From 6624f4fdf7ba43039111c996dfd3982b4fdc43bc Mon Sep 17 00:00:00 2001

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

Date: Thu, 14 Jul 2022 10:02:44 -0700

Subject: [PATCH 184/217] cxl/memdev: Add {reserve,free}-dpa commands

Add helper commands for managing allocations of DPA (device physical

address) capacity on a set of CXL memory devices.

The main convenience this command affords is automatically picking the next

decoder to allocate per-memdev.

For example, to allocate 256MiB from all endpoints that are covered by a

given root decoder, and collect those resulting endpoint-decoders into an

array:

  readarray -t mem < <(cxl list -M -d $decoder | jq -r ".[].memdev")

  readarray -t endpoint < <(cxl reserve-dpa -t pmem ${mem[*]} -s $((256<<20)) |

                            jq -r ".[] | .decoder.decoder")

Link: https://lore.kernel.org/r/165781816425.1555691.17958897857798325111.stgit@dwillia2-xfh.jf.intel.com

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

[vishal: fix typo pointed out by Jonathan]

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

---

 .clang-format                         |   1 +

 Documentation/cxl/cxl-free-dpa.txt    |  53 +++++

 Documentation/cxl/cxl-reserve-dpa.txt |  67 ++++++

 Documentation/cxl/lib/libcxl.txt      |   2 +

 Documentation/cxl/meson.build         |   2 +

 cxl/builtin.h                         |   2 +

 cxl/cxl.c                             |   2 +

 cxl/filter.c                          |   4 +-

 cxl/filter.h                          |   2 +

 cxl/lib/libcxl.c                      |  86 ++++++++

 cxl/lib/libcxl.sym                    |   4 +

 cxl/libcxl.h                          |   9 +

 cxl/memdev.c                          | 280 +++++++++++++++++++++++++-

 13 files changed, 511 insertions(+), 3 deletions(-)

 create mode 100644 Documentation/cxl/cxl-free-dpa.txt

 create mode 100644 Documentation/cxl/cxl-reserve-dpa.txt

diff --git a/.clang-format b/.clang-format

index 6aabcb6..7254a1b 100644

--- a/.clang-format

+++ b/.clang-format

@@ -81,6 +81,7 @@ ForEachMacros:

   - 'cxl_bus_foreach'

   - 'cxl_port_foreach'

   - 'cxl_decoder_foreach'

+  - 'cxl_decoder_foreach_reverse'

   - 'cxl_target_foreach'

   - 'cxl_dport_foreach'

   - 'cxl_endpoint_foreach'

diff --git a/Documentation/cxl/cxl-free-dpa.txt b/Documentation/cxl/cxl-free-dpa.txt

new file mode 100644

index 0000000..73fb048

--- /dev/null

+++ b/Documentation/cxl/cxl-free-dpa.txt

@@ -0,0 +1,53 @@

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

+

+cxl-free-dpa(1)

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

+

+NAME

+----

+cxl-free-dpa - release device-physical address space

+

+SYNOPSIS

+--------

+[verse]

+'cxl free-dpa' <mem0> [<mem1>..<memN>] [<options>]

+

+The CXL region provisioning process proceeds in multiple steps. One of

+the steps is identifying and reserving the DPA span that each member of

+the interleave-set (region) contributes in advance of attaching that

+allocation to a region. For development, test, and debug purposes this

+command is a helper to find the last allocated decoder on a device and

+zero-out / free its DPA allocation.

+

+OPTIONS

+-------

+<memory device(s)>::

+include::memdev-option.txt[]

+

+-d::

+--decoder::

+	Specify the decoder to free. The CXL specification

+	mandates that DPA must be released in the reverse order it was

+	allocated. See linkcxl:cxl-reserve-dpa[1]

+

+-t::

+--type::

+	Constrain the search for "last allocated decoder" to decoders targeting

+	the given partition.

