From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
Let fuse_session_process_buf_int take a fuse_bufvec * instead of a
fuse_buf; and then through to do_write_buf - where in the best
case it can pass that stragiht through to op.write_buf without copying
(other than ksipping a header).
Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
---
contrib/virtiofsd/fuse_i.h | 2 +-
contrib/virtiofsd/fuse_lowlevel.c | 67 +++++++++++++++++++------------
contrib/virtiofsd/fuse_virtio.c | 3 +-
3 files changed, 45 insertions(+), 27 deletions(-)
diff --git a/contrib/virtiofsd/fuse_i.h b/contrib/virtiofsd/fuse_i.h
index 4b718f1aec..06f3d88a44 100644
--- a/contrib/virtiofsd/fuse_i.h
+++ b/contrib/virtiofsd/fuse_i.h
@@ -119,7 +119,7 @@ int fuse_send_reply_iov_nofree(fuse_req_t req, int error,
struct iovec *iov,
void fuse_free_req(fuse_req_t req);
void fuse_session_process_buf_int(struct fuse_session *se,
- const struct fuse_buf *buf, struct fuse_chan
*ch);
+ struct fuse_bufvec *bufv, struct fuse_chan
*ch);
#define FUSE_MAX_MAX_PAGES 256
diff --git a/contrib/virtiofsd/fuse_lowlevel.c
b/contrib/virtiofsd/fuse_lowlevel.c
index dd046ecf07..2bd2ba00b9 100644
--- a/contrib/virtiofsd/fuse_lowlevel.c
+++ b/contrib/virtiofsd/fuse_lowlevel.c
@@ -1007,11 +1007,12 @@ static void do_write(fuse_req_t req, fuse_ino_t nodeid,
const void *inarg)
}
static void do_write_buf(fuse_req_t req, fuse_ino_t nodeid, const void *inarg,
- const struct fuse_buf *ibuf)
+ struct fuse_bufvec *ibufv)
{
struct fuse_session *se = req->se;
- struct fuse_bufvec bufv = {
- .buf[0] = *ibuf,
+ struct fuse_bufvec *pbufv = ibufv;
+ struct fuse_bufvec tmpbufv = {
+ .buf[0] = ibufv->buf[0],
.count = 1,
};
struct fuse_write_in *arg = (struct fuse_write_in *) inarg;
@@ -1021,28 +1022,35 @@ static void do_write_buf(fuse_req_t req, fuse_ino_t
nodeid, const void *inarg,
fi.fh = arg->fh;
fi.writepage = arg->write_flags & FUSE_WRITE_CACHE;
- if (se->conn.proto_minor < 9) {
- bufv.buf[0].mem = ((char *) arg) + FUSE_COMPAT_WRITE_IN_SIZE;
- bufv.buf[0].size -= sizeof(struct fuse_in_header) +
- FUSE_COMPAT_WRITE_IN_SIZE;
- assert(!(bufv.buf[0].flags & FUSE_BUF_IS_FD));
- } else {
- fi.lock_owner = arg->lock_owner;
- fi.flags = arg->flags;
- if (!(bufv.buf[0].flags & FUSE_BUF_IS_FD))
- bufv.buf[0].mem = PARAM(arg);
+ if (ibufv->count == 1) {
+ if (se->conn.proto_minor < 9) {
+ tmpbufv.buf[0].mem = ((char *) arg) +
FUSE_COMPAT_WRITE_IN_SIZE;
+ tmpbufv.buf[0].size -= sizeof(struct fuse_in_header) +
+ FUSE_COMPAT_WRITE_IN_SIZE;
+ assert(!(tmpbufv.buf[0].flags & FUSE_BUF_IS_FD));
+ } else {
+ fi.lock_owner = arg->lock_owner;
+ fi.flags = arg->flags;
+ if (!(tmpbufv.buf[0].flags & FUSE_BUF_IS_FD))
+ tmpbufv.buf[0].mem = PARAM(arg);
- bufv.buf[0].size -= sizeof(struct fuse_in_header) +
- sizeof(struct fuse_write_in);
- }
- if (bufv.buf[0].size < arg->size) {
- fuse_log(FUSE_LOG_ERR, "fuse: do_write_buf: buffer size too
small\n");
- fuse_reply_err(req, EIO);
- return;
+ tmpbufv.buf[0].size -= sizeof(struct fuse_in_header) +
+ sizeof(struct fuse_write_in);
+ }
+ if (tmpbufv.buf[0].size < arg->size) {
+ fuse_log(FUSE_LOG_ERR, "fuse: do_write_buf: buffer size
too small\n");
+ fuse_reply_err(req, EIO);
+ return;
+ }
+ tmpbufv.buf[0].size = arg->size;
+ pbufv = &tmpbufv;
+ } else {
+ // Input bufv contains the headers in the first element
+ // and the data in the rest, we need to skip that first element
+ ibufv->buf[0].size = 0;
}
- bufv.buf[0].size = arg->size;
- se->op.write_buf(req, nodeid, &bufv, arg->offset, &fi);
+ se->op.write_buf(req, nodeid, pbufv, arg->offset, &fi);
}
static void do_flush(fuse_req_t req, fuse_ino_t nodeid, const void *inarg)
@@ -1979,12 +1987,21 @@ static const char *opname(enum fuse_opcode opcode)
void fuse_session_process_buf(struct fuse_session *se,
const struct fuse_buf *buf)
{
- fuse_session_process_buf_int(se, buf, NULL);
+ struct fuse_bufvec bufv = { .buf[0] = *buf, .count = 1 };
+ fuse_session_process_buf_int(se, &bufv, NULL);
}
+// Restriction:
+// bufv is normally a single entry buffer, except for a write
+// where (if it's in memory) then the bufv may be multiple entries,
+// where the first entry contains all headers and subsequent entries
+// contain data
+// bufv shall not use any offsets etc to make the data anything
+// other than contiguous starting from 0.
void fuse_session_process_buf_int(struct fuse_session *se,
- const struct fuse_buf *buf, struct fuse_chan
*ch)
+ struct fuse_bufvec *bufv, struct fuse_chan
*ch)
{
+ const struct fuse_buf *buf = bufv->buf;
struct fuse_in_header *in;
const void *inarg;
struct fuse_req *req;
@@ -2057,7 +2074,7 @@ void fuse_session_process_buf_int(struct fuse_session *se,
inarg = (void *) &in[1];
if (in->opcode == FUSE_WRITE && se->op.write_buf)
- do_write_buf(req, in->nodeid, inarg, buf);
+ do_write_buf(req, in->nodeid, inarg, bufv);
else
fuse_ll_ops[in->opcode].func(req, in->nodeid, inarg);
diff --git a/contrib/virtiofsd/fuse_virtio.c b/contrib/virtiofsd/fuse_virtio.c
index 1f09fad93d..68036e2171 100644
--- a/contrib/virtiofsd/fuse_virtio.c
+++ b/contrib/virtiofsd/fuse_virtio.c
@@ -499,7 +499,8 @@ static void *fv_queue_thread(void *opaque)
/* TODO! Endianness of header */
/* TODO: Add checks for fuse_session_exited */
- fuse_session_process_buf_int(se, &fbuf, &ch);
+ struct fuse_bufvec bufv = { .buf[0] = fbuf, .count = 1 };
+ fuse_session_process_buf_int(se, &bufv, &ch);
if (!qi->reply_sent) {
fuse_log(FUSE_LOG_DEBUG, "%s: elem %d no reply sent\n",
--
2.23.0
