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+# SPDX-License-Identifier: GPL-2.0-only
+
+config EROFS_FS
+	tristate "EROFS filesystem support"
+	depends on BLOCK
+	select CRC32
+	select CRYPTO if EROFS_FS_ZIP_ACCEL
+	select CRYPTO_DEFLATE if EROFS_FS_ZIP_ACCEL
+	select FS_IOMAP
+	select LZ4_DECOMPRESS if EROFS_FS_ZIP
+	select XXHASH if EROFS_FS_XATTR
+	select XZ_DEC if EROFS_FS_ZIP_LZMA
+	select XZ_DEC_MICROLZMA if EROFS_FS_ZIP_LZMA
+	select ZLIB_INFLATE if EROFS_FS_ZIP_DEFLATE
+	select ZSTD_DECOMPRESS if EROFS_FS_ZIP_ZSTD
+	help
+	  EROFS (Enhanced Read-Only File System) is a modern, lightweight,
+	  secure read-only filesystem for various use cases, such as immutable
+	  system images, container images, application sandboxes, and datasets.
+
+	  EROFS uses a flexible, hierarchical on-disk design so that features
+	  can be enabled on demand: the core on-disk format is block-aligned in
+	  order to perform optimally on all kinds of devices, including block
+	  and memory-backed devices; the format is easy to parse and has zero
+	  metadata redundancy, unlike generic filesystems, making it ideal for
+	  filesystem auditing and remote access; inline data, random-access
+	  friendly directory data, inline/shared extended attributes and
+	  chunk-based deduplication ensure space efficiency while maintaining
+	  high performance.
+
+	  Optionally, it supports multiple devices to reference external data,
+	  enabling data sharing for container images.
+
+	  It also has advanced encoded on-disk layouts, particularly for data
+	  compression and fine-grained deduplication. It utilizes fixed-size
+	  output compression to improve storage density while keeping relatively
+	  high compression ratios. Furthermore, it implements in-place
+	  decompression to reuse file pages to keep compressed data temporarily
+	  with proper strategies, which ensures guaranteed end-to-end runtime
+	  performance under extreme memory pressure without extra cost.
+
+	  For more details, see the web pages at <https://erofs.docs.kernel.org>
+	  and the documentation at <file:Documentation/filesystems/erofs.rst>.
+
+	  To compile EROFS filesystem support as a module, choose M here. The
+	  module will be called erofs.
+
+	  If unsure, say N.
+
+config EROFS_FS_DEBUG
+	bool "EROFS debugging feature"
+	depends on EROFS_FS
+	help
+	  Print debugging messages and enable more BUG_ONs which check
+	  filesystem consistency and find potential issues aggressively,
+	  which can be used for Android eng build, for example.
+
+	  For daily use, say N.
+
+config EROFS_FS_XATTR
+	bool "EROFS extended attributes"
+	depends on EROFS_FS
+	default y
+	help
+	  Extended attributes are name:value pairs associated with inodes by
+	  the kernel or by users (see the attr(5) manual page, or visit
+	  <http://acl.bestbits.at/> for details).
+
+	  If unsure, say N.
+
+config EROFS_FS_POSIX_ACL
+	bool "EROFS Access Control Lists"
+	depends on EROFS_FS_XATTR
+	select FS_POSIX_ACL
+	default y
+	help
+	  Posix Access Control Lists (ACLs) support permissions for users and
+	  groups beyond the owner/group/world scheme.
+
+	  To learn more about Access Control Lists, visit the POSIX ACLs for
+	  Linux website <http://acl.bestbits.at/>.
+
+	  If you don't know what Access Control Lists are, say N.
+
+config EROFS_FS_SECURITY
+	bool "EROFS Security Labels"
+	depends on EROFS_FS_XATTR
+	default y
+	help
+	  Security labels provide an access control facility to support Linux
+	  Security Models (LSMs) accepted by AppArmor, SELinux, Smack and TOMOYO
+	  Linux. This option enables an extended attribute handler for file
+	  security labels in the erofs filesystem, so that it requires enabling
+	  the extended attribute support in advance.
+
+	  If you are not using a security module, say N.
