From 4dde0cc4459cfc366b0227790eec122bce576990 Mon Sep 17 00:00:00 2001 From: Anuj Gupta Date: Thu, 28 Nov 2024 16:52:36 +0530 Subject: [PATCH] io_uring: introduce attributes for read/write and PI support Add the ability to pass additional attributes along with read/write. Application can prepare attibute specific information and pass its address using the SQE field: __u64 attr_ptr; Along with setting a mask indicating attributes being passed: __u64 attr_type_mask; Overall 64 attributes are allowed and currently one attribute 'IORING_RW_ATTR_FLAG_PI' is supported. With PI attribute, userspace can pass following information: - flags: integrity check flags IO_INTEGRITY_CHK_{GUARD/APPTAG/REFTAG} - len: length of PI/metadata buffer - addr: address of metadata buffer - seed: seed value for reftag remapping - app_tag: application defined 16b value Process this information to prepare uio_meta_descriptor and pass it down using kiocb->private. PI attribute is supported only for direct IO. Signed-off-by: Anuj Gupta Signed-off-by: Kanchan Joshi Link: https://lore.kernel.org/r/20241128112240.8867-7-anuj20.g@samsung.com Signed-off-by: Jens Axboe --- include/uapi/linux/io_uring.h | 16 +++++++ io_uring/io_uring.c | 2 + io_uring/rw.c | 83 ++++++++++++++++++++++++++++++++++- io_uring/rw.h | 14 +++++- 4 files changed, 112 insertions(+), 3 deletions(-) diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index aac9a4f8fa9a..38f0d6b10eaf 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -98,6 +98,10 @@ struct io_uring_sqe { __u64 addr3; __u64 __pad2[1]; }; + struct { + __u64 attr_ptr; /* pointer to attribute information */ + __u64 attr_type_mask; /* bit mask of attributes */ + }; __u64 optval; /* * If the ring is initialized with IORING_SETUP_SQE128, then @@ -107,6 +111,18 @@ struct io_uring_sqe { }; }; +/* sqe->attr_type_mask flags */ +#define IORING_RW_ATTR_FLAG_PI (1U << 0) +/* PI attribute information */ +struct io_uring_attr_pi { + __u16 flags; + __u16 app_tag; + __u32 len; + __u64 addr; + __u64 seed; + __u64 rsvd; +}; + /* * If sqe->file_index is set to this for opcodes that instantiate a new * direct descriptor (like openat/openat2/accept), then io_uring will allocate diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 849d8881d0b7..a8cbe674e5d6 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -3871,6 +3871,8 @@ static int __init io_uring_init(void) BUILD_BUG_SQE_ELEM(46, __u16, __pad3[0]); BUILD_BUG_SQE_ELEM(48, __u64, addr3); BUILD_BUG_SQE_ELEM_SIZE(48, 0, cmd); + BUILD_BUG_SQE_ELEM(48, __u64, attr_ptr); + BUILD_BUG_SQE_ELEM(56, __u64, attr_type_mask); BUILD_BUG_SQE_ELEM(56, __u64, __pad2); BUILD_BUG_ON(sizeof(struct io_uring_files_update) != diff --git a/io_uring/rw.c b/io_uring/rw.c index 0bcb83e4ce3c..04e4467ab0ee 100644 --- a/io_uring/rw.c +++ b/io_uring/rw.c @@ -257,11 +257,53 @@ static int io_prep_rw_setup(struct io_kiocb *req, int ddir, bool do_import) return 0; } +static inline void io_meta_save_state(struct io_async_rw *io) +{ + io->meta_state.seed = io->meta.seed; + iov_iter_save_state(&io->meta.iter, &io->meta_state.iter_meta); +} + +static inline void io_meta_restore(struct io_async_rw *io, struct kiocb *kiocb) +{ + if (kiocb->ki_flags & IOCB_HAS_METADATA) { + io->meta.seed = io->meta_state.seed; + iov_iter_restore(&io->meta.iter, &io->meta_state.iter_meta); + } +} + +static int io_prep_rw_pi(struct io_kiocb *req, struct io_rw *rw, int ddir, + u64 attr_ptr, u64 attr_type_mask) +{ + struct io_uring_attr_pi pi_attr; + struct io_async_rw *io; + int ret; + + if (copy_from_user(&pi_attr, u64_to_user_ptr(attr_ptr), + sizeof(pi_attr))) + return -EFAULT; + + if (pi_attr.rsvd) + return -EINVAL; + + io = req->async_data; + io->meta.flags = pi_attr.flags; + io->meta.app_tag = pi_attr.app_tag; + io->meta.seed = pi_attr.seed; + ret = import_ubuf(ddir, u64_to_user_ptr(pi_attr.addr), + pi_attr.len, &io->meta.iter); + if (unlikely(ret < 0)) + return ret; + rw->kiocb.ki_flags |= IOCB_HAS_METADATA; + io_meta_save_state(io); + return ret; +} + static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe, int ddir, bool do_import) { struct io_rw *rw = io_kiocb_to_cmd(req, struct io_rw); unsigned ioprio; + u64 attr_type_mask; int ret; rw->kiocb.ki_pos = READ_ONCE(sqe->off); @@ -279,11 +321,28 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe, rw->kiocb.ki_ioprio = get_current_ioprio(); } rw->kiocb.dio_complete = NULL; + rw->kiocb.ki_flags = 0; rw->addr = READ_ONCE(sqe->addr); rw->len = READ_ONCE(sqe->len); rw->flags = READ_ONCE(sqe->rw_flags); - return io_prep_rw_setup(req, ddir, do_import); + ret = io_prep_rw_setup(req, ddir, do_import); + + if (unlikely(ret)) + return ret; + + attr_type_mask = READ_ONCE(sqe->attr_type_mask); + if (attr_type_mask) { + u64 attr_ptr; + + /* only PI attribute is supported currently */ + if (attr_type_mask != IORING_RW_ATTR_FLAG_PI) + return -EINVAL; + + attr_ptr = READ_ONCE(sqe->attr_ptr); + ret = io_prep_rw_pi(req, rw, ddir, attr_ptr, attr_type_mask); + } + return ret; } int io_prep_read(struct io_kiocb *req, const struct io_uring_sqe *sqe) @@ -409,7 +468,9 @@ static inline loff_t *io_kiocb_update_pos(struct io_kiocb *req) static void io_resubmit_prep(struct io_kiocb *req) { struct io_async_rw *io = req->async_data; + struct io_rw *rw = io_kiocb_to_cmd(req, struct io_rw); + io_meta_restore(io, &rw->kiocb); iov_iter_restore(&io->iter, &io->iter_state); } @@ -744,6 +805,10 @@ static bool io_rw_should_retry(struct io_kiocb *req) if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI)) return false; + /* never retry for meta io */ + if (kiocb->ki_flags & IOCB_HAS_METADATA) + return false; + /* * just use poll if we can, and don't attempt if the fs doesn't * support callback based unlocks @@ -794,7 +859,7 @@ static int io_rw_init_file(struct io_kiocb *req, fmode_t mode, int rw_type) if (!(req->flags & REQ_F_FIXED_FILE)) req->flags |= io_file_get_flags(file); - kiocb->ki_flags = file->f_iocb_flags; + kiocb->ki_flags |= file->f_iocb_flags; ret = kiocb_set_rw_flags(kiocb, rw->flags, rw_type); if (unlikely(ret)) return ret; @@ -828,6 +893,18 @@ static int io_rw_init_file(struct io_kiocb *req, fmode_t mode, int rw_type) kiocb->ki_complete = io_complete_rw; } + if (kiocb->ki_flags & IOCB_HAS_METADATA) { + struct io_async_rw *io = req->async_data; + + /* + * We have a union of meta fields with wpq used for buffered-io + * in io_async_rw, so fail it here. + */ + if (!(req->file->f_flags & O_DIRECT)) + return -EOPNOTSUPP; + kiocb->private = &io->meta; + } + return 0; } @@ -902,6 +979,7 @@ static int __io_read(struct io_kiocb *req, unsigned int issue_flags) * manually if we need to. */ iov_iter_restore(&io->iter, &io->iter_state); + io_meta_restore(io, kiocb); do { /* @@ -1125,6 +1203,7 @@ int io_write(struct io_kiocb *req, unsigned int issue_flags) } else { ret_eagain: iov_iter_restore(&io->iter, &io->iter_state); + io_meta_restore(io, kiocb); if (kiocb->ki_flags & IOCB_WRITE) io_req_end_write(req); return -EAGAIN; diff --git a/io_uring/rw.h b/io_uring/rw.h index 3f432dc75441..2d7656bd268d 100644 --- a/io_uring/rw.h +++ b/io_uring/rw.h @@ -2,6 +2,11 @@ #include +struct io_meta_state { + u32 seed; + struct iov_iter_state iter_meta; +}; + struct io_async_rw { size_t bytes_done; struct iov_iter iter; @@ -9,7 +14,14 @@ struct io_async_rw { struct iovec fast_iov; struct iovec *free_iovec; int free_iov_nr; - struct wait_page_queue wpq; + /* wpq is for buffered io, while meta fields are used with direct io */ + union { + struct wait_page_queue wpq; + struct { + struct uio_meta meta; + struct io_meta_state meta_state; + }; + }; }; int io_prep_read_fixed(struct io_kiocb *req, const struct io_uring_sqe *sqe);