From c415cebe4b5ca50e06db78a4719f312e33106936 Mon Sep 17 00:00:00 2001

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

Date: Thu, 7 Oct 2021 02:21:35 -0600

Subject: [PATCH 042/217] cxl: add commands to read, write, and zero labels

Add the following cxl-cli commands: read-labels, write-labels,

zero-labels. They operate on a CXL memdev, or a set of memdevs, and

allow interacting with the label storage area (LSA) on the device.

Add man pages for the above cxl-cli commands.

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>

---

 Documentation/cxl/Makefile.am            |   5 +-

 Documentation/cxl/cxl-read-labels.txt    |  33 +++

 Documentation/cxl/cxl-write-labels.txt   |  32 +++

 Documentation/cxl/cxl-zero-labels.txt    |  29 ++

 Documentation/cxl/labels-description.txt |   8 +

 Documentation/cxl/labels-options.txt     |  17 ++

 Documentation/cxl/memdev-option.txt      |   4 +

 cxl/Makefile.am                          |   1 +

 cxl/builtin.h                            |   5 +

 cxl/cxl.c                                |   3 +

 cxl/memdev.c                             | 324 +++++++++++++++++++++++

 11 files changed, 460 insertions(+), 1 deletion(-)

 create mode 100644 Documentation/cxl/cxl-read-labels.txt

 create mode 100644 Documentation/cxl/cxl-write-labels.txt

 create mode 100644 Documentation/cxl/cxl-zero-labels.txt

 create mode 100644 Documentation/cxl/labels-description.txt

 create mode 100644 Documentation/cxl/labels-options.txt

 create mode 100644 Documentation/cxl/memdev-option.txt

 create mode 100644 cxl/memdev.c

diff --git a/Documentation/cxl/Makefile.am b/Documentation/cxl/Makefile.am

index db98dd7..efabaa3 100644

--- a/Documentation/cxl/Makefile.am

+++ b/Documentation/cxl/Makefile.am

@@ -19,7 +19,10 @@ endif

 man1_MANS = \

 	cxl.1 \

-	cxl-list.1

+	cxl-list.1 \

+	cxl-read-labels.1 \

+	cxl-write-labels.1 \

+	cxl-zero-labels.1

 EXTRA_DIST = $(man1_MANS)

diff --git a/Documentation/cxl/cxl-read-labels.txt b/Documentation/cxl/cxl-read-labels.txt

new file mode 100644

index 0000000..143f296

--- /dev/null

+++ b/Documentation/cxl/cxl-read-labels.txt

@@ -0,0 +1,33 @@

+// SPDX-License-Identifier: GPL-2.0

+

+cxl-read-labels(1)

+==================

+

+NAME

+----

+cxl-read-labels - read out the label area on a CXL memdev

+

+SYNOPSIS

+--------

+[verse]

+'cxl read-labels' <mem0> [<mem1>..<memN>] [<options>]

+

+include::labels-description.txt[]

+This command dumps the raw binary data in a memdev's label area to stdout or a

+file.  In the multi-memdev case the data is concatenated.

+

+OPTIONS

+-------

+include::labels-options.txt[]

+

+-o::

+--output::

+	output file

+

+include::../copyright.txt[]

+

+SEE ALSO

+--------

+linkcxl:cxl-write-labels[1],

+linkcxl:cxl-zero-labels[1],

+CXL-2.0 9.13.2

diff --git a/Documentation/cxl/cxl-write-labels.txt b/Documentation/cxl/cxl-write-labels.txt

new file mode 100644

index 0000000..75f42a5

--- /dev/null

+++ b/Documentation/cxl/cxl-write-labels.txt

@@ -0,0 +1,32 @@

+// SPDX-License-Identifier: GPL-2.0

+

+cxl-write-labels(1)

+===================

+

+NAME

+----

+cxl-write-labels - write data to the label area on a memdev

+

+SYNOPSIS

+--------

+[verse]

+'cxl write-labels <mem> [-i <filename>]'

+

+include::labels-description.txt[]

+Read data from the input filename, or stdin, and write it to the given

+<mem> device. Note that the device must not be active in any region, or

+actively registered with the nvdimm subsystem. If it is, the kernel will

+not allow write access to the device's label data area.

+

+OPTIONS

+-------

+include::labels-options.txt[]

+-i::

+--input::

+	input file

+

+SEE ALSO

+--------

+linkcxl:cxl-read-labels[1],

+linkcxl:cxl-zero-labels[1],

+CXL-2.0 9.13.2

diff --git a/Documentation/cxl/cxl-zero-labels.txt b/Documentation/cxl/cxl-zero-labels.txt

new file mode 100644

index 0000000..bf95b24

--- /dev/null

+++ b/Documentation/cxl/cxl-zero-labels.txt

@@ -0,0 +1,29 @@

+// SPDX-License-Identifier: GPL-2.0

+

+cxl-zero-labels(1)

+==================

+

+NAME

+----

+cxl-zero-labels - zero out the label area on a set of memdevs

+

+SYNOPSIS

+--------

+[verse]

+'cxl zero-labels' <mem0> [<mem1>..<memN>] [<options>]

+

+include::labels-description.txt[]

+This command resets the device to its default state by

+deleting all labels.

