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 <<
7 select LIBCRC32C 6 select LIBCRC32C
8 help 7 help
9 EROFS (Enhanced Read-Only File Syste !! 8 EROFS (Enhanced Read-Only File System) is a lightweight
10 file system with modern designs (e.g !! 9 read-only file system with modern designs (eg. page-sized
11 xattrs/data, chunk-based deduplicati !! 10 blocks, inline xattrs/data, etc.) for scenarios which need
12 scenarios which need high-performanc !! 11 high-performance read-only requirements, e.g. Android OS
13 smartphones with Android OS, LiveCDs !! 12 for mobile phones and LIVECDs.
14 numerous containers; !! 13
15 !! 14 It also provides fixed-sized output compression support,
16 It also provides fixed-sized output !! 15 which improves storage density, keeps relatively higher
17 improve storage density as well as k !! 16 compression ratios, which is more useful to achieve high
18 ratios and implements in-place decom !! 17 performance for embedded devices with limited memory.
19 for compressed data temporarily with <<
20 quite useful to ensure guaranteed en <<
21 performance under extremely memory p <<
22 <<
23 See the documentation at <file:Docum <<
24 and the web pages at <https://erofs. <<
25 18
26 If unsure, say N. 19 If unsure, say N.
27 20
28 config EROFS_FS_DEBUG 21 config EROFS_FS_DEBUG
29 bool "EROFS debugging feature" 22 bool "EROFS debugging feature"
30 depends on EROFS_FS 23 depends on EROFS_FS
31 help 24 help
32 Print debugging messages and enable 25 Print debugging messages and enable more BUG_ONs which check
33 filesystem consistency and find pote 26 filesystem consistency and find potential issues aggressively,
34 which can be used for Android eng bu 27 which can be used for Android eng build, for example.
35 28
36 For daily use, say N. 29 For daily use, say N.
37 30
38 config EROFS_FS_XATTR 31 config EROFS_FS_XATTR
39 bool "EROFS extended attributes" 32 bool "EROFS extended attributes"
40 depends on EROFS_FS 33 depends on EROFS_FS
41 select XXHASH <<
42 default y 34 default y
43 help 35 help
44 Extended attributes are name:value p 36 Extended attributes are name:value pairs associated with inodes by
45 the kernel or by users (see the attr 37 the kernel or by users (see the attr(5) manual page, or visit
46 <http://acl.bestbits.at/> for detail 38 <http://acl.bestbits.at/> for details).
47 39
48 If unsure, say N. 40 If unsure, say N.
49 41
50 config EROFS_FS_POSIX_ACL 42 config EROFS_FS_POSIX_ACL
51 bool "EROFS Access Control Lists" 43 bool "EROFS Access Control Lists"
52 depends on EROFS_FS_XATTR 44 depends on EROFS_FS_XATTR
53 select FS_POSIX_ACL 45 select FS_POSIX_ACL
54 default y 46 default y
55 help 47 help
56 Posix Access Control Lists (ACLs) su 48 Posix Access Control Lists (ACLs) support permissions for users and
57 groups beyond the owner/group/world 49 groups beyond the owner/group/world scheme.
58 50
59 To learn more about Access Control L 51 To learn more about Access Control Lists, visit the POSIX ACLs for
60 Linux website <http://acl.bestbits.a 52 Linux website <http://acl.bestbits.at/>.
61 53
62 If you don't know what Access Contro 54 If you don't know what Access Control Lists are, say N.
63 55
64 config EROFS_FS_SECURITY 56 config EROFS_FS_SECURITY
65 bool "EROFS Security Labels" 57 bool "EROFS Security Labels"
66 depends on EROFS_FS_XATTR 58 depends on EROFS_FS_XATTR
67 default y 59 default y
68 help 60 help
69 Security labels provide an access co 61 Security labels provide an access control facility to support Linux
70 Security Models (LSMs) accepted by A 62 Security Models (LSMs) accepted by AppArmor, SELinux, Smack and TOMOYO
71 Linux. This option enables an extend 63 Linux. This option enables an extended attribute handler for file
72 security labels in the erofs filesys 64 security labels in the erofs filesystem, so that it requires enabling
73 the extended attribute support in ad 65 the extended attribute support in advance.
