From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.14]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A0B8D351C2D; Fri, 29 May 2026 23:42:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.14 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780098173; cv=none; b=K8wCVM30wjwzkXY3P7Etq8zQIdRE1pziNdt9nTnt1xFthVXFyOHZAvMbWLQrQWSgo5zucoEUykZB47d2Bz2Yz5t3Z1umvim2BneUX3r6zONQpjSzRLQjHWKDRdklQX5fiU+hXwnmPhdCwxKl3E9C6Qw8q0nP7s0CSgjZxVYEdJo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780098173; c=relaxed/simple; bh=w6BFF7lQSHnWbf420H1HiE41Mms91tclocXhGA+s0Ow=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=r+TkJuuO3Qzybnk+LC06i/cAOkHcM6YAxQiIjkNsjs9m6upfXD6nhgyGf5DvE5301bADCQJXaWhlOBrN8N76BrFBxfvujfuxpAoP5AzE8jyD3z059ANACU98BzLI/dRldM5h1lN8ZImzWDIP+mrphCsadVYYBDO7lK6TJNl10eI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=TcF84NTK; arc=none smtp.client-ip=198.175.65.14 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="TcF84NTK" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1780098170; x=1811634170; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=w6BFF7lQSHnWbf420H1HiE41Mms91tclocXhGA+s0Ow=; b=TcF84NTKCfGXbrULOdhOaz3H4yJiyb+PC22a9OzlmPvj0pC5vNKrsm7f kNUeOJiIScdeJrGj/4/TlEgiAwSHzA6dW4hlNrtUwzbO40uEXNcOAd/iX /FuF3nEWcEfsLHyAyZ1VGodanTRtN+6dUD1xwdCsLTtccuFmcWWmRHTwz ojoXvqQPNx4fm8HmwFv5kyF3V5UfsmiNjTOjyTaiCr46V6S4bBLNjPpcr zY5/iMYLfZZCSJRyizeO+7fjGPFNbZTQRBeKviWVwGhjj4BbpKEGU0qkh oBNJaDY3tZYpGMLysgGiG6RBFvwGfxG4aPgz6z4R3EBQ5mwFRuqpLYVUV Q==; X-CSE-ConnectionGUID: Qwc2OMLwQbWajB/NhYUbrw== X-CSE-MsgGUID: 7RjuMy11SpKQWKmNMf1DpQ== X-IronPort-AV: E=McAfee;i="6800,10657,11801"; a="84843482" X-IronPort-AV: E=Sophos;i="6.24,176,1774335600"; d="scan'208";a="84843482" Received: from fmviesa010.fm.intel.com ([10.60.135.150]) by orvoesa106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 May 2026 16:42:49 -0700 X-CSE-ConnectionGUID: VXLhcBeJTSe5lTedbghvMg== X-CSE-MsgGUID: eAlAMGbOTlay0cAIwwTfPQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.24,176,1774335600"; d="scan'208";a="238801662" Received: from gabaabhi-mobl2.amr.corp.intel.com (HELO [10.125.111.151]) ([10.125.111.151]) by fmviesa010-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 May 2026 16:42:47 -0700 Message-ID: Date: Fri, 29 May 2026 16:42:46 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v10 30/31] tools/testing/cxl: Add DC Regions to mock mem data To: Anisa Su , linux-cxl@vger.kernel.org, linux-kernel@vger.kernel.org Cc: nvdimm@lists.linux.dev, Dan Williams , Jonathan Cameron , Davidlohr Bueso , Vishal Verma , Ira Weiny , Alison Schofield , John Groves , Gregory Price , Ira Weiny , Anisa Su References: Content-Language: en-US From: Dave Jiang In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 5/23/26 2:43 AM, Anisa Su wrote: > From: Ira Weiny > > cxl_test provides a good way to ensure quick smoke and regression > testing. The complexity of Dynamic Capacity (DC) extent processing as > well as the complexity of DC-backed DAX regions can mostly be tested > through cxl_test. This includes management of DC regions and DAX > devices on those regions; the management of extent device lifetimes; > and the processing of DCD events. > > The only missing functionality from this test is actual interrupt > processing. > > Mock memory devices can easily mock DC information and manage fake > extent data. > > Define mock_dc_partition information within the mock memory data. Add > sysfs entries on the mock device to inject and delete extents. > > The inject format is :::[:] where > is a UUID string (or "" / "0" for the null UUID) and is an > optional shared_extn_seq value used for sharable-partition tests > (defaults to 0). > The delete format is :: > > Directly call the event irq callback to simulate irqs to process the > test extents. > > Add DC mailbox commands to the CEL and implement those commands. > > Signed-off-by: Ira Weiny > Signed-off-by: Anisa Su > > --- > Changes: > [anisa: add uuid + shared_extn_seq, align mock with kernel validators, > introduce a sharable-partition test fixture] > [anisa: replace "sparse" terminology with "DC" / "DC-backed"] > > Carry a uuid_t and a u16 shared_extn_seq on each mock extent, parse > tags via uuid_parse() in the inject path and the pre-extent fixture, > and propagate both fields through log_dc_event() and > mock_get_dc_extent_list(). An