From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 98463560ACA for ; Tue, 8 Sep 2026 15:47:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788882459; cv=none; b=YO1HjssxuujYOh8MHYZ8FlnMIuE2s+ZSLFjbRdqZ2wxEgxiy+qPm8BSwpoNhCM7wVcWa5HPmliq85EJqCCXiW2g2gZ8QRa7+zZW8Fq60U70Zui81Z7l/zhfJSR9oZnEImgOqpD8KqAMQGnmE23q4wiXJ40pXPKh63Bvomt+oikc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788882459; c=relaxed/simple; bh=mIVxMsvlRgr2ybASwb0ZJsvLCCQ149vSt7HY5LnhUCs=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=IvIwzd1Oz1aWlgZdcVSq5Oi6YHuO0RobkQKBHBXBlzKvL7IUttxIBxB29nxEvsjWqAKj2dK3iHfFyTTclQtPX5cmIOXpIuHjdTLmz7fdOE4wC0LcnAOmRlvxyLe+MxE6R8HIEKoBtiFdWYw+GiCpj74ayZSzhN2a7B3DgrEjvxk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=c0jGeSCb; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="c0jGeSCb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C244E1F00A3A; Tue, 8 Sep 2026 15:47:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788882457; bh=Lwtouv1vIsPs6zrihx9rtxLSNo9w1Vw5QEheH4pUII4=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=c0jGeSCbxBKFMslsHx1VKdqJ+PlArCxziNPylyn0RCAGmq7Vayan+VGB5OFs366Pu +CLrPtenujgEZU26iBMkO0/LOQXTEjap0BrmsGGa3iwe/5wL/9PGZ9XqKY/8gIYsit OqIZDJpJAP19/bzdtpv5wpruX7LITG2ZX3QKrRc9tBtedlw9RCokpzB3TCos7KQq4V iaYQD/M5SfWtptQ5d/XJGD1/rv4XhrQ6ptOaHC7Mha30+7u8uqter7/flcHiPv18o6 cIwi8KNLy0SBxfE1mGwxuEiVGBsnYaAUwCntUbZJy/gjdQUelDwLFsCcmENrf5L7P5 7z6f9usqbYvvA== Message-ID: Date: Tue, 8 Sep 2026 17:47:25 +0200 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 v3 06/14] f2fs: stop using PG_private To: Zi Yan , "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, Jaegeuk Kim , Chao Yu , linux-f2fs-devel@lists.sourceforge.net References: <20260907-remove-pg_private-v3-0-6ae22f9d9272@nvidia.com> <20260907-remove-pg_private-v3-6-6ae22f9d9272@nvidia.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <20260907-remove-pg_private-v3-6-6ae22f9d9272@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/8/26 04:56, Zi Yan wrote: > f2fs sets its PAGE_PRIVATE_* flags in page->private and checking > page->private != NULL is equivalent to checking PG_private. Change > PagePrivate() to page_private(). Meanwhile, in set_page_private_##name(), > page->private is first set to 0/NULL before an PAGE_PRIVATE_* flag is set, > but it can cause confusion when PG_private is removed and > page->private != NULL is used instead. Change it to initialize > page->private to PAGE_PRIVATE_NOT_POINTER instead and retain the original > semantics. > > It prepares for a future commit that removes PG_private. > > No functional change intended. > > Assisted-by: Claude:claude-opus-4-8 > Assisted-by: Codex:gpt-5 > To: Jaegeuk Kim > To: Chao Yu > Cc: linux-f2fs-devel@lists.sourceforge.net > Cc: linux-kernel@vger.kernel.org > Acked-by: Usama Arif > Acked-by: Chao Yu > Signed-off-by: Zi Yan > --- > fs/f2fs/f2fs.h | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index 9940a6cecf1a2..2f7ab5888b078 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -2691,7 +2691,7 @@ static inline bool folio_test_f2fs_##name(const struct folio *folio) \ > } \ > static inline bool page_private_##name(struct page *page) \ > { \ > - return PagePrivate(page) && \ > + return page_private(page) && \ > test_bit(PAGE_PRIVATE_NOT_POINTER, &page_private(page)) && \ > test_bit(PAGE_PRIVATE_##flagname, &page_private(page)); \ > } > @@ -2710,9 +2710,9 @@ static inline void folio_set_f2fs_##name(struct folio *folio) \ > } \ > static inline void set_page_private_##name(struct page *page) \ > { \ > - if (!PagePrivate(page)) \ > - attach_page_private(page, (void *)0); \ > - set_bit(PAGE_PRIVATE_NOT_POINTER, &page_private(page)); \ > + if (!page_private(page)) \ > + attach_page_private(page, \ > + (void *)BIT(PAGE_PRIVATE_NOT_POINTER)); \ > set_bit(PAGE_PRIVATE_##flagname, &page_private(page)); \ > } Very