The BDRV_O_PROTOCOL flag should have an impact only if no driver is specified explicitly. Therefore, if bdrv_open() is called with an explicit block driver argument (either through the options QDict or through the drv parameter) and that block driver is a protocol block driver, BDRV_O_PROTOCOL should be set; if it is a format block driver, BDRV_O_PROTOCOL should be unset. While there was code to unset the flag in case a format block driver has been selected, it only followed the bdrv_fill_options() function call whereas the flag in fact needs to be adjusted before it is used there. With that change, BDRV_O_PROTOCOL will always be set if the BDS should be a protocol driver; if the driver has been specified explicitly, the new code will set it; and bdrv_fill_options() will only "probe" a protocol driver if BDRV_O_PROTOCOL is set. The probing after bdrv_fill_options() cannot select a protocol driver. Thus, bdrv_open_image() to open BDS.file is never called if a protocol BDS is about to be created. With that change in turn it is impossible to call bdrv_open_common() with a protocol drv and file != NULL, which allows us to remove the bdrv_swap() call. This change breaks a test case in qemu-iotest 051: "-drive file=t.qcow2,file.driver=qcow2" now works because the explicitly specified "qcow2" overrides the BDRV_O_PROTOCOL which is automatically set for the "file" BDS (and the filename is just passed down). Therefore, this patch removes that test case. Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
4041 lines
113 KiB
C
4041 lines
113 KiB
C
/*
|
|
* QEMU System Emulator block driver
|
|
*
|
|
* Copyright (c) 2003 Fabrice Bellard
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to deal
|
|
* in the Software without restriction, including without limitation the rights
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
* copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
|
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
* THE SOFTWARE.
|
|
*/
|
|
#include "config-host.h"
|
|
#include "qemu-common.h"
|
|
#include "trace.h"
|
|
#include "block/block_int.h"
|
|
#include "block/blockjob.h"
|
|
#include "qemu/module.h"
|
|
#include "qapi/qmp/qjson.h"
|
|
#include "sysemu/block-backend.h"
|
|
#include "sysemu/sysemu.h"
|
|
#include "qemu/notify.h"
|
|
#include "block/coroutine.h"
|
|
#include "block/qapi.h"
|
|
#include "qmp-commands.h"
|
|
#include "qemu/timer.h"
|
|
#include "qapi-event.h"
|
|
|
|
#ifdef CONFIG_BSD
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/queue.h>
|
|
#ifndef __DragonFly__
|
|
#include <sys/disk.h>
|
|
#endif
|
|
#endif
|
|
|
|
#ifdef _WIN32
|
|
#include <windows.h>
|
|
#endif
|
|
|
|
/**
|
|
* A BdrvDirtyBitmap can be in three possible states:
|
|
* (1) successor is NULL and disabled is false: full r/w mode
|
|
* (2) successor is NULL and disabled is true: read only mode ("disabled")
|
|
* (3) successor is set: frozen mode.
|
|
* A frozen bitmap cannot be renamed, deleted, anonymized, cleared, set,
|
|
* or enabled. A frozen bitmap can only abdicate() or reclaim().
|
|
*/
|
|
struct BdrvDirtyBitmap {
|
|
HBitmap *bitmap; /* Dirty sector bitmap implementation */
|
|
BdrvDirtyBitmap *successor; /* Anonymous child; implies frozen status */
|
|
char *name; /* Optional non-empty unique ID */
|
|
int64_t size; /* Size of the bitmap (Number of sectors) */
|
|
bool disabled; /* Bitmap is read-only */
|
|
QLIST_ENTRY(BdrvDirtyBitmap) list;
|
|
};
|
|
|
|
#define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */
|
|
|
|
static QTAILQ_HEAD(, BlockDriverState) bdrv_states =
|
|
QTAILQ_HEAD_INITIALIZER(bdrv_states);
|
|
|
|
static QTAILQ_HEAD(, BlockDriverState) graph_bdrv_states =
|
|
QTAILQ_HEAD_INITIALIZER(graph_bdrv_states);
|
|
|
|
static QLIST_HEAD(, BlockDriver) bdrv_drivers =
|
|
QLIST_HEAD_INITIALIZER(bdrv_drivers);
|
|
|
|
static void bdrv_dirty_bitmap_truncate(BlockDriverState *bs);
|
|
/* If non-zero, use only whitelisted block drivers */
|
|
static int use_bdrv_whitelist;
|
|
|
|
#ifdef _WIN32
|
|
static int is_windows_drive_prefix(const char *filename)
|
|
{
|
|
return (((filename[0] >= 'a' && filename[0] <= 'z') ||
|
|
(filename[0] >= 'A' && filename[0] <= 'Z')) &&
|
|
filename[1] == ':');
|
|
}
|
|
|
|
int is_windows_drive(const char *filename)
|
|
{
|
|
if (is_windows_drive_prefix(filename) &&
|
|
filename[2] == '\0')
|
|
return 1;
|
|
if (strstart(filename, "\\\\.\\", NULL) ||
|
|
strstart(filename, "//./", NULL))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
size_t bdrv_opt_mem_align(BlockDriverState *bs)
|
|
{
|
|
if (!bs || !bs->drv) {
|
|
/* page size or 4k (hdd sector size) should be on the safe side */
|
|
return MAX(4096, getpagesize());
|
|
}
|
|
|
|
return bs->bl.opt_mem_alignment;
|
|
}
|
|
|
|
size_t bdrv_min_mem_align(BlockDriverState *bs)
|
|
{
|
|
if (!bs || !bs->drv) {
|
|
/* page size or 4k (hdd sector size) should be on the safe side */
|
|
return MAX(4096, getpagesize());
|
|
}
|
|
|
|
return bs->bl.min_mem_alignment;
|
|
}
|
|
|
|
/* check if the path starts with "<protocol>:" */
|
|
int path_has_protocol(const char *path)
|
|
{
|
|
const char *p;
|
|
|
|
#ifdef _WIN32
|
|
if (is_windows_drive(path) ||
|
|
is_windows_drive_prefix(path)) {
|
|
return 0;
|
|
}
|
|
p = path + strcspn(path, ":/\\");
|
|
#else
|
|
p = path + strcspn(path, ":/");
|
|
#endif
|
|
|
|
return *p == ':';
|
|
}
|
|
|
|
int path_is_absolute(const char *path)
|
|
{
|
|
#ifdef _WIN32
|
|
/* specific case for names like: "\\.\d:" */
|
|
if (is_windows_drive(path) || is_windows_drive_prefix(path)) {
|
|
return 1;
|
|
}
|
|
return (*path == '/' || *path == '\\');
|
|
#else
|
|
return (*path == '/');
|
|
#endif
|
|
}
|
|
|
|
/* if filename is absolute, just copy it to dest. Otherwise, build a
|
|
path to it by considering it is relative to base_path. URL are
|
|
supported. */
|
|
void path_combine(char *dest, int dest_size,
|
|
const char *base_path,
|
|
const char *filename)
|
|
{
|
|
const char *p, *p1;
|
|
int len;
|
|
|
|
if (dest_size <= 0)
|
|
return;
|
|
if (path_is_absolute(filename)) {
|
|
pstrcpy(dest, dest_size, filename);
|
|
} else {
|
|
p = strchr(base_path, ':');
|
|
if (p)
|
|
p++;
|
|
else
|
|
p = base_path;
|
|
p1 = strrchr(base_path, '/');
|
|
#ifdef _WIN32
|
|
{
|
|
const char *p2;
|
|
p2 = strrchr(base_path, '\\');
|
|
if (!p1 || p2 > p1)
|
|
p1 = p2;
|
|
}
|
|
#endif
|
|
if (p1)
|
|
p1++;
|
|
else
|
|
p1 = base_path;
|
|
if (p1 > p)
|
|
p = p1;
|
|
len = p - base_path;
|
|
if (len > dest_size - 1)
|
|
len = dest_size - 1;
|
|
memcpy(dest, base_path, len);
|
|
dest[len] = '\0';
|
|
pstrcat(dest, dest_size, filename);
|
|
}
|
|
}
|
|
|
|
void bdrv_get_full_backing_filename_from_filename(const char *backed,
|
|
const char *backing,
|
|
char *dest, size_t sz,
|
|
Error **errp)
|
|
{
|
|
if (backing[0] == '\0' || path_has_protocol(backing) ||
|
|
path_is_absolute(backing))
|
|
{
|
|
pstrcpy(dest, sz, backing);
|
|
} else if (backed[0] == '\0' || strstart(backed, "json:", NULL)) {
|
|
error_setg(errp, "Cannot use relative backing file names for '%s'",
|
|
backed);
|
|
} else {
|
|
path_combine(dest, sz, backed, backing);
|
|
}
|
|
}
|
|
|
|
void bdrv_get_full_backing_filename(BlockDriverState *bs, char *dest, size_t sz,
|
|
Error **errp)
|
|
{
|
|
char *backed = bs->exact_filename[0] ? bs->exact_filename : bs->filename;
|
|
|
|
bdrv_get_full_backing_filename_from_filename(backed, bs->backing_file,
|
|
dest, sz, errp);
|
|
}
|
|
|
|
void bdrv_register(BlockDriver *bdrv)
|
|
{
|
|
bdrv_setup_io_funcs(bdrv);
|
|
|
|
QLIST_INSERT_HEAD(&bdrv_drivers, bdrv, list);
|
|
}
|
|
|
|
BlockDriverState *bdrv_new_root(void)
|
|
{
|
|
BlockDriverState *bs = bdrv_new();
|
|
|
|
QTAILQ_INSERT_TAIL(&bdrv_states, bs, device_list);
|
|
return bs;
|
|
}
|
|
|
|
BlockDriverState *bdrv_new(void)
|
|
{
|
|
BlockDriverState *bs;
|
|
int i;
|
|
|
|
bs = g_new0(BlockDriverState, 1);
|
|
QLIST_INIT(&bs->dirty_bitmaps);
|
|
for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) {
|
|
QLIST_INIT(&bs->op_blockers[i]);
|
|
}
|
|
bdrv_iostatus_disable(bs);
|
|
notifier_list_init(&bs->close_notifiers);
|
|
notifier_with_return_list_init(&bs->before_write_notifiers);
|
|
qemu_co_queue_init(&bs->throttled_reqs[0]);
|
|
qemu_co_queue_init(&bs->throttled_reqs[1]);
|
|
bs->refcnt = 1;
|
|
bs->aio_context = qemu_get_aio_context();
|
|
|
|
return bs;
|
|
}
|
|
|
|
void bdrv_add_close_notifier(BlockDriverState *bs, Notifier *notify)
|
|
{
|
|
notifier_list_add(&bs->close_notifiers, notify);
|
|
}
|
|
|
|
BlockDriver *bdrv_find_format(const char *format_name)
|
|
{
|
|
BlockDriver *drv1;
|
|
QLIST_FOREACH(drv1, &bdrv_drivers, list) {
|
|
if (!strcmp(drv1->format_name, format_name)) {
|
|
return drv1;
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static int bdrv_is_whitelisted(BlockDriver *drv, bool read_only)
|
|
{
|
|
static const char *whitelist_rw[] = {
|
|
CONFIG_BDRV_RW_WHITELIST
|
|
};
|
|
static const char *whitelist_ro[] = {
|
|
CONFIG_BDRV_RO_WHITELIST
|
|
};
|
|
const char **p;
|
|
|
|
if (!whitelist_rw[0] && !whitelist_ro[0]) {
|
|
return 1; /* no whitelist, anything goes */
|
|
}
|
|
|
|
for (p = whitelist_rw; *p; p++) {
|
|
if (!strcmp(drv->format_name, *p)) {
|
|
return 1;
|
|
}
|
|
}
|
|
if (read_only) {
|
|
for (p = whitelist_ro; *p; p++) {
|
|
if (!strcmp(drv->format_name, *p)) {
|
|
return 1;
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
BlockDriver *bdrv_find_whitelisted_format(const char *format_name,
|
|
bool read_only)
|
|
{
|
|
BlockDriver *drv = bdrv_find_format(format_name);
|
|
return drv && bdrv_is_whitelisted(drv, read_only) ? drv : NULL;
|
|
}
|
|
|
|
typedef struct CreateCo {
|
|
BlockDriver *drv;
|
|
char *filename;
|
|
QemuOpts *opts;
|
|
int ret;
|
|
Error *err;
|
|
} CreateCo;
|
|
|
|
static void coroutine_fn bdrv_create_co_entry(void *opaque)
|
|
{
|
|
Error *local_err = NULL;
|
|
int ret;
|
|
|
|
CreateCo *cco = opaque;
|
|
assert(cco->drv);
|
|
|
|
ret = cco->drv->bdrv_create(cco->filename, cco->opts, &local_err);
|
|
if (local_err) {
|
|
error_propagate(&cco->err, local_err);
|
|
}
|
|
cco->ret = ret;
|
|
}
|
|
|
|
int bdrv_create(BlockDriver *drv, const char* filename,
|
|
QemuOpts *opts, Error **errp)
|
|
{
|
|
int ret;
|
|
|
|
Coroutine *co;
|
|
CreateCo cco = {
|
|
.drv = drv,
|
|
.filename = g_strdup(filename),
|
|
.opts = opts,
|
|
.ret = NOT_DONE,
|
|
.err = NULL,
|
|
};
|
|
|
|
if (!drv->bdrv_create) {
|
|
error_setg(errp, "Driver '%s' does not support image creation", drv->format_name);
|
|
ret = -ENOTSUP;
|
|
goto out;
|
|
}
|
|
|
|
if (qemu_in_coroutine()) {
|
|
/* Fast-path if already in coroutine context */
|
|
bdrv_create_co_entry(&cco);
|
|
} else {
|
|
co = qemu_coroutine_create(bdrv_create_co_entry);
|
|
qemu_coroutine_enter(co, &cco);
|
|
while (cco.ret == NOT_DONE) {
|
|
aio_poll(qemu_get_aio_context(), true);
|
|
}
|
|
}
|
|
|
|
ret = cco.ret;
|
|
if (ret < 0) {
|
|
if (cco.err) {
|
|
error_propagate(errp, cco.err);
|
|
} else {
|
|
error_setg_errno(errp, -ret, "Could not create image");
|
|
}
|
|
}
|
|
|
|
out:
|
|
g_free(cco.filename);
|
|
return ret;
|
|
}
|
|
|
|
int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp)
|
|
{
|
|
BlockDriver *drv;
|
|
Error *local_err = NULL;
|
|
int ret;
|
|
|
|
drv = bdrv_find_protocol(filename, true, errp);
|
|
if (drv == NULL) {
|
|
return -ENOENT;
|
|
}
|
|
|
|
ret = bdrv_create(drv, filename, opts, &local_err);
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* Try to get @bs's logical and physical block size.
|
|
* On success, store them in @bsz struct and return 0.
|
|
* On failure return -errno.
|
|
* @bs must not be empty.
|
|
*/
|
|
int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
|
|
if (drv && drv->bdrv_probe_blocksizes) {
|
|
return drv->bdrv_probe_blocksizes(bs, bsz);
|
|
}
|
|
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
/**
|
|
* Try to get @bs's geometry (cyls, heads, sectors).
|
|
* On success, store them in @geo struct and return 0.
|
|
* On failure return -errno.
|
|
* @bs must not be empty.
|
|
*/
|
|
int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
|
|
if (drv && drv->bdrv_probe_geometry) {
|
|
return drv->bdrv_probe_geometry(bs, geo);
|
|
}
|
|
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
/*
|
|
* Create a uniquely-named empty temporary file.
|
|
* Return 0 upon success, otherwise a negative errno value.
|
|
*/
|
|
int get_tmp_filename(char *filename, int size)
|
|
{
|
|
#ifdef _WIN32
|
|
char temp_dir[MAX_PATH];
|
|
/* GetTempFileName requires that its output buffer (4th param)
|
|
have length MAX_PATH or greater. */
|
|
assert(size >= MAX_PATH);
|
|
return (GetTempPath(MAX_PATH, temp_dir)
|
|
&& GetTempFileName(temp_dir, "qem", 0, filename)
|
|
? 0 : -GetLastError());
|
|
#else
|
|
int fd;
|
|
const char *tmpdir;
|
|
tmpdir = getenv("TMPDIR");
|
|
if (!tmpdir) {
|
|
tmpdir = "/var/tmp";
|
|
}
|
|
if (snprintf(filename, size, "%s/vl.XXXXXX", tmpdir) >= size) {
|
|
return -EOVERFLOW;
|
|
}
|
|
fd = mkstemp(filename);
|
|
if (fd < 0) {
|
|
return -errno;
|
|
}
|
|
if (close(fd) != 0) {
|
|
unlink(filename);
|
|
return -errno;
|
|
}
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Detect host devices. By convention, /dev/cdrom[N] is always
|
|
* recognized as a host CDROM.
|
|
*/
|
|
static BlockDriver *find_hdev_driver(const char *filename)
|
|
{
|
|
int score_max = 0, score;
|
|
BlockDriver *drv = NULL, *d;
|
|
|
|
QLIST_FOREACH(d, &bdrv_drivers, list) {
|
|
if (d->bdrv_probe_device) {
|
|
score = d->bdrv_probe_device(filename);
|
|
if (score > score_max) {
|
|
score_max = score;
|
|
drv = d;
|
|
}
|
|
}
|
|
}
|
|
|
|
return drv;
|
|
}
|
|
|
|
BlockDriver *bdrv_find_protocol(const char *filename,
|
|
bool allow_protocol_prefix,
|
|
Error **errp)
|
|
{
|
|
BlockDriver *drv1;
|
|
char protocol[128];
|
|
int len;
|
|
const char *p;
|
|
|
|
/* TODO Drivers without bdrv_file_open must be specified explicitly */
|
|
|
|
/*
|
|
* XXX(hch): we really should not let host device detection
|
|
* override an explicit protocol specification, but moving this
|
|
* later breaks access to device names with colons in them.
