1 # SPDX-License-Identifier: GPL-2.0-only 1 # SPDX-License-Identifier: GPL-2.0-only 2 2 3 config EROFS_FS 3 config EROFS_FS 4 tristate "EROFS filesystem support" 4 tristate "EROFS filesystem support" 5 depends on BLOCK 5 depends on BLOCK 6 select FS_IOMAP 6 select FS_IOMAP 7 select LIBCRC32C 7 select LIBCRC32C 8 help 8 help 9 EROFS (Enhanced Read-Only File Syste 9 EROFS (Enhanced Read-Only File System) is a lightweight read-only 10 file system with modern designs (e.g 10 file system with modern designs (e.g. no buffer heads, inline 11 xattrs/data, chunk-based deduplicati 11 xattrs/data, chunk-based deduplication, multiple devices, etc.) for 12 scenarios which need high-performanc 12 scenarios which need high-performance read-only solutions, e.g. 13 smartphones with Android OS, LiveCDs 13 smartphones with Android OS, LiveCDs and high-density hosts with 14 numerous containers; 14 numerous containers; 15 15 16 It also provides fixed-sized output 16 It also provides fixed-sized output compression support in order to 17 improve storage density as well as k 17 improve storage density as well as keep relatively higher compression 18 ratios and implements in-place decom 18 ratios and implements in-place decompression to reuse the file page 19 for compressed data temporarily with 19 for compressed data temporarily with proper strategies, which is 20 quite useful to ensure guaranteed en 20 quite useful to ensure guaranteed end-to-end runtime decompression 21 performance under extremely memory p 21 performance under extremely memory pressure without extra cost. 22 22 23 See the documentation at <file:Docum 23 See the documentation at <file:Documentation/filesystems/erofs.rst> 24 and the web pages at <https://erofs. 24 and the web pages at <https://erofs.docs.kernel.org> for more details. 25 25 26 If unsure, say N. 26 If unsure, say N. 27 27 28 config EROFS_FS_DEBUG 28 config EROFS_FS_DEBUG 29 bool "EROFS debugging feature" 29 bool "EROFS debugging feature" 30 depends on EROFS_FS 30 depends on EROFS_FS 31 help 31 help 32 Print debugging messages and enable 32 Print debugging messages and enable more BUG_ONs which check 33 filesystem consistency and find pote 33 filesystem consistency and find potential issues aggressively, 34 which can be used for Android eng bu 34 which can be used for Android eng build, for example. 35 35 36 For daily use, say N. 36 For daily use, say N. 37 37 38 config EROFS_FS_XATTR 38 config EROFS_FS_XATTR 39 bool "EROFS extended attributes" 39 bool "EROFS extended attributes" 40 depends on EROFS_FS 40 depends on EROFS_FS 41 select XXHASH 41 select XXHASH 42 default y 42 default y 43 help 43 help 44 Extended attributes are name:value p 44 Extended attributes are name:value pairs associated with inodes by 45 the kernel or by users (see the attr 45 the kernel or by users (see the attr(5) manual page, or visit 46 <http://acl.bestbits.at/> for detail 46 <http://acl.bestbits.at/> for details). 47 47 48 If unsure, say N. 48 If unsure, say N. 49 49 50 config EROFS_FS_POSIX_ACL 50 config EROFS_FS_POSIX_ACL 51 bool "EROFS Access Control Lists" 51 bool "EROFS Access Control Lists" 52 depends on EROFS_FS_XATTR 52 depends on EROFS_FS_XATTR 53 select FS_POSIX_ACL 53 select FS_POSIX_ACL 54 default y 54 default y 55 help 55 help 56 Posix Access Control Lists (ACLs) su 56 Posix Access Control Lists (ACLs) support permissions for users and 57 groups beyond the owner/group/world 57 groups beyond the owner/group/world scheme. 58 58 59 To learn more about Access Control L 59 To learn more about Access Control Lists, visit the POSIX ACLs for 60 Linux website <http://acl.bestbits.a 60 Linux website <http://acl.bestbits.at/>. 61 61 62 If you don't know what Access Contro 62 If you don't know what Access Control Lists are, say N. 63 63 64 config EROFS_FS_SECURITY 64 config EROFS_FS_SECURITY 65 bool "EROFS Security Labels" 65 bool "EROFS Security Labels" 66 depends on EROFS_FS_XATTR 66 depends on EROFS_FS_XATTR 67 default y 67 default y 68 help 68 help 69 Security labels provide an access co 69 Security labels provide an access control facility to support Linux 70 Security Models (LSMs) accepted by A 70 Security Models (LSMs) accepted by AppArmor, SELinux, Smack and TOMOYO 71 Linux. This option enables an extend 71 Linux. This option enables an extended attribute handler for file 72 security labels in the erofs filesys 72 security labels in the erofs filesystem, so that it requires enabling 73 the extended attribute support in ad 73 the extended attribute support in advance. 