From patchwork Tue Oct 17 05:44:55 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Verma, Vishal L" X-Patchwork-Id: 13424461 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.120]) (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 B0B3BC135 for ; Tue, 17 Oct 2023 05:45:08 +0000 (UTC) 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="eokZnalG" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1697521508; x=1729057508; h=from:date:subject:mime-version:content-transfer-encoding: message-id:references:in-reply-to:to:cc; bh=jE1m85E7fxIhhpuuUBH8EL0PB4Icod+o0o4Ao4dEZ0w=; b=eokZnalG4BmYEyPtX0g4tfpHkIoJCMJlCk2V9wKg2KD39gu2ig//YyEe 00wP8KxrsmD0ETeMmZh/HnwmkKNb+aCeDMVfM0ylY8kDOSxsTmL2x9lcs ODfTi2gDjEfUs3R1mxqrqNpQe29zCX1f+2e3LdFBsrTM/FcYNAsNisFWy 11mZ5PuxNleC+Sgcxfa87c5dEMVOpEs8aC1ew/mgeAAI1B7RVuTnHp+ly IFbtGGzS0CSHRY/kp0vLFUtx4L7ApTxMSwwwWg0QUUotoK1o0WitApUbF xm68I+y/l5+2Qsg3HBVIyLbX0RZAxvzzJLgXTL66To3wx3f0kw7lCLXeE A==; X-IronPort-AV: E=McAfee;i="6600,9927,10865"; a="384580757" X-IronPort-AV: E=Sophos;i="6.03,231,1694761200"; d="scan'208";a="384580757" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Oct 2023 22:45:06 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10865"; a="879694022" X-IronPort-AV: E=Sophos;i="6.03,231,1694761200"; d="scan'208";a="879694022" Received: from mjwirth-mobl.amr.corp.intel.com (HELO [192.168.1.200]) ([10.209.151.162]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Oct 2023 22:45:02 -0700 From: Vishal Verma Date: Mon, 16 Oct 2023 23:44:55 -0600 Subject: [PATCH v6 1/3] mm/memory_hotplug: replace an open-coded kmemdup() in add_memory_resource() Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20231016-vv-kmem_memmap-v6-1-078f0d3c0371@intel.com> References: <20231016-vv-kmem_memmap-v6-0-078f0d3c0371@intel.com> In-Reply-To: <20231016-vv-kmem_memmap-v6-0-078f0d3c0371@intel.com> To: Andrew Morton , David Hildenbrand , Oscar Salvador , Dan Williams , Dave Jiang Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, Huang Ying , Dave Hansen , "Aneesh Kumar K.V" , Michal Hocko , Jonathan Cameron , Jeff Moyer , Vishal Verma X-Mailer: b4 0.12.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=1311; i=vishal.l.verma@intel.com; h=from:subject:message-id; bh=jE1m85E7fxIhhpuuUBH8EL0PB4Icod+o0o4Ao4dEZ0w=; b=owGbwMvMwCXGf25diOft7jLG02pJDKl68jGKGn4bTxx1ebOqYNu6jh2vbXTSVs2Z/qryjOmFo KyTKpUmHaUsDGJcDLJiiix/93xkPCa3PZ8nMMERZg4rE8gQBi5OAZiIjgvDP8vfOR817jvMuqcp dK6592xXD8/HW2dSDdl9X3+bPs/AsZjhv5d+mfdFW7u/SxvW+W/I0nmkLHRYricuNbr191vtRba cTAA= X-Developer-Key: i=vishal.l.verma@intel.com; a=openpgp; fpr=F8682BE134C67A12332A2ED07AFA61BEA3B84DFF A review of the memmap_on_memory modifications to add_memory_resource() revealed an instance of an open-coded kmemdup(). Replace it with kmemdup(). Cc: Andrew Morton Cc: David Hildenbrand Cc: Michal Hocko Cc: Oscar Salvador Cc: Dan Williams Reported-by: Dan Williams Signed-off-by: Vishal Verma Reviewed-by: David Hildenbrand --- mm/memory_hotplug.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index f8d3e7427e32..6be7de9efa55 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1439,11 +1439,11 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags) if (mhp_flags & MHP_MEMMAP_ON_MEMORY) { if (mhp_supports_memmap_on_memory(size)) { mhp_altmap.free = memory_block_memmap_on_memory_pages(); - params.altmap = kmalloc(sizeof(struct vmem_altmap), GFP_KERNEL); + params.altmap = kmemdup(&mhp_altmap, + sizeof(struct vmem_altmap), + GFP_KERNEL); if (!params.altmap) goto error; - - memcpy(params.altmap, &mhp_altmap, sizeof(mhp_altmap)); } /* fallback to not using altmap */ } From patchwork Tue Oct 17 