|
|
* Thanks to the brain-dead persistent naming schemes on udev-
|
|
* based Linux systems those actually are quite common.
|
|
*/
|
|
drv1 = find_hdev_driver(filename);
|
|
if (drv1) {
|
|
return drv1;
|
|
}
|
|
|
|
if (!path_has_protocol(filename) || !allow_protocol_prefix) {
|
|
return &bdrv_file;
|
|
}
|
|
|
|
p = strchr(filename, ':');
|
|
assert(p != NULL);
|
|
len = p - filename;
|
|
if (len > sizeof(protocol) - 1)
|
|
len = sizeof(protocol) - 1;
|
|
memcpy(protocol, filename, len);
|
|
protocol[len] = '\0';
|
|
QLIST_FOREACH(drv1, &bdrv_drivers, list) {
|
|
if (drv1->protocol_name &&
|
|
!strcmp(drv1->protocol_name, protocol)) {
|
|
return drv1;
|
|
}
|
|
}
|
|
|
|
error_setg(errp, "Unknown protocol '%s'", protocol);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Guess image format by probing its contents.
|
|
* This is not a good idea when your image is raw (CVE-2008-2004), but
|
|
* we do it anyway for backward compatibility.
|
|
*
|
|
* @buf contains the image's first @buf_size bytes.
|
|
* @buf_size is the buffer size in bytes (generally BLOCK_PROBE_BUF_SIZE,
|
|
* but can be smaller if the image file is smaller)
|
|
* @filename is its filename.
|
|
*
|
|
* For all block drivers, call the bdrv_probe() method to get its
|
|
* probing score.
|
|
* Return the first block driver with the highest probing score.
|
|
*/
|
|
BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size,
|
|
const char *filename)
|
|
{
|
|
int score_max = 0, score;
|
|
BlockDriver *drv = NULL, *d;
|
|
|
|
QLIST_FOREACH(d, &bdrv_drivers, list) {
|
|
if (d->bdrv_probe) {
|
|
score = d->bdrv_probe(buf, buf_size, filename);
|
|
if (score > score_max) {
|
|
score_max = score;
|
|
drv = d;
|
|
}
|
|
}
|
|
}
|
|
|
|
return drv;
|
|
}
|
|
|
|
static int find_image_format(BlockDriverState *bs, const char *filename,
|
|
BlockDriver **pdrv, Error **errp)
|
|
{
|
|
BlockDriver *drv;
|
|
uint8_t buf[BLOCK_PROBE_BUF_SIZE];
|
|
int ret = 0;
|
|
|
|
/* Return the raw BlockDriver * to scsi-generic devices or empty drives */
|
|
if (bs->sg || !bdrv_is_inserted(bs) || bdrv_getlength(bs) == 0) {
|
|
*pdrv = &bdrv_raw;
|
|
return ret;
|
|
}
|
|
|
|
ret = bdrv_pread(bs, 0, buf, sizeof(buf));
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Could not read image for determining its "
|
|
"format");
|
|
*pdrv = NULL;
|
|
return ret;
|
|
}
|
|
|
|
drv = bdrv_probe_all(buf, ret, filename);
|
|
if (!drv) {
|
|
error_setg(errp, "Could not determine image format: No compatible "
|
|
"driver found");
|
|
ret = -ENOENT;
|
|
}
|
|
*pdrv = drv;
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* Set the current 'total_sectors' value
|
|
* Return 0 on success, -errno on error.
|
|
*/
|
|
static int refresh_total_sectors(BlockDriverState *bs, int64_t hint)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
|
|
/* Do not attempt drv->bdrv_getlength() on scsi-generic devices */
|
|
if (bs->sg)
|
|
return 0;
|
|
|
|
/* query actual device if possible, otherwise just trust the hint */
|
|
if (drv->bdrv_getlength) {
|
|
int64_t length = drv->bdrv_getlength(bs);
|
|
if (length < 0) {
|
|
return length;
|
|
}
|
|
hint = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE);
|
|
}
|
|
|
|
bs->total_sectors = hint;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* Set open flags for a given discard mode
|
|
*
|
|
* Return 0 on success, -1 if the discard mode was invalid.
|
|
*/
|
|
int bdrv_parse_discard_flags(const char *mode, int *flags)
|
|
{
|
|
*flags &= ~BDRV_O_UNMAP;
|
|
|
|
if (!strcmp(mode, "off") || !strcmp(mode, "ignore")) {
|
|
/* do nothing */
|
|
} else if (!strcmp(mode, "on") || !strcmp(mode, "unmap")) {
|
|
*flags |= BDRV_O_UNMAP;
|
|
} else {
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* Set open flags for a given cache mode
|
|
*
|
|
* Return 0 on success, -1 if the cache mode was invalid.
|
|
*/
|
|
int bdrv_parse_cache_flags(const char *mode, int *flags)
|
|
{
|
|
*flags &= ~BDRV_O_CACHE_MASK;
|
|
|
|
if (!strcmp(mode, "off") || !strcmp(mode, "none")) {
|
|
*flags |= BDRV_O_NOCACHE | BDRV_O_CACHE_WB;
|
|
} else if (!strcmp(mode, "directsync")) {
|
|
*flags |= BDRV_O_NOCACHE;
|
|
} else if (!strcmp(mode, "writeback")) {
|
|
*flags |= BDRV_O_CACHE_WB;
|
|
} else if (!strcmp(mode, "unsafe")) {
|
|
*flags |= BDRV_O_CACHE_WB;
|
|
*flags |= BDRV_O_NO_FLUSH;
|
|
} else if (!strcmp(mode, "writethrough")) {
|
|
/* this is the default */
|
|
} else {
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Returns the flags that a temporary snapshot should get, based on the
|
|
* originally requested flags (the originally requested image will have flags
|
|
* like a backing file)
|
|
*/
|
|
static int bdrv_temp_snapshot_flags(int flags)
|
|
{
|
|
return (flags & ~BDRV_O_SNAPSHOT) | BDRV_O_TEMPORARY;
|
|
}
|
|
|
|
/*
|
|
* Returns the flags that bs->file should get, based on the given flags for
|
|
* the parent BDS
|
|
*/
|
|
static int bdrv_inherited_flags(int flags)
|
|
{
|
|
/* Enable protocol handling, disable format probing for bs->file */
|
|
flags |= BDRV_O_PROTOCOL;
|
|
|
|
/* Our block drivers take care to send flushes and respect unmap policy,
|
|
* so we can enable both unconditionally on lower layers. */
|
|
flags |= BDRV_O_CACHE_WB | BDRV_O_UNMAP;
|
|
|
|
/* Clear flags that only apply to the top layer */
|
|
flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_COPY_ON_READ);
|
|
|
|
return flags;
|
|
}
|
|
|
|
/*
|
|
* Returns the flags that bs->backing_hd should get, based on the given flags
|
|
* for the parent BDS
|
|
*/
|
|
static int bdrv_backing_flags(int flags)
|
|
{
|
|
/* backing files always opened read-only */
|
|
flags &= ~(BDRV_O_RDWR | BDRV_O_COPY_ON_READ);
|
|
|
|
/* snapshot=on is handled on the top layer */
|
|
flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_TEMPORARY);
|
|
|
|
return flags;
|
|
}
|
|
|
|
static int bdrv_open_flags(BlockDriverState *bs, int flags)
|
|
{
|
|
int open_flags = flags | BDRV_O_CACHE_WB;
|
|
|
|
/*
|
|
* Clear flags that are internal to the block layer before opening the
|
|
* image.
|
|
*/
|
|
open_flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_PROTOCOL);
|
|
|
|
/*
|
|
* Snapshots should be writable.
|
|
*/
|
|
if (flags & BDRV_O_TEMPORARY) {
|
|
open_flags |= BDRV_O_RDWR;
|
|
}
|
|
|
|
return open_flags;
|
|
}
|
|
|
|
static void bdrv_assign_node_name(BlockDriverState *bs,
|
|
const char *node_name,
|
|
Error **errp)
|
|
{
|
|
if (!node_name) {
|
|
return;
|
|
}
|
|
|
|
/* Check for empty string or invalid characters */
|
|
if (!id_wellformed(node_name)) {
|
|
error_setg(errp, "Invalid node name");
|
|
return;
|
|
}
|
|
|
|
/* takes care of avoiding namespaces collisions */
|
|
if (blk_by_name(node_name)) {
|
|
error_setg(errp, "node-name=%s is conflicting with a device id",
|
|
node_name);
|
|
return;
|
|
}
|
|
|
|
/* takes care of avoiding duplicates node names */
|
|
if (bdrv_find_node(node_name)) {
|
|
error_setg(errp, "Duplicate node name");
|
|
return;
|
|
}
|
|
|
|
/* copy node name into the bs and insert it into the graph list */
|
|
pstrcpy(bs->node_name, sizeof(bs->node_name), node_name);
|
|
QTAILQ_INSERT_TAIL(&graph_bdrv_states, bs, node_list);
|
|
}
|
|
|
|
/*
|
|
* Common part for opening disk images and files
|
|
*
|
|
* Removes all processed options from *options.
|
|
*/
|
|
static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file,
|
|
QDict *options, int flags, BlockDriver *drv, Error **errp)
|
|
{
|
|
int ret, open_flags;
|
|
const char *filename;
|
|
const char *node_name = NULL;
|
|
Error *local_err = NULL;
|
|
|
|
assert(drv != NULL);
|
|
assert(bs->file == NULL);
|
|
assert(options != NULL && bs->options != options);
|
|
|
|
if (file != NULL) {
|
|
filename = file->filename;
|
|
} else {
|
|
filename = qdict_get_try_str(options, "filename");
|
|
}
|
|
|
|
if (drv->bdrv_needs_filename && !filename) {
|
|
error_setg(errp, "The '%s' block driver requires a file name",
|
|
drv->format_name);
|
|
return -EINVAL;
|
|
}
|
|
|
|
trace_bdrv_open_common(bs, filename ?: "", flags, drv->format_name);
|
|
|
|
node_name = qdict_get_try_str(options, "node-name");
|
|
bdrv_assign_node_name(bs, node_name, &local_err);
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
return -EINVAL;
|
|
}
|
|
qdict_del(options, "node-name");
|
|
|
|
bs->open_flags = flags;
|
|
bs->guest_block_size = 512;
|
|
bs->request_alignment = 512;
|
|
bs->zero_beyond_eof = true;
|
|
open_flags = bdrv_open_flags(bs, flags);
|
|
bs->read_only = !(open_flags & BDRV_O_RDWR);
|
|
|
|
if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, bs->read_only)) {
|
|
error_setg(errp,
|
|
!bs->read_only && bdrv_is_whitelisted(drv, true)
|
|
? "Driver '%s' can only be used for read-only devices"
|
|
: "Driver '%s' is not whitelisted",
|
|
drv->format_name);
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
assert(bs->copy_on_read == 0); /* bdrv_new() and bdrv_close() make it so */
|
|
if (flags & BDRV_O_COPY_ON_READ) {
|
|
if (!bs->read_only) {
|
|
bdrv_enable_copy_on_read(bs);
|
|
} else {
|
|
error_setg(errp, "Can't use copy-on-read on read-only device");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
if (filename != NULL) {
|
|
pstrcpy(bs->filename, sizeof(bs->filename), filename);
|
|
} else {
|
|
bs->filename[0] = '\0';
|
|
}
|
|
pstrcpy(bs->exact_filename, sizeof(bs->exact_filename), bs->filename);
|
|
|
|
bs->drv = drv;
|
|
bs->opaque = g_malloc0(drv->instance_size);
|
|
|
|
bs->enable_write_cache = !!(flags & BDRV_O_CACHE_WB);
|
|
|
|
/* Open the image, either directly or using a protocol */
|
|
if (drv->bdrv_file_open) {
|
|
assert(file == NULL);
|
|
assert(!drv->bdrv_needs_filename || filename != NULL);
|
|
ret = drv->bdrv_file_open(bs, options, open_flags, &local_err);
|
|
} else {
|
|
if (file == NULL) {
|
|
error_setg(errp, "Can't use '%s' as a block driver for the "
|
|
"protocol level", drv->format_name);
|
|
ret = -EINVAL;
|
|
goto free_and_fail;
|
|
}
|
|
bs->file = file;
|
|
ret = drv->bdrv_open(bs, options, open_flags, &local_err);
|
|
}
|
|
|
|
if (ret < 0) {
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
} else if (bs->filename[0]) {
|
|
error_setg_errno(errp, -ret, "Could not open '%s'", bs->filename);
|
|
} else {
|
|
error_setg_errno(errp, -ret, "Could not open image");
|
|
}
|
|
goto free_and_fail;
|
|
}
|
|
|
|
if (bs->encrypted) {
|
|
error_report("Encrypted images are deprecated");
|
|
error_printf("Support for them will be removed in a future release.\n"
|
|
"You can use 'qemu-img convert' to convert your image"
|
|
" to an unencrypted one.\n");
|
|
}
|
|
|
|
ret = refresh_total_sectors(bs, bs->total_sectors);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Could not refresh total sector count");
|
|
goto free_and_fail;
|
|
}
|
|
|
|
bdrv_refresh_limits(bs, &local_err);
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
ret = -EINVAL;
|
|
goto free_and_fail;
|
|
}
|
|
|
|
assert(bdrv_opt_mem_align(bs) != 0);
|
|
assert(bdrv_min_mem_align(bs) != 0);
|
|
assert((bs->request_alignment != 0) || bs->sg);
|
|
return 0;
|
|
|
|
free_and_fail:
|
|
bs->file = NULL;
|
|
g_free(bs->opaque);
|
|
bs->opaque = NULL;
|
|
bs->drv = NULL;
|
|
return ret;
|
|
}
|
|
|
|
static QDict *parse_json_filename(const char *filename, Error **errp)
|
|
{
|
|
QObject *options_obj;
|
|
QDict *options;
|
|
int ret;
|
|
|
|
ret = strstart(filename, "json:", &filename);
|
|
assert(ret);
|
|
|
|
options_obj = qobject_from_json(filename);
|
|
if (!options_obj) {
|
|
error_setg(errp, "Could not parse the JSON options");
|
|
return NULL;
|
|
}
|
|
|
|
if (qobject_type(options_obj) != QTYPE_QDICT) {
|
|
qobject_decref(options_obj);
|
|
error_setg(errp, "Invalid JSON object given");
|
|
return NULL;
|
|
}
|
|
|
|
options = qobject_to_qdict(options_obj);
|
|
qdict_flatten(options);
|
|
|
|
return options;
|
|
}
|
|
|
|
/*
|
|
* Fills in default options for opening images and converts the legacy
|
|
* filename/flags pair to option QDict entries.
|
|
* The BDRV_O_PROTOCOL flag in *flags will be set or cleared accordingly if a
|
|
* block driver has been specified explicitly.
|
|
*/
|
|
static int bdrv_fill_options(QDict **options, const char **pfilename,
|
|
int *flags, BlockDriver *drv, Error **errp)
|
|
{
|
|
const char *filename = *pfilename;
|
|
const char *drvname;
|
|
bool protocol = *flags & BDRV_O_PROTOCOL;
|
|
bool parse_filename = false;
|
|
BlockDriver *tmp_drv;
|
|
Error *local_err = NULL;
|
|
|
|
/* Parse json: pseudo-protocol */
|
|
if (filename && g_str_has_prefix(filename, "json:")) {
|
|
QDict *json_options = parse_json_filename(filename, &local_err);
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Options given in the filename have lower priority than options
|
|
* specified directly */
|
|
qdict_join(*options, json_options, false);
|
|
QDECREF(json_options);
|
|
*pfilename = filename = NULL;
|
|
}
|
|
|
|
drvname = qdict_get_try_str(*options, "driver");
|
|
|
|
/* If the user has explicitly specified the driver, this choice should
|
|
* override the BDRV_O_PROTOCOL flag */
|
|
tmp_drv = drv;
|
|
if (!tmp_drv && drvname) {
|
|
tmp_drv = bdrv_find_format(drvname);
|
|
}
|
|
if (tmp_drv) {
|
|
protocol = tmp_drv->bdrv_file_open;
|
|
}
|
|
|
|
if (protocol) {
|
|
*flags |= BDRV_O_PROTOCOL;
|
|
} else {
|
|
*flags &= ~BDRV_O_PROTOCOL;
|
|
}
|
|
|
|
/* Fetch the file name from the options QDict if necessary */
|
|
if (protocol && filename) {
|
|
if (!qdict_haskey(*options, "filename")) {
|
|
qdict_put(*options, "filename", qstring_from_str(filename));
|
|
parse_filename = true;
|
|
} else {
|
|
error_setg(errp, "Can't specify 'file' and 'filename' options at "
|
|
"the same time");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
/* Find the right block driver */
|
|
filename = qdict_get_try_str(*options, "filename");
|
|
|
|
if (drv) {
|
|
if (drvname) {
|
|
error_setg(errp, "Driver specified twice");
|
|
return -EINVAL;
|
|
}
|
|
drvname = drv->format_name;
|
|
qdict_put(*options, "driver", qstring_from_str(drvname));
|
|
} else {
|
|
if (!drvname && protocol) {
|
|
if (filename) {
|
|
drv = bdrv_find_protocol(filename, parse_filename, errp);
|
|
if (!drv) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
drvname = drv->format_name;
|
|
qdict_put(*options, "driver", qstring_from_str(drvname));
|
|
} else {
|
|
error_setg(errp, "Must specify either driver or file");
|
|
return -EINVAL;
|
|
}
|
|
} else if (drvname) {
|
|
drv = bdrv_find_format(drvname);
|
|
if (!drv) {
|
|
error_setg(errp, "Unknown driver '%s'", drvname);
|
|
return -ENOENT;
|
|
}
|
|
}
|
|
}
|
|
|
|
assert(drv || !protocol);
|
|
|
|
/* Driver-specific filename parsing */
|
|
if (drv && drv->bdrv_parse_filename && parse_filename) {
|
|
drv->bdrv_parse_filename(filename, *options, &local_err);
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!drv->bdrv_needs_filename) {
|
|
qdict_del(*options, "filename");
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
|
|
{
|
|
|
|
if (bs->backing_hd) {
|
|
assert(bs->backing_blocker);
|
|
bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
|
|
} else if (backing_hd) {
|
|
error_setg(&bs->backing_blocker,
|
|
"node is used as backing hd of '%s'",
|
|
bdrv_get_device_or_node_name(bs));
|
|
}
|
|
|
|
bs->backing_hd = backing_hd;
|
|
if (!backing_hd) {
|
|
error_free(bs->backing_blocker);
|
|
bs->backing_blocker = NULL;
|
|
goto out;
|
|
}
|
|
bs->open_flags &= ~BDRV_O_NO_BACKING;
|
|
pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename);
|
|
pstrcpy(bs->backing_format, sizeof(bs->backing_format),
|
|
backing_hd->drv ? backing_hd->drv->format_name : "");
|
|
|
|
bdrv_op_block_all(bs->backing_hd, bs->backing_blocker);
|
|
/* Otherwise we won't be able to commit due to check in bdrv_commit */
|
|
bdrv_op_unblock(bs->backing_hd, BLOCK_OP_TYPE_COMMIT_TARGET,
|
|
bs->backing_blocker);
|
|
out:
|
|
bdrv_refresh_limits(bs, NULL);
|
|
}
|
|
|
|
/*
|
|
* Opens the backing file for a BlockDriverState if not yet open
|
|
*
|
|
* options is a QDict of options to pass to the block drivers, or NULL for an
|
|
* empty set of options. The reference to the QDict is transferred to this
|
|
* function (even on failure), so if the caller intends to reuse the dictionary,
|
|
* it needs to use QINCREF() before calling bdrv_file_open.
