From: "Dr. David Alan Gilbert" <dgilbert@xxxxxxxxxx>
This new FUSE_INIT field communicates the alignment constraint for
FUSE_SETUPMAPPING/FUSE_REMOVEMAPPING and allows the daemon to
constrain the addresses and file offsets chosen by the kernel.
Signed-off-by: Stefan Hajnoczi <stefanha@xxxxxxxxxx>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@xxxxxxxxxx>
---
include/uapi/linux/fuse.h | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h
index f14eeb5cfc14..65c2136d112e 100644
--- a/include/uapi/linux/fuse.h
+++ b/include/uapi/linux/fuse.h
@@ -134,6 +134,7 @@
* 7.31
* - add FUSE_WRITE_KILL_PRIV flag
* - add FUSE_SETUPMAPPING and FUSE_REMOVEMAPPING
+ * - add map_alignment to fuse_init_out
*/
#ifndef _LINUX_FUSE_H
@@ -275,6 +276,9 @@ struct fuse_file_lock {
* FUSE_CACHE_SYMLINKS: cache READLINK responses
* FUSE_NO_OPENDIR_SUPPORT: kernel supports zero-message opendir
* FUSE_EXPLICIT_INVAL_DATA: only invalidate cached pages on explicit request
+ * FUSE_MAP_ALIGNMENT: init_out.map_alignment contains log2(byte alignment) for
+ * foffset and moffset fields in struct
+ * fuse_setupmapping_in and fuse_removemapping_one.
*/
#define FUSE_ASYNC_READ (1 << 0)
#define FUSE_POSIX_LOCKS (1 << 1)
@@ -302,6 +306,8 @@ struct fuse_file_lock {
#define FUSE_CACHE_SYMLINKS (1 << 23)
#define FUSE_NO_OPENDIR_SUPPORT (1 << 24)
#define FUSE_EXPLICIT_INVAL_DATA (1 << 25)
+#define FUSE_MAP_ALIGNMENT (1 << 26)
+
/**
* CUSE INIT request/reply flags
@@ -655,7 +661,7 @@ struct fuse_init_out {
uint32_t max_write;
uint32_t time_gran;
uint16_t max_pages;
- uint16_t padding;
+ uint16_t map_alignment;
uint32_t unused[8];
};
--
2.21.0
