From 6255d23452809ddc6d48083c35fc935e4fa420d8 Mon Sep 17 00:00:00 2001

From: Vishal Verma <vishal.l.verma@intel.com>

Date: Thu, 7 Oct 2021 02:21:34 -0600

Subject: [PATCH 041/217] libcxl: add interfaces for label operations

Add libcxl interfaces to allow performinfg label (LSA) manipulations.

Add a 'cxl_cmd_new_set_lsa' interface to create a 'Set LSA' mailbox

command payload, and interfaces to read, write, and zero the LSA area on

a memdev.

Cc: Dan Williams <dan.j.williams@intel.com>

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

Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>

---

 cxl/lib/libcxl.c   | 158 +++++++++++++++++++++++++++++++++++++++++++++

 cxl/lib/libcxl.sym |   4 ++

 cxl/lib/private.h  |   6 ++

 cxl/libcxl.h       |   8 +++

 4 files changed, 176 insertions(+)

diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c

index 60ed646..f0664be 100644

--- a/cxl/lib/libcxl.c

+++ b/cxl/lib/libcxl.c

@@ -1197,3 +1197,161 @@ CXL_EXPORT int cxl_cmd_get_out_size(struct cxl_cmd *cmd)

 {

 	return cmd->send_cmd->out.size;

 }

+

+CXL_EXPORT struct cxl_cmd *cxl_cmd_new_write_label(struct cxl_memdev *memdev,

+		void *lsa_buf, unsigned int offset, unsigned int length)

+{

+	struct cxl_ctx *ctx = cxl_memdev_get_ctx(memdev);

+	struct cxl_cmd_set_lsa *set_lsa;

+	struct cxl_cmd *cmd;

+	int rc;

+

+	cmd = cxl_cmd_new_generic(memdev, CXL_MEM_COMMAND_ID_SET_LSA);

+	if (!cmd)

+		return NULL;

+

+	/* this will allocate 'in.payload' */

+	rc = cxl_cmd_set_input_payload(cmd, NULL, sizeof(*set_lsa) + length);

+	if (rc) {

+		err(ctx, "%s: cmd setup failed: %s\n",

+			cxl_memdev_get_devname(memdev), strerror(-rc));

+		goto out_fail;

+	}

+	set_lsa = (struct cxl_cmd_set_lsa *)cmd->send_cmd->in.payload;

+	set_lsa->offset = cpu_to_le32(offset);

+	memcpy(set_lsa->lsa_data, lsa_buf, length);

+

+	return cmd;

+

+out_fail:

+	cxl_cmd_unref(cmd);

+	return NULL;

+}

+

+enum lsa_op {

+	LSA_OP_GET,

+	LSA_OP_SET,

+	LSA_OP_ZERO,

+};

+

+static int __lsa_op(struct cxl_memdev *memdev, int op, void *buf,

+		size_t length, size_t offset)

+{

+	const char *devname = cxl_memdev_get_devname(memdev);

+	struct cxl_ctx *ctx = cxl_memdev_get_ctx(memdev);

+	void *zero_buf = NULL;

+	struct cxl_cmd *cmd;

+	ssize_t ret_len;

+	int rc = 0;

+

+	switch (op) {

+	case LSA_OP_GET:

+		cmd = cxl_cmd_new_read_label(memdev, offset, length);

+		if (!cmd)

+			return -ENOMEM;

+		rc = cxl_cmd_set_output_payload(cmd, buf, length);

+		if (rc) {

+			err(ctx, "%s: cmd setup failed: %s\n",

+			    cxl_memdev_get_devname(memdev), strerror(-rc));

+			goto out;

+		}

+		break;

+	case LSA_OP_ZERO:

+		zero_buf = calloc(1, length);

+		if (!zero_buf)

+			return -ENOMEM;

+		buf = zero_buf;

+		/* fall through */

+	case LSA_OP_SET:

+		cmd = cxl_cmd_new_write_label(memdev, buf, offset, length);

+		if (!cmd) {

+			rc = -ENOMEM;

+			goto out_free;

+		}

+		break;

+	default:

+		return -EOPNOTSUPP;

+	}

+

+	rc = cxl_cmd_submit(cmd);

+	if (rc < 0) {

+		err(ctx, "%s: cmd submission failed: %s\n",

+			devname, strerror(-rc));

+		goto out;

+	}

+

+	rc = cxl_cmd_get_mbox_status(cmd);

+	if (rc != 0) {

+		err(ctx, "%s: firmware status: %d\n",

+			devname, rc);

+		rc = -ENXIO;

+		goto out;

+	}

+

+	if (op == LSA_OP_GET) {

+		ret_len = cxl_cmd_read_label_get_payload(cmd, buf, length);

+		if (ret_len < 0) {

+			rc = ret_len;

+			goto out;

+		}

+	}

+

+out:

+	cxl_cmd_unref(cmd);