+
+config EROFS_FS_BACKED_BY_FILE
+	bool "File-backed EROFS filesystem support"
+	depends on EROFS_FS
+	default y
+	help
+	  This allows EROFS to use filesystem image files directly, without
+	  the intercession of loopback block devices or likewise. It is
+	  particularly useful for container images with numerous blobs and
+	  other sandboxes, where loop devices behave intricately.  It can also
+	  be used to simplify error-prone lifetime management of unnecessary
+	  virtual block devices.
+
+	  If you don't want to enable this feature, say N.
+
+config EROFS_FS_ZIP
+	bool "EROFS Data Compression Support"
+	depends on EROFS_FS
+	default y
+	help
+	  Enable EROFS compression layouts so that filesystems containing
+	  compressed files can be parsed by the kernel.
+
+	  If you don't want to enable compression feature, say N.
+
+config EROFS_FS_ZIP_LZMA
+	bool "EROFS LZMA compressed data support"
+	depends on EROFS_FS_ZIP
+	default y
+	help
+	  Saying Y here includes support for reading EROFS file systems
+	  containing LZMA compressed data, specifically called microLZMA. It
+	  gives better compression ratios than the default LZ4 format, at the
+	  expense of more CPU overhead.
+
+	  Say N if you want to disable LZMA compression support.
+
+config EROFS_FS_ZIP_LZMA_DEFAULT_MAX_STREAMS
+	int "EROFS LZMA default maximum decompression streams"
+	depends on EROFS_FS_ZIP_LZMA
+	range 1 NR_CPUS if SMP
+	range 1 1 if !SMP
+	default 16
+	help
+	  By default EROFS allocates one LZMA decompression stream per CPU.
+	  Each stream can hold a dictionary of up to 8 MiB taken from the
+	  mounted image, so on systems with many CPUs this can reserve a lot
+	  of memory.  This caps the default; the lzma_streams module parameter
+	  still overrides it.
+
+	  If unsure, keep the default of 16.
+
+config EROFS_FS_ZIP_DEFLATE
+	bool "EROFS DEFLATE compressed data support"
+	depends on EROFS_FS_ZIP
+	help
+	  Saying Y here includes support for reading EROFS file systems
+	  containing DEFLATE compressed data.  It gives better compression
+	  ratios than the default LZ4 format, while it costs more CPU
+	  overhead.
+
+	  If unsure, say N.
+
+config EROFS_FS_ZIP_ZSTD
+	bool "EROFS Zstandard compressed data support"
+	depends on EROFS_FS_ZIP
+	help
+	  Saying Y here includes support for reading EROFS file systems
+	  containing Zstandard compressed data.  It gives better compression
+	  ratios than the default LZ4 format, while it costs more CPU
+	  overhead and memory footprint.
+
+	  If unsure, say N.
+
+config EROFS_FS_ZIP_ACCEL
+	bool "EROFS hardware decompression support"
+	depends on EROFS_FS_ZIP
+	help
+	  Saying Y here includes hardware accelerator support for reading
+	  EROFS file systems containing compressed data.  It gives better
+	  decompression speed than the software-implemented decompression, and
+	  it costs lower CPU overhead.
+
+	  Hardware accelerator support is an experimental feature for now and
+	  file systems are still readable without selecting this option.
+
+	  If unsure, say N.
+
+config EROFS_FS_PCPU_KTHREAD
+	bool "EROFS per-cpu decompression kthread workers"
+	depends on EROFS_FS_ZIP
+	help
+	  Saying Y here enables per-CPU kthread workers pool to carry out
+	  async decompression for low latencies on some architectures.
+
+	  If unsure, say N.
+
+config EROFS_FS_PCPU_KTHREAD_HIPRI
+	bool "EROFS high priority per-CPU kthread workers"
+	depends on EROFS_FS_ZIP && EROFS_FS_PCPU_KTHREAD
+	default y
+	help
+	  This permits EROFS to configure per-CPU kthread workers to run
+	  at higher priority.
+
+	  If unsure, say N.
+
+config EROFS_FS_PAGE_CACHE_SHARE
+	bool "EROFS page cache share support (experimental)"
+	depends on EROFS_FS && EROFS_FS_XATTR
+	select FS_STACK
+	help
+	  This enables page cache sharing among inodes with identical
+	  content fingerprints on the same machine.
+
+	  If unsure, say N.