vfs: Remove aio_linux

Triggered by https://bugzilla.samba.org/show_bug.cgi?id=13128 I think
this module should go. Once Linux aio will do what Samba needs, this
might be worth another look.

What we should instead do soon is support Linux preadv2 and the
RWF_NOWAIT flag to avoid the thread context switch whenever possible.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>

3 files changed, 0 insertions, 380 deletions

diff --git a/source3/modules/vfs_aio_linux.c b/source3/modules/vfs_aio_linux.c
deleted file mode 100644
index e89c2905bad..00000000000
--- a/source3/modules/vfs_aio_linux.c
+++ /dev/null
@@ -1,346 +0,0 @@
-/*
- * Simulate Posix AIO using Linux kernel AIO.
- *
- * Copyright (C) Jeremy Allison 2012
- * Copyright (C) Volker Lendecke 2012
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include "includes.h"
-#include "system/filesys.h"
-#include "smbd/smbd.h"
-#include "smbd/globals.h"
-#include "lib/util/tevent_unix.h"
-#include "lib/util/sys_rw.h"
-#include <sys/eventfd.h>
-#include <libaio.h>
-#include "smbprofile.h"
-
-static int event_fd = -1;
-static io_context_t io_ctx;
-static struct tevent_fd *aio_read_event;
-static bool used;
-static unsigned num_busy;
-
-static void aio_linux_done(struct tevent_context *event_ctx,
-			   struct tevent_fd *event,
-			   uint16_t flags, void *private_data);
-
-/************************************************************************
- Housekeeping. Cleanup if no activity for 30 seconds.
-***********************************************************************/
-
-static void aio_linux_housekeeping(struct tevent_context *event_ctx,
-                                        struct tevent_timer *te,
-                                        struct timeval now,
-                                        void *private_data)
-{
-	/* Remove this timed event handler. */
-	TALLOC_FREE(te);
-
-	if ((num_busy != 0) || used) {
-		used = false;
-
-		/* Still busy. Look again in 30 seconds. */
-		(void)tevent_add_timer(event_ctx,
-					NULL,
-					timeval_current_ofs(30, 0),
-					aio_linux_housekeeping,
-					NULL);
-		return;
-	}
-
-	/* No activity for 30 seconds. Close out kernel resources. */
-	io_queue_release(io_ctx);
-	memset(&io_ctx, '\0', sizeof(io_ctx));
-
-	if (event_fd != -1) {
-		close(event_fd);
-		event_fd = -1;
-	}
-
-	TALLOC_FREE(aio_read_event);
-}
-
-/************************************************************************
- Ensure event fd and aio context are initialized.
-***********************************************************************/
-
-static bool init_aio_linux(struct vfs_handle_struct *handle)
-{
-	struct tevent_timer *te = NULL;
-
-	if (event_fd != -1) {
-		/* Already initialized. */
-		return true;
-	}
-
-	/* Schedule a shutdown event for 30 seconds from now. */
-	te = tevent_add_timer(handle->conn->sconn->ev_ctx,
-				NULL,
-				timeval_current_ofs(30, 0),
-				aio_linux_housekeeping,
-				NULL);
-
-	if (te == NULL) {
-		goto fail;
-	}
-
-	event_fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
-	if (event_fd == -1) {
-		goto fail;
-	}
-
-	aio_read_event = tevent_add_fd(server_event_context(),
-				NULL,
-				event_fd,
-				TEVENT_FD_READ,
-				aio_linux_done,
-				NULL);
-	if (aio_read_event == NULL) {
-		goto fail;
-	}
-
-	if (io_queue_init(lp_aio_max_threads(), &io_ctx)) {
-		goto fail;
-	}
-
-	DEBUG(10,("init_aio_linux: initialized with up to %d events\n",
-		  (int)lp_aio_max_threads()));
-
-	return true;
-
-  fail:
-
-	DEBUG(10,("init_aio_linux: initialization failed\n"));
-
-	TALLOC_FREE(te);
-	TALLOC_FREE(aio_read_event);
-	if (event_fd != -1) {
-		close(event_fd);
-		event_fd = -1;
-	}
-	memset(&io_ctx, '\0', sizeof(io_ctx));
-	return false;
-}
-
-struct aio_linux_state {
-	struct iocb event_iocb;
-	ssize_t ret;
-	struct vfs_aio_state vfs_aio_state;
-	struct timespec start;
-};
-
-static struct tevent_req *aio_linux_pread_send(
-	struct vfs_handle_struct *handle, TALLOC_CTX *mem_ctx,
-	struct tevent_context *ev, struct files_struct *fsp,
-	void *data, size_t n, off_t offset)
-{
-	struct tevent_req *req;
-	struct aio_linux_state *state;
-	struct iocb *piocb;
-	int ret;
-
-	req = tevent_req_create(mem_ctx, &state, struct aio_linux_state);
-	if (req == NULL) {
-		return NULL;
-	}
-	if (!init_aio_linux(handle)) {
-		tevent_req_error(req, EIO);
-		return tevent_req_post(req, ev);
-	}
-
-	io_prep_pread(&state->event_iocb, fsp->fh->fd, data, n, offset);
-	io_set_eventfd(&state->event_iocb, event_fd);
-	state->event_iocb.data = req;
-
-	piocb = &state->event_iocb;
-
-	PROFILE_TIMESTAMP(&state->start);
-	ret = io_submit(io_ctx, 1, &piocb);
-	if (ret < 0) {
-		tevent_req_error(req, -ret);
