Import QEMU upstream snapshot d2e570c

Upstream: https://gitlab.com/qemu-project/qemu.git

Upstream-Commit: d2e570cc0f97b936902a5b1b86b73c0f5998b475

block/blkverify.c

@@ -0,0 +1,344 @@
+/*
+ * Block protocol for block driver correctness testing
+ *
+ * Copyright (C) 2010 IBM, Corp.
+ *
+ * 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-io.h"
+#include "block/block_int.h"
+#include "qobject/qdict.h"
+#include "qobject/qstring.h"
+#include "qemu/cutils.h"
+#include "qemu/module.h"
+#include "qemu/option.h"
+#include "qemu/memalign.h"
+
+typedef struct {
+    BdrvChild *test_file;
+} BDRVBlkverifyState;
+
+typedef struct BlkverifyRequest {
+    Coroutine *co;
+    BlockDriverState *bs;
+
+    /* Request metadata */
+    bool is_write;
+    uint64_t offset;
+    uint64_t bytes;
+    int flags;
+
+    int GRAPH_RDLOCK_PTR (*request_fn)(
+        BdrvChild *, int64_t, int64_t, QEMUIOVector *, BdrvRequestFlags);
+
+    int ret;                    /* test image result */
+    int raw_ret;                /* raw image result */
+
+    unsigned int done;          /* completion counter */
+
+    QEMUIOVector *qiov;         /* user I/O vector */
+    QEMUIOVector *raw_qiov;     /* cloned I/O vector for raw file */
+} BlkverifyRequest;
+
+static void G_GNUC_PRINTF(2, 3) blkverify_err(BlkverifyRequest *r,
+                                             const char *fmt, ...)
+{
+    va_list ap;
+
+    va_start(ap, fmt);
+    fprintf(stderr, "blkverify: %s offset=%" PRId64 " bytes=%" PRId64 " ",
+            r->is_write ? "write" : "read", r->offset, r->bytes);
+    vfprintf(stderr, fmt, ap);
+    fprintf(stderr, "\n");
+    va_end(ap);
+    exit(1);
+}
+
+/* Valid blkverify filenames look like blkverify:path/to/raw_image:path/to/image */
+static void blkverify_parse_filename(const char *filename, QDict *options,
+                                     Error **errp)
+{
+    const char *c;
+    QString *raw_path;
+
+
+    /* Parse the blkverify: prefix */
+    if (!strstart(filename, "blkverify:", &filename)) {
+        /* There was no prefix; therefore, all options have to be already
+           present in the QDict (except for the filename) */
+        qdict_put_str(options, "x-image", filename);
+        return;
+    }
+
+    /* Parse the raw image filename */
+    c = strchr(filename, ':');
+    if (c == NULL) {
+        error_setg(errp, "blkverify requires raw copy and original image path");
+        return;
+    }
+
+    /* TODO Implement option pass-through and set raw.filename here */
+    raw_path = qstring_from_substr(filename, 0, c - filename);
+    qdict_put(options, "x-raw", raw_path);
+
+    /* TODO Allow multi-level nesting and set file.filename here */
+    filename = c + 1;
+    qdict_put_str(options, "x-image", filename);
+}
+
+static QemuOptsList runtime_opts = {
+    .name = "blkverify",
+    .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
+    .desc = {
+        {
+            .name = "x-raw",
+            .type = QEMU_OPT_STRING,
+            .help = "[internal use only, will be removed]",
+        },
+        {
+            .name = "x-image",
+            .type = QEMU_OPT_STRING,
+            .help = "[internal use only, will be removed]",
+        },
+        { /* end of list */ }
+    },
+};
+
+static int blkverify_open(BlockDriverState *bs, QDict *options, int flags,
+                          Error **errp)
+{
+    BDRVBlkverifyState *s = bs->opaque;
+    QemuOpts *opts;
+    int ret;
+
+    opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
