diff options
Diffstat (limited to 'block/blkdebug.c')
| -rw-r--r-- | block/blkdebug.c | 1108 |
1 files changed, 1108 insertions, 0 deletions
diff --git a/block/blkdebug.c b/block/blkdebug.c new file mode 100644 index 000000000..bbf294870 --- /dev/null +++ b/block/blkdebug.c @@ -0,0 +1,1108 @@ +/* + * Block protocol for I/O error injection + * + * Copyright (C) 2016-2017 Red Hat, Inc. + * Copyright (c) 2010 Kevin Wolf <kwolf@redhat.com> + * + * 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 "qemu/osdep.h" +#include "qapi/error.h" +#include "qemu/cutils.h" +#include "qemu/config-file.h" +#include "block/block_int.h" +#include "block/qdict.h" +#include "qemu/module.h" +#include "qemu/option.h" +#include "qapi/qapi-visit-block-core.h" +#include "qapi/qmp/qdict.h" +#include "qapi/qmp/qlist.h" +#include "qapi/qmp/qstring.h" +#include "qapi/qobject-input-visitor.h" +#include "sysemu/qtest.h" + +/* All APIs are thread-safe */ + +typedef struct BDRVBlkdebugState { + /* IN: initialized in blkdebug_open() and never changed */ + uint64_t align; + uint64_t max_transfer; + uint64_t opt_write_zero; + uint64_t max_write_zero; + uint64_t opt_discard; + uint64_t max_discard; + char *config_file; /* For blkdebug_refresh_filename() */ + /* initialized in blkdebug_parse_perms() */ + uint64_t take_child_perms; + uint64_t unshare_child_perms; + + /* State. Protected by lock */ + int state; + QLIST_HEAD(, BlkdebugRule) rules[BLKDBG__MAX]; + QSIMPLEQ_HEAD(, BlkdebugRule) active_rules; + QLIST_HEAD(, BlkdebugSuspendedReq) suspended_reqs; + QemuMutex lock; +} BDRVBlkdebugState; + +typedef struct BlkdebugAIOCB { + BlockAIOCB common; + int ret; +} BlkdebugAIOCB; + +typedef struct BlkdebugSuspendedReq { + /* IN: initialized in suspend_request() */ + Coroutine *co; + char *tag; + + /* List entry protected BDRVBlkdebugState's lock */ + QLIST_ENTRY(BlkdebugSuspendedReq) next; +} BlkdebugSuspendedReq; + +enum { + ACTION_INJECT_ERROR, + ACTION_SET_STATE, + ACTION_SUSPEND, + ACTION__MAX, +}; + +typedef struct BlkdebugRule { + /* IN: initialized in add_rule() or blkdebug_debug_breakpoint() */ + BlkdebugEvent event; + int action; + int state; + union { + struct { + uint64_t iotype_mask; + int error; + int immediately; + int once; + int64_t offset; + } inject; + struct { + int new_state; + } set_state; + struct { + char *tag; + } suspend; + } options; + + /* List entries protected BDRVBlkdebugState's lock */ + QLIST_ENTRY(BlkdebugRule) next; + QSIMPLEQ_ENTRY(BlkdebugRule) active_next; +} BlkdebugRule; + +QEMU_BUILD_BUG_MSG(BLKDEBUG_IO_TYPE__MAX > 64, + "BlkdebugIOType mask does not fit into an uint64_t"); + +static QemuOptsList inject_error_opts = { + .name = "inject-error", + .head = QTAILQ_HEAD_INITIALIZER(inject_error_opts.head), + .desc = { + { + .name = "event", + .type = QEMU_OPT_STRING, + }, + { + .name = "state", + .type = QEMU_OPT_NUMBER, + }, + { + .name = "iotype", + .type = QEMU_OPT_STRING, + }, + { + .name = "errno", + .type = QEMU_OPT_NUMBER, + }, + { + .name = "sector", + .type = QEMU_OPT_NUMBER, + }, + { + .name = "once", + .type = QEMU_OPT_BOOL, + }, + { + .name = "immediately", + .type = QEMU_OPT_BOOL, + }, + { /* end of list */ } + }, +}; + +static QemuOptsList set_state_opts = { + .name = "set-state", + .head = QTAILQ_HEAD_INITIALIZER(set_state_opts.head), + .desc = { + { + .name = "event", + .type = QEMU_OPT_STRING, + }, + { + .name = "state", + .type = QEMU_OPT_NUMBER, + }, + { + .name = "new_state", + .type = QEMU_OPT_NUMBER, + }, + { /* end of list */ } + }, +}; + +static QemuOptsList *config_groups[] = { + &inject_error_opts, + &set_state_opts, + NULL +}; + +struct add_rule_data { + BDRVBlkdebugState *s; + int action; +}; + +static int add_rule(void *opaque, QemuOpts *opts, Error **errp) +{ + struct add_rule_data *d = opaque; + BDRVBlkdebugState *s = d->s; + const char *event_name; + int event; + struct BlkdebugRule *rule; + int64_t sector; + BlkdebugIOType iotype; + Error *local_error = NULL; + + /* Find the right event for the rule */ + event_name = qemu_opt_get(opts, "event"); + if (!event_name) { + error_setg(errp, "Missing event name for rule"); + return -1; + } + event = qapi_enum_parse(&BlkdebugEvent_lookup, event_name, -1, errp); + if (event < 0) { + return -1; + } + + /* Set attributes common for all actions */ + rule = g_malloc0(sizeof(*rule)); + *rule = (struct BlkdebugRule) { + .event = event, + .action = d->action, + .state = qemu_opt_get_number(opts, "state", 0), + }; + + /* Parse action-specific options */ + switch (d->action) { + case ACTION_INJECT_ERROR: + rule->options.inject.error = qemu_opt_get_number(opts, "errno", EIO); + rule->options.inject.once = qemu_opt_get_bool(opts, "once", 0); + rule->options.inject.immediately = + qemu_opt_get_bool(opts, "immediately", 0); + sector = qemu_opt_get_number(opts, "sector", -1); + rule->options.inject.offset = + sector == -1 ? -1 : sector * BDRV_SECTOR_SIZE; + + iotype = qapi_enum_parse(&BlkdebugIOType_lookup, + qemu_opt_get(opts, "iotype"), + BLKDEBUG_IO_TYPE__MAX, &local_error); + if (local_error) { + error_propagate(errp, local_error); + g_free(rule); + return -1; + } + if (iotype != BLKDEBUG_IO_TYPE__MAX) { + rule->options.inject.iotype_mask = (1ull << iotype); + } else { + /* Apply the default */ + rule->options.inject.iotype_mask = + (1ull << BLKDEBUG_IO_TYPE_READ) + | (1ull << BLKDEBUG_IO_TYPE_WRITE) + | (1ull << BLKDEBUG_IO_TYPE_WRITE_ZEROES) + | (1ull << BLKDEBUG_IO_TYPE_DISCARD) + | (1ull << BLKDEBUG_IO_TYPE_FLUSH); + } + + break; + + case ACTION_SET_STATE: + rule->options.set_state.new_state = + qemu_opt_get_number(opts, "new_state", 0); + break; + + case ACTION_SUSPEND: + rule->options.suspend.tag = + g_strdup(qemu_opt_get(opts, "tag")); + break; + }; + + /* Add the rule */ + qemu_mutex_lock(&s->lock); + QLIST_INSERT_HEAD(&s->rules[event], rule, next); + qemu_mutex_unlock(&s->lock); + + return 0; +} + +/* Called with lock held or from .bdrv_close */ +static void remove_rule(BlkdebugRule *rule) +{ + switch (rule->action) { + case ACTION_INJECT_ERROR: + case ACTION_SET_STATE: + break; + case ACTION_SUSPEND: + g_free(rule->options.suspend.tag); + break; + } + + QLIST_REMOVE(rule, next); + g_free(rule); +} + +static int read_config(BDRVBlkdebugState *s, const char *filename, + QDict *options, Error **errp) +{ + FILE *f = NULL; + int ret; + struct add_rule_data d; + Error *local_err = NULL; + + if (filename) { + f = fopen(filename, "r"); + if (f == NULL) { + error_setg_errno(errp, errno, "Could not read blkdebug config file"); + return -errno; + } + + ret = qemu_config_parse(f, config_groups, filename, errp); + if (ret < 0) { + goto