05:44:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Verma, Vishal L" X-Patchwork-Id: 13424462 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.120]) (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 1294BC153 for ; Tue, 17 Oct 2023 05:45:10 +0000 (UTC) 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="Wz7Y1Q6z" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1697521510; x=1729057510; h=from:date:subject:mime-version:content-transfer-encoding: message-id:references:in-reply-to:to:cc; bh=Lq39RP77AGx79p/R4lwUeEqGvV0zLaTcEMTevTVFlkc=; b=Wz7Y1Q6zW5/u6IZW+ADeYz1oeZraTzZtGGH/UUwlSI2Y6RUmpXLDLHnv flO26Unp/f4NMpi9aoOW8hYQCLFKb7scapWVgtWyh/b5Na+H3FPm1DF0e jPVCE2awROVx47+3u0jQC0dxUYIL4EaWJWzezkYuMqiYpNaFm6ZeYA2sy Fltsd+aMLT9CzV+UgR63cyvPv1iJBMSZ8kAC7Vvv2dI/FIBiZwHp3NW+U 5fZNfCs+a29OVcv0g06H68nF2xf0PUk3TWvQpedAnm47b0ik1G6hmFXt5 Xb0fs5+ZKxoqPlJGNab82ditywbcFXbQWbPVaWZ+vkNZkwz29k102Kzpf A==; X-IronPort-AV: E=McAfee;i="6600,9927,10865"; a="384580766" X-IronPort-AV: E=Sophos;i="6.03,231,1694761200"; d="scan'208";a="384580766" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Oct 2023 22:45:07 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10865"; a="879694028" X-IronPort-AV: E=Sophos;i="6.03,231,1694761200"; d="scan'208";a="879694028" Received: from mjwirth-mobl.amr.corp.intel.com (HELO [192.168.1.200]) ([10.209.151.162]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Oct 2023 22:45:03 -0700 From: Vishal Verma Date: Mon, 16 Oct 2023 23:44:56 -0600 Subject: [PATCH v6 2/3] mm/memory_hotplug: split memmap_on_memory requests across memblocks Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20231016-vv-kmem_memmap-v6-2-078f0d3c0371@intel.com> References: <20231016-vv-kmem_memmap-v6-0-078f0d3c0371@intel.com> In-Reply-To: <20231016-vv-kmem_memmap-v6-0-078f0d3c0371@intel.com> To: Andrew Morton , David Hildenbrand , Oscar Salvador , Dan Williams , Dave Jiang Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, Huang Ying , Dave Hansen , "Aneesh Kumar K.V" , Michal Hocko , Jonathan Cameron , Jeff Moyer , Vishal Verma X-Mailer: b4 0.12.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=9952; i=vishal.l.verma@intel.com; h=from:subject:message-id; bh=Lq39RP77AGx79p/R4lwUeEqGvV0zLaTcEMTevTVFlkc=; b=owGbwMvMwCXGf25diOft7jLG02pJDKl68jFqF6OYWHfL2patP9zwmjXKN3l1vZSNN8f1DX/85 5ke2r+1o5SFQYyLQVZMkeXvno+Mx+S25/MEJjjCzGFlAhnCwMUpABPJUmP4K9m0/j+T8YVPvx6o 3Xrq5PXw2RLm51K+3Vt3rXvI0HfmpSlQRaXxla1ltxb+USp/ynjofJbxrCX8J+NPXXPXXrdILsi ACQA= X-Developer-Key: i=vishal.l.verma@intel.com; a=openpgp; fpr=F8682BE134C67A12332A2ED07AFA61BEA3B84DFF The MHP_MEMMAP_ON_MEMORY flag for hotplugged memory is restricted to 'memblock_size' chunks of memory being added. Adding a larger span of memory precludes memmap_on_memory semantics. For users of hotplug such as kmem, large amounts of memory might get added from the CXL subsystem. In some cases, this amount may exceed the available 'main memory' to store the memmap for the memory being added. In this case, it is useful to have a way to place the memmap on the memory being added, even if it means splitting the addition into memblock-sized chunks. Change add_memory_resource() to loop over memblock-sized chunks of memory if caller requested memmap_on_memory, and if other conditions for it are met. Teach try_remove_memory() to also expect that a memory range being removed might have been split up into memblock sized chunks, and to loop through those as needed. This does preclude being able to use PUD mappings in the direct map; a proposal to how this could be optimized in the future is laid out here[1]. [1]: https://lore.kernel.org/linux-mm/b6753402-2de9-25b2-36e9-eacd49752b19@redhat.com/ Cc: Andrew Morton Cc: David Hildenbrand Cc: Michal Hocko Cc: Oscar Salvador Cc: Dan Williams Cc: Dave Jiang Cc: Dave Hansen Cc: Huang Ying Suggested-by: David Hildenbrand Reviewed-by: Dan Williams Signed-off-by: Vishal Verma --- mm/memory_hotplug.c | 214 ++++++++++++++++++++++++++++++++++++---------------- 1 file changed, 148 insertions(+), 66 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 6be7de9efa55..83e5ec377aad 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1380,6 +1380,43 @@ static bool mhp_supports_memmap_on_memory(unsigned long size) return arch_supports_memmap_on_memory(vmemmap_size); } +static int add_memory_create_devices(int nid, struct memory_group *group, + u64 start, u64 size, mhp_t mhp_flags) +{ + struct mhp_params params = { .pgprot = pgprot_mhp(PAGE_KERNEL) }; + struct vmem_altmap mhp_altmap = { + .base_pfn = PHYS_PFN(start), + .end_pfn = PHYS_PFN(start + size - 1), + }; + int ret; + + if ((mhp_flags & MHP_MEMMAP_ON_MEMORY)) { + mhp_altmap.free = memory_block_memmap_on_memory_pages(); + params.altmap = kmemdup(&mhp_altmap, sizeof(struct vmem_altmap), + GFP_KERNEL); + if (!params.altmap) + return -ENOMEM; + } + + /* call arch's memory hotadd */ + ret = arch_add_memory(nid, start, size, ¶ms); + if (ret < 0) + goto error; + + /* create memory block devices after memory was added */ + ret = create_memory_block_devices(start, size, params.altmap, group); + if (ret) + goto err_bdev; + + return 0; + +err_bdev: + arch_remove_memory(start, size, NULL); +error: + kfree(params.altmap); + return ret; +} + /* * NOTE: The caller must call lock_device_hotplug() to serialize hotplug * and online/offline operations (triggered e.g. by sysfs). @@ -1388,14 +1425,10 @@ static bool mhp_supports_memmap_on_memory(unsigned long size) */ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags) { - struct mhp_params params = { .pgprot = pgprot_mhp(PAGE_KERNEL) }; + unsigned long memblock_size = memory_block_size_bytes(); enum memblock_flags memblock_flags = MEMBLOCK_NONE; - struct vmem_altmap mhp_altmap = { - .base_pfn = PHYS_PFN(res->start), - .end_pfn = PHYS_PFN(res->end), - }; struct memory_group *group = NULL; - u64 start, size; + u64 start, size, cur_start; bool new_node = false; int ret; @@ -1436,28 +1469,21 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags) /* * Self hosted memmap array */ - if (mhp_flags & MHP_MEMMAP_ON_MEMORY) { - if (mhp_supports_memmap_on_memory(size)) { - mhp_altmap.free = memory_block_memmap_on_memory_pages(); - params.altmap = kmemdup(&mhp_altmap, - sizeof(struct vmem_altmap), - GFP_KERNEL); - if (!params.altmap) + if ((mhp_flags & MHP_MEMMAP_ON_MEMORY) && + mhp_supports_memmap_on_memory(memblock_size)) { + for (cur_start = start; cur_start < start + size; + cur_start += memblock_size) { + ret = add_memory_create_devices(nid, group, cur_start, + memblock_size, + mhp_flags); + if (ret) goto error; } - /* fallback to not using altmap */ - } - - /* call arch's memory hotadd */ - ret = arch_add_memory(nid, start, size, ¶ms); - if (ret < 0) - goto error_free; - - /* create memory block devices after memory was added */ - ret = create_memory_block_devices(start, size, params.altmap, group); - if (ret) { - arch_remove_memory(start, size, NULL); - goto error_free; + } else { + ret = add_memory_create_devices(nid, group, start, size, + mhp_flags); + if (ret) + goto error; } if (new_node) { @@ -1494,8 +1520,6 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags) walk_memory_blocks(start, size, NULL, online_memory_block); return ret; -error_free: - kfree(params.altmap); error: if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK)) memblock_remove(start, size); @@ -2076,6 +2100,23 @@ static int test_has_altmap_cb(struct memory_block *mem, void *arg) return 0; } +struct memory_range_altmap_info { + u64 num_memblocks; + u64 num_altmaps; +}; + +static int count_memory_range_altmaps_cb(struct memory_block *mem, void *arg) +{ + struct memory_range_altmap_info *altmap_info = + (struct memory_range_altmap_info *)arg; + + altmap_info->num_memblocks += 1; + if (mem->altmap) + altmap_info->num_altmaps += 1; + + return 0; +} + static int check_cpu_on_node(int nid) { int cpu; @@ -2146,11 +2187,75 @@ void try_offline_node(int nid) } EXPORT_SYMBOL(try_offline_node); -static int __ref try_remove_memory(u64 start, u64 size) +static void __ref remove_memory_blocks_and_altmaps(u64 start, u64 size) { - struct memory_block *mem; - int rc = 0, nid = NUMA_NO_NODE; + unsigned long memblock_size = memory_block_size_bytes(); struct vmem_altmap *altmap = NULL; + struct memory_block *mem; + u64 cur_start; + int rc; + + /* + * For memmap_on_memory, the altmaps could have been added on + * a per-memblock basis. Loop through the entire range if so, + * and remove each memblock and its altmap. + */ + for (cur_start = start; cur_start < start + size; + cur_start += memblock_size) { + rc = walk_memory_blocks(cur_start, memblock_size, &mem, + test_has_altmap_cb); + if (rc) { + altmap = mem->altmap; + /* + * Mark altmap NULL so that we can add a debug + * check on memblock free. + */ + mem->altmap = NULL; + } + + /* + * Memory block device removal under the device_hotplug_lock is + * a barrier against racing online attempts. + */ + remove_memory_block_devices(cur_start, memblock_size); + + arch_remove_memory(cur_start, memblock_size, altmap); + + /* Verify that all vmemmap pages have actually been freed. */ + if (altmap) { + WARN(altmap->alloc, "Altmap not fully unmapped"); + kfree(altmap); + } + } +} + +static int memblocks_have_altmaps(u64 start, u64 size) +{ + struct memory_range_altmap_info altmap_info = { + .num_memblocks = 0, + .num_altmaps = 0 + }; + + if (!mhp_memmap_on_memory()) + return 0; + + walk_memory_blocks(start, size, &altmap_info, + count_memory_range_altmaps_cb); + + if (!altmap_info.num_altmaps) + return 0; + + if (altmap_info.num_memblocks != altmap_info.num_altmaps) { + WARN_ONCE(1, "Not all memblocks in range have altmaps"); + return -EINVAL; + } + + return 1; +} + +static int __ref try_remove_memory(u64 start, u64 size) +{ + int rc, nid = NUMA_NO_NODE; BUG_ON(check_hotplug_memory_range(start, size)); @@ -2167,45 +2272,21 @@ static int __ref try_remove_memory(u64 start, u64 size) if (rc) return rc; - /* - * We only support removing memory added with MHP_MEMMAP_ON_MEMORY in - * the same granularity it was added - a single memory block. - */ - if (mhp_memmap_on_memory()) { - rc = walk_memory_blocks(start, size, &mem, test_has_altmap_cb); - if (rc) { - if (size != memory_block_size_bytes()) { - pr_warn("Refuse to remove %#llx - %#llx," - "wrong granularity\n", - start, start + size); - return -EINVAL; - } - altmap = mem->altmap; - /* - * Mark altmap NULL so that we can add a debug - * check on memblock free. - */ - mem->altmap = NULL; - } - } - /* remove memmap entry */ firmware_map_remove(start, start + size, "System RAM"); - /* - * Memory block device removal under the device_hotplug_lock is - * a barrier against racing online attempts. - */ - remove_memory_block_devices(start, size); - mem_hotplug_begin(); - arch_remove_memory(start, size, altmap); - - /* Verify that all vmemmap pages have actually been freed. */ - if (altmap) { - WARN(altmap->alloc, "Altmap not fully unmapped"); - kfree(altmap); + rc = memblocks_have_altmaps(start, size); + if (rc < 