|
|
*/
|
|
int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp)
|
|
{
|
|
char *backing_filename = g_malloc0(PATH_MAX);
|
|
int ret = 0;
|
|
BlockDriverState *backing_hd;
|
|
Error *local_err = NULL;
|
|
|
|
if (bs->backing_hd != NULL) {
|
|
QDECREF(options);
|
|
goto free_exit;
|
|
}
|
|
|
|
/* NULL means an empty set of options */
|
|
if (options == NULL) {
|
|
options = qdict_new();
|
|
}
|
|
|
|
bs->open_flags &= ~BDRV_O_NO_BACKING;
|
|
if (qdict_haskey(options, "file.filename")) {
|
|
backing_filename[0] = '\0';
|
|
} else if (bs->backing_file[0] == '\0' && qdict_size(options) == 0) {
|
|
QDECREF(options);
|
|
goto free_exit;
|
|
} else {
|
|
bdrv_get_full_backing_filename(bs, backing_filename, PATH_MAX,
|
|
&local_err);
|
|
if (local_err) {
|
|
ret = -EINVAL;
|
|
error_propagate(errp, local_err);
|
|
QDECREF(options);
|
|
goto free_exit;
|
|
}
|
|
}
|
|
|
|
if (!bs->drv || !bs->drv->supports_backing) {
|
|
ret = -EINVAL;
|
|
error_setg(errp, "Driver doesn't support backing files");
|
|
QDECREF(options);
|
|
goto free_exit;
|
|
}
|
|
|
|
backing_hd = bdrv_new();
|
|
|
|
if (bs->backing_format[0] != '\0' && !qdict_haskey(options, "driver")) {
|
|
qdict_put(options, "driver", qstring_from_str(bs->backing_format));
|
|
}
|
|
|
|
assert(bs->backing_hd == NULL);
|
|
ret = bdrv_open(&backing_hd,
|
|
*backing_filename ? backing_filename : NULL, NULL, options,
|
|
bdrv_backing_flags(bs->open_flags), NULL, &local_err);
|
|
if (ret < 0) {
|
|
bdrv_unref(backing_hd);
|
|
backing_hd = NULL;
|
|
bs->open_flags |= BDRV_O_NO_BACKING;
|
|
error_setg(errp, "Could not open backing file: %s",
|
|
error_get_pretty(local_err));
|
|
error_free(local_err);
|
|
goto free_exit;
|
|
}
|
|
bdrv_set_backing_hd(bs, backing_hd);
|
|
|
|
free_exit:
|
|
g_free(backing_filename);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Opens a disk image whose options are given as BlockdevRef in another block
|
|
* device's options.
|
|
*
|
|
* If allow_none is true, no image will be opened if filename is false and no
|
|
* BlockdevRef is given. *pbs will remain unchanged and 0 will be returned.
|
|
*
|
|
* bdrev_key specifies the key for the image's BlockdevRef in the options QDict.
|
|
* That QDict has to be flattened; therefore, if the BlockdevRef is a QDict
|
|
* itself, all options starting with "${bdref_key}." are considered part of the
|
|
* BlockdevRef.
|
|
*
|
|
* The BlockdevRef will be removed from the options QDict.
|
|
*
|
|
* To conform with the behavior of bdrv_open(), *pbs has to be NULL.
|
|
*/
|
|
int bdrv_open_image(BlockDriverState **pbs, const char *filename,
|
|
QDict *options, const char *bdref_key, int flags,
|
|
bool allow_none, Error **errp)
|
|
{
|
|
QDict *image_options;
|
|
int ret;
|
|
char *bdref_key_dot;
|
|
const char *reference;
|
|
|
|
assert(pbs);
|
|
assert(*pbs == NULL);
|
|
|
|
bdref_key_dot = g_strdup_printf("%s.", bdref_key);
|
|
qdict_extract_subqdict(options, &image_options, bdref_key_dot);
|
|
g_free(bdref_key_dot);
|
|
|
|
reference = qdict_get_try_str(options, bdref_key);
|
|
if (!filename && !reference && !qdict_size(image_options)) {
|
|
if (allow_none) {
|
|
ret = 0;
|
|
} else {
|
|
error_setg(errp, "A block device must be specified for \"%s\"",
|
|
bdref_key);
|
|
ret = -EINVAL;
|
|
}
|
|
QDECREF(image_options);
|
|
goto done;
|
|
}
|
|
|
|
ret = bdrv_open(pbs, filename, reference, image_options, flags, NULL, errp);
|
|
|
|
done:
|
|
qdict_del(options, bdref_key);
|
|
return ret;
|
|
}
|
|
|
|
int bdrv_append_temp_snapshot(BlockDriverState *bs, int flags, Error **errp)
|
|
{
|
|
/* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */
|
|
char *tmp_filename = g_malloc0(PATH_MAX + 1);
|
|
int64_t total_size;
|
|
QemuOpts *opts = NULL;
|
|
QDict *snapshot_options;
|
|
BlockDriverState *bs_snapshot;
|
|
Error *local_err;
|
|
int ret;
|
|
|
|
/* if snapshot, we create a temporary backing file and open it
|
|
instead of opening 'filename' directly */
|
|
|
|
/* Get the required size from the image */
|
|
total_size = bdrv_getlength(bs);
|
|
if (total_size < 0) {
|
|
ret = total_size;
|
|
error_setg_errno(errp, -total_size, "Could not get image size");
|
|
goto out;
|
|
}
|
|
|
|
/* Create the temporary image */
|
|
ret = get_tmp_filename(tmp_filename, PATH_MAX + 1);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Could not get temporary filename");
|
|
goto out;
|
|
}
|
|
|
|
opts = qemu_opts_create(bdrv_qcow2.create_opts, NULL, 0,
|
|
&error_abort);
|
|
qemu_opt_set_number(opts, BLOCK_OPT_SIZE, total_size, &error_abort);
|
|
ret = bdrv_create(&bdrv_qcow2, tmp_filename, opts, &local_err);
|
|
qemu_opts_del(opts);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Could not create temporary overlay "
|
|
"'%s': %s", tmp_filename,
|
|
error_get_pretty(local_err));
|
|
error_free(local_err);
|
|
goto out;
|
|
}
|
|
|
|
/* Prepare a new options QDict for the temporary file */
|
|
snapshot_options = qdict_new();
|
|
qdict_put(snapshot_options, "file.driver",
|
|
qstring_from_str("file"));
|
|
qdict_put(snapshot_options, "file.filename",
|
|
qstring_from_str(tmp_filename));
|
|
|
|
bs_snapshot = bdrv_new();
|
|
|
|
ret = bdrv_open(&bs_snapshot, NULL, NULL, snapshot_options,
|
|
flags, &bdrv_qcow2, &local_err);
|
|
if (ret < 0) {
|
|
error_propagate(errp, local_err);
|
|
goto out;
|
|
}
|
|
|
|
bdrv_append(bs_snapshot, bs);
|
|
|
|
out:
|
|
g_free(tmp_filename);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Opens a disk image (raw, qcow2, vmdk, ...)
|
|
*
|
|
* options is a QDict of options to pass to the block drivers, or NULL for an
|
|
* empty set of options. The reference to the QDict belongs to the block layer
|
|
* after the call (even on failure), so if the caller intends to reuse the
|
|
* dictionary, it needs to use QINCREF() before calling bdrv_open.
|
|
*
|
|
* If *pbs is NULL, a new BDS will be created with a pointer to it stored there.
|
|
* If it is not NULL, the referenced BDS will be reused.
|
|
*
|
|
* The reference parameter may be used to specify an existing block device which
|
|
* should be opened. If specified, neither options nor a filename may be given,
|
|
* nor can an existing BDS be reused (that is, *pbs has to be NULL).
|
|
*/
|
|
int bdrv_open(BlockDriverState **pbs, const char *filename,
|
|
const char *reference, QDict *options, int flags,
|
|
BlockDriver *drv, Error **errp)
|
|
{
|
|
int ret;
|
|
BlockDriverState *file = NULL, *bs;
|
|
const char *drvname;
|
|
Error *local_err = NULL;
|
|
int snapshot_flags = 0;
|
|
|
|
assert(pbs);
|
|
|
|
if (reference) {
|
|
bool options_non_empty = options ? qdict_size(options) : false;
|
|
QDECREF(options);
|
|
|
|
if (*pbs) {
|
|
error_setg(errp, "Cannot reuse an existing BDS when referencing "
|
|
"another block device");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (filename || options_non_empty) {
|
|
error_setg(errp, "Cannot reference an existing block device with "
|
|
"additional options or a new filename");
|
|
return -EINVAL;
|
|
}
|
|
|
|
bs = bdrv_lookup_bs(reference, reference, errp);
|
|
if (!bs) {
|
|
return -ENODEV;
|
|
}
|
|
bdrv_ref(bs);
|
|
*pbs = bs;
|
|
return 0;
|
|
}
|
|
|
|
if (*pbs) {
|
|
bs = *pbs;
|
|
} else {
|
|
bs = bdrv_new();
|
|
}
|
|
|
|
/* NULL means an empty set of options */
|
|
if (options == NULL) {
|
|
options = qdict_new();
|
|
}
|
|
|
|
ret = bdrv_fill_options(&options, &filename, &flags, drv, &local_err);
|
|
if (local_err) {
|
|
goto fail;
|
|
}
|
|
|
|
/* Find the right image format driver */
|
|
drv = NULL;
|
|
drvname = qdict_get_try_str(options, "driver");
|
|
if (drvname) {
|
|
drv = bdrv_find_format(drvname);
|
|
qdict_del(options, "driver");
|
|
if (!drv) {
|
|
error_setg(errp, "Unknown driver: '%s'", drvname);
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
}
|
|
|
|
assert(drvname || !(flags & BDRV_O_PROTOCOL));
|
|
|
|
bs->options = options;
|
|
options = qdict_clone_shallow(options);
|
|
|
|
/* Open image file without format layer */
|
|
if ((flags & BDRV_O_PROTOCOL) == 0) {
|
|
if (flags & BDRV_O_RDWR) {
|
|
flags |= BDRV_O_ALLOW_RDWR;
|
|
}
|
|
if (flags & BDRV_O_SNAPSHOT) {
|
|
snapshot_flags = bdrv_temp_snapshot_flags(flags);
|
|
flags = bdrv_backing_flags(flags);
|
|
}
|
|
|
|
assert(file == NULL);
|
|
ret = bdrv_open_image(&file, filename, options, "file",
|
|
bdrv_inherited_flags(flags),
|
|
true, &local_err);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
}
|
|
|
|
/* Image format probing */
|
|
bs->probed = !drv;
|
|
if (!drv && file) {
|
|
ret = find_image_format(file, filename, &drv, &local_err);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
} else if (!drv) {
|
|
error_setg(errp, "Must specify either driver or file");
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
/* BDRV_O_PROTOCOL must be set iff a protocol BDS is about to be created */
|
|
assert(!!(flags & BDRV_O_PROTOCOL) == !!drv->bdrv_file_open);
|
|
/* file must be NULL if a protocol BDS is about to be created
|
|
* (the inverse results in an error message from bdrv_open_common()) */
|
|
assert(!(flags & BDRV_O_PROTOCOL) || !file);
|
|
|
|
/* Open the image */
|
|
ret = bdrv_open_common(bs, file, options, flags, drv, &local_err);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
|
|
if (file && (bs->file != file)) {
|
|
bdrv_unref(file);
|
|
file = NULL;
|
|
}
|
|
|
|
/* If there is a backing file, use it */
|
|
if ((flags & BDRV_O_NO_BACKING) == 0) {
|
|
QDict *backing_options;
|
|
|
|
qdict_extract_subqdict(options, &backing_options, "backing.");
|
|
ret = bdrv_open_backing_file(bs, backing_options, &local_err);
|
|
if (ret < 0) {
|
|
goto close_and_fail;
|
|
}
|
|
}
|
|
|
|
bdrv_refresh_filename(bs);
|
|
|
|
/* For snapshot=on, create a temporary qcow2 overlay. bs points to the
|
|
* temporary snapshot afterwards. */
|
|
if (snapshot_flags) {
|
|
ret = bdrv_append_temp_snapshot(bs, snapshot_flags, &local_err);
|
|
if (local_err) {
|
|
goto close_and_fail;
|
|
}
|
|
}
|
|
|
|
/* Check if any unknown options were used */
|
|
if (options && (qdict_size(options) != 0)) {
|
|
const QDictEntry *entry = qdict_first(options);
|
|
if (flags & BDRV_O_PROTOCOL) {
|
|
error_setg(errp, "Block protocol '%s' doesn't support the option "
|
|
"'%s'", drv->format_name, entry->key);
|
|
} else {
|
|
error_setg(errp, "Block format '%s' used by device '%s' doesn't "
|
|
"support the option '%s'", drv->format_name,
|
|
bdrv_get_device_name(bs), entry->key);
|
|
}
|
|
|
|
ret = -EINVAL;
|
|
goto close_and_fail;
|
|
}
|
|
|
|
if (!bdrv_key_required(bs)) {
|
|
if (bs->blk) {
|
|
blk_dev_change_media_cb(bs->blk, true);
|
|
}
|
|
} else if (!runstate_check(RUN_STATE_PRELAUNCH)
|
|
&& !runstate_check(RUN_STATE_INMIGRATE)
|
|
&& !runstate_check(RUN_STATE_PAUSED)) { /* HACK */
|
|
error_setg(errp,
|
|
"Guest must be stopped for opening of encrypted image");
|
|
ret = -EBUSY;
|
|
goto close_and_fail;
|
|
}
|
|
|
|
QDECREF(options);
|
|
*pbs = bs;
|
|
return 0;
|
|
|
|
fail:
|
|
if (file != NULL) {
|
|
bdrv_unref(file);
|
|
}
|
|
QDECREF(bs->options);
|
|
QDECREF(options);
|
|
bs->options = NULL;
|
|
if (!*pbs) {
|
|
/* If *pbs is NULL, a new BDS has been created in this function and
|
|
needs to be freed now. Otherwise, it does not need to be closed,
|
|
since it has not really been opened yet. */
|
|
bdrv_unref(bs);
|
|
}
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
}
|
|
return ret;
|
|
|
|
close_and_fail:
|
|
/* See fail path, but now the BDS has to be always closed */
|
|
if (*pbs) {
|
|
bdrv_close(bs);
|
|
} else {
|
|
bdrv_unref(bs);
|
|
}
|
|
QDECREF(options);
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
typedef struct BlockReopenQueueEntry {
|
|
bool prepared;
|
|
BDRVReopenState state;
|
|
QSIMPLEQ_ENTRY(BlockReopenQueueEntry) entry;
|
|
} BlockReopenQueueEntry;
|
|
|
|
/*
|
|
* Adds a BlockDriverState to a simple queue for an atomic, transactional
|
|
* reopen of multiple devices.
|
|
*
|
|
* bs_queue can either be an existing BlockReopenQueue that has had QSIMPLE_INIT
|
|
* already performed, or alternatively may be NULL a new BlockReopenQueue will
|
|
* be created and initialized. This newly created BlockReopenQueue should be
|
|
* passed back in for subsequent calls that are intended to be of the same
|
|
* atomic 'set'.
|
|
*
|
|
* bs is the BlockDriverState to add to the reopen queue.
