From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from DM5PR21CU001.outbound.protection.outlook.com (mail-centralusazon11011011.outbound.protection.outlook.com [52.101.62.11]) (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 55AD13242B8; Mon, 14 Sep 2026 02:24:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.62.11 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789352685; cv=fail; b=pMy7n3ipYuF1JfoGxOOfpwHwFJ/QlWzWmauFOV8CZPoD/iqaXztBzyFJJ83LG1O5NJMVXhAv6jlUBWuEPTsUVTDNfDBPXoD+tVgPZgBmnXM1n4LE0XxkqYKMwaOihV7rUEU5EzKzaKWxUYIP06r/vJ+TmYQfKSiaQ7L8gdb9LBQ= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789352685; c=relaxed/simple; bh=kD3cEqxI/VPgz7aIqtpKmXEcSDY1J8m5719wxmgu7jM=; h=From:Date:Subject:Content-Type:Message-Id:References:In-Reply-To: To:Cc:MIME-Version; b=MtVkHhXLffwz9sXnru8DdawqoTirsZsmqRJW7Oa+9Lq+JJwRh2uzq0f8Bii79BQFwGxU38B+fxTgxhClA+M6WGlbmsAsJwO/rq81UXs/ARGA/Ysn6UTC+3sN7Wq8g4gYGhS28mS/wWDdzF0Hh21HGZsq/WBN/O9911DXgU/vQh4= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b=RgvAuRWW; arc=fail smtp.client-ip=52.101.62.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nvidia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b="RgvAuRWW" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=Y4kNAGv4P3i+CApyTQFH7HQYZ/0S5yKKDL7+7LHgyTc2ImMHs+hXb/DdRacxnfUzr6+3SvPCDAjStWCD1IxO5GSgUr6guKG0PWScrt6AwuiVhQUx32E3bs6GY38G2W2vUUH0I6DmbKw8j8KdMaNG4eUrBneusFlj/uPLvBK73RHE2xe+lPk8DJhGAlcRRMuznerXY/ceq5ukJqd334rlMVZF3ZC3l8PUe1AgECIbUGp/XqIDU4dJdUbHvGPG3lcI5F9xYA2A9tXreQYCl3UL39dTy2QeUVyRVRnimOLS1dIOQGkWTqxRNwdXuwQodLf9nTWepKE45havsTQNlSNgPw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=xVv9wxA/M8gednBaRD1HGziV0QOHZmyR40hMEBPFV00=; b=NGaWiExv13SDw2gFL80ipk6P7zhnllXvouDvJnK5nZ9b6ThRITZIamFPdTssIuwV9jvZMrnzDWWgHjLgCI8v75MVenI3RbMA+KoVsxF1b/aifaGTR8dOBMA2aHF6s4K0/e0LutIK7bjmnY7jtnfYqaPrZJQjSNqVszStZcJRvhihe4O1L13fVDk7O/jH8DYudqaYPApebxKI/N6Z6Vsr5DA0QBZWjpypOf4XePRbKlL6y/GOsq3vFrPFmg2jECmwf5hFIA6mnhVgTz5vVOrBRt1tQjAmMi69zo68Z7rv8QgMA2xN3yhIo9Swk/GLOluFf1tQdWKAmP+EkPj1TCd+6g== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=xVv9wxA/M8gednBaRD1HGziV0QOHZmyR40hMEBPFV00=; b=RgvAuRWWtK+Iul9CpKWeIbk4iCO/+jzOcVeVD35wiMJC6x4aqkDtDG2CqtJvmIqVG+zpby6vdVLpL2yJH7Xt4Il9/jC1Odp1h4BCEh4BK0eA5yyQ0J8+nF9nZBssYF3qDY6DcqdYmutwrJvCViXhPFGo8s7ubErvs2WZfMgZj2yl383Bo99twu1vhcWoaUMqiYCj7Hp5rNSIA22pH7H3/4/lh23w0insMwD8NtfaP98O56054X0W7SsZ2iniDBxMScEUwW9JOFBEg/nVYSUF63sqhD161N8tYIir3/eKqUzUuUstQKYL2QxcizTdaCMV5eV7yVnW0caR7e5FRfIGwg== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from IA0PR12MB8374.namprd12.prod.outlook.com (2603:10b6:208:40e::7) by DS0PR12MB6486.namprd12.prod.outlook.com (2603:10b6:8:c5::21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.406.12; Mon, 14 Sep 2026 02:24:21 +0000 Received: from IA0PR12MB8374.namprd12.prod.outlook.com ([fe80::d85f:4c87:ae84:3f16]) by IA0PR12MB8374.namprd12.prod.outlook.com ([fe80::d85f:4c87:ae84:3f16%5]) with mapi id 15.21.0406.007; Mon, 14 Sep 2026 02:24:21 +0000 From: Zi Yan Date: Sun, 13 Sep 2026 22:24:06 -0400 Subject: [PATCH v4 08/16] erofs: mm/pagemap: add readahead_folio_last() to avoid folio->private Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260913-remove-pg_private-v4-8-848550f7574e@nvidia.com> References: <20260913-remove-pg_private-v4-0-848550f7574e@nvidia.com> In-Reply-To: <20260913-remove-pg_private-v4-0-848550f7574e@nvidia.com> To: David Hildenbrand , "Matthew Wilcox (Oracle)" , Andrew Morton , Muchun Song , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Gregory Price , Ying Huang , Alistair Popple , Johannes Weiner , Qi Zheng , Shakeel Butt , Kairui Song Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Zi Yan , Gao Xiang , Chao Yu , Jan Kara , Yue Hu , Jeffle Xu , Sandeep Dhavale , Hongbo Li , Chunhai Guo , linux-erofs@lists.ozlabs.org, linux-fsdevel@vger.kernel.org X-Mailer: b4 0.16.0 X-ClientProxiedBy: BLAP220CA0017.NAMP220.PROD.OUTLOOK.COM (2603:10b6:208:32c::22) To IA0PR12MB8374.namprd12.prod.outlook.com (2603:10b6:208:40e::7) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: IA0PR12MB8374:EE_|DS0PR12MB6486:EE_ X-MS-Office365-Filtering-Correlation-Id: 3b0577a3-d1f6-4fec-74dd-08df1207493d X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|23010399003|7416014|366016|376014|1800799024|22082099003|18002099003|921020|10067099003|56012099006|11063799006; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:IA0PR12MB8374.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(23010399003)(7416014)(366016)(376014)(1800799024)(22082099003)(18002099003)(921020)(10067099003)(56012099006)(11063799006);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?Q3AvWVV3bU1kVDZXQUFtRHR6YzBodEw3WkRpb011M3hySk0wNVFpZXpGdllS?= =?utf-8?B?eXNTbHkyRUdja0hDVGJFMmpQMFBiNWxmdU92b1g4aDA1VGZxRXE3ejlhSy9C?= =?utf-8?B?R3JxNHJJbzZNdHVUK2FnVURpUjhvZUZjcklhcUFPYXQ1ZCtRTlpDdGNna29y?= =?utf-8?B?em9zbkZKbTd0eWpHZjZMR1UvVjgreS9HeUJQbEFsQUFsK0ZjWGpCWU13UnBa?= =?utf-8?B?ci9sdVVVdzBhSHViUkZkaWEzdUJ0dVdZWEVaM3NBZUVDMjN6SWhlekVFMmpI?= =?utf-8?B?VVlJSy9GNmptdGRJRUNRYjZuUW9ZKzBBZVRONzFYUFIxaEU3dGxCZU1TT29s?= =?utf-8?B?eU1kSkl2SEpCc0dNVDh2WndwK1JwYmNpUU9jVkkwanVjL3hyR3QvUE12QzJv?= =?utf-8?B?Uk9zdjExaTJFWVo1TlFlbzlqL0JIajQyRWU2V0EzejBCZWZtQ2J0bEFVWVJq?= =?utf-8?B?MnR0cWxuYVphOG4wUmNLMzNNaXBWeEszZ0NnSXFXcUNhUFByVkp0eGdxclhH?= =?utf-8?B?SzBTUHNDdmIwaEd5ZmllMzBiYVdxdjlFNG5TUnpyYUE1Y1lQdlhlbWtqeVFU?= =?utf-8?B?UUFvWWQxN1VFNW9hOVF0S3dqZ3J4SGZuUlNQVUlYbVFVS1JMWm4zeVF1NGRI?= =?utf-8?B?dms1VVFGd3pGekdROGd5dS9lU1pJS0Qrek84clhNZFZzVUNRbmR6Ulg1Nnh5?= =?utf-8?B?ZHJWZUMzY2lHZ2xMSzVIRFgwMksxODVZLzlCaGZWWW1xejRlb3VDbTNYbTJY?= =?utf-8?B?WU5rVlQxZU9nZEVZSjB6NXNIbmxmSUYrV2pXOC9KbEsxVXh2UDg2MmZROHJY?= =?utf-8?B?bjIySlR5Tk5UNVFXcU9qQmRBME9nZCtMQVJGVVNUYmdhNVJ2MWFmSERLM3dM?= =?utf-8?B?akEvME1vTU5laUZIWXVPWFljYmZCTG53cTVEMHZ4SFdtQWFuOTJCaldsZlR2?= =?utf-8?B?V2FhclpzVDcrVkhYeXFMMmV0WGZTaHJTZjcwU0xId2xIbnppNFp3SU9PLzk2?= =?utf-8?B?K1p2TkxmbEFSOVg3L0ZlOElNYW45cXVXZUp6ZU8zcmE0dWlPUUtyTlU3ZVRF?= =?utf-8?B?eklzRlFBa3dHQzFWNUQ4ZkVRKzh0L2U5Tno1VkJmU2NrT3dBejFHNm55clIv?= =?utf-8?B?L25ZYmJsSlZ1OVU3UjV4dFgvM1l5VkNDcnJxUjNUc2VCSFFVVGFTSzZnNjBp?= =?utf-8?B?RnBtQVRBTFl4R3l2Q0VEczRQR2M0ckdMakx4UjFmVHNRUXJZTStQUjBZSSs3?= =?utf-8?B?UkVxKy80N1NJR2R0cWNSZmczWUg1NUsvbE9zc0U3ZGRSVFpYUUVpTzRXb2x1?= =?utf-8?B?NmZvanl3U3pjZHRIYS9DcEZsTXN2TXhEV3NHSGhtbEN2NHY4Y0kvWnIzK09a?= =?utf-8?B?SWxGTEFVc2xKazI3TjdnLzBDazEyODdTK2VIM3VjZFNLbXVUN2crY2l5bURS?= =?utf-8?B?emdzakhWZUdvMGthTUF2NkVsVC9LUTltSjA1a280ZFJIMnBxKzlhWDZXT3RX?= =?utf-8?B?VElBUEgwUFg4RVN3SHJFVnFkbE4yOTkwbXhpSEFnUnZiOVRqclB6MFR1Ylh6?= =?utf-8?B?SzNSZjhYTUcwMUdoUFBZc28vblZtaEpSZ2VjRU1yanljRG9pWTFsQnd6Zjgr?