From 39aec97630e63559af2b84832da91e074582445d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20=C4=8Cerm=C3=A1k?= <sairon@sairon.cz>
Date: Fri, 14 Feb 2025 12:21:38 +0100
Subject: [PATCH] fs/erofs: add config options for dedupe, fragments and
 ztailpacking
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Add Kconfig toggles for a few more extended options that are useful for
reducing size and improving performance of EROFS images. Descriptions of the
config options were taken from the erofs-utils manpage.

Signed-off-by: Jan Čermák <sairon@sairon.cz>
[Arnout: fix Config.in help text and indentation]
Signed-off-by: Arnout Vandecappelle <arnout@mind.be>
---
 fs/erofs/Config.in | 27 +++++++++++++++++++++++++++
 fs/erofs/erofs.mk  | 16 ++++++++++++++++
 2 files changed, 43 insertions(+)

diff --git a/fs/erofs/Config.in b/fs/erofs/Config.in
index 2041a0034e..91f51b76d7 100644
--- a/fs/erofs/Config.in
+++ b/fs/erofs/Config.in
@@ -58,6 +58,33 @@ config BR2_TARGET_ROOTFS_EROFS_LZMA_LEVEL
 
 endif # BR2_TARGET_ROOTFS_EROFS_LZMA
 
+config BR2_TARGET_ROOTFS_EROFS_DEDUPE
+	bool "enable data deduplication"
+	depends on !BR2_TARGET_ROOTFS_EROFS_NONE
+	help
+	  Enable global compressed data deduplication to reduce FS image
+	  size. Introduced in Linux 6.1.
+
+config BR2_TARGET_ROOTFS_EROFS_FRAGMENTS
+	bool "enable fragments packing"
+	help
+	  Pack the tail part (pcluster) of compressed files, or entire
+	  files, into a special inode for smaller image size.
+	  Introduced in Linux 6.1.
+
+config BR2_TARGET_ROOTFS_EROFS_ALL_FRAGMENTS
+	bool "enable fragments packing"
+	help
+	  Forcely record the whole files into a special inode for better
+	  compression. Introduced in Linux 6.1.
+
+config BR2_TARGET_ROOTFS_EROFS_ZTAILPACKING
+	bool "enable ztailpacking"
+	help
+	  Pack the tail part (pcluster) of compressed files into its
+	  metadata to save more space and the tail part I/O. Introduced
+	  in Linux 5.17.
+
 config BR2_TARGET_ROOTFS_EROFS_PCLUSTERSIZE
 	int "pcluster size"
 	default 0
diff --git a/fs/erofs/erofs.mk b/fs/erofs/erofs.mk
index e8d30bace8..3b64cb1c6e 100644
--- a/fs/erofs/erofs.mk
+++ b/fs/erofs/erofs.mk
@@ -22,6 +22,22 @@ ifneq ($(BR2_TARGET_ROOTFS_EROFS_PCLUSTERSIZE),0)
 ROOTFS_EROFS_ARGS += -C$(strip $(BR2_TARGET_ROOTFS_EROFS_PCLUSTERSIZE))
 endif
 
+ifeq ($(BR2_TARGET_ROOTFS_EROFS_DEDUPE),y)
+ROOTFS_EROFS_ARGS += -Ededupe
+endif
+
+ifeq ($(BR2_TARGET_ROOTFS_EROFS_FRAGMENTS),y)
+ROOTFS_EROFS_ARGS += -Efragments
+endif
+
+ifeq ($(BR2_TARGET_ROOTFS_EROFS_ALL_FRAGMENTS),y)
+ROOTFS_EROFS_ARGS += -Eall-fragments
+endif
+
+ifeq ($(BR2_TARGET_ROOTFS_EROFS_ZTAILPACKING),y)
+ROOTFS_EROFS_ARGS += -Eztailpacking
+endif
+
 define ROOTFS_EROFS_CMD
 	$(HOST_DIR)/bin/mkfs.erofs $(ROOTFS_EROFS_ARGS) $@ $(TARGET_DIR)
 endef