74 66
75 If you are not using a security modu 67 If you are not using a security module, say N.
76 68
77 config EROFS_FS_ZIP 69 config EROFS_FS_ZIP
78 bool "EROFS Data Compression Support" 70 bool "EROFS Data Compression Support"
79 depends on EROFS_FS 71 depends on EROFS_FS
80 select LZ4_DECOMPRESS 72 select LZ4_DECOMPRESS
81 default y 73 default y
82 help 74 help
83 Enable fixed-sized output compressio 75 Enable fixed-sized output compression for EROFS.
84 76
85 If you don't want to enable compress 77 If you don't want to enable compression feature, say N.
86 78
87 config EROFS_FS_ZIP_LZMA !! 79 config EROFS_FS_CLUSTER_PAGE_LIMIT
88 bool "EROFS LZMA compressed data suppo !! 80 int "EROFS Cluster Pages Hard Limit"
89 depends on EROFS_FS_ZIP <<
90 select XZ_DEC <<
91 select XZ_DEC_MICROLZMA <<
92 help <<
93 Saying Y here includes support for r <<
94 containing LZMA compressed data, spe <<
95 gives better compression ratios than <<
96 expense of more CPU overhead. <<
97 <<
98 If unsure, say N. <<
99 <<
100 config EROFS_FS_ZIP_DEFLATE <<
101 bool "EROFS DEFLATE compressed data su <<
102 depends on EROFS_FS_ZIP <<
103 select ZLIB_INFLATE <<
104 help <<
105 Saying Y here includes support for r <<
106 containing DEFLATE compressed data. <<
107 ratios than the default LZ4 format, <<
108 overhead. <<
109 <<
110 DEFLATE support is an experimental f <<
111 file systems will be readable withou <<
112 <<
113 If unsure, say N. <<
114 <<
115 config EROFS_FS_ZIP_ZSTD <<
116 bool "EROFS Zstandard compressed data <<
117 depends on EROFS_FS_ZIP <<
118 select ZSTD_DECOMPRESS <<
119 help <<
120 Saying Y here includes support for r <<
121 containing Zstandard compressed data <<
122 ratios than the default LZ4 format, <<
123 overhead. <<
124 <<
125 Zstandard support is an experimental <<
126 file systems will be readable withou <<
127 <<
128 If unsure, say N. <<
129 <<
130 config EROFS_FS_ONDEMAND <<
131 bool "EROFS fscache-based on-demand re <<
132 depends on EROFS_FS <<
133 select NETFS_SUPPORT <<
134 select FSCACHE <<
135 select CACHEFILES <<
136 select CACHEFILES_ONDEMAND <<
137 help <<
138 This permits EROFS to use fscache-ba <<
139 read support. <<
140 <<
141 If unsure, say N. <<
142 <<
143 config EROFS_FS_PCPU_KTHREAD <<
144 bool "EROFS per-cpu decompression kthr <<
145 depends on EROFS_FS_ZIP 81 depends on EROFS_FS_ZIP
>> 82 range 1 256
>> 83 default "1"
146 help 84 help
147 Saying Y here enables per-CPU kthrea !! 85 Indicates maximum # of pages of a compressed
148 async decompression for low latencie !! 86 physical cluster.
149 87
150 If unsure, say N. !! 88 For example, if files in a image were compressed
>> 89 into 8k-unit, hard limit should not be configured
>> 90 less than 2. Otherwise, the image will be refused
>> 91 to mount on this kernel.
151 92
152 config EROFS_FS_PCPU_KTHREAD_HIPRI <<
153 bool "EROFS high priority per-CPU kthr <<
154 depends on EROFS_FS_ZIP && EROFS_FS_PC <<
155 default y <<
156 help <<
157 This permits EROFS to configure per- <<
158 at higher priority. <<
159 <<
160 If unsure, say N. <<
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