= =?utf-8?B?d2RhbFJNUW1vRHIxZFQzTzFmNDJxUzY5QUl0b1g0eUF6QWc3d0RVcUpLZlNV?= =?utf-8?B?TXFCMXUzZG1RUGV1dHdBSzI1NHhybzJYODYvaWZwUnpwTExyRUhkZFZBRHUr?= =?utf-8?B?TzlTb2cycmMzbndHWENVbzdPeXozcTdoZ09WVzYzVkVBWGJkUmtqbTRReXpT?= =?utf-8?B?N2ptY1cwc01DeGNyazUrTDd6Q1J6OHpnNW5hakZlOHBoSVQzWE9xcTYxS3pl?= =?utf-8?B?UzRjeUVveUw3RmhVSjRyM0JzOWFySHFoU2R6dmYyUGMwT1NOUElHOFV4a1dW?= =?utf-8?B?bXc5RXppbjFyaExhWjVTQ0Z2emVUc2Voa2xMN0lzVHR3L0dIOHBFY056Q2gv?= =?utf-8?B?d1h3VlJvZXAxQVUrNXVIeWloV3NET0NyUlFhbGZ5OHdRVmNJUU5RSS9MTnRV?= =?utf-8?B?aWlFcGl6OEhmM3pPTldtdWw3TVlCUlpFRTlDYlpZUHJHekM4ZE0xenpHMm03?= =?utf-8?B?amJGMUp0ZjhBRnNLUXNQSVZBN3B3TGZYQnVybDFQNXBUODV2S1MwM3RFZXl3?= =?utf-8?B?NkowbVVQSkc3RUdPcmUrem43TkRJVDNUK2czakl3M1djNkg5ajRPSm1mRGdq?= =?utf-8?B?TzJXSUVMNHE3YlM3RVFIVjQ5VE1rVGhNZjI2QXlpYXVkZXFzRHlnM2xmeVda?= =?utf-8?Q?5yMth6Dn8KZg4D5Oj0?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3b0577a3-d1f6-4fec-74dd-08df1207493d X-MS-Exchange-CrossTenant-AuthSource: IA0PR12MB8374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Sep 2026 02:24:21.3702 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: tLclKViQFBsmsz6LxOhuc56yLjJcbwjEednZGh54FN2MeVoXdjx9VioF0SS84/WJ X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB6486 erofs needs to traverse readahead folios in reverse order to achieve maximum performance by 1. reading all folios from readahead_folio(); 2. storing the prior folio pointer in folio->private; 3. traverse from the last folio to the first one. Add readahead_folio_last() to achieve the same function without using folio->private. __readahead_advance() helper shares readahead_control adjustment code among __readahead_folio(), readahead_folio_last(), and __readahead_batch() by checking new private member, _forward, of readahead_control. It prepares for a future commit that replaces PG_private checks with !folio->private checks. After switching the checks, erofs's use of folio->private without bumping folio refcount can cause unexpected outcomes, e.g., in filemap_release_folio(), try_to_free_buffers() becomes reachable. No functional change intended. Assisted-by: LLM To: Gao Xiang To: Chao Yu To: "Matthew Wilcox (Oracle)" To: Jan Kara Cc: Yue Hu Cc: Jeffle Xu Cc: Sandeep Dhavale Cc: Hongbo Li Cc: Chunhai Guo Cc: linux-erofs@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Cc: linux-mm@kvack.org Acked-by: David Hildenbrand (Arm) Signed-off-by: Zi Yan --- fs/erofs/zdata.c | 13 +++-------- include/linux/pagemap.h | 60 ++++++++++++++++++++++++++++++++++++++++++------- 2 files changed, 55 insertions(+), 18 deletions(-) diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c index e1e25ca0d1904..78fd7d980e957 100644 --- a/fs/erofs/zdata.c +++ b/fs/erofs/zdata.c @@ -1898,21 +1898,14 @@ static void z_erofs_readahead(struct readahead_control *rac) struct inode *realinode = erofs_real_inode(sharedinode, &need_iput); Z_EROFS_DEFINE_FRONTEND(f, realinode, sharedinode, readahead_pos(rac)); unsigned int nrpages = readahead_count(rac); - struct folio *head = NULL, *folio; + struct folio *folio; int err; trace_erofs_readahead(realinode, readahead_index(rac), nrpages, false); z_erofs_pcluster_readmore(&f, rac, true); - while ((folio = readahead_folio(rac))) { - folio->private = head; - head = folio; - } - - /* traverse in reverse order for