|
|
*
|
|
* flags contains the open flags for the associated bs
|
|
*
|
|
* returns a pointer to bs_queue, which is either the newly allocated
|
|
* bs_queue, or the existing bs_queue being used.
|
|
*
|
|
*/
|
|
BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
|
|
BlockDriverState *bs, int flags)
|
|
{
|
|
assert(bs != NULL);
|
|
|
|
BlockReopenQueueEntry *bs_entry;
|
|
if (bs_queue == NULL) {
|
|
bs_queue = g_new0(BlockReopenQueue, 1);
|
|
QSIMPLEQ_INIT(bs_queue);
|
|
}
|
|
|
|
/* bdrv_open() masks this flag out */
|
|
flags &= ~BDRV_O_PROTOCOL;
|
|
|
|
if (bs->file) {
|
|
bdrv_reopen_queue(bs_queue, bs->file, bdrv_inherited_flags(flags));
|
|
}
|
|
|
|
bs_entry = g_new0(BlockReopenQueueEntry, 1);
|
|
QSIMPLEQ_INSERT_TAIL(bs_queue, bs_entry, entry);
|
|
|
|
bs_entry->state.bs = bs;
|
|
bs_entry->state.flags = flags;
|
|
|
|
return bs_queue;
|
|
}
|
|
|
|
/*
|
|
* Reopen multiple BlockDriverStates atomically & transactionally.
|
|
*
|
|
* The queue passed in (bs_queue) must have been built up previous
|
|
* via bdrv_reopen_queue().
|
|
*
|
|
* Reopens all BDS specified in the queue, with the appropriate
|
|
* flags. All devices are prepared for reopen, and failure of any
|
|
* device will cause all device changes to be abandonded, and intermediate
|
|
* data cleaned up.
|
|
*
|
|
* If all devices prepare successfully, then the changes are committed
|
|
* to all devices.
|
|
*
|
|
*/
|
|
int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp)
|
|
{
|
|
int ret = -1;
|
|
BlockReopenQueueEntry *bs_entry, *next;
|
|
Error *local_err = NULL;
|
|
|
|
assert(bs_queue != NULL);
|
|
|
|
bdrv_drain_all();
|
|
|
|
QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) {
|
|
if (bdrv_reopen_prepare(&bs_entry->state, bs_queue, &local_err)) {
|
|
error_propagate(errp, local_err);
|
|
goto cleanup;
|
|
}
|
|
bs_entry->prepared = true;
|
|
}
|
|
|
|
/* If we reach this point, we have success and just need to apply the
|
|
* changes
|
|
*/
|
|
QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) {
|
|
bdrv_reopen_commit(&bs_entry->state);
|
|
}
|
|
|
|
ret = 0;
|
|
|
|
cleanup:
|
|
QSIMPLEQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) {
|
|
if (ret && bs_entry->prepared) {
|
|
bdrv_reopen_abort(&bs_entry->state);
|
|
}
|
|
g_free(bs_entry);
|
|
}
|
|
g_free(bs_queue);
|
|
return ret;
|
|
}
|
|
|
|
|
|
/* Reopen a single BlockDriverState with the specified flags. */
|
|
int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp)
|
|
{
|
|
int ret = -1;
|
|
Error *local_err = NULL;
|
|
BlockReopenQueue *queue = bdrv_reopen_queue(NULL, bs, bdrv_flags);
|
|
|
|
ret = bdrv_reopen_multiple(queue, &local_err);
|
|
if (local_err != NULL) {
|
|
error_propagate(errp, local_err);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
|
|
/*
|
|
* Prepares a BlockDriverState for reopen. All changes are staged in the
|
|
* 'opaque' field of the BDRVReopenState, which is used and allocated by
|
|
* the block driver layer .bdrv_reopen_prepare()
|
|
*
|
|
* bs is the BlockDriverState to reopen
|
|
* flags are the new open flags
|
|
* queue is the reopen queue
|
|
*
|
|
* Returns 0 on success, non-zero on error. On error errp will be set
|
|
* as well.
|
|
*
|
|
* On failure, bdrv_reopen_abort() will be called to clean up any data.
|
|
* It is the responsibility of the caller to then call the abort() or
|
|
* commit() for any other BDS that have been left in a prepare() state
|
|
*
|
|
*/
|
|
int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue,
|
|
Error **errp)
|
|
{
|
|
int ret = -1;
|
|
Error *local_err = NULL;
|
|
BlockDriver *drv;
|
|
|
|
assert(reopen_state != NULL);
|
|
assert(reopen_state->bs->drv != NULL);
|
|
drv = reopen_state->bs->drv;
|
|
|
|
/* if we are to stay read-only, do not allow permission change
|
|
* to r/w */
|
|
if (!(reopen_state->bs->open_flags & BDRV_O_ALLOW_RDWR) &&
|
|
reopen_state->flags & BDRV_O_RDWR) {
|
|
error_setg(errp, "Node '%s' is read only",
|
|
bdrv_get_device_or_node_name(reopen_state->bs));
|
|
goto error;
|
|
}
|
|
|
|
|
|
ret = bdrv_flush(reopen_state->bs);
|
|
if (ret) {
|
|
error_set(errp, ERROR_CLASS_GENERIC_ERROR, "Error (%s) flushing drive",
|
|
strerror(-ret));
|
|
goto error;
|
|
}
|
|
|
|
if (drv->bdrv_reopen_prepare) {
|
|
ret = drv->bdrv_reopen_prepare(reopen_state, queue, &local_err);
|
|
if (ret) {
|
|
if (local_err != NULL) {
|
|
error_propagate(errp, local_err);
|
|
} else {
|
|
error_setg(errp, "failed while preparing to reopen image '%s'",
|
|
reopen_state->bs->filename);
|
|
}
|
|
goto error;
|
|
}
|
|
} else {
|
|
/* It is currently mandatory to have a bdrv_reopen_prepare()
|
|
* handler for each supported drv. */
|
|
error_setg(errp, "Block format '%s' used by node '%s' "
|
|
"does not support reopening files", drv->format_name,
|
|
bdrv_get_device_or_node_name(reopen_state->bs));
|
|
ret = -1;
|
|
goto error;
|
|
}
|
|
|
|
ret = 0;
|
|
|
|
error:
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Takes the staged changes for the reopen from bdrv_reopen_prepare(), and
|
|
* makes them final by swapping the staging BlockDriverState contents into
|
|
* the active BlockDriverState contents.
|
|
*/
|
|
void bdrv_reopen_commit(BDRVReopenState *reopen_state)
|
|
{
|
|
BlockDriver *drv;
|
|
|
|
assert(reopen_state != NULL);
|
|
drv = reopen_state->bs->drv;
|
|
assert(drv != NULL);
|
|
|
|
/* If there are any driver level actions to take */
|
|
if (drv->bdrv_reopen_commit) {
|
|
drv->bdrv_reopen_commit(reopen_state);
|
|
}
|
|
|
|
/* set BDS specific flags now */
|
|
reopen_state->bs->open_flags = reopen_state->flags;
|
|
reopen_state->bs->enable_write_cache = !!(reopen_state->flags &
|
|
BDRV_O_CACHE_WB);
|
|
reopen_state->bs->read_only = !(reopen_state->flags & BDRV_O_RDWR);
|
|
|
|
bdrv_refresh_limits(reopen_state->bs, NULL);
|
|
}
|
|
|
|
/*
|
|
* Abort the reopen, and delete and free the staged changes in
|
|
* reopen_state
|
|
*/
|
|
void bdrv_reopen_abort(BDRVReopenState *reopen_state)
|
|
{
|
|
BlockDriver *drv;
|
|
|
|
assert(reopen_state != NULL);
|
|
drv = reopen_state->bs->drv;
|
|
assert(drv != NULL);
|
|
|
|
if (drv->bdrv_reopen_abort) {
|
|
drv->bdrv_reopen_abort(reopen_state);
|
|
}
|
|
}
|
|
|
|
|
|
void bdrv_close(BlockDriverState *bs)
|
|
{
|
|
BdrvAioNotifier *ban, *ban_next;
|
|
|
|
if (bs->job) {
|
|
block_job_cancel_sync(bs->job);
|
|
}
|
|
bdrv_drain_all(); /* complete I/O */
|
|
bdrv_flush(bs);
|
|
bdrv_drain_all(); /* in case flush left pending I/O */
|
|
notifier_list_notify(&bs->close_notifiers, bs);
|
|
|
|
if (bs->drv) {
|
|
if (bs->backing_hd) {
|
|
BlockDriverState *backing_hd = bs->backing_hd;
|
|
bdrv_set_backing_hd(bs, NULL);
|
|
bdrv_unref(backing_hd);
|
|
}
|
|
bs->drv->bdrv_close(bs);
|
|
g_free(bs->opaque);
|
|
bs->opaque = NULL;
|
|
bs->drv = NULL;
|
|
bs->copy_on_read = 0;
|
|
bs->backing_file[0] = '\0';
|
|
bs->backing_format[0] = '\0';
|
|
bs->total_sectors = 0;
|
|
bs->encrypted = 0;
|
|
bs->valid_key = 0;
|
|
bs->sg = 0;
|
|
bs->zero_beyond_eof = false;
|
|
QDECREF(bs->options);
|
|
bs->options = NULL;
|
|
QDECREF(bs->full_open_options);
|
|
bs->full_open_options = NULL;
|
|
|
|
if (bs->file != NULL) {
|
|
bdrv_unref(bs->file);
|
|
bs->file = NULL;
|
|
}
|
|
}
|
|
|
|
if (bs->blk) {
|
|
blk_dev_change_media_cb(bs->blk, false);
|
|
}
|
|
|
|
/*throttling disk I/O limits*/
|
|
if (bs->io_limits_enabled) {
|
|
bdrv_io_limits_disable(bs);
|
|
}
|
|
|
|
QLIST_FOREACH_SAFE(ban, &bs->aio_notifiers, list, ban_next) {
|
|
g_free(ban);
|
|
}
|
|
QLIST_INIT(&bs->aio_notifiers);
|
|
}
|
|
|
|
void bdrv_close_all(void)
|
|
{
|
|
BlockDriverState *bs;
|
|
|
|
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
|
AioContext *aio_context = bdrv_get_aio_context(bs);
|
|
|
|
aio_context_acquire(aio_context);
|
|
bdrv_close(bs);
|
|
aio_context_release(aio_context);
|
|
}
|
|
}
|
|
|
|
/* make a BlockDriverState anonymous by removing from bdrv_state and
|
|
* graph_bdrv_state list.
|
|
Also, NULL terminate the device_name to prevent double remove */
|
|
void bdrv_make_anon(BlockDriverState *bs)
|
|
{
|
|
/*
|
|
* Take care to remove bs from bdrv_states only when it's actually
|
|
* in it. Note that bs->device_list.tqe_prev is initially null,
|
|
* and gets set to non-null by QTAILQ_INSERT_TAIL(). Establish
|
|
* the useful invariant "bs in bdrv_states iff bs->tqe_prev" by
|
|
* resetting it to null on remove.
|
|
*/
|
|
if (bs->device_list.tqe_prev) {
|
|
QTAILQ_REMOVE(&bdrv_states, bs, device_list);
|
|
bs->device_list.tqe_prev = NULL;
|
|
}
|
|
if (bs->node_name[0] != '\0') {
|
|
QTAILQ_REMOVE(&graph_bdrv_states, bs, node_list);
|
|
}
|
|
bs->node_name[0] = '\0';
|
|
}
|
|
|
|
static void bdrv_rebind(BlockDriverState *bs)
|
|
{
|
|
if (bs->drv && bs->drv->bdrv_rebind) {
|
|
bs->drv->bdrv_rebind(bs);
|
|
}
|
|
}
|
|
|
|
static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
|
|
BlockDriverState *bs_src)
|
|
{
|
|
/* move some fields that need to stay attached to the device */
|
|
|
|
/* dev info */
|
|
bs_dest->guest_block_size = bs_src->guest_block_size;
|
|
bs_dest->copy_on_read = bs_src->copy_on_read;
|
|
|
|
bs_dest->enable_write_cache = bs_src->enable_write_cache;
|
|
|
|
/* i/o throttled req */
|
|
memcpy(&bs_dest->throttle_state,
|
|
&bs_src->throttle_state,
|
|
sizeof(ThrottleState));
|
|
bs_dest->throttled_reqs[0] = bs_src->throttled_reqs[0];
|
|
bs_dest->throttled_reqs[1] = bs_src->throttled_reqs[1];
|
|
bs_dest->io_limits_enabled = bs_src->io_limits_enabled;
|
|
|
|
/* r/w error */
|
|
bs_dest->on_read_error = bs_src->on_read_error;
|
|
bs_dest->on_write_error = bs_src->on_write_error;
|
|
|
|
/* i/o status */
|
|
bs_dest->iostatus_enabled = bs_src->iostatus_enabled;
|
|
bs_dest->iostatus = bs_src->iostatus;
|
|
|
|
/* dirty bitmap */
|
|
bs_dest->dirty_bitmaps = bs_src->dirty_bitmaps;
|
|
|
|
/* reference count */
|
|
bs_dest->refcnt = bs_src->refcnt;
|
|
|
|
/* job */
|
|
bs_dest->job = bs_src->job;
|
|
|
|
/* keep the same entry in bdrv_states */
|
|
bs_dest->device_list = bs_src->device_list;
|
|
bs_dest->blk = bs_src->blk;
|
|
|
|
memcpy(bs_dest->op_blockers, bs_src->op_blockers,
|
|
sizeof(bs_dest->op_blockers));
|
|
}
|
|
|
|
/*
|
|
* Swap bs contents for two image chains while they are live,
|
|
* while keeping required fields on the BlockDriverState that is
|
|
* actually attached to a device.
|
|
*
|
|
* This will modify the BlockDriverState fields, and swap contents
|
|
* between bs_new and bs_old. Both bs_new and bs_old are modified.
|
|
*
|
|
* bs_new must not be attached to a BlockBackend.
|
|
*
|
|
* This function does not create any image files.
|
|
*/
|
|
void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
|
|
{
|
|
BlockDriverState tmp;
|
|
|
|
/* The code needs to swap the node_name but simply swapping node_list won't
|
|
* work so first remove the nodes from the graph list, do the swap then
|
|
* insert them back if needed.
|
|
*/
|
|
if (bs_new->node_name[0] != '\0') {
|
|
QTAILQ_REMOVE(&graph_bdrv_states, bs_new, node_list);
|
|
}
|
|
if (bs_old->node_name[0] != '\0') {
|
|
QTAILQ_REMOVE(&graph_bdrv_states, bs_old, node_list);
|
|
}
|
|
|
|
/* bs_new must be unattached and shouldn't have anything fancy enabled */
|
|
assert(!bs_new->blk);
|
|
assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
|
|
assert(bs_new->job == NULL);
|
|
assert(bs_new->io_limits_enabled == false);
|
|
assert(!throttle_have_timer(&bs_new->throttle_state));
|
|
|
|
tmp = *bs_new;
|
|
*bs_new = *bs_old;
|
|
*bs_old = tmp;
|
|
|
|
/* there are some fields that should not be swapped, move them back */
|
|
bdrv_move_feature_fields(&tmp, bs_old);
|
|
bdrv_move_feature_fields(bs_old, bs_new);
|
|
bdrv_move_feature_fields(bs_new, &tmp);
|
|
|
|
/* bs_new must remain unattached */
|
|
assert(!bs_new->blk);
|
|
|
|
/* Check a few fields that should remain attached to the device */
|
|
assert(bs_new->job == NULL);
|
|
assert(bs_new->io_limits_enabled == false);
|
|
assert(!throttle_have_timer(&bs_new->throttle_state));
|
|
|
|
/* insert the nodes back into the graph node list if needed */
|
|
if (bs_new->node_name[0] != '\0') {
|
|
QTAILQ_INSERT_TAIL(&graph_bdrv_states, bs_new, node_list);
|
|
}
|
|
if (bs_old->node_name[0] != '\0') {
|
|
QTAILQ_INSERT_TAIL(&graph_bdrv_states, bs_old, node_list);
|
|
}
|
|
|
|
bdrv_rebind(bs_new);
|
|
bdrv_rebind(bs_old);
|
|
}
|
|
|
|
/*
|
|
* Add new bs contents at the top of an image chain while the chain is
|
|
* live, while keeping required fields on the top layer.
|
|
*
|
|
* This will modify the BlockDriverState fields, and swap contents
|
|
* between bs_new and bs_top. Both bs_new and bs_top are modified.
|
|
*
|
|
* bs_new must not be attached to a BlockBackend.
|
|
*
|
|
* This function does not create any image files.
|
|
*/
|
|
void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top)
|
|
{
|
|
bdrv_swap(bs_new, bs_top);
|
|
|
|
/* The contents of 'tmp' will become bs_top, as we are
|
|
* swapping bs_new and bs_top contents. */
|
|
bdrv_set_backing_hd(bs_top, bs_new);
|
|
}
|
|
|
|
static void bdrv_delete(BlockDriverState *bs)
|
|
{
|
|
assert(!bs->job);
|
|
assert(bdrv_op_blocker_is_empty(bs));
|
|
assert(!bs->refcnt);
|
|
assert(QLIST_EMPTY(&bs->dirty_bitmaps));
|
|
|
|
bdrv_close(bs);
|
|
|
|
/* remove from list, if necessary */
|
|
bdrv_make_anon(bs);
|
|
|
|
g_free(bs);
|
|
}
|
|
|
|
/*
|
|
* Run consistency checks on an image
|
|
*
|
|
* Returns 0 if the check could be completed (it doesn't mean that the image is
|
|
* free of errors) or -errno when an internal error occurred. The results of the
|
|
* check are stored in res.
