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1369 lines
31 KiB
1369 lines
31 KiB
// SPDX-License-Identifier: GPL-2.0 |
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#include <linux/kernel.h> |
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#include <linux/errno.h> |
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#include <linux/fs.h> |
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#include <linux/file.h> |
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#include <linux/mm.h> |
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#include <linux/slab.h> |
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#include <linux/nospec.h> |
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#include <linux/hugetlb.h> |
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#include <linux/compat.h> |
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#include <linux/io_uring.h> |
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|
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#include <uapi/linux/io_uring.h> |
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|
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#include "io_uring.h" |
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#include "openclose.h" |
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#include "rsrc.h" |
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|
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struct io_rsrc_update { |
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struct file *file; |
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u64 arg; |
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u32 nr_args; |
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u32 offset; |
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}; |
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|
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static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, |
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struct io_mapped_ubuf **pimu, |
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struct page **last_hpage); |
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|
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#define IO_RSRC_REF_BATCH 100 |
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|
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/* only define max */ |
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#define IORING_MAX_FIXED_FILES (1U << 20) |
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#define IORING_MAX_REG_BUFFERS (1U << 14) |
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|
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void io_rsrc_refs_drop(struct io_ring_ctx *ctx) |
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__must_hold(&ctx->uring_lock) |
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{ |
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if (ctx->rsrc_cached_refs) { |
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io_rsrc_put_node(ctx->rsrc_node, ctx->rsrc_cached_refs); |
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ctx->rsrc_cached_refs = 0; |
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} |
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} |
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|
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int __io_account_mem(struct user_struct *user, unsigned long nr_pages) |
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{ |
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unsigned long page_limit, cur_pages, new_pages; |
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|
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if (!nr_pages) |
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return 0; |
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|
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/* Don't allow more pages than we can safely lock */ |
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page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; |
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|
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cur_pages = atomic_long_read(&user->locked_vm); |
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do { |
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new_pages = cur_pages + nr_pages; |
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if (new_pages > page_limit) |
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return -ENOMEM; |
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} while (!atomic_long_try_cmpxchg(&user->locked_vm, |
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&cur_pages, new_pages)); |
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return 0; |
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} |
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|
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static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) |
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{ |
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if (ctx->user) |
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__io_unaccount_mem(ctx->user, nr_pages); |
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|
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if (ctx->mm_account) |
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atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm); |
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} |
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|
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static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) |
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{ |
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int ret; |
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|
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if (ctx->user) { |
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ret = __io_account_mem(ctx->user, nr_pages); |
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if (ret) |
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return ret; |
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} |
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|
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if (ctx->mm_account) |
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atomic64_add(nr_pages, &ctx->mm_account->pinned_vm); |
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|
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return 0; |
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} |
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|
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static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst, |
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void __user *arg, unsigned index) |
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{ |
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struct iovec __user *src; |
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|
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#ifdef CONFIG_COMPAT |
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if (ctx->compat) { |
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struct compat_iovec __user *ciovs; |
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struct compat_iovec ciov; |
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|
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ciovs = (struct compat_iovec __user *) arg; |
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if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov))) |
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return -EFAULT; |
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|
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dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base); |
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dst->iov_len = ciov.iov_len; |
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return 0; |
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} |
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#endif |
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src = (struct iovec __user *) arg; |
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if (copy_from_user(dst, &src[index], sizeof(*dst))) |
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return -EFAULT; |
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return 0; |
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} |
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|
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static int io_buffer_validate(struct iovec *iov) |
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{ |
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unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1); |
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|
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/* |
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* Don't impose further limits on the size and buffer |
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* constraints here, we'll -EINVAL later when IO is |
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* submitted if they are wrong. |
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*/ |
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if (!iov->iov_base) |
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return iov->iov_len ? -EFAULT : 0; |
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if (!iov->iov_len) |
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return -EFAULT; |
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|
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/* arbitrary limit, but we need something */ |
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if (iov->iov_len > SZ_1G) |
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return -EFAULT; |
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|
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if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp)) |
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return -EOVERFLOW; |
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|
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return 0; |
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} |
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static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot) |
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{ |
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struct io_mapped_ubuf *imu = *slot; |
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unsigned int i; |
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|
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if (imu != ctx->dummy_ubuf) { |
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for (i = 0; i < imu->nr_bvecs; i++) |
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unpin_user_page(imu->bvec[i].bv_page); |
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if (imu->acct_pages) |
