From e65395521bae162b72f038f02ccbe5686f7bf88c Mon Sep 17 00:00:00 2001 From: Bernd Schubert Date: Fri, 7 Mar 2025 22:43:50 +0100 Subject: fuse_session_receive_buf: Fix the pipe buf size This fixes dynamic buffer allocation in commit 0e0f43b79b9b ("Reallocate fuse_session buffer...") I noticed that when I increased the default fuse buf size as possible in recent kernels. Signed-off-by: Bernd Schubert --- lib/fuse_i.h | 4 ++-- lib/fuse_lowlevel.c | 12 +++++++++++- 2 files changed, 13 insertions(+), 3 deletions(-) diff --git a/lib/fuse_i.h b/lib/fuse_i.h index 6fbfc2d..ee0d298 100644 --- a/lib/fuse_i.h +++ b/lib/fuse_i.h @@ -75,14 +75,14 @@ struct fuse_session { int broken_splice_nonblock; uint64_t notify_ctr; struct fuse_notify_req notify_list; - size_t bufsize; + _Atomic size_t bufsize; int error; /* This is useful if any kind of ABI incompatibility is found at * a later version, to 'fix' it at run time. */ struct libfuse_version version; - bool buf_reallocable; + _Atomic bool buf_reallocable; }; struct fuse_chan { diff --git a/lib/fuse_lowlevel.c b/lib/fuse_lowlevel.c index c22b4a2..7df3c7a 100644 --- a/lib/fuse_lowlevel.c +++ b/lib/fuse_lowlevel.c @@ -3026,11 +3026,14 @@ static int _fuse_session_receive_buf(struct fuse_session *se, { int err; ssize_t res; - size_t bufsize = se->bufsize; + size_t bufsize; #ifdef HAVE_SPLICE struct fuse_ll_pipe *llp; struct fuse_buf tmpbuf; +pipe_retry: + bufsize = se->bufsize; + if (se->conn.proto_minor < 14 || !(se->conn.want_ext & FUSE_CAP_SPLICE_READ)) goto fallback; @@ -3075,6 +3078,13 @@ static int _fuse_session_receive_buf(struct fuse_session *se, fuse_session_exit(se); return 0; } + + /* FUSE_INIT might have increased the required bufsize */ + if (err == EINVAL && bufsize < se->bufsize) { + fuse_ll_clear_pipe(se); + goto pipe_retry; + } + if (err != EINTR && err != EAGAIN) perror("fuse: splice from device"); return -err; -- cgit v1.2.3