weird interface. Why do we even need the page-based interface still? $ git grep -E "(set|clear)_page_private" compress.c: clear_page_private_gcing(cc->rpages[i]); compress.c: set_page_private_gcing(cc->rpages[i]); compress.c: clear_page_private_gcing(cic->rpages[i]); f2fs.h:static inline void set_page_private_##name(struct page *page) \ f2fs.h:static inline void clear_page_private_##name(struct page *page) \ Seeing code like: clear_page_private_gcing(cc->rpages[i]); if (folio_test_writeback(page_folio(cc->rpages[i]))) end_page_writeback(cc->rpages[i]); Makes me wonder whether we can just use the folio helper instead? In f2fs_iget(), we enable large folios only when !f2fs_compressed_file(inode). So naive me would assume that we can just get rid of the set_page_private_/clear_page_private_ stuff entirely. IOW something like: >From efcde918178604de11d16c6dc5485542ab4dcdaf Mon Sep 17 00:00:00 2001 From: "David Hildenbrand (Arm)" Date: Tue, 8 Sep 2026 17:46:06 +0200 Subject: [PATCH] tmp Signed-off-by: David Hildenbrand (Arm) --- fs/f2fs/compress.c | 29 ++++++++++++++++++----------- fs/f2fs/f2fs.h | 13 ------------- 2 files changed, 18 insertions(+), 24 deletions(-) diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c index ce88092d9ce26..0e9cc0fa297a4 100644 --- a/fs/f2fs/compress.c +++ b/fs/f2fs/compress.c @@ -1064,13 +1064,15 @@ static void cancel_cluster_writeback(struct compress_ctx *cc, /* Cancel writeback and stay locked. */ for (i = 0; i < cc->cluster_size; i++) { + struct folio *folio = page_folio(cc->rpages[i]); + if (i < submitted) { inode_inc_dirty_pages(cc->inode); - lock_page(cc->rpages[i]); + folio_lock(folio); } - clear_page_private_gcing(cc->rpages[i]); - if (folio_test_writeback(page_folio(cc->rpages[i]))) - end_page_writeback(cc->rpages[i]); + folio_clear_f2fs_gcing(folio); + if (folio_test_writeback(folio)) + folio_end_writeback(folio); } } @@ -1078,11 +1080,15 @@ static void set_cluster_dirty(struct compress_ctx *cc) { int i; - for (i = 0; i < cc->cluster_size; i++) - if (cc->rpages[i]) { - set_page_dirty(cc->rpages[i]); - set_page_private_gcing(cc->rpages[i]); - } + for (i = 0; i < cc->cluster_size; i++) { + struct folio *folio; + + if (!cc->rpages[i]) + continue; + folio = page_folio(cc->rpages[i]); + folio_mark_dirty(folio); + folio_set_f2fs_gcing(folio); + } } static int prepare_compress_overwrite(struct compress_ctx *cc, @@ -1477,8 +1483,9 @@ void f2fs_compress_write_end_io(struct bio *bio, struct folio *folio) for (i = 0; i < cic->nr_rpages; i++) { WARN_ON(!cic->rpages[i]); - clear_page_private_gcing(cic->rpages[i]); - end_page_writeback(cic->rpages[i]); + folio = page_folio(cic->rpages[i]); + folio_clear_f2fs_gcing(folio); + folio_end_writeback(folio); } page_array_free(sbi, cic->rpages, cic->nr_rpages); diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 9940a6cecf1a2..0cfba8742d4b4 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -2707,13 +2707,6 @@ static inline void folio_set_f2fs_##name(struct folio *folio) \ v |= (unsigned long)folio->private; \ folio->private = (void *)v; \ } \ -} \ -static inline void set_page_private_##name(struct page *page) \ -{ \ - if (!PagePrivate(page)) \ - attach_page_private(page, (void *)0); \ - set_bit(PAGE_PRIVATE_NOT_POINTER, &page_private(page)); \ - set_bit(PAGE_PRIVATE_##flagname, &page_private(page)); \ } #define PAGE_PRIVATE_CLEAR_FUNC(name, flagname) \ @@ -2726,12 +2719,6 @@ static inline void folio_clear_f2fs_##name(struct folio *folio) \ folio_detach_private(folio); \ else \ folio->private = (void *)v; \ -} \ -static inline void clear_page_private_##name(struct page *page) \ -{ \ - clear_bit(PAGE_PRIVATE_##flagname, &page_private(page)); \ - if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER)) \ - detach_page_private(page); \ } PAGE_PRIVATE_GET_FUNC(nonpointer, NOT_POINTER); -- 2.43.0 -- Cheers, David