xen: remove unnecessary code from dataplane/xen-block.c

Not all of the code duplicated from xen_disk.c is required as the basis for
the new dataplane implementation so this patch removes extraneous code,
along with the legacy #includes and calls to the legacy xen_pv_printf()
function. Error messages are changed to be reported using error_report().

NOTE: The code is still not yet built. Further transformations will be
      required to make it correctly interface to the new XenBus/XenDevice
      framework. They will be delivered in a subsequent patch.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
This commit is contained in:
Paul Durrant 2019-01-08 14:48:54 +00:00 committed by Anthony PERARD
parent 4ea7d1a7f1
commit ca07280075

View File

@ -1,45 +1,23 @@
/*
* xen paravirt block device backend
* Copyright (c) 2018 Citrix Systems Inc.
* (c) Gerd Hoffmann <kraxel@redhat.com>
*
* (c) Gerd Hoffmann <kraxel@redhat.com>
* 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; under version 2 of the License.
*
* 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; under version 2 of the License.
* 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.
*
* 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, see <http://www.gnu.org/licenses/>.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, see <http://www.gnu.org/licenses/>.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu/osdep.h"
#include "qemu/units.h"
#include <sys/ioctl.h>
#include <sys/uio.h>
#include "hw/hw.h"
#include "hw/xen/xen_backend.h"
#include "xen_blkif.h"
#include "sysemu/blockdev.h"
#include "sysemu/iothread.h"
#include "sysemu/block-backend.h"
#include "qapi/error.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qstring.h"
#include "trace.h"
/* ------------------------------------------------------------- */
#define BLOCK_SIZE 512
#define IOCB_COUNT (BLKIF_MAX_SEGMENTS_PER_REQUEST + 2)
struct ioreq {
blkif_request_t req;
int16_t status;
@ -101,8 +79,6 @@ struct XenBlkDev {
AioContext *ctx;
};
/* ------------------------------------------------------------- */
static void ioreq_reset(struct ioreq *ioreq)
{
memset(&ioreq->req, 0, sizeof(ioreq->req));
@ -183,11 +159,6 @@ static int ioreq_parse(struct ioreq *ioreq)
size_t len;
int i;
xen_pv_printf(
xendev, 3,
"op %d, nr %d, handle %d, id %" PRId64 ", sector %" PRId64 "\n",
ioreq->req.operation, ioreq->req.nr_segments,
ioreq->req.handle, ioreq->req.id, ioreq->req.sector_number);
switch (ioreq->req.operation) {
case BLKIF_OP_READ:
break;
@ -202,28 +173,27 @@ static int ioreq_parse(struct ioreq *ioreq)
case BLKIF_OP_DISCARD:
return 0;
default:
xen_pv_printf(xendev, 0, "error: unknown operation (%d)\n",
ioreq->req.operation);
error_report("error: unknown operation (%d)", ioreq->req.operation);
goto err;
};
if (ioreq->req.operation != BLKIF_OP_READ && blkdev->mode[0] != 'w') {
xen_pv_printf(xendev, 0, "error: write req for ro device\n");
error_report("error: write req for ro device");
goto err;
}
ioreq->start = ioreq->req.sector_number * blkdev->file_blk;
for (i = 0; i < ioreq->req.nr_segments; i++) {
if (i == BLKIF_MAX_SEGMENTS_PER_REQUEST) {
xen_pv_printf(xendev, 0, "error: nr_segments too big\n");
error_report("error: nr_segments too big");
goto err;
}
if (ioreq->req.seg[i].first_sect > ioreq->req.seg[i].last_sect) {
xen_pv_printf(xendev, 0, "error: first > last sector\n");
error_report("error: first > last sector");
goto err;
}
if (ioreq->req.seg[i].last_sect * BLOCK_SIZE >= XC_PAGE_SIZE) {
xen_pv_printf(xendev, 0, "error: page crossing\n");
error_report("error: page crossing");
goto err;
}
@ -232,7 +202,7 @@ static int ioreq_parse(struct ioreq *ioreq)
ioreq->size += len;
}
if (ioreq->start + ioreq->size > blkdev->file_size) {
xen_pv_printf(xendev, 0, "error: access beyond end of file\n");
error_report("error: access beyond end of file");
goto err;
}
return 0;
@ -278,8 +248,7 @@ static int ioreq_grant_copy(struct ioreq *ioreq)
rc = xen_be_copy_grant_refs(xendev, to_domain, segs, count);
if (rc) {
xen_pv_printf(xendev, 0,
"failed to copy data %d\n", rc);
error_report("failed to copy data %d", rc);
ioreq->aio_errors++;
return -1;
}
@ -298,8 +267,9 @@ static void qemu_aio_complete(void *opaque, int ret)
aio_context_acquire(blkdev->ctx);
if (ret != 0) {
xen_pv_printf(xendev, 0, "%s I/O error\n",
ioreq->req.operation == BLKIF_OP_READ ? "read" : "write");
error_report("%s I/O error",
ioreq->req.operation == BLKIF_OP_READ ?
