Let's enable long xattr name prefix feature. Old kernels will just
ignore / skip such extended attributes so that in case you don't want
to mount such images. Add another incompatible feature as an option
for this.
Signed-off-by: Jingbo Xu <jeffl...@linux.alibaba.com>
---
fs/erofs/erofs_fs.h | 4 +++-
fs/erofs/internal.h | 1 +
fs/erofs/super.c | 8 ++++++++
3 files changed, 12 insertions(+), 1 deletion(-)
diff --git a/fs/erofs/erofs_fs.h b/fs/erofs/erofs_fs.h
index ea62f83dac40..ac42a7255b39 100644
--- a/fs/erofs/erofs_fs.h
+++ b/fs/erofs/erofs_fs.h
@@ -27,6 +27,7 @@
#define EROFS_FEATURE_INCOMPAT_ZTAILPACKING 0x00000010
#define EROFS_FEATURE_INCOMPAT_FRAGMENTS 0x00000020
#define EROFS_FEATURE_INCOMPAT_DEDUPE 0x00000020
+#define EROFS_FEATURE_INCOMPAT_XATTR_PREFIXES 0x00000040
#define EROFS_ALL_FEATURE_INCOMPAT \
(EROFS_FEATURE_INCOMPAT_ZERO_PADDING | \
EROFS_FEATURE_INCOMPAT_COMPR_CFGS | \
@@ -36,7 +37,8 @@
EROFS_FEATURE_INCOMPAT_COMPR_HEAD2 | \
EROFS_FEATURE_INCOMPAT_ZTAILPACKING | \
EROFS_FEATURE_INCOMPAT_FRAGMENTS | \
- EROFS_FEATURE_INCOMPAT_DEDUPE)
+ EROFS_FEATURE_INCOMPAT_DEDUPE | \
+ EROFS_FEATURE_INCOMPAT_XATTR_PREFIXES)
#define EROFS_SB_EXTSLOT_SIZE 16
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 5a9c19654b19..f675050af2bb 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -285,6 +285,7 @@ EROFS_FEATURE_FUNCS(compr_head2, incompat,
INCOMPAT_COMPR_HEAD2)
EROFS_FEATURE_FUNCS(ztailpacking, incompat, INCOMPAT_ZTAILPACKING)
EROFS_FEATURE_FUNCS(fragments, incompat, INCOMPAT_FRAGMENTS)
EROFS_FEATURE_FUNCS(dedupe, incompat, INCOMPAT_DEDUPE)
+EROFS_FEATURE_FUNCS(xattr_prefixes, incompat, INCOMPAT_XATTR_PREFIXES)
EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
/* atomic flag definitions */
diff --git a/fs/erofs/super.c b/fs/erofs/super.c
index bf396e0c243a..8f85cc6162e2 100644
--- a/fs/erofs/super.c
+++ b/fs/erofs/super.c
@@ -391,6 +391,9 @@ static int erofs_read_superblock(struct super_block *sb)
sbi->packed_nid = le64_to_cpu(dsb->packed_nid);
sbi->inos = le64_to_cpu(dsb->inos);
+ sbi->xattr_prefix_start = le32_to_cpu(dsb->xattr_prefix_start);
+ sbi->xattr_prefix_count = dsb->xattr_prefix_count;
+
sbi->build_time = le64_to_cpu(dsb->build_time);
sbi->build_time_nsec = le32_to_cpu(dsb->build_time_nsec);
@@ -822,6 +825,10 @@ static int erofs_fc_fill_super(struct super_block *sb,
struct fs_context *fc)
if (err)
return err;
+ err = erofs_xattr_prefixes_init(sb);
+ if (err)
+ return err;
+
err = erofs_register_sysfs(sb);
if (err)
return err;
@@ -981,6 +988,7 @@ static void erofs_put_super(struct super_block *sb)
erofs_unregister_sysfs(sb);
erofs_shrinker_unregister(sb);
+ erofs_xattr_prefixes_cleanup(sb);
#ifdef CONFIG_EROFS_FS_ZIP
iput(sbi->managed_cache);
sbi->managed_cache = NULL;
--
2.19.1.6.gb485710b