74 74 75 If you are not using a security modu 75 If you are not using a security module, say N. 76 76 77 config EROFS_FS_BACKED_BY_FILE << 78 bool "File-backed EROFS filesystem sup << 79 depends on EROFS_FS << 80 default y << 81 help << 82 This allows EROFS to use filesystem << 83 the intercession of loopback block d << 84 particularly useful for container im << 85 other sandboxes, where loop devices << 86 be used to simplify error-prone life << 87 virtual block devices. << 88 << 89 Note that this feature, along with o << 90 hooks, will eventually replace "EROF << 91 << 92 If you don't want to enable this fea << 93 << 94 config EROFS_FS_ZIP 77 config EROFS_FS_ZIP 95 bool "EROFS Data Compression Support" 78 bool "EROFS Data Compression Support" 96 depends on EROFS_FS 79 depends on EROFS_FS 97 select LZ4_DECOMPRESS 80 select LZ4_DECOMPRESS 98 default y 81 default y 99 help 82 help 100 Enable fixed-sized output compressio 83 Enable fixed-sized output compression for EROFS. 101 84 102 If you don't want to enable compress 85 If you don't want to enable compression feature, say N. 103 86 104 config EROFS_FS_ZIP_LZMA 87 config EROFS_FS_ZIP_LZMA 105 bool "EROFS LZMA compressed data suppo 88 bool "EROFS LZMA compressed data support" 106 depends on EROFS_FS_ZIP 89 depends on EROFS_FS_ZIP 107 select XZ_DEC 90 select XZ_DEC 108 select XZ_DEC_MICROLZMA 91 select XZ_DEC_MICROLZMA 109 help 92 help 110 Saying Y here includes support for r 93 Saying Y here includes support for reading EROFS file systems 111 containing LZMA compressed data, spe 94 containing LZMA compressed data, specifically called microLZMA. It 112 gives better compression ratios than 95 gives better compression ratios than the default LZ4 format, at the 113 expense of more CPU overhead. 96 expense of more CPU overhead. 114 97 115 If unsure, say N. 98 If unsure, say N. 116 99 117 config EROFS_FS_ZIP_DEFLATE 100 config EROFS_FS_ZIP_DEFLATE 118 bool "EROFS DEFLATE compressed data su 101 bool "EROFS DEFLATE compressed data support" 119 depends on EROFS_FS_ZIP 102 depends on EROFS_FS_ZIP 120 select ZLIB_INFLATE 103 select ZLIB_INFLATE 121 help 104 help 122 Saying Y here includes support for r 105 Saying Y here includes support for reading EROFS file systems 123 containing DEFLATE compressed data. 106 containing DEFLATE compressed data. It gives better compression 124 ratios than the default LZ4 format, 107 ratios than the default LZ4 format, while it costs more CPU 125 overhead. 108 overhead. 126 109 127 DEFLATE support is an experimental f 110 DEFLATE support is an experimental feature for now and so most 128 file systems will be readable withou 111 file systems will be readable without selecting this option. 129 112 130 If unsure, say N. 113 If unsure, say N. 131 114 132 config EROFS_FS_ZIP_ZSTD << 133 bool "EROFS Zstandard compressed data << 134 depends on EROFS_FS_ZIP << 135 select ZSTD_DECOMPRESS << 136 help << 137 Saying Y here includes support for r << 138 containing Zstandard compressed data << 139 ratios than the default LZ4 format, << 140 overhead. << 141 << 142 Zstandard support is an experimental << 143 file systems will be readable withou << 144 << 145 If unsure, say N. << 146 << 147 config EROFS_FS_ONDEMAND 115 config EROFS_FS_ONDEMAND 148 bool "EROFS fscache-based on-demand re !! 116 bool "EROFS fscache-based on-demand read support" 149 depends on EROFS_FS !! 117 depends on CACHEFILES_ONDEMAND && (EROFS_FS=m && FSCACHE || EROFS_FS=y && FSCACHE=y) 150 select NETFS_SUPPORT !! 118 default n 151 select FSCACHE << 152 select CACHEFILES << 153 select CACHEFILES_ONDEMAND << 154 help 119 help 155 This permits EROFS to use fscache-ba 120 This permits EROFS to use fscache-backed data blobs with on-demand 156 read support. 121 read support. 157 << 158 It is now deprecated and scheduled t << 159 after fanotify pre-content hooks are << 160 122 161 If unsure, say N. 123 If unsure, say N. 162 124 163 config EROFS_FS_PCPU_KTHREAD 125 config EROFS_FS_PCPU_KTHREAD 164 bool "EROFS per-cpu decompression kthr 126 bool "EROFS per-cpu decompression kthread workers" 165 depends on EROFS_FS_ZIP 127 depends on EROFS_FS_ZIP 166 help 128 help 167 Saying Y here enables per-CPU kthrea 129 Saying Y here enables per-CPU kthread workers pool to carry out 168 async decompression for low latencie 130 async decompression for low latencies on some architectures. 169 131 170 If unsure, say N. 132 If unsure, say N. 171 133 172 config EROFS_FS_PCPU_KTHREAD_HIPRI 134 config EROFS_FS_PCPU_KTHREAD_HIPRI 173 bool "EROFS high priority per-CPU kthr 135 bool "EROFS high priority per-CPU kthread workers" 174 depends on EROFS_FS_ZIP && EROFS_FS_PC 136 depends on EROFS_FS_ZIP && EROFS_FS_PCPU_KTHREAD 175 default y 137 default y 176 help 138 help 177 This permits EROFS to configure per- 139 This permits EROFS to configure per-CPU kthread workers to run 178 at higher priority. 140 at higher priority. 179 141 180 If unsure, say N. 142 If unsure, say N.
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.