util: modify flbas rsvd bits to be used

flbas Bits 6:5 indicate the most significant 2 bits of
the Format Index of the supported LBA Format indicated
in this data structure that was used to format the namespace

Signed-off-by: Steven Seungcheol Lee <[email protected]>

Author: sc108-lee

doc/libnvme.rst

@@ -7745,9 +7745,9 @@ Returns true if given offset is 64bit register, otherwise it returns false.
 
 **Constants**
 
-``NVME_NS_FLBAS_LBA_MASK``
-  Mask to get the index of one of the 16 supported
-  LBA Formats indicated in :c:type:`struct nvme_id_ns <nvme_id_ns>`.lbaf.
+``NVME_NS_FLBAS_LOWER_MASK``
+  Mask to get the index of one of the supported LBA Formats's least significant
+  4bits indicated in :c:type:`struct nvme_id_ns <nvme_id_ns>`.lbaf.
 
 ``NVME_NS_FLBAS_META_EXT``
   Applicable only if format contains metadata. If
@@ -7757,7 +7757,9 @@ Returns true if given offset is 64bit register, otherwise it returns false.
   of the metadata for a command is transferred as a
   separate contiguous buffer of data.
 
-
+``NVME_NS_FLBAS_HIGHER_MASK``
+  Mask to get the index of one of the supported LBA Formats's most significant
+  2bits indicated in :c:type:`struct nvme_id_ns <nvme_id_ns>`.lbaf.
 
 
 .. c:type:: enum nvme_id_ns_mc

doc/man/enum nvme_id_ns_flbas.2

@@ -4,21 +4,29 @@ enum nvme_id_ns_flbas \- This field indicates the LBA data size & metadata size
 .SH SYNOPSIS
 enum nvme_id_ns_flbas {
 .br
-.BI "    NVME_NS_FLBAS_LBA_MASK"
+.BI "    NVME_NS_FLBAS_LOWER_MASK"
 , 
 .br
 .br
 .BI "    NVME_NS_FLBAS_META_EXT"
-
+, 
+.br
+.br
+.BI "    NVME_NS_FLBAS_HIGHER_MASK"
 };
 .SH Constants
-.IP "NVME_NS_FLBAS_LBA_MASK" 12
-Mask to get the index of one of the 16 supported
-LBA Formats indicated in \fIstruct nvme_id_ns\fP.lbaf.
+.IP "NVME_NS_FLBAS_LOWER_MASK" 12
+Mask to get the index of one of the supported LBA Formats's
+least significant 4bits indicated in \fIstruct nvme_id_ns\fP.lbaf.
+
 .IP "NVME_NS_FLBAS_META_EXT" 12
 Applicable only if format contains metadata. If
 this bit is set, indicates that the metadata is
 transferred at the end of the data LBA, creating an
 extended data LBA. If cleared, indicates that all
 of the metadata for a command is transferred as a
 separate contiguous buffer of data.
+
+.IP "NVME_NS_FLBAS_HIGHER_MASK" 12
+Mask to get the index of one of the supported LBA Formats's
+most significant 2bits indicated in \fIstruct nvme_id_ns\fP.lbaf.

src/nvme/linux.c

@@ -337,14 +337,14 @@ int nvme_get_ana_log_len(int fd, size_t *analen)
 int nvme_get_logical_block_size(int fd, __u32 nsid, int *blksize)
 {
 	struct nvme_id_ns ns;
-	int flbas;
+	__u8 flbas;
 	int ret;
 
 	ret = nvme_identify_ns(fd, nsid, &ns);
 	if (ret)
 		return ret;
 
-	flbas = ns.flbas & NVME_NS_FLBAS_LBA_MASK;
+	nvme_id_ns_flbas_to_lbaf_inuse(ns.flbas, &flbas);
 	*blksize = 1 << ns.lbaf[flbas].ds;
 
 	return 0;

src/nvme/tree.c

@@ -1670,14 +1670,14 @@ static int nvme_ns_init(struct nvme_ns *n)
 	struct nvme_id_ns ns = { };
 	uint8_t buffer[NVME_IDENTIFY_DATA_SIZE] = { };
 	struct nvme_ns_id_desc *descs = (void *)buffer;
-	int flbas;
+	uint8_t flbas;
 	int ret;
 
 	ret = nvme_ns_identify(n, &ns);
 	if (ret)
 		return ret;
 
