diff mbox series

[ndctl,v5,3/6] libcxl: return the partition alignment field in bytes

Message ID 6b937b09b61ddf95e069fd7acfda0c5bbb845be8.1644455619.git.alison.schofield@intel.com (mailing list archive)
State Superseded
Headers show
Series Add partitioning support for CXL memdevs | expand

Commit Message

Alison Schofield Feb. 10, 2022, 2:05 a.m. UTC 
From: Alison Schofield <alison.schofield@intel.com>

Per the CXL specification, the partition alignment field reports
the alignment value in multiples of 256MB. In the libcxl API, values
for all capacity fields are defined to return bytes.

Update the partition alignment accessor to return bytes so that it
is in sync with other capacity related fields. Use the helpers
cmd_to_identify() and cxl_capacity_to_bytes() to accomplish.

Since this is early in the development cycle, the expectation is that
no third party consumers of this library have come to depend on the
encoded capacity field. If that is not the case, the original format
can be restored, and a new _bytes version introduced.

Signed-off-by: Alison Schofield <alison.schofield@intel.com>
---

 cxl/lib/libcxl.c | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

Comments

Dan Williams Feb. 10, 2022, 2:31 a.m. UTC | #1 
On Wed, Feb 9, 2022 at 6:01 PM <alison.schofield@intel.com> wrote:
>
> From: Alison Schofield <alison.schofield@intel.com>
>
> Per the CXL specification, the partition alignment field reports
> the alignment value in multiples of 256MB. In the libcxl API, values
> for all capacity fields are defined to return bytes.
>
> Update the partition alignment accessor to return bytes so that it
> is in sync with other capacity related fields. Use the helpers
> cmd_to_identify() and cxl_capacity_to_bytes() to accomplish.
>
> Since this is early in the development cycle, the expectation is that
> no third party consumers of this library have come to depend on the
> encoded capacity field. If that is not the case, the original format
> can be restored, and a new _bytes version introduced.
>
> Signed-off-by: Alison Schofield <alison.schofield@intel.com>

Looks good,

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
diff mbox series

Patch

diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c
index 9413384..c05c13c 100644
--- a/cxl/lib/libcxl.c
+++ b/cxl/lib/libcxl.c
@@ -2308,15 +2308,12 @@  CXL_EXPORT int cxl_cmd_identify_get_fw_rev(struct cxl_cmd *cmd, char *fw_rev,
 CXL_EXPORT unsigned long long cxl_cmd_identify_get_partition_align(
 		struct cxl_cmd *cmd)
 {
-	struct cxl_cmd_identify *id =
-			(struct cxl_cmd_identify *)cmd->send_cmd->out.payload;
+	struct cxl_cmd_identify *c;
 
-	if (cmd->send_cmd->id != CXL_MEM_COMMAND_ID_IDENTIFY)
-		return -EINVAL;
-	if (cmd->status < 0)
-		return cmd->status;
-
-	return le64_to_cpu(id->partition_align);
+	c = cmd_to_identify(cmd);
+	if (!c)
+		return ULLONG_MAX;
+	return cxl_capacity_to_bytes(c->partition_align);
 }
 
 CXL_EXPORT unsigned int cxl_cmd_identify_get_label_size(struct cxl_cmd *cmd)