|
|
*/
|
|
int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix)
|
|
{
|
|
if (bs->drv == NULL) {
|
|
return -ENOMEDIUM;
|
|
}
|
|
if (bs->drv->bdrv_check == NULL) {
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
memset(res, 0, sizeof(*res));
|
|
return bs->drv->bdrv_check(bs, res, fix);
|
|
}
|
|
|
|
#define COMMIT_BUF_SECTORS 2048
|
|
|
|
/* commit COW file into the raw image */
|
|
int bdrv_commit(BlockDriverState *bs)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
int64_t sector, total_sectors, length, backing_length;
|
|
int n, ro, open_flags;
|
|
int ret = 0;
|
|
uint8_t *buf = NULL;
|
|
|
|
if (!drv)
|
|
return -ENOMEDIUM;
|
|
|
|
if (!bs->backing_hd) {
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT_SOURCE, NULL) ||
|
|
bdrv_op_is_blocked(bs->backing_hd, BLOCK_OP_TYPE_COMMIT_TARGET, NULL)) {
|
|
return -EBUSY;
|
|
}
|
|
|
|
ro = bs->backing_hd->read_only;
|
|
open_flags = bs->backing_hd->open_flags;
|
|
|
|
if (ro) {
|
|
if (bdrv_reopen(bs->backing_hd, open_flags | BDRV_O_RDWR, NULL)) {
|
|
return -EACCES;
|
|
}
|
|
}
|
|
|
|
length = bdrv_getlength(bs);
|
|
if (length < 0) {
|
|
ret = length;
|
|
goto ro_cleanup;
|
|
}
|
|
|
|
backing_length = bdrv_getlength(bs->backing_hd);
|
|
if (backing_length < 0) {
|
|
ret = backing_length;
|
|
goto ro_cleanup;
|
|
}
|
|
|
|
/* If our top snapshot is larger than the backing file image,
|
|
* grow the backing file image if possible. If not possible,
|
|
* we must return an error */
|
|
if (length > backing_length) {
|
|
ret = bdrv_truncate(bs->backing_hd, length);
|
|
if (ret < 0) {
|
|
goto ro_cleanup;
|
|
}
|
|
}
|
|
|
|
total_sectors = length >> BDRV_SECTOR_BITS;
|
|
|
|
/* qemu_try_blockalign() for bs will choose an alignment that works for
|
|
* bs->backing_hd as well, so no need to compare the alignment manually. */
|
|
buf = qemu_try_blockalign(bs, COMMIT_BUF_SECTORS * BDRV_SECTOR_SIZE);
|
|
if (buf == NULL) {
|
|
ret = -ENOMEM;
|
|
goto ro_cleanup;
|
|
}
|
|
|
|
for (sector = 0; sector < total_sectors; sector += n) {
|
|
ret = bdrv_is_allocated(bs, sector, COMMIT_BUF_SECTORS, &n);
|
|
if (ret < 0) {
|
|
goto ro_cleanup;
|
|
}
|
|
if (ret) {
|
|
ret = bdrv_read(bs, sector, buf, n);
|
|
if (ret < 0) {
|
|
goto ro_cleanup;
|
|
}
|
|
|
|
ret = bdrv_write(bs->backing_hd, sector, buf, n);
|
|
if (ret < 0) {
|
|
goto ro_cleanup;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (drv->bdrv_make_empty) {
|
|
ret = drv->bdrv_make_empty(bs);
|
|
if (ret < 0) {
|
|
goto ro_cleanup;
|
|
}
|
|
bdrv_flush(bs);
|
|
}
|
|
|
|
/*
|
|
* Make sure all data we wrote to the backing device is actually
|
|
* stable on disk.
|
|
*/
|
|
if (bs->backing_hd) {
|
|
bdrv_flush(bs->backing_hd);
|
|
}
|
|
|
|
ret = 0;
|
|
ro_cleanup:
|
|
qemu_vfree(buf);
|
|
|
|
if (ro) {
|
|
/* ignoring error return here */
|
|
bdrv_reopen(bs->backing_hd, open_flags & ~BDRV_O_RDWR, NULL);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
int bdrv_commit_all(void)
|
|
{
|
|
BlockDriverState *bs;
|
|
|
|
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
|
AioContext *aio_context = bdrv_get_aio_context(bs);
|
|
|
|
aio_context_acquire(aio_context);
|
|
if (bs->drv && bs->backing_hd) {
|
|
int ret = bdrv_commit(bs);
|
|
if (ret < 0) {
|
|
aio_context_release(aio_context);
|
|
return ret;
|
|
}
|
|
}
|
|
aio_context_release(aio_context);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Return values:
|
|
* 0 - success
|
|
* -EINVAL - backing format specified, but no file
|
|
* -ENOSPC - can't update the backing file because no space is left in the
|
|
* image file header
|
|
* -ENOTSUP - format driver doesn't support changing the backing file
|
|
*/
|
|
int bdrv_change_backing_file(BlockDriverState *bs,
|
|
const char *backing_file, const char *backing_fmt)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
int ret;
|
|
|
|
/* Backing file format doesn't make sense without a backing file */
|
|
if (backing_fmt && !backing_file) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (drv->bdrv_change_backing_file != NULL) {
|
|
ret = drv->bdrv_change_backing_file(bs, backing_file, backing_fmt);
|
|
} else {
|
|
ret = -ENOTSUP;
|
|
}
|
|
|
|
if (ret == 0) {
|
|
pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: "");
|
|
pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: "");
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Finds the image layer in the chain that has 'bs' as its backing file.
|
|
*
|
|
* active is the current topmost image.
|
|
*
|
|
* Returns NULL if bs is not found in active's image chain,
|
|
* or if active == bs.
|
|
*
|
|
* Returns the bottommost base image if bs == NULL.
|
|
*/
|
|
BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
|
|
BlockDriverState *bs)
|
|
{
|
|
while (active && bs != active->backing_hd) {
|
|
active = active->backing_hd;
|
|
}
|
|
|
|
return active;
|
|
}
|
|
|
|
/* Given a BDS, searches for the base layer. */
|
|
BlockDriverState *bdrv_find_base(BlockDriverState *bs)
|
|
{
|
|
return bdrv_find_overlay(bs, NULL);
|
|
}
|
|
|
|
typedef struct BlkIntermediateStates {
|
|
BlockDriverState *bs;
|
|
QSIMPLEQ_ENTRY(BlkIntermediateStates) entry;
|
|
} BlkIntermediateStates;
|
|
|
|
|
|
/*
|
|
* Drops images above 'base' up to and including 'top', and sets the image
|
|
* above 'top' to have base as its backing file.
|
|
*
|
|
* Requires that the overlay to 'top' is opened r/w, so that the backing file
|
|
* information in 'bs' can be properly updated.
|
|
*
|
|
* E.g., this will convert the following chain:
|
|
* bottom <- base <- intermediate <- top <- active
|
|
*
|
|
* to
|
|
*
|
|
* bottom <- base <- active
|
|
*
|
|
* It is allowed for bottom==base, in which case it converts:
|
|
*
|
|
* base <- intermediate <- top <- active
|
|
*
|
|
* to
|
|
*
|
|
* base <- active
|
|
*
|
|
* If backing_file_str is non-NULL, it will be used when modifying top's
|
|
* overlay image metadata.
|
|
*
|
|
* Error conditions:
|
|
* if active == top, that is considered an error
|
|
*
|
|
*/
|
|
int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
|
|
BlockDriverState *base, const char *backing_file_str)
|
|
{
|
|
BlockDriverState *intermediate;
|
|
BlockDriverState *base_bs = NULL;
|
|
BlockDriverState *new_top_bs = NULL;
|
|
BlkIntermediateStates *intermediate_state, *next;
|
|
int ret = -EIO;
|
|
|
|
QSIMPLEQ_HEAD(states_to_delete, BlkIntermediateStates) states_to_delete;
|
|
QSIMPLEQ_INIT(&states_to_delete);
|
|
|
|
if (!top->drv || !base->drv) {
|
|
goto exit;
|
|
}
|
|
|
|
new_top_bs = bdrv_find_overlay(active, top);
|
|
|
|
if (new_top_bs == NULL) {
|
|
/* we could not find the image above 'top', this is an error */
|
|
goto exit;
|
|
}
|
|
|
|
/* special case of new_top_bs->backing_hd already pointing to base - nothing
|
|
* to do, no intermediate images */
|
|
if (new_top_bs->backing_hd == base) {
|
|
ret = 0;
|
|
goto exit;
|
|
}
|
|
|
|
intermediate = top;
|
|
|
|
/* now we will go down through the list, and add each BDS we find
|
|
* into our deletion queue, until we hit the 'base'
|
|
*/
|
|
while (intermediate) {
|
|
intermediate_state = g_new0(BlkIntermediateStates, 1);
|
|
intermediate_state->bs = intermediate;
|
|
QSIMPLEQ_INSERT_TAIL(&states_to_delete, intermediate_state, entry);
|
|
|
|
if (intermediate->backing_hd == base) {
|
|
base_bs = intermediate->backing_hd;
|
|
break;
|
|
}
|
|
intermediate = intermediate->backing_hd;
|
|
}
|
|
if (base_bs == NULL) {
|
|
/* something went wrong, we did not end at the base. safely
|
|
* unravel everything, and exit with error */
|
|
goto exit;
|
|
}
|
|
|
|
/* success - we can delete the intermediate states, and link top->base */
|
|
backing_file_str = backing_file_str ? backing_file_str : base_bs->filename;
|
|
ret = bdrv_change_backing_file(new_top_bs, backing_file_str,
|
|
base_bs->drv ? base_bs->drv->format_name : "");
|
|
if (ret) {
|
|
goto exit;
|
|
}
|
|
bdrv_set_backing_hd(new_top_bs, base_bs);
|
|
|
|
QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) {
|
|
/* so that bdrv_close() does not recursively close the chain */
|
|
bdrv_set_backing_hd(intermediate_state->bs, NULL);
|
|
bdrv_unref(intermediate_state->bs);
|
|
}
|
|
ret = 0;
|
|
|
|
exit:
|
|
QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) {
|
|
g_free(intermediate_state);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* Truncate file to 'offset' bytes (needed only for file protocols)
|
|
*/
|
|
int bdrv_truncate(BlockDriverState *bs, int64_t offset)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
int ret;
|
|
if (!drv)
|
|
return -ENOMEDIUM;
|
|
if (!drv->bdrv_truncate)
|
|
return -ENOTSUP;
|
|
if (bs->read_only)
|
|
return -EACCES;
|
|
|
|
ret = drv->bdrv_truncate(bs, offset);
|
|
if (ret == 0) {
|
|
ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
|
|
bdrv_dirty_bitmap_truncate(bs);
|
|
if (bs->blk) {
|
|
blk_dev_resize_cb(bs->blk);
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* Length of a allocated file in bytes. Sparse files are counted by actual
|
|
* allocated space. Return < 0 if error or unknown.
|
|
*/
|
|
int64_t bdrv_get_allocated_file_size(BlockDriverState *bs)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
if (!drv) {
|
|
return -ENOMEDIUM;
|
|
}
|
|
if (drv->bdrv_get_allocated_file_size) {
|
|
return drv->bdrv_get_allocated_file_size(bs);
|
|
}
|
|
if (bs->file) {
|
|
return bdrv_get_allocated_file_size(bs->file);
|
|
}
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
/**
|
|
* Return number of sectors on success, -errno on error.
|
|
*/
|
|
int64_t bdrv_nb_sectors(BlockDriverState *bs)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
|
|
if (!drv)
|
|
return -ENOMEDIUM;
|
|
|
|
if (drv->has_variable_length) {
|
|
int ret = refresh_total_sectors(bs, bs->total_sectors);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
}
|
|
return bs->total_sectors;
|
|
}
|
|
|
|
/**
|
|
* Return length in bytes on success, -errno on error.
|
|
* The length is always a multiple of BDRV_SECTOR_SIZE.
|
|
*/
|
|
int64_t bdrv_getlength(BlockDriverState *bs)
|
|
{
|
|
int64_t ret = bdrv_nb_sectors(bs);
|
|
|
|
ret = ret > INT64_MAX / BDRV_SECTOR_SIZE ? -EFBIG : ret;
|
|
return ret < 0 ? ret : ret * BDRV_SECTOR_SIZE;
|
|
}
|
|
|
|
/* return 0 as number of sectors if no device present or error */
|
|
void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
|
|
{
|
|
int64_t nb_sectors = bdrv_nb_sectors(bs);
|
|
|
|
*nb_sectors_ptr = nb_sectors < 0 ? 0 : nb_sectors;
|
|
}
|
|
|
|
void bdrv_set_on_error(BlockDriverState *bs, BlockdevOnError on_read_error,
|
|
BlockdevOnError on_write_error)
|
|
{
|
|
bs->on_read_error = on_read_error;
|
|
bs->on_write_error = on_write_error;
|
|
}
|
|
|
|
BlockdevOnError bdrv_get_on_error(BlockDriverState *bs, bool is_read)
|
|
{
|
|
return is_read ? bs->on_read_error : bs->on_write_error;
|
|
}
|
|
|
|
BlockErrorAction bdrv_get_error_action(BlockDriverState *bs, bool is_read, int error)
|
|
{
|
|
BlockdevOnError on_err = is_read ? bs->on_read_error : bs->on_write_error;
|
|
|
|
switch (on_err) {
|
|
case BLOCKDEV_ON_ERROR_ENOSPC:
|
|
return (error == ENOSPC) ?
|
|
BLOCK_ERROR_ACTION_STOP : BLOCK_ERROR_ACTION_REPORT;
|
|
case BLOCKDEV_ON_ERROR_STOP:
|
|
return BLOCK_ERROR_ACTION_STOP;
|
|
case BLOCKDEV_ON_ERROR_REPORT:
|
|
return BLOCK_ERROR_ACTION_REPORT;
|
|
case BLOCKDEV_ON_ERROR_IGNORE:
|
|
return BLOCK_ERROR_ACTION_IGNORE;
|
|
default:
|
|
abort();
|
|
}
|
|
}
|
|
|
|
static void send_qmp_error_event(BlockDriverState *bs,
|
|
BlockErrorAction action,
|
|
bool is_read, int error)
|
|
{
|
|
IoOperationType optype;
|
|
|
|
optype = is_read ? IO_OPERATION_TYPE_READ : IO_OPERATION_TYPE_WRITE;
|
|
qapi_event_send_block_io_error(bdrv_get_device_name(bs), optype, action,
|
|
bdrv_iostatus_is_enabled(bs),
|
|
error == ENOSPC, strerror(error),
|
|
&error_abort);
|
|
}
|
|
|
|
/* This is done by device models because, while the block layer knows
|
|
* about the error, it does not know whether an operation comes from
|
|
* the device or the block layer (from a job, for example).
|
|
*/
|
|
void bdrv_error_action(BlockDriverState *bs, BlockErrorAction action,
|
|
bool is_read, int error)
|
|
{
|
|
assert(error >= 0);
|
|
|
|
if (action == BLOCK_ERROR_ACTION_STOP) {
|
|
/* First set the iostatus, so that "info block" returns an iostatus
|
|
* that matches the events raised so far (an additional error iostatus
|
|
* is fine, but not a lost one).
|
|
*/
|
|
bdrv_iostatus_set_err(bs, error);
|
|
|
|
/* Then raise the request to stop the VM and the event.
|
|
* qemu_system_vmstop_request_prepare has two effects. First,
|
|
* it ensures that the STOP event always comes after the
|
|
* BLOCK_IO_ERROR event. Second, it ensures that even if management
|
|
* can observe the STOP event and do a "cont" before the STOP
|
|
* event is issued, the VM will not stop. In this case, vm_start()
|
|
* also ensures that the STOP/RESUME pair of events is emitted.
|
|
*/
|
|
qemu_system_vmstop_request_prepare();
|
|
send_qmp_error_event(bs, action, is_read, error);
|
|
qemu_system_vmstop_request(RUN_STATE_IO_ERROR);
|
|
} else {
|
|
send_qmp_error_event(bs, action, is_read, error);
|
|
}
|
|
}
|
|
|
|
int bdrv_is_read_only(BlockDriverState *bs)
|
|
{
|
|
return bs->read_only;
|
|
}
|
|
|
|
int bdrv_is_sg(BlockDriverState *bs)
|
|
{
|
|
return bs->sg;
|
|
}
|
|
|
|
int bdrv_enable_write_cache(BlockDriverState *bs)
|
|
{
|
|
return bs->enable_write_cache;
|
|
}
|
|
|
|
void bdrv_set_enable_write_cache(BlockDriverState *bs, bool wce)
|
|
{
|
|
bs->enable_write_cache = wce;
|
|
|
|
/* so a reopen() will preserve wce */
|
|
if (wce) {
|
|
bs->open_flags |= BDRV_O_CACHE_WB;
|
|
} else {
|
|
bs->open_flags &= ~BDRV_O_CACHE_WB;
|
|
}
|
|
}
|
|
|
|
int bdrv_is_encrypted(BlockDriverState *bs)
|
|
{
|
|
if (bs->backing_hd && bs->backing_hd->encrypted)
|
|
return 1;
|
|
return bs->encrypted;
|
|
}
|
|
|
|
int bdrv_key_required(BlockDriverState *bs)
|
|
{
|
|
BlockDriverState *backing_hd = bs->backing_hd;
|
|
|
|
if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key)
|
|
return 1;
|
|
return (bs->encrypted && !bs->valid_key);
|
|
}
|
|
|
|
int bdrv_set_key(BlockDriverState *bs, const char *key)
|
|
{
|
|
int ret;
|
|
if (bs->backing_hd && bs->backing_hd->encrypted) {
|
|
ret = bdrv_set_key(bs->backing_hd, key);
|
|
if (ret < 0)
|
|
return ret;
|
|
if (!bs->encrypted)
|
|
return 0;
|
|
}
|
|
if (!bs->encrypted) {
|
|
return -EINVAL;
|
|
} else if (!bs->drv || !bs->drv->bdrv_set_key) {
|
|
return -ENOMEDIUM;
|
|
}
|
|
ret = bs->drv->bdrv_set_key(bs, key);
|
|
if (ret < 0) {
|
|
bs->valid_key = 0;
|
|
} else if (!bs->valid_key) {
|
|
bs->valid_key = 1;
|
|
if (bs->blk) {
|
|
/* call the change callback now, we skipped it on open */
|
|
blk_dev_change_media_cb(bs->blk, true);
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Provide an encryption key for @bs.