-	flbas = ns.flbas & NVME_NS_FLBAS_LBA_MASK;
+	nvme_id_ns_flbas_to_lbaf_inuse(ns.flbas, &flbas);
 	n->lba_shift = ns.lbaf[flbas].ds;
 	n->lba_size = 1 << n->lba_shift;
 	n->lba_count = le64_to_cpu(ns.nsze);

src/nvme/types.h

@@ -1700,18 +1700,25 @@ enum nvme_id_nsfeat {
  * enum nvme_id_ns_flbas - This field indicates the LBA data size & metadata
  * 			   size combination that the namespace has been
  * 			   formatted with
- * @NVME_NS_FLBAS_LBA_MASK: Mask to get the index of one of the 16 supported
- * 			    LBA Formats indicated in &struct nvme_id_ns.lbaf.
- * @NVME_NS_FLBAS_META_EXT: Applicable only if format contains metadata. If
- * 			    this bit is set, indicates that the metadata is
- * 			    transferred at the end of the data LBA, creating an
- * 			    extended data LBA. If cleared, indicates that all
- * 			    of the metadata for a command is transferred as a
- * 			    separate contiguous buffer of data.
+ * @NVME_NS_FLBAS_LOWER_MASK:	Mask to get the index of one of the supported
+ *				LBA Formats's least significant
+ *				4bits indicated in
+ *				:c:type:`struct nvme_id_ns <nvme_id_ns>`.lbaf.
+ * @NVME_NS_FLBAS_META_EXT:	Applicable only if format contains metadata. If
+ *				this bit is set, indicates that the metadata is
+ *				transferred at the end of the data LBA, creating an
+ *				extended data LBA. If cleared, indicates that all
+ *				of the metadata for a command is transferred as a
+ *				separate contiguous buffer of data.
+ * @NVME_NS_FLBAS_HIGHER_MASK:  Mask to get the index of one of
+ *				the supported LBA Formats's most significant
+ *				2bits indicated in
+ *				:c:type:`struct nvme_id_ns <nvme_id_ns>`.lbaf.
  */
 enum nvme_id_ns_flbas {
-	NVME_NS_FLBAS_LBA_MASK		= 15 << 0,
+	NVME_NS_FLBAS_LOWER_MASK	= 15 << 0,
 	NVME_NS_FLBAS_META_EXT		= 1 << 4,
+	NVME_NS_FLBAS_HIGHER_MASK	= 3 << 5,
 };
 
 /**

src/nvme/util.h

@@ -363,4 +363,10 @@ static inline void nvme_feature_decode_namespace_write_protect(__u32 value,
 {
 	*wps	= NVME_FEAT_WP_WPS(value);
 }
+
+static inline void nvme_id_ns_flbas_to_lbaf_inuse(__u8 flbas, __u8 *lbaf_inuse)
+{
+	*lbaf_inuse = (((flbas & NVME_NS_FLBAS_HIGHER_MASK) >> 1) \
+		| (flbas & NVME_NS_FLBAS_LOWER_MASK));
+}
 #endif /* _LIBNVME_UTIL_H */

test/test.c

@@ -267,13 +267,15 @@ static int test_namespace(nvme_ns_t n)
 	struct nvme_id_ns ns = { 0 }, allocated = { 0 };
 	struct nvme_ns_id_desc descs = { 0 };
 	__u32 result = 0;
+	__u8 flbas;
 
 	ret = nvme_ns_identify(n, &ns);
 	if (ret)
 		return ret;
 
+	nvme_id_ns_flbas_to_lbaf_inuse(ns.flbas, &flbas);
 	printf("%s: nsze:%lx lba size:%d\n", nvme_ns_get_name(n), le64_to_cpu(ns.nsze),
-		1 << ns.lbaf[ns.flbas & NVME_NS_FLBAS_LBA_MASK].ds);
+		1 << ns.lbaf[flbas].ds);
 
 	ret = nvme_identify_allocated_ns(fd, nsid, &allocated);
 	if (!ret)