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authorRajithaY <rajithax.yerrumsetty@intel.com>2017-04-25 03:31:15 -0700
committerRajitha Yerrumchetty <rajithax.yerrumsetty@intel.com>2017-05-22 06:48:08 +0000
commitbb756eebdac6fd24e8919e2c43f7d2c8c4091f59 (patch)
treeca11e03542edf2d8f631efeca5e1626d211107e3 /qemu/block/backup.c
parenta14b48d18a9ed03ec191cf16b162206998a895ce (diff)
Adding qemu as a submodule of KVMFORNFV
This Patch includes the changes to add qemu as a submodule to kvmfornfv repo and make use of the updated latest qemu for the execution of all testcase Change-Id: I1280af507a857675c7f81d30c95255635667bdd7 Signed-off-by:RajithaY<rajithax.yerrumsetty@intel.com>
Diffstat (limited to 'qemu/block/backup.c')
-rw-r--r--qemu/block/backup.c613
1 files changed, 0 insertions, 613 deletions
diff --git a/qemu/block/backup.c b/qemu/block/backup.c
deleted file mode 100644
index 491fd1406..000000000
--- a/qemu/block/backup.c
+++ /dev/null
@@ -1,613 +0,0 @@
-/*
- * QEMU backup
- *
- * Copyright (C) 2013 Proxmox Server Solutions
- *
- * Authors:
- * Dietmar Maurer (dietmar@proxmox.com)
- *
- * 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 "trace.h"
-#include "block/block.h"
-#include "block/block_int.h"
-#include "block/blockjob.h"
-#include "qapi/error.h"
-#include "qapi/qmp/qerror.h"
-#include "qemu/ratelimit.h"
-#include "qemu/cutils.h"
-#include "sysemu/block-backend.h"
-#include "qemu/bitmap.h"
-
-#define BACKUP_CLUSTER_SIZE_DEFAULT (1 << 16)
-#define SLICE_TIME 100000000ULL /* ns */
-
-typedef struct CowRequest {
- int64_t start;
- int64_t end;
- QLIST_ENTRY(CowRequest) list;
- CoQueue wait_queue; /* coroutines blocked on this request */
-} CowRequest;
-
-typedef struct BackupBlockJob {
- BlockJob common;
- BlockDriverState *target;
- /* bitmap for sync=incremental */
- BdrvDirtyBitmap *sync_bitmap;
- MirrorSyncMode sync_mode;
- RateLimit limit;
- BlockdevOnError on_source_error;
- BlockdevOnError on_target_error;
- CoRwlock flush_rwlock;
- uint64_t sectors_read;
- unsigned long *done_bitmap;
- int64_t cluster_size;
- QLIST_HEAD(, CowRequest) inflight_reqs;
-} BackupBlockJob;
-
-/* Size of a cluster in sectors, instead of bytes. */
-static inline int64_t cluster_size_sectors(BackupBlockJob *job)
-{
- return job->cluster_size / BDRV_SECTOR_SIZE;
-}
-
-/* See if in-flight requests overlap and wait for them to complete */
-static void coroutine_fn wait_for_overlapping_requests(BackupBlockJob *job,
- int64_t start,
- int64_t end)
-{
- CowRequest *req;
- bool retry;
-
- do {
- retry = false;
- QLIST_FOREACH(req, &job->inflight_reqs, list) {
- if (end > req->start && start < req->end) {
- qemu_co_queue_wait(&req->wait_queue);
- retry = true;
- break;
- }
- }
- } while (retry);
-}
-
-/* Keep track of an in-flight request */
-static void cow_request_begin(CowRequest *req, BackupBlockJob *job,
- int64_t start, int64_t end)
-{
- req->start = start;
- req->end = end;
- qemu_co_queue_init(&req->wait_queue);
- QLIST_INSERT_HEAD(&job->inflight_reqs, req, list);
-}
-
-/* Forget about a completed request */
-static void cow_request_end(CowRequest *req)
-{
- QLIST_REMOVE(req, list);
- qemu_co_queue_restart_all(&req->wait_queue);
-}
-
-static int coroutine_fn backup_do_cow(BlockDriverState *bs,
- int64_t sector_num, int nb_sectors,
- bool *error_is_read,
- bool is_write_notifier)
-{
- BackupBlockJob *job = (BackupBlockJob *)bs->job;
- CowRequest cow_request;