+

+-f::

+--force::

+	The kernel enforces CXL DPA ordering constraints on deallocation events,

+	and the tool anticipates those and fails operations that are expected to

+	fail without sending them to the kernel. For test purposes, continue to

+	attempt "expected to fail" operations to exercise the driver.

+

+-v::

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

+	logging and debug enabled).

+

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

+

+SEE ALSO

+--------

+linkcxl:cxl-reserve-dpa[1]

diff --git a/Documentation/cxl/cxl-reserve-dpa.txt b/Documentation/cxl/cxl-reserve-dpa.txt

new file mode 100644

index 0000000..5e79ef2

--- /dev/null

+++ b/Documentation/cxl/cxl-reserve-dpa.txt

@@ -0,0 +1,67 @@

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

+

+cxl-reserve-dpa(1)

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

+

+NAME

+----

+cxl-reserve-dpa - allocate device-physical address space

+

+SYNOPSIS

+--------

+[verse]

+'cxl reserve-dpa' <mem0> [<mem1>..<memN>] [<options>]

+

+The CXL region provisioning process proceeds in multiple steps. One of

+the steps is identifying and reserving the DPA span that each member of

+the interleave-set (region) contributes in advance of attaching that

+allocation to a region. For development, test, and debug purposes this

+command is a helper to find the next available decoder on endpoint

+(memdev) and mark a span of DPA as busy.

+

+OPTIONS

+-------

+<memory device(s)>::

+include::memdev-option.txt[]

+

+-d::

+--decoder::

+	Specify the decoder to attempt the allocation. The CXL specification

+	mandates that allocations must be ordered by DPA and decoder instance.

+	I.e. the lowest DPA allocation on the device is covered by decoder0, and

+	the last / highest DPA allocation is covered by the last decoder. This

+	ordering is enforced by the kernel. By default the tool picks the 'next

+	available' decoder.

+

+-t::

+--type::

+	Select the partition for the allocation. CXL devices implement a

+	partition that divdes 'ram' and 'pmem' capacity, where 'pmem' capacity

+	consumes the higher DPA capacity above the partition boundary. The type

+	defaults to 'pmem'. Note that given CXL DPA allocation constraints, once

+	any 'pmem' allocation is established then all remaining 'ram' capacity

+	becomes reserved (skipped).

+

+-f::

+--force::

+	The kernel enforces CXL DPA allocation ordering constraints, and

+	the tool anticipates those and fails operations that are expected to

+	fail without sending them to the kernel. For test purposes, continue to

+	attempt "expected to fail" operations to exercise the driver.

+

+-s::

+--size::

+	Specify the size of the allocation. This option supports the suffixes

+	"k" or "K" for KiB, "m" or "M" for MiB, "g" or "G" for GiB and "t" or

+	"T" for TiB. This defaults to "all available capacity of the specified

+	type".

+

+-v::

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

+	logging and debug enabled).

+

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

+

+SEE ALSO

+--------

+linkcxl:cxl-free-dpa[1]

diff --git a/Documentation/cxl/lib/libcxl.txt b/Documentation/cxl/lib/libcxl.txt

index 90fe338..7a38ce4 100644

--- a/Documentation/cxl/lib/libcxl.txt

+++ b/Documentation/cxl/lib/libcxl.txt

@@ -394,6 +394,7 @@ unsigned long long cxl_decoder_get_resource(struct cxl_decoder *decoder);

 unsigned long long cxl_decoder_get_size(struct cxl_decoder *decoder);

 unsigned long long cxl_decoder_get_dpa_resource(struct cxl_decoder *decoder);

 unsigned long long cxl_decoder_get_dpa_size(struct cxl_decoder *decoder);

+int cxl_decoder_set_dpa_size(struct cxl_decoder *decoder, unsigned long long size);

 const char *cxl_decoder_get_devname(struct cxl_decoder *decoder);

 int cxl_decoder_get_id(struct cxl_decoder *decoder);

 int cxl_decoder_get_nr_targets(struct cxl_decoder *decoder);

