diff options
Diffstat (limited to 'fs')
-rw-r--r-- | fs/io-wq.c | 30 | ||||
-rw-r--r-- | fs/io-wq.h | 3 | ||||
-rw-r--r-- | fs/io_uring.c | 116 |
3 files changed, 141 insertions, 8 deletions
diff --git a/fs/io-wq.c b/fs/io-wq.c index 37863879e987..253c04a40db5 100644 --- a/fs/io-wq.c +++ b/fs/io-wq.c @@ -52,6 +52,7 @@ struct io_worker { struct rcu_head rcu; struct mm_struct *mm; + struct files_struct *restore_files; }; struct io_wq_nulls_list { @@ -126,22 +127,36 @@ static void io_worker_release(struct io_worker *worker) */ static bool __io_worker_unuse(struct io_wqe *wqe, struct io_worker *worker) { + bool dropped_lock = false; + + if (current->files != worker->restore_files) { + __acquire(&wqe->lock); + spin_unlock_irq(&wqe->lock); + dropped_lock = true; + + task_lock(current); + current->files = worker->restore_files; + task_unlock(current); + } + /* * If we have an active mm, we need to drop the wq lock before unusing * it. If we do, return true and let the caller retry the idle loop. */ if (worker->mm) { - __acquire(&wqe->lock); - spin_unlock_irq(&wqe->lock); + if (!dropped_lock) { + __acquire(&wqe->lock); + spin_unlock_irq(&wqe->lock); + dropped_lock = true; + } __set_current_state(TASK_RUNNING); set_fs(KERNEL_DS); unuse_mm(worker->mm); mmput(worker->mm); worker->mm = NULL; - return true; } - return false; + return dropped_lock; } static void io_worker_exit(struct io_worker *worker) @@ -189,6 +204,7 @@ static void io_worker_start(struct io_wqe *wqe, struct io_worker *worker) current->flags |= PF_IO_WORKER; worker->flags |= (IO_WORKER_F_UP | IO_WORKER_F_RUNNING); + worker->restore_files = current->files; atomic_inc(&wqe->nr_running); } @@ -291,6 +307,12 @@ static void io_worker_handle_work(struct io_worker *worker) if (!work) break; next: + if ((work->flags & IO_WQ_WORK_NEEDS_FILES) && + current->files != work->files) { + task_lock(current); + current->files = work->files; + task_unlock(current); + } if ((work->flags & IO_WQ_WORK_NEEDS_USER) && !worker->mm && wq->mm && mmget_not_zero(wq->mm)) { use_mm(wq->mm); diff --git a/fs/io-wq.h b/fs/io-wq.h index be8f22c8937b..e93f764b1fa4 100644 --- a/fs/io-wq.h +++ b/fs/io-wq.h @@ -8,6 +8,7 @@ enum { IO_WQ_WORK_HAS_MM = 2, IO_WQ_WORK_HASHED = 4, IO_WQ_WORK_NEEDS_USER = 8, + IO_WQ_WORK_NEEDS_FILES = 16, IO_WQ_HASH_SHIFT = 24, /* upper 8 bits are used for hash key */ }; @@ -22,12 +23,14 @@ struct io_wq_work { struct list_head list; void (*func)(struct io_wq_work **); unsigned flags; + struct files_struct *files; }; #define INIT_IO_WORK(work, _func) \ do { \ (work)->func = _func; \ (work)->flags = 0; \ + (work)->files = NULL; \ } while (0) \ struct io_wq *io_wq_create(unsigned concurrency, struct mm_struct *mm); diff --git a/fs/io_uring.c b/fs/io_uring.c index d94bd4e3a60e..6e1523567920 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -196,6 +196,8 @@ struct io_ring_ctx { struct list_head defer_list; struct list_head timeout_list; + + wait_queue_head_t inflight_wait; } ____cacheline_aligned_in_smp; /* IO offload */ @@ -250,6 +252,9 @@ struct io_ring_ctx { */ struct list_head poll_list; struct list_head cancel_list; + + spinlock_t inflight_lock; + struct list_head inflight_list; } ____cacheline_aligned_in_smp; #if defined(CONFIG_UNIX) @@ -259,6 +264,8 @@ struct io_ring_ctx { struct sqe_submit { const struct io_uring_sqe *sqe; + struct file *ring_file; + int ring_fd; u32 sequence; bool has_user; bool in_async; @@ -317,10 +324,13 @@ struct io_kiocb { #define REQ_F_TIMEOUT 1024 /* timeout request */ #define REQ_F_ISREG 2048 /* regular file */ #define REQ_F_MUST_PUNT 4096 /* must be punted even for NONBLOCK */ +#define REQ_F_INFLIGHT 8192 /* on inflight list */ u64 user_data; u32 result; u32 sequence; + struct list_head inflight_entry; + struct io_wq_work work; }; @@ -401,6 +411,9 @@ static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) INIT_LIST_HEAD(&ctx->cancel_list); INIT_LIST_HEAD(&ctx->defer_list); INIT_LIST_HEAD(&ctx->timeout_list); + init_waitqueue_head(&ctx->inflight_wait); + spin_lock_init(&ctx->inflight_lock); + INIT_LIST_HEAD(&ctx->inflight_list); return ctx; } @@ -670,9 +683,20 @@ static void io_free_req_many(struct io_ring_ctx *ctx, void **reqs, int *nr) static void __io_free_req(struct io_kiocb *req) { + struct io_ring_ctx *ctx = req->ctx; + if (req->file && !