]> www.infradead.org Git - users/jedix/linux-maple.git/commitdiff
selftests: ublk: add kernel selftests for ublk
authorMing Lei <ming.lei@redhat.com>
Fri, 28 Feb 2025 16:19:14 +0000 (00:19 +0800)
committerJens Axboe <axboe@kernel.dk>
Fri, 28 Feb 2025 16:28:08 +0000 (09:28 -0700)
Both ublk driver and userspace heavily depends on io_uring subsystem,
and tools/testing/selftests/ should be the best place for holding this
cross-subsystem tests.

Add basic read/write IO test over this ublk null disk, and make sure ublk
working.

More tests will be added.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250228161919.2869102-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
MAINTAINERS
tools/testing/selftests/Makefile
tools/testing/selftests/ublk/.gitignore [new file with mode: 0644]
tools/testing/selftests/ublk/Makefile [new file with mode: 0644]
tools/testing/selftests/ublk/config [new file with mode: 0644]
tools/testing/selftests/ublk/kublk.c [new file with mode: 0644]
tools/testing/selftests/ublk/kublk.h [new file with mode: 0644]
tools/testing/selftests/ublk/null.c [new file with mode: 0644]
tools/testing/selftests/ublk/test_common.sh [new file with mode: 0755]
tools/testing/selftests/ublk/test_null_01.sh [new file with mode: 0755]

index efee40ea589f70bc5e4a390072a4543234616743..7dd2fbfc8604d9fbf7e523d01819be39a189d229 100644 (file)
@@ -24237,6 +24237,7 @@ S:      Maintained
 F:     Documentation/block/ublk.rst
 F:     drivers/block/ublk_drv.c
 F:     include/uapi/linux/ublk_cmd.h
+F:     tools/testing/selftests/ublk/
 
 UBSAN
 M:     Kees Cook <kees@kernel.org>
index 8daac70c2f9d2c41be51f421b9c1e27eeee8bede..52ba0eb5eaa7c46d47b7f532cd0fc8ed1c96ee84 100644 (file)
@@ -113,6 +113,7 @@ endif
 TARGETS += tmpfs
 TARGETS += tpm2
 TARGETS += tty
+TARGETS += ublk
 TARGETS += uevent
 TARGETS += user_events
 TARGETS += vDSO
diff --git a/tools/testing/selftests/ublk/.gitignore b/tools/testing/selftests/ublk/.gitignore
new file mode 100644 (file)
index 0000000..8b2871e
--- /dev/null
@@ -0,0 +1,3 @@
+kublk
+/tools
+*-verify.state
diff --git a/tools/testing/selftests/ublk/Makefile b/tools/testing/selftests/ublk/Makefile
new file mode 100644 (file)
index 0000000..b6ac306
--- /dev/null
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0
+
+CFLAGS += -O3 -Wl,-no-as-needed -Wall -I $(top_srcdir)
+LDLIBS += -lpthread -lm -luring
+
+TEST_PROGS := test_null_01.sh
+
+TEST_GEN_PROGS_EXTENDED = kublk
+
+include ../lib.mk
+
+$(TEST_GEN_PROGS_EXTENDED): kublk.c null.c
diff --git a/tools/testing/selftests/ublk/config b/tools/testing/selftests/ublk/config
new file mode 100644 (file)
index 0000000..592b0ba
--- /dev/null
@@ -0,0 +1 @@
+CONFIG_BLK_DEV_UBLK=m
diff --git a/tools/testing/selftests/ublk/kublk.c b/tools/testing/selftests/ublk/kublk.c
new file mode 100644 (file)
index 0000000..b2dfd35
--- /dev/null
@@ -0,0 +1,1081 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Description: uring_cmd based ublk
+ */
+
+#include "kublk.h"
+
+unsigned int ublk_dbg_mask = UBLK_LOG;
+static const struct ublk_tgt_ops *tgt_ops_list[] = {
+       &null_tgt_ops,
+};
+
+static const struct ublk_tgt_ops *ublk_find_tgt(const char *name)
+{
+       const struct ublk_tgt_ops *ops;
+       int i;
+
+       if (name == NULL)
+               return NULL;
+
+       for (i = 0; sizeof(tgt_ops_list) / sizeof(ops); i++)
+               if (strcmp(tgt_ops_list[i]->name, name) == 0)
+                       return tgt_ops_list[i];
+       return NULL;
+}
+
+static inline int ublk_setup_ring(struct io_uring *r, int depth,
+               int cq_depth, unsigned flags)
+{
+       struct io_uring_params p;
+
+       memset(&p, 0, sizeof(p));
+       p.flags = flags | IORING_SETUP_CQSIZE;
+       p.cq_entries = cq_depth;
+
+       return io_uring_queue_init_params(depth, r, &p);
+}
+
+static void ublk_ctrl_init_cmd(struct ublk_dev *dev,
+               struct io_uring_sqe *sqe,
+               struct ublk_ctrl_cmd_data *data)
+{
+       struct ublksrv_ctrl_dev_info *info = &dev->dev_info;
+       struct ublksrv_ctrl_cmd *cmd = (struct ublksrv_ctrl_cmd *)ublk_get_sqe_cmd(sqe);
+
+       sqe->fd = dev->ctrl_fd;
+       sqe->opcode = IORING_OP_URING_CMD;
+       sqe->ioprio = 0;
+
+       if (data->flags & CTRL_CMD_HAS_BUF) {
+               cmd->addr = data->addr;
+               cmd->len = data->len;
+       }
+
+       if (data->flags & CTRL_CMD_HAS_DATA)
+               cmd->data[0] = data->data[0];
+
+       cmd->dev_id = info->dev_id;
+       cmd->queue_id = -1;
+
+       ublk_set_sqe_cmd_op(sqe, data->cmd_op);
+
+       io_uring_sqe_set_data(sqe, cmd);
+}
+
+static int __ublk_ctrl_cmd(struct ublk_dev *dev,
+               struct ublk_ctrl_cmd_data *data)
+{
+       struct io_uring_sqe *sqe;
+       struct io_uring_cqe *cqe;
+       int ret = -EINVAL;
+
+       sqe = io_uring_get_sqe(&dev->ring);
+       if (!sqe) {
+               ublk_err("%s: can't get sqe ret %d\n", __func__, ret);
+               return ret;
+       }
+
+       ublk_ctrl_init_cmd(dev, sqe, data);
+
+       ret = io_uring_submit(&dev->ring);
+       if (ret < 0) {
+               ublk_err("uring submit ret %d\n", ret);
+               return ret;
+       }
+
+       ret = io_uring_wait_cqe(&dev->ring, &cqe);
+       if (ret < 0) {
+               ublk_err("wait cqe: %s\n", strerror(-ret));
+               return ret;
+       }
+       io_uring_cqe_seen(&dev->ring, cqe);
+
+       return cqe->res;
+}
+
+static int ublk_ctrl_stop_dev(struct ublk_dev *dev)
+{
+       struct ublk_ctrl_cmd_data data = {
+               .cmd_op = UBLK_CMD_STOP_DEV,
+       };
+
+       return __ublk_ctrl_cmd(dev, &data);
+}
+
+static int ublk_ctrl_start_dev(struct ublk_dev *dev,
+               int daemon_pid)
+{
+       struct ublk_ctrl_cmd_data data = {
+               .cmd_op = UBLK_U_CMD_START_DEV,
+               .flags  = CTRL_CMD_HAS_DATA,
+       };
+
+       dev->dev_info.ublksrv_pid = data.data[0] = daemon_pid;