@@ -413,6 +414,7 @@ enum cxl_decoder_mode {

 	CXL_DECODER_MODE_RAM,

 };

 enum cxl_decoder_mode cxl_decoder_get_mode(struct cxl_decoder *decoder);

+int cxl_decoder_set_mode(struct cxl_decoder *decoder, enum cxl_decoder_mode mode);

 bool cxl_decoder_is_pmem_capable(struct cxl_decoder *decoder);

 bool cxl_decoder_is_volatile_capable(struct cxl_decoder *decoder);

diff --git a/Documentation/cxl/meson.build b/Documentation/cxl/meson.build

index 974a5a4..d019dfc 100644

--- a/Documentation/cxl/meson.build

+++ b/Documentation/cxl/meson.build

@@ -36,6 +36,8 @@ cxl_manpages = [

   'cxl-disable-port.txt',

   'cxl-disable-bus.txt',

   'cxl-set-partition.txt',

+  'cxl-reserve-dpa.txt',

+  'cxl-free-dpa.txt',

 ]

 foreach man : cxl_manpages

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

index a437bc3..9e6fc62 100644

--- a/cxl/builtin.h

+++ b/cxl/builtin.h

@@ -12,6 +12,8 @@ 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);

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

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

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

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

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

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

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

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

index aa4ce61..ef4cda9 100644

--- a/cxl/cxl.c

+++ b/cxl/cxl.c

@@ -66,6 +66,8 @@ static struct cmd_struct commands[] = {

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

 	{ "disable-memdev", .c_fn = cmd_disable_memdev },

 	{ "enable-memdev", .c_fn = cmd_enable_memdev },

+	{ "reserve-dpa", .c_fn = cmd_reserve_dpa },

+	{ "free-dpa", .c_fn = cmd_free_dpa },

 	{ "disable-port", .c_fn = cmd_disable_port },

 	{ "enable-port", .c_fn = cmd_enable_port },

 	{ "set-partition", .c_fn = cmd_set_partition },

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

index 2f88a9d..e5fab19 100644

--- a/cxl/filter.c

+++ b/cxl/filter.c

@@ -380,8 +380,8 @@ struct cxl_port *util_cxl_port_filter_by_memdev(struct cxl_port *port,

 	return NULL;

 }

-static struct cxl_decoder *util_cxl_decoder_filter(struct cxl_decoder *decoder,

-						   const char *__ident)

+struct cxl_decoder *util_cxl_decoder_filter(struct cxl_decoder *decoder,

+					    const char *__ident)

 {

 	struct cxl_port *port = cxl_decoder_get_port(decoder);

 	int pid, did;

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

index 9557943..c913daf 100644

--- a/cxl/filter.h

+++ b/cxl/filter.h

@@ -50,6 +50,8 @@ struct cxl_target *util_cxl_target_filter_by_memdev(struct cxl_target *target,

 struct cxl_dport *util_cxl_dport_filter_by_memdev(struct cxl_dport *dport,

 						  const char *ident,

 						  const char *serial);

+struct cxl_decoder *util_cxl_decoder_filter(struct cxl_decoder *decoder,

+					    const char *__ident);

 int cxl_filter_walk(struct cxl_ctx *ctx, struct cxl_filter_params *param);

 bool cxl_filter_has(const char *needle, const char *__filter);

 #endif /* _CXL_UTIL_FILTER_H_ */

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

index b802e5d..e52896f 100644

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

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

@@ -1121,6 +1121,20 @@ CXL_EXPORT struct cxl_decoder *cxl_decoder_get_next(struct cxl_decoder *decoder)

 	return list_next(&port->decoders, decoder, list);

 }

+CXL_EXPORT struct cxl_decoder *cxl_decoder_get_last(struct cxl_port *port)

+{

+	cxl_decoders_init(port);

+

+	return list_tail(&port->decoders, struct cxl_decoder, list);

+}

+

+CXL_EXPORT struct cxl_decoder *cxl_decoder_get_prev(struct cxl_decoder *decoder)

+{

+	struct cxl_port *port = decoder->port;

