[PATCH v2 20/30] fuse: Introduce setupmapping/removemapping commands

From: Vivek Goyal
Date: Wed May 15 2019 - 15:32:21 EST


Introduce two new fuse commands to setup/remove memory mappings. This
will be used to setup/tear down file mapping in dax window.

Signed-off-by: Vivek Goyal <vgoyal@xxxxxxxxxx>
---
include/uapi/linux/fuse.h | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)

diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h
index 2ac598614a8f..9eb313220549 100644
--- a/include/uapi/linux/fuse.h
+++ b/include/uapi/linux/fuse.h
@@ -399,6 +399,8 @@ enum fuse_opcode {
FUSE_RENAME2 = 45,
FUSE_LSEEK = 46,
FUSE_COPY_FILE_RANGE = 47,
+ FUSE_SETUPMAPPING = 48,
+ FUSE_REMOVEMAPPING = 49,

/* CUSE specific operations */
CUSE_INIT = 4096,
@@ -822,4 +824,35 @@ struct fuse_copy_file_range_in {
uint64_t flags;
};

+#define FUSE_SETUPMAPPING_ENTRIES 8
+#define FUSE_SETUPMAPPING_FLAG_WRITE (1ull << 0)
+struct fuse_setupmapping_in {
+ /* An already open handle */
+ uint64_t fh;
+ /* Offset into the file to start the mapping */
+ uint64_t foffset;
+ /* Length of mapping required */
+ uint64_t len;
+ /* Flags, FUSE_SETUPMAPPING_FLAG_* */
+ uint64_t flags;
+ /* Offset in Memory Window */
+ uint64_t moffset;
+};
+
+struct fuse_setupmapping_out {
+ /* Offsets into the cache of mappings */
+ uint64_t coffset[FUSE_SETUPMAPPING_ENTRIES];
+ /* Lengths of each mapping */
+ uint64_t len[FUSE_SETUPMAPPING_ENTRIES];
+};
+
+struct fuse_removemapping_in {
+ /* An already open handle */
+ uint64_t fh;
+ /* Offset into the dax window start the unmapping */
+ uint64_t moffset;
+ /* Length of mapping required */
+ uint64_t len;
+};
+
#endif /* _LINUX_FUSE_H */
--
2.20.1