"read" : "write");
ioreq->aio_errors++;
}
@ -605,8 +575,6 @@ static void blk_handle_requests(struct XenBlkDev *blkdev)
}
}
/* ------------------------------------------------------------- */
static void blk_bh(void *opaque)
{
struct XenBlkDev *blkdev = opaque;
@ -634,346 +602,6 @@ static void blk_alloc(struct XenLegacyDevice *xendev)
blkdev->bh = aio_bh_new(blkdev->ctx, blk_bh, blkdev);
}
static void blk_parse_discard(struct XenBlkDev *blkdev)
{
struct XenLegacyDevice *xendev = &blkdev->xendev;
int enable;
blkdev->feature_discard = true;
if (xenstore_read_be_int(xendev, "discard-enable", &enable) == 0) {
blkdev->feature_discard = !!enable;
}
if (blkdev->feature_discard) {
xenstore_write_be_int(xendev, "feature-discard", 1);
}
}
static int blk_init(struct XenLegacyDevice *xendev)
{
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
int info = 0;
char *directiosafe = NULL;
trace_xen_disk_init(xendev->name);
/* read xenstore entries */
if (blkdev->params == NULL) {
char *h = NULL;
blkdev->params = xenstore_read_be_str(xendev, "params");
if (blkdev->params != NULL) {
h = strchr(blkdev->params, ':');
}
if (h != NULL) {
blkdev->fileproto = blkdev->params;
blkdev->filename = h + 1;
*h = 0;
} else {
blkdev->fileproto = "<unset>";
blkdev->filename = blkdev->params;
}
}
if (!strcmp("aio", blkdev->fileproto)) {
blkdev->fileproto = "raw";
}
if (!strcmp("vhd", blkdev->fileproto)) {
blkdev->fileproto = "vpc";
}
if (blkdev->mode == NULL) {
blkdev->mode = xenstore_read_be_str(xendev, "mode");
}
if (blkdev->type == NULL) {
blkdev->type = xenstore_read_be_str(xendev, "type");
}
if (blkdev->dev == NULL) {
blkdev->dev = xenstore_read_be_str(xendev, "dev");
}
if (blkdev->devtype == NULL) {
blkdev->devtype = xenstore_read_be_str(xendev, "device-type");
}
directiosafe = xenstore_read_be_str(xendev, "direct-io-safe");
blkdev->directiosafe = (directiosafe && atoi(directiosafe));
/* do we have all we need? */
if (blkdev->params == NULL ||
blkdev->mode == NULL ||
blkdev->type == NULL ||
blkdev->dev == NULL) {
goto out_error;
}
/* read-only ? */
if (strcmp(blkdev->mode, "w")) {
info |= VDISK_READONLY;
}
/* cdrom ? */
if (blkdev->devtype && !strcmp(blkdev->devtype, "cdrom")) {
info |= VDISK_CDROM;
}
blkdev->file_blk = BLOCK_SIZE;
/* fill info
* blk_connect supplies sector-size and sectors
*/
xenstore_write_be_int(xendev, "feature-flush-cache", 1);
xenstore_write_be_int(xendev, "info", info);
xenstore_write_be_int(xendev, "max-ring-page-order",
MAX_RING_PAGE_ORDER);
blk_parse_discard(blkdev);
g_free(directiosafe);
return 0;
out_error:
g_free(blkdev->params);
blkdev->params = NULL;
g_free(blkdev->mode);
blkdev->mode = NULL;
g_free(blkdev->type);
blkdev->type = NULL;
g_free(blkdev->dev);
blkdev->dev = NULL;
g_free(blkdev->devtype);
blkdev->devtype = NULL;
g_free(directiosafe);
blkdev->directiosafe = false;
return -1;
}
static int blk_connect(struct XenLegacyDevice *xendev)
{
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
int index, qflags;
