--- /dev/null
+/*
+ * Write logging blk driver based on blkverify and blkdebug.
+ *
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qemu/sockets.h" /* for EINPROGRESS on Windows */
+#include "block/block_int.h"
+#include "qapi/qmp/qdict.h"
+#include "qapi/qmp/qstring.h"
+#include "qemu/cutils.h"
+#include "qemu/option.h"
+
+/* Disk format stuff - taken from Linux drivers/md/dm-log-writes.c */
+
+#define LOG_FLUSH_FLAG (1 << 0)
+#define LOG_FUA_FLAG (1 << 1)
+#define LOG_DISCARD_FLAG (1 << 2)
+#define LOG_MARK_FLAG (1 << 3)
+
+#define WRITE_LOG_VERSION 1ULL
+#define WRITE_LOG_MAGIC 0x6a736677736872ULL
+
+/* All fields are little-endian. */
+struct log_write_super {
+ uint64_t magic;
+ uint64_t version;
+ uint64_t nr_entries;
+ uint32_t sectorsize;
+} QEMU_PACKED;
+
+struct log_write_entry {
+ uint64_t sector;
+ uint64_t nr_sectors;
+ uint64_t flags;
+ uint64_t data_len;
+} QEMU_PACKED;
+
+/* End of disk format structures. */
+
+typedef struct {
+ BdrvChild *log_file;
+ uint32_t sectorsize;
+ uint32_t sectorbits;
+ uint64_t cur_log_sector;
+ uint64_t nr_entries;
+} BDRVBlkLogWritesState;
+
+static QemuOptsList runtime_opts = {
+ .name = "blklogwrites",
+ .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
+ .desc = {
+ {
+ .name = "log-sector-size",
+ .type = QEMU_OPT_SIZE,
+ .help = "Log sector size",
+ },
+ { /* end of list */ }
+ },
+};
+
+static inline uint32_t blk_log_writes_log2(uint32_t value)
+{
+ assert(value > 0);
+ return 31 - clz32(value);
+}
+
+static int blk_log_writes_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
+{
+ BDRVBlkLogWritesState *s = bs->opaque;
+ QemuOpts *opts;
+ Error *local_err = NULL;
+ int ret;
+ int64_t log_sector_size;
+
+ opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
+ qemu_opts_absorb_qdict(opts, options, &local_err);
+ if (local_err) {
+ ret = -EINVAL;
+ error_propagate(errp, local_err);
+ goto fail;
+ }
+
+ /* Open the file */
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, false,
+ &local_err);
+ if (local_err) {
+ ret = -EINVAL;
+ error_propagate(errp, local_err);
+ goto fail;
+ }
+
+ log_sector_size = qemu_opt_get_size(opts, "log-sector-size",
+ BDRV_SECTOR_SIZE);
+
+ if (log_sector_size < 0 || log_sector_size > (1ull << 23) ||
+ !is_power_of_2(log_sector_size))
+ {
+ ret = -EINVAL;
+ error_setg(errp, "Invalid log sector size %"PRId64, log_sector_size);
+ goto fail;
+ }
+
+ s->sectorsize = log_sector_size;
+ s->sectorbits = blk_log_writes_log2(log_sector_size);
+ s->cur_log_sector = 1;
+ s->nr_entries = 0;
+
+ /* Open the log file */
+ s->log_file = bdrv_open_child(NULL, options, "log", bs, &child_file, false,
+ &local_err);
+ if (local_err) {
+ ret = -EINVAL;
+ error_propagate(errp, local_err);
+ goto fail;
+ }
+
+ ret = 0;
+fail:
+ if (ret < 0) {
+ bdrv_unref_child(bs, bs->file);
+ bs->file = NULL;
+ }
+ qemu_opts_del(opts);
+ return ret;
+}
+
+static void blk_log_writes_close(BlockDriverState *bs)
+{
+ BDRVBlkLogWritesState *s = bs->opaque;
+
+ bdrv_unref_child(bs, s->log_file);
+ s->log_file = NULL;
+}
+
+static int64_t blk_log_writes_getlength(BlockDriverState *bs)
+{
+ return bdrv_getlength(bs->file->bs);
+}
+