+

+OPTIONS

+-------

+include::labels-options.txt[]

+

+include::../copyright.txt[]

+

+SEE ALSO

+--------

+linkcxl:cxl-read-labels[1],

+linkcxl:cxl-write-labels[1],

+CXL-2.0 9.13.2

diff --git a/Documentation/cxl/labels-description.txt b/Documentation/cxl/labels-description.txt

new file mode 100644

index 0000000..f60bd5d

--- /dev/null

+++ b/Documentation/cxl/labels-description.txt

@@ -0,0 +1,8 @@

+// SPDX-License-Identifier: GPL-2.0

+

+DESCRIPTION

+-----------

+The region label area is a small persistent partition of capacity

+available on some CXL memory devices. The label area is used to

+and configure or determine the set of memory devices participating

+in different interleave sets.

diff --git a/Documentation/cxl/labels-options.txt b/Documentation/cxl/labels-options.txt

new file mode 100644

index 0000000..06fbac3

--- /dev/null

+++ b/Documentation/cxl/labels-options.txt

@@ -0,0 +1,17 @@

+// SPDX-License-Identifier: GPL-2.0

+

+<memory device(s)>::

+include::memdev-option.txt[]

+

+-s::

+--size=::

+	Limit the operation to the given number of bytes. A size of 0

+	indicates to operate over the entire label capacity.

+

+-O::

+--offset=::

+	Begin the operation at the given offset into the label area.

+

+-v::

+	Turn on verbose debug messages in the library (if libcxl was built with

+	logging and debug enabled).

diff --git a/Documentation/cxl/memdev-option.txt b/Documentation/cxl/memdev-option.txt

new file mode 100644

index 0000000..e778582

--- /dev/null

+++ b/Documentation/cxl/memdev-option.txt

@@ -0,0 +1,4 @@

+// SPDX-License-Identifier: GPL-2.0

+A 'memX' device name, or a memdev id number. Restrict the operation to

+the specified memdev(s). The keyword 'all' can be specified to indicate

+the lack of any restriction.

diff --git a/cxl/Makefile.am b/cxl/Makefile.am

index 98606b9..da9f91d 100644

--- a/cxl/Makefile.am

+++ b/cxl/Makefile.am

@@ -10,6 +10,7 @@ config.h: $(srcdir)/Makefile.am

 cxl_SOURCES =\

 		cxl.c \

 		list.c \

+		memdev.c \

 		../util/json.c \

 		builtin.h

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

index 3797f98..78eca6e 100644

--- a/cxl/builtin.h

+++ b/cxl/builtin.h

@@ -5,4 +5,9 @@

 struct cxl_ctx;

 int cmd_list(int argc, const char **argv, struct cxl_ctx *ctx);

+int cmd_write_labels(int argc, const char **argv, struct cxl_ctx *ctx);

+int cmd_read_labels(int argc, const char **argv, struct cxl_ctx *ctx);

+int cmd_zero_labels(int argc, const char **argv, struct cxl_ctx *ctx);

+int cmd_init_labels(int argc, const char **argv, struct cxl_ctx *ctx);

+int cmd_check_labels(int argc, const char **argv, struct cxl_ctx *ctx);

 #endif /* _CXL_BUILTIN_H_ */

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

index a7725f8..4b1661d 100644

--- a/cxl/cxl.c

+++ b/cxl/cxl.c

@@ -61,6 +61,9 @@ static struct cmd_struct commands[] = {

 	{ "version", .c_fn = cmd_version },

 	{ "list", .c_fn = cmd_list },

 	{ "help", .c_fn = cmd_help },

+	{ "zero-labels", .c_fn = cmd_zero_labels },

+	{ "read-labels", .c_fn = cmd_read_labels },

+	{ "write-labels", .c_fn = cmd_write_labels },

 };

 int main(int argc, const char **argv)

diff --git a/cxl/memdev.c b/cxl/memdev.c

new file mode 100644

index 0000000..5ee38e5

--- /dev/null

+++ b/cxl/memdev.c

@@ -0,0 +1,324 @@

+// SPDX-License-Identifier: GPL-2.0

+/* Copyright (C) 2020-2021 Intel Corporation. All rights reserved. */

+#include <stdio.h>

+#include <errno.h>

+#include <stdlib.h>

+#include <unistd.h>

+#include <limits.h>

+#include <util/log.h>

+#include <util/filter.h>

+#include <cxl/libcxl.h>

+#include <util/parse-options.h>

+#include <ccan/minmax/minmax.h>

+#include <ccan/array_size/array_size.h>

+

+struct action_context {

+	FILE *f_out;