+
+       return __ublk_ctrl_cmd(dev, &data);
+}
+
+static int ublk_ctrl_add_dev(struct ublk_dev *dev)
+{
+       struct ublk_ctrl_cmd_data data = {
+               .cmd_op = UBLK_U_CMD_ADD_DEV,
+               .flags  = CTRL_CMD_HAS_BUF,
+               .addr = (__u64) (uintptr_t) &dev->dev_info,
+               .len = sizeof(struct ublksrv_ctrl_dev_info),
+       };
+
+       return __ublk_ctrl_cmd(dev, &data);
+}
+
+static int ublk_ctrl_del_dev(struct ublk_dev *dev)
+{
+       struct ublk_ctrl_cmd_data data = {
+               .cmd_op = UBLK_U_CMD_DEL_DEV,
+               .flags = 0,
+       };
+
+       return __ublk_ctrl_cmd(dev, &data);
+}
+
+static int ublk_ctrl_get_info(struct ublk_dev *dev)
+{
+       struct ublk_ctrl_cmd_data data = {
+               .cmd_op = UBLK_U_CMD_GET_DEV_INFO,
+               .flags  = CTRL_CMD_HAS_BUF,
+               .addr = (__u64) (uintptr_t) &dev->dev_info,
+               .len = sizeof(struct ublksrv_ctrl_dev_info),
+       };
+
+       return __ublk_ctrl_cmd(dev, &data);
+}
+
+static int ublk_ctrl_set_params(struct ublk_dev *dev,
+               struct ublk_params *params)
+{
+       struct ublk_ctrl_cmd_data data = {
+               .cmd_op = UBLK_U_CMD_SET_PARAMS,
+               .flags  = CTRL_CMD_HAS_BUF,
+               .addr = (__u64) (uintptr_t) params,
+               .len = sizeof(*params),
+       };
+       params->len = sizeof(*params);
+       return __ublk_ctrl_cmd(dev, &data);
+}
+
+static int ublk_ctrl_get_params(struct ublk_dev *dev,
+               struct ublk_params *params)
+{
+       struct ublk_ctrl_cmd_data data = {
+               .cmd_op = UBLK_CMD_GET_PARAMS,
+               .flags  = CTRL_CMD_HAS_BUF,
+               .addr = (__u64)params,
+               .len = sizeof(*params),
+       };
+
+       params->len = sizeof(*params);
+
+       return __ublk_ctrl_cmd(dev, &data);
+}
+
+static int ublk_ctrl_get_features(struct ublk_dev *dev,
+               __u64 *features)
+{
+       struct ublk_ctrl_cmd_data data = {
+               .cmd_op = UBLK_U_CMD_GET_FEATURES,
+               .flags  = CTRL_CMD_HAS_BUF,
+               .addr = (__u64) (uintptr_t) features,
+               .len = sizeof(*features),
+       };
+
+       return __ublk_ctrl_cmd(dev, &data);
+}
+
+static const char *ublk_dev_state_desc(struct ublk_dev *dev)
+{
+       switch (dev->dev_info.state) {
+       case UBLK_S_DEV_DEAD:
+               return "DEAD";
+       case UBLK_S_DEV_LIVE:
+               return "LIVE";
+       case UBLK_S_DEV_QUIESCED:
+               return "QUIESCED";
+       default:
+               return "UNKNOWN";
+       };
+}
+
+static void ublk_ctrl_dump(struct ublk_dev *dev)
+{
+       struct ublksrv_ctrl_dev_info *info = &dev->dev_info;
+       struct ublk_params p;
+       int ret;
+
+       ret = ublk_ctrl_get_params(dev, &p);
+       if (ret < 0) {
+               ublk_err("failed to get params %m\n");
+               return;
+       }
+
+       ublk_log("dev id %d: nr_hw_queues %d queue_depth %d block size %d dev_capacity %lld\n",
+                       info->dev_id, info->nr_hw_queues, info->queue_depth,
+                       1 << p.basic.logical_bs_shift, p.basic.dev_sectors);
+       ublk_log("\tmax rq size %d daemon pid %d flags 0x%llx state %s\n",
+                       info->max_io_buf_bytes, info->ublksrv_pid, info->flags,
+                       ublk_dev_state_desc(dev));
+       fflush(stdout);
+}
+
+static void ublk_ctrl_deinit(struct ublk_dev *dev)
+{
+       close(dev->ctrl_fd);
+       free(dev);
+}
+
+static struct ublk_dev *ublk_ctrl_init(void)
+{
+       struct ublk_dev *dev = (struct ublk_dev *)calloc(1, sizeof(*dev));
+       struct ublksrv_ctrl_dev_info *info = &dev->dev_info;
+       int ret;
+
+       dev->ctrl_fd = open(CTRL_DEV, O_RDWR);
+       if (dev->ctrl_fd < 0) {
+               free(dev);
+               return NULL;
+       }
+
+       info->max_io_buf_bytes = UBLK_IO_MAX_BYTES;
+
+       ret = ublk_setup_ring(&dev->ring, UBLK_CTRL_RING_DEPTH,
+                       UBLK_CTRL_RING_DEPTH, IORING_SETUP_SQE128);
+       if (ret < 0) {
+               ublk_err("queue_init: %s\n", strerror(-ret));
+               free(dev);
+               return NULL;
+       }
+       dev->nr_fds = 1;
+
+       return dev;
+}
+
+static int __ublk_queue_cmd_buf_sz(unsigned depth)
+{
+       int size =  depth * sizeof(struct ublksrv_io_desc);
+       unsigned int page_sz = getpagesize();
+
+       return round_up(size, page_sz);
+}
+
+static int ublk_queue_max_cmd_buf_sz(void)
+{
+       return __ublk_queue_cmd_buf_sz(UBLK_MAX_QUEUE_DEPTH);
+}
+
+static int ublk_queue_cmd_buf_sz(struct ublk_queue *q)
+{
+       return __ublk_queue_cmd_buf_sz(q->q_depth);
+}
+
+static void ublk_queue_deinit(struct ublk_queue *q)
+{
+       int i;
+       int nr_ios = q->q_depth;
+
+       io_uring_unregister_ring_fd(&q->ring);
+
+       if (q->ring.ring_fd > 0) {
+               io_uring_unregister_files(&q->ring);
+               close(q->ring.ring_fd);
+               q->ring.ring_fd = -1;
+       }
+
+       if (q->io_cmd_buf)
+               munmap(q->io_cmd_buf, ublk_queue_cmd_buf_sz(q));
+
+       for (i = 0; i < nr_ios; i++)
+               free(q->ios[i].buf_addr);
+}
+
+static int ublk_queue_init(struct ublk_queue *q)
+{
+       struct ublk_dev *dev = q->dev;
+       int depth = dev->dev_info.queue_depth;
+       int i, ret = -1;
+       int cmd_buf_size, io_buf_size;
+       unsigned long off;
+       int ring_depth = dev->tgt.sq_depth, cq_depth = dev->tgt.cq_depth;
+
+       q->tgt_ops = dev->tgt.ops;
+       q->state = 0;
+       q->q_depth = depth;
+       q->cmd_inflight = 0;
+       q->tid = gettid();
+
+       cmd_buf_size = ublk_queue_cmd_buf_sz(q);
+       off = UBLKSRV_CMD_BUF_OFFSET + q->q_id * ublk_queue_max_cmd_buf_sz();
+       q->io_cmd_buf = (char *)mmap(0, cmd_buf_size, PROT_READ,
+                       MAP_SHARED | MAP_POPULATE, dev->fds[0], off);