|
|
* If @key is non-null:
|
|
* If @bs is not encrypted, fail.
|
|
* Else if the key is invalid, fail.
|
|
* Else set @bs's key to @key, replacing the existing key, if any.
|
|
* If @key is null:
|
|
* If @bs is encrypted and still lacks a key, fail.
|
|
* Else do nothing.
|
|
* On failure, store an error object through @errp if non-null.
|
|
*/
|
|
void bdrv_add_key(BlockDriverState *bs, const char *key, Error **errp)
|
|
{
|
|
if (key) {
|
|
if (!bdrv_is_encrypted(bs)) {
|
|
error_setg(errp, "Node '%s' is not encrypted",
|
|
bdrv_get_device_or_node_name(bs));
|
|
} else if (bdrv_set_key(bs, key) < 0) {
|
|
error_set(errp, QERR_INVALID_PASSWORD);
|
|
}
|
|
} else {
|
|
if (bdrv_key_required(bs)) {
|
|
error_set(errp, ERROR_CLASS_DEVICE_ENCRYPTED,
|
|
"'%s' (%s) is encrypted",
|
|
bdrv_get_device_or_node_name(bs),
|
|
bdrv_get_encrypted_filename(bs));
|
|
}
|
|
}
|
|
}
|
|
|
|
const char *bdrv_get_format_name(BlockDriverState *bs)
|
|
{
|
|
return bs->drv ? bs->drv->format_name : NULL;
|
|
}
|
|
|
|
static int qsort_strcmp(const void *a, const void *b)
|
|
{
|
|
return strcmp(a, b);
|
|
}
|
|
|
|
void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
|
|
void *opaque)
|
|
{
|
|
BlockDriver *drv;
|
|
int count = 0;
|
|
int i;
|
|
const char **formats = NULL;
|
|
|
|
QLIST_FOREACH(drv, &bdrv_drivers, list) {
|
|
if (drv->format_name) {
|
|
bool found = false;
|
|
int i = count;
|
|
while (formats && i && !found) {
|
|
found = !strcmp(formats[--i], drv->format_name);
|
|
}
|
|
|
|
if (!found) {
|
|
formats = g_renew(const char *, formats, count + 1);
|
|
formats[count++] = drv->format_name;
|
|
}
|
|
}
|
|
}
|
|
|
|
qsort(formats, count, sizeof(formats[0]), qsort_strcmp);
|
|
|
|
for (i = 0; i < count; i++) {
|
|
it(opaque, formats[i]);
|
|
}
|
|
|
|
g_free(formats);
|
|
}
|
|
|
|
/* This function is to find a node in the bs graph */
|
|
BlockDriverState *bdrv_find_node(const char *node_name)
|
|
{
|
|
BlockDriverState *bs;
|
|
|
|
assert(node_name);
|
|
|
|
QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) {
|
|
if (!strcmp(node_name, bs->node_name)) {
|
|
return bs;
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/* Put this QMP function here so it can access the static graph_bdrv_states. */
|
|
BlockDeviceInfoList *bdrv_named_nodes_list(Error **errp)
|
|
{
|
|
BlockDeviceInfoList *list, *entry;
|
|
BlockDriverState *bs;
|
|
|
|
list = NULL;
|
|
QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) {
|
|
BlockDeviceInfo *info = bdrv_block_device_info(bs, errp);
|
|
if (!info) {
|
|
qapi_free_BlockDeviceInfoList(list);
|
|
return NULL;
|
|
}
|
|
entry = g_malloc0(sizeof(*entry));
|
|
entry->value = info;
|
|
entry->next = list;
|
|
list = entry;
|
|
}
|
|
|
|
return list;
|
|
}
|
|
|
|
BlockDriverState *bdrv_lookup_bs(const char *device,
|
|
const char *node_name,
|
|
Error **errp)
|
|
{
|
|
BlockBackend *blk;
|
|
BlockDriverState *bs;
|
|
|
|
if (device) {
|
|
blk = blk_by_name(device);
|
|
|
|
if (blk) {
|
|
return blk_bs(blk);
|
|
}
|
|
}
|
|
|
|
if (node_name) {
|
|
bs = bdrv_find_node(node_name);
|
|
|
|
if (bs) {
|
|
return bs;
|
|
}
|
|
}
|
|
|
|
error_setg(errp, "Cannot find device=%s nor node_name=%s",
|
|
device ? device : "",
|
|
node_name ? node_name : "");
|
|
return NULL;
|
|
}
|
|
|
|
/* If 'base' is in the same chain as 'top', return true. Otherwise,
|
|
* return false. If either argument is NULL, return false. */
|
|
bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base)
|
|
{
|
|
while (top && top != base) {
|
|
top = top->backing_hd;
|
|
}
|
|
|
|
return top != NULL;
|
|
}
|
|
|
|
BlockDriverState *bdrv_next_node(BlockDriverState *bs)
|
|
{
|
|
if (!bs) {
|
|
return QTAILQ_FIRST(&graph_bdrv_states);
|
|
}
|
|
return QTAILQ_NEXT(bs, node_list);
|
|
}
|
|
|
|
BlockDriverState *bdrv_next(BlockDriverState *bs)
|
|
{
|
|
if (!bs) {
|
|
return QTAILQ_FIRST(&bdrv_states);
|
|
}
|
|
return QTAILQ_NEXT(bs, device_list);
|
|
}
|
|
|
|
const char *bdrv_get_node_name(const BlockDriverState *bs)
|
|
{
|
|
return bs->node_name;
|
|
}
|
|
|
|
/* TODO check what callers really want: bs->node_name or blk_name() */
|
|
const char *bdrv_get_device_name(const BlockDriverState *bs)
|
|
{
|
|
return bs->blk ? blk_name(bs->blk) : "";
|
|
}
|
|
|
|
/* This can be used to identify nodes that might not have a device
|
|
* name associated. Since node and device names live in the same
|
|
* namespace, the result is unambiguous. The exception is if both are
|
|
* absent, then this returns an empty (non-null) string. */
|
|
const char *bdrv_get_device_or_node_name(const BlockDriverState *bs)
|
|
{
|
|
return bs->blk ? blk_name(bs->blk) : bs->node_name;
|
|
}
|
|
|
|
int bdrv_get_flags(BlockDriverState *bs)
|
|
{
|
|
return bs->open_flags;
|
|
}
|
|
|
|
int bdrv_has_zero_init_1(BlockDriverState *bs)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
int bdrv_has_zero_init(BlockDriverState *bs)
|
|
{
|
|
assert(bs->drv);
|
|
|
|
/* If BS is a copy on write image, it is initialized to
|
|
the contents of the base image, which may not be zeroes. */
|
|
if (bs->backing_hd) {
|
|
return 0;
|
|
}
|
|
if (bs->drv->bdrv_has_zero_init) {
|
|
return bs->drv->bdrv_has_zero_init(bs);
|
|
}
|
|
|
|
/* safe default */
|
|
return 0;
|
|
}
|
|
|
|
bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs)
|
|
{
|
|
BlockDriverInfo bdi;
|
|
|
|
if (bs->backing_hd) {
|
|
return false;
|
|
}
|
|
|
|
if (bdrv_get_info(bs, &bdi) == 0) {
|
|
return bdi.unallocated_blocks_are_zero;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs)
|
|
{
|
|
BlockDriverInfo bdi;
|
|
|
|
if (bs->backing_hd || !(bs->open_flags & BDRV_O_UNMAP)) {
|
|
return false;
|
|
}
|
|
|
|
if (bdrv_get_info(bs, &bdi) == 0) {
|
|
return bdi.can_write_zeroes_with_unmap;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
const char *bdrv_get_encrypted_filename(BlockDriverState *bs)
|
|
{
|
|
if (bs->backing_hd && bs->backing_hd->encrypted)
|
|
return bs->backing_file;
|
|
else if (bs->encrypted)
|
|
return bs->filename;
|
|
else
|
|
return NULL;
|
|
}
|
|
|
|
void bdrv_get_backing_filename(BlockDriverState *bs,
|
|
char *filename, int filename_size)
|
|
{
|
|
pstrcpy(filename, filename_size, bs->backing_file);
|
|
}
|
|
|
|
int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
if (!drv)
|
|
return -ENOMEDIUM;
|
|
if (!drv->bdrv_get_info)
|
|
return -ENOTSUP;
|
|
memset(bdi, 0, sizeof(*bdi));
|
|
return drv->bdrv_get_info(bs, bdi);
|
|
}
|
|
|
|
ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
if (drv && drv->bdrv_get_specific_info) {
|
|
return drv->bdrv_get_specific_info(bs);
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event)
|
|
{
|
|
if (!bs || !bs->drv || !bs->drv->bdrv_debug_event) {
|
|
return;
|
|
}
|
|
|
|
bs->drv->bdrv_debug_event(bs, event);
|
|
}
|
|
|
|
int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
|
|
const char *tag)
|
|
{
|
|
while (bs && bs->drv && !bs->drv->bdrv_debug_breakpoint) {
|
|
bs = bs->file;
|
|
}
|
|
|
|
if (bs && bs->drv && bs->drv->bdrv_debug_breakpoint) {
|
|
return bs->drv->bdrv_debug_breakpoint(bs, event, tag);
|
|
}
|
|
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag)
|
|
{
|
|
while (bs && bs->drv && !bs->drv->bdrv_debug_remove_breakpoint) {
|
|
bs = bs->file;
|
|
}
|
|
|
|
if (bs && bs->drv && bs->drv->bdrv_debug_remove_breakpoint) {
|
|
return bs->drv->bdrv_debug_remove_breakpoint(bs, tag);
|
|
}
|
|
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
int bdrv_debug_resume(BlockDriverState *bs, const char *tag)
|
|
{
|
|
while (bs && (!bs->drv || !bs->drv->bdrv_debug_resume)) {
|
|
bs = bs->file;
|
|
}
|
|
|
|
if (bs && bs->drv && bs->drv->bdrv_debug_resume) {
|
|
return bs->drv->bdrv_debug_resume(bs, tag);
|
|
}
|
|
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag)
|
|
{
|
|
while (bs && bs->drv && !bs->drv->bdrv_debug_is_suspended) {
|
|
bs = bs->file;
|
|
}
|
|
|
|
if (bs && bs->drv && bs->drv->bdrv_debug_is_suspended) {
|
|
return bs->drv->bdrv_debug_is_suspended(bs, tag);
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
int bdrv_is_snapshot(BlockDriverState *bs)
|
|
{
|
|
return !!(bs->open_flags & BDRV_O_SNAPSHOT);
|
|
}
|
|
|
|
/* backing_file can either be relative, or absolute, or a protocol. If it is
|
|
* relative, it must be relative to the chain. So, passing in bs->filename
|
|
* from a BDS as backing_file should not be done, as that may be relative to
|
|
* the CWD rather than the chain. */
|
|
BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs,
|
|
const char *backing_file)
|
|
{
|
|
char *filename_full = NULL;
|
|
char *backing_file_full = NULL;
|
|
char *filename_tmp = NULL;
|
|
int is_protocol = 0;
|
|
BlockDriverState *curr_bs = NULL;
|
|
BlockDriverState *retval = NULL;
|
|
|
|
if (!bs || !bs->drv || !backing_file) {
|
|
return NULL;
|
|
}
|
|
|
|
filename_full = g_malloc(PATH_MAX);
|
|
backing_file_full = g_malloc(PATH_MAX);
|
|
filename_tmp = g_malloc(PATH_MAX);
|
|
|
|
is_protocol = path_has_protocol(backing_file);
|
|
|
|
for (curr_bs = bs; curr_bs->backing_hd; curr_bs = curr_bs->backing_hd) {
|
|
|
|
/* If either of the filename paths is actually a protocol, then
|
|
* compare unmodified paths; otherwise make paths relative */
|
|
if (is_protocol || path_has_protocol(curr_bs->backing_file)) {
|
|
if (strcmp(backing_file, curr_bs->backing_file) == 0) {
|
|
retval = curr_bs->backing_hd;
|
|
break;
|
|
}
|
|
} else {
|
|
/* If not an absolute filename path, make it relative to the current
|
|
* image's filename path */
|
|
path_combine(filename_tmp, PATH_MAX, curr_bs->filename,
|
|
backing_file);
|
|
|
|
/* We are going to compare absolute pathnames */
|
|
if (!realpath(filename_tmp, filename_full)) {
|
|
continue;
|
|
}
|
|
|
|
/* We need to make sure the backing filename we are comparing against
|
|
* is relative to the current image filename (or absolute) */
|
|
path_combine(filename_tmp, PATH_MAX, curr_bs->filename,
|
|
curr_bs->backing_file);
|
|
|
|
if (!realpath(filename_tmp, backing_file_full)) {
|
|
continue;
|
|
}
|
|
|
|
if (strcmp(backing_file_full, filename_full) == 0) {
|
|
retval = curr_bs->backing_hd;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
g_free(filename_full);
|
|
g_free(backing_file_full);
|
|
g_free(filename_tmp);
|
|
return retval;
|
|
}
|
|
|
|
int bdrv_get_backing_file_depth(BlockDriverState *bs)
|
|
{
|
|
if (!bs->drv) {
|
|
return 0;
|
|
}
|
|
|
|
if (!bs->backing_hd) {
|
|
return 0;
|
|
}
|
|
|
|
return 1 + bdrv_get_backing_file_depth(bs->backing_hd);
|
|
}
|
|
|
|
void bdrv_init(void)
|
|
{
|
|
module_call_init(MODULE_INIT_BLOCK);
|
|
}
|
|
|
|
void bdrv_init_with_whitelist(void)
|
|
{
|
|
use_bdrv_whitelist = 1;
|
|
bdrv_init();
|
|
}
|
|
|
|
void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp)
|
|
{
|
|
Error *local_err = NULL;
|
|
int ret;
|
|
|
|
if (!bs->drv) {
|
|
return;
|
|
}
|
|
|
|
if (!(bs->open_flags & BDRV_O_INCOMING)) {
|
|
return;
|
|
}
|
|
bs->open_flags &= ~BDRV_O_INCOMING;
|
|
|
|
if (bs->drv->bdrv_invalidate_cache) {
|
|
bs->drv->bdrv_invalidate_cache(bs, &local_err);
|
|
} else if (bs->file) {
|
|
bdrv_invalidate_cache(bs->file, &local_err);
|
|
}
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
return;
|
|
}
|
|
|
|
ret = refresh_total_sectors(bs, bs->total_sectors);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Could not refresh total sector count");
|
|
return;
|
|
}
|
|
}
|
|
|
|
void bdrv_invalidate_cache_all(Error **errp)
|
|
{
|
|
BlockDriverState *bs;
|
|
Error *local_err = NULL;
|
|
|
|
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
|
AioContext *aio_context = bdrv_get_aio_context(bs);
|
|
|
|
aio_context_acquire(aio_context);
|
|
bdrv_invalidate_cache(bs, &local_err);
|
|
aio_context_release(aio_context);
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
/**************************************************************/
|
|
/* removable device support */
|
|
|
|
/**
|
|
* Return TRUE if the media is present
|
|
*/
|
|
int bdrv_is_inserted(BlockDriverState *bs)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
|
|
if (!drv)
|
|
return 0;
|
|
if (!drv->bdrv_is_inserted)
|
|
return 1;
|
|
return drv->bdrv_is_inserted(bs);
|
|
}
|
|
|
|
/**
|
|
* Return whether the media changed since the last call to this
|
|
* function, or -ENOTSUP if we don't know. Most drivers don't know.
|
|
*/
|
|
int bdrv_media_changed(BlockDriverState *bs)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
|
|
if (drv && drv->bdrv_media_changed) {
|
|
return drv->bdrv_media_changed(bs);
|
|
}
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
/**
|
|
* If eject_flag is TRUE, eject the media. Otherwise, close the tray
|
|
*/
|
|
void bdrv_eject(BlockDriverState *bs, bool eject_flag)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
const char *device_name;
|
|
|
|
if (drv && drv->bdrv_eject) {
|
|
drv->bdrv_eject(bs, eject_flag);
|
|
}
|
|
|
|
device_name = bdrv_get_device_name(bs);
|
|
if (device_name[0] != '\0') {
|
|
qapi_event_send_device_tray_moved(device_name,
|
|
eject_flag, &error_abort);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Lock or unlock the media (if it is locked, the user won't be able
|
|
* to eject it manually).