+static void blk_log_writes_refresh_filename(BlockDriverState *bs,
+ QDict *options)
+{
+ BDRVBlkLogWritesState *s = bs->opaque;
+
+ /* bs->file->bs has already been refreshed */
+ bdrv_refresh_filename(s->log_file->bs);
+
+ if (bs->file->bs->full_open_options
+ && s->log_file->bs->full_open_options)
+ {
+ QDict *opts = qdict_new();
+ qdict_put_str(opts, "driver", "blklogwrites");
+
+ qobject_ref(bs->file->bs->full_open_options);
+ qdict_put_obj(opts, "file", QOBJECT(bs->file->bs->full_open_options));
+ qobject_ref(s->log_file->bs->full_open_options);
+ qdict_put_obj(opts, "log",
+ QOBJECT(s->log_file->bs->full_open_options));
+ qdict_put_int(opts, "log-sector-size", s->sectorsize);
+
+ bs->full_open_options = opts;
+ }
+}
+
+static void blk_log_writes_child_perm(BlockDriverState *bs, BdrvChild *c,
+ const BdrvChildRole *role,
+ BlockReopenQueue *ro_q,
+ uint64_t perm, uint64_t shrd,
+ uint64_t *nperm, uint64_t *nshrd)
+{
+ if (!c) {
+ *nperm = perm & DEFAULT_PERM_PASSTHROUGH;
+ *nshrd = (shrd & DEFAULT_PERM_PASSTHROUGH) | DEFAULT_PERM_UNCHANGED;
+ return;
+ }
+
+ if (!strcmp(c->name, "log")) {
+ bdrv_format_default_perms(bs, c, role, ro_q, perm, shrd, nperm, nshrd);
+ } else {
+ bdrv_filter_default_perms(bs, c, role, ro_q, perm, shrd, nperm, nshrd);
+ }
+}
+
+static void blk_log_writes_refresh_limits(BlockDriverState *bs, Error **errp)
+{
+ BDRVBlkLogWritesState *s = bs->opaque;
+ bs->bl.request_alignment = s->sectorsize;
+}
+
+static int coroutine_fn
+blk_log_writes_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
+ QEMUIOVector *qiov, int flags)
+{
+ return bdrv_co_preadv(bs->file, offset, bytes, qiov, flags);
+}
+
+typedef struct BlkLogWritesFileReq {
+ BlockDriverState *bs;
+ uint64_t offset;
+ uint64_t bytes;
+ int file_flags;
+ QEMUIOVector *qiov;
+ int (*func)(struct BlkLogWritesFileReq *r);
+ int file_ret;
+} BlkLogWritesFileReq;
+
+typedef struct {
+ BlockDriverState *bs;
+ QEMUIOVector *qiov;
+ struct log_write_entry entry;
+ uint64_t zero_size;
+ int log_ret;
+} BlkLogWritesLogReq;
+
+static void coroutine_fn blk_log_writes_co_do_log(BlkLogWritesLogReq *lr)
+{
+ BDRVBlkLogWritesState *s = lr->bs->opaque;
+ uint64_t cur_log_offset = s->cur_log_sector << s->sectorbits;
+
+ s->nr_entries++;
+ s->cur_log_sector +=
+ ROUND_UP(lr->qiov->size, s->sectorsize) >> s->sectorbits;
+
+ lr->log_ret = bdrv_co_pwritev(s->log_file, cur_log_offset, lr->qiov->size,
+ lr->qiov, 0);
+
+ /* Logging for the "write zeroes" operation */
+ if (lr->log_ret == 0 && lr->zero_size) {
+ cur_log_offset = s->cur_log_sector << s->sectorbits;
+ s->cur_log_sector +=
+ ROUND_UP(lr->zero_size, s->sectorsize) >> s->sectorbits;
+
+ lr->log_ret = bdrv_co_pwrite_zeroes(s->log_file, cur_log_offset,
+ lr->zero_size, 0);
+ }
+
+ /* Update super block on flush */
+ if (lr->log_ret == 0 && lr->entry.flags & LOG_FLUSH_FLAG) {
+ struct log_write_super super = {
+ .magic = cpu_to_le64(WRITE_LOG_MAGIC),
+ .version = cpu_to_le64(WRITE_LOG_VERSION),
+ .nr_entries = cpu_to_le64(s->nr_entries),
+ .sectorsize = cpu_to_le32(s->sectorsize),
+ };
+ void *zeroes = g_malloc0(s->sectorsize - sizeof(super));
+ QEMUIOVector qiov;
+
+ qemu_iovec_init(&qiov, 2);