+

+	return list_prev(&port->decoders, decoder, list);

+}

+

 CXL_EXPORT struct cxl_ctx *cxl_decoder_get_ctx(struct cxl_decoder *decoder)

 {

 	return decoder->ctx;

@@ -1176,6 +1190,78 @@ cxl_decoder_get_dpa_size(struct cxl_decoder *decoder)

 	return decoder->dpa_size;

 }

+CXL_EXPORT int cxl_decoder_set_dpa_size(struct cxl_decoder *decoder,

+					unsigned long long size)

+{

+	struct cxl_port *port = cxl_decoder_get_port(decoder);

+	struct cxl_ctx *ctx = cxl_decoder_get_ctx(decoder);

+	char *path = decoder->dev_buf;

+	int len = decoder->buf_len, rc;

+	char buf[SYSFS_ATTR_SIZE];

+

+	if (!cxl_port_is_endpoint(port)) {

+		err(ctx, "%s: not an endpoint decoder\n",

+		    cxl_decoder_get_devname(decoder));

+		return -EINVAL;

+	}

+

+	if (snprintf(path, len, "%s/dpa_size", decoder->dev_path) >= len) {

+		err(ctx, "%s: buffer too small!\n",

+		    cxl_decoder_get_devname(decoder));

+		return -ENOMEM;

+	}

+

+	sprintf(buf, "%#llx\n", size);

+	rc = sysfs_write_attr(ctx, path, buf);

+	if (rc < 0)

+		return rc;

+

+	decoder->dpa_size = size;

+	return 0;

+}

+

+CXL_EXPORT int cxl_decoder_set_mode(struct cxl_decoder *decoder,

+				    enum cxl_decoder_mode mode)

+{

+	struct cxl_port *port = cxl_decoder_get_port(decoder);

+	struct cxl_ctx *ctx = cxl_decoder_get_ctx(decoder);

+	char *path = decoder->dev_buf;

+	int len = decoder->buf_len, rc;

+	char buf[SYSFS_ATTR_SIZE];

+

+	if (!cxl_port_is_endpoint(port)) {

+		err(ctx, "%s: not an endpoint decoder\n",

+		    cxl_decoder_get_devname(decoder));

+		return -EINVAL;

+	}

+

+	switch (mode) {

+	case CXL_DECODER_MODE_PMEM:

+		sprintf(buf, "pmem");

+		break;

+	case CXL_DECODER_MODE_RAM:

+		sprintf(buf, "ram");

+		break;

+	default:

+		err(ctx, "%s: unsupported mode: %d\n",

+		    cxl_decoder_get_devname(decoder), mode);

+		return -EINVAL;

+	}

+

+	if (snprintf(path, len, "%s/mode", decoder->dev_path) >= len) {

+		err(ctx, "%s: buffer too small!\n",

+		    cxl_decoder_get_devname(decoder));

+		return -ENOMEM;

+	}

+

+	rc = sysfs_write_attr(ctx, path, buf);

+	if (rc < 0)

+		return rc;

+

+	decoder->mode = mode;

+	return 0;

+}

+

 CXL_EXPORT enum cxl_decoder_mode

 cxl_decoder_get_mode(struct cxl_decoder *decoder)

 {

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

index 88c5a7e..7712de0 100644

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

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

@@ -173,4 +173,8 @@ global:

 	cxl_decoder_get_dpa_resource;

 	cxl_decoder_get_dpa_size;

 	cxl_decoder_get_mode;

+	cxl_decoder_get_last;

+	cxl_decoder_get_prev;

+	cxl_decoder_set_dpa_size;

+	cxl_decoder_set_mode;

 } LIBCXL_2;

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

index 1436dc4..33a216e 100644

--- a/cxl/libcxl.h

+++ b/cxl/libcxl.h

@@ -139,6 +139,7 @@ enum cxl_decoder_mode {

 	CXL_DECODER_MODE_PMEM,

 	CXL_DECODER_MODE_RAM,

 };

+

 static inline const char *cxl_decoder_mode_name(enum cxl_decoder_mode mode)

