[PATCH v2 04/14] ublk: handle UBLK_IO_FETCH_REQ earlier
From: Caleb Sander Mateos <hidden>
Date: 2025-06-20 15:10:16
Subsystem:
block layer, the rest, ublk userspace block driver · Maintainers:
Jens Axboe, Linus Torvalds, Ming Lei
Check for UBLK_IO_FETCH_REQ early in __ublk_ch_uring_cmd() and skip the rest of the checks in this case. This allows removing the checks for NULL io->task and UBLK_IO_FLAG_OWNED_BY_SRV unset in io->flags, which are only allowed for FETCH. Signed-off-by: Caleb Sander Mateos <redacted> Reviewed-by: Ming Lei <redacted> --- drivers/block/ublk_drv.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-)
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index aea2e9200311..8df70a5fb129 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c@@ -2197,23 +2197,31 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd, if (tag >= ubq->q_depth) goto out; io = &ubq->ios[tag]; + /* UBLK_IO_FETCH_REQ can be handled on any task, which sets io->task */ + if (unlikely(_IOC_NR(cmd_op) == UBLK_IO_FETCH_REQ)) { + ret = ublk_fetch(cmd, ubq, io, ub_cmd->addr); + if (ret) + goto out; + + ublk_prep_cancel(cmd, issue_flags, ubq, tag); + return -EIOCBQUEUED; + } + task = READ_ONCE(io->task); - if (task && task != current) + if (task != current) goto out; /* there is pending io cmd, something must be wrong */ if (io->flags & UBLK_IO_FLAG_ACTIVE) { ret = -EBUSY; goto out; } - /* only UBLK_IO_FETCH_REQ is allowed if io is not OWNED_BY_SRV */ - if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV) && - _IOC_NR(cmd_op) != UBLK_IO_FETCH_REQ) + if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV)) goto out; /* * ensure that the user issues UBLK_IO_NEED_GET_DATA * iff the driver have set the UBLK_IO_FLAG_NEED_GET_DATA.
@@ -2225,15 +2233,10 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd, switch (_IOC_NR(cmd_op)) { case UBLK_IO_REGISTER_IO_BUF: return ublk_register_io_buf(cmd, ubq, io, ub_cmd->addr, issue_flags); case UBLK_IO_UNREGISTER_IO_BUF: return ublk_unregister_io_buf(cmd, ubq, ub_cmd->addr, issue_flags); - case UBLK_IO_FETCH_REQ: - ret = ublk_fetch(cmd, ubq, io, ub_cmd->addr); - if (ret) - goto out; - break; case UBLK_IO_COMMIT_AND_FETCH_REQ: ret = ublk_commit_and_fetch(ubq, io, cmd, ub_cmd, issue_flags); if (ret) goto out; break;
--
2.45.2