+       if (q->io_cmd_buf == MAP_FAILED) {
+               ublk_err("ublk dev %d queue %d map io_cmd_buf failed %m\n",
+                               q->dev->dev_info.dev_id, q->q_id);
+               goto fail;
+       }
+
+       io_buf_size = dev->dev_info.max_io_buf_bytes;
+       for (i = 0; i < q->q_depth; i++) {
+               q->ios[i].buf_addr = NULL;
+               q->ios[i].flags = UBLKSRV_NEED_FETCH_RQ | UBLKSRV_IO_FREE;
+
+               if (q->state & UBLKSRV_NO_BUF)
+                       continue;
+
+               if (posix_memalign((void **)&q->ios[i].buf_addr,
+                                       getpagesize(), io_buf_size)) {
+                       ublk_err("ublk dev %d queue %d io %d posix_memalign failed %m\n",
+                                       dev->dev_info.dev_id, q->q_id, i);
+                       goto fail;
+               }
+       }
+
+       ret = ublk_setup_ring(&q->ring, ring_depth, cq_depth,
+                       IORING_SETUP_COOP_TASKRUN);
+       if (ret < 0) {
+               ublk_err("ublk dev %d queue %d setup io_uring failed %d\n",
+                               q->dev->dev_info.dev_id, q->q_id, ret);
+               goto fail;
+       }
+
+       io_uring_register_ring_fd(&q->ring);
+
+       ret = io_uring_register_files(&q->ring, dev->fds, dev->nr_fds);
+       if (ret) {
+               ublk_err("ublk dev %d queue %d register files failed %d\n",
+                               q->dev->dev_info.dev_id, q->q_id, ret);
+               goto fail;
+       }
+
+       return 0;
+ fail:
+       ublk_queue_deinit(q);
+       ublk_err("ublk dev %d queue %d failed\n",
+                       dev->dev_info.dev_id, q->q_id);
+       return -ENOMEM;
+}
+
+static int ublk_dev_prep(struct ublk_dev *dev)
+{
+       int dev_id = dev->dev_info.dev_id;
+       char buf[64];
+       int ret = 0;
+
+       snprintf(buf, 64, "%s%d", UBLKC_DEV, dev_id);
+       dev->fds[0] = open(buf, O_RDWR);
+       if (dev->fds[0] < 0) {
+               ret = -EBADF;
+               ublk_err("can't open %s, ret %d\n", buf, dev->fds[0]);
+               goto fail;
+       }
+
+       if (dev->tgt.ops->init_tgt)
+               ret = dev->tgt.ops->init_tgt(dev);
+
+       return ret;
+fail:
+       close(dev->fds[0]);
+       return ret;
+}
+
+static void ublk_dev_unprep(struct ublk_dev *dev)
+{
+       if (dev->tgt.ops->deinit_tgt)
+               dev->tgt.ops->deinit_tgt(dev);
+       close(dev->fds[0]);
+}
+
+int ublk_queue_io_cmd(struct ublk_queue *q, struct ublk_io *io, unsigned tag)
+{
+       struct ublksrv_io_cmd *cmd;
+       struct io_uring_sqe *sqe;
+       unsigned int cmd_op = 0;
+       __u64 user_data;
+
+       /* only freed io can be issued */
+       if (!(io->flags & UBLKSRV_IO_FREE))
+               return 0;
+
+       /* we issue because we need either fetching or committing */
+       if (!(io->flags &
+               (UBLKSRV_NEED_FETCH_RQ | UBLKSRV_NEED_COMMIT_RQ_COMP)))
+               return 0;
+
+       if (io->flags & UBLKSRV_NEED_COMMIT_RQ_COMP)
+               cmd_op = UBLK_U_IO_COMMIT_AND_FETCH_REQ;
+       else if (io->flags & UBLKSRV_NEED_FETCH_RQ)
+               cmd_op = UBLK_U_IO_FETCH_REQ;
+
+       if (io_uring_sq_space_left(&q->ring) < 1)
+               io_uring_submit(&q->ring);
+
+       sqe = ublk_queue_alloc_sqe(q);
+       if (!sqe) {
+               ublk_err("%s: run out of sqe %d, tag %d\n",
+                               __func__, q->q_id, tag);
+               return -1;
+       }
+
+       cmd = (struct ublksrv_io_cmd *)ublk_get_sqe_cmd(sqe);
+
+       if (cmd_op == UBLK_U_IO_COMMIT_AND_FETCH_REQ)
+               cmd->result = io->result;
+
+       /* These fields should be written once, never change */
+       ublk_set_sqe_cmd_op(sqe, cmd_op);
+       sqe->fd         = 0;    /* dev->fds[0] */
+       sqe->opcode     = IORING_OP_URING_CMD;
+       sqe->flags      = IOSQE_FIXED_FILE;
+       sqe->rw_flags   = 0;
+       cmd->tag        = tag;
+       cmd->q_id       = q->q_id;
+       if (!(q->state & UBLKSRV_NO_BUF))
+               cmd->addr       = (__u64) (uintptr_t) io->buf_addr;
+       else
+               cmd->addr       = 0;
+
+       user_data = build_user_data(tag, _IOC_NR(cmd_op), 0, 0);
+       io_uring_sqe_set_data64(sqe, user_data);
+
+       io->flags = 0;
+
+       q->cmd_inflight += 1;
+
+       ublk_dbg(UBLK_DBG_IO_CMD, "%s: (qid %d tag %u cmd_op %u) iof %x stopping %d\n",
+                       __func__, q->q_id, tag, cmd_op,
+                       io->flags, !!(q->state & UBLKSRV_QUEUE_STOPPING));
+       return 1;
+}
+
+static void ublk_submit_fetch_commands(struct ublk_queue *q)
+{
+       int i = 0;
+
+       for (i = 0; i < q->q_depth; i++)
+               ublk_queue_io_cmd(q, &q->ios[i], i);
+}
+
+static int ublk_queue_is_idle(struct ublk_queue *q)
+{
+       return !io_uring_sq_ready(&q->ring) && !q->io_inflight;
+}
+
+static int ublk_queue_is_done(struct ublk_queue *q)
+{
+       return (q->state & UBLKSRV_QUEUE_STOPPING) && ublk_queue_is_idle(q);
+}
+
+static inline void ublksrv_handle_tgt_cqe(struct ublk_queue *q,
+               struct io_uring_cqe *cqe)
+{
+       unsigned tag = user_data_to_tag(cqe->user_data);
+
+       if (cqe->res < 0 && cqe->res != -EAGAIN)
+               ublk_err("%s: failed tgt io: res %d qid %u tag %u, cmd_op %u\n",
+                       __func__, cqe->res, q->q_id,
+                       user_data_to_tag(cqe->user_data),
+                       user_data_to_op(cqe->user_data));
+
+       if (q->tgt_ops->tgt_io_done)
+               q->tgt_ops->tgt_io_done(q, tag, cqe);
+}
+
+static void ublk_handle_cqe(struct io_uring *r,
+               struct io_uring_cqe *cqe, void *data)
+{
+       struct ublk_queue *q = container_of(r, struct ublk_queue, ring);
+       unsigned tag = user_data_to_tag(cqe->user_data);
+       unsigned cmd_op = user_data_to_op(cqe->user_data);