+ qemu_iovec_add(&qiov, &super, sizeof(super));
+ qemu_iovec_add(&qiov, zeroes, s->sectorsize - sizeof(super));
+
+ lr->log_ret =
+ bdrv_co_pwritev(s->log_file, 0, s->sectorsize, &qiov, 0);
+ if (lr->log_ret == 0) {
+ lr->log_ret = bdrv_co_flush(s->log_file->bs);
+ }
+ qemu_iovec_destroy(&qiov);
+ g_free(zeroes);
+ }
+}
+
+static void coroutine_fn blk_log_writes_co_do_file(BlkLogWritesFileReq *fr)
+{
+ fr->file_ret = fr->func(fr);
+}
+
+static int coroutine_fn
+blk_log_writes_co_log(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
+ QEMUIOVector *qiov, int flags,
+ int (*file_func)(BlkLogWritesFileReq *r),
+ uint64_t entry_flags, bool is_zero_write)
+{
+ QEMUIOVector log_qiov;
+ size_t niov = qiov ? qiov->niov : 0;
+ BDRVBlkLogWritesState *s = bs->opaque;
+ BlkLogWritesFileReq fr = {
+ .bs = bs,
+ .offset = offset,
+ .bytes = bytes,
+ .file_flags = flags,
+ .qiov = qiov,
+ .func = file_func,
+ };
+ BlkLogWritesLogReq lr = {
+ .bs = bs,
+ .qiov = &log_qiov,
+ .entry = {
+ .sector = cpu_to_le64(offset >> s->sectorbits),
+ .nr_sectors = cpu_to_le64(bytes >> s->sectorbits),
+ .flags = cpu_to_le64(entry_flags),
+ .data_len = 0,
+ },
+ .zero_size = is_zero_write ? bytes : 0,
+ };
+ void *zeroes = g_malloc0(s->sectorsize - sizeof(lr.entry));
+
+ assert((1 << s->sectorbits) == s->sectorsize);
+ assert(bs->bl.request_alignment == s->sectorsize);
+ assert(QEMU_IS_ALIGNED(offset, bs->bl.request_alignment));
+ assert(QEMU_IS_ALIGNED(bytes, bs->bl.request_alignment));
+
+ qemu_iovec_init(&log_qiov, niov + 2);
+ qemu_iovec_add(&log_qiov, &lr.entry, sizeof(lr.entry));
+ qemu_iovec_add(&log_qiov, zeroes, s->sectorsize - sizeof(lr.entry));
+ if (qiov) {
+ qemu_iovec_concat(&log_qiov, qiov, 0, qiov->size);
+ }
+
+ blk_log_writes_co_do_file(&fr);
+ blk_log_writes_co_do_log(&lr);
+
+ qemu_iovec_destroy(&log_qiov);
+ g_free(zeroes);
+
+ if (lr.log_ret < 0) {
+ return lr.log_ret;
+ }
+
+ return fr.file_ret;
+}
+
+static int coroutine_fn
+blk_log_writes_co_do_file_pwritev(BlkLogWritesFileReq *fr)
+{
+ return bdrv_co_pwritev(fr->bs->file, fr->offset, fr->bytes,
+ fr->qiov, fr->file_flags);
+}
+
+static int coroutine_fn
+blk_log_writes_co_do_file_pwrite_zeroes(BlkLogWritesFileReq *fr)
+{
+ return bdrv_co_pwrite_zeroes(fr->bs->file, fr->offset, fr->bytes,
+ fr->file_flags);
+}
+
+static int coroutine_fn blk_log_writes_co_do_file_flush(BlkLogWritesFileReq *fr)
+{
+ return bdrv_co_flush(fr->bs->file->bs);
+}
+
+static int coroutine_fn
+blk_log_writes_co_do_file_pdiscard(BlkLogWritesFileReq *fr)
+{
+ return bdrv_co_pdiscard(fr->bs->file->bs, fr->offset, fr->bytes);
+}
+
+static int coroutine_fn
+blk_log_writes_co_pwritev(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
+ QEMUIOVector *qiov, int flags)
+{
+ return blk_log_writes_co_log(bs, offset, bytes, qiov, flags,
+ blk_log_writes_co_do_file_pwritev, 0, false);
+}
+
+static int coroutine_fn
+blk_log_writes_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset, int bytes,
+ BdrvRequestFlags flags)
+{
+ return blk_log_writes_co_log(bs, offset, bytes, NULL, flags,
+ blk_log_writes_co_do_file_pwrite_zeroes, 0,
+ true);
+}
+
