diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-05-02 03:03:06 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-05-02 03:03:06 +0300 |
commit | cf0185308c41a307a4e7b37b6690d30735fa16a6 (patch) | |
tree | cf2ccc8354d6fccb4650318ccd8b817a8155268a | |
parent | 052c467cb58748e302a95546925928e637025acc (diff) | |
parent | 2fb3e82284fca40afbde5351907f0a5b3be717f9 (diff) | |
download | linux-cf0185308c41a307a4e7b37b6690d30735fa16a6.tar.xz |
Merge tag 'io_uring-5.7-2020-05-01' of git://git.kernel.dk/linux-block
Pull io_uring fixes from Jens Axboe:
- Fix for statx not grabbing the file table, making AT_EMPTY_PATH fail
- Cover a few cases where async poll can handle retry, eliminating the
need for an async thread
- fallback request busy/free fix (Bijan)
- syzbot reported SQPOLL thread exit fix for non-preempt (Xiaoguang)
- Fix extra put of req for sync_file_range (Pavel)
- Always punt splice async. We'll improve this for 5.8, but wanted to
eliminate the inode mutex lock from the non-blocking path for 5.7
(Pavel)
* tag 'io_uring-5.7-2020-05-01' of git://git.kernel.dk/linux-block:
io_uring: punt splice async because of inode mutex
io_uring: check non-sync defer_list carefully
io_uring: fix extra put in sync_file_range()
io_uring: use cond_resched() in io_ring_ctx_wait_and_kill()
io_uring: use proper references for fallback_req locking
io_uring: only force async punt if poll based retry can't handle it
io_uring: enable poll retry for any file with ->read_iter / ->write_iter
io_uring: statx must grab the file table for valid fd
-rw-r--r-- | fs/io_uring.c | 58 |
1 files changed, 31 insertions, 27 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index c687f57fb651..0b91b0631173 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -524,6 +524,7 @@ enum { REQ_F_OVERFLOW_BIT, REQ_F_POLLED_BIT, REQ_F_BUFFER_SELECTED_BIT, + REQ_F_NO_FILE_TABLE_BIT, /* not a real bit, just to check we're not overflowing the space */ __REQ_F_LAST_BIT, @@ -577,6 +578,8 @@ enum { REQ_F_POLLED = BIT(REQ_F_POLLED_BIT), /* buffer already selected */ REQ_F_BUFFER_SELECTED = BIT(REQ_F_BUFFER_SELECTED_BIT), + /* doesn't need file table for this request */ + REQ_F_NO_FILE_TABLE = BIT(REQ_F_NO_FILE_TABLE_BIT), }; struct async_poll { @@ -799,6 +802,7 @@ static const struct io_op_def io_op_defs[] = { .needs_file = 1, .fd_non_neg = 1, .needs_fs = 1, + .file_table = 1, }, [IORING_OP_READ] = { .needs_mm = 1, @@ -1291,7 +1295,7 @@ static struct io_kiocb *io_get_fallback_req(struct io_ring_ctx *ctx) struct io_kiocb *req; req = ctx->fallback_req; - if (!test_and_set_bit_lock(0, (unsigned long *) ctx->fallback_req)) + if (!test_and_set_bit_lock(0, (unsigned long *) &ctx->fallback_req)) return req; return NULL; @@ -1378,7 +1382,7 @@ static void __io_free_req(struct io_kiocb *req) if (likely(!io_is_fallback_req(req))) kmem_cache_free(req_cachep, req); else - clear_bit_unlock(0, (unsigned long *) req->ctx->fallback_req); + clear_bit_unlock(0, (unsigned long *) &req->ctx->fallback_req); } struct req_batch { @@ -2034,7 +2038,7 @@ static struct file *__io_file_get(struct io_submit_state *state, int fd) * any file. For now, just ensure that anything potentially problematic is done * inline. */ -static bool io_file_supports_async(struct file *file) +static bool io_file_supports_async(struct file *file, int rw) { umode_t mode = file_inode(file)->i_mode; @@ -2043,7 +2047,13 @@ static bool io_file_supports_async(struct file *file) if (S_ISREG(mode) && file->f_op != &io_uring_fops) return true; - return false; + if (!