+       int fetch = (cqe->res != UBLK_IO_RES_ABORT) &&
+               !(q->state & UBLKSRV_QUEUE_STOPPING);
+       struct ublk_io *io;
+
+       if (cqe->res < 0 && cqe->res != -ENODEV)
+               ublk_err("%s: res %d userdata %llx queue state %x\n", __func__,
+                               cqe->res, cqe->user_data, q->state);
+
+       ublk_dbg(UBLK_DBG_IO_CMD, "%s: res %d (qid %d tag %u cmd_op %u target %d) stopping %d\n",
+                       __func__, cqe->res, q->q_id, tag, cmd_op,
+                       is_target_io(cqe->user_data),
+                       (q->state & UBLKSRV_QUEUE_STOPPING));
+
+       /* Don't retrieve io in case of target io */
+       if (is_target_io(cqe->user_data)) {
+               ublksrv_handle_tgt_cqe(q, cqe);
+               return;
+       }
+
+       io = &q->ios[tag];
+       q->cmd_inflight--;
+
+       if (!fetch) {
+               q->state |= UBLKSRV_QUEUE_STOPPING;
+               io->flags &= ~UBLKSRV_NEED_FETCH_RQ;
+       }
+
+       if (cqe->res == UBLK_IO_RES_OK) {
+               assert(tag < q->q_depth);
+               if (q->tgt_ops->queue_io)
+                       q->tgt_ops->queue_io(q, tag);
+       } else {
+               /*
+                * COMMIT_REQ will be completed immediately since no fetching
+                * piggyback is required.
+                *
+                * Marking IO_FREE only, then this io won't be issued since
+                * we only issue io with (UBLKSRV_IO_FREE | UBLKSRV_NEED_*)
+                *
+                * */
+               io->flags = UBLKSRV_IO_FREE;
+       }
+}
+
+static int ublk_reap_events_uring(struct io_uring *r)
+{
+       struct io_uring_cqe *cqe;
+       unsigned head;
+       int count = 0;
+
+       io_uring_for_each_cqe(r, head, cqe) {
+               ublk_handle_cqe(r, cqe, NULL);
+               count += 1;
+       }
+       io_uring_cq_advance(r, count);
+
+       return count;
+}
+
+static int ublk_process_io(struct ublk_queue *q)
+{
+       int ret, reapped;
+
+       ublk_dbg(UBLK_DBG_QUEUE, "dev%d-q%d: to_submit %d inflight cmd %u stopping %d\n",
+                               q->dev->dev_info.dev_id,
+                               q->q_id, io_uring_sq_ready(&q->ring),
+                               q->cmd_inflight,
+                               (q->state & UBLKSRV_QUEUE_STOPPING));
+
+       if (ublk_queue_is_done(q))
+               return -ENODEV;
+
+       ret = io_uring_submit_and_wait(&q->ring, 1);
+       reapped = ublk_reap_events_uring(&q->ring);
+
+       ublk_dbg(UBLK_DBG_QUEUE, "submit result %d, reapped %d stop %d idle %d\n",
+                       ret, reapped, (q->state & UBLKSRV_QUEUE_STOPPING),
+                       (q->state & UBLKSRV_QUEUE_IDLE));
+
+       return reapped;
+}
+
+static void *ublk_io_handler_fn(void *data)
+{
+       struct ublk_queue *q = data;
+       int dev_id = q->dev->dev_info.dev_id;
+       int ret;
+
+       ret = ublk_queue_init(q);
+       if (ret) {
+               ublk_err("ublk dev %d queue %d init queue failed\n",
+                               dev_id, q->q_id);
+               return NULL;
+       }
+       ublk_dbg(UBLK_DBG_QUEUE, "tid %d: ublk dev %d queue %d started\n",
+                       q->tid, dev_id, q->q_id);
+
+       /* submit all io commands to ublk driver */
+       ublk_submit_fetch_commands(q);
+       do {
+               if (ublk_process_io(q) < 0)
+                       break;
+       } while (1);
+
+       ublk_dbg(UBLK_DBG_QUEUE, "ublk dev %d queue %d exited\n", dev_id, q->q_id);
+       ublk_queue_deinit(q);
+       return NULL;
+}
+
+static void ublk_set_parameters(struct ublk_dev *dev)
+{
+       int ret;
+
+       ret = ublk_ctrl_set_params(dev, &dev->tgt.params);
+       if (ret)
+               ublk_err("dev %d set basic parameter failed %d\n",
+                               dev->dev_info.dev_id, ret);
+}
+
+static int ublk_send_dev_event(const struct dev_ctx *ctx, int dev_id)
+{
+       uint64_t id;
+       int evtfd = ctx->_evtfd;
+
+       if (evtfd < 0)
+               return -EBADF;
+
+       if (dev_id >= 0)
+               id = dev_id + 1;
+       else
+               id = ERROR_EVTFD_DEVID;
+
+       if (write(evtfd, &id, sizeof(id)) != sizeof(id))
+               return -EINVAL;
+
+       return 0;
+}
+
+
+static int ublk_start_daemon(const struct dev_ctx *ctx, struct ublk_dev *dev)
+{
+       int ret, i;
+       void *thread_ret;
+       const struct ublksrv_ctrl_dev_info *dinfo = &dev->dev_info;
+
+       ublk_dbg(UBLK_DBG_DEV, "%s enter\n", __func__);
+
+       ret = ublk_dev_prep(dev);
+       if (ret)
+               return ret;
+
+       for (i = 0; i < dinfo->nr_hw_queues; i++) {
+               dev->q[i].dev = dev;
+               dev->q[i].q_id = i;
+               pthread_create(&dev->q[i].thread, NULL,
+                               ublk_io_handler_fn,
+                               &dev->q[i]);
+       }
+
+       /* everything is fine now, start us */
+       ublk_set_parameters(dev);
+       ret = ublk_ctrl_start_dev(dev, getpid());
+       if (ret < 0) {
+               ublk_err("%s: ublk_ctrl_start_dev failed: %d\n", __func__, ret);
+               goto fail;
+       }
+
+       ublk_ctrl_get_info(dev);
+       ublk_send_dev_event(ctx, dev->dev_info.dev_id);
+
+       /* wait until we are terminated */
+       for (i = 0; i < dinfo->nr_hw_queues; i++)
+               pthread_join(dev->q[i].thread, &thread_ret);
+ fail:
+       ublk_dev_unprep(dev);
+       ublk_dbg(UBLK_DBG_DEV, "%s exit\n", __func__);
+
+       return ret;
+}
+
+static int wait_ublk_dev(char *dev_name, int evt_mask, unsigned timeout)
+{
+#define EV_SIZE (sizeof(struct inotify_event))
+#define EV_BUF_LEN (128 * (EV_SIZE + 16))
+       struct pollfd pfd;
+       int fd, wd;
+       int ret = -EINVAL;
+
+       fd = inotify_init();
+       if (fd < 0) {
+               ublk_dbg(UBLK_DBG_DEV, "%s: inotify init failed\n", __func__);