fail; + } + } + + qemu_config_parse_qdict(options, config_groups, &local_err); + if (local_err) { + error_propagate(errp, local_err); + ret = -EINVAL; + goto fail; + } + + d.s = s; + d.action = ACTION_INJECT_ERROR; + qemu_opts_foreach(&inject_error_opts, add_rule, &d, &local_err); + if (local_err) { + error_propagate(errp, local_err); + ret = -EINVAL; + goto fail; + } + + d.action = ACTION_SET_STATE; + qemu_opts_foreach(&set_state_opts, add_rule, &d, &local_err); + if (local_err) { + error_propagate(errp, local_err); + ret = -EINVAL; + goto fail; + } + + ret = 0; +fail: + qemu_opts_reset(&inject_error_opts); + qemu_opts_reset(&set_state_opts); + if (f) { + fclose(f); + } + return ret; +} + +/* Valid blkdebug filenames look like blkdebug:path/to/config:path/to/image */ +static void blkdebug_parse_filename(const char *filename, QDict *options, + Error **errp) +{ + const char *c; + + /* Parse the blkdebug: prefix */ + if (!strstart(filename, "blkdebug:", &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 config file path */ + c = strchr(filename, ':'); + if (c == NULL) { + error_setg(errp, "blkdebug requires both config file and image path"); + return; + } + + if (c != filename) { + QString *config_path; + config_path = qstring_from_substr(filename, 0, c - filename); + qdict_put(options, "config", config_path); + } + + /* TODO Allow multi-level nesting and set file.filename here */ + filename = c + 1; + qdict_put_str(options, "x-image", filename); +} + +static int blkdebug_parse_perm_list(uint64_t *dest, QDict *options, + const char *prefix, Error **errp) +{ + int ret = 0; + QDict *subqdict = NULL; + QObject *crumpled_subqdict = NULL; + Visitor *v = NULL; + BlockPermissionList *perm_list = NULL, *element; + + *dest = 0; + + qdict_extract_subqdict(options, &subqdict, prefix); + if (!qdict_size(subqdict)) { + goto out; + } + + crumpled_subqdict = qdict_crumple(subqdict, errp); + if (!crumpled_subqdict) { + ret = -EINVAL; + goto out; + } + + v = qobject_input_visitor_new(crumpled_subqdict); + if (!visit_type_BlockPermissionList(v, NULL, &perm_list, errp)) { + ret = -EINVAL; + goto out; + } + + for (element = perm_list; element; element = element->next) { + *dest |= bdrv_qapi_perm_to_blk_perm(element->value); + } + +out: + qapi_free_BlockPermissionList(perm_list); + visit_free(v); + qobject_unref(subqdict); + qobject_unref(crumpled_subqdict); + return ret; +} + +static int blkdebug_parse_perms(BDRVBlkdebugState *s, QDict *options, + Error **errp) +{ + int ret; + + ret = blkdebug_parse_perm_list(&s->take_child_perms, options, + "take-child-perms.", errp); + if (ret < 0) { + return ret; + } + + ret = blkdebug_parse_perm_list(&s->unshare_child_perms, options, + "unshare-child-perms.", errp); + if (ret < 0) { + return ret; + } + + return 0; +} + +static QemuOptsList runtime_opts = { + .name = "blkdebug", + .