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io_unaccount_mem(ctx, imu->acct_pages); |
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kvfree(imu); |
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} |
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*slot = NULL; |
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} |
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void io_rsrc_refs_refill(struct io_ring_ctx *ctx) |
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__must_hold(&ctx->uring_lock) |
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{ |
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ctx->rsrc_cached_refs += IO_RSRC_REF_BATCH; |
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percpu_ref_get_many(&ctx->rsrc_node->refs, IO_RSRC_REF_BATCH); |
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} |
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|
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static void __io_rsrc_put_work(struct io_rsrc_node *ref_node) |
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{ |
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struct io_rsrc_data *rsrc_data = ref_node->rsrc_data; |
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struct io_ring_ctx *ctx = rsrc_data->ctx; |
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struct io_rsrc_put *prsrc, *tmp; |
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|
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list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) { |
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list_del(&prsrc->list); |
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|
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if (prsrc->tag) { |
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if (ctx->flags & IORING_SETUP_IOPOLL) { |
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mutex_lock(&ctx->uring_lock); |
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io_post_aux_cqe(ctx, prsrc->tag, 0, 0, true); |
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mutex_unlock(&ctx->uring_lock); |
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} else { |
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io_post_aux_cqe(ctx, prsrc->tag, 0, 0, true); |
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} |
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} |
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|
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rsrc_data->do_put(ctx, prsrc); |
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kfree(prsrc); |
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} |
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io_rsrc_node_destroy(ref_node); |
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if (atomic_dec_and_test(&rsrc_data->refs)) |
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complete(&rsrc_data->done); |
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} |
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void io_rsrc_put_work(struct work_struct *work) |
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{ |
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struct io_ring_ctx *ctx; |
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struct llist_node *node; |
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ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work); |
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node = llist_del_all(&ctx->rsrc_put_llist); |
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|
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while (node) { |
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struct io_rsrc_node *ref_node; |
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struct llist_node *next = node->next; |
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ref_node = llist_entry(node, struct io_rsrc_node, llist); |
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__io_rsrc_put_work(ref_node); |
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node = next; |
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} |
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} |
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void io_wait_rsrc_data(struct io_rsrc_data *data) |
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{ |
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if (data && !atomic_dec_and_test(&data->refs)) |
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wait_for_completion(&data->done); |
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} |
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|
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void io_rsrc_node_destroy(struct io_rsrc_node *ref_node) |
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{ |
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percpu_ref_exit(&ref_node->refs); |
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kfree(ref_node); |
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} |
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static __cold void io_rsrc_node_ref_zero(struct percpu_ref *ref) |
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{ |
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struct io_rsrc_node *node = container_of(ref, struct io_rsrc_node, refs); |
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struct io_ring_ctx *ctx = node->rsrc_data->ctx; |
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unsigned long flags; |
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bool first_add = false; |
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unsigned long delay = HZ; |
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|
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spin_lock_irqsave(&ctx->rsrc_ref_lock, flags); |
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node->done = true; |
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|
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/* if we are mid-quiesce then do not delay */ |
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if (node->rsrc_data->quiesce) |
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delay = 0; |
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|
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while (!list_empty(&ctx->rsrc_ref_list)) { |
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node = list_first_entry(&ctx->rsrc_ref_list, |
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struct io_rsrc_node, node); |
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/* recycle ref nodes in order */ |
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if (!node->done) |
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break; |
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list_del(&node->node); |
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first_add |= llist_add(&node->llist, &ctx->rsrc_put_llist); |
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} |
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spin_unlock_irqrestore(&ctx->rsrc_ref_lock, flags); |
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|
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if (first_add) |
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mod_delayed_work(system_wq, &ctx->rsrc_put_work, delay); |
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} |
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|
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static struct io_rsrc_node *io_rsrc_node_alloc(void) |
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{ |
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struct io_rsrc_node *ref_node; |
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|
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ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL); |
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if (!ref_node) |
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return NULL; |
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|
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if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero, |
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0, GFP_KERNEL)) { |
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kfree(ref_node); |
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return NULL; |
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} |
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INIT_LIST_HEAD(&ref_node->node); |
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INIT_LIST_HEAD(&ref_node->rsrc_list); |
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ref_node->done = false; |
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return ref_node; |
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} |
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|
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void io_rsrc_node_switch(struct io_ring_ctx *ctx, |
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struct io_rsrc_data *data_to_kill) |
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__must_hold(&ctx->uring_lock) |
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{ |
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WARN_ON_ONCE(!ctx->rsrc_backup_node); |
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WARN_ON_ONCE(data_to_kill && !ctx->rsrc_node); |
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io_rsrc_refs_drop(ctx); |
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|
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if (data_to_kill) { |
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struct io_rsrc_node *rsrc_node = ctx->rsrc_node; |
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|
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rsrc_node->rsrc_data = data_to_kill; |
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spin_lock_irq(&ctx->rsrc_ref_lock); |
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list_add_tail(&rsrc_node->node, &ctx->rsrc_ref_list); |
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spin_unlock_irq(&ctx->rsrc_ref_lock); |
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|
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atomic_inc(&data_to_kill->refs); |
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percpu_ref_kill(&rsrc_node->refs); |
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ctx->rsrc_node = NULL; |
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} |
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|
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if (!ctx->rsrc_node) { |
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ctx->rsrc_node = ctx->rsrc_backup_node; |
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ctx->rsrc_backup_node = NULL; |
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} |
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} |
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int io_rsrc_node_switch_start(struct io_ring_ctx *ctx) |
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{ |
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if (ctx->rsrc_backup_node) |