bool readonly = true;
bool writethrough = true;
int order, ring_ref;
unsigned int ring_size, max_grants;
unsigned int i;
trace_xen_disk_connect(xendev->name);
/* read-only ? */
if (blkdev->directiosafe) {
qflags = BDRV_O_NOCACHE | BDRV_O_NATIVE_AIO;
} else {
qflags = 0;
writethrough = false;
}
if (strcmp(blkdev->mode, "w") == 0) {
qflags |= BDRV_O_RDWR;
readonly = false;
}
if (blkdev->feature_discard) {
qflags |= BDRV_O_UNMAP;
}
/* init qemu block driver */
index = (xendev->dev - 202 * 256) / 16;
blkdev->dinfo = drive_get(IF_XEN, 0, index);
if (!blkdev->dinfo) {
Error *local_err = NULL;
QDict *options = NULL;
if (strcmp(blkdev->fileproto, "<unset>")) {
options = qdict_new();
qdict_put_str(options, "driver", blkdev->fileproto);
}
/* setup via xenbus -> create new block driver instance */
xen_pv_printf(xendev, 2, "create new bdrv (xenbus setup)\n");
blkdev->blk = blk_new_open(blkdev->filename, NULL, options,
qflags, &local_err);
if (!blkdev->blk) {
xen_pv_printf(xendev, 0, "error: %s\n",
error_get_pretty(local_err));
error_free(local_err);
return -1;
}
blk_set_enable_write_cache(blkdev->blk, !writethrough);
} else {
/* setup via qemu cmdline -> already setup for us */
xen_pv_printf(xendev, 2,
"get configured bdrv (cmdline setup)\n");
blkdev->blk = blk_by_legacy_dinfo(blkdev->dinfo);
if (blk_is_read_only(blkdev->blk) && !readonly) {
xen_pv_printf(xendev, 0, "Unexpected read-only drive");
blkdev->blk = NULL;
return -1;
}
/* blkdev->blk is not create by us, we get a reference
* so we can blk_unref() unconditionally */
blk_ref(blkdev->blk);
}
blk_attach_dev_legacy(blkdev->blk, blkdev);
blkdev->file_size = blk_getlength(blkdev->blk);
if (blkdev->file_size < 0) {
BlockDriverState *bs = blk_bs(blkdev->blk);
const char *drv_name = bs ? bdrv_get_format_name(bs) : NULL;
xen_pv_printf(xendev, 1, "blk_getlength: %d (%s) | drv %s\n",
(int)blkdev->file_size, strerror(-blkdev->file_size),
drv_name ?: "-");
blkdev->file_size = 0;
}
xen_pv_printf(xendev, 1, "type \"%s\", fileproto \"%s\", filename \"%s\","
" size %" PRId64 " (%" PRId64 " MB)\n",
blkdev->type, blkdev->fileproto, blkdev->filename,
blkdev->file_size, blkdev->file_size / MiB);
/* Fill in number of sector size and number of sectors */
xenstore_write_be_int(xendev, "sector-size", blkdev->file_blk);
xenstore_write_be_int64(xendev, "sectors",
blkdev->file_size / blkdev->file_blk);
if (xenstore_read_fe_int(xendev, "ring-page-order",
&order) == -1) {
blkdev->nr_ring_ref = 1;
if (xenstore_read_fe_int(xendev, "ring-ref",
&ring_ref) == -1) {
return -1;
}
blkdev->ring_ref[0] = ring_ref;
} else if (order >= 0 && order <= MAX_RING_PAGE_ORDER) {
blkdev->nr_ring_ref = 1 << order;
for (i = 0; i < blkdev->nr_ring_ref; i++) {
char *key;
key = g_strdup_printf("ring-ref%u", i);
if (!key) {
return -1;
}
if (xenstore_read_fe_int(xendev, key,
&ring_ref) == -1) {
g_free(key);
return -1;
}
blkdev->ring_ref[i] = ring_ref;
g_free(key);
}
} else {
xen_pv_printf(xendev, 0, "invalid ring-page-order: %d\n",
order);
return -1;