 {

 	static const char *names[] = {

@@ -154,6 +155,10 @@ static inline const char *cxl_decoder_mode_name(enum cxl_decoder_mode mode)

 }

 enum cxl_decoder_mode cxl_decoder_get_mode(struct cxl_decoder *decoder);

+int cxl_decoder_set_mode(struct cxl_decoder *decoder,

+			 enum cxl_decoder_mode mode);

+int cxl_decoder_set_dpa_size(struct cxl_decoder *decoder,

+			     unsigned long long size);

 const char *cxl_decoder_get_devname(struct cxl_decoder *decoder);

 struct cxl_target *cxl_decoder_get_target_by_memdev(struct cxl_decoder *decoder,

 						    struct cxl_memdev *memdev);

@@ -182,6 +187,10 @@ bool cxl_decoder_is_locked(struct cxl_decoder *decoder);

 	for (decoder = cxl_decoder_get_first(port); decoder != NULL;           \

 	     decoder = cxl_decoder_get_next(decoder))

+#define cxl_decoder_foreach_reverse(port, decoder)                             \

+	for (decoder = cxl_decoder_get_last(port); decoder != NULL;           \

+	     decoder = cxl_decoder_get_prev(decoder))

+

 struct cxl_target;

 struct cxl_target *cxl_target_get_first(struct cxl_decoder *decoder);

 struct cxl_target *cxl_target_get_next(struct cxl_target *target);

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

index 1cecad2..e42f554 100644

--- a/cxl/memdev.c

+++ b/cxl/memdev.c

@@ -33,6 +33,7 @@ static struct parameters {

 	bool align;

 	const char *type;

 	const char *size;

+	const char *decoder_filter;

 } param;

 static struct log_ctx ml;

@@ -71,6 +72,19 @@ OPT_STRING('s', "size",  &param.size, "size",			\

 OPT_BOOLEAN('a', "align",  &param.align,			\

 	"auto-align --size per device's requirement")

+#define RESERVE_DPA_OPTIONS()                                          \

+OPT_STRING('s', "size", &param.size, "size",                           \

+	   "size in bytes (Default: all available capacity)")

+

+#define DPA_OPTIONS()                                          \

+OPT_STRING('d', "decoder", &param.decoder_filter,              \

+   "decoder instance id",                                      \

+   "override the automatic decoder selection"),                \

+OPT_STRING('t', "type", &param.type, "type",                   \

+	   "'pmem' or 'ram' (volatile) (Default: 'pmem')"),    \

+OPT_BOOLEAN('f', "force", &param.force,                        \

+	    "Attempt 'expected to fail' operations")

+

 static const struct option read_options[] = {

 	BASE_OPTIONS(),

 	LABEL_OPTIONS(),

@@ -108,6 +122,242 @@ static const struct option set_partition_options[] = {

 	OPT_END(),

 };

+static const struct option reserve_dpa_options[] = {

+	BASE_OPTIONS(),

+	RESERVE_DPA_OPTIONS(),

+	DPA_OPTIONS(),

+	OPT_END(),

+};

+

+static const struct option free_dpa_options[] = {

+	BASE_OPTIONS(),

+	DPA_OPTIONS(),

+	OPT_END(),

+};

+

+enum reserve_dpa_mode {

+	DPA_ALLOC,

+	DPA_FREE,

+};

+

+static int __reserve_dpa(struct cxl_memdev *memdev,

+			 enum reserve_dpa_mode alloc_mode,

+			 struct action_context *actx)

+{

+	struct cxl_decoder *decoder, *auto_target = NULL, *target = NULL;

+	struct cxl_endpoint *endpoint = cxl_memdev_get_endpoint(memdev);

+	const char *devname = cxl_memdev_get_devname(memdev);

+	unsigned long long avail_dpa, size;

+	enum cxl_decoder_mode mode;

+	struct cxl_port *port;

+	char buf[256];

+	int rc;