+out_free:

+	free(zero_buf);

+	return rc;

+

+}

+

+static int lsa_op(struct cxl_memdev *memdev, int op, void *buf,

+		size_t length, size_t offset)

+{

+	const char *devname = cxl_memdev_get_devname(memdev);

+	struct cxl_ctx *ctx = cxl_memdev_get_ctx(memdev);

+	size_t remaining = length, cur_len, cur_off = 0;

+	int label_iter_max, rc = 0;

+

+	if (op != LSA_OP_ZERO && buf == NULL) {

+		err(ctx, "%s: LSA buffer cannot be NULL\n", devname);

+		return -EINVAL;

+	}

+

+	if (length == 0)

+		return 0;

+

+	label_iter_max = memdev->payload_max - sizeof(struct cxl_cmd_set_lsa);

+	while (remaining) {

+		cur_len = min((size_t)label_iter_max, remaining);

+		rc = __lsa_op(memdev, op, buf + cur_off,

+				cur_len, offset + cur_off);

+		if (rc)

+			break;

+

+		remaining -= cur_len;

+		cur_off += cur_len;

+	}

+

+	if (rc && (op == LSA_OP_SET))

+		err(ctx, "%s: labels may be in an inconsistent state\n",

+			devname);

+	return rc;

+}

+

+CXL_EXPORT int cxl_memdev_zero_label(struct cxl_memdev *memdev, size_t length,

+		size_t offset)

+{

+	return lsa_op(memdev, LSA_OP_ZERO, NULL, length, offset);

+}

+

+CXL_EXPORT int cxl_memdev_write_label(struct cxl_memdev *memdev, void *buf,

+		size_t length, size_t offset)

+{

+	return lsa_op(memdev, LSA_OP_SET, buf, length, offset);

+}

+

+CXL_EXPORT int cxl_memdev_read_label(struct cxl_memdev *memdev, void *buf,

+		size_t length, size_t offset)

+{

+	return lsa_op(memdev, LSA_OP_GET, buf, length, offset);

+}

diff --git a/cxl/lib/libcxl.sym b/cxl/lib/libcxl.sym

index f3b0c63..077d104 100644

--- a/cxl/lib/libcxl.sym

+++ b/cxl/lib/libcxl.sym

@@ -66,6 +66,10 @@ global:

 	cxl_cmd_read_label_get_payload;

 	cxl_memdev_get_label_size;

 	cxl_memdev_nvdimm_bridge_active;

+	cxl_cmd_new_write_label;

+	cxl_memdev_zero_label;

+	cxl_memdev_write_label;

+	cxl_memdev_read_label;

 local:

         *;

 };

diff --git a/cxl/lib/private.h b/cxl/lib/private.h

index 525c41e..a1b8b50 100644

--- a/cxl/lib/private.h

+++ b/cxl/lib/private.h

@@ -87,6 +87,12 @@ struct cxl_cmd_get_lsa_in {

 	le32 length;

 } __attribute__((packed));

+struct cxl_cmd_set_lsa {

+	le32 offset;

+	le32 rsvd;

+	unsigned char lsa_data[0];

+} __attribute__ ((packed));

+

 struct cxl_cmd_get_health_info {

 	u8 health_status;

 	u8 media_status;

diff --git a/cxl/libcxl.h b/cxl/libcxl.h

index 535e349..89d35ba 100644

--- a/cxl/libcxl.h

+++ b/cxl/libcxl.h

@@ -44,6 +44,12 @@ unsigned long long cxl_memdev_get_ram_size(struct cxl_memdev *memdev);

 const char *cxl_memdev_get_firmware_verison(struct cxl_memdev *memdev);

 size_t cxl_memdev_get_label_size(struct cxl_memdev *memdev);

 int cxl_memdev_nvdimm_bridge_active(struct cxl_memdev *memdev);

+int cxl_memdev_zero_label(struct cxl_memdev *memdev, size_t length,

+		size_t offset);

+int cxl_memdev_read_label(struct cxl_memdev *memdev, void *buf, size_t length,

+		size_t offset);

+int cxl_memdev_write_label(struct cxl_memdev *memdev, void *buf, size_t length,

+		size_t offset);

 #define cxl_memdev_foreach(ctx, memdev) \

         for (memdev = cxl_memdev_get_first(ctx); \

@@ -101,6 +107,8 @@ struct cxl_cmd *cxl_cmd_new_read_label(struct cxl_memdev *memdev,

 		unsigned int offset, unsigned int length);

 ssize_t cxl_cmd_read_label_get_payload(struct cxl_cmd *cmd, void *buf,

 		unsigned int length);

+struct cxl_cmd *cxl_cmd_new_write_label(struct cxl_memdev *memdev,

+		void *buf, unsigned int offset, unsigned int length);

 #ifdef __cplusplus

 } /* extern "C" */

-- 

2.27.0