- struct iovec iov;
- QEMUIOVector bounce_qiov;
- void *bounce_buffer = NULL;
- int ret = 0;
- int64_t sectors_per_cluster = cluster_size_sectors(job);
- int64_t start, end;
- int n;
-
- qemu_co_rwlock_rdlock(&job->flush_rwlock);
-
- start = sector_num / sectors_per_cluster;
- end = DIV_ROUND_UP(sector_num + nb_sectors, sectors_per_cluster);
-
- trace_backup_do_cow_enter(job, start, sector_num, nb_sectors);
-
- wait_for_overlapping_requests(job, start, end);
- cow_request_begin(&cow_request, job, start, end);
-
- for (; start < end; start++) {
- if (test_bit(start, job->done_bitmap)) {
- trace_backup_do_cow_skip(job, start);
- continue; /* already copied */
- }
-
- trace_backup_do_cow_process(job, start);
-
- n = MIN(sectors_per_cluster,
- job->common.len / BDRV_SECTOR_SIZE -
- start * sectors_per_cluster);
-
- if (!bounce_buffer) {
- bounce_buffer = qemu_blockalign(bs, job->cluster_size);
- }
- iov.iov_base = bounce_buffer;
- iov.iov_len = n * BDRV_SECTOR_SIZE;
- qemu_iovec_init_external(&bounce_qiov, &iov, 1);
-
- if (is_write_notifier) {
- ret = bdrv_co_readv_no_serialising(bs,
- start * sectors_per_cluster,
- n, &bounce_qiov);
- } else {
- ret = bdrv_co_readv(bs, start * sectors_per_cluster, n,
- &bounce_qiov);
- }
- if (ret < 0) {
- trace_backup_do_cow_read_fail(job, start, ret);
- if (error_is_read) {
- *error_is_read = true;
- }
- goto out;
- }
-
- if (buffer_is_zero(iov.iov_base, iov.iov_len)) {
- ret = bdrv_co_write_zeroes(job->target,
- start * sectors_per_cluster,
- n, BDRV_REQ_MAY_UNMAP);
- } else {
- ret = bdrv_co_writev(job->target,
- start * sectors_per_cluster, n,
- &bounce_qiov);
- }
- if (ret < 0) {
- trace_backup_do_cow_write_fail(job, start, ret);
- if (error_is_read) {
- *error_is_read = false;
- }
- goto out;
- }
-
- set_bit(start, job->done_bitmap);
-
- /* Publish progress, guest I/O counts as progress too. Note that the
- * offset field is an opaque progress value, it is not a disk offset.
- */
- job->sectors_read += n;
- job->common.offset += n * BDRV_SECTOR_SIZE;
- }
-
-out:
- if (bounce_buffer) {
- qemu_vfree(bounce_buffer);
- }
-
- cow_request_end(&cow_request);
-
- trace_backup_do_cow_return(job, sector_num, nb_sectors, ret);
-
- qemu_co_rwlock_unlock(&job->flush_rwlock);
-
- return ret;
-}
-
-static int coroutine_fn backup_before_write_notify(
- NotifierWithReturn *notifier,
- void *opaque)
-{
- BdrvTrackedRequest *req = opaque;
- int64_t sector_num = req->offset >> BDRV_SECTOR_BITS;
- int nb_sectors = req->bytes >> BDRV_SECTOR_BITS;
-
- assert((req->offset & (BDRV_SECTOR_SIZE - 1)) == 0);
- assert((req->bytes & (BDRV_SECTOR_SIZE - 1)) == 0);
-
- return backup_do_cow(req->bs, sector_num, nb_sectors, NULL, true);
-}
-
-static void backup_set_speed(BlockJob *job, int64_t speed, Error **errp)
-{
- BackupBlockJob *s = container_of(job, BackupBlockJob, common);
-
- if (speed < 0) {
- error_setg(errp, QERR_INVALID_PARAMETER, "speed");
- return;
- }
- ratelimit_set_speed(&s->limit, speed / BDRV_SECTOR_SIZE, SLICE_TIME);
-}
-
-static void backup_iostatus_reset(BlockJob *job)
-{
- BackupBlockJob *s = container_of(job, BackupBlockJob, common);
-
- if (s->target->blk) {
- blk_iostatus_reset(s->target->blk);
- }
-}
-
-static void backup_cleanup_sync_bitmap(BackupBlockJob *job, int ret)
-{
- BdrvDirtyBitmap *bm;
- BlockDriverState *bs = job->common.bs;
-
- if (ret < 0 || block_job_is_cancelled(&job->common)) {