+    if (!qemu_opts_absorb_qdict(opts, options, errp)) {
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    /* Open the raw file */
+    ret = bdrv_open_file_child(qemu_opt_get(opts, "x-raw"), options, "raw",
+                               bs, errp);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    /* Open the test file */
+    s->test_file = bdrv_open_child(qemu_opt_get(opts, "x-image"), options,
+                                   "test", bs, &child_of_bds, BDRV_CHILD_DATA,
+                                   false, errp);
+    if (!s->test_file) {
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED;
+    bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED;
+
+    ret = 0;
+fail:
+    qemu_opts_del(opts);
+    return ret;
+}
+
+static void blkverify_close(BlockDriverState *bs)
+{
+    BDRVBlkverifyState *s = bs->opaque;
+
+    bdrv_graph_wrlock_drained();
+    bdrv_unref_child(bs, s->test_file);
+    s->test_file = NULL;
+    bdrv_graph_wrunlock();
+}
+
+static int64_t coroutine_fn GRAPH_RDLOCK
+blkverify_co_getlength(BlockDriverState *bs)
+{
+    BDRVBlkverifyState *s = bs->opaque;
+
+    return bdrv_co_getlength(s->test_file->bs);
+}
+
+static void coroutine_fn blkverify_do_test_req(void *opaque)
+{
+    BlkverifyRequest *r = opaque;
+    BDRVBlkverifyState *s = r->bs->opaque;
+
+    bdrv_graph_co_rdlock();
+    r->ret = r->request_fn(s->test_file, r->offset, r->bytes, r->qiov,
+                           r->flags);
+    bdrv_graph_co_rdunlock();
+
+    r->done++;
+    qemu_coroutine_enter_if_inactive(r->co);
+}
+
+static void coroutine_fn blkverify_do_raw_req(void *opaque)
+{
+    BlkverifyRequest *r = opaque;
+
+    bdrv_graph_co_rdlock();
+    r->raw_ret = r->request_fn(r->bs->file, r->offset, r->bytes, r->raw_qiov,
+                               r->flags);
+    bdrv_graph_co_rdunlock();
+
+    r->done++;
+    qemu_coroutine_enter_if_inactive(r->co);
+}
+
+static int coroutine_fn GRAPH_RDLOCK
+blkverify_co_prwv(BlockDriverState *bs, BlkverifyRequest *r, uint64_t offset,
+                  uint64_t bytes, QEMUIOVector *qiov, QEMUIOVector *raw_qiov,
+                  int flags, bool is_write)
+{
+    Coroutine *co_a, *co_b;
+
+    *r = (BlkverifyRequest) {
+        .co         = qemu_coroutine_self(),
+        .bs         = bs,
+        .offset     = offset,
+        .bytes      = bytes,
+        .qiov       = qiov,
+        .raw_qiov   = raw_qiov,
+        .flags      = flags,
+        .is_write   = is_write,
+        .request_fn = is_write ? bdrv_co_pwritev : bdrv_co_preadv,
+    };
+
+    co_a = qemu_coroutine_create(blkverify_do_test_req, r);
+    co_b = qemu_coroutine_create(blkverify_do_raw_req, r);
+
+    qemu_coroutine_enter(co_a);
+    qemu_coroutine_enter(co_b);
+
+    while (r->done < 2) {
+        qemu_coroutine_yield();
+    }
+
+    if (r->ret != r->raw_ret) {
+        blkverify_err(r, "return value mismatch %d != %d", r->ret, r->raw_ret);
+    }
+
+    return r->ret;
+}
+
+static int coroutine_fn GRAPH_RDLOCK
+blkverify_co_preadv(BlockDriverState *bs, int64_t offset, int64_t bytes,
+                    QEMUIOVector *qiov, BdrvRequestFlags flags)
+{
+    BlkverifyRequest r;
+    QEMUIOVector raw_qiov;
+    void *buf;
+    ssize_t cmp_offset;
+    int ret;
+
+    buf = qemu_blockalign(bs->file->bs, qiov->size);
+    qemu_iovec_init(&raw_qiov, qiov->niov);
+    qemu_iovec_clone(&raw_qiov, qiov, buf);
+
+    ret = blkverify_co_prwv(bs, &r, offset, bytes, qiov, &raw_qiov,
+                            flags & ~BDRV_REQ_REGISTERED_BUF, false);