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), + .desc = { + { + .name = "config", + .type = QEMU_OPT_STRING, + .help = "Path to the configuration file", + }, + { + .name = "x-image", + .type = QEMU_OPT_STRING, + .help = "[internal use only, will be removed]", + }, + { + .name = "align", + .type = QEMU_OPT_SIZE, + .help = "Required alignment in bytes", + }, + { + .name = "max-transfer", + .type = QEMU_OPT_SIZE, + .help = "Maximum transfer size in bytes", + }, + { + .name = "opt-write-zero", + .type = QEMU_OPT_SIZE, + .help = "Optimum write zero alignment in bytes", + }, + { + .name = "max-write-zero", + .type = QEMU_OPT_SIZE, + .help = "Maximum write zero size in bytes", + }, + { + .name = "opt-discard", + .type = QEMU_OPT_SIZE, + .help = "Optimum discard alignment in bytes", + }, + { + .name = "max-discard", + .type = QEMU_OPT_SIZE, + .help = "Maximum discard size in bytes", + }, + { /* end of list */ } + }, +}; + +static int blkdebug_open(BlockDriverState *bs, QDict *options, int flags, + Error **errp) +{ + BDRVBlkdebugState *s = bs->opaque; + QemuOpts *opts; + int ret; + uint64_t align; + + qemu_mutex_init(&s->lock); + opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); + if (!qemu_opts_absorb_qdict(opts, options, errp)) { + ret = -EINVAL; + goto out; + } + + /* Read rules from config file or command line options */ + s->config_file = g_strdup(qemu_opt_get(opts, "config")); + ret = read_config(s, s->config_file, options, errp); + if (ret) { + goto out; + } + + /* Set initial state */ + s->state = 1; + + /* Parse permissions modifiers before opening the image file */ + ret = blkdebug_parse_perms(s, options, errp); + if (ret < 0) { + goto out; + } + + /* Open the image file */ + bs->file = bdrv_open_child(qemu_opt_get(opts, "x-image"), options, "image", + bs, &child_of_bds, + BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, + false, errp); + if (!bs->file) { + ret = -EINVAL; + goto out; + } + + bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED | + (BDRV_REQ_FUA & bs->file->bs->supported_write_flags); + bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED | + ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) & + bs->file->bs->supported_zero_flags); + ret = -EINVAL; + + /* Set alignment overrides */ + s->align = qemu_opt_get_size(opts, "align", 0); + if (s->align && (s->align >= INT_MAX || !is_power_of_2(s->align))) { + error_setg(errp, "Cannot meet constraints with align %" PRIu64, + s->align); + goto out; + } + align = MAX(s->align, bs->file->bs->bl.request_alignment); + + s->max_transfer = qemu_opt_get_size(opts, "max-transfer", 0); + if (s->max_transfer && + (s->max_transfer >= INT_MAX || + !QEMU_IS_ALIGNED(s->max_transfer, align))) { + error_setg(errp, "Cannot meet constraints with max-transfer %" PRIu64, + s->max_transfer); + goto out; + } + + s->opt_write_zero = qemu_opt_get_size(opts, "opt-write-zero", 0); + if (s->opt_write_zero && + (s->opt_write_zero >= INT_MAX || + !QEMU_IS_ALIGNED(s->opt_write_zero, align))) { + error_setg(errp, "Cannot meet constraints with opt-write-zero %" PRIu64, + s->opt_write_zero); + goto out; + } + + s->max_write_zero = qemu_opt_get_size(opts, "max-write-zero", 0); + if (s->max_write_zero && + (s->max_write_zero >= INT_MAX || + !QEMU_IS_ALIGNED(s->max_write_zero, + MAX(s->opt_write_zero, align)))) { + error_setg(errp, "Cannot meet constraints with max-write-zero %" PRIu64, + s->max_write_zero); + goto out; + } + + s->opt_discard = qemu_opt_get_size(opts, "opt-discard", 0); + if (s->opt_discard && + (s->opt_discard >= INT_MAX || + !QEMU_IS_ALIGNED(s->opt_discard, align))) { + error_setg(errp, "Cannot meet constraints with opt-discard %" PRIu64, + s->opt_discard); + goto out; + } + + s->max_discard = qemu_opt_get_size(opts, "max-discard", 0); + if (s->max_discard && + (s->max_discard >= INT_MAX || + !QEMU_IS_ALIGNED(s->max_discard, + MAX(s->opt_discard, align)))) { + error_setg(errp, "Cannot meet constraints with max-discard %" PRIu64, + s->max_discard); + goto out; + } + + bdrv_debug_event(bs, BLKDBG_NONE); + + ret = 0; +out: + if (ret < 0) { + qemu_mutex_destroy(&s->lock); + g_free(s->config_file); + } + qemu_opts_del(opts); + return ret; +} + +static int rule_check(BlockDriverState *bs, uint64_t offset, uint64_t bytes, + BlkdebugIOType iotype) +{ + BDRVBlkdebugState *s = bs->opaque; + BlkdebugRule *rule = NULL; + int error; + bool immediately; + + qemu_mutex_lock(&s->lock); + QSIMPLEQ_FOREACH(rule, &s->active_rules, active_next) { + uint64_t inject_offset = rule->options.inject.offset; + + if ((inject_offset == -1 || + (bytes && inject_offset >= offset && + inject_offset < offset + bytes)) && + (rule->options.inject.iotype_mask & (1ull << iotype))) + { + break; + } + } + + if (!rule || !rule->options.inject.error) { + qemu_mutex_unlock(&s->lock); + return 0; + } + + immediately = rule->options.inject.immediately; + error = rule->options.inject.error; + + if (rule->options.inject.once) { + QSIMPLEQ_REMOVE(&s->active_rules, rule, BlkdebugRule, active_next); + remove_rule(rule); + } + + qemu_mutex_unlock(&s->lock); + if (!immediately) { + aio_co_schedule(qemu_get_current_aio_context(), qemu_coroutine_self()); + qemu_coroutine_yield(); + } + + return -error; +} + +static int coroutine_fn +blkdebug_co_preadv(BlockDriverState *bs, int64_t offset, int64_t bytes, + QEMUIOVector *qiov, BdrvRequestFlags flags) +{ + int err; + + /* Sanity check block layer guarantees */ + assert(QEMU_IS_ALIGNED(offset, bs->bl.request_alignment)); + assert(QEMU_IS_ALIGNED(bytes, bs->bl.request_alignment)); + if (bs->bl.max_transfer) { + assert(bytes <= bs->bl.max_transfer); + } + + err = rule_check(bs, offset, bytes, BLKDEBUG_IO_TYPE_READ); + if (err) { + return err; + } + + return bdrv_co_preadv(bs->file, offset, bytes, qiov, flags); +} + +static int coroutine_fn +blkdebug_co_pwritev(BlockDriverState *bs, int64_t offset, int64_t bytes, + QEMUIOVector *qiov, BdrvRequestFlags flags) +{ + int err; + + /* Sanity check block layer guarantees */ + assert(QEMU_IS_ALIGNED(offset, bs->bl.request_alignment)); + assert(QEMU_IS_ALIGNED(bytes, bs->bl.request_alignment)); + if (bs->bl.max_transfer) { + assert(bytes <= bs->bl.max_transfer); + } + + err = rule_check(bs, offset, bytes, BLKDEBUG_IO_TYPE_WRITE); + if (err) { + return err; + } + + return bdrv_co_pwritev(bs->file, offset, bytes, qiov, flags); +} + +static int blkdebug_co_flush(BlockDriverState *bs) +{ + int err = rule_check(bs, 0, 0, BLKDEBUG_IO_TYPE_FLUSH); + + if (err) { + return err; + } + + return bdrv_co_flush(bs->file->bs); +} + +static int coroutine_fn blkdebug_co_pwrite_zeroes(BlockDriverState *bs, + int64_t offset, int64_t bytes, + BdrvRequestFlags flags) +{ + uint32_t align = MAX(bs->bl.request_alignment, + bs->bl.pwrite_zeroes_alignment); + int err; + + /* Only pass through requests that are larger than requested + * preferred alignment (so that we test the fallback to writes on + * unaligned portions), and check that the block layer never hands + * us anything unaligned that crosses an alignment boundary. */ + if (bytes < align) { + assert(QEMU_IS_ALIGNED(offset, align) || + QEMU_IS_ALIGNED(offset + bytes, align) || + DIV_ROUND_UP(offset, align) == + DIV_ROUND_UP(offset + bytes, align)); + return -ENOTSUP; + } + assert(QEMU_IS_ALIGNED(offset, align)); + assert(QEMU_IS_ALIGNED(bytes, align)); + if (bs->bl.max_pwrite_zeroes) { + assert(bytes <= bs->bl.max_pwrite_zeroes); + } + + err = rule_check(bs, offset, bytes, BLKDEBUG_IO_TYPE_WRITE_ZEROES); + if (err) { + return err; + } + + return bdrv_co_pwrite_zeroes(bs->file, offset, bytes, flags); +} + +static int coroutine_fn blkdebug_co_pdiscard(BlockDriverState *bs, + int64_t offset, int64_t bytes) +{ + uint32_t align = bs->bl.pdiscard_alignment; + int err; + + /* Only pass through requests that are larger than requested + * minimum alignment, and ensure that unaligned requests do not + * cross optimum discard boundaries. */ + if (bytes < bs->bl.request_alignment) { + assert(QEMU_IS_ALIGNED(offset, align) || + QEMU_IS_ALIGNED(offset + bytes, align) || + DIV_ROUND_UP(offset, align) == + DIV_ROUND_UP(offset + bytes, align)); + return -ENOTSUP; + } + assert(QEMU_IS_ALIGNED(offset, bs->bl.request_alignment)); + assert(QEMU_IS_ALIGNED(bytes, bs->bl.request_alignment)); + if (align && bytes >= align) { + assert(QEMU_IS_ALIGNED(offset, align)); + assert(QEMU_IS_ALIGNED(bytes, align)); + } + if (bs->bl.max_pdiscard) { + assert(bytes <= bs->bl.max_pdiscard); + } + + err = rule_check(bs, offset, bytes, BLKDEBUG_IO_TYPE_DISCARD); + if (err) { + return err; + } + + return bdrv_co_pdiscard(bs->file, offset, bytes); +} + +static int coroutine_fn blkdebug_co_block_status(BlockDriverState *bs, + bool want_zero, + int64_t offset, + int64_t bytes, + int64_t *pnum, + int64_t *map, + BlockDriverState **file) +{ + int err; + + assert(QEMU_IS_ALIGNED(offset | bytes, bs->bl.request_alignment)); + + err = rule_check(bs, offset, bytes, BLKDEBUG_IO_TYPE_BLOCK_STATUS); + if (err) { + return err; + } + + assert(bs->file && bs->file->bs); + *pnum = bytes; + *map = offset; + *file = bs->file->bs; + return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID; +} + +static void blkdebug_close(BlockDriverState *bs) +{ + BDRVBlkdebugState *s = bs->opaque; + BlkdebugRule *rule, *next; + int i; + + for (i = 0; i < BLKDBG__MAX; i++) { + QLIST_FOREACH_SAFE(rule, &s->rules[i], next, next) { + remove_rule(rule); + } + } + + g_free(s->config_file); + qemu_mutex_destroy(&s->lock); +} + +/* Called with lock held. */ +static void suspend_request(BlockDriverState *bs, BlkdebugRule *rule) +{ + BDRVBlkdebugState *s = bs->opaque; + BlkdebugSuspendedReq *r; + + r = g_new(BlkdebugSuspendedReq, 1); + + r->co = qemu_coroutine_self(); + r->tag = g_strdup(rule->options.suspend.tag); + + remove_rule(rule); + QLIST_INSERT_HEAD(&s->suspended_reqs, r, next); + + if (!qtest_enabled()) { + printf("blkdebug: Suspended request '%s'\n", r->tag); + } +} + +/* Called with lock held. */ +static void process_rule(BlockDriverState *bs, struct BlkdebugRule *rule, + int *action_count, int *new_state) +{ + BDRVBlkdebugState *s = bs->opaque; + + /* Only process rules for the current state */ + if (rule->state && rule->state != s->state) { + return; + } + + /* Take the action */ + action_count[rule->action]++; + switch (rule->action) { + case ACTION_INJECT_ERROR: + if (action_count[ACTION_INJECT_ERROR] == 1) { + QSIMPLEQ_INIT(&s->active_rules); + } + QSIMPLEQ_INSERT_HEAD(&s->active_rules, rule, active_next); + break; + + case