+               return fd;
+       }
+
+       wd = inotify_add_watch(fd, "/dev", evt_mask);
+       if (wd == -1) {
+               ublk_dbg(UBLK_DBG_DEV, "%s: add watch for /dev failed\n", __func__);
+               goto fail;
+       }
+
+       pfd.fd = fd;
+       pfd.events = POLL_IN;
+       while (1) {
+               int i = 0;
+               char buffer[EV_BUF_LEN];
+               ret = poll(&pfd, 1, 1000 * timeout);
+
+               if (ret == -1) {
+                       ublk_err("%s: poll inotify failed: %d\n", __func__, ret);
+                       goto rm_watch;
+               } else if (ret == 0) {
+                       ublk_err("%s: poll inotify timeout\n", __func__);
+                       ret = -ETIMEDOUT;
+                       goto rm_watch;
+               }
+
+               ret = read(fd, buffer, EV_BUF_LEN);
+               if (ret < 0) {
+                       ublk_err("%s: read inotify fd failed\n", __func__);
+                       goto rm_watch;
+               }
+
+               while (i < ret) {
+                       struct inotify_event *event = (struct inotify_event *)&buffer[i];
+
+                       ublk_dbg(UBLK_DBG_DEV, "%s: inotify event %x %s\n",
+                                       __func__, event->mask, event->name);
+                       if (event->mask & evt_mask) {
+                               if (!strcmp(event->name, dev_name)) {
+                                       ret = 0;
+                                       goto rm_watch;
+                               }
+                       }
+                       i += EV_SIZE + event->len;
+               }
+       }
+rm_watch:
+       inotify_rm_watch(fd, wd);
+fail:
+       close(fd);
+       return ret;
+}
+
+static int ublk_stop_io_daemon(const struct ublk_dev *dev)
+{
+       int daemon_pid = dev->dev_info.ublksrv_pid;
+       int dev_id = dev->dev_info.dev_id;
+       char ublkc[64];
+       int ret = 0;
+
+       /* daemon may be dead already */
+       if (kill(daemon_pid, 0) < 0)
+               goto wait;
+
+       /*
+        * Wait until ublk char device is closed, when our daemon is shutdown
+        */
+       snprintf(ublkc, sizeof(ublkc), "%s%d", "ublkc", dev_id);
+       ret = wait_ublk_dev(ublkc, IN_CLOSE_WRITE, 10);
+       /* double check and inotify may not be 100% reliable */
+       if (ret == -ETIMEDOUT)
+               /* the daemon doesn't exist now if kill(0) fails */
+               ret = kill(daemon_pid, 0) < 0;
+wait:
+       waitpid(daemon_pid, NULL, 0);
+       ublk_dbg(UBLK_DBG_DEV, "%s: pid %d dev_id %d ret %d\n",
+                       __func__, daemon_pid, dev_id, ret);
+
+       return ret;
+}
+
+static int __cmd_dev_add(const struct dev_ctx *ctx)
+{
+       unsigned nr_queues = ctx->nr_hw_queues;
+       const char *tgt_type = ctx->tgt_type;
+       unsigned depth = ctx->queue_depth;
+       __u64 features;
+       const struct ublk_tgt_ops *ops;
+       struct ublksrv_ctrl_dev_info *info;
+       struct ublk_dev *dev;
+       int dev_id = ctx->dev_id;
+       int ret;
+
+       ops = ublk_find_tgt(tgt_type);
+       if (!ops) {
+               ublk_err("%s: no such tgt type, type %s\n",
+                               __func__, tgt_type);
+               return -ENODEV;
+       }
+
+       if (nr_queues > UBLK_MAX_QUEUES || depth > UBLK_QUEUE_DEPTH) {
+               ublk_err("%s: invalid nr_queues or depth queues %u depth %u\n",
+                               __func__, nr_queues, depth);
+               return -EINVAL;
+       }
+
+       dev = ublk_ctrl_init();
+       if (!dev) {
+               ublk_err("%s: can't alloc dev id %d, type %s\n",
+                               __func__, dev_id, tgt_type);
+               return -ENOMEM;
+       }
+
+       /* kernel doesn't support get_features */
+       ret = ublk_ctrl_get_features(dev, &features);
+       if (ret < 0)
+               return -EINVAL;
+
+       if (!(features & UBLK_F_CMD_IOCTL_ENCODE))
+               return -ENOTSUP;
+
+       info = &dev->dev_info;
+       info->dev_id = ctx->dev_id;
+       info->nr_hw_queues = nr_queues;
+       info->queue_depth = depth;
+       info->flags = ctx->flags;
+       dev->tgt.ops = ops;
+       dev->tgt.sq_depth = depth;
+       dev->tgt.cq_depth = depth;
+
+       ret = ublk_ctrl_add_dev(dev);
+       if (ret < 0) {
+               ublk_err("%s: can't add dev id %d, type %s ret %d\n",
+                               __func__, dev_id, tgt_type, ret);
+               goto fail;
+       }
+
+       ret = ublk_start_daemon(ctx, dev);
+       ublk_dbg(UBLK_DBG_DEV, "%s: daemon exit %d\b", ret);
+
+fail:
+       if (ret < 0)
+               ublk_send_dev_event(ctx, -1);
+       ublk_ctrl_deinit(dev);
+       return ret;
+}
+
+static int __cmd_dev_list(struct dev_ctx *ctx);
+
+static int cmd_dev_add(struct dev_ctx *ctx)
+{
+       int res;
+
+       ctx->_evtfd = eventfd(0, 0);
+       if (ctx->_evtfd < 0) {
+               ublk_err("%s: failed to create eventfd %s\n", __func__, strerror(errno));
+               exit(-1);
+       }
+
+       setsid();
+       res = fork();
+       if (res == 0) {
+               __cmd_dev_add(ctx);
+               exit(EXIT_SUCCESS);
+       } else if (res > 0) {
+               uint64_t id;
+
+               res = read(ctx->_evtfd, &id, sizeof(id));
+               close(ctx->_evtfd);
+               if (res == sizeof(id) && id != ERROR_EVTFD_DEVID) {
+                       ctx->dev_id = id - 1;
+                       return __cmd_dev_list(ctx);
+               }
+               exit(EXIT_FAILURE);
+       } else {
+               return res;
+       }
+}
+
+static int __cmd_dev_del(struct dev_ctx *ctx)
+{
+       int number = ctx->dev_id;
+       struct ublk_dev *dev;
+       int ret;
+
+       dev = ublk_ctrl_init();
+       dev->dev_info.dev_id = number;
+
+       ret = ublk_ctrl_get_info(dev);
