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author | Ming Lei <ming.lei@redhat.com> | 2023-10-09 11:33:18 +0200 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2023-10-17 16:27:55 +0200 |
commit | 85248d670b71d9edda9459ee14fdc85c8e9632c0 (patch) | |
tree | 81daebf9d7990c8ebc0827b09496d35bd99e96e1 /drivers/block | |
parent | ublk: make sure io cmd handled in submitter task context (diff) | |
download | linux-85248d670b71d9edda9459ee14fdc85c8e9632c0.tar.xz linux-85248d670b71d9edda9459ee14fdc85c8e9632c0.zip |
ublk: move ublk_cancel_dev() out of ub->mutex
ublk_cancel_dev() just calls ublk_cancel_queue() to cancel all pending
io commands after ublk request queue is idle. The only protection is just
the read & write of ubq->nr_io_ready and avoid duplicated command cancel,
so add one per-queue lock with cancel flag for providing this protection,
meantime move ublk_cancel_dev() out of ub->mutex.
Then we needn't to call io_uring_cmd_complete_in_task() to cancel
pending command. And the same cancel logic will be re-used for
cancelable uring command.
This patch basically reverts commit ac5902f84bb5 ("ublk: fix AB-BA lockdep warning").
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20231009093324.957829-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/block')
-rw-r--r-- | drivers/block/ublk_drv.c | 40 |
1 files changed, 23 insertions, 17 deletions
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 2e2efae62c77..5b1cf94bd22f 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -115,6 +115,9 @@ struct ublk_uring_cmd_pdu { */ #define UBLK_IO_FLAG_NEED_GET_DATA 0x08 +/* atomic RW with ubq->cancel_lock */ +#define UBLK_IO_FLAG_CANCELED 0x80000000 + struct ublk_io { /* userspace buffer address from io cmd */ __u64 addr; @@ -139,6 +142,7 @@ struct ublk_queue { bool force_abort; bool timeout; unsigned short nr_io_ready; /* how many ios setup */ + spinlock_t cancel_lock; struct ublk_device *dev; struct ublk_io ios[]; }; @@ -1474,28 +1478,28 @@ static inline bool ublk_queue_ready(struct ublk_queue *ubq) return ubq->nr_io_ready == ubq->q_depth; } -static void ublk_cmd_cancel_cb(struct io_uring_cmd *cmd, unsigned issue_flags) -{ - io_uring_cmd_done(cmd, UBLK_IO_RES_ABORT, 0, issue_flags); -} - static void ublk_cancel_queue(struct ublk_queue *ubq) { int i; - if (!ublk_queue_ready(ubq)) - return; - for (i = 0; i < ubq->q_depth; i++) { struct ublk_io *io = &ubq->ios[i]; - if (io->flags & UBLK_IO_FLAG_ACTIVE) - io_uring_cmd_complete_in_task(io->cmd, - ublk_cmd_cancel_cb); - } + if (io->flags & UBLK_IO_FLAG_ACTIVE) { + bool done; - /* all io commands are canceled */ - ubq->nr_io_ready = 0; + spin_lock(&ubq->cancel_lock); + done = !!(io->flags & UBLK_IO_FLAG_CANCELED); + if (!done) + io->flags |= UBLK_IO_FLAG_CANCELED; + spin_unlock(&ubq->cancel_lock); + + if (!done) + io_uring_cmd_done(io->cmd, + UBLK_IO_RES_ABORT, 0, + IO_URING_F_UNLOCKED); + } + } } /* Cancel all pending commands, must be called after del_gendisk() returns */ @@ -1542,7 +1546,6 @@ static void __ublk_quiesce_dev(struct ublk_device *ub) blk_mq_quiesce_queue(ub->ub_disk->queue); ublk_wait_tagset_rqs_idle(ub); ub->dev_info.state = UBLK_S_DEV_QUIESCED; - ublk_cancel_dev(ub); /* we are going to release task_struct of ubq_daemon and resets * ->ubq_daemon to NULL. So in monitor_work, check on ubq_daemon causes UAF. * Besides, monitor_work is not necessary in QUIESCED state since we have @@ -1565,6 +1568,7 @@ static void ublk_quiesce_work_fn(struct work_struct *work) __ublk_quiesce_dev(ub); unlock: mutex_unlock(&ub->mutex); + ublk_cancel_dev(ub); } static void ublk_unquiesce_dev(struct ublk_device *ub) @@ -1604,8 +1608,8 @@ static void ublk_stop_dev(struct ublk_device *ub) put_disk(ub->ub_disk); ub->ub_disk = NULL; unlock: - ublk_cancel_dev(ub); mutex_unlock(&ub->mutex); + ublk_cancel_dev(ub); cancel_delayed_work_sync(&ub->monitor_work); } @@ -1979,6 +1983,7 @@ static int ublk_init_queue(struct ublk_device *ub, int q_id) void *ptr; int size; + spin_lock_init(&ubq->cancel_lock); ubq->flags = ub->dev_info.flags; ubq->q_id = q_id; ubq->q_depth = ub->dev_info.queue_depth; @@ -2593,8 +2598,9 @@ static void ublk_queue_reinit(struct ublk_device *ub, struct ublk_queue *ubq) int i; WARN_ON_ONCE(!(ubq->ubq_daemon && ubq_daemon_is_dying(ubq))); + /* All old ioucmds have to be completed */ - WARN_ON_ONCE(ubq->nr_io_ready); + ubq->nr_io_ready = 0; /* old daemon is PF_EXITING, put it now */ put_task_struct(ubq->ubq_daemon); /* We have to reset it to NULL, otherwise ub won't accept new FETCH_REQ */ |