+

+	if (param.type) {

+		if (strcmp(param.type, "ram") == 0)

+			mode = CXL_DECODER_MODE_RAM;

+		else if (strcmp(param.type, "volatile") == 0)

+			mode = CXL_DECODER_MODE_RAM;

+		else if (strcmp(param.type, "ram") == 0)

+			mode = CXL_DECODER_MODE_RAM;

+		else if (strcmp(param.type, "pmem") == 0)

+			mode = CXL_DECODER_MODE_PMEM;

+		else {

+			log_err(&ml, "%s: unsupported type: %s\n", devname,

+				param.type);

+			return -EINVAL;

+		}

+	} else

+		mode = CXL_DECODER_MODE_RAM;

+

+	if (!endpoint) {

+		log_err(&ml, "%s: CXL operation disabled\n", devname);

+		return -ENXIO;

+	}

+

+	port = cxl_endpoint_get_port(endpoint);

+

+	if (mode == CXL_DECODER_MODE_RAM)

+		avail_dpa = cxl_memdev_get_ram_size(memdev);

+	else

+		avail_dpa = cxl_memdev_get_pmem_size(memdev);

+

+	cxl_decoder_foreach(port, decoder) {

+		size = cxl_decoder_get_dpa_size(decoder);

+		if (size == ULLONG_MAX)

+			continue;

+		if (cxl_decoder_get_mode(decoder) != mode)

+			continue;

+

+		if (size > avail_dpa) {

+			log_err(&ml, "%s: capacity accounting error\n",

+				devname);

+			return -ENXIO;

+		}

+		avail_dpa -= size;

+	}

+

+	if (!param.size)

+		if (alloc_mode == DPA_ALLOC) {

+			size = avail_dpa;

+			if (!avail_dpa) {

+				log_err(&ml, "%s: no available capacity\n",

+					devname);

+				return -ENOSPC;

+			}

+		} else

+			size = 0;

+	else {

+		size = parse_size64(param.size);

+		if (size == ULLONG_MAX) {

+			log_err(&ml, "%s: failed to parse size option '%s'\n",

+				devname, param.size);

+			return -EINVAL;

+		}

+		if (size > avail_dpa) {

+			log_err(&ml, "%s: '%s' exceeds available capacity\n",

+				devname, param.size);

+			if (!param.force)

+				return -ENOSPC;

+		}

+	}

+

+	/*

+	 * Find next free decoder, assumes cxl_decoder_foreach() is in

+	 * hardware instance-id order

+	 */

+	if (alloc_mode == DPA_ALLOC)

+		cxl_decoder_foreach(port, decoder) {

+			/* first 0-dpa_size is our target */

+			if (cxl_decoder_get_dpa_size(decoder) == 0) {

+				auto_target = decoder;

+				break;

+			}

+		}

+	else

+		cxl_decoder_foreach_reverse(port, decoder) {

+			/* nothing to free? */

+			if (!cxl_decoder_get_dpa_size(decoder))

+				continue;

+			/*

+			 * Active decoders can't be freed, and by definition all

+			 * previous decoders must also be active

+			 */

+			if (cxl_decoder_get_size(decoder))

+				break;

+			/* first dpa_size > 0 + disabled decoder is our target */

+			if (cxl_decoder_get_dpa_size(decoder) < ULLONG_MAX) {

+				auto_target = decoder;

+				break;

+			}

+		}

+

+	if (param.decoder_filter) {

+		unsigned long id;

+		char *end;

+

+		id = strtoul(param.decoder_filter, &end, 0);

+		/* allow for standalone ordinal decoder ids */

+		if (*end == '\0')

+			rc = snprintf(buf, sizeof(buf), "decoder%d.%ld",

+				      cxl_port_get_id(port), id);

+		else

+			rc = snprintf(buf, sizeof(buf), "%s",

+				      param.decoder_filter);

+

+		if (rc >= (int)sizeof(buf)) {

+			log_err(&ml, "%s: decoder filter '%s' too long\n",

+				devname, param.decoder_filter);