ACTION_SET_STATE: + *new_state = rule->options.set_state.new_state; + break; + + case ACTION_SUSPEND: + suspend_request(bs, rule); + break; + } +} + +static void blkdebug_debug_event(BlockDriverState *bs, BlkdebugEvent event) +{ + BDRVBlkdebugState *s = bs->opaque; + struct BlkdebugRule *rule, *next; + int new_state; + int actions_count[ACTION__MAX] = { 0 }; + + assert((int)event >= 0 && event < BLKDBG__MAX); + + WITH_QEMU_LOCK_GUARD(&s->lock) { + new_state = s->state; + QLIST_FOREACH_SAFE(rule, &s->rules[event], next, next) { + process_rule(bs, rule, actions_count, &new_state); + } + s->state = new_state; + } + + while (actions_count[ACTION_SUSPEND] > 0) { + qemu_coroutine_yield(); + actions_count[ACTION_SUSPEND]--; + } +} + +static int blkdebug_debug_breakpoint(BlockDriverState *bs, const char *event, + const char *tag) +{ + BDRVBlkdebugState *s = bs->opaque; + struct BlkdebugRule *rule; + int blkdebug_event; + + blkdebug_event = qapi_enum_parse(&BlkdebugEvent_lookup, event, -1, NULL); + if (blkdebug_event < 0) { + return -ENOENT; + } + + rule = g_malloc(sizeof(*rule)); + *rule = (struct BlkdebugRule) { + .event = blkdebug_event, + .action = ACTION_SUSPEND, + .state = 0, + .options.suspend.tag = g_strdup(tag), + }; + + qemu_mutex_lock(&s->lock); + QLIST_INSERT_HEAD(&s->rules[blkdebug_event], rule, next); + qemu_mutex_unlock(&s->lock); + + return 0; +} + +/* Called with lock held. May temporarily release lock. */ +static int resume_req_by_tag(BDRVBlkdebugState *s, const char *tag, bool all) +{ + BlkdebugSuspendedReq *r; + +retry: + /* + * No need for _SAFE, since a different coroutine can remove another node + * (not the current one) in this list, and when the current one is removed + * the iteration starts back from beginning anyways. + */ + QLIST_FOREACH(r, &s->suspended_reqs, next) { + if (!strcmp(r->tag, tag)) { + Coroutine *co = r->co; + + if (!qtest_enabled()) { + printf("blkdebug: Resuming request '%s'\n", r->tag); + } + + QLIST_REMOVE(r, next); + g_free(r->tag); + g_free(r); + + qemu_mutex_unlock(&s->lock); + qemu_coroutine_enter(co); + qemu_mutex_lock(&s->lock); + + if (all) { + goto retry; + } + return 0; + } + } + return -ENOENT; +} + +static int blkdebug_debug_resume(BlockDriverState *bs, const char *tag) +{ + BDRVBlkdebugState *s = bs->opaque; + QEMU_LOCK_GUARD(&s->lock); + return resume_req_by_tag(s, tag, false); +} + +static int blkdebug_debug_remove_breakpoint(BlockDriverState *bs, + const char *tag) +{ + BDRVBlkdebugState *s = bs->opaque; + BlkdebugRule *rule, *next; + int i, ret = -ENOENT; + + QEMU_LOCK_GUARD(&s->lock); + for (i = 0; i < BLKDBG__MAX; i++) { + QLIST_FOREACH_SAFE(rule, &s->rules[i], next, next) { + if (rule->action == ACTION_SUSPEND && + !strcmp(rule->options.suspend.tag, tag)) { + remove_rule(rule); + ret = 0; + } + } + } + if (resume_req_by_tag(s, tag, true) == 0) { + ret = 0; + } + return ret; +} + +static bool blkdebug_debug_is_suspended(BlockDriverState *bs, const char *tag) +{ + BDRVBlkdebugState *s = bs->opaque; + BlkdebugSuspendedReq *r; + + QEMU_LOCK_GUARD(&s->lock); + QLIST_FOREACH(r, &s->suspended_reqs, next) { + if (!strcmp(r->tag, tag)) { + return true; + } + } + return false; +} + +static int64_t blkdebug_getlength(BlockDriverState *bs) +{ + return