From: Ralph Boehme <slow@samba.org>
Date: Sun, 24 Nov 2024 08:27:36 +0000 (+0100)
Subject: vfs_io_uring: implement POSIX append-IO
X-Git-Tag: tdb-1.4.13~219
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=442bbee9bc106f75c066cca7cdc7ef4ebd55921a;p=thirdparty%2Fsamba.git

vfs_io_uring: implement POSIX append-IO

Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
---

diff --git a/source3/modules/vfs_io_uring.c b/source3/modules/vfs_io_uring.c
index b33c09a6ef8..20eb80477db 100644
--- a/source3/modules/vfs_io_uring.c
+++ b/source3/modules/vfs_io_uring.c
@@ -416,6 +416,22 @@ static void vfs_io_uring_fd_handler(struct tevent_context *ev,
 	vfs_io_uring_queue_run(config);
 }
 
+static int vfs_io_uring_openat(struct vfs_handle_struct *handle,
+			       const struct files_struct *dirfsp,
+			       const struct smb_filename *smb_fname,
+			       struct files_struct *fsp,
+			       const struct vfs_open_how *how)
+{
+#ifndef HAVE_IO_URING_PREP_WRITEV2
+	if (fsp->fsp_flags.posix_append) {
+		DBG_ERR("POSIX append-IO not supported without writev2 support");
+		errno = EINVAL;
+		return -1;
+	}
+#endif
+	return SMB_VFS_NEXT_OPENAT(handle, dirfsp, smb_fname, fsp, how);
+}
+
 struct vfs_io_uring_pread_state {
 	struct files_struct *fsp;
 	off_t offset;
@@ -606,6 +622,7 @@ static struct tevent_req *vfs_io_uring_pwrite_send(struct vfs_handle_struct *han
 	SMBPROFILE_BYTES_ASYNC_SET_IDLE(state->ur.profile_bytes);
 
 	ok = sys_valid_io_range(offset, n);
+	ok |= offset == VFS_PWRITE_APPEND_OFFSET;
 	if (!ok) {
 		tevent_req_error(req, EINVAL);
 		return tevent_req_post(req, ev);
@@ -627,10 +644,24 @@ static struct tevent_req *vfs_io_uring_pwrite_send(struct vfs_handle_struct *han
 
 static void vfs_io_uring_pwrite_submit(struct vfs_io_uring_pwrite_state *state)
 {
-	io_uring_prep_writev(&state->ur.sqe,
-			     fsp_get_io_fd(state->fsp),
-			     &state->iov, 1,
-			     state->offset);
+	if (!state->fsp->fsp_flags.posix_append) {
+		io_uring_prep_writev(&state->ur.sqe,
+				     fsp_get_io_fd(state->fsp),
+				     &state->iov, 1,
+				     state->offset);
+	}
+	else {
+#ifdef HAVE_IO_URING_PREP_WRITEV2
+		io_uring_prep_writev2(&state->ur.sqe,
+				      fsp_get_io_fd(state->fsp),
+				      &state->iov, 1,
+				      -1,
+				      RWF_APPEND);
+#else
+		/* This should have been caught by vfs_io_uring_openat() */
+		smb_panic("Unexpected POSIX append-IO");
+#endif
+	}
 	vfs_io_uring_request_submit(&state->ur);
 }
 
@@ -806,6 +837,7 @@ static int vfs_io_uring_fsync_recv(struct tevent_req *req,
 
 static struct vfs_fn_pointers vfs_io_uring_fns = {
 	.connect_fn = vfs_io_uring_connect,
+	.openat_fn = vfs_io_uring_openat,
 	.pread_send_fn = vfs_io_uring_pread_send,
 	.pread_recv_fn = vfs_io_uring_pread_recv,
 	.pwrite_send_fn = vfs_io_uring_pwrite_send,
diff --git a/source3/wscript b/source3/wscript
index f746a67b800..26327cba32f 100644
--- a/source3/wscript
+++ b/source3/wscript
@@ -1680,7 +1680,7 @@ int main(void) {
                       msg='Checking for liburing package', uselib_store="URING"):
         if (conf.CHECK_HEADERS('liburing.h', lib='uring')
                                       and conf.CHECK_LIB('uring', shlib=True)):
-            conf.CHECK_FUNCS_IN('io_uring_ring_dontfork', 'uring',
+            conf.CHECK_FUNCS_IN('io_uring_ring_dontfork io_uring_prep_writev2', 'uring',
                                 headers='liburing.h')
             # There are a few distributions, which
             # don't seem to have linux/openat2.h available