+       if (ret < 0)
+               goto fail;
+
+       ret = ublk_ctrl_stop_dev(dev);
+       if (ret < 0)
+               ublk_err("%s: stop dev %d failed ret %d\n", __func__, number, ret);
+
+       ret = ublk_stop_io_daemon(dev);
+       if (ret < 0)
+               ublk_err("%s: stop daemon id %d dev %d, ret %d\n",
+                               __func__, dev->dev_info.ublksrv_pid, number, ret);
+       ublk_ctrl_del_dev(dev);
+fail:
+       if (ret >= 0)
+               ret = ublk_ctrl_get_info(dev);
+       ublk_ctrl_deinit(dev);
+
+       return (ret >= 0) ? 0 : ret;
+}
+
+static int cmd_dev_del(struct dev_ctx *ctx)
+{
+       int i;
+
+       if (ctx->dev_id >= 0 || !ctx->all)
+               return __cmd_dev_del(ctx);
+
+       for (i = 0; i < 255; i++) {
+               ctx->dev_id = i;
+               __cmd_dev_del(ctx);
+       }
+       return 0;
+}
+
+static int __cmd_dev_list(struct dev_ctx *ctx)
+{
+       struct ublk_dev *dev = ublk_ctrl_init();
+       int ret;
+
+       if (!dev)
+               return -ENODEV;
+
+       dev->dev_info.dev_id = ctx->dev_id;
+
+       ret = ublk_ctrl_get_info(dev);
+       if (ret < 0) {
+               if (ctx->logging)
+                       ublk_err("%s: can't get dev info from %d: %d\n",
+                                       __func__, ctx->dev_id, ret);
+       } else {
+               ublk_ctrl_dump(dev);
+       }
+
+       ublk_ctrl_deinit(dev);
+
+       return ret;
+}
+
+static int cmd_dev_list(struct dev_ctx *ctx)
+{
+       int i;
+
+       if (ctx->dev_id >= 0 || !ctx->all)
+               return __cmd_dev_list(ctx);
+
+       ctx->logging = false;
+       for (i = 0; i < 255; i++) {
+               ctx->dev_id = i;
+               __cmd_dev_list(ctx);
+       }
+       return 0;
+}
+
+static int cmd_dev_get_features(void)
+{
+#define const_ilog2(x) (63 - __builtin_clzll(x))
+       static const char *feat_map[] = {
+               [const_ilog2(UBLK_F_SUPPORT_ZERO_COPY)] = "ZERO_COPY",
+               [const_ilog2(UBLK_F_URING_CMD_COMP_IN_TASK)] = "COMP_IN_TASK",
+               [const_ilog2(UBLK_F_NEED_GET_DATA)] = "GET_DATA",
+               [const_ilog2(UBLK_F_USER_RECOVERY)] = "USER_RECOVERY",
+               [const_ilog2(UBLK_F_USER_RECOVERY_REISSUE)] = "RECOVERY_REISSUE",
+               [const_ilog2(UBLK_F_UNPRIVILEGED_DEV)] = "UNPRIVILEGED_DEV",
+               [const_ilog2(UBLK_F_CMD_IOCTL_ENCODE)] = "CMD_IOCTL_ENCODE",
+               [const_ilog2(UBLK_F_USER_COPY)] = "USER_COPY",
+               [const_ilog2(UBLK_F_ZONED)] = "ZONED",
+               [const_ilog2(UBLK_F_USER_RECOVERY_FAIL_IO)] = "RECOVERY_FAIL_IO",
+       };
+       struct ublk_dev *dev;
+       __u64 features = 0;
+       int ret;
+
+       dev = ublk_ctrl_init();
+       if (!dev) {
+               fprintf(stderr, "ublksrv_ctrl_init failed id\n");
+               return -EOPNOTSUPP;
+       }
+
+       ret = ublk_ctrl_get_features(dev, &features);
+       if (!ret) {
+               int i;
+
+               printf("ublk_drv features: 0x%llx\n", features);
+
+               for (i = 0; i < sizeof(features) * 8; i++) {
+                       const char *feat;
+
+                       if (!((1ULL << i)  & features))
+                               continue;
+                       if (i < sizeof(feat_map) / sizeof(feat_map[0]))
+                               feat = feat_map[i];
+                       else
+                               feat = "unknown";
+                       printf("\t%-20s: 0x%llx\n", feat, 1ULL << i);
+               }
+       }
+
+       return ret;
+}
+
+static int cmd_dev_help(char *exe)
+{
+       printf("%s add -t [null] [-q nr_queues] [-d depth] [-n dev_id]\n", exe);
+       printf("\t default: nr_queues=2(max 4), depth=128(max 128), dev_id=-1(auto allocation)\n");
+       printf("%s del [-n dev_id] -a \n", exe);
+       printf("\t -a delete all devices -n delete specified device\n");
+       printf("%s list [-n dev_id] -a \n", exe);
+       printf("\t -a list all devices, -n list specified device, default -a \n");
+       printf("%s features\n", exe);
+       return 0;
+}
+
+int main(int argc, char *argv[])
+{
+       static const struct option longopts[] = {
+               { "all",                0,      NULL, 'a' },
+               { "type",               1,      NULL, 't' },
+               { "number",             1,      NULL, 'n' },
+               { "queues",             1,      NULL, 'q' },
+               { "depth",              1,      NULL, 'd' },
+               { "debug_mask",         1,      NULL,  0  },
+               { "quiet",              0,      NULL,  0  },
+               { 0, 0, 0, 0 }
+       };
+       int option_idx, opt;
+       const char *cmd = argv[1];
+       struct dev_ctx ctx = {
+               .queue_depth    =       128,
+               .nr_hw_queues   =       2,
+               .dev_id         =       -1,
+               .tgt_type       =       "unknown",
+       };
+       int ret = -EINVAL, i;
+
+       if (argc == 1)
+               return ret;
+
+       optind = 2;
+       while ((opt = getopt_long(argc, argv, "t:n:d:q:a",
+                                 longopts, &option_idx)) != -1) {
+               switch (opt) {
+               case 'a':
+                       ctx.all = 1;
+                       break;
+               case 'n':
+                       ctx.dev_id = strtol(optarg, NULL, 10);
+                       break;
+               case 't':
+                       if (strlen(optarg) < sizeof(ctx.tgt_type))
+                               strcpy(ctx.tgt_type, optarg);
+                       break;
+               case 'q':
+                       ctx.nr_hw_queues = strtol(optarg, NULL, 10);
+                       break;
+               case 'd':
+                       ctx.queue_depth = strtol(optarg, NULL, 10);
+                       break;
+               case 0:
+                       if (!strcmp(longopts[option_idx].name, "debug_mask"))
+                               ublk_dbg_mask = strtol(optarg, NULL, 16);
+                       if (!strcmp(longopts[option_idx].name, "quiet"))
+                               ublk_dbg_mask = 0;
+                       break;
+               }
+       }
+
+       i = optind;
+       while (i < argc && ctx.nr_files < MAX_BACK_FILES) {
+               ctx.files[ctx.nr_files++] = argv[i++];
+       }
+
+       if (!strcmp(cmd, "add"))
+               ret = cmd_dev_add(&ctx);
+       else if (!strcmp(cmd, "del"))
+               ret = cmd_dev_del(&ctx);
+       else if (!strcmp(cmd, "list")) {
+               ctx.all = 1;
+               ret = cmd_dev_list(&ctx);
+       } else if (!strcmp(cmd, "help"))
+               ret = cmd_dev_help(argv[0]);
+       else if (!strcmp(cmd, "features"))
+               ret = cmd_dev_get_features();
+       else
+               cmd_dev_help(argv[0]);
+
+       return ret;
+}
diff --git a/tools/testing/selftests/ublk/kublk.h b/tools/testing/selftests/ublk/kublk.h
new file mode 100644 (file)
index 0000000..cb2540c
--- /dev/null
@@ -0,0 +1,252 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef KUBLK_INTERNAL_H
+#define KUBLK_INTERNAL_H
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <string.h>
+#include <pthread.h>
+#include <getopt.h>
+#include <limits.h>
+#include <poll.h>
+#include <sys/syscall.h>
+#include <sys/mman.h>
+#include <sys/ioctl.h>
+#include <sys/inotify.h>
+#include <sys/wait.h>
+#include <sys/eventfd.h>
+#include <liburing.h>
+#include <linux/ublk_cmd.h>
+
+#define __maybe_unused __attribute__((unused))
+#define MAX_BACK_FILES   4
+#ifndef min
+#define min(a, b) ((a) < (b) ? (a) : (b))
+#endif
+
+/****************** part 1: libublk ********************/
+
+#define CTRL_DEV               "/dev/ublk-control"
+#define UBLKC_DEV              "/dev/ublkc"
+#define UBLKB_DEV              "/dev/ublkb"
+#define UBLK_CTRL_RING_DEPTH            32
+#define ERROR_EVTFD_DEVID      -2
+
+/* queue idle timeout */
+#define UBLKSRV_IO_IDLE_SECS           20
+
+#define UBLK_IO_MAX_BYTES               65536
+#define UBLK_MAX_QUEUES                 4
+#define UBLK_QUEUE_DEPTH                128
+
+#define UBLK_DBG_DEV            (1U << 0)
+#define UBLK_DBG_QUEUE          (1U << 1)
+#define UBLK_DBG_IO_CMD         (1U << 2)
+#define UBLK_DBG_IO             (1U << 3)
+#define UBLK_DBG_CTRL_CMD       (1U << 4)
+#define UBLK_LOG                (1U << 5)
+
+struct ublk_dev;
+struct ublk_queue;
+
+struct dev_ctx {
+       char tgt_type[16];
+       unsigned long flags;
+       unsigned nr_hw_queues;
+       unsigned queue_depth;
+       int dev_id;
+       int nr_files;
+       char *files[MAX_BACK_FILES];
+       unsigned int    logging:1;
+       unsigned int    all:1;
+
+       int _evtfd;
+};
+
+struct ublk_ctrl_cmd_data {
+       __u32 cmd_op;
+#define CTRL_CMD_HAS_DATA      1
+#define CTRL_CMD_HAS_BUF       2
+       __u32 flags;
+
+       __u64 data[2];
+       __u64 addr;
+       __u32 len;
+};
+
+struct ublk_io {
+       char *buf_addr;
+
+#define UBLKSRV_NEED_FETCH_RQ          (1UL << 0)
+#define UBLKSRV_NEED_COMMIT_RQ_COMP    (1UL << 1)
+#define UBLKSRV_IO_FREE                        (1UL << 2)
+       unsigned short flags;
+       unsigned short refs;            /* used by target code only */
+
+       int result;
+};
+
+struct ublk_tgt_ops {
+       const char *name;
+       int (*init_tgt)(struct ublk_dev *);
+       void (*deinit_tgt)(struct ublk_dev *);
+
+       int (*queue_io)(struct ublk_queue *, int tag);
+       void (*tgt_io_done)(struct ublk_queue *,
+                       int tag, const struct io_uring_cqe *);
+};
+
+struct ublk_tgt {
+       unsigned long dev_size;
+       unsigned int  sq_depth;
+       unsigned int  cq_depth;
+       const struct ublk_tgt_ops *ops;
+       struct ublk_params params;
+       char backing_file[1024 - 8 - sizeof(struct ublk_params)];
+};
+
+struct ublk_queue {
+       int q_id;
+       int q_depth;
+       unsigned int cmd_inflight;
+       unsigned int io_inflight;
+       struct ublk_dev *dev;
+       const struct ublk_tgt_ops *tgt_ops;
+       char *io_cmd_buf;
+       struct io_uring ring;
+       struct ublk_io ios[UBLK_QUEUE_DEPTH];
+#define UBLKSRV_QUEUE_STOPPING (1U << 0)
+#define UBLKSRV_QUEUE_IDLE     (1U << 1)
+#define UBLKSRV_NO_BUF         (1U << 2)
+       unsigned state;
+       pid_t tid;
+       pthread_t thread;
+};
+
+struct ublk_dev {
+       struct ublk_tgt tgt;
+       struct ublksrv_ctrl_dev_info  dev_info;
+       struct ublk_queue q[UBLK_MAX_QUEUES];
+
+       int fds[2];     /* fds[0] points to /dev/ublkcN */
+       int nr_fds;
+       int ctrl_fd;
+       struct io_uring ring;
+};
+
+#ifndef offsetof
+#define offsetof(TYPE, MEMBER)  ((size_t)&((TYPE *)0)->MEMBER)
+#endif
+
+#ifndef container_of
+#define container_of(ptr, type, member) ({                              \
+       unsigned long __mptr = (unsigned long)(ptr);                    \
+       ((type *)(__mptr - offsetof(type, member))); })
+#endif
+
+#define round_up(val, rnd) \
+       (((val) + ((rnd) - 1)) & ~((rnd) - 1))
+
+
+extern unsigned int ublk_dbg_mask;
+extern int ublk_queue_io_cmd(struct ublk_queue *q, struct ublk_io *io, unsigned tag);
+
+static inline int is_target_io(__u64 user_data)
+{
+       return (user_data & (1ULL << 63)) != 0;
+}
+
+static inline __u64 build_user_data(unsigned tag, unsigned op,
+               unsigned tgt_data, unsigned is_target_io)
+{
+       assert(!(tag >> 16) && !(op >> 8) && !(tgt_data >> 16));
+
+       return tag | (op << 16) | (tgt_data << 24) | (__u64)is_target_io << 63;
+}
+
+static inline unsigned int user_data_to_tag(__u64 user_data)
+{
+       return user_data & 0xffff;
+}
+
+static inline unsigned int user_data_to_op(__u64 user_data)
+{
+       return (user_data >> 16) & 0xff;
+}
+
+static inline void ublk_err(const char *fmt, ...)