0) { + goto err; + } else if (rc == 0) { + /* no altmaps, do the removal directly */ + remove_memory_block_devices(start, size); + arch_remove_memory(start, size, NULL); + } else { + /* all memblocks in the range have altmaps */ + remove_memory_blocks_and_altmaps(start, size); } if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK)) { @@ -2218,8 +2299,9 @@ static int __ref try_remove_memory(u64 start, u64 size) if (nid != NUMA_NO_NODE) try_offline_node(nid); +err: mem_hotplug_done(); - return 0; + return (rc < 0 ? rc : 0); } /** From patchwork Tue Oct 17 05:44:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Verma, Vishal L" X-Patchwork-Id: 13424463 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.120]) (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 A733BC2C4 for ; Tue, 17 Oct 2023 05:45:10 +0000 (UTC) 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="jdqbW4xS" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1697521510; x=1729057510; h=from:date:subject:mime-version:content-transfer-encoding: message-id:references:in-reply-to:to:cc; bh=mEPqGi0w6uK1G2oMRp9GXgOlOlinp7OhMTBnsnQmtwo=; b=jdqbW4xSYtGm3in6LNaOGH//LK/46X1mvX3ir9FOqvQSHerBA4Q3Cwlz TrB7WjX1n2AxBzqVYHnfUP9zqMTiSn/U+0m+PXB6tPvuFw3YpJpCa2Nq8 fOb6nNchzj4F4m8LBTPbnnRKdZ8mgg4l+gaLZw+Tbcs1jCfGh8KzUIP5x h8GfdBeUbUKu+3IaGqwyMNA71G1XX/2y0e2UlHVNuIWJ1481ImnMCxZ2t 2ZIBCrCh8C6VVxIRRuyhxjaR59LAJlpYrMtrrcYn5foBAA1y1Qs9cVLH0 /lNBkCVeWRJBJS5VjklDz8LadyIFnjXUD72Z9nXuqnWDJX7AOOvC7lAIF w==; X-IronPort-AV: E=McAfee;i="6600,9927,10865"; a="384580776" X-IronPort-AV: E=Sophos;i="6.03,231,1694761200"; d="scan'208";a="384580776" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Oct 2023 22:45:07 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10865"; a="879694030" X-IronPort-AV: E=Sophos;i="6.03,231,1694761200"; d="scan'208";a="879694030" Received: from mjwirth-mobl.amr.corp.intel.com (HELO [192.168.1.200]) ([10.209.151.162]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Oct 2023 22:45:04 -0700 From: Vishal Verma Date: Mon, 16 Oct 2023 23:44:57 -0600 Subject: [PATCH v6 3/3] dax/kmem: allow kmem to add memory with memmap_on_memory Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20231016-vv-kmem_memmap-v6-3-078f0d3c0371@intel.com> References: <20231016-vv-kmem_memmap-v6-0-078f0d3c0371@intel.com> In-Reply-To: <20231016-vv-kmem_memmap-v6-0-078f0d3c0371@intel.com> To: Andrew Morton , David Hildenbrand , Oscar Salvador , Dan Williams , Dave Jiang Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, Huang Ying , Dave Hansen , "Aneesh Kumar K.V" , Michal Hocko , Jonathan Cameron , Jeff Moyer , Vishal Verma , Jonathan Cameron X-Mailer: b4 0.12.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=4972; i=vishal.l.verma@intel.com; h=from:subject:message-id; bh=mEPqGi0w6uK1G2oMRp9GXgOlOlinp7OhMTBnsnQmtwo=; b=owGbwMvMwCXGf25diOft7jLG02pJDKl68jEzt8d3qO3/2R3M0dv+gfv651PmOwQzOZilr5kzn l/89seZjlIWBjEuBlkxRZa/ez4yHpPbns8TmOAIM4eVCWQIAxenAEwkbgkjw7E7Lm+Z2b88qLgv Enox7OdGbbO9nLmXTvo+nsDxxX1WbCDD/7RVxdElk1n/SNmXxwW82D9HtfDNb3vGQlunA9vfr31 +mQcA X-Developer-Key: i=vishal.l.verma@intel.com; a=openpgp; fpr=F8682BE134C67A12332A2ED07AFA61BEA3B84DFF Large amounts of memory managed by the kmem driver may come in via CXL, and it is often desirable to have the memmap for this memory on the new memory itself. Enroll kmem-managed memory for memmap_on_memory semantics if the dax region originates via CXL. For non-CXL dax regions, retain the existing default behavior of hot adding without memmap_on_memory semantics. Cc: Andrew Morton Cc: David Hildenbrand Cc: Michal Hocko Cc: Oscar Salvador Cc: Dan Williams Cc: Dave Jiang Cc: Dave Hansen Cc: Huang