sizeof_namespace_index() fails when NVDIMM devices have the minimum
1024 bytes label storage area. nvdimm_num_label_slots() returns 3
slots while the area is only big enough for 2 slots.
Change nvdimm_num_label_slots() to calculate a number of label slots
according to UEFI 2.7 spec.
Signed-off-by: Toshi Kani <toshi.k...@hpe.com>
Cc: Dan Williams <dan.j.willi...@intel.com>
---
drivers/nvdimm/label.c | 34 ++++++++++++++++++++++++----------
1 file changed, 24 insertions(+), 10 deletions(-)
diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index de66c02f6140..be3ccf7c5413 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -45,9 +45,27 @@ unsigned sizeof_namespace_label(struct nvdimm_drvdata *ndd)
return ndd->nslabel_size;
}
+static size_t __sizeof_namespace_index(u32 nslot)
+{
+ return ALIGN(sizeof(struct nd_namespace_index) + DIV_ROUND_UP(nslot, 8),
+ NSINDEX_ALIGN);
+}
+
+static int __nvdimm_num_label_slots(struct nvdimm_drvdata *ndd,
+ size_t index_size)
+{
+ return (ndd->nsarea.config_size - index_size * 2) /
+ sizeof_namespace_label(ndd);
+}
+
int nvdimm_num_label_slots(struct nvdimm_drvdata *ndd)
{
- return ndd->nsarea.config_size / (sizeof_namespace_label(ndd) + 1);
+ u32 tmp_nslot, n;
+
+ tmp_nslot = ndd->nsarea.config_size / sizeof_namespace_label(ndd);
+ n = __sizeof_namespace_index(tmp_nslot) / NSINDEX_ALIGN;
+
+ return __nvdimm_num_label_slots(ndd, NSINDEX_ALIGN * n);
}
size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd)
@@ -55,18 +73,14 @@ size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd)
u32 nslot, space, size;
/*
- * The minimum index space is 512 bytes, with that amount of
- * index we can describe ~1400 labels which is less than a byte
- * of overhead per label. Round up to a byte of overhead per
- * label and determine the size of the index region. Yes, this
- * starts to waste space at larger config_sizes, but it's
- * unlikely we'll ever see anything but 128K.
+ * Per UEFI 2.7, the minimum size of the Label Storage Area is large
+ * enough to hold 2 index blocks and 2 labels. The minimum index
+ * block size is 256 bytes, and the minimum label size is 256 bytes.
*/
nslot = nvdimm_num_label_slots(ndd);
space = ndd->nsarea.config_size - nslot * sizeof_namespace_label(ndd);
- size = ALIGN(sizeof(struct nd_namespace_index) + DIV_ROUND_UP(nslot, 8),
- NSINDEX_ALIGN) * 2;
- if (size <= space)
+ size = __sizeof_namespace_index(nslot) * 2;
+ if (size <= space && nslot >= 2)
return size / 2;
dev_err(ndd->dev, "label area (%d) too small to host (%d byte)
labels\n",
