From 66e85e379d27394398a11d02bd01abf449d7bde3 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Sat, 7 May 2022 10:08:31 -0600 Subject: [PATCH 2/2] io_uring: have multishot accept alloc new fixed file slot Signed-off-by: Jens Axboe --- fs/io_uring.c | 34 ++++++++++++++++++++++++++++++---- 1 file changed, 30 insertions(+), 4 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 13b99040ae90..88b95b828bed 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -258,6 +258,7 @@ struct io_rsrc_put { struct io_file_table { struct io_fixed_file *files; unsigned long *bitmap; + unsigned int alloc_hint; }; struct io_rsrc_node { @@ -5721,8 +5722,7 @@ static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return -EINVAL; accept->file_slot = READ_ONCE(sqe->file_index); - if (accept->file_slot && ((accept->flags & SOCK_CLOEXEC) || - flags & IORING_ACCEPT_MULTISHOT)) + if (accept->file_slot && (accept->flags & SOCK_CLOEXEC)) return -EINVAL; if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK)) return -EINVAL; @@ -5750,6 +5750,18 @@ static inline void io_poll_clean(struct io_kiocb *req) __io_poll_clean(req); } +static int io_file_bitmap_get(struct io_ring_ctx *ctx) +{ + struct io_file_table *table = &ctx->file_table; + int ret; + + ret = find_next_zero_bit(table->bitmap, ctx->nr_user_files, + table->alloc_hint); + if (unlikely(ret == ctx->nr_user_files)) + return -ENFILE; + return ret; +} + static int io_accept(struct io_kiocb *req, unsigned int issue_flags) { struct io_ring_ctx *ctx = req->ctx; @@ -5787,8 +5799,19 @@ static int io_accept(struct io_kiocb *req, unsigned int issue_flags) fd_install(fd, file); ret = fd; } else { - ret = io_install_fixed_file(req, file, issue_flags, - accept->file_slot - 1); + int fixed_slot = accept->file_slot - 1; + + if (req->flags & REQ_F_APOLL_MULTISHOT && accept->file_slot) { + fixed_slot = io_file_bitmap_get(ctx); + if (unlikely(fixed_slot < 0)) { + ret = fixed_slot; + goto err; + } + } + + ret = io_install_fixed_file(req, file, issue_flags, fixed_slot); + if (!ret && req->flags & REQ_F_APOLL_MULTISHOT) + ret = fixed_slot; } if (!(req->flags & REQ_F_APOLL_MULTISHOT)) { @@ -5815,6 +5838,7 @@ static int io_accept(struct io_kiocb *req, unsigned int issue_flags) * since the upper layer who called io_queue_sqe() cannot get errors * happened here. */ +err: io_poll_clean(req); return ret; } @@ -8736,11 +8760,13 @@ static void io_free_file_tables(struct io_file_table *table) static inline void io_file_bitmap_set(struct io_file_table *table, int bit) { __set_bit(bit, table->bitmap); + table->alloc_hint = bit + 1; } static inline void io_file_bitmap_clear(struct io_file_table *table, int bit) { __clear_bit(bit, table->bitmap); + table->alloc_hint = bit; } static void __io_sqe_files_unregister(struct io_ring_ctx *ctx) -- 2.35.1