best metadata I/O performance */ - while (head) { - folio = head; - head = folio_get_private(folio); + /* traverse from last to first for best metadata I/O performance */ + while ((folio = readahead_folio_last(rac))) { err = z_erofs_scan_folio(&f, folio, true); if (err && err != -EINTR) erofs_err(realinode->i_sb, "readahead error at folio %lu @ nid %llu", diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 939f3a5e973f6..1e3462357aaa4 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -1415,6 +1415,7 @@ struct readahead_control { bool dropbehind; bool _workingset; unsigned long _pflags; + bool _forward; }; #define DEFINE_READAHEAD(ractl, f, r, m, i) \ @@ -1479,18 +1480,29 @@ void page_cache_async_readahead(struct address_space *mapping, page_cache_async_ra(&ractl, folio, req_count); } +/* + * Adjust readahead_control to ensure next folio comes from + * [_index, _index + _nr_pages) afterwards and reset _batch_count. + */ +static inline void __readahead_advance(struct readahead_control *rac) +{ + if (rac->_forward) + rac->_index += rac->_batch_count; + + rac->_nr_pages -= rac->_batch_count; + rac->_batch_count = 0; +} + static inline struct folio *__readahead_folio(struct readahead_control *ractl) { struct folio *folio; BUG_ON(ractl->_batch_count > ractl->_nr_pages); - ractl->_nr_pages -= ractl->_batch_count; - ractl->_index += ractl->_batch_count; + __readahead_advance(ractl); + ractl->_forward = true; - if (!ractl->_nr_pages) { - ractl->_batch_count = 0; + if (!ractl->_nr_pages) return NULL; - } folio = xa_load(&ractl->mapping->i_pages, ractl->_index); VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); @@ -1516,6 +1528,39 @@ static inline struct folio *readahead_folio(struct readahead_control *ractl) return folio; } +/** + * readahead_folio_last - Get the next folio to read, from the tail. + * @ractl: The current readahead request. + * + * Like readahead_folio(), but walks the range back-to-front. The folio is + * returned locked with its refcount dropped; the caller unlocks it once I/O + * completes. Compound folios are returned once, at their head index. + * + * Context: The folio is locked. + * Return: A pointer to the next folio, or %NULL when done. + */ +static inline struct folio *readahead_folio_last(struct readahead_control *ractl) +{ + struct folio *folio; + + /* Drop the previously returned batch from the remaining range. */ + __readahead_advance(ractl); + ractl->_forward = false; + + if (!ractl->_nr_pages) + return NULL; + + /* xa_load() follows sibling entries, so a tail index returns the head */ + folio = xa_load(&ractl->mapping->i_pages, + ractl->_index + ractl->_nr_pages - 1); + VM_WARN_ON_ONCE_FOLIO(!folio_test_locked(folio), folio); + + ractl->_batch_count = folio_nr_pages(folio); + + folio_put(folio); + return folio; +} + static inline unsigned int __readahead_batch(struct readahead_control *rac, struct page **array, unsigned int array_sz) { @@ -1524,9 +1569,8 @@ static inline unsigned int __readahead_batch(struct readahead_control *rac, struct folio *folio; BUG_ON(rac->_batch_count > rac->_nr_pages); - rac->_nr_pages -= rac->_batch_count; - rac->_index += rac->_batch_count; - rac->_batch_count = 0; + __readahead_advance(rac); + rac->_forward = true; xas_set(&xas, rac->_index); rcu_read_lock(); -- 2.53.0