From 776617db78c6d208780e7c69d4d68d1fa82913de Mon Sep 17 00:00:00 2001 From: Tobias Holl Date: Wed, 3 May 2023 08:59:50 -0600 Subject: [PATCH 1/4] io_uring/rsrc: check for nonconsecutive pages Pages that are from the same folio do not necessarily need to be consecutive. In that case, we cannot consolidate them into a single bvec entry. Before applying the huge page optimization from commit 57bebf807e2a ("io_uring/rsrc: optimise registered huge pages"), check that the memory is actually consecutive. Cc: stable@vger.kernel.org Fixes: 57bebf807e2a ("io_uring/rsrc: optimise registered huge pages") Signed-off-by: Tobias Holl [axboe: formatting] Signed-off-by: Jens Axboe --- io_uring/rsrc.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c index ddee7adb4006..00affcf811ad 100644 --- a/io_uring/rsrc.c +++ b/io_uring/rsrc.c @@ -1117,7 +1117,12 @@ static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, if (nr_pages > 1) { folio = page_folio(pages[0]); for (i = 1; i < nr_pages; i++) { - if (page_folio(pages[i]) != folio) { + /* + * Pages must be consecutive and on the same folio for + * this to work + */ + if (page_folio(pages[i]) != folio || + pages[i] != pages[i - 1] + 1) { folio = NULL; break; } From 96c7d4f81db0fea05c0792f7563ae0cb4ad5f022 Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Thu, 4 May 2023 05:18:54 -0700 Subject: [PATCH 2/4] io_uring: Create a helper to return the SQE size Create a simple helper that returns the size of the SQE. The SQE could have two size, depending of the flags. If IO_URING_SETUP_SQE128 flag is set, then return a double SQE, otherwise returns the sizeof of io_uring_sqe (64 bytes). Signed-off-by: Breno Leitao Reviewed-by: Christoph Hellwig Reviewed-by: Pavel Begunkov Link: https://lore.kernel.org/r/20230504121856.904491-2-leitao@debian.org Signed-off-by: Jens Axboe --- io_uring/io_uring.h | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h index 25515d69d205..259bf798a390 100644 --- a/io_uring/io_uring.h +++ b/io_uring/io_uring.h @@ -394,4 +394,14 @@ static inline void io_req_queue_tw_complete(struct io_kiocb *req, s32 res) io_req_task_work_add(req); } +/* + * IORING_SETUP_SQE128 contexts allocate twice the normal SQE size for each + * slot. + */ +static inline size_t uring_sqe_size(struct io_ring_ctx *ctx) +{ + if (ctx->flags & IORING_SETUP_SQE128) + return 2 * sizeof(struct io_uring_sqe); + return sizeof(struct io_uring_sqe); +} #endif From fd9b8547bc5c34186dc42ea05fb4380d21695374 Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Thu, 4 May 2023 05:18:55 -0700 Subject: [PATCH 3/4] io_uring: Pass whole sqe to commands Currently uring CMD operation relies on having large SQEs, but future operations might want to use normal SQE. The io_uring_cmd currently only saves the payload (cmd) part of the SQE, but, for commands that use normal SQE size, it might be necessary to access the initial SQE fields outside of the payload/cmd block. So, saves the whole SQE other than just the pdu. This changes slightly how the io_uring_cmd works, since the cmd structures and callbacks are not opaque to io_uring anymore. I.e, the callbacks can look at the SQE entries, not only, in the cmd structure. The main advantage is that we don't need to create custom structures for simple commands. Creates io_uring_sqe_cmd() that returns the cmd private data as a null pointer and avoids casting in the callee side. Also, make most of ublk_drv's sqe->cmd priv structure into const, and use io_uring_sqe_cmd() to get the private structure, removing the unwanted cast. (There is one case where the cast is still needed since the header->{len,addr} is updated in the private structure) Suggested-by: Pavel Begunkov Signed-off-by: Breno Leitao Reviewed-by: Keith Busch Reviewed-by: Christoph Hellwig Reviewed-by: Pavel Begunkov Link: https://lore.kernel.org/r/20230504121856.904491-3-leitao@debian.org Signed-off-by: Jens Axboe --- drivers/block/ublk_drv.c | 26 +++++++++++++------------- drivers/nvme/host/ioctl.c | 2 +- include/linux/io_uring.h | 7 ++++++- io_uring/opdef.c | 2 +- io_uring/uring_cmd.c | 9 +++------ 5 files changed, 24 insertions(+), 22 deletions(-) diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index c73cc57ec547..42f4d7ca962e 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -1019,7 +1019,7 @@ static int ublk_ch_mmap(struct file *filp, struct vm_area_struct *vma) } static void ublk_commit_completion(struct