- /* Merge the successor back into the parent, delete nothing. */
- bm = bdrv_reclaim_dirty_bitmap(bs, job->sync_bitmap, NULL);
- assert(bm);
- } else {
- /* Everything is fine, delete this bitmap and install the backup. */
- bm = bdrv_dirty_bitmap_abdicate(bs, job->sync_bitmap, NULL);
- assert(bm);
- }
-}
-
-static void backup_commit(BlockJob *job)
-{
- BackupBlockJob *s = container_of(job, BackupBlockJob, common);
- if (s->sync_bitmap) {
- backup_cleanup_sync_bitmap(s, 0);
- }
-}
-
-static void backup_abort(BlockJob *job)
-{
- BackupBlockJob *s = container_of(job, BackupBlockJob, common);
- if (s->sync_bitmap) {
- backup_cleanup_sync_bitmap(s, -1);
- }
-}
-
-static const BlockJobDriver backup_job_driver = {
- .instance_size = sizeof(BackupBlockJob),
- .job_type = BLOCK_JOB_TYPE_BACKUP,
- .set_speed = backup_set_speed,
- .iostatus_reset = backup_iostatus_reset,
- .commit = backup_commit,
- .abort = backup_abort,
-};
-
-static BlockErrorAction backup_error_action(BackupBlockJob *job,
- bool read, int error)
-{
- if (read) {
- return block_job_error_action(&job->common, job->common.bs,
- job->on_source_error, true, error);
- } else {
- return block_job_error_action(&job->common, job->target,
- job->on_target_error, false, error);
- }
-}
-
-typedef struct {
- int ret;
-} BackupCompleteData;
-
-static void backup_complete(BlockJob *job, void *opaque)
-{
- BackupBlockJob *s = container_of(job, BackupBlockJob, common);
- BackupCompleteData *data = opaque;
-
- bdrv_unref(s->target);
-
- block_job_completed(job, data->ret);
- g_free(data);
-}
-
-static bool coroutine_fn yield_and_check(BackupBlockJob *job)
-{
- if (block_job_is_cancelled(&job->common)) {
- return true;
- }
-
- /* we need to yield so that bdrv_drain_all() returns.
- * (without, VM does not reboot)
- */
- if (job->common.speed) {
- uint64_t delay_ns = ratelimit_calculate_delay(&job->limit,
- job->sectors_read);
- job->sectors_read = 0;
- block_job_sleep_ns(&job->common, QEMU_CLOCK_REALTIME, delay_ns);
- } else {
- block_job_sleep_ns(&job->common, QEMU_CLOCK_REALTIME, 0);
- }
-
- if (block_job_is_cancelled(&job->common)) {
- return true;
- }
-
- return false;
-}
-
-static int coroutine_fn backup_run_incremental(BackupBlockJob *job)
-{
- bool error_is_read;
- int ret = 0;
- int clusters_per_iter;
- uint32_t granularity;
- int64_t sector;
- int64_t cluster;
- int64_t end;
- int64_t last_cluster = -1;
- int64_t sectors_per_cluster = cluster_size_sectors(job);
- BlockDriverState *bs = job->common.bs;
- HBitmapIter hbi;
-
- granularity = bdrv_dirty_bitmap_granularity(job->sync_bitmap);
- clusters_per_iter = MAX((granularity / job->cluster_size), 1);
- bdrv_dirty_iter_init(job->sync_bitmap, &hbi);
-
- /* Find the next dirty sector(s) */
- while ((sector = hbitmap_iter_next(&hbi)) != -1) {
- cluster = sector / sectors_per_cluster;
-
- /* Fake progress updates for any clusters we skipped */
- if (cluster != last_cluster + 1) {
- job->common.offset += ((cluster - last_cluster - 1) *
- job->cluster_size);
- }
-
- for (end = cluster + clusters_per_iter; cluster < end; cluster++) {
- do {
- if (yield_and_check(job)) {
- return ret;
- }
- ret = backup_do_cow(bs, cluster * sectors_per_cluster,
- sectors_per_cluster, &error_is_read,
- false);
- if ((ret < 0) &&
- backup_error_action(job, error_is_read, -ret) ==
- BLOCK_ERROR_ACTION_REPORT) {
- return ret;
- }
- } while (ret < 0);
- }
-