-		return tevent_req_post(req, ev);
-	}
-	num_busy += 1;
-	used = true;
-	return req;
-}
-
-static struct tevent_req *aio_linux_pwrite_send(
-	struct vfs_handle_struct *handle, TALLOC_CTX *mem_ctx,
-	struct tevent_context *ev, struct files_struct *fsp,
-	const void *data, size_t n, off_t offset)
-{
-	struct tevent_req *req;
-	struct aio_linux_state *state;
-	struct iocb *piocb;
-	int ret;
-
-	req = tevent_req_create(mem_ctx, &state, struct aio_linux_state);
-	if (req == NULL) {
-		return NULL;
-	}
-	if (!init_aio_linux(handle)) {
-		tevent_req_error(req, EIO);
-		return tevent_req_post(req, ev);
-	}
-
-	io_prep_pwrite(&state->event_iocb, fsp->fh->fd, discard_const(data),
-		       n, offset);
-	io_set_eventfd(&state->event_iocb, event_fd);
-	state->event_iocb.data = req;
-
-	piocb = &state->event_iocb;
-
-	PROFILE_TIMESTAMP(&state->start);
-	ret = io_submit(io_ctx, 1, &piocb);
-	if (ret < 0) {
-		tevent_req_error(req, -ret);
-		return tevent_req_post(req, ev);
-	}
-	num_busy += 1;
-	used = true;
-	return req;
-}
-
-static struct tevent_req *aio_linux_fsync_send(
-	struct vfs_handle_struct *handle, TALLOC_CTX *mem_ctx,
-	struct tevent_context *ev, struct files_struct *fsp)
-{
-	struct tevent_req *req;
-	struct aio_linux_state *state;
-	struct iocb *piocb;
-	int ret;
-
-	req = tevent_req_create(mem_ctx, &state, struct aio_linux_state);
-	if (req == NULL) {
-		return NULL;
-	}
-	if (!init_aio_linux(handle)) {
-		tevent_req_error(req, EIO);
-		return tevent_req_post(req, ev);
-	}
-
-	io_prep_fsync(&state->event_iocb, fsp->fh->fd);
-	io_set_eventfd(&state->event_iocb, event_fd);
-	state->event_iocb.data = req;
-
-	piocb = &state->event_iocb;
-
-	PROFILE_TIMESTAMP(&state->start);
-	ret = io_submit(io_ctx, 1, &piocb);
-	if (ret < 0) {
-		tevent_req_error(req, -ret);
-		return tevent_req_post(req, ev);
-	}
-	num_busy += 1;
-	used = true;
-	return req;
-}
-
-static void aio_linux_done(struct tevent_context *event_ctx,
-			   struct tevent_fd *event,
-			   uint16_t flags, void *private_data)
-{
-	uint64_t num_events = 0;
-	struct timespec end;
-
-	DEBUG(10, ("aio_linux_done called with flags=%d\n",
-		   (int)flags));
-
-	PROFILE_TIMESTAMP(&end);
-
-	/* Read the number of events available. */
-	if (sys_read(event_fd, &num_events, sizeof(num_events)) !=
-			sizeof(num_events)) {
-		smb_panic("aio_linux_handle_completion: invalid read");
-	}
-
-	while (num_events > 0) {
-		struct timespec ts = { 0, };
-		struct io_event finished;
-		struct tevent_req *req;
-		struct aio_linux_state *state;
-		int ret;
-
-		ret = io_getevents(io_ctx, 1, 1, &finished, &ts);
-		if (ret < 0) {
-			DEBUG(1, ("aio_linux_done: io_getevents returned %s\n",
-				  strerror(-ret)));
-			return;
-		}
-		if (ret == 0) {
-			DEBUG(10, ("aio_linux_done: io_getvents returned "
-				   "0\n"));
-			continue;
-		}
-
-		num_busy -= 1;
-
-		req = talloc_get_type_abort(finished.data,
-					    struct tevent_req);
-		state = tevent_req_data(req, struct aio_linux_state);
-
-		if (finished.res < 0) {
-			state->ret = -1;
-			state->vfs_aio_state.error = -finished.res;
-		} else {
-			state->ret = finished.res;
-		}
-		state->vfs_aio_state.duration = nsec_time_diff(&end, &state->start);
-		tevent_req_done(req);
-		num_events -= 1;
-	}
-}
-
-static ssize_t aio_linux_recv(struct tevent_req *req,
-			      struct vfs_aio_state *vfs_aio_state)
-{
-	struct aio_linux_state *state = tevent_req_data(
-		req, struct aio_linux_state);
-
-	if (tevent_req_is_unix_error(req, &vfs_aio_state->error)) {
-		return -1;
-	}
-	*vfs_aio_state = state->vfs_aio_state;
-	return state->ret;
-}
-
-static int aio_linux_int_recv(struct tevent_req *req,
-			      struct vfs_aio_state *vfs_aio_state)
-{
-	/*
-	 * Use implicit conversion ssize_t->int
-	 */
-	return aio_linux_recv(req, vfs_aio_state);
-}
-
-static struct vfs_fn_pointers vfs_aio_linux_fns = {
-	.pread_send_fn = aio_linux_pread_send,
-	.pread_recv_fn = aio_linux_recv,
-	.pwrite_send_fn = aio_linux_pwrite_send,
-	.pwrite_recv_fn = aio_linux_recv,
-	.fsync_send_fn = aio_linux_fsync_send,
-	.fsync_recv_fn = aio_linux_int_recv,
-};
-
-static_decl_vfs;
-NTSTATUS vfs_aio_linux_init(TALLOC_CTX *ctx)
-{
-	return smb_register_vfs(SMB_VFS_INTERFACE_VERSION,
-				"aio_linux", &vfs_aio_linux_fns);
-}
diff --git a/source3/modules/wscript_build b/source3/modules/wscript_build
index ab9be384189..4e4fdb98a1d 100644
--- a/source3/modules/wscript_build
+++ b/source3/modules/wscript_build
@@ -357,14 +357,6 @@ bld.SAMBA3_MODULE('vfs_aio_pthread',
                  internal_module=bld.SAMBA3_IS_STATIC_MODULE('vfs_aio_pthread'),
                  enabled=bld.SAMBA3_IS_ENABLED_MODULE('vfs_aio_pthread'))
 
