This adds a function to shut down all block exports, and another one to shut down the block exports of a single type. The latter is used for now when stopping the NBD server. As soon as we implement support for multiple NBD servers, we'll need a per-server list of exports and it will be replaced by a function using that.
As a side effect, the BlockExport layer has a list tracking all existing exports now. closed_exports loses its only user and can go away. Signed-off-by: Kevin Wolf <kw...@redhat.com> --- include/block/export.h | 8 +++++++ include/block/nbd.h | 2 -- block.c | 2 +- block/export/export.c | 52 ++++++++++++++++++++++++++++++++++++++++++ blockdev-nbd.c | 2 +- nbd/server.c | 34 ++++----------------------- qemu-nbd.c | 2 +- 7 files changed, 68 insertions(+), 34 deletions(-) diff --git a/include/block/export.h b/include/block/export.h index 597fc58245..1698b68f09 100644 --- a/include/block/export.h +++ b/include/block/export.h @@ -15,6 +15,7 @@ #define BLOCK_EXPORT_H #include "qapi/qapi-types-block-export.h" +#include "qemu/queue.h" typedef struct BlockExport BlockExport; @@ -23,6 +24,7 @@ typedef struct BlockExportDriver { size_t instance_size; int (*create)(BlockExport *, BlockExportOptions *, Error **); void (*delete)(BlockExport *); + void (*request_shutdown)(BlockExport *); } BlockExportDriver; struct BlockExport { @@ -40,6 +42,9 @@ struct BlockExport { * BlockExportDriver callbacks. */ AioContext *ctx; + + /* List entry for block_exports */ + QLIST_ENTRY(BlockExport) next; }; extern const BlockExportDriver blk_exp_nbd; @@ -47,5 +52,8 @@ extern const BlockExportDriver blk_exp_nbd; BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp); void blk_exp_ref(BlockExport *exp); void blk_exp_unref(BlockExport *exp); +void blk_exp_request_shutdown(BlockExport *exp); +void blk_exp_close_all(void); +void blk_exp_close_all_type(BlockExportType type); #endif diff --git a/include/block/nbd.h b/include/block/nbd.h index 602536feb2..91a9d4f96d 100644 --- a/include/block/nbd.h +++ b/include/block/nbd.h @@ -335,12 +335,10 @@ int nbd_export_new(BlockExport *blk_exp, BlockDriverState *bs, const char *bitmap, bool readonly, bool shared, bool writethrough, Error **errp); void nbd_export_set_on_eject_blk(BlockExport *exp, BlockBackend *blk); -void nbd_export_close(NBDExport *exp); void nbd_export_remove(NBDExport *exp, NbdServerRemoveMode mode, Error **errp); AioContext *nbd_export_aio_context(NBDExport *exp); NBDExport *nbd_export_find(const char *name); -void nbd_export_close_all(void); void nbd_client_new(QIOChannelSocket *sioc, QCryptoTLSCreds *tlscreds, diff --git a/block.c b/block.c index d9ac0e07eb..357c72846e 100644 --- a/block.c +++ b/block.c @@ -4424,7 +4424,7 @@ static void bdrv_close(BlockDriverState *bs) void bdrv_close_all(void) { assert(job_next(NULL) == NULL); - nbd_export_close_all(); + blk_exp_close_all(); /* Drop references from requests still in flight, such as canceled block * jobs whose AIO context has not been polled yet */ diff --git a/block/export/export.c b/block/export/export.c index 9de108cbc1..675db9a8b9 100644 --- a/block/export/export.c +++ b/block/export/export.c @@ -24,6 +24,9 @@ static const BlockExportDriver* blk_exp_drivers[] = { &blk_exp_nbd, }; +static QLIST_HEAD(, BlockExport) block_exports = + QLIST_HEAD_INITIALIZER(block_exports); + static const BlockExportDriver *blk_exp_find_driver(BlockExportType type) { int i; @@ -60,6 +63,7 @@ BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp) return NULL; } + QLIST_INSERT_HEAD(&block_exports, exp, next); return exp; } @@ -73,11 +77,59 @@ void blk_exp_unref(BlockExport *exp) { assert(exp->refcount > 0); if (--exp->refcount == 0) { + QLIST_REMOVE(exp, next); exp->drv->delete(exp); g_free(exp); + aio_wait_kick(); } } +void blk_exp_request_shutdown(BlockExport *exp) +{ + AioContext *aio_context = exp->ctx; + + aio_context_acquire(aio_context); + exp->drv->request_shutdown(exp); + aio_context_release(aio_context); +} + +static bool blk_exp_has_type(BlockExportType type) +{ + BlockExport *exp; + + if (type == BLOCK_EXPORT_TYPE__MAX) { + return !QLIST_EMPTY(&block_exports); + } + + QLIST_FOREACH(exp, &block_exports, next) { + if (exp->drv->type == type) { + return true; + } + } + + return false; +} + +/* type == BLOCK_EXPORT_TYPE__MAX for all types */ +void blk_exp_close_all_type(BlockExportType type) +{ + BlockExport *exp, *next; + + QLIST_FOREACH_SAFE(exp, &block_exports, next, next) { + if (type != BLOCK_EXPORT_TYPE__MAX && exp->drv->type != type) { + continue; + } + blk_exp_request_shutdown(exp); + } + + AIO_WAIT_WHILE(NULL, blk_exp_has_type(type)); +} + +void blk_exp_close_all(void) +{ + blk_exp_close_all_type(BLOCK_EXPORT_TYPE__MAX); +} + void qmp_block_export_add(BlockExportOptions *export, Error **errp) { blk_exp_add(export, errp); diff --git a/blockdev-nbd.c b/blockdev-nbd.c index f97deba424..1c7aa874ee 100644 --- a/blockdev-nbd.c +++ b/blockdev-nbd.c @@ -277,7 +277,7 @@ void qmp_nbd_server_stop(Error **errp) return; } - nbd_export_close_all(); + blk_exp_close_all_type(BLOCK_EXPORT_TYPE_NBD); nbd_server_free(nbd_server); nbd_server = NULL; diff --git a/nbd/server.c b/nbd/server.c index 6a58297557..7e2976b81d 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -100,8 +100,6 @@ struct NBDExport { }; static QTAILQ_HEAD(, NBDExport) exports = QTAILQ_HEAD_INITIALIZER(exports); -static QTAILQ_HEAD(, NBDExport) closed_exports = - QTAILQ_HEAD_INITIALIZER(closed_exports); /* NBDExportMetaContexts represents a list of contexts to be exported, * as selected by NBD_OPT_SET_META_CONTEXT. Also used for @@ -1494,12 +1492,8 @@ static void blk_aio_detach(void *opaque) static void nbd_eject_notifier(Notifier *n, void *data) { NBDExport *exp = container_of(n, NBDExport, eject_notifier); - AioContext *aio_context; - aio_context = exp->common.ctx; - aio_context_acquire(aio_context); - nbd_export_close(exp); - aio_context_release(aio_context); + blk_exp_request_shutdown(&exp->common); } void nbd_export_set_on_eject_blk(BlockExport *exp, BlockBackend *blk) @@ -1652,8 +1646,9 @@ nbd_export_aio_context(NBDExport *exp) return exp->common.ctx; } -void nbd_export_close(NBDExport *exp) +static void nbd_export_request_shutdown(BlockExport *blk_exp) { + NBDExport *exp = container_of(blk_exp, NBDExport, common); NBDClient *client, *next; blk_exp_ref(&exp->common); @@ -1672,7 +1667,6 @@ void nbd_export_close(NBDExport *exp) g_free(exp->name); exp->name = NULL; QTAILQ_REMOVE(&exports, exp, next); - QTAILQ_INSERT_TAIL(&closed_exports, exp, next); } blk_exp_unref(&exp->common); } @@ -1681,7 +1675,7 @@ void nbd_export_remove(NBDExport *exp, NbdServerRemoveMode mode, Error **errp) { ERRP_GUARD(); if (mode == NBD_SERVER_REMOVE_MODE_HARD || QTAILQ_EMPTY(&exp->clients)) { - nbd_export_close(exp); + nbd_export_request_shutdown(&exp->common); return; } @@ -1716,9 +1710,6 @@ static void nbd_export_delete(BlockExport *blk_exp) bdrv_dirty_bitmap_set_busy(exp->export_bitmap, false); g_free(exp->export_bitmap_context); } - - QTAILQ_REMOVE(&closed_exports, exp, next); - aio_wait_kick(); } const BlockExportDriver blk_exp_nbd = { @@ -1726,24 +1717,9 @@ const BlockExportDriver blk_exp_nbd = { .instance_size = sizeof(NBDExport), .create = nbd_export_create, .delete = nbd_export_delete, + .request_shutdown = nbd_export_request_shutdown, }; -void nbd_export_close_all(void) -{ - NBDExport *exp, *next; - AioContext *aio_context; - - QTAILQ_FOREACH_SAFE(exp, &exports, next, next) { - aio_context = exp->common.ctx; - aio_context_acquire(aio_context); - nbd_export_close(exp); - aio_context_release(aio_context); - } - - AIO_WAIT_WHILE(NULL, !(QTAILQ_EMPTY(&exports) && - QTAILQ_EMPTY(&closed_exports))); -} - static int coroutine_fn nbd_co_send_iov(NBDClient *client, struct iovec *iov, unsigned niov, Error **errp) { diff --git a/qemu-nbd.c b/qemu-nbd.c index f31868708c..939a08902a 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -1110,7 +1110,7 @@ int main(int argc, char **argv) do { main_loop_wait(false); if (state == TERMINATE) { - nbd_export_close_all(); + blk_exp_close_all(); state = TERMINATED; } } while (state != TERMINATED); -- 2.25.4