- /* If the bitmap granularity is smaller than the backup granularity,
- * we need to advance the iterator pointer to the next cluster. */
- if (granularity < job->cluster_size) {
- bdrv_set_dirty_iter(&hbi, cluster * sectors_per_cluster);
- }
-
- last_cluster = cluster - 1;
- }
-
- /* Play some final catchup with the progress meter */
- end = DIV_ROUND_UP(job->common.len, job->cluster_size);
- if (last_cluster + 1 < end) {
- job->common.offset += ((end - last_cluster - 1) * job->cluster_size);
- }
-
- return ret;
-}
-
-static void coroutine_fn backup_run(void *opaque)
-{
- BackupBlockJob *job = opaque;
- BackupCompleteData *data;
- BlockDriverState *bs = job->common.bs;
- BlockDriverState *target = job->target;
- BlockdevOnError on_target_error = job->on_target_error;
- NotifierWithReturn before_write = {
- .notify = backup_before_write_notify,
- };
- int64_t start, end;
- int64_t sectors_per_cluster = cluster_size_sectors(job);
- int ret = 0;
-
- QLIST_INIT(&job->inflight_reqs);
- qemu_co_rwlock_init(&job->flush_rwlock);
-
- start = 0;
- end = DIV_ROUND_UP(job->common.len, job->cluster_size);
-
- job->done_bitmap = bitmap_new(end);
-
- if (target->blk) {
- blk_set_on_error(target->blk, on_target_error, on_target_error);
- blk_iostatus_enable(target->blk);
- }
-
- bdrv_add_before_write_notifier(bs, &before_write);
-
- if (job->sync_mode == MIRROR_SYNC_MODE_NONE) {
- while (!block_job_is_cancelled(&job->common)) {
- /* Yield until the job is cancelled. We just let our before_write
- * notify callback service CoW requests. */
- job->common.busy = false;
- qemu_coroutine_yield();
- job->common.busy = true;
- }
- } else if (job->sync_mode == MIRROR_SYNC_MODE_INCREMENTAL) {
- ret = backup_run_incremental(job);
- } else {
- /* Both FULL and TOP SYNC_MODE's require copying.. */
- for (; start < end; start++) {
- bool error_is_read;
- if (yield_and_check(job)) {
- break;
- }
-
- if (job->sync_mode == MIRROR_SYNC_MODE_TOP) {
- int i, n;
- int alloced = 0;
-
- /* Check to see if these blocks are already in the
- * backing file. */
-
- for (i = 0; i < sectors_per_cluster;) {
- /* bdrv_is_allocated() only returns true/false based
- * on the first set of sectors it comes across that
- * are are all in the same state.
- * For that reason we must verify each sector in the
- * backup cluster length. We end up copying more than
- * needed but at some point that is always the case. */
- alloced =
- bdrv_is_allocated(bs,
- start * sectors_per_cluster + i,
- sectors_per_cluster - i, &n);
- i += n;
-
- if (alloced == 1 || n == 0) {
- break;
- }
- }
-
- /* If the above loop never found any sectors that are in
- * the topmost image, skip this backup. */
- if (alloced == 0) {
- continue;
- }
- }
- /* FULL sync mode we copy the whole drive. */
- ret = backup_do_cow(bs, start * sectors_per_cluster,
- sectors_per_cluster, &error_is_read, false);
- if (ret < 0) {
- /* Depending on error action, fail now or retry cluster */
- BlockErrorAction action =
- backup_error_action(job, error_is_read, -ret);
- if (action == BLOCK_ERROR_ACTION_REPORT) {
- break;
- } else {
- start--;
- continue;
- }
- }
- }
- }
-
- notifier_with_return_remove(&before_write);
-
- /* wait until pending backup_do_cow() calls have completed */
- qemu_co_rwlock_wrlock(&job->flush_rwlock);
- qemu_co_rwlock_unlock(&job->flush_rwlock);
- g_free(job->done_bitmap);
-
- if (target->blk) {
- blk_iostatus_disable(target->blk);
- }