optional 5th field in the inject > format supplies the shared_extn_seq for sharable-partition tests. > The delete format takes the uuid as its third field so release > events carry tag identity to the host. > > Mock fixes required to satisfy the host-side validators: > > - dsmad_handle starts at 0xFA, not 0xFADE. The Get Dynamic > Capacity Configuration response's DSMAD Handle field is 1 byte > per the CXL spec; the kernel rejects any handle with the upper > 24 bits non-zero as a firmware-bug. > > - dc_accept_extent() treats a re-accept of an already-accepted > extent as a successful no-op (look up dc_accepted_exts when the > sent xa lookup misses). The host replays accepts for pre- > injected extents on region creation; without this the existing- > extent ingest aborts with -ENOMEM. > > - __dc_del_extent_store() runs strim() on the trailing uuid field > so the ' > ' shell write tail doesn't cause parse_tag() to fall > through to uuid_parse() and -EINVAL. > > - NUM_MOCK_DC_REGIONS reduced from 2 to 1. The host's > cxl_dev_dc_identify() surfaces partitions[0] only, so extents > seeded into a second mock partition land outside the registered > DC range; for tagged groups that also trips the partition- > equality gate and drops the whole group (including the in-range > member). > > Sharable-partition test fixture: > > - Stamp MOCK_DC_SHARABLE_SERIAL (0xDCDC) on the cxl_mem instance > at pdev->id == 0. The companion cxl_test driver checks this > serial in mock_cxl_endpoint_parse_cdat() and sets the DC > partition's perf.shareable on that memdev only — exposing both > sharable and non-sharable DC partitions from one cxl_test > module load so the userspace suite can exercise both regimes. > > - Skip inject_prev_extents() on that one memdev: the pre-injected > extents are untagged / seq=0 and would be rejected as firmware- > bug by cxl_validate_extent() on a sharable partition, leaving > spurious noise in dmesg at probe. > --- > tools/testing/cxl/test/cxl.c | 21 + > tools/testing/cxl/test/mem.c | 806 ++++++++++++++++++++++++++++++++++- > 2 files changed, 826 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/cxl/test/cxl.c b/tools/testing/cxl/test/cxl.c > index 418669927fb0..ac6060ede061 100644 > --- a/tools/testing/cxl/test/cxl.c > +++ b/tools/testing/cxl/test/cxl.c > @@ -18,6 +18,15 @@ static int interleave_arithmetic; > static bool extended_linear_cache; > static bool fail_autoassemble; > > +/* > + * Mock serial sentinel. The cxl_mock_mem probe stamps this serial on > + * exactly one platform device (cxl_mem with id 0); that single memdev's > + * DC partition is marked sharable below in mock_cxl_endpoint_parse_cdat > + * so the suite can exercise sharable-extent code paths without losing > + * the non-sharable coverage on the other mock memdevs. > + */ > +#define MOCK_DC_SHARABLE_SERIAL 0xDCDCULL This is defined in cxl.c and mem.c. Why not just put it in a shared header? > + > #define FAKE_QTG_ID 42 > > #define NR_CXL_HOST_BRIDGES 2 > @@ -1432,6 +1441,18 @@ static void mock_cxl_endpoint_parse_cdat(struct cxl_port *port) > }; > > dpa_perf_setup(port, &range, perf); > + > + /* > + * The mock probe stamps MOCK_DC_SHARABLE_SERIAL onto exactly > + * one cxl_mem instance; mark its DC partition sharable so > + * cxl_validate_extent() routes shared-seq injects through > + * the sharable regime. Every other memdev keeps its DC > + * partition non-sharable so the existing untagged / seq=0 > + * tests still run on this kernel. > + */ > + if (cxlds->part[i].mode == CXL_PARTMODE_DYNAMIC_RAM_A && > + cxlds->serial == MOCK_DC_SHARABLE_SERIAL) > + perf->shareable = true; > } > > cxl_memdev_update_perf(cxlmd); > diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c > index fe1dadddd18e..9cc97b718b5f 100644 > --- a/tools/testing/cxl/test/mem.c > +++ b/tools/testing/cxl/test/mem.c > @@ -20,6 +20,7 @@ > #define FW_SLOTS 3 > #define DEV_SIZE SZ_2G > #define EFFECT(x) (1U << x) > +#define BASE_DYNAMIC_CAP_DPA DEV_SIZE > > #define MOCK_INJECT_DEV_MAX 8 > #define MOCK_INJECT_TEST_MAX 128 > @@ -113,6 +114,22 @@ static struct cxl_cel_entry mock_cel[] = { > EFFECT(SECURITY_CHANGE_IMMEDIATE) | > EFFECT(BACKGROUND_OP)), > }, > + { > + .opcode = cpu_to_le16(CXL_MBOX_OP_GET_DC_CONFIG), > + .effect = CXL_CMD_EFFECT_NONE, > + }, > + { > + .opcode = cpu_to_le16(CXL_MBOX_OP_GET_DC_EXTENT_LIST), > + .effect = CXL_CMD_EFFECT_NONE, > + }, > + { > + .opcode = cpu_to_le16(CXL_MBOX_OP_ADD_DC_RESPONSE), > + .effect = cpu_to_le16(EFFECT(CONF_CHANGE_IMMEDIATE)), > + }, > + { > + .opcode = cpu_to_le16(CXL_MBOX_OP_RELEASE_DC), > + .effect = cpu_to_le16(EFFECT(CONF_CHANGE_IMMEDIATE)), > + }, > }; > > /* See CXL 2.0 Table 181 Get Health Info Output Payload */ > @@ -173,6 +190,16 @@ struct vendor_test_feat { > __le32 data; > } __packed; > > +/* > + * The kernel surfaces only the first DC partition reported by the > + * device (cxl_dev_dc_identify() takes partitions[0] only), so any > + * extents we pre-inject into a second mock partition end up rejected > + * as "not in a valid DC partition" — and for tagged groups they also > + * trip the partition-equality gate and drop the whole group (including > + * the in-range member in DC0). Keep the mock at one DC partition. > + */ > +#define NUM_MOCK_DC_REGIONS 1 > + > struct cxl_mockmem_data { > void *lsa; > void *fw; > @@ -191,6 +218,20 @@ struct cxl_mockmem_data { > unsigned long sanitize_timeout; > struct vendor_test_feat test_feat; > u8 shutdown_state; > + > + struct cxl_dc_partition dc_partitions[NUM_MOCK_DC_REGIONS]; > + u32 dc_ext_generation; > + struct mutex ext_lock; > + > + /* > + * Extents are in 1 of 3 states > + * FM (sysfs added but not sent to the host yet) > + * sent (sent to the host but not accepted) > + * accepted (by the host) > + */ > + struct xarray dc_fm_extents; > + struct xarray dc_sent_extents; > + struct xarray dc_accepted_exts; > }; > > static struct mock_event_log *event_find_log(struct device *dev, int log_type) > @@ -607,6 +648,229 @@ static void cxl_mock_event_trigger(struct device *dev) > cxl_mem_get_event_records(mdata->mds, mes->ev_status); > } > > +struct cxl_extent_data { > + u64 dpa_start; > + u64 length; > + uuid_t uuid; > + u16 shared_extn_seq; > + bool shared; > +}; > + > +/* > + * Parse a tag string into a uuid_t. Accepts the empty string and "0" > + * as shorthand for the null UUID; anything else must be a UUID string > + * uuid_parse() can understand. > + */ > +static int parse_tag(const char *tag, uuid_t *out) > +{ > + if (!tag || tag[0] == '\0' || strcmp(tag, "0") == 0) { > + uuid_copy(out, &uuid_null); > + return 0; > + } > + return uuid_parse(tag, out); > +} > + > +static int __devm_add_extent(struct device *dev, struct xarray *array, > + u64 start, u64 length, const char *tag, > + u16 shared_extn_seq, bool shared) > +{ > + struct cxl_extent_data *extent; > + int rc; > + > + extent = devm_kzalloc(dev, sizeof(*extent), GFP_KERNEL); > + if (!extent) > + return -ENOMEM; > + > + extent->dpa_start = start; > + extent->length = length; > + rc = parse_tag(tag, &extent->uuid); > + if (rc) { > + dev_err(dev, "Failed to parse tag '%s'\n", tag); > + devm_kfree(dev, extent); > + return rc; > + } > + extent->shared_extn_seq = shared_extn_seq; > + extent->shared = shared; > + > + if (xa_insert(array, start, extent, GFP_KERNEL)) { > + devm_kfree(dev, extent); > + dev_err(dev, "Failed xarry insert %#llx\n", start); > + return -EINVAL; > + } > + > + return 0; > +} > + > +static int devm_add_fm_extent(struct device *dev, u64 start, u64 length, > + const char *tag, u16 shared_extn_seq, bool shared) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + > + guard(mutex)(&mdata->ext_lock); > + return __devm_add_extent(dev, &mdata->dc_fm_extents, start, length, > + tag, shared_extn_seq, shared); > +} > + > +static int dc_accept_extent(struct device *dev, u64 start, u64 length) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + struct cxl_extent_data *ext; > + > + dev_dbg(dev, "Host accepting extent %#llx\n", start); > + mdata->dc_ext_generation++; Should this only happen after xa_load() succeeds and checked? > + > + lockdep_assert_held(&mdata->ext_lock); Maybe this should go above the increment above > + ext = xa_load(&mdata->dc_sent_extents, start); > + if (!ext || ext->length != length) { > + /* > + * The host may re-accept extents we already moved into the > + * accepted xarray (e.g. pre-injected extents replayed on > + * region creation). Treat that as a successful no-op so > + * the existing-extent ingest path doesn't abort. > + */ > + ext = xa_load(&mdata->dc_accepted_exts, start); > + if (ext && ext->length == length) > + return 0; > + dev_err(dev, "Extent %#llx-%#llx not found\n", > + start, start + length); > + return -ENOMEM; > + } > + xa_erase(&mdata->dc_sent_extents, start); > + return xa_insert(&mdata->dc_accepted_exts, start, ext, GFP_KERNEL); > +} > + > +static void release_dc_ext(void *md) > +{ > + struct cxl_mockmem_data *mdata = md; > + > + xa_destroy(&mdata->dc_fm_extents); > + xa_destroy(&mdata->dc_sent_extents); > + xa_destroy(&mdata->dc_accepted_exts); > +} > + > +/* Pretend to have some previous accepted extents */ > +struct pre_ext_info { > + u64 offset; > + u64 length; > + const char *tag; > +} pre_ext_info[] = { > + { > + .offset = SZ_128M, > + .length = SZ_64M, > + .tag = "", > + }, > + { > + .offset = SZ_256M, > + .length = SZ_64M, > + .tag = "deadbeef-cafe-baad-f00d-fedcba987654", > + }, > +}; > + > +static int devm_add_sent_extent(struct device *dev, u64 start, u64 length, > + const char *tag, u16 shared_extn_seq, bool shared) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + > + lockdep_assert_held(&mdata->ext_lock); > + return __devm_add_extent(dev, &mdata->dc_sent_extents, start, length, > + tag, shared_extn_seq, shared); > +} > + > +static int inject_prev_extents(struct device *dev, u64 base_dpa) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + int rc; > + > + dev_dbg(dev, "Adding %ld pre-extents for testing\n", > + ARRAY_SIZE(pre_ext_info)); > + > + guard(mutex)(&mdata->ext_lock); > + for (int i = 0; i < ARRAY_SIZE(pre_ext_info); i++) { > + u64 ext_dpa = base_dpa + pre_ext_info[i].offset; > + u64 ext_len = pre_ext_info[i].length; > + > + dev_dbg(dev, "Adding pre-extent DPA:%#llx LEN:%#llx tag:%s\n", > + ext_dpa, ext_len, pre_ext_info[i].tag); > + > + rc = devm_add_sent_extent(dev, ext_dpa, ext_len, > + pre_ext_info[i].tag, 0, false); > + if (rc) { > + dev_err(dev, "Failed to add pre-extent DPA:%#llx LEN:%#llx; %d\n", > + ext_dpa, ext_len, rc); > + return rc; > + } > + > + rc = dc_accept_extent(dev, ext_dpa, ext_len); > + if (rc) > + return rc; > + } > + return 0; > +} > + > +static int cxl_mock_dc_partition_setup(struct device *dev) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + u64 base_dpa = BASE_DYNAMIC_CAP_DPA; > + u32 dsmad_handle = 0xFA; > + u64 decode_length = SZ_512M; > + u64 block_size = SZ_512; > + u64 length = SZ_512M; > + int rc; > + > + mutex_init(&mdata->ext_lock); > + xa_init(&mdata->dc_fm_extents); > + xa_init(&mdata->dc_sent_extents); > + xa_init(&mdata->dc_accepted_exts); > + > + rc = devm_add_action_or_reset(dev, release_dc_ext, mdata); > + if (rc) > + return rc; > + > + for (int i = 0; i < NUM_MOCK_DC_REGIONS; i++) { > + struct cxl_dc_partition *part = &mdata->dc_partitions[i]; > + > + dev_dbg(dev, "Creating DC partition DC%d DPA:%#llx LEN:%#llx\n", > + i, base_dpa, length); > + > + part->base = cpu_to_le64(base_dpa); > + part->decode_length = cpu_to_le64(decode_length / > + CXL_CAPACITY_MULTIPLIER); > + part->length = cpu_to_le64(length); > + part->block_size = cpu_to_le64(block_size); > + part->dsmad_handle = cpu_to_le32(dsmad_handle); > + dsmad_handle++; > + > + /* > + * Skip pre-injection on the sharable mock memdev. The > + * pre-injected extents are untagged / seq=0, which a > + * sharable partition rejects as firmware-bug; leaving the > + * sharable memdev with an empty DC partition is what its > + * dedicated tests (test_shared_extent_inject and > + * test_seq_integrity_gap in cxl-dcd.sh) expect anyway. > + * > + * The sharable fixture is the memdev at pdev->id == 0 — > + * see the matching MOCK_DC_SHARABLE_SERIAL stamp in > + * cxl_mock_mem_probe(). This relies on tools/testing/cxl > + * always allocating a "cxl_mem" platform device with id 0 > + * as the first memdev; if that invariant ever breaks the > + * sharable test fixture will land on the wrong device. > + */ > + if (to_platform_device(dev)->id != 0) { > + rc = inject_prev_extents(dev, base_dpa); > + if (rc) { > + dev_err(dev, > + "Failed to add pre-extents for DC%d\n", > + i); > + return rc; > + } > + } > + > + base_dpa += decode_length; > + } > + > + return 0; > +} > + > static int mock_gsl(struct cxl_mbox_cmd *cmd) > { > if (cmd->size_out < sizeof(mock_gsl_payload)) > @@ -1582,6 +1846,193 @@ static int mock_get_supported_features(struct cxl_mockmem_data *mdata, > return 0; > } > > +static int mock_get_dc_config(struct device *dev, > + struct cxl_mbox_cmd *cmd) > +{ > + struct cxl_mbox_get_dc_config_in *dc_config = cmd->payload_in; > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + u8 partition_requested, partition_start_idx, partition_ret_cnt; > + struct cxl_mbox_get_dc_config_out *resp; > + int i; > + > + partition_requested = min(dc_config->partition_count, NUM_MOCK_DC_REGIONS); > + > + if (cmd->size_out < struct_size(resp, partition, partition_requested)) > + return -EINVAL; > + > + memset(cmd->payload_out, 0, cmd->size_out); > + resp = cmd->payload_out; > + > + partition_start_idx = dc_config->start_partition_index; > + partition_ret_cnt = 0; > + for (i = 0; i < NUM_MOCK_DC_REGIONS; i++) { > + if (i >= partition_start_idx) { Should there be a check for partition_requested and exit when reached? > + memcpy(&resp->partition[partition_ret_cnt], > + &mdata->dc_partitions[i], > + sizeof(resp->partition[partition_ret_cnt])); > + partition_ret_cnt++; > + } > + } > + resp->avail_partition_count = NUM_MOCK_DC_REGIONS; > + resp->partitions_returned = i; partition returned always return NUM_MOCK_DC_REGIONS. Never takes into account partition_start_idx. > + > + dev_dbg(dev, "Returning %d dc partitions\n", partition_ret_cnt); > + return 0; > +} > + > +static int mock_get_dc_extent_list(struct device *dev, > + struct cxl_mbox_cmd *cmd) > +{ > + struct cxl_mbox_get_extent_out *resp = cmd->payload_out; > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + struct cxl_mbox_get_extent_in *get = cmd->payload_in; > + u32 total_avail = 0, total_ret = 0; > + struct cxl_extent_data *ext; > + u32 ext_count, start_idx; > + unsigned long i; > + > + ext_count = le32_to_cpu(get->extent_cnt); > + start_idx = le32_to_cpu(get->start_extent_index); > + > + memset(resp, 0, sizeof(*resp)); > + > + guard(mutex)(&mdata->ext_lock); > + /* > + * Total available needs to be calculated and returned regardless of > + * how many can actually be returned. > + */ > + xa_for_each(&mdata->dc_accepted_exts, i, ext) > + total_avail++; > + > + if (start_idx > total_avail) > + return -EINVAL; > + > + xa_for_each(&mdata->dc_accepted_exts, i, ext) { > + if (total_ret >= ext_count) > + break; > + > + if (total_ret >= start_idx) { In the case where start_idx > 0, I think we hit an infinite loop. > + resp->extent[total_ret].start_dpa = > + cpu_to_le64(ext->dpa_start); > + resp->extent[total_ret].length = > + cpu_to_le64(ext->length); > + export_uuid(resp->extent[total_ret].uuid, &ext->uuid); > + resp->extent[total_ret].shared_extn_seq = > + cpu_to_le16(ext->shared_extn_seq); > + total_ret++; > + } > + } > + > + resp->returned_extent_count = cpu_to_le32(total_ret); > + resp->total_extent_count = cpu_to_le32(total_avail); > + resp->generation_num = cpu_to_le32(mdata->dc_ext_generation); > + > + dev_dbg(dev, "Returning %d extents of %d total\n", > + total_ret, total_avail); > + > + return 0; > +} > + > +static void dc_clear_sent(struct device *dev) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + struct cxl_extent_data *ext; > + unsigned long index; > + > + lockdep_assert_held(&mdata->ext_lock); > + > + /* Any extents not accepted must be cleared */ > + xa_for_each(&mdata->dc_sent_extents, index, ext) { > + dev_dbg(dev, "Host rejected extent %#llx\n", ext->dpa_start); > + xa_erase(&mdata->dc_sent_extents, ext->dpa_start); > + } > +} > + > +static int mock_add_dc_response(struct device *dev, > + struct cxl_mbox_cmd *cmd) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + struct cxl_mbox_dc_response *req = cmd->payload_in; > + u32 list_size = le32_to_cpu(req->extent_list_size); > + > + guard(mutex)(&mdata->ext_lock); > + for (int i = 0; i < list_size; i++) { > + u64 start = le64_to_cpu(req->extent_list[i].dpa_start); > + u64 length = le64_to_cpu(req->extent_list[i].length); > + int rc; > + > + rc = dc_accept_extent(dev, start, length); > + if (rc) > + return rc; > + } mock response seems to be missing ordering check. CXL r4.0 8.2.10.9.9.3 requires ADD_DC_RESPONSE to be sent in same order as the Add Capacity Event Records or return invalid input. > + > + dc_clear_sent(dev); > + return 0; > +} > + > +static void dc_delete_extent(struct device *dev, unsigned long long start, > + unsigned long long length) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + unsigned long long end = start + length; > + struct cxl_extent_data *ext; > + unsigned long index; > + > + dev_dbg(dev, "Deleting extent at %#llx len:%#llx\n", start, length); > + > + guard(mutex)(&mdata->ext_lock); > + xa_for_each(&mdata->dc_fm_extents, index, ext) { > + u64 