[RFC PATCH 1/4] fs: Add FS_XFLAG_COMPRESSED & FS_XFLAG_ENCRYPTED for FS_IOC_FS[GS]ETXATTR API

From: Pali Rohár
Date: Sun Feb 16 2025 - 11:42:52 EST


This allows to get or set FS_COMPR_FL and FS_ENCRYPT_FL bits via FS_IOC_FSGETXATTR/FS_IOC_FSSETXATTR API.

Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
---
fs/ioctl.c | 8 ++++++++
include/linux/fileattr.h | 4 ++--
include/uapi/linux/fs.h | 2 ++
3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/fs/ioctl.c b/fs/ioctl.c
index 638a36be31c1..9f3609b50779 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -480,6 +480,10 @@ void fileattr_fill_xflags(struct fileattr *fa, u32 xflags)
fa->flags |= FS_DAX_FL;
if (fa->fsx_xflags & FS_XFLAG_PROJINHERIT)
fa->flags |= FS_PROJINHERIT_FL;
+ if (fa->fsx_xflags & FS_XFLAG_COMPRESSED)
+ fa->flags |= FS_COMPR_FL;
+ if (fa->fsx_xflags & FS_XFLAG_ENCRYPTED)
+ fa->flags |= FS_ENCRYPT_FL;
}
EXPORT_SYMBOL(fileattr_fill_xflags);

@@ -496,6 +500,8 @@ void fileattr_fill_flags(struct fileattr *fa, u32 flags)
memset(fa, 0, sizeof(*fa));
fa->flags_valid = true;
fa->flags = flags;
+ if (fa->flags & FS_COMPR_FL)
+ fa->fsx_xflags |= FS_XFLAG_COMPRESSED;
if (fa->flags & FS_SYNC_FL)
fa->fsx_xflags |= FS_XFLAG_SYNC;
if (fa->flags & FS_IMMUTABLE_FL)
@@ -506,6 +512,8 @@ void fileattr_fill_flags(struct fileattr *fa, u32 flags)
fa->fsx_xflags |= FS_XFLAG_NODUMP;
if (fa->flags & FS_NOATIME_FL)
fa->fsx_xflags |= FS_XFLAG_NOATIME;
+ if (fa->flags & FS_ENCRYPT_FL)
+ fa->fsx_xflags |= FS_XFLAG_ENCRYPTED;
if (fa->flags & FS_DAX_FL)
fa->fsx_xflags |= FS_XFLAG_DAX;
if (fa->flags & FS_PROJINHERIT_FL)
diff --git a/include/linux/fileattr.h b/include/linux/fileattr.h
index 47c05a9851d0..c297e6151703 100644
--- a/include/linux/fileattr.h
+++ b/include/linux/fileattr.h
@@ -7,12 +7,12 @@
#define FS_COMMON_FL \
(FS_SYNC_FL | FS_IMMUTABLE_FL | FS_APPEND_FL | \
FS_NODUMP_FL | FS_NOATIME_FL | FS_DAX_FL | \
- FS_PROJINHERIT_FL)
+ FS_PROJINHERIT_FL | FS_COMPR_FL | FS_ENCRYPT_FL)

#define FS_XFLAG_COMMON \
(FS_XFLAG_SYNC | FS_XFLAG_IMMUTABLE | FS_XFLAG_APPEND | \
FS_XFLAG_NODUMP | FS_XFLAG_NOATIME | FS_XFLAG_DAX | \
- FS_XFLAG_PROJINHERIT)
+ FS_XFLAG_PROJINHERIT | FS_XFLAG_COMPRESSED | FS_XFLAG_ENCRYPTED)

/*
* Merged interface for miscellaneous file attributes. 'flags' originates from
diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h
index 2bbe00cf1248..367bc5289c47 100644
--- a/include/uapi/linux/fs.h
+++ b/include/uapi/linux/fs.h
@@ -167,6 +167,8 @@ struct fsxattr {
#define FS_XFLAG_FILESTREAM 0x00004000 /* use filestream allocator */
#define FS_XFLAG_DAX 0x00008000 /* use DAX for IO */
#define FS_XFLAG_COWEXTSIZE 0x00010000 /* CoW extent size allocator hint */
+#define FS_XFLAG_COMPRESSED 0x00020000 /* compressed file */
+#define FS_XFLAG_ENCRYPTED 0x00040000 /* encrypted file */
#define FS_XFLAG_HASATTR 0x80000000 /* no DIFLAG for this */

/* the read-only stuff doesn't really belong here, but any other place is
--
2.20.1