- bdrv_op_unblock_all(target, job->common.blocker);
-
- data = g_malloc(sizeof(*data));
- data->ret = ret;
- block_job_defer_to_main_loop(&job->common, backup_complete, data);
-}
-
-void backup_start(BlockDriverState *bs, BlockDriverState *target,
- int64_t speed, MirrorSyncMode sync_mode,
- BdrvDirtyBitmap *sync_bitmap,
- BlockdevOnError on_source_error,
- BlockdevOnError on_target_error,
- BlockCompletionFunc *cb, void *opaque,
- BlockJobTxn *txn, Error **errp)
-{
- int64_t len;
- BlockDriverInfo bdi;
- int ret;
-
- assert(bs);
- assert(target);
- assert(cb);
-
- if (bs == target) {
- error_setg(errp, "Source and target cannot be the same");
- return;
- }
-
- if ((on_source_error == BLOCKDEV_ON_ERROR_STOP ||
- on_source_error == BLOCKDEV_ON_ERROR_ENOSPC) &&
- (!bs->blk || !blk_iostatus_is_enabled(bs->blk))) {
- error_setg(errp, QERR_INVALID_PARAMETER, "on-source-error");
- return;
- }
-
- if (!bdrv_is_inserted(bs)) {
- error_setg(errp, "Device is not inserted: %s",
- bdrv_get_device_name(bs));
- return;
- }
-
- if (!bdrv_is_inserted(target)) {
- error_setg(errp, "Device is not inserted: %s",
- bdrv_get_device_name(target));
- return;
- }
-
- if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
- return;
- }
-
- if (bdrv_op_is_blocked(target, BLOCK_OP_TYPE_BACKUP_TARGET, errp)) {
- return;
- }
-
- if (sync_mode == MIRROR_SYNC_MODE_INCREMENTAL) {
- if (!sync_bitmap) {
- error_setg(errp, "must provide a valid bitmap name for "
- "\"incremental\" sync mode");
- return;
- }
-
- /* Create a new bitmap, and freeze/disable this one. */
- if (bdrv_dirty_bitmap_create_successor(bs, sync_bitmap, errp) < 0) {
- return;
- }
- } else if (sync_bitmap) {
- error_setg(errp,
- "a sync_bitmap was provided to backup_run, "
- "but received an incompatible sync_mode (%s)",
- MirrorSyncMode_lookup[sync_mode]);
- return;
- }
-
- len = bdrv_getlength(bs);
- if (len < 0) {
- error_setg_errno(errp, -len, "unable to get length for '%s'",
- bdrv_get_device_name(bs));
- goto error;
- }
-
- BackupBlockJob *job = block_job_create(&backup_job_driver, bs, speed,
- cb, opaque, errp);
- if (!job) {
- goto error;
- }
-
- job->on_source_error = on_source_error;
- job->on_target_error = on_target_error;
- job->target = target;
- job->sync_mode = sync_mode;
- job->sync_bitmap = sync_mode == MIRROR_SYNC_MODE_INCREMENTAL ?
- sync_bitmap : NULL;
-
- /* If there is no backing file on the target, we cannot rely on COW if our
- * backup cluster size is smaller than the target cluster size. Even for
- * targets with a backing file, try to avoid COW if possible. */
- ret = bdrv_get_info(job->target, &bdi);
- if (ret < 0 && !target->backing) {
- error_setg_errno(errp, -ret,
- "Couldn't determine the cluster size of the target image, "
- "which has no backing file");
- error_append_hint(errp,
- "Aborting, since this may create an unusable destination image\n");
- goto error;
- } else if (ret < 0 && target->backing) {
- /* Not fatal; just trudge on ahead. */
- job->cluster_size = BACKUP_CLUSTER_SIZE_DEFAULT;
- } else {
- job->cluster_size = MAX(BACKUP_CLUSTER_SIZE_DEFAULT, bdi.cluster_size);
- }
-
- bdrv_op_block_all(target, job->common.blocker);
- job->common.len = len;
- job->common.co = qemu_coroutine_create(backup_run);
- block_job_txn_add_job(txn, &job->common);
- qemu_coroutine_enter(job->common.co, job);
- return;
-
- error:
- if (sync_bitmap) {
- bdrv_reclaim_dirty_bitmap(bs, sync_bitmap, NULL);
- }
-}