extent_end = ext->dpa_start + ext->length; > + > + /* > + * Any extent which 'touches' the released delete range will be > + * removed. > + */ > + if ((start <= ext->dpa_start && ext->dpa_start < end) || > + (start <= extent_end && extent_end < end)) would this work? if (start < extent_end && ext->dpa_start < end) > + xa_erase(&mdata->dc_fm_extents, ext->dpa_start); > + } > + > + /* > + * If the extent was accepted let it be for the host to drop > + * later. > + */ > +} > + > +static int release_accepted_extent(struct device *dev, u64 start, u64 length) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + struct cxl_extent_data *ext; > + > + guard(mutex)(&mdata->ext_lock); > + ext = xa_load(&mdata->dc_accepted_exts, start); > + if (!ext || ext->length != length) { > + dev_err(dev, "Extent %#llx not in accepted state\n", start); > + return -EINVAL; > + } > + xa_erase(&mdata->dc_accepted_exts, start); > + mdata->dc_ext_generation++; > + > + return 0; > +} > + > +static int mock_dc_release(struct device *dev, > + struct cxl_mbox_cmd *cmd) > +{ > + struct cxl_mbox_dc_response *req = cmd->payload_in; > + u32 list_size = le32_to_cpu(req->extent_list_size); > + > + for (int i = 0; i < list_size; i++) { > + u64 start = le64_to_cpu(req->extent_list[i].dpa_start); > + u64 length = le64_to_cpu(req->extent_list[i].length); > + > + dev_dbg(dev, "Extent %#llx released by host\n", start); > + release_accepted_extent(dev, start, length); > + } > + > + return 0; > +} > + > static int cxl_mock_mbox_send(struct cxl_mailbox *cxl_mbox, > struct cxl_mbox_cmd *cmd) > { > @@ -1673,6 +2124,18 @@ static int cxl_mock_mbox_send(struct cxl_mailbox *cxl_mbox, > case CXL_MBOX_OP_GET_SUPPORTED_FEATURES: > rc = mock_get_supported_features(mdata, cmd); > break; > + case CXL_MBOX_OP_GET_DC_CONFIG: > + rc = mock_get_dc_config(dev, cmd); > + break; > + case CXL_MBOX_OP_GET_DC_EXTENT_LIST: > + rc = mock_get_dc_extent_list(dev, cmd); > + break; > + case CXL_MBOX_OP_ADD_DC_RESPONSE: > + rc = mock_add_dc_response(dev, cmd); > + break; > + case CXL_MBOX_OP_RELEASE_DC: > + rc = mock_dc_release(dev, cmd); > + break; > case CXL_MBOX_OP_GET_FEATURE: > rc = mock_get_feature(mdata, cmd); > break; > @@ -1739,6 +2202,14 @@ static void init_event_log(struct mock_event_log *log) > log->last_handle = 1; > } > > +/* > + * Stamp this serial on a single mock cxl_mem instance so the > + * companion cxl_test driver can find it and mark its DC partition > + * sharable in mock_cxl_endpoint_parse_cdat(). Must match the value > + * defined in tools/testing/cxl/test/cxl.c. > + */ > +#define MOCK_DC_SHARABLE_SERIAL 0xDCDCULL > + > static int cxl_mock_mem_probe(struct platform_device *pdev) > { > struct device *dev = &pdev->dev; > @@ -1758,6 +2229,10 @@ static int cxl_mock_mem_probe(struct platform_device *pdev) > return -ENOMEM; > dev_set_drvdata(dev, mdata); > > + rc = cxl_mock_dc_partition_setup(dev); > + if (rc) > + return rc; > + > mdata->lsa = vmalloc(LSA_SIZE); > if (!mdata->lsa) > return -ENOMEM; > @@ -1774,7 +2249,23 @@ static int cxl_mock_mem_probe(struct platform_device *pdev) > if (rc) > return rc; > > - mds = cxl_memdev_state_create(dev, pdev->id + 1, 0); > + { > + u64 serial = pdev->id + 1; > + > + /* > + * Reserve the memdev at pdev->id == 0 as the sharable DC > + * partition test fixture. This relies on tools/testing/cxl > + * always allocating a "cxl_mem" platform device with id 0 > + * as the first memdev — currently true in cxl.c, but if > + * the topology ever renumbers, the sharable serial will be > + * stamped on the wrong device (or no device). Matched by > + * the skip-pre-inject guard in cxl_mock_dc_partition_setup > + * and by mock_cxl_endpoint_parse_cdat in cxl_test. > + */ > + if (pdev->id == 0) > + serial = MOCK_DC_SHARABLE_SERIAL; > + mds = cxl_memdev_state_create(dev, serial, 0); > + } Would prefer not have inline anonymous block. Just declare the var at top. > if (IS_ERR(mds)) > return PTR_ERR(mds); > > @@ -1814,6 +2305,9 @@ static int cxl_mock_mem_probe(struct platform_device *pdev) > if (rc) > return rc; > > + if (cxl_dcd_supported(mds)) > + cxl_configure_dcd(mds, &range_info); > + > rc = cxl_dpa_setup(cxlds, &range_info); > if (rc) > return rc; > @@ -1921,11 +2415,321 @@ static ssize_t sanitize_timeout_store(struct device *dev, > > static DEVICE_ATTR_RW(sanitize_timeout); > > +/* Return if the proposed extent would break the test code */ > +static bool new_extent_valid(struct device *dev, size_t new_start, > + size_t new_len) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + struct cxl_extent_data *extent; > + size_t new_end, i; > + > + if (!new_len) > + return false; > + > + new_end = new_start + new_len; > + > + dev_dbg(dev, "New extent %zx-%zx\n", new_start, new_end); > + > + guard(mutex)(&mdata->ext_lock); > + dev_dbg(dev, "Checking extents starts...