linux-kernel - [PATCH v1 0/9] Enable exfat_get_block to support obtaining multiple clusters

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Message-ID: <20251226094440.455563-1-chizhiling@163.com>
Date: Fri, 26 Dec 2025 17:44:31 +0800
From: Chi Zhiling <chizhiling@....com>
To: linux-fsdevel@...r.kernel.org,
	linux-kernel@...r.kernel.org
Cc: Namjae Jeon <linkinjeon@...nel.org>,
	Sungjong Seo <sj1557.seo@...sung.com>,
	Yuezhang Mo <yuezhang.mo@...y.com>,
	Alexander Viro <viro@...iv.linux.org.uk>,
	Christian Brauner <brauner@...nel.org>,
	Jan Kara <jack@...e.cz>,
	Matthew Wilcox <willy@...radead.org>,
	Chi Zhiling <chizhiling@...inos.cn>
Subject: [PATCH v1 0/9] Enable exfat_get_block to support obtaining multiple clusters

From: Chi Zhiling <chizhiling@...inos.cn>

This patch series significantly improves exFAT read performance
by adding multi-cluster mapping support.
The changes reduce get_block calls during sequential reads,
particularly benefiting small cluster sizes.

- Extends exfat_get_cluster() and exfat_map_cluster() to handle multiple contiguous clusters
- Adds buffer head caching for FAT table reads

Performance results show ~10% improvement for 512-byte clusters (454->511 MB/s)
and reduced get_block overhead from 10.8% to 0.02% for NO_FAT_CHAIN files.

All criticism and suggestions are welcome :)

Chi Zhiling (9):
  exfat: add cache option for __exfat_ent_get
  exfat: support reuse buffer head for exfat_ent_get
  exfat: reuse cache to improve exfat_get_cluster
  exfat: improve exfat_count_num_clusters
  exfat: improve exfat_find_last_cluster
  exfat: remove unused parameters from exfat_get_cluster
  exfat: tweak exfat_cache_lookup to support zero offset cluster
  exfat: support multi-cluster for exfat_map_cluster
  exfat: support multi-cluster for exfat_get_cluster

 fs/exfat/cache.c    | 108 ++++++++++++++++++++++++++++----------------
 fs/exfat/exfat_fs.h |   7 ++-
 fs/exfat/fatent.c   |  61 ++++++++++++++++---------
 fs/exfat/inode.c    |  46 +++++++++++--------
 4 files changed, 137 insertions(+), 85 deletions(-)

-- 
2.43.0