Ying Reviewed-by: Jonathan Cameron Reviewed-by: David Hildenbrand Signed-off-by: Vishal Verma --- drivers/dax/bus.h | 1 + drivers/dax/dax-private.h | 1 + drivers/dax/bus.c | 3 +++ drivers/dax/cxl.c | 1 + drivers/dax/hmem/hmem.c | 1 + drivers/dax/kmem.c | 8 +++++++- drivers/dax/pmem.c | 1 + 7 files changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h index 1ccd23360124..cbbf64443098 100644 --- a/drivers/dax/bus.h +++ b/drivers/dax/bus.h @@ -23,6 +23,7 @@ struct dev_dax_data { struct dev_pagemap *pgmap; resource_size_t size; int id; + bool memmap_on_memory; }; struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data); diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index 27cf2daaaa79..446617b73aea 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -70,6 +70,7 @@ struct dev_dax { struct ida ida; struct device dev; struct dev_pagemap *pgmap; + bool memmap_on_memory; int nr_range; struct dev_dax_range { unsigned long pgoff; diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 0ee96e6fc426..ad9f821b8c78 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -367,6 +367,7 @@ static ssize_t create_store(struct device *dev, struct device_attribute *attr, .dax_region = dax_region, .size = 0, .id = -1, + .memmap_on_memory = false, }; struct dev_dax *dev_dax = devm_create_dev_dax(&data); @@ -1400,6 +1401,8 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) dev_dax->align = dax_region->align; ida_init(&dev_dax->ida); + dev_dax->memmap_on_memory = data->memmap_on_memory; + inode = dax_inode(dax_dev); dev->devt = inode->i_rdev; dev->bus = &dax_bus_type; diff --git a/drivers/dax/cxl.c b/drivers/dax/cxl.c index 8bc9d04034d6..c696837ab23c 100644 --- a/drivers/dax/cxl.c +++ b/drivers/dax/cxl.c @@ -26,6 +26,7 @@ static int cxl_dax_region_probe(struct device *dev) .dax_region = dax_region, .id = -1, .size = range_len(&cxlr_dax->hpa_range), + .memmap_on_memory = true, }; return PTR_ERR_OR_ZERO(devm_create_dev_dax(&data)); diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c index 5d2ddef0f8f5..b9da69f92697 100644 --- a/drivers/dax/hmem/hmem.c +++ b/drivers/dax/hmem/hmem.c @@ -36,6 +36,7 @@ static int dax_hmem_probe(struct platform_device *pdev) .dax_region = dax_region, .id = -1, .size = region_idle ? 0 : range_len(&mri->range), + .memmap_on_memory = false, }; return PTR_ERR_OR_ZERO(devm_create_dev_dax(&data)); diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c index c57acb73e3db..0aa6c45a4e5a 100644 --- a/drivers/dax/kmem.c +++ b/drivers/dax/kmem.c @@ -12,6 +12,7 @@ #include #include #include +#include #include "dax-private.h" #include "bus.h" @@ -56,6 +57,7 @@ static int dev_dax_kmem_probe(struct dev_dax *dev_dax) unsigned long total_len = 0; struct dax_kmem_data *data; int i, rc, mapped = 0; + mhp_t mhp_flags; int numa_node; /* @@ -136,12 +138,16 @@ static int dev_dax_kmem_probe(struct dev_dax *dev_dax) */ res->flags = IORESOURCE_SYSTEM_RAM; + mhp_flags = MHP_NID_IS_MGID; + if (dev_dax->memmap_on_memory) + mhp_flags |= MHP_MEMMAP_ON_MEMORY; + /* * Ensure that future kexec'd kernels will not treat * this as RAM automatically. */ rc = add_memory_driver_managed(data->mgid, range.start, - range_len(&range), kmem_name, MHP_NID_IS_MGID); + range_len(&range), kmem_name, mhp_flags); if (rc) { dev_warn(dev, "mapping%d: %#llx-%#llx memory add failed\n", diff --git a/drivers/dax/pmem.c b/drivers/dax/pmem.c index ae0cb113a5d3..f3c6c67b8412 100644 --- a/drivers/dax/pmem.c +++ b/drivers/dax/pmem.c @@ -63,6 +63,7 @@ static struct dev_dax *__dax_pmem_probe(struct device *dev) .id = id, .pgmap = &pgmap, .size = range_len(&range), + .memmap_on_memory = false, }; return devm_create_dev_dax(&data);