\n"); > + xa_for_each(&mdata->dc_fm_extents, i, extent) { > + if (extent->dpa_start == new_start) > + return false; > + } > + > + dev_dbg(dev, "Checking sent extents starts...\n"); > + xa_for_each(&mdata->dc_sent_extents, i, extent) { > + if (extent->dpa_start == new_start) > + return false; > + } > + > + dev_dbg(dev, "Checking accepted extents starts...\n"); > + xa_for_each(&mdata->dc_accepted_exts, i, extent) { > + if (extent->dpa_start == new_start) > + return false; > + } > + > + return true; > +} > + > +struct cxl_test_dcd { > + uuid_t id; > + struct cxl_event_dcd rec; > +} __packed; > + > +struct cxl_test_dcd dcd_event_rec_template = { > + .id = CXL_EVENT_DC_EVENT_UUID, > + .rec = { > + .hdr = { > + .length = sizeof(struct cxl_test_dcd), > + }, > + }, > +}; > + > +static int log_dc_event(struct cxl_mockmem_data *mdata, enum dc_event type, > + u64 start, u64 length, const char *tag_str, > + u16 shared_extn_seq, bool more) > +{ > + struct device *dev = mdata->mds->cxlds.dev; > + struct cxl_test_dcd *dcd_event; > + uuid_t tag; > + int rc; > + > + dev_dbg(dev, "mock device log event %d\n", type); > + > + dcd_event = devm_kmemdup(dev, &dcd_event_rec_template, > + sizeof(*dcd_event), GFP_KERNEL); > + if (!dcd_event) > + return -ENOMEM; > + > + dcd_event->rec.flags = 0; > + if (more) > + dcd_event->rec.flags |= CXL_DCD_EVENT_MORE; > + dcd_event->rec.event_type = type; > + dcd_event->rec.extent.start_dpa = cpu_to_le64(start); > + dcd_event->rec.extent.length = cpu_to_le64(length); > + rc = parse_tag(tag_str, &tag); > + if (rc) { > + devm_kfree(dev, dcd_event); > + return rc; > + } > + export_uuid(dcd_event->rec.extent.uuid, &tag); > + dcd_event->rec.extent.shared_extn_seq = cpu_to_le16(shared_extn_seq); > + > + mes_add_event(mdata, CXL_EVENT_TYPE_DCD, > + (struct cxl_event_record_raw *)dcd_event); > + > + /* Fake the irq */ > + cxl_mem_get_event_records(mdata->mds, CXLDEV_EVENT_STATUS_DCD); > + > + return 0; > +} > + > +static void mark_extent_sent(struct device *dev, unsigned long long start) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + struct cxl_extent_data *ext; > + > + guard(mutex)(&mdata->ext_lock); > + ext = xa_erase(&mdata->dc_fm_extents, start); > + if (xa_insert(&mdata->dc_sent_extents, ext->dpa_start, ext, GFP_KERNEL)) > + dev_err(dev, "Failed to mark extent %#llx sent\n", ext->dpa_start); Should it also clean up 'ext' since insert failed? DJ > +} > + > +/* > + * Format ::: > + * > + * start and length must be a multiple of the configured partition block size. > + * Tag can be any string up to 16 bytes. > + * > + * Extents must be exclusive of other extents > + * > + * If the more flag is specified it is expected that an additional extent will > + * be specified without the more flag to complete the test transaction with the > + * host. > + */ > +static ssize_t __dc_inject_extent_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t count, > + bool shared) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + unsigned long long start, length, more; > + char *len_str, *uuid_str, *more_str, *seq_str; > + u16 shared_extn_seq = 0; > + size_t buf_len = count; > + int rc; > + > + char *start_str __free(kfree) = kstrdup(buf, GFP_KERNEL); > + if (!start_str) > + return -ENOMEM; > + > + len_str = strnchr(start_str, buf_len, ':'); > + if (!len_str) { > + dev_err(dev, "Extent failed to find len_str: %s\n", start_str); > + return -EINVAL; > + } > + > + *len_str = '\0'; > + len_str += 1; > + buf_len -= strlen(start_str); > + > + uuid_str = strnchr(len_str, buf_len, ':'); > + if (!uuid_str) { > + dev_err(dev, "Extent failed to find uuid_str: %s\n", len_str); > + return -EINVAL; > + } > + *uuid_str = '\0'; > + uuid_str += 1; > + > + more_str = strnchr(uuid_str, buf_len, ':'); > + if (!more_str) { > + dev_err(dev, "Extent failed to find more_str: %s\n", uuid_str); > + return -EINVAL; > + } > + *more_str = '\0'; > + more_str += 1; > + > + /* Optional 5th field: shared_extn_seq. Absent -> 0. */ > + seq_str = strnchr(more_str, buf_len, ':'); > + if (seq_str) { > + unsigned long long seq; > + > + *seq_str = '\0'; > + seq_str += 1; > + if (kstrtoull(seq_str, 0, &seq) || seq > U16_MAX) { > + dev_err(dev, "Extent failed to parse seq: %s\n", > + seq_str); > + return -EINVAL; > + } > + shared_extn_seq = seq; > + } > + > + if (kstrtoull(start_str, 0, &start)) { > + dev_err(dev, "Extent failed to parse start: %s\n", start_str); > + return -EINVAL; > + } > + > + if (kstrtoull(len_str, 0, &length)) { > + dev_err(dev, "Extent failed to parse length: %s\n", len_str); > + return -EINVAL; > + } > + > + if (kstrtoull(more_str, 0, &more)) { > + dev_err(dev, "Extent failed to parse more: %s\n", more_str); > + return -EINVAL; > + } > + > + if (!new_extent_valid(dev, start, length)) > + return -EINVAL; > + > + rc = devm_add_fm_extent(dev, start, length, uuid_str, shared_extn_seq, > + shared); > + if (rc) { > + dev_err(dev, "Failed to add extent DPA:%#llx LEN:%#llx; %d\n", > + start, length, rc); > + return rc; > + } > + > + mark_extent_sent(dev, start); > + rc = log_dc_event(mdata, DCD_ADD_CAPACITY, start, length, uuid_str, > + shared_extn_seq, more); > + if (rc) { > + dev_err(dev, "Failed to add event %d\n", rc); > + return rc; > + } > + > + return count; > +} > + > +static ssize_t dc_inject_extent_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t count) > +{ > + return __dc_inject_extent_store(dev, attr, buf, count, false); > +} > +static DEVICE_ATTR_WO(dc_inject_extent); > + > +static ssize_t dc_inject_shared_extent_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t count) > +{ > + return __dc_inject_extent_store(dev, attr, buf, count, true); > +} > +static DEVICE_ATTR_WO(dc_inject_shared_extent); > + > +static ssize_t __dc_del_extent_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t count, > + enum dc_event type) > +{ > + struct cxl_mockmem_data *mdata = dev_get_drvdata(dev); > + unsigned long long start, length; > + char *len_str, *uuid_str; > + size_t buf_len = count; > + int rc; > + > + char *start_str __free(kfree) = kstrdup(buf, GFP_KERNEL); > + if (!start_str) > + return -ENOMEM; > + > + len_str = strnchr(start_str, buf_len, ':'); > + if (!len_str) { > + dev_err(dev, "Failed to find len_str: %s\n", start_str); > + return -EINVAL; > + } > + *len_str = '\0'; > + len_str += 1; > + buf_len -= strlen(start_str); > + > + uuid_str = strnchr(len_str, buf_len, ':'); > + if (!uuid_str) { > + dev_err(dev, "Failed to find uuid_str: %s\n", len_str); > + return -EINVAL; > + } > + *uuid_str = '\0'; > + uuid_str += 1; > + /* > + * uuid_str is the trailing field; trim shell-added '\n' so > + * parse_tag()/uuid_parse() see a clean string. > + */ > + uuid_str = strim(uuid_str); > + > + if (kstrtoull(start_str, 0, &start)) { > + dev_err(dev, "Failed to parse start: %s\n", start_str); > + return -EINVAL; > + } > + > + if (kstrtoull(len_str, 0, &length)) { > + dev_err(dev, "Failed to parse length: %s\n", len_str); > + return -EINVAL; > + } > + > + dc_delete_extent(dev, start, length); > + > + if (type == DCD_FORCED_CAPACITY_RELEASE) > + dev_dbg(dev, "Forcing delete of extent %#llx len:%#llx\n", > + start, length); > + > + rc = log_dc_event(mdata, type, start, length, uuid_str, 0, false); > + if (rc) { > + dev_err(dev, "Failed to add event %d\n", rc); > + return rc; > + } > + > + return count; > +} > + > +/* > + * Format :: > + */ > +static ssize_t dc_del_extent_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t count) > +{ > + return __dc_del_extent_store(dev, attr, buf, count, > + DCD_RELEASE_CAPACITY); > +} > +static DEVICE_ATTR_WO(dc_del_extent); > + > +static ssize_t dc_force_del_extent_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t count) > +{ > + return __dc_del_extent_store(dev, attr, buf, count, > + DCD_FORCED_CAPACITY_RELEASE); > +} > +static DEVICE_ATTR_WO(dc_force_del_extent); > + > static struct attribute *cxl_mock_mem_attrs[] = { > &dev_attr_security_lock.attr, > &dev_attr_event_trigger.attr, > &dev_attr_fw_buf_checksum.attr, > &dev_attr_sanitize_timeout.attr, > + &dev_attr_dc_inject_extent.attr, > + &dev_attr_dc_inject_shared_extent.attr, > + &dev_attr_dc_del_extent.attr, > + &dev_attr_dc_force_del_extent.attr, > NULL > }; > ATTRIBUTE_GROUPS(cxl_mock_mem);