1# SPDX-License-Identifier: GPL-2.0-only 2 3config EROFS_FS 4 tristate "EROFS filesystem support" 5 depends on BLOCK 6 help 7 EROFS (Enhanced Read-Only File System) is a lightweight 8 read-only file system with modern designs (eg. page-sized 9 blocks, inline xattrs/data, etc.) for scenarios which need 10 high-performance read-only requirements, e.g. Android OS 11 for mobile phones and LIVECDs. 12 13 It also provides fixed-sized output compression support, 14 which improves storage density, keeps relatively higher 15 compression ratios, which is more useful to achieve high 16 performance for embedded devices with limited memory. 17 18 If unsure, say N. 19 20config EROFS_FS_DEBUG 21 bool "EROFS debugging feature" 22 depends on EROFS_FS 23 help 24 Print debugging messages and enable more BUG_ONs which check 25 filesystem consistency and find potential issues aggressively, 26 which can be used for Android eng build, for example. 27 28 For daily use, say N. 29 30config EROFS_FS_XATTR 31 bool "EROFS extended attributes" 32 depends on EROFS_FS 33 default y 34 help 35 Extended attributes are name:value pairs associated with inodes by 36 the kernel or by users (see the attr(5) manual page, or visit 37 <http://acl.bestbits.at/> for details). 38 39 If unsure, say N. 40 41config EROFS_FS_POSIX_ACL 42 bool "EROFS Access Control Lists" 43 depends on EROFS_FS_XATTR 44 select FS_POSIX_ACL 45 default y 46 help 47 Posix Access Control Lists (ACLs) support permissions for users and 48 groups beyond the owner/group/world scheme. 49 50 To learn more about Access Control Lists, visit the POSIX ACLs for 51 Linux website <http://acl.bestbits.at/>. 52 53 If you don't know what Access Control Lists are, say N. 54 55config EROFS_FS_SECURITY 56 bool "EROFS Security Labels" 57 depends on EROFS_FS_XATTR 58 default y 59 help 60 Security labels provide an access control facility to support Linux 61 Security Models (LSMs) accepted by AppArmor, SELinux, Smack and TOMOYO 62 Linux. This option enables an extended attribute handler for file 63 security labels in the erofs filesystem, so that it requires enabling 64 the extended attribute support in advance. 65 66 If you are not using a security module, say N. 67 68config EROFS_FS_ZIP 69 bool "EROFS Data Compression Support" 70 depends on EROFS_FS 71 select LZ4_DECOMPRESS 72 default y 73 help 74 Enable fixed-sized output compression for EROFS. 75 76 If you don't want to enable compression feature, say N. 77 78config EROFS_FS_CLUSTER_PAGE_LIMIT 79 int "EROFS Cluster Pages Hard Limit" 80 depends on EROFS_FS_ZIP 81 range 1 256 82 default "1" 83 help 84 Indicates maximum # of pages of a compressed 85 physical cluster. 86 87 For example, if files in a image were compressed 88 into 8k-unit, hard limit should not be configured 89 less than 2. Otherwise, the image will be refused 90 to mount on this kernel. 91 92