+{
+       va_list ap;
+
+       va_start(ap, fmt);
+       vfprintf(stderr, fmt, ap);
+}
+
+static inline void ublk_log(const char *fmt, ...)
+{
+       if (ublk_dbg_mask & UBLK_LOG) {
+               va_list ap;
+
+               va_start(ap, fmt);
+               vfprintf(stdout, fmt, ap);
+       }
+}
+
+static inline void ublk_dbg(int level, const char *fmt, ...)
+{
+       if (level & ublk_dbg_mask) {
+               va_list ap;
+
+               va_start(ap, fmt);
+               vfprintf(stdout, fmt, ap);
+       }
+}
+
+static inline struct io_uring_sqe *ublk_queue_alloc_sqe(struct ublk_queue *q)
+{
+       unsigned left = io_uring_sq_space_left(&q->ring);
+
+       if (left < 1)
+               io_uring_submit(&q->ring);
+       return io_uring_get_sqe(&q->ring);
+}
+
+static inline void *ublk_get_sqe_cmd(const struct io_uring_sqe *sqe)
+{
+       return (void *)&sqe->cmd;
+}
+
+static inline void ublk_mark_io_done(struct ublk_io *io, int res)
+{
+       io->flags |= (UBLKSRV_NEED_COMMIT_RQ_COMP | UBLKSRV_IO_FREE);
+       io->result = res;
+}
+
+static inline const struct ublksrv_io_desc *ublk_get_iod(const struct ublk_queue *q, int tag)
+{
+       return (struct ublksrv_io_desc *)&(q->io_cmd_buf[tag * sizeof(struct ublksrv_io_desc)]);
+}
+
+static inline void ublk_set_sqe_cmd_op(struct io_uring_sqe *sqe, __u32 cmd_op)
+{
+       __u32 *addr = (__u32 *)&sqe->off;
+
+       addr[0] = cmd_op;
+       addr[1] = 0;
+}
+
+static inline int ublk_complete_io(struct ublk_queue *q, unsigned tag, int res)
+{
+       struct ublk_io *io = &q->ios[tag];
+
+       ublk_mark_io_done(io, res);
+
+       return ublk_queue_io_cmd(q, io, tag);
+}
+
+extern const struct ublk_tgt_ops null_tgt_ops;
+
+#endif
diff --git a/tools/testing/selftests/ublk/null.c b/tools/testing/selftests/ublk/null.c
new file mode 100644 (file)
index 0000000..b6ef16a
--- /dev/null
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include "kublk.h"
+
+static int ublk_null_tgt_init(struct ublk_dev *dev)
+{
+       const struct ublksrv_ctrl_dev_info *info = &dev->dev_info;
+       unsigned long dev_size = 250UL << 30;
+
+       dev->tgt.dev_size = dev_size;
+       dev->tgt.params = (struct ublk_params) {
+               .types = UBLK_PARAM_TYPE_BASIC,
+               .basic = {
+                       .logical_bs_shift       = 9,
+                       .physical_bs_shift      = 12,
+                       .io_opt_shift           = 12,
+                       .io_min_shift           = 9,
+                       .max_sectors            = info->max_io_buf_bytes >> 9,
+                       .dev_sectors            = dev_size >> 9,
+               },
+       };
+
+       return 0;
+}
+
+static int ublk_null_queue_io(struct ublk_queue *q, int tag)
+{
+       const struct ublksrv_io_desc *iod = ublk_get_iod(q, tag);
+
+       ublk_complete_io(q, tag, iod->nr_sectors << 9);
+       return 0;
+}
+
+const struct ublk_tgt_ops null_tgt_ops = {
+       .name = "null",
+       .init_tgt = ublk_null_tgt_init,
+       .queue_io = ublk_null_queue_io,
+};
diff --git a/tools/testing/selftests/ublk/test_common.sh b/tools/testing/selftests/ublk/test_common.sh
new file mode 100755 (executable)
index 0000000..ffcdfdc
--- /dev/null
@@ -0,0 +1,58 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+_check_root() {
+       local ksft_skip=4
+
+       if [ $UID != 0 ]; then
+               echo please run this as root >&2
+               exit $ksft_skip
+       fi
+}
+
+_remove_ublk_devices() {
+       ${UBLK_PROG} del -a
+}
+
+_get_ublk_dev_state() {
+       ${UBLK_PROG} list -n "$1" | grep "state" | awk '{print $11}'
+}
+
+_get_ublk_daemon_pid() {
+       ${UBLK_PROG} list -n "$1" | grep "pid" | awk '{print $7}'
+}
+
+_prep_test() {
+       _check_root
+       local type=$1
+       shift 1
+       echo "ublk $type: $@"
+}
+
+_show_result()
+{
+       if [ $2 -ne 0 ]; then
+               echo "$1 : [FAIL]"
+       else
+               echo "$1 : [PASS]"
+       fi
+}
+
+_cleanup_test() {
+       ${UBLK_PROG} del -n $1
+}
+
+_add_ublk_dev() {
+       local kublk_temp=`mktemp /tmp/kublk-XXXXXX`
+       ${UBLK_PROG} add $@ > ${kublk_temp} 2>&1
+       if [ $? -ne 0 ]; then
+               echo "fail to add ublk dev $@"
+               exit -1
+       fi
+       local dev_id=`grep "dev id" ${kublk_temp} | awk -F '[ :]' '{print $3}'`
+       udevadm settle
+       rm -f ${kublk_temp}
+       echo ${dev_id}
+}
+
+export UBLK_PROG=$(pwd)/kublk
diff --git a/tools/testing/selftests/ublk/test_null_01.sh b/tools/testing/selftests/ublk/test_null_01.sh
new file mode 100755 (executable)
index 0000000..04fc3ac
--- /dev/null
@@ -0,0 +1,19 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+. test_common.sh
+
+TID="null_01"
+ERR_CODE=0
+
+_prep_test "null" "basic IO test"
+
+dev_id=`_add_ublk_dev -t null`
+
+# run fio over the two disks
+fio --name=job1 --filename=/dev/ublkb${dev_id} --ioengine=libaio --rw=readwrite --iodepth=32 --size=256M > /dev/null 2>&1
+ERR_CODE=$?
+
+_cleanup_test ${dev_id} "null"
+
+_show_result $TID $ERR_CODE