From: Pavel Begunkov Date: Thu, 10 Jun 2021 15:37:37 +0000 (+0100) Subject: io_uring: change registration/upd/rsrc tagging ABI X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=992da01aa932b432ef8dc3885fa76415b5dbe43f;p=uclinux-h8%2Flinux.git io_uring: change registration/upd/rsrc tagging ABI There are ABI moments about recently added rsrc registration/update and tagging that might become a nuisance in the future. First, IORING_REGISTER_RSRC[_UPD] hide different types of resources under it, so breaks fine control over them by restrictions. It works for now, but once those are wanted under restrictions it would require a rework. It was also inconvenient trying to fit a new resource not supporting all the features (e.g. dynamic update) into the interface, so better to return to IORING_REGISTER_* top level dispatching. Second, register/update were considered to accept a type of resource, however that's not a good idea because there might be several ways of registration of a single resource type, e.g. we may want to add non-contig buffers or anything more exquisite as dma mapped memory. So, remove IORING_RSRC_[FILE,BUFFER] out of the ABI, and place them internally for now to limit changes. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/9b554897a7c17ad6e3becc48dfed2f7af9f423d5.1623339162.git.asml.silence@gmail.com Signed-off-by: Jens Axboe --- diff --git a/fs/io_uring.c b/fs/io_uring.c index 42380ed563c4..663fef3d56df 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -783,6 +783,11 @@ struct io_task_work { task_work_func_t func; }; +enum { + IORING_RSRC_FILE = 0, + IORING_RSRC_BUFFER = 1, +}; + /* * NOTE! Each of the iocb union members has the file pointer * as the first entry in their struct definition. So you can @@ -9911,7 +9916,7 @@ static int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg, } static int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg, - unsigned size) + unsigned size, unsigned type) { struct io_uring_rsrc_update2 up; @@ -9919,13 +9924,13 @@ static int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg, return -EINVAL; if (copy_from_user(&up, arg, sizeof(up))) return -EFAULT; - if (!up.nr) + if (!up.nr || up.resv) return -EINVAL; - return __io_register_rsrc_update(ctx, up.type, &up, up.nr); + return __io_register_rsrc_update(ctx, type, &up, up.nr); } static int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg, - unsigned int size) + unsigned int size, unsigned int type) { struct io_uring_rsrc_register rr; @@ -9936,10 +9941,10 @@ static int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg, memset(&rr, 0, sizeof(rr)); if (copy_from_user(&rr, arg, size)) return -EFAULT; - if (!rr.nr) + if (!rr.nr || rr.resv || rr.resv2) return -EINVAL; - switch (rr.type) { + switch (type) { case IORING_RSRC_FILE: return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data), rr.nr, u64_to_user_ptr(rr.tags)); @@ -9961,8 +9966,10 @@ static bool io_register_op_must_quiesce(int op) case IORING_REGISTER_PROBE: case IORING_REGISTER_PERSONALITY: case IORING_UNREGISTER_PERSONALITY: - case IORING_REGISTER_RSRC: - case IORING_REGISTER_RSRC_UPDATE: + case IORING_REGISTER_FILES2: + case IORING_REGISTER_FILES_UPDATE2: + case IORING_REGISTER_BUFFERS2: + case IORING_REGISTER_BUFFERS_UPDATE: return false; default: return true; @@ -10088,11 +10095,19 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode, case IORING_REGISTER_RESTRICTIONS: ret = io_register_restrictions(ctx, arg, nr_args); break; - case IORING_REGISTER_RSRC: - ret = io_register_rsrc(ctx, arg, nr_args); + case IORING_REGISTER_FILES2: + ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_FILE); + break; + case IORING_REGISTER_FILES_UPDATE2: + ret = io_register_rsrc_update(ctx, arg, nr_args, + IORING_RSRC_FILE); + break; + case IORING_REGISTER_BUFFERS2: + ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_BUFFER); break; - case IORING_REGISTER_RSRC_UPDATE: - ret = io_register_rsrc_update(ctx, arg, nr_args); + case IORING_REGISTER_BUFFERS_UPDATE: + ret = io_register_rsrc_update(ctx, arg, nr_args, + IORING_RSRC_BUFFER); break; default: ret = -EINVAL; diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index e1ae46683301..48b4ddcd56ff 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -298,8 +298,12 @@ enum { IORING_UNREGISTER_PERSONALITY = 10, IORING_REGISTER_RESTRICTIONS = 11, IORING_REGISTER_ENABLE_RINGS = 12, - IORING_REGISTER_RSRC = 13, - IORING_REGISTER_RSRC_UPDATE = 14, + + /* extended with tagging */ + IORING_REGISTER_FILES2 = 13, + IORING_REGISTER_FILES_UPDATE2 = 14, + IORING_REGISTER_BUFFERS2 = 15, + IORING_REGISTER_BUFFERS_UPDATE = 16, /* this goes last */ IORING_REGISTER_LAST @@ -312,14 +316,10 @@ struct io_uring_files_update { __aligned_u64 /* __s32 * */ fds; }; -enum { - IORING_RSRC_FILE = 0, - IORING_RSRC_BUFFER = 1, -}; - struct io_uring_rsrc_register { - __u32 type; __u32 nr; + __u32 resv; + __u64 resv2; __aligned_u64 data; __aligned_u64 tags; }; @@ -335,8 +335,8 @@ struct io_uring_rsrc_update2 { __u32 resv; __aligned_u64 data; __aligned_u64 tags; - __u32 type; __u32 nr; + __u32 resv2; }; /* Skip updating fd indexes set to this value in the fd table */