+	FILE *f_in;

+};

+

+static struct parameters {

+	const char *outfile;

+	const char *infile;

+	unsigned len;

+	unsigned offset;

+	bool verbose;

+} param;

+

+#define fail(fmt, ...) \

+do { \

+	fprintf(stderr, "cxl-%s:%s:%d: " fmt, \

+			VERSION, __func__, __LINE__, ##__VA_ARGS__); \

+} while (0)

+

+#define BASE_OPTIONS() \

+OPT_BOOLEAN('v',"verbose", &param.verbose, "turn on debug")

+

+#define READ_OPTIONS() \

+OPT_STRING('o', "output", &param.outfile, "output-file", \

+	"filename to write label area contents")

+

+#define WRITE_OPTIONS() \

+OPT_STRING('i', "input", &param.infile, "input-file", \

+	"filename to read label area data")

+

+#define LABEL_OPTIONS() \

+OPT_UINTEGER('s', "size", &param.len, "number of label bytes to operate"), \

+OPT_UINTEGER('O', "offset", &param.offset, \

+	"offset into the label area to start operation")

+

+static const struct option read_options[] = {

+	BASE_OPTIONS(),

+	LABEL_OPTIONS(),

+	READ_OPTIONS(),

+	OPT_END(),

+};

+

+static const struct option write_options[] = {

+	BASE_OPTIONS(),

+	LABEL_OPTIONS(),

+	WRITE_OPTIONS(),

+	OPT_END(),

+};

+

+static const struct option zero_options[] = {

+	BASE_OPTIONS(),

+	LABEL_OPTIONS(),

+	OPT_END(),

+};

+

+static int action_zero(struct cxl_memdev *memdev, struct action_context *actx)

+{

+	size_t size;

+	int rc;

+

+	if (param.len)

+		size = param.len;

+	else

+		size = cxl_memdev_get_label_size(memdev);

+

+	if (cxl_memdev_nvdimm_bridge_active(memdev)) {

+		fprintf(stderr,

+			"%s: has active nvdimm bridge, abort label write\n",

+			cxl_memdev_get_devname(memdev));

+		return -EBUSY;

+	}

+

+	rc = cxl_memdev_zero_label(memdev, size, param.offset);

+	if (rc < 0)

+		fprintf(stderr, "%s: label zeroing failed: %s\n",

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

+

+	return rc;

+}

+

+static int action_write(struct cxl_memdev *memdev, struct action_context *actx)

+{

+	size_t size = param.len, read_len;

+	unsigned char *buf;

+	int rc;

+

+	if (cxl_memdev_nvdimm_bridge_active(memdev)) {

+		fprintf(stderr,

+			"%s: has active nvdimm bridge, abort label write\n",

+			cxl_memdev_get_devname(memdev));

+		return -EBUSY;

+	}

+

+	if (!size) {

+		size_t label_size = cxl_memdev_get_label_size(memdev);

+

+		fseek(actx->f_in, 0L, SEEK_END);

+		size = ftell(actx->f_in);

+		fseek(actx->f_in, 0L, SEEK_SET);

+

+		if (size > label_size) {

+			fprintf(stderr,

+				"File size (%zu) greater than label area size (%zu), aborting\n",

+				size, label_size);

+			return -EINVAL;

+		}

+	}

+

+	buf = calloc(1, size);

+	if (!buf)

+		return -ENOMEM;

+

+	read_len = fread(buf, 1, size, actx->f_in);

+	if (read_len != size) {

+		rc = -ENXIO;

+		goto out;

+	}

+

+	rc = cxl_memdev_write_label(memdev, buf, size, param.offset);

+	if (rc < 0)

+		fprintf(stderr, "%s: label write failed: %s\n",

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

+

+out:

+	free(buf);

+	return rc;

+}

+

+static int action_read(struct cxl_memdev *memdev, struct action_context *actx)

+{

+	size_t size, write_len;

+	char *buf;

+	int rc;

+

+	if (param.len)

+		size = param.len;

+	else

+		size = cxl_memdev_get_label_size(memdev);

+

+	buf = calloc(1, size);

+	if (!buf)

+		return -ENOMEM;

+

+	rc = cxl_memdev_read_label(memdev, buf, size, param.offset);

+	if (rc < 0) {

+		fprintf(stderr, "%s: label read failed: %s\n",

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

+		goto out;

+	}

+

+	write_len = fwrite(buf, 1, size, actx->f_out);

+	if (write_len != size) {

+		rc = -ENXIO;

+		goto out;

+	}

+	fflush(actx->f_out);

+

+out:

+	free(buf);

+	return rc;

+}

+

+static int memdev_action(int argc, const char **argv, struct cxl_ctx *ctx,

+		int (*action)(struct cxl_memdev *memdev, struct action_context *actx),

+		const struct option *options, const char *usage)

+{

+	struct cxl_memdev *memdev, *single = NULL;

+	struct action_context actx = { 0 };

+	int i, rc = 0, count = 0, err = 0;

+	const char * const u[] = {

+		usage,

+		NULL

+	};

+	unsigned long id;

+

+	argc = parse_options(argc, argv, options, u, 0);

+

+	if (argc == 0)

+		usage_with_options(u, options);

+	for (i = 0; i < argc; i++) {

+		if (strcmp(argv[i], "all") == 0) {

+			argv[0] = "all";

+			argc = 1;

+			break;

+		}

+

+		if (sscanf(argv[i], "mem%lu", &id) != 1) {

+			fprintf(stderr, "'%s' is not a valid memdev name\n",

+					argv[i]);

+			err++;

+		}

+	}

+

+	if (err == argc) {

+		usage_with_options(u, options);

+		return -EINVAL;

+	}

+

+	if (!param.outfile)

+		actx.f_out = stdout;

+	else {

+		actx.f_out = fopen(param.outfile, "w+");

+		if (!actx.f_out) {

+			fprintf(stderr, "failed to open: %s: (%s)\n",

+					param.outfile, strerror(errno));

+			rc = -errno;

+			goto out;

+		}

+	}

+

+	if (!param.infile) {

+		actx.f_in = stdin;

+	} else {

+		actx.f_in = fopen(param.infile, "r");

+		if (!actx.f_in) {

+			fprintf(stderr, "failed to open: %s: (%s)\n",

+					param.infile, strerror(errno));

+			rc = -errno;

+			goto out_close_fout;

+		}

+	}

+

+	if (param.verbose)

+		cxl_set_log_priority(ctx, LOG_DEBUG);

+

+	rc = 0;

+	err = 0;

+	count = 0;

+

+	for (i = 0; i < argc; i++) {

+		if (sscanf(argv[i], "mem%lu", &id) != 1

+				&& strcmp(argv[i], "all") != 0)

+			continue;

+

+		cxl_memdev_foreach (ctx, memdev) {

+			if (!util_cxl_memdev_filter(memdev, argv[i]))

+				continue;

+

+			if (action == action_write) {

+				single = memdev;

+				rc = 0;

+			} else

+				rc = action(memdev, &actx);

+

+			if (rc == 0)

+				count++;

+			else if (rc && !err)

+				err = rc;

+		}

+	}

+	rc = err;

+

+	if (action == action_write) {

+		if (count > 1) {

+			error("write-labels only supports writing a single memdev\n");

+			usage_with_options(u, options);

+			return -EINVAL;

+		} else if (single) {

+			rc = action(single, &actx);

+			if (rc)

+				count = 0;

+		}

+	}

+

+	if (actx.f_in != stdin)

+		fclose(actx.f_in);

+

+ out_close_fout:

+	if (actx.f_out != stdout)

+		fclose(actx.f_out);

+

+ out:

+	/*

+	 * count if some actions succeeded, 0 if none were attempted,

+	 * negative error code otherwise.

+	 */

+	if (count > 0)

+		return count;

+	return rc;

+}

+

+int cmd_write_labels(int argc, const char **argv, struct cxl_ctx *ctx)

+{

+	int count = memdev_action(argc, argv, ctx, action_write, write_options,

+			"cxl write-labels <memdev> [-i <filename>]");

+

+	fprintf(stderr, "wrote %d mem%s\n", count >= 0 ? count : 0,

+			count > 1 ? "s" : "");

+	return count >= 0 ? 0 : EXIT_FAILURE;

+}

+

+int cmd_read_labels(int argc, const char **argv, struct cxl_ctx *ctx)

+{

+	int count = memdev_action(argc, argv, ctx, action_read, read_options,

+			"cxl read-labels <mem0> [<mem1>..<memN>] [-o <filename>]");

+

+	fprintf(stderr, "read %d mem%s\n", count >= 0 ? count : 0,

+			count > 1 ? "s" : "");

+	return count >= 0 ? 0 : EXIT_FAILURE;

+}

+

+int cmd_zero_labels(int argc, const char **argv, struct cxl_ctx *ctx)

+{

+	int count = memdev_action(argc, argv, ctx, action_zero, zero_options,

+			"cxl zero-labels <mem0> [<mem1>..<memN>] [<options>]");

+

+	fprintf(stderr, "zeroed %d mem%s\n", count >= 0 ? count : 0,

+			count > 1 ? "s" : "");

+	return count >= 0 ? 0 : EXIT_FAILURE;

+}

-- 

2.27.0