|
|
*/
|
|
void bdrv_lock_medium(BlockDriverState *bs, bool locked)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
|
|
trace_bdrv_lock_medium(bs, locked);
|
|
|
|
if (drv && drv->bdrv_lock_medium) {
|
|
drv->bdrv_lock_medium(bs, locked);
|
|
}
|
|
}
|
|
|
|
void bdrv_set_guest_block_size(BlockDriverState *bs, int align)
|
|
{
|
|
bs->guest_block_size = align;
|
|
}
|
|
|
|
BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs, const char *name)
|
|
{
|
|
BdrvDirtyBitmap *bm;
|
|
|
|
assert(name);
|
|
QLIST_FOREACH(bm, &bs->dirty_bitmaps, list) {
|
|
if (bm->name && !strcmp(name, bm->name)) {
|
|
return bm;
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
void bdrv_dirty_bitmap_make_anon(BdrvDirtyBitmap *bitmap)
|
|
{
|
|
assert(!bdrv_dirty_bitmap_frozen(bitmap));
|
|
g_free(bitmap->name);
|
|
bitmap->name = NULL;
|
|
}
|
|
|
|
BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
|
|
uint32_t granularity,
|
|
const char *name,
|
|
Error **errp)
|
|
{
|
|
int64_t bitmap_size;
|
|
BdrvDirtyBitmap *bitmap;
|
|
uint32_t sector_granularity;
|
|
|
|
assert((granularity & (granularity - 1)) == 0);
|
|
|
|
if (name && bdrv_find_dirty_bitmap(bs, name)) {
|
|
error_setg(errp, "Bitmap already exists: %s", name);
|
|
return NULL;
|
|
}
|
|
sector_granularity = granularity >> BDRV_SECTOR_BITS;
|
|
assert(sector_granularity);
|
|
bitmap_size = bdrv_nb_sectors(bs);
|
|
if (bitmap_size < 0) {
|
|
error_setg_errno(errp, -bitmap_size, "could not get length of device");
|
|
errno = -bitmap_size;
|
|
return NULL;
|
|
}
|
|
bitmap = g_new0(BdrvDirtyBitmap, 1);
|
|
bitmap->bitmap = hbitmap_alloc(bitmap_size, ctz32(sector_granularity));
|
|
bitmap->size = bitmap_size;
|
|
bitmap->name = g_strdup(name);
|
|
bitmap->disabled = false;
|
|
QLIST_INSERT_HEAD(&bs->dirty_bitmaps, bitmap, list);
|
|
return bitmap;
|
|
}
|
|
|
|
bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap)
|
|
{
|
|
return bitmap->successor;
|
|
}
|
|
|
|
bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap)
|
|
{
|
|
return !(bitmap->disabled || bitmap->successor);
|
|
}
|
|
|
|
DirtyBitmapStatus bdrv_dirty_bitmap_status(BdrvDirtyBitmap *bitmap)
|
|
{
|
|
if (bdrv_dirty_bitmap_frozen(bitmap)) {
|
|
return DIRTY_BITMAP_STATUS_FROZEN;
|
|
} else if (!bdrv_dirty_bitmap_enabled(bitmap)) {
|
|
return DIRTY_BITMAP_STATUS_DISABLED;
|
|
} else {
|
|
return DIRTY_BITMAP_STATUS_ACTIVE;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Create a successor bitmap destined to replace this bitmap after an operation.
|
|
* Requires that the bitmap is not frozen and has no successor.
|
|
*/
|
|
int bdrv_dirty_bitmap_create_successor(BlockDriverState *bs,
|
|
BdrvDirtyBitmap *bitmap, Error **errp)
|
|
{
|
|
uint64_t granularity;
|
|
BdrvDirtyBitmap *child;
|
|
|
|
if (bdrv_dirty_bitmap_frozen(bitmap)) {
|
|
error_setg(errp, "Cannot create a successor for a bitmap that is "
|
|
"currently frozen");
|
|
return -1;
|
|
}
|
|
assert(!bitmap->successor);
|
|
|
|
/* Create an anonymous successor */
|
|
granularity = bdrv_dirty_bitmap_granularity(bitmap);
|
|
child = bdrv_create_dirty_bitmap(bs, granularity, NULL, errp);
|
|
if (!child) {
|
|
return -1;
|
|
}
|
|
|
|
/* Successor will be on or off based on our current state. */
|
|
child->disabled = bitmap->disabled;
|
|
|
|
/* Install the successor and freeze the parent */
|
|
bitmap->successor = child;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* For a bitmap with a successor, yield our name to the successor,
|
|
* delete the old bitmap, and return a handle to the new bitmap.
|
|
*/
|
|
BdrvDirtyBitmap *bdrv_dirty_bitmap_abdicate(BlockDriverState *bs,
|
|
BdrvDirtyBitmap *bitmap,
|
|
Error **errp)
|
|
{
|
|
char *name;
|
|
BdrvDirtyBitmap *successor = bitmap->successor;
|
|
|
|
if (successor == NULL) {
|
|
error_setg(errp, "Cannot relinquish control if "
|
|
"there's no successor present");
|
|
return NULL;
|
|
}
|
|
|
|
name = bitmap->name;
|
|
bitmap->name = NULL;
|
|
successor->name = name;
|
|
bitmap->successor = NULL;
|
|
bdrv_release_dirty_bitmap(bs, bitmap);
|
|
|
|
return successor;
|
|
}
|
|
|
|
/**
|
|
* In cases of failure where we can no longer safely delete the parent,
|
|
* we may wish to re-join the parent and child/successor.
|
|
* The merged parent will be un-frozen, but not explicitly re-enabled.
|
|
*/
|
|
BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
|
|
BdrvDirtyBitmap *parent,
|
|
Error **errp)
|
|
{
|
|
BdrvDirtyBitmap *successor = parent->successor;
|
|
|
|
if (!successor) {
|
|
error_setg(errp, "Cannot reclaim a successor when none is present");
|
|
return NULL;
|
|
}
|
|
|
|
if (!hbitmap_merge(parent->bitmap, successor->bitmap)) {
|
|
error_setg(errp, "Merging of parent and successor bitmap failed");
|
|
return NULL;
|
|
}
|
|
bdrv_release_dirty_bitmap(bs, successor);
|
|
parent->successor = NULL;
|
|
|
|
return parent;
|
|
}
|
|
|
|
/**
|
|
* Truncates _all_ bitmaps attached to a BDS.
|
|
*/
|
|
static void bdrv_dirty_bitmap_truncate(BlockDriverState *bs)
|
|
{
|
|
BdrvDirtyBitmap *bitmap;
|
|
uint64_t size = bdrv_nb_sectors(bs);
|
|
|
|
QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
|
|
assert(!bdrv_dirty_bitmap_frozen(bitmap));
|
|
hbitmap_truncate(bitmap->bitmap, size);
|
|
bitmap->size = size;
|
|
}
|
|
}
|
|
|
|
void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
|
|
{
|
|
BdrvDirtyBitmap *bm, *next;
|
|
QLIST_FOREACH_SAFE(bm, &bs->dirty_bitmaps, list, next) {
|
|
if (bm == bitmap) {
|
|
assert(!bdrv_dirty_bitmap_frozen(bm));
|
|
QLIST_REMOVE(bitmap, list);
|
|
hbitmap_free(bitmap->bitmap);
|
|
g_free(bitmap->name);
|
|
g_free(bitmap);
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
void bdrv_disable_dirty_bitmap(BdrvDirtyBitmap *bitmap)
|
|
{
|
|
assert(!bdrv_dirty_bitmap_frozen(bitmap));
|
|
bitmap->disabled = true;
|
|
}
|
|
|
|
void bdrv_enable_dirty_bitmap(BdrvDirtyBitmap *bitmap)
|
|
{
|
|
assert(!bdrv_dirty_bitmap_frozen(bitmap));
|
|
bitmap->disabled = false;
|
|
}
|
|
|
|
BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
|
|
{
|
|
BdrvDirtyBitmap *bm;
|
|
BlockDirtyInfoList *list = NULL;
|
|
BlockDirtyInfoList **plist = &list;
|
|
|
|
QLIST_FOREACH(bm, &bs->dirty_bitmaps, list) {
|
|
BlockDirtyInfo *info = g_new0(BlockDirtyInfo, 1);
|
|
BlockDirtyInfoList *entry = g_new0(BlockDirtyInfoList, 1);
|
|
info->count = bdrv_get_dirty_count(bm);
|
|
info->granularity = bdrv_dirty_bitmap_granularity(bm);
|
|
info->has_name = !!bm->name;
|
|
info->name = g_strdup(bm->name);
|
|
info->status = bdrv_dirty_bitmap_status(bm);
|
|
entry->value = info;
|
|
*plist = entry;
|
|
plist = &entry->next;
|
|
}
|
|
|
|
return list;
|
|
}
|
|
|
|
int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector)
|
|
{
|
|
if (bitmap) {
|
|
return hbitmap_get(bitmap->bitmap, sector);
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Chooses a default granularity based on the existing cluster size,
|
|
* but clamped between [4K, 64K]. Defaults to 64K in the case that there
|
|
* is no cluster size information available.
|
|
*/
|
|
uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs)
|
|
{
|
|
BlockDriverInfo bdi;
|
|
uint32_t granularity;
|
|
|
|
if (bdrv_get_info(bs, &bdi) >= 0 && bdi.cluster_size > 0) {
|
|
granularity = MAX(4096, bdi.cluster_size);
|
|
granularity = MIN(65536, granularity);
|
|
} else {
|
|
granularity = 65536;
|
|
}
|
|
|
|
return granularity;
|
|
}
|
|
|
|
uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap)
|
|
{
|
|
return BDRV_SECTOR_SIZE << hbitmap_granularity(bitmap->bitmap);
|
|
}
|
|
|
|
void bdrv_dirty_iter_init(BdrvDirtyBitmap *bitmap, HBitmapIter *hbi)
|
|
{
|
|
hbitmap_iter_init(hbi, bitmap->bitmap, 0);
|
|
}
|
|
|
|
void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
|
|
int64_t cur_sector, int nr_sectors)
|
|
{
|
|
assert(bdrv_dirty_bitmap_enabled(bitmap));
|
|
hbitmap_set(bitmap->bitmap, cur_sector, nr_sectors);
|
|
}
|
|
|
|
void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
|
|
int64_t cur_sector, int nr_sectors)
|
|
{
|
|
assert(bdrv_dirty_bitmap_enabled(bitmap));
|
|
hbitmap_reset(bitmap->bitmap, cur_sector, nr_sectors);
|
|
}
|
|
|
|
void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap)
|
|
{
|
|
assert(bdrv_dirty_bitmap_enabled(bitmap));
|
|
hbitmap_reset(bitmap->bitmap, 0, bitmap->size);
|
|
}
|
|
|
|
void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector,
|
|
int nr_sectors)
|
|
{
|
|
BdrvDirtyBitmap *bitmap;
|
|
QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
|
|
if (!bdrv_dirty_bitmap_enabled(bitmap)) {
|
|
continue;
|
|
}
|
|
hbitmap_set(bitmap->bitmap, cur_sector, nr_sectors);
|
|
}
|
|
}
|
|
|
|
void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector,
|
|
int nr_sectors)
|
|
{
|
|
BdrvDirtyBitmap *bitmap;
|
|
QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
|
|
if (!bdrv_dirty_bitmap_enabled(bitmap)) {
|
|
continue;
|
|
}
|
|
hbitmap_reset(bitmap->bitmap, cur_sector, nr_sectors);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Advance an HBitmapIter to an arbitrary offset.
|
|
*/
|
|
void bdrv_set_dirty_iter(HBitmapIter *hbi, int64_t offset)
|
|
{
|
|
assert(hbi->hb);
|
|
hbitmap_iter_init(hbi, hbi->hb, offset);
|
|
}
|
|
|
|
int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap)
|
|
{
|
|
return hbitmap_count(bitmap->bitmap);
|
|
}
|
|
|
|
/* Get a reference to bs */
|
|
void bdrv_ref(BlockDriverState *bs)
|
|
{
|
|
bs->refcnt++;
|
|
}
|
|
|
|
/* Release a previously grabbed reference to bs.
|
|
* If after releasing, reference count is zero, the BlockDriverState is
|
|
* deleted. */
|
|
void bdrv_unref(BlockDriverState *bs)
|
|
{
|
|
if (!bs) {
|
|
return;
|
|
}
|
|
assert(bs->refcnt > 0);
|
|
if (--bs->refcnt == 0) {
|
|
bdrv_delete(bs);
|
|
}
|
|
}
|
|
|
|
struct BdrvOpBlocker {
|
|
Error *reason;
|
|
QLIST_ENTRY(BdrvOpBlocker) list;
|
|
};
|
|
|
|
bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp)
|
|
{
|
|
BdrvOpBlocker *blocker;
|
|
assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX);
|
|
if (!QLIST_EMPTY(&bs->op_blockers[op])) {
|
|
blocker = QLIST_FIRST(&bs->op_blockers[op]);
|
|
if (errp) {
|
|
error_setg(errp, "Node '%s' is busy: %s",
|
|
bdrv_get_device_or_node_name(bs),
|
|
error_get_pretty(blocker->reason));
|
|
}
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason)
|
|
{
|
|
BdrvOpBlocker *blocker;
|
|
assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX);
|
|
|
|
blocker = g_new0(BdrvOpBlocker, 1);
|
|
blocker->reason = reason;
|
|
QLIST_INSERT_HEAD(&bs->op_blockers[op], blocker, list);
|
|
}
|
|
|
|
void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason)
|
|
{
|
|
BdrvOpBlocker *blocker, *next;
|
|
assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX);
|
|
QLIST_FOREACH_SAFE(blocker, &bs->op_blockers[op], list, next) {
|
|
if (blocker->reason == reason) {
|
|
QLIST_REMOVE(blocker, list);
|
|
g_free(blocker);
|
|
}
|
|
}
|
|
}
|
|
|
|
void bdrv_op_block_all(BlockDriverState *bs, Error *reason)
|
|
{
|
|
int i;
|
|
for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) {
|
|
bdrv_op_block(bs, i, reason);
|
|
}
|
|
}
|
|
|
|
void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason)
|
|
{
|
|
int i;
|
|
for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) {
|
|
bdrv_op_unblock(bs, i, reason);
|
|
}
|
|
}
|
|
|
|
bool bdrv_op_blocker_is_empty(BlockDriverState *bs)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) {
|
|
if (!QLIST_EMPTY(&bs->op_blockers[i])) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
void bdrv_iostatus_enable(BlockDriverState *bs)
|
|
{
|
|
bs->iostatus_enabled = true;
|
|
bs->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
|
|
}
|
|
|
|
/* The I/O status is only enabled if the drive explicitly
|
|
* enables it _and_ the VM is configured to stop on errors */
|
|
bool bdrv_iostatus_is_enabled(const BlockDriverState *bs)
|
|
{
|
|
return (bs->iostatus_enabled &&
|
|
(bs->on_write_error == BLOCKDEV_ON_ERROR_ENOSPC ||
|
|
bs->on_write_error == BLOCKDEV_ON_ERROR_STOP ||
|
|
bs->on_read_error == BLOCKDEV_ON_ERROR_STOP));
|
|
}
|
|
|
|
void bdrv_iostatus_disable(BlockDriverState *bs)
|
|
{
|
|
bs->iostatus_enabled = false;
|
|
}
|
|
|
|
void bdrv_iostatus_reset(BlockDriverState *bs)
|
|
{
|
|
if (bdrv_iostatus_is_enabled(bs)) {
|
|
bs->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
|
|
if (bs->job) {
|
|
block_job_iostatus_reset(bs->job);
|
|
}
|
|
}
|
|
}
|
|
|
|
void bdrv_iostatus_set_err(BlockDriverState *bs, int error)
|
|
{
|
|
assert(bdrv_iostatus_is_enabled(bs));
|
|
if (bs->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
|
|
bs->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE :
|
|
BLOCK_DEVICE_IO_STATUS_FAILED;
|
|
}
|
|
}
|
|
|
|
void bdrv_img_create(const char *filename, const char *fmt,
|
|
const char *base_filename, const char *base_fmt,
|
|
char *options, uint64_t img_size, int flags,
|
|
Error **errp, bool quiet)
|
|
{
|
|
QemuOptsList *create_opts = NULL;
|
|
QemuOpts *opts = NULL;
|
|
const char *backing_fmt, *backing_file;
|
|
int64_t size;
|
|
BlockDriver *drv, *proto_drv;
|
|
BlockDriver *backing_drv = NULL;
|
|
Error *local_err = NULL;
|
|
int ret = 0;
|
|
|
|
/* Find driver and parse its options */
|
|
drv = bdrv_find_format(fmt);
|
|
if (!drv) {
|
|
error_setg(errp, "Unknown file format '%s'", fmt);
|
|
return;
|
|
}
|
|
|
|
proto_drv = bdrv_find_protocol(filename, true, errp);
|
|
if (!proto_drv) {
|
|
return;
|
|
}
|
|
|
|
if (!drv->create_opts) {
|
|
error_setg(errp, "Format driver '%s' does not support image creation",
|
|
drv->format_name);
|
|
return;
|
|
}
|
|
|
|
if (!proto_drv->create_opts) {
|
|
error_setg(errp, "Protocol driver '%s' does not support image creation",
|
|
proto_drv->format_name);
|
|
return;
|
|
}
|
|
|
|
create_opts = qemu_opts_append(create_opts, drv->create_opts);
|
|
create_opts = qemu_opts_append(create_opts, proto_drv->create_opts);
|
|
|
|
/* Create parameter list with default values */
|
|
opts = qemu_opts_create(create_opts, NULL, 0, &error_abort);
|
|
qemu_opt_set_number(opts, BLOCK_OPT_SIZE, img_size, &error_abort);
|
|
|
|
/* Parse -o options */
|
|
if (options) {
|
|
qemu_opts_do_parse(opts, options, NULL, &local_err);
|
|
if (local_err) {
|
|
error_report_err(local_err);
|
|
local_err = NULL;
|
|
error_setg(errp, "Invalid options for file format '%s'", fmt);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (base_filename) {
