[PATCH 02/67] vfs: Provide S_KERNEL_FILE inode flag

David Howells
2021-10-18T14:51:24Z

Provide an S_KERNEL_FILE inode flag that a kernel service, e.g. cachefiles,
can set to ward off other kernel services and drivers (including itself)
from using files it is actively using.

Signed-off-by: David Howells <dhowells@redhat.com>
---

include/linux/fs.h | 1 +
1 file changed, 1 insertion(+)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index e7a633353fd2..197493507744 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2250,6 +2250,7 @@ struct super_operations {
#define S_ENCRYPTED (1 << 14) /* Encrypted file (using fs/crypto/) */
#define S_CASEFOLD (1 << 15) /* Casefolded file */
#define S_VERITY (1 << 16) /* Verity file (using fs/verity/) */
+#define S_KERNEL_FILE (1 << 17) /* File is in use by the kernel (eg. fs/cachefiles) */

/*
* Note that nosuid etc flags are inode-specific: setting some file-system