ublk_device *ub, - struct ublksrv_io_cmd *ub_cmd) + const struct ublksrv_io_cmd *ub_cmd) { u32 qid = ub_cmd->q_id, tag = ub_cmd->tag; struct ublk_queue *ubq = ublk_get_queue(ub, qid); @@ -1263,7 +1263,7 @@ static void ublk_handle_need_get_data(struct ublk_device *ub, int q_id, static int ublk_ch_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) { - struct ublksrv_io_cmd *ub_cmd = (struct ublksrv_io_cmd *)cmd->cmd; + const struct ublksrv_io_cmd *ub_cmd = io_uring_sqe_cmd(cmd->sqe); struct ublk_device *ub = cmd->file->private_data; struct ublk_queue *ubq; struct ublk_io *io; @@ -1567,7 +1567,7 @@ static struct ublk_device *ublk_get_device_from_id(int idx) static int ublk_ctrl_start_dev(struct ublk_device *ub, struct io_uring_cmd *cmd) { - struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); int ublksrv_pid = (int)header->data[0]; struct gendisk *disk; int ret = -EINVAL; @@ -1630,7 +1630,7 @@ out_unlock: static int ublk_ctrl_get_queue_affinity(struct ublk_device *ub, struct io_uring_cmd *cmd) { - struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); void __user *argp = (void __user *)(unsigned long)header->addr; cpumask_var_t cpumask; unsigned long queue; @@ -1681,7 +1681,7 @@ static inline void ublk_dump_dev_info(struct ublksrv_ctrl_dev_info *info) static int ublk_ctrl_add_dev(struct io_uring_cmd *cmd) { - struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); void __user *argp = (void __user *)(unsigned long)header->addr; struct ublksrv_ctrl_dev_info info; struct ublk_device *ub; @@ -1844,7 +1844,7 @@ static int ublk_ctrl_del_dev(struct ublk_device **p_ub) static inline void ublk_ctrl_cmd_dump(struct io_uring_cmd *cmd) { - struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); pr_devel("%s: cmd_op %x, dev id %d qid %d data %llx buf %llx len %u\n", __func__, cmd->cmd_op, header->dev_id, header->queue_id, @@ -1863,7 +1863,7 @@ static int ublk_ctrl_stop_dev(struct ublk_device *ub) static int ublk_ctrl_get_dev_info(struct ublk_device *ub, struct io_uring_cmd *cmd) { - struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); void __user *argp = (void __user *)(unsigned long)header->addr; if (header->len < sizeof(struct ublksrv_ctrl_dev_info) || !header->addr) @@ -1894,7 +1894,7 @@ static void ublk_ctrl_fill_params_devt(struct ublk_device *ub) static int ublk_ctrl_get_params(struct ublk_device *ub, struct io_uring_cmd *cmd) { - struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); void __user *argp = (void __user *)(unsigned long)header->addr; struct ublk_params_header ph; int ret; @@ -1925,7 +1925,7 @@ static int ublk_ctrl_get_params(struct ublk_device *ub, static int ublk_ctrl_set_params(struct ublk_device *ub, struct io_uring_cmd *cmd) { - struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); void __user *argp = (void __user *)(unsigned long)header->addr; struct ublk_params_header ph; int ret = -EFAULT; @@ -1983,7 +1983,7 @@ static void ublk_queue_reinit(struct ublk_device *ub, struct ublk_queue *ubq) static int ublk_ctrl_start_recovery(struct ublk_device *ub, struct io_uring_cmd *cmd) { - struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); int ret = -EINVAL; int i; @@ -2025,7 +2025,7 @@ static int ublk_ctrl_start_recovery(struct ublk_device *ub, static int ublk_ctrl_end_recovery(struct ublk_device *ub, struct io_uring_cmd *cmd) { - struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); int ublksrv_pid = (int)header->data[0]; int ret = -EINVAL; @@ -2092,7 +2092,7 @@ exit: static int ublk_ctrl_uring_cmd_permission(struct ublk_device *ub, struct io_uring_cmd *cmd) { - struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)io_uring_sqe_cmd(cmd->sqe); bool unprivileged = ub->dev_info.flags & UBLK_F_UNPRIVILEGED_DEV; void __user *argp = (void __user *)(unsigned long)header->addr; char *dev_path = NULL; @@ -2171,7 +2171,7 @@ exit: static int ublk_ctrl_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) { - struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); struct ublk_device *ub = NULL; int ret = -EINVAL; diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c index d24ea2e05156..81c5c9e38477 100644 --- a/drivers/nvme/host/ioctl.c +++ b/drivers/nvme/host/ioctl.c @@ -552,7 +552,7 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns, struct io_uring_cmd *ioucmd, unsigned int issue_flags, bool vec) { struct nvme_uring_cmd_pdu *pdu = nvme_uring_cmd_pdu(ioucmd); - const struct nvme_uring_cmd *cmd = ioucmd->cmd; + const struct nvme_uring_cmd *cmd = io_uring_sqe_cmd(ioucmd->sqe); struct request_queue *q = ns ? ns->queue : ctrl->admin_q; struct nvme_uring_data d; struct nvme_command c; diff --git a/include/linux/io_uring.h b/include/linux/io_uring.h index 35b9328ca335..3399d979ee1c 100644 --- a/include/linux/io_uring.h +++ b/include/linux/io_uring.h @@ -24,7 +24,7 @@ enum io_uring_cmd_flags { struct io_uring_cmd { struct file *file; - const void *cmd; + const struct io_uring_sqe *sqe; union { /* callback to defer completions to task context */ void (*task_work_cb)(struct io_uring_cmd *cmd, unsigned); @@ -66,6 +66,11 @@ static inline void io_uring_free(struct task_struct *tsk) if (tsk->io_uring) __io_uring_free(tsk); } + +static inline const void *io_uring_sqe_cmd(const struct io_uring_sqe *sqe) +{ + return sqe->cmd; +} #else static inline int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw, struct iov_iter *iter, void *ioucmd) diff --git a/io_uring/opdef.c b/io_uring/opdef.c index cca7c5b55208..3b9c6489b8b6 100644 --- a/io_uring/opdef.c +++ b/io_uring/opdef.c @@ -627,7 +627,7 @@ const struct io_cold_def io_cold_defs[] = { }, [IORING_OP_URING_CMD] = { .name = "URING_CMD", - .async_size = uring_cmd_pdu_size(1), + .async_size = 2 * sizeof(struct io_uring_sqe), .prep_async = io_uring_cmd_prep_async, }, [IORING_OP_SEND_ZC] = { diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c index 5113c9a48583..ed536d7499db 100644 --- a/io_uring/uring_cmd.c +++ b/io_uring/uring_cmd.c @@ -69,15 +69,12 @@ EXPORT_SYMBOL_GPL(io_uring_cmd_done); int io_uring_cmd_prep_async(struct io_kiocb *req) { struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); - size_t cmd_size; BUILD_BUG_ON(uring_cmd_pdu_size(0) != 16); BUILD_BUG_ON(uring_cmd_pdu_size(1) != 80); - cmd_size = uring_cmd_pdu_size(req->ctx->flags & IORING_SETUP_SQE128); - - memcpy(req->async_data, ioucmd->cmd, cmd_size); - ioucmd->cmd = req->async_data; + memcpy(req->async_data, ioucmd->sqe, uring_sqe_size(req->ctx)); + ioucmd->sqe = req->async_data; return 0; } @@ -103,7 +100,7 @@ int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) req->imu = ctx->user_bufs[index]; io_req_set_rsrc_node(req, ctx, 0); } - ioucmd->cmd = sqe->cmd; + ioucmd->sqe = sqe; ioucmd->cmd_op = READ_ONCE(sqe->cmd_op); return 0; } From d2b7fa6174bc4260e496cbf84375c73636914641 Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Thu, 4 May 2023 05:18:56 -0700 Subject: [PATCH 4/4] io_uring: Remove unnecessary BUILD_BUG_ON In the io_uring_cmd_prep_async() there is an unnecessary compilation time check to check if cmd is correctly placed at field 48 of the SQE. This is unnecessary, since this check is already in place at io_uring_init(): BUILD_BUG_SQE_ELEM(48, __u64, addr3); Remove it and the uring_cmd_pdu_size() function, which is not used anymore. Keith started a discussion about this topic in the following thread: Link: https://lore.kernel.org/lkml/ZDBmQOhbyU0iLhMw@kbusch-mbp.dhcp.thefacebook.com/ Signed-off-by: Breno Leitao Reviewed-by: Christoph Hellwig Reviewed-by: Pavel Begunkov Link: https://lore.kernel.org/r/20230504121856.904491-4-leitao@debian.org Signed-off-by: Jens Axboe --- io_uring/uring_cmd.c | 3 --- io_uring/uring_cmd.h | 8 -------- 2 files changed, 11 deletions(-) diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c index ed536d7499db..5e32db48696d 100644 --- a/io_uring/uring_cmd.c +++ b/io_uring/uring_cmd.c @@ -70,9 +70,6 @@ int io_uring_cmd_prep_async(struct io_kiocb *req) { struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); - BUILD_BUG_ON(uring_cmd_pdu_size(0) != 16); - BUILD_BUG_ON(uring_cmd_pdu_size(1) != 80); - memcpy(req->async_data, ioucmd->sqe, uring_sqe_size(req->ctx)); ioucmd->sqe = req->async_data; return 0; diff --git a/io_uring/uring_cmd.h b/io_uring/uring_cmd.h index 7c6697d13cb2..8117684ec3ca 100644 --- a/io_uring/uring_cmd.h +++ b/io_uring/uring_cmd.h @@ -3,11 +3,3 @@ int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags); int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe); int io_uring_cmd_prep_async(struct io_kiocb *req); - -/* - * The URING_CMD payload starts at 'cmd' in the first sqe, and continues into - * the following sqe if SQE128 is used. - */ -#define uring_cmd_pdu_size(is_sqe128) \ - ((1 + !!(is_sqe128)) * sizeof(struct io_uring_sqe) - \ - offsetof(struct io_uring_sqe, cmd))