+static int coroutine_fn blk_log_writes_co_flush_to_disk(BlockDriverState *bs)
+{
+ return blk_log_writes_co_log(bs, 0, 0, NULL, 0,
+ blk_log_writes_co_do_file_flush,
+ LOG_FLUSH_FLAG, false);
+}
+
+static int coroutine_fn
+blk_log_writes_co_pdiscard(BlockDriverState *bs, int64_t offset, int count)
+{
+ return blk_log_writes_co_log(bs, offset, count, NULL, 0,
+ blk_log_writes_co_do_file_pdiscard,
+ LOG_DISCARD_FLAG, false);
+}
+
+static BlockDriver bdrv_blk_log_writes = {
+ .format_name = "blklogwrites",
+ .instance_size = sizeof(BDRVBlkLogWritesState),
+
+ .bdrv_open = blk_log_writes_open,
+ .bdrv_close = blk_log_writes_close,
+ .bdrv_getlength = blk_log_writes_getlength,
+ .bdrv_refresh_filename = blk_log_writes_refresh_filename,
+ .bdrv_child_perm = blk_log_writes_child_perm,
+ .bdrv_refresh_limits = blk_log_writes_refresh_limits,
+
+ .bdrv_co_preadv = blk_log_writes_co_preadv,
+ .bdrv_co_pwritev = blk_log_writes_co_pwritev,
+ .bdrv_co_pwrite_zeroes = blk_log_writes_co_pwrite_zeroes,
+ .bdrv_co_flush_to_disk = blk_log_writes_co_flush_to_disk,
+ .bdrv_co_pdiscard = blk_log_writes_co_pdiscard,
+ .bdrv_co_block_status = bdrv_co_block_status_from_file,
+
+ .is_filter = true,
+};
+
+static void bdrv_blk_log_writes_init(void)
+{
+ bdrv_register(&bdrv_blk_log_writes);
+}
+
+block_init(bdrv_blk_log_writes_init);
# @throttle: Since 2.11
# @nvme: Since 2.12
# @copy-on-read: Since 3.0
+# @blklogwrites: Since 3.0
#
# Since: 2.9
##
{ 'enum': 'BlockdevDriver',
- 'data': [ 'blkdebug', 'blkverify', 'bochs', 'cloop', 'copy-on-read',
- 'dmg', 'file', 'ftp', 'ftps', 'gluster', 'host_cdrom',
- 'host_device', 'http', 'https', 'iscsi', 'luks', 'nbd', 'nfs',
- 'null-aio', 'null-co', 'nvme', 'parallels', 'qcow', 'qcow2', 'qed',
- 'quorum', 'raw', 'rbd', 'replication', 'sheepdog', 'ssh',
- 'throttle', 'vdi', 'vhdx', 'vmdk', 'vpc', 'vvfat', 'vxhs' ] }
+ 'data': [ 'blkdebug', 'blklogwrites', 'blkverify', 'bochs', 'cloop',
+ 'copy-on-read', 'dmg', 'file', 'ftp', 'ftps', 'gluster',
+ 'host_cdrom', 'host_device', 'http', 'https', 'iscsi', 'luks',
+ 'nbd', 'nfs', 'null-aio', 'null-co', 'nvme', 'parallels', 'qcow',
+ 'qcow2', 'qed', 'quorum', 'raw', 'rbd', 'replication', 'sheepdog',
+ 'ssh', 'throttle', 'vdi', 'vhdx', 'vmdk', 'vpc', 'vvfat', 'vxhs' ] }
##
# @BlockdevOptionsFile:
'*inject-error': ['BlkdebugInjectErrorOptions'],
'*set-state': ['BlkdebugSetStateOptions'] } }
+##
+# @BlockdevOptionsBlklogwrites:
+#
+# Driver specific block device options for blklogwrites.
+#
+# @file: block device
+#
+# @log: block device used to log writes to @file
+#
+# @log-sector-size: sector size used in logging writes to @file, determines
+# granularity of offsets and sizes of writes (default: 512)
+#
+# Since: 3.0
+##
+{ 'struct': 'BlockdevOptionsBlklogwrites',
+ 'data': { 'file': 'BlockdevRef',
+ 'log': 'BlockdevRef',
+ '*log-sector-size': 'uint32' } }
+
##
# @BlockdevOptionsBlkverify:
#
'discriminator': 'driver',
'data': {
'blkdebug': 'BlockdevOptionsBlkdebug',
+ 'blklogwrites':'BlockdevOptionsBlklogwrites',
'blkverify': 'BlockdevOptionsBlkverify',
'bochs': 'BlockdevOptionsGenericFormat',
'cloop': 'BlockdevOptionsGenericFormat',
projects / qemu.git / commitdiff