "%s unable to satisfy requested alignment\n",
dev_name(&ndns->dev));
return -ENXIO;
}
- npfns = (size - offset - start_pad - end_trunc) / SZ_4K;
+ memset(pfn_sb, 0, sizeof(*pfn_sb));
+ npfns = PHYS_PFN(size - offset);
pfn_sb->mode = cpu_to_le32(nd_pfn->mode);
pfn_sb->dataoff = cpu_to_le64(offset);
pfn_sb->npfns = cpu_to_le64(npfns);
@@ -657,8 +631,6 @@ static int nd_pfn_init(struct nd_pfn *nd
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->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);
checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb);
pfn_sb->checksum = cpu_to_le64(checksum);
_
Patches currently in -mm which might be from dan.j.williams@xxxxxxxxx are
mm-fix-type-width-of-section-to-from-pfn-conversion-macros.patch
mm-devm_memremap_pages-use-multi-order-radix-for-zone_device-lookups.patch
mm-introduce-struct-mem_section_usage-to-track-partial-population-of-a-section.patch
mm-introduce-common-definitions-for-the-size-and-mask-of-a-section.patch
mm-cleanup-sparse_init_one_section-return-value.patch
mm-track-active-portions-of-a-section-at-boot.patch
mm-fix-register_new_memory-zone-type-detection.patch
mm-convert-kmalloc_section_memmap-to-populate_section_memmap.patch
mm-prepare-for-hot-add-remove-of-sub-section-ranges.patch
mm-support-section-unaligned-zone_device-memory-ranges.patch
mm-enable-section-unaligned-devm_memremap_pages.patch
libnvdimm-pfn-dax-stop-padding-pmem-namespaces-to-section-alignment.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