}
if (xenstore_read_fe_int(xendev, "event-channel",
&xendev->remote_port) == -1) {
return -1;
}
if (!xendev->protocol) {
blkdev->protocol = BLKIF_PROTOCOL_NATIVE;
} else if (strcmp(xendev->protocol, XEN_IO_PROTO_ABI_NATIVE) == 0) {
blkdev->protocol = BLKIF_PROTOCOL_NATIVE;
} else if (strcmp(xendev->protocol, XEN_IO_PROTO_ABI_X86_32) == 0) {
blkdev->protocol = BLKIF_PROTOCOL_X86_32;
} else if (strcmp(xendev->protocol, XEN_IO_PROTO_ABI_X86_64) == 0) {
blkdev->protocol = BLKIF_PROTOCOL_X86_64;
} else {
blkdev->protocol = BLKIF_PROTOCOL_NATIVE;
}
ring_size = XC_PAGE_SIZE * blkdev->nr_ring_ref;
switch (blkdev->protocol) {
case BLKIF_PROTOCOL_NATIVE:
{
blkdev->max_requests = __CONST_RING_SIZE(blkif, ring_size);
break;
}
case BLKIF_PROTOCOL_X86_32:
{
blkdev->max_requests = __CONST_RING_SIZE(blkif_x86_32, ring_size);
break;
}
case BLKIF_PROTOCOL_X86_64:
{
blkdev->max_requests = __CONST_RING_SIZE(blkif_x86_64, ring_size);
break;
}
default:
return -1;
}
/* Add on the number needed for the ring pages */
max_grants = blkdev->nr_ring_ref;
xen_be_set_max_grant_refs(xendev, max_grants);
blkdev->sring = xen_be_map_grant_refs(xendev, blkdev->ring_ref,
blkdev->nr_ring_ref,
PROT_READ | PROT_WRITE);
if (!blkdev->sring) {
return -1;
}
switch (blkdev->protocol) {
case BLKIF_PROTOCOL_NATIVE:
{
blkif_sring_t *sring_native = blkdev->sring;
BACK_RING_INIT(&blkdev->rings.native, sring_native, ring_size);
break;
}
case BLKIF_PROTOCOL_X86_32:
{
blkif_x86_32_sring_t *sring_x86_32 = blkdev->sring;
BACK_RING_INIT(&blkdev->rings.x86_32_part, sring_x86_32, ring_size);
break;
}
case BLKIF_PROTOCOL_X86_64:
{
blkif_x86_64_sring_t *sring_x86_64 = blkdev->sring;
BACK_RING_INIT(&blkdev->rings.x86_64_part, sring_x86_64, ring_size);
break;
}
}
blk_set_aio_context(blkdev->blk, blkdev->ctx);
xen_be_bind_evtchn(xendev);
xen_pv_printf(xendev, 1, "ok: proto %s, nr-ring-ref %u, "
"remote port %d, local port %d\n",
xendev->protocol, blkdev->nr_ring_ref,
xendev->remote_port, xendev->local_port);
return 0;
}
static void blk_disconnect(struct XenLegacyDevice *xendev)
{
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
trace_xen_disk_disconnect(xendev->name);
aio_context_acquire(blkdev->ctx);
if (blkdev->blk) {
blk_set_aio_context(blkdev->blk, qemu_get_aio_context());
blk_detach_dev(blkdev->blk, blkdev);
blk_unref(blkdev->blk);
blkdev->blk = NULL;
}
xen_pv_unbind_evtchn(xendev);
aio_context_release(blkdev->ctx);
if (blkdev->sring) {
xen_be_unmap_grant_refs(xendev, blkdev->sring,
blkdev->nr_ring_ref);
blkdev->sring = NULL;
}
}
static int blk_free(struct XenLegacyDevice *xendev)
{
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
@ -1006,14 +634,3 @@ static void blk_event(struct XenLegacyDevice *xendev)
qemu_bh_schedule(blkdev->bh);
}
struct XenDevOps xen_blkdev_ops = {
.flags = DEVOPS_FLAG_NEED_GNTDEV,
.size = sizeof(struct XenBlkDev),
.alloc = blk_alloc,
.init = blk_init,
.initialise = blk_connect,
.disconnect = blk_disconnect,
.event = blk_event,
.free = blk_free,
};