diff options
Diffstat (limited to 'io_uring/io_uring.c')
-rw-r--r-- | io_uring/io_uring.c | 108 |
1 files changed, 56 insertions, 52 deletions
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index ed254076c723..9839016f82ea 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -271,6 +271,7 @@ static __cold void io_fallback_req_func(struct work_struct *work) struct io_kiocb *req, *tmp; struct io_tw_state ts = { .locked = true, }; + percpu_ref_get(&ctx->refs); mutex_lock(&ctx->uring_lock); llist_for_each_entry_safe(req, tmp, node, io_task_work.node) req->io_task_work.func(req, &ts); @@ -278,6 +279,7 @@ static __cold void io_fallback_req_func(struct work_struct *work) return; io_submit_flush_completions(ctx); mutex_unlock(&ctx->uring_lock); + percpu_ref_put(&ctx->refs); } static int io_alloc_hash_table(struct io_hash_table *table, unsigned bits) @@ -325,6 +327,7 @@ static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) INIT_LIST_HEAD(&ctx->sqd_list); INIT_LIST_HEAD(&ctx->cq_overflow_list); INIT_LIST_HEAD(&ctx->io_buffers_cache); + INIT_HLIST_HEAD(&ctx->io_buf_list); io_alloc_cache_init(&ctx->rsrc_node_cache, IO_NODE_ALLOC_CACHE_MAX, sizeof(struct io_rsrc_node)); io_alloc_cache_init(&ctx->apoll_cache, IO_ALLOC_CACHE_MAX, @@ -558,7 +561,7 @@ static void io_eventfd_ops(struct rcu_head *rcu) int ops = atomic_xchg(&ev_fd->ops, 0); if (ops & BIT(IO_EVENTFD_OP_SIGNAL_BIT)) - eventfd_signal_mask(ev_fd->cq_ev_fd, 1, EPOLL_URING_WAKE); + eventfd_signal_mask(ev_fd->cq_ev_fd, EPOLL_URING_WAKE); /* IO_EVENTFD_OP_FREE_BIT may not be set here depending on callback * ordering in a race but if references are 0 we know we have to free @@ -594,7 +597,7 @@ static void io_eventfd_signal(struct io_ring_ctx *ctx) goto out; if (likely(eventfd_signal_allowed())) { - eventfd_signal_mask(ev_fd->cq_ev_fd, 1, EPOLL_URING_WAKE); + eventfd_signal_mask(ev_fd->cq_ev_fd, EPOLL_URING_WAKE); } else { atomic_inc(&ev_fd->refs); if (!atomic_fetch_or(BIT(IO_EVENTFD_OP_SIGNAL_BIT), &ev_fd->ops)) @@ -2666,7 +2669,7 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0; } -static void io_mem_free(void *ptr) +void io_mem_free(void *ptr) { if (!ptr) return; @@ -2697,6 +2700,7 @@ static void *__io_uaddr_map(struct page ***pages, unsigned short *npages, { struct page **page_array; unsigned int nr_pages; + void *page_addr; int ret, i; *npages = 0; @@ -2718,27 +2722,29 @@ err: io_pages_free(&page_array, ret > 0 ? ret : 0); return ret < 0 ? ERR_PTR(ret) : ERR_PTR(-EFAULT); } - /* - * Should be a single page. If the ring is small enough that we can - * use a normal page, that is fine. If we need multiple pages, then - * userspace should use a huge page. That's the only way to guarantee - * that we get contigious memory, outside of just being lucky or - * (currently) having low memory fragmentation. - */ - if (page_array[0] != page_array[ret - 1]) - goto err; - /* - * Can't support mapping user allocated ring memory on 32-bit archs - * where it could potentially reside in highmem. Just fail those with - * -EINVAL, just like we did on kernels that didn't support this - * feature. - */ + page_addr = page_address(page_array[0]); for (i = 0; i < nr_pages; i++) { - if (PageHighMem(page_array[i])) { - ret = -EINVAL; + ret = -EINVAL; + + /* + * Can't support mapping user allocated ring memory on 32-bit + * archs where it could potentially reside in highmem. Just + * fail those with -EINVAL, just like we did on kernels that + * didn't support this feature. + */ + if (PageHighMem(page_array[i])) goto err; - } + + /* + * No support for discontig pages for now, should either be a + * single normal page, or a huge page. Later on we can add + * support for remapping discontig pages, for now we will + * just fail them with EINVAL. + */ + if (page_address(page_array[i]) != page_addr) + goto err; + page_addr += PAGE_SIZE; } *pages = page_array; @@ -2775,7 +2781,7 @@ static void io_rings_free(struct io_ring_ctx *ctx) } } -static void *io_mem_alloc(size_t size) +void *io_mem_alloc(size_t size) { gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP; void *ret; @@ -2947,6 +2953,7 @@ static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx) ctx->mm_account = NULL; } io_rings_free(ctx); + io_kbuf_mmap_list_free(ctx); percpu_ref_exit(&ctx->refs); free_uid(ctx->user); @@ -3141,12 +3148,7 @@ static __cold void io_ring_exit_work(struct work_struct *work) init_completion(&exit.completion); init_task_work(&exit.task_work, io_tctx_exit_cb); exit.ctx = ctx; - /* - * Some may use context even when all refs and requests have been put, - * and they are free to do so while still holding uring_lock or - * completion_lock, see io_req_task_submit(). Apart from other work, - * this lock/unlock section also waits them to finish. - */ + mutex_lock(&ctx->uring_lock); while (!list_empty(&ctx->tctx_list)) { WARN_ON_ONCE(time_after(jiffies, timeout)); @@ -3475,25 +3477,27 @@ static void *io_uring_validate_mmap_request(struct file *file, struct page *page; void *ptr; - /* Don't allow mmap if the ring was setup without it */ - if (ctx->flags & IORING_SETUP_NO_MMAP) - return ERR_PTR(-EINVAL); - switch (offset & IORING_OFF_MMAP_MASK) { case IORING_OFF_SQ_RING: case IORING_OFF_CQ_RING: + /* Don't allow mmap if the ring was setup without it */ + if (ctx->flags & IORING_SETUP_NO_MMAP) + return ERR_PTR(-EINVAL); ptr = ctx->rings; break; case IORING_OFF_SQES: + /* Don't allow mmap if the ring was setup without it */ + if (ctx->flags & IORING_SETUP_NO_MMAP) + return ERR_PTR(-EINVAL); ptr = ctx->sq_sqes; break; case IORING_OFF_PBUF_RING: { unsigned int bgid; bgid = (offset & ~IORING_OFF_MMAP_MASK) >> IORING_OFF_PBUF_SHIFT; - mutex_lock(&ctx->uring_lock); + rcu_read_lock(); ptr = io_pbuf_get_address(ctx, bgid); - mutex_unlock(&ctx->uring_lock); + rcu_read_unlock(); if (!ptr) return ERR_PTR(-EINVAL); break; @@ -3645,7 +3649,7 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, size_t, argsz) { struct io_ring_ctx *ctx; - struct fd f; + struct file *file; long ret; if (unlikely(flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP | @@ -3663,20 +3667,19 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, if (unlikely(!tctx || fd >= IO_RINGFD_REG_MAX)) return -EINVAL; fd = array_index_nospec(fd, IO_RINGFD_REG_MAX); - f.file = tctx->registered_rings[fd]; - f.flags = 0; - if (unlikely(!f.file)) + file = tctx->registered_rings[fd]; + if (unlikely(!file)) return -EBADF; } else { - f = fdget(fd); - if (unlikely(!f.file)) + file = fget(fd); + if (unlikely(!file)) return -EBADF; ret = -EOPNOTSUPP; - if (unlikely(!io_is_uring_fops(f.file))) + if (unlikely(!io_is_uring_fops(file))) goto out; } - ctx = f.file->private_data; + ctx = file->private_data; ret = -EBADFD; if (unlikely(ctx->flags & IORING_SETUP_R_DISABLED)) goto out; @@ -3770,7 +3773,8 @@ iopoll_locked: } } out: - fdput(f); + if (!(flags & IORING_ENTER_REGISTERED_RING)) + fput(file); return ret; } @@ -4611,7 +4615,7 @@ SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode, { struct io_ring_ctx *ctx; long ret = -EBADF; - struct fd f; + struct file *file; bool use_registered_ring; use_registered_ring = !!(opcode & IORING_REGISTER_USE_REGISTERED_RING); @@ -4630,27 +4634,27 @@ SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode, if (unlikely(!tctx || fd >= IO_RINGFD_REG_MAX)) return -EINVAL; fd = array_index_nospec(fd, IO_RINGFD_REG_MAX); - f.file = tctx->registered_rings[fd]; - f.flags = 0; - if (unlikely(!f.file)) + file = tctx->registered_rings[fd]; + if (unlikely(!file)) return -EBADF; } else { - f = fdget(fd); - if (unlikely(!f.file)) + file = fget(fd); + if (unlikely(!file)) return -EBADF; ret = -EOPNOTSUPP; - if (!io_is_uring_fops(f.file)) + if (!io_is_uring_fops(file)) goto out_fput; } - ctx = f.file->private_data; + ctx = file->private_data; mutex_lock(&ctx->uring_lock); ret = __io_uring_register(ctx, opcode, arg, nr_args); mutex_unlock(&ctx->uring_lock); trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs, ret); out_fput: - fdput(f); + if (!use_registered_ring) + fput(file); return ret; } |