|
|
qemu_opt_set(opts, BLOCK_OPT_BACKING_FILE, base_filename, &local_err);
|
|
if (local_err) {
|
|
error_setg(errp, "Backing file not supported for file format '%s'",
|
|
fmt);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (base_fmt) {
|
|
qemu_opt_set(opts, BLOCK_OPT_BACKING_FMT, base_fmt, &local_err);
|
|
if (local_err) {
|
|
error_setg(errp, "Backing file format not supported for file "
|
|
"format '%s'", fmt);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
backing_file = qemu_opt_get(opts, BLOCK_OPT_BACKING_FILE);
|
|
if (backing_file) {
|
|
if (!strcmp(filename, backing_file)) {
|
|
error_setg(errp, "Error: Trying to create an image with the "
|
|
"same filename as the backing file");
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
backing_fmt = qemu_opt_get(opts, BLOCK_OPT_BACKING_FMT);
|
|
if (backing_fmt) {
|
|
backing_drv = bdrv_find_format(backing_fmt);
|
|
if (!backing_drv) {
|
|
error_setg(errp, "Unknown backing file format '%s'",
|
|
backing_fmt);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
// The size for the image must always be specified, with one exception:
|
|
// If we are using a backing file, we can obtain the size from there
|
|
size = qemu_opt_get_size(opts, BLOCK_OPT_SIZE, 0);
|
|
if (size == -1) {
|
|
if (backing_file) {
|
|
BlockDriverState *bs;
|
|
char *full_backing = g_new0(char, PATH_MAX);
|
|
int64_t size;
|
|
int back_flags;
|
|
|
|
bdrv_get_full_backing_filename_from_filename(filename, backing_file,
|
|
full_backing, PATH_MAX,
|
|
&local_err);
|
|
if (local_err) {
|
|
g_free(full_backing);
|
|
goto out;
|
|
}
|
|
|
|
/* backing files always opened read-only */
|
|
back_flags =
|
|
flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
|
|
|
|
bs = NULL;
|
|
ret = bdrv_open(&bs, full_backing, NULL, NULL, back_flags,
|
|
backing_drv, &local_err);
|
|
g_free(full_backing);
|
|
if (ret < 0) {
|
|
goto out;
|
|
}
|
|
size = bdrv_getlength(bs);
|
|
if (size < 0) {
|
|
error_setg_errno(errp, -size, "Could not get size of '%s'",
|
|
backing_file);
|
|
bdrv_unref(bs);
|
|
goto out;
|
|
}
|
|
|
|
qemu_opt_set_number(opts, BLOCK_OPT_SIZE, size, &error_abort);
|
|
|
|
bdrv_unref(bs);
|
|
} else {
|
|
error_setg(errp, "Image creation needs a size parameter");
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (!quiet) {
|
|
printf("Formatting '%s', fmt=%s", filename, fmt);
|
|
qemu_opts_print(opts, " ");
|
|
puts("");
|
|
}
|
|
|
|
ret = bdrv_create(drv, filename, opts, &local_err);
|
|
|
|
if (ret == -EFBIG) {
|
|
/* This is generally a better message than whatever the driver would
|
|
* deliver (especially because of the cluster_size_hint), since that
|
|
* is most probably not much different from "image too large". */
|
|
const char *cluster_size_hint = "";
|
|
if (qemu_opt_get_size(opts, BLOCK_OPT_CLUSTER_SIZE, 0)) {
|
|
cluster_size_hint = " (try using a larger cluster size)";
|
|
}
|
|
error_setg(errp, "The image size is too large for file format '%s'"
|
|
"%s", fmt, cluster_size_hint);
|
|
error_free(local_err);
|
|
local_err = NULL;
|
|
}
|
|
|
|
out:
|
|
qemu_opts_del(opts);
|
|
qemu_opts_free(create_opts);
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
}
|
|
}
|
|
|
|
AioContext *bdrv_get_aio_context(BlockDriverState *bs)
|
|
{
|
|
return bs->aio_context;
|
|
}
|
|
|
|
void bdrv_detach_aio_context(BlockDriverState *bs)
|
|
{
|
|
BdrvAioNotifier *baf;
|
|
|
|
if (!bs->drv) {
|
|
return;
|
|
}
|
|
|
|
QLIST_FOREACH(baf, &bs->aio_notifiers, list) {
|
|
baf->detach_aio_context(baf->opaque);
|
|
}
|
|
|
|
if (bs->io_limits_enabled) {
|
|
throttle_detach_aio_context(&bs->throttle_state);
|
|
}
|
|
if (bs->drv->bdrv_detach_aio_context) {
|
|
bs->drv->bdrv_detach_aio_context(bs);
|
|
}
|
|
if (bs->file) {
|
|
bdrv_detach_aio_context(bs->file);
|
|
}
|
|
if (bs->backing_hd) {
|
|
bdrv_detach_aio_context(bs->backing_hd);
|
|
}
|
|
|
|
bs->aio_context = NULL;
|
|
}
|
|
|
|
void bdrv_attach_aio_context(BlockDriverState *bs,
|
|
AioContext *new_context)
|
|
{
|
|
BdrvAioNotifier *ban;
|
|
|
|
if (!bs->drv) {
|
|
return;
|
|
}
|
|
|
|
bs->aio_context = new_context;
|
|
|
|
if (bs->backing_hd) {
|
|
bdrv_attach_aio_context(bs->backing_hd, new_context);
|
|
}
|
|
if (bs->file) {
|
|
bdrv_attach_aio_context(bs->file, new_context);
|
|
}
|
|
if (bs->drv->bdrv_attach_aio_context) {
|
|
bs->drv->bdrv_attach_aio_context(bs, new_context);
|
|
}
|
|
if (bs->io_limits_enabled) {
|
|
throttle_attach_aio_context(&bs->throttle_state, new_context);
|
|
}
|
|
|
|
QLIST_FOREACH(ban, &bs->aio_notifiers, list) {
|
|
ban->attached_aio_context(new_context, ban->opaque);
|
|
}
|
|
}
|
|
|
|
void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context)
|
|
{
|
|
bdrv_drain_all(); /* ensure there are no in-flight requests */
|
|
|
|
bdrv_detach_aio_context(bs);
|
|
|
|
/* This function executes in the old AioContext so acquire the new one in
|
|
* case it runs in a different thread.
|
|
*/
|
|
aio_context_acquire(new_context);
|
|
bdrv_attach_aio_context(bs, new_context);
|
|
aio_context_release(new_context);
|
|
}
|
|
|
|
void bdrv_add_aio_context_notifier(BlockDriverState *bs,
|
|
void (*attached_aio_context)(AioContext *new_context, void *opaque),
|
|
void (*detach_aio_context)(void *opaque), void *opaque)
|
|
{
|
|
BdrvAioNotifier *ban = g_new(BdrvAioNotifier, 1);
|
|
*ban = (BdrvAioNotifier){
|
|
.attached_aio_context = attached_aio_context,
|
|
.detach_aio_context = detach_aio_context,
|
|
.opaque = opaque
|
|
};
|
|
|
|
QLIST_INSERT_HEAD(&bs->aio_notifiers, ban, list);
|
|
}
|
|
|
|
void bdrv_remove_aio_context_notifier(BlockDriverState *bs,
|
|
void (*attached_aio_context)(AioContext *,
|
|
void *),
|
|
void (*detach_aio_context)(void *),
|
|
void *opaque)
|
|
{
|
|
BdrvAioNotifier *ban, *ban_next;
|
|
|
|
QLIST_FOREACH_SAFE(ban, &bs->aio_notifiers, list, ban_next) {
|
|
if (ban->attached_aio_context == attached_aio_context &&
|
|
ban->detach_aio_context == detach_aio_context &&
|
|
ban->opaque == opaque)
|
|
{
|
|
QLIST_REMOVE(ban, list);
|
|
g_free(ban);
|
|
|
|
return;
|
|
}
|
|
}
|
|
|
|
abort();
|
|
}
|
|
|
|
int bdrv_amend_options(BlockDriverState *bs, QemuOpts *opts,
|
|
BlockDriverAmendStatusCB *status_cb)
|
|
{
|
|
if (!bs->drv->bdrv_amend_options) {
|
|
return -ENOTSUP;
|
|
}
|
|
return bs->drv->bdrv_amend_options(bs, opts, status_cb);
|
|
}
|
|
|
|
/* This function will be called by the bdrv_recurse_is_first_non_filter method
|
|
* of block filter and by bdrv_is_first_non_filter.
|
|
* It is used to test if the given bs is the candidate or recurse more in the
|
|
* node graph.
|
|
*/
|
|
bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs,
|
|
BlockDriverState *candidate)
|
|
{
|
|
/* return false if basic checks fails */
|
|
if (!bs || !bs->drv) {
|
|
return false;
|
|
}
|
|
|
|
/* the code reached a non block filter driver -> check if the bs is
|
|
* the same as the candidate. It's the recursion termination condition.
|
|
*/
|
|
if (!bs->drv->is_filter) {
|
|
return bs == candidate;
|
|
}
|
|
/* Down this path the driver is a block filter driver */
|
|
|
|
/* If the block filter recursion method is defined use it to recurse down
|
|
* the node graph.
|
|
*/
|
|
if (bs->drv->bdrv_recurse_is_first_non_filter) {
|
|
return bs->drv->bdrv_recurse_is_first_non_filter(bs, candidate);
|
|
}
|
|
|
|
/* the driver is a block filter but don't allow to recurse -> return false
|
|
*/
|
|
return false;
|
|
}
|
|
|
|
/* This function checks if the candidate is the first non filter bs down it's
|
|
* bs chain. Since we don't have pointers to parents it explore all bs chains
|
|
* from the top. Some filters can choose not to pass down the recursion.
|
|
*/
|
|
bool bdrv_is_first_non_filter(BlockDriverState *candidate)
|
|
{
|
|
BlockDriverState *bs;
|
|
|
|
/* walk down the bs forest recursively */
|
|
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
|
bool perm;
|
|
|
|
/* try to recurse in this top level bs */
|
|
perm = bdrv_recurse_is_first_non_filter(bs, candidate);
|
|
|
|
/* candidate is the first non filter */
|
|
if (perm) {
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
BlockDriverState *check_to_replace_node(const char *node_name, Error **errp)
|
|
{
|
|
BlockDriverState *to_replace_bs = bdrv_find_node(node_name);
|
|
AioContext *aio_context;
|
|
|
|
if (!to_replace_bs) {
|
|
error_setg(errp, "Node name '%s' not found", node_name);
|
|
return NULL;
|
|
}
|
|
|
|
aio_context = bdrv_get_aio_context(to_replace_bs);
|
|
aio_context_acquire(aio_context);
|
|
|
|
if (bdrv_op_is_blocked(to_replace_bs, BLOCK_OP_TYPE_REPLACE, errp)) {
|
|
to_replace_bs = NULL;
|
|
goto out;
|
|
}
|
|
|
|
/* We don't want arbitrary node of the BDS chain to be replaced only the top
|
|
* most non filter in order to prevent data corruption.
|
|
* Another benefit is that this tests exclude backing files which are
|
|
* blocked by the backing blockers.
|
|
*/
|
|
if (!bdrv_is_first_non_filter(to_replace_bs)) {
|
|
error_setg(errp, "Only top most non filter can be replaced");
|
|
to_replace_bs = NULL;
|
|
goto out;
|
|
}
|
|
|
|
out:
|
|
aio_context_release(aio_context);
|
|
return to_replace_bs;
|
|
}
|
|
|
|
static bool append_open_options(QDict *d, BlockDriverState *bs)
|
|
{
|
|
const QDictEntry *entry;
|
|
bool found_any = false;
|
|
|
|
for (entry = qdict_first(bs->options); entry;
|
|
entry = qdict_next(bs->options, entry))
|
|
{
|
|
/* Only take options for this level and exclude all non-driver-specific
|
|
* options */
|
|
if (!strchr(qdict_entry_key(entry), '.') &&
|
|
strcmp(qdict_entry_key(entry), "node-name"))
|
|
{
|
|
qobject_incref(qdict_entry_value(entry));
|
|
qdict_put_obj(d, qdict_entry_key(entry), qdict_entry_value(entry));
|
|
found_any = true;
|
|
}
|
|
}
|
|
|
|
return found_any;
|
|
}
|
|
|
|
/* Updates the following BDS fields:
|
|
* - exact_filename: A filename which may be used for opening a block device
|
|
* which (mostly) equals the given BDS (even without any
|
|
* other options; so reading and writing must return the same
|
|
* results, but caching etc. may be different)
|
|
* - full_open_options: Options which, when given when opening a block device
|
|
* (without a filename), result in a BDS (mostly)
|
|
* equalling the given one
|
|
* - filename: If exact_filename is set, it is copied here. Otherwise,
|
|
* full_open_options is converted to a JSON object, prefixed with
|
|
* "json:" (for use through the JSON pseudo protocol) and put here.
|
|
*/
|
|
void bdrv_refresh_filename(BlockDriverState *bs)
|
|
{
|
|
BlockDriver *drv = bs->drv;
|
|
QDict *opts;
|
|
|
|
if (!drv) {
|
|
return;
|
|
}
|
|
|
|
/* This BDS's file name will most probably depend on its file's name, so
|
|
* refresh that first */
|
|
if (bs->file) {
|
|
bdrv_refresh_filename(bs->file);
|
|
}
|
|
|
|
if (drv->bdrv_refresh_filename) {
|
|
/* Obsolete information is of no use here, so drop the old file name
|
|
* information before refreshing it */
|
|
bs->exact_filename[0] = '\0';
|
|
if (bs->full_open_options) {
|
|
QDECREF(bs->full_open_options);
|
|
bs->full_open_options = NULL;
|
|
}
|
|
|
|
drv->bdrv_refresh_filename(bs);
|
|
} else if (bs->file) {
|
|
/* Try to reconstruct valid information from the underlying file */
|
|
bool has_open_options;
|
|
|
|
bs->exact_filename[0] = '\0';
|
|
if (bs->full_open_options) {
|
|
QDECREF(bs->full_open_options);
|
|
bs->full_open_options = NULL;
|
|
}
|
|
|
|
opts = qdict_new();
|
|
has_open_options = append_open_options(opts, bs);
|
|
|
|
/* If no specific options have been given for this BDS, the filename of
|
|
* the underlying file should suffice for this one as well */
|
|
if (bs->file->exact_filename[0] && !has_open_options) {
|
|
strcpy(bs->exact_filename, bs->file->exact_filename);
|
|
}
|
|
/* Reconstructing the full options QDict is simple for most format block
|
|
* drivers, as long as the full options are known for the underlying
|
|
* file BDS. The full options QDict of that file BDS should somehow
|
|
* contain a representation of the filename, therefore the following
|
|
* suffices without querying the (exact_)filename of this BDS. */
|
|
if (bs->file->full_open_options) {
|
|
qdict_put_obj(opts, "driver",
|
|
QOBJECT(qstring_from_str(drv->format_name)));
|
|
QINCREF(bs->file->full_open_options);
|
|
qdict_put_obj(opts, "file", QOBJECT(bs->file->full_open_options));
|
|
|
|
bs->full_open_options = opts;
|
|
} else {
|
|
QDECREF(opts);
|
|
}
|
|
} else if (!bs->full_open_options && qdict_size(bs->options)) {
|
|
/* There is no underlying file BDS (at least referenced by BDS.file),
|
|
* so the full options QDict should be equal to the options given
|
|
* specifically for this block device when it was opened (plus the
|
|
* driver specification).
|
|
* Because those options don't change, there is no need to update
|
|
* full_open_options when it's already set. */
|
|
|
|
opts = qdict_new();
|
|
append_open_options(opts, bs);
|
|
qdict_put_obj(opts, "driver",
|
|
QOBJECT(qstring_from_str(drv->format_name)));
|
|
|
|
if (bs->exact_filename[0]) {
|
|
/* This may not work for all block protocol drivers (some may
|
|
* require this filename to be parsed), but we have to find some
|
|
* default solution here, so just include it. If some block driver
|
|
* does not support pure options without any filename at all or
|
|
* needs some special format of the options QDict, it needs to
|
|
* implement the driver-specific bdrv_refresh_filename() function.
|
|
*/
|
|
qdict_put_obj(opts, "filename",
|
|
QOBJECT(qstring_from_str(bs->exact_filename)));
|
|
}
|
|
|
|
bs->full_open_options = opts;
|
|
}
|
|
|
|
if (bs->exact_filename[0]) {
|
|
pstrcpy(bs->filename, sizeof(bs->filename), bs->exact_filename);
|
|
} else if (bs->full_open_options) {
|
|
QString *json = qobject_to_json(QOBJECT(bs->full_open_options));
|
|
snprintf(bs->filename, sizeof(bs->filename), "json:%s",
|
|
qstring_get_str(json));
|
|
QDECREF(json);
|
|
}
|
|
}
|
|
|
|
/* This accessor function purpose is to allow the device models to access the
|
|
* BlockAcctStats structure embedded inside a BlockDriverState without being
|
|
* aware of the BlockDriverState structure layout.
|
|
* It will go away when the BlockAcctStats structure will be moved inside
|
|
* the device models.
|
|
*/
|
|
BlockAcctStats *bdrv_get_stats(BlockDriverState *bs)
|
|
{
|
|
return &bs->stats;
|
|
}
|