(file->f_mode & FMODE_NOWAIT)) + return false; + + if (rw == READ) + return file->f_op->read_iter != NULL; + + return file->f_op->write_iter != NULL; } static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe, @@ -2571,7 +2581,7 @@ static int io_read(struct io_kiocb *req, bool force_nonblock) * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so * we know to async punt it even if it was opened O_NONBLOCK */ - if (force_nonblock && !io_file_supports_async(req->file)) + if (force_nonblock && !io_file_supports_async(req->file, READ)) goto copy_iov; iov_count = iov_iter_count(&iter); @@ -2594,7 +2604,8 @@ copy_iov: if (ret) goto out_free; /* any defer here is final, must blocking retry */ - if (!(req->flags & REQ_F_NOWAIT)) + if (!(req->flags & REQ_F_NOWAIT) && + !file_can_poll(req->file)) req->flags |= REQ_F_MUST_PUNT; return -EAGAIN; } @@ -2662,7 +2673,7 @@ static int io_write(struct io_kiocb *req, bool force_nonblock) * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so * we know to async punt it even if it was opened O_NONBLOCK */ - if (force_nonblock && !io_file_supports_async(req->file)) + if (force_nonblock && !io_file_supports_async(req->file, WRITE)) goto copy_iov; /* file path doesn't support NOWAIT for non-direct_IO */ @@ -2716,7 +2727,8 @@ copy_iov: if (ret) goto out_free; /* any defer here is final, must blocking retry */ - req->flags |= REQ_F_MUST_PUNT; + if (!file_can_poll(req->file)) + req->flags |= REQ_F_MUST_PUNT; return -EAGAIN; } } @@ -2756,15 +2768,6 @@ static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return 0; } -static bool io_splice_punt(struct file *file) -{ - if (get_pipe_info(file)) - return false; - if (!io_file_supports_async(file)) - return true; - return !(file->f_flags & O_NONBLOCK); -} - static int io_splice(struct io_kiocb *req, bool force_nonblock) { struct io_splice *sp = &req->splice; @@ -2774,11 +2777,8 @@ static int io_splice(struct io_kiocb *req, bool force_nonblock) loff_t *poff_in, *poff_out; long ret; - if (force_nonblock) { - if (io_splice_punt(in) || io_splice_punt(out)) - return -EAGAIN; - flags |= SPLICE_F_NONBLOCK; - } + if (force_nonblock) + return -EAGAIN; poff_in = (sp->off_in == -1) ? NULL : &sp->off_in; poff_out = (sp->off_out == -1) ? NULL : &sp->off_out; @@ -3355,8 +3355,12 @@ static int io_statx(struct io_kiocb *req, bool force_nonblock) struct kstat stat; int ret; - if (force_nonblock) + if (force_nonblock) { + /* only need file table for an actual valid fd */ + if (ctx->dfd == -1 || ctx->dfd == AT_FDCWD) + req->flags |= REQ_F_NO_FILE_TABLE; return -EAGAIN; + } if (vfs_stat_set_lookup_flags(&lookup_flags, ctx->how.flags)) return -EINVAL; @@ -3502,7 +3506,7 @@ static void io_sync_file_range_finish(struct io_wq_work **workptr) if (io_req_cancelled(req)) return; __io_sync_file_range(req); - io_put_req(req); /* put submission ref */ + io_steal_work(req, workptr); } static int io_sync_file_range(struct io_kiocb *req, bool force_nonblock) @@ -5015,7 +5019,7 @@ static int io_req_defer(struct io_kiocb *req, const struct io_uring_sqe *sqe) int ret; /* Still need defer if there is pending req in defer list. */ - if (!req_need_defer(req) && list_empty(&ctx->defer_list)) + if (!req_need_defer(req) && list_empty_careful(&ctx->defer_list)) return 0; if (!req->io && io_alloc_async_ctx(req)) @@ -5429,7 +5433,7 @@ static int io_grab_files(struct io_kiocb *req) int ret = -EBADF; struct io_ring_ctx *ctx = req->ctx; - if (req->work.files) + if (req->work.files || (req->flags & REQ_F_NO_FILE_TABLE)) return 0; if (!ctx->ring_file) return -EBADF; @@ -7327,7 +7331,7 @@ static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx) * it could cause shutdown to hang. */ while (ctx->sqo_thread && !wq_has_sleeper(&ctx->sqo_wait)) - cpu_relax(); + cond_resched(); io_kill_timeouts(ctx); io_poll_remove_all(ctx); |