bdrv_getlength(bs->file->bs); +} + +static void blkdebug_refresh_filename(BlockDriverState *bs) +{ + BDRVBlkdebugState *s = bs->opaque; + const QDictEntry *e; + int ret; + + if (!bs->file->bs->exact_filename[0]) { + return; + } + + for (e = qdict_first(bs->full_open_options); e; + e = qdict_next(bs->full_open_options, e)) + { + /* Real child options are under "image", but "x-image" may + * contain a filename */ + if (strcmp(qdict_entry_key(e), "config") && + strcmp(qdict_entry_key(e), "image") && + strcmp(qdict_entry_key(e), "x-image") && + strcmp(qdict_entry_key(e), "driver")) + { + return; + } + } + + ret = snprintf(bs->exact_filename, sizeof(bs->exact_filename), + "blkdebug:%s:%s", + s->config_file ?: "", bs->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 void blkdebug_refresh_limits(BlockDriverState *bs, Error **errp) +{ + BDRVBlkdebugState *s = bs->opaque; + + if (s->align) { + bs->bl.request_alignment = s->align; + } + if (s->max_transfer) { + bs->bl.max_transfer = s->max_transfer; + } + if (s->opt_write_zero) { + bs->bl.pwrite_zeroes_alignment = s->opt_write_zero; + } + if (s->max_write_zero) { + bs->bl.max_pwrite_zeroes = s->max_write_zero; + } + if (s->opt_discard) { + bs->bl.pdiscard_alignment = s->opt_discard; + } + if (s->max_discard) { + bs->bl.max_pdiscard = s->max_discard; + } +} + +static int blkdebug_reopen_prepare(BDRVReopenState *reopen_state, + BlockReopenQueue *queue, Error **errp) +{ + return 0; +} + +static void blkdebug_child_perm(BlockDriverState *bs, BdrvChild *c, + BdrvChildRole role, + BlockReopenQueue *reopen_queue, + uint64_t perm, uint64_t shared, + uint64_t *nperm, uint64_t *nshared) +{ + BDRVBlkdebugState *s = bs->opaque; + + bdrv_default_perms(bs, c, role, reopen_queue, + perm, shared, nperm, nshared); + + *nperm |= s->take_child_perms; + *nshared &= ~s->unshare_child_perms; +} + +static const char *const blkdebug_strong_runtime_opts[] = { + "config", + "inject-error.", + "set-state.", + "align", + "max-transfer", + "opt-write-zero", + "max-write-zero", + "opt-discard", + "max-discard", + + NULL +}; + +static BlockDriver bdrv_blkdebug = { + .format_name = "blkdebug", + .protocol_name = "blkdebug", + .instance_size = sizeof(BDRVBlkdebugState), + .is_filter = true, + + .bdrv_parse_filename = blkdebug_parse_filename, + .bdrv_file_open = blkdebug_open, + .bdrv_close = blkdebug_close, + .bdrv_reopen_prepare = blkdebug_reopen_prepare, + .bdrv_child_perm = blkdebug_child_perm, + + .bdrv_getlength = blkdebug_getlength, + .bdrv_refresh_filename = blkdebug_refresh_filename, + .bdrv_refresh_limits = blkdebug_refresh_limits, + + .bdrv_co_preadv = blkdebug_co_preadv, + .bdrv_co_pwritev = blkdebug_co_pwritev, + .bdrv_co_flush_to_disk = blkdebug_co_flush, + .bdrv_co_pwrite_zeroes = blkdebug_co_pwrite_zeroes, + .bdrv_co_pdiscard = blkdebug_co_pdiscard, + .bdrv_co_block_status = blkdebug_co_block_status, + + .bdrv_debug_event = blkdebug_debug_event, + .bdrv_debug_breakpoint = blkdebug_debug_breakpoint, + .bdrv_debug_remove_breakpoint + = blkdebug_debug_remove_breakpoint, + .bdrv_debug_resume = blkdebug_debug_resume, + .bdrv_debug_is_suspended = blkdebug_debug_is_suspended, + + .strong_runtime_opts = blkdebug_strong_runtime_opts, +}; + +static void bdrv_blkdebug_init(void) +{ + bdrv_register(&bdrv_blkdebug); +} + +block_init(bdrv_blkdebug_init); |