(req->flags & REQ_F_FIXED_FILE)) fput(req->file); - percpu_ref_put(&req->ctx->refs); + if (req->flags & REQ_F_INFLIGHT) { + unsigned long flags; + + spin_lock_irqsave(&ctx->inflight_lock, flags); + list_del(&req->inflight_entry); + if (waitqueue_active(&ctx->inflight_wait)) + wake_up(&ctx->inflight_wait); + spin_unlock_irqrestore(&ctx->inflight_lock, flags); + } + percpu_ref_put(&ctx->refs); kmem_cache_free(req_cachep, req); } @@ -2276,6 +2300,30 @@ static int io_req_set_file(struct io_ring_ctx *ctx, const struct sqe_submit *s, return 0; } +static int io_grab_files(struct io_ring_ctx *ctx, struct io_kiocb *req) +{ + int ret = -EBADF; + + rcu_read_lock(); + spin_lock_irq(&ctx->inflight_lock); + /* + * We use the f_ops->flush() handler to ensure that we can flush + * out work accessing these files if the fd is closed. Check if + * the fd has changed since we started down this path, and disallow + * this operation if it has. + */ + if (fcheck(req->submit.ring_fd) == req->submit.ring_file) { + list_add(&req->inflight_entry, &ctx->inflight_list); + req->flags |= REQ_F_INFLIGHT; + req->work.files = current->files; + ret = 0; + } + spin_unlock_irq(&ctx->inflight_lock); + rcu_read_unlock(); + + return ret; +} + static int __io_queue_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req, struct sqe_submit *s) { @@ -2295,17 +2343,25 @@ static int __io_queue_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req, if (sqe_copy) { s->sqe = sqe_copy; memcpy(&req->submit, s, sizeof(*s)); - io_queue_async_work(ctx, req); + if (req->work.flags & IO_WQ_WORK_NEEDS_FILES) { + ret = io_grab_files(ctx, req); + if (ret) { + kfree(sqe_copy); + goto err; + } + } /* * Queued up for async execution, worker will release * submit reference when the iocb is actually submitted. */ + io_queue_async_work(ctx, req); return 0; } } /* drop submission reference */ +err: io_put_req(req, NULL); /* and drop final reference, if we failed */ @@ -2509,6 +2565,7 @@ static bool io_get_sqring(struct io_ring_ctx *ctx, struct sqe_submit *s) head = READ_ONCE(sq_array[head & ctx->sq_mask]); if (head < ctx->sq_entries) { + s->ring_file = NULL; s->sqe = &ctx->sq_sqes[head]; s->sequence = ctx->cached_sq_head; ctx->cached_sq_head++; @@ -2708,7 +2765,8 @@ static int io_sq_thread(void *data) return 0; } -static int io_ring_submit(struct io_ring_ctx *ctx, unsigned int to_submit) +static int io_ring_submit(struct io_ring_ctx *ctx, unsigned int to_submit, + struct file *ring_file, int ring_fd) { struct io_submit_state state, *statep = NULL; struct io_kiocb *link = NULL; @@ -2750,9 +2808,11 @@ static int io_ring_submit(struct io_ring_ctx *ctx, unsigned int to_submit) } out: + s.ring_file = ring_file; s.has_user = true; s.in_async = false; s.needs_fixed_file = false; + s.ring_fd = ring_fd; submit++; trace_io_uring_submit_sqe(ctx, true, false); io_submit_sqe(ctx, &s, statep, &link); @@ -3714,6 +3774,53 @@ static int io_uring_release(struct inode *inode, struct file *file) return 0; } +static void io_uring_cancel_files(struct io_ring_ctx *ctx, + struct files_struct *files) +{ + struct io_kiocb *req; + DEFINE_WAIT(wait); + + while (!list_empty_careful(&ctx->inflight_list)) { + enum io_wq_cancel ret = IO_WQ_CANCEL_NOTFOUND; + + spin_lock_irq(&ctx->inflight_lock); + list_for_each_entry(req, &ctx->inflight_list, inflight_entry) { + if (req->work.files == files) { + ret = io_wq_cancel_work(ctx->io_wq, &req->work); + break; + } + } + if (ret == IO_WQ_CANCEL_RUNNING) + prepare_to_wait(&ctx->inflight_wait, &wait, + TASK_UNINTERRUPTIBLE); + + spin_unlock_irq(&ctx->inflight_lock); + + /* + * We need to keep going until we get NOTFOUND. We only cancel + * one work at the time. + * + * If we get CANCEL_RUNNING, then wait for a work to complete + * before continuing. + */ + if (ret == IO_WQ_CANCEL_OK) + continue; + else if (ret != IO_WQ_CANCEL_RUNNING) + break; + schedule(); + } +} + +static int io_uring_flush(struct file *file, void *data) +{ + struct io_ring_ctx *ctx = file->private_data; + + io_uring_cancel_files(ctx, data); + if (fatal_signal_pending(current) || (current->flags & PF_EXITING)) + io_wq_cancel_all(ctx->io_wq); + return 0; +} + static int io_uring_mmap(struct file *file, struct vm_area_struct *vma) { loff_t offset = (loff_t) vma->vm_pgoff << PAGE_SHIFT; @@ -3782,7 +3889,7 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, to_submit = min(to_submit, ctx->sq_entries); mutex_lock(&ctx->uring_lock); - submitted = io_ring_submit(ctx, to_submit); + submitted = io_ring_submit(ctx, to_submit, f.file, fd); mutex_unlock(&ctx->uring_lock); } if (flags & IORING_ENTER_GETEVENTS) { @@ -3805,6 +3912,7 @@ out_fput: static const struct file_operations io_uring_fops = { .release = io_uring_release, + .flush = io_uring_flush, .mmap = io_uring_mmap, .poll = io_uring_poll, .fasync = io_uring_fasync, |