@@ -28,6 +28,7 @@ MODULE_ALIAS("devname:fuse");
/* Ordinary requests have even IDs, while interrupts IDs are odd */
#define FUSE_INT_REQ_BIT (1ULL << 0)
#define FUSE_REQ_ID_STEP (1ULL << 1)
+#define FUSE_REQ_ID_MASK (~(FUSE_INT_REQ_BIT | FUSE_UNIQUE_RESEND))
static struct kmem_cache *fuse_req_cachep;
@@ -194,7 +195,7 @@ EXPORT_SYMBOL_GPL(fuse_len_args);
u64 fuse_get_unique(struct fuse_iqueue *fiq)
{
- fiq->reqctr += FUSE_REQ_ID_STEP;
+ fiq->reqctr = (fiq->reqctr + FUSE_REQ_ID_STEP) & FUSE_REQ_ID_MASK;
return fiq->reqctr;
}
EXPORT_SYMBOL_GPL(fuse_get_unique);
@@ -1822,6 +1823,8 @@ static void fuse_resend(struct fuse_conn *fc)
list_for_each_entry_safe(req, next, &to_queue, list) {
__set_bit(FR_PENDING, &req->flags);
+ /* mark the request as resend request */
+ req->in.h.unique |= FUSE_UNIQUE_RESEND;
}
spin_lock(&fiq->lock);
@@ -1330,7 +1330,8 @@ void fuse_send_init(struct fuse_mount *fm)
FUSE_NO_OPENDIR_SUPPORT | FUSE_EXPLICIT_INVAL_DATA |
FUSE_HANDLE_KILLPRIV_V2 | FUSE_SETXATTR_EXT | FUSE_INIT_EXT |
FUSE_SECURITY_CTX | FUSE_CREATE_SUPP_GROUP |
- FUSE_HAS_EXPIRE_ONLY | FUSE_DIRECT_IO_ALLOW_MMAP;
+ FUSE_HAS_EXPIRE_ONLY | FUSE_DIRECT_IO_ALLOW_MMAP |
+ FUSE_HAS_RESEND;
#ifdef CONFIG_FUSE_DAX
if (fm->fc->dax)
flags |= FUSE_MAP_ALIGNMENT;
@@ -410,6 +410,8 @@ struct fuse_file_lock {
* symlink and mknod (single group that matches parent)
* FUSE_HAS_EXPIRE_ONLY: kernel supports expiry-only entry invalidation
* FUSE_DIRECT_IO_ALLOW_MMAP: allow shared mmap in FOPEN_DIRECT_IO mode.
+ * FUSE_HAS_RESEND: kernel supports resending pending requests, and the high bit
+ * of the request ID indicates resend requests
*/
#define FUSE_ASYNC_READ (1 << 0)
#define FUSE_POSIX_LOCKS (1 << 1)
@@ -449,6 +451,7 @@ struct fuse_file_lock {
#define FUSE_CREATE_SUPP_GROUP (1ULL << 34)
#define FUSE_HAS_EXPIRE_ONLY (1ULL << 35)
#define FUSE_DIRECT_IO_ALLOW_MMAP (1ULL << 36)
+#define FUSE_HAS_RESEND (1ULL << 37)
/* Obsolete alias for FUSE_DIRECT_IO_ALLOW_MMAP */
#define FUSE_DIRECT_IO_RELAX FUSE_DIRECT_IO_ALLOW_MMAP
@@ -961,6 +964,14 @@ struct fuse_fallocate_in {
uint32_t padding;
};
+/**
+ * FUSE request unique ID flag
+ *
+ * Indicates whether this is a resend request. The receiver should handle this
+ * request accordingly.
+ */
+#define FUSE_UNIQUE_RESEND (1ULL << 63)
+
struct fuse_in_header {
uint32_t len;
uint32_t opcode;
Some FUSE daemons want to know if the received request is a resend request. The high bit of the fuse request ID is utilized for indicating this, enabling the receiver to perform appropriate handling. The init flag "FUSE_HAS_RESEND" is added to indicate this feature. Signed-off-by: Zhao Chen <winters.zc@antgroup.com> --- fs/fuse/dev.c | 5 ++++- fs/fuse/inode.c | 3 ++- include/uapi/linux/fuse.h | 11 +++++++++++ 3 files changed, 17 insertions(+), 2 deletions(-)