6.18-stable review patch. If anyone has any objections, please let me know.
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From: Ming Lei ming.lei@redhat.com
[ Upstream commit 0a9beafa7c633e6ff66b05b81eea78231b7e6520 ]
Refactor auto buffer register code and prepare for supporting batch IO feature, and the main motivation is to put 'ublk_io' operation code together, so that per-io lock can be applied for the code block.
The key changes are: - Rename ublk_auto_buf_reg() as ublk_do_auto_buf_reg() - Introduce an enum `auto_buf_reg_res` to represent the result of the buffer registration attempt (FAIL, FALLBACK, OK). - Split the existing `ublk_do_auto_buf_reg` function into two: - `__ublk_do_auto_buf_reg`: Performs the actual buffer registration and returns the `auto_buf_reg_res` status. - `ublk_do_auto_buf_reg`: A wrapper that calls the internal function and handles the I/O preparation based on the result. - Introduce `ublk_prep_auto_buf_reg_io` to encapsulate the logic for preparing the I/O for completion after buffer registration. - Pass the `tag` directly to `ublk_auto_buf_reg_fallback` to avoid recalculating it.
This refactoring makes the control flow clearer and isolates the different stages of the auto buffer registration process.
Reviewed-by: Caleb Sander Mateos csander@purestorage.com Signed-off-by: Ming Lei ming.lei@redhat.com Signed-off-by: Jens Axboe axboe@kernel.dk Stable-dep-of: c258f5c4502c ("ublk: fix deadlock when reading partition table") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/block/ublk_drv.c | 64 +++++++++++++++++++++++++++------------- 1 file changed, 43 insertions(+), 21 deletions(-)
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index c9d258b99090..bdb897d44089 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -1234,17 +1234,37 @@ static inline void __ublk_abort_rq(struct ublk_queue *ubq, }
static void -ublk_auto_buf_reg_fallback(const struct ublk_queue *ubq, struct ublk_io *io) +ublk_auto_buf_reg_fallback(const struct ublk_queue *ubq, unsigned tag) { - unsigned tag = io - ubq->ios; struct ublksrv_io_desc *iod = ublk_get_iod(ubq, tag);
iod->op_flags |= UBLK_IO_F_NEED_REG_BUF; }
-static bool ublk_auto_buf_reg(const struct ublk_queue *ubq, struct request *req, - struct ublk_io *io, struct io_uring_cmd *cmd, - unsigned int issue_flags) +enum auto_buf_reg_res { + AUTO_BUF_REG_FAIL, + AUTO_BUF_REG_FALLBACK, + AUTO_BUF_REG_OK, +}; + +static void ublk_prep_auto_buf_reg_io(const struct ublk_queue *ubq, + struct request *req, struct ublk_io *io, + struct io_uring_cmd *cmd, + enum auto_buf_reg_res res) +{ + if (res == AUTO_BUF_REG_OK) { + io->task_registered_buffers = 1; + io->buf_ctx_handle = io_uring_cmd_ctx_handle(cmd); + io->flags |= UBLK_IO_FLAG_AUTO_BUF_REG; + } + ublk_init_req_ref(ubq, io); + __ublk_prep_compl_io_cmd(io, req); +} + +static enum auto_buf_reg_res +__ublk_do_auto_buf_reg(const struct ublk_queue *ubq, struct request *req, + struct ublk_io *io, struct io_uring_cmd *cmd, + unsigned int issue_flags) { int ret;
@@ -1252,29 +1272,27 @@ static bool ublk_auto_buf_reg(const struct ublk_queue *ubq, struct request *req, io->buf.auto_reg.index, issue_flags); if (ret) { if (io->buf.auto_reg.flags & UBLK_AUTO_BUF_REG_FALLBACK) { - ublk_auto_buf_reg_fallback(ubq, io); - return true; + ublk_auto_buf_reg_fallback(ubq, req->tag); + return AUTO_BUF_REG_FALLBACK; } blk_mq_end_request(req, BLK_STS_IOERR); - return false; + return AUTO_BUF_REG_FAIL; }
- io->task_registered_buffers = 1; - io->buf_ctx_handle = io_uring_cmd_ctx_handle(cmd); - io->flags |= UBLK_IO_FLAG_AUTO_BUF_REG; - return true; + return AUTO_BUF_REG_OK; }
-static bool ublk_prep_auto_buf_reg(struct ublk_queue *ubq, - struct request *req, struct ublk_io *io, - struct io_uring_cmd *cmd, - unsigned int issue_flags) +static void ublk_do_auto_buf_reg(const struct ublk_queue *ubq, struct request *req, + struct ublk_io *io, struct io_uring_cmd *cmd, + unsigned int issue_flags) { - ublk_init_req_ref(ubq, io); - if (ublk_support_auto_buf_reg(ubq) && ublk_rq_has_data(req)) - return ublk_auto_buf_reg(ubq, req, io, cmd, issue_flags); + enum auto_buf_reg_res res = __ublk_do_auto_buf_reg(ubq, req, io, cmd, + issue_flags);
- return true; + if (res != AUTO_BUF_REG_FAIL) { + ublk_prep_auto_buf_reg_io(ubq, req, io, cmd, res); + io_uring_cmd_done(cmd, UBLK_IO_RES_OK, issue_flags); + } }
static bool ublk_start_io(const struct ublk_queue *ubq, struct request *req, @@ -1347,8 +1365,12 @@ static void ublk_dispatch_req(struct ublk_queue *ubq, if (!ublk_start_io(ubq, req, io)) return;
- if (ublk_prep_auto_buf_reg(ubq, req, io, io->cmd, issue_flags)) + if (ublk_support_auto_buf_reg(ubq) && ublk_rq_has_data(req)) { + ublk_do_auto_buf_reg(ubq, req, io, io->cmd, issue_flags); + } else { + ublk_init_req_ref(ubq, io); ublk_complete_io_cmd(io, req, UBLK_IO_RES_OK, issue_flags); + } }
static void ublk_cmd_tw_cb(struct io_uring_cmd *cmd,