+
+    cmp_offset = qemu_iovec_compare(qiov, &raw_qiov);
+    if (cmp_offset != -1) {
+        blkverify_err(&r, "contents mismatch at offset %" PRId64,
+                      offset + cmp_offset);
+    }
+
+    qemu_iovec_destroy(&raw_qiov);
+    qemu_vfree(buf);
+
+    return ret;
+}
+
+static int coroutine_fn GRAPH_RDLOCK
+blkverify_co_pwritev(BlockDriverState *bs, int64_t offset, int64_t bytes,
+                     QEMUIOVector *qiov, BdrvRequestFlags flags)
+{
+    BlkverifyRequest r;
+    return blkverify_co_prwv(bs, &r, offset, bytes, qiov, qiov, flags, true);
+}
+
+static int coroutine_fn GRAPH_RDLOCK blkverify_co_flush(BlockDriverState *bs)
+{
+    BDRVBlkverifyState *s = bs->opaque;
+
+    /* Only flush test file, the raw file is not important */
+    return bdrv_co_flush(s->test_file->bs);
+}
+
+static bool GRAPH_RDLOCK
+blkverify_recurse_can_replace(BlockDriverState *bs,
+                              BlockDriverState *to_replace)
+{
+    BDRVBlkverifyState *s = bs->opaque;
+
+    /*
+     * blkverify quits the whole qemu process if there is a mismatch
+     * between bs->file->bs and s->test_file->bs.  Therefore, we know
+     * know that both must match bs and we can recurse down to either.
+     */
+    return bdrv_recurse_can_replace(bs->file->bs, to_replace) ||
+           bdrv_recurse_can_replace(s->test_file->bs, to_replace);
+}
+
+static void GRAPH_RDLOCK blkverify_refresh_filename(BlockDriverState *bs)
+{
+    BDRVBlkverifyState *s = bs->opaque;
+
+    if (bs->file->bs->exact_filename[0]
+        && s->test_file->bs->exact_filename[0])
+    {
+        int ret = snprintf(bs->exact_filename, sizeof(bs->exact_filename),
+                           "blkverify:%s:%s",
+                           bs->file->bs->exact_filename,
+                           s->test_file->bs->exact_filename);
+        if (ret >= sizeof(bs->exact_filename)) {
+            /* An overflow makes the filename unusable, so do not report any */
+            bs->exact_filename[0] = 0;
+        }
+    }
+}
+
+static char *blkverify_dirname(BlockDriverState *bs, Error **errp)
+{
+    /* In general, there are two BDSs with different dirnames below this one;
+     * so there is no unique dirname we could return (unless both are equal by
+     * chance). Therefore, to be consistent, just always return NULL. */
+    error_setg(errp, "Cannot generate a base directory for blkverify nodes");
+    return NULL;
+}
+
+static BlockDriver bdrv_blkverify = {
+    .format_name                      = "blkverify",
+    .protocol_name                    = "blkverify",
+    .instance_size                    = sizeof(BDRVBlkverifyState),
+
+    .bdrv_parse_filename              = blkverify_parse_filename,
+    .bdrv_open                        = blkverify_open,
+    .bdrv_close                       = blkverify_close,
+    .bdrv_child_perm                  = bdrv_default_perms,
+    .bdrv_co_getlength                = blkverify_co_getlength,
+    .bdrv_refresh_filename            = blkverify_refresh_filename,
+    .bdrv_dirname                     = blkverify_dirname,
+
+    .bdrv_co_preadv                   = blkverify_co_preadv,
+    .bdrv_co_pwritev                  = blkverify_co_pwritev,
+    .bdrv_co_flush                    = blkverify_co_flush,
+
+    .is_filter                        = true,
+    .bdrv_recurse_can_replace         = blkverify_recurse_can_replace,
+};
+
+static void bdrv_blkverify_init(void)
+{
+    bdrv_register(&bdrv_blkverify);
+}
+
+block_init(bdrv_blkverify_init);