-bld.SAMBA3_MODULE('vfs_aio_linux',
-                 subsystem='vfs',
-                 source='vfs_aio_linux.c',
-                 deps='samba-util aio',
-                 init_function='',
-                 internal_module=bld.SAMBA3_IS_STATIC_MODULE('vfs_aio_linux'),
-                 enabled=bld.SAMBA3_IS_ENABLED_MODULE('vfs_aio_linux'))
-
 bld.SAMBA3_MODULE('vfs_preopen',
                  subsystem='vfs',
                  source='vfs_preopen.c',
diff --git a/source3/wscript b/source3/wscript
index e311f5f6efe..d45a7d9ec60 100644
--- a/source3/wscript
+++ b/source3/wscript
@@ -551,29 +551,6 @@ return acl_get_perm_np(permset_d, perm);
                 msg='Checking for openat',
                 headers='fcntl.h')
 
-    if host_os.rfind('linux') > -1:
-        conf.CHECK_FUNCS_IN('io_submit', 'aio')
-        conf.CHECK_CODE('''
-struct io_event ioev;
-struct iocb *ioc;
-io_context_t ctx;
-struct timespec ts;
-int fd;
-char *buf;
-fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
-io_queue_init(128,&ctx);
-io_prep_pwrite(ioc, 1, buf, 1, 0);
-io_prep_pread(ioc, 1, buf, 1, 0);
-io_set_eventfd(ioc, fd);
-io_set_callback(ioc, (io_callback_t)(0));
-io_submit(ctx, 1, &ioc);
-io_getevents(ctx, 1, 1, &ioev, &ts);
-''',
-            'HAVE_LINUX_KERNEL_AIO',
-            msg='Checking for linux kernel asynchronous io support',
-            headers='unistd.h stdlib.h sys/types.h fcntl.h sys/eventfd.h libaio.h',
-            lib='aio')
-
     conf.CHECK_CODE('''
 struct msghdr msg;
 union {
@@ -1717,9 +1694,6 @@ main() {
     if Options.options.with_pthreadpool:
         default_shared_modules.extend(TO_LIST('vfs_aio_pthread'))
 
-    if conf.CONFIG_SET('HAVE_LINUX_KERNEL_AIO'):
-        default_shared_modules.extend(TO_LIST('vfs_aio_linux'))
-
     if conf.CONFIG_SET('HAVE_LDAP'):
         default_static_modules.extend(TO_LIST('pdb_ldapsam idmap_ldap'))