+			return -EINVAL;

+		}

+

+		if (alloc_mode == DPA_ALLOC)

+			cxl_decoder_foreach(port, decoder) {

+				target = util_cxl_decoder_filter(decoder, buf);

+				if (target)

+					break;

+			}

+		else

+			cxl_decoder_foreach_reverse(port, decoder) {

+				target = util_cxl_decoder_filter(decoder, buf);

+				if (target)

+					break;

+			}

+

+		if (!target) {

+			log_err(&ml, "%s: no match for decoder: '%s'\n",

+				devname, param.decoder_filter);

+			return -ENXIO;

+		}

+

+		if (target != auto_target) {

+			log_err(&ml, "%s: %s is out of sequence\n", devname,

+				cxl_decoder_get_devname(target));

+			if (!param.force)

+				return -EINVAL;

+		}

+	}

+

+	if (!target)

+		target = auto_target;

+

+	if (!target) {

+		log_err(&ml, "%s: no suitable decoder found\n", devname);

+		return -ENXIO;

+	}

+

+	if (cxl_decoder_get_mode(target) != mode) {

+		rc = cxl_decoder_set_dpa_size(target, 0);

+		if (rc) {

+			log_err(&ml,

+				"%s: %s: failed to clear allocation to set mode\n",

+				devname, cxl_decoder_get_devname(target));

+			return rc;

+		}

+		rc = cxl_decoder_set_mode(target, mode);

+		if (rc) {

+			log_err(&ml, "%s: %s: failed to set %s mode\n", devname,

+				cxl_decoder_get_devname(target),

+				mode == CXL_DECODER_MODE_PMEM ? "pmem" : "ram");

+			return rc;

+		}

+	}

+

+	rc = cxl_decoder_set_dpa_size(target, size);

+	if (rc)

+		log_err(&ml, "%s: %s: failed to set dpa allocation\n", devname,

+			cxl_decoder_get_devname(target));

+	else {

+		struct json_object *jdev, *jdecoder;

+		unsigned long flags = 0;

+

+		if (actx->f_out == stdout && isatty(1))

+			flags |= UTIL_JSON_HUMAN;

+		jdev = util_cxl_memdev_to_json(memdev, flags);

+		jdecoder = util_cxl_decoder_to_json(target, flags);

+		if (!jdev || !jdecoder) {

+			json_object_put(jdev);

+			json_object_put(jdecoder);

+		} else {

+			json_object_object_add(jdev, "decoder", jdecoder);

+			json_object_array_add(actx->jdevs, jdev);

+		}

+	}

+	return rc;

+}

+

+static int action_reserve_dpa(struct cxl_memdev *memdev,

+			      struct action_context *actx)

+{

+	return __reserve_dpa(memdev, DPA_ALLOC, actx);

+}

+

+static int action_free_dpa(struct cxl_memdev *memdev,

+			   struct action_context *actx)

+{

+	return __reserve_dpa(memdev, DPA_FREE, actx);

+}

+

 static int action_disable(struct cxl_memdev *memdev, struct action_context *actx)

 {

 	if (!cxl_memdev_is_enabled(memdev))

@@ -452,7 +702,8 @@ static int memdev_action(int argc, const char **argv, struct cxl_ctx *ctx,

 		err++;

 	}

-	if (action == action_setpartition)

+	if (action == action_setpartition || action == action_reserve_dpa ||

+	    action == action_free_dpa)

 		actx.jdevs = json_object_new_array();

 	if (err == argc) {

@@ -495,6 +746,8 @@ static int memdev_action(int argc, const char **argv, struct cxl_ctx *ctx,

 	count = 0;

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

+		bool found = false;

+

 		cxl_memdev_foreach(ctx, memdev) {

 			const char *memdev_filter = NULL;

 			const char *serial_filter = NULL;

@@ -507,6 +760,7 @@ static int memdev_action(int argc, const char **argv, struct cxl_ctx *ctx,

 			if (!util_cxl_memdev_filter(memdev, memdev_filter,