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return 0; |
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ctx->rsrc_backup_node = io_rsrc_node_alloc(); |
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return ctx->rsrc_backup_node ? 0 : -ENOMEM; |
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} |
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|
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__cold static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, |
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struct io_ring_ctx *ctx) |
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{ |
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int ret; |
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|
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/* As we may drop ->uring_lock, other task may have started quiesce */ |
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if (data->quiesce) |
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return -ENXIO; |
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|
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data->quiesce = true; |
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do { |
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ret = io_rsrc_node_switch_start(ctx); |
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if (ret) |
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break; |
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io_rsrc_node_switch(ctx, data); |
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|
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/* kill initial ref, already quiesced if zero */ |
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if (atomic_dec_and_test(&data->refs)) |
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break; |
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mutex_unlock(&ctx->uring_lock); |
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flush_delayed_work(&ctx->rsrc_put_work); |
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ret = wait_for_completion_interruptible(&data->done); |
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if (!ret) { |
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mutex_lock(&ctx->uring_lock); |
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if (atomic_read(&data->refs) > 0) { |
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/* |
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* it has been revived by another thread while |
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* we were unlocked |
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*/ |
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mutex_unlock(&ctx->uring_lock); |
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} else { |
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break; |
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} |
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} |
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|
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atomic_inc(&data->refs); |
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/* wait for all works potentially completing data->done */ |
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flush_delayed_work(&ctx->rsrc_put_work); |
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reinit_completion(&data->done); |
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|
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ret = io_run_task_work_sig(); |
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mutex_lock(&ctx->uring_lock); |
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} while (ret >= 0); |
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data->quiesce = false; |
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|
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return ret; |
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} |
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static void io_free_page_table(void **table, size_t size) |
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{ |
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unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); |
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|
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for (i = 0; i < nr_tables; i++) |
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kfree(table[i]); |
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kfree(table); |
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} |
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|
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static void io_rsrc_data_free(struct io_rsrc_data *data) |
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{ |
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size_t size = data->nr * sizeof(data->tags[0][0]); |
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|
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if (data->tags) |
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io_free_page_table((void **)data->tags, size); |
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kfree(data); |
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} |
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static __cold void **io_alloc_page_table(size_t size) |
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{ |
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unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); |
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size_t init_size = size; |
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void **table; |
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|
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table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL_ACCOUNT); |
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if (!table) |
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return NULL; |
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for (i = 0; i < nr_tables; i++) { |
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unsigned int this_size = min_t(size_t, size, PAGE_SIZE); |
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|
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table[i] = kzalloc(this_size, GFP_KERNEL_ACCOUNT); |
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if (!table[i]) { |
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io_free_page_table(table, init_size); |
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return NULL; |
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} |
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size -= this_size; |
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} |
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return table; |
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} |
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|
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__cold static int io_rsrc_data_alloc(struct io_ring_ctx *ctx, |
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rsrc_put_fn *do_put, u64 __user *utags, |
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unsigned nr, struct io_rsrc_data **pdata) |
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{ |
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struct io_rsrc_data *data; |
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int ret = -ENOMEM; |
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unsigned i; |
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|
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data = kzalloc(sizeof(*data), GFP_KERNEL); |
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if (!data) |
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return -ENOMEM; |
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data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0])); |
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if (!data->tags) { |
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kfree(data); |
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return -ENOMEM; |
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} |
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|
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data->nr = nr; |
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data->ctx = ctx; |
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data->do_put = do_put; |
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if (utags) { |
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ret = -EFAULT; |
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for (i = 0; i < nr; i++) { |
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u64 *tag_slot = io_get_tag_slot(data, i); |
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|
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if (copy_from_user(tag_slot, &utags[i], |
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sizeof(*tag_slot))) |
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goto fail; |
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} |
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} |
|
|
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atomic_set(&data->refs, 1); |
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init_completion(&data->done); |
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*pdata = data; |
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return 0; |
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fail: |
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io_rsrc_data_free(data); |
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return ret; |
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} |
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|
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static int __io_sqe_files_update(struct io_ring_ctx *ctx, |
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struct io_uring_rsrc_update2 *up, |
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unsigned nr_args) |
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{ |
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u64 __user *tags = u64_to_user_ptr(up->tags); |
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__s32 __user *fds = u64_to_user_ptr(up->data); |
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struct io_rsrc_data *data = ctx->file_data; |
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struct io_fixed_file *file_slot; |
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struct file *file; |
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int fd, i, err = 0; |
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unsigned int done; |
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bool needs_switch = false; |
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|
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if (!ctx->file_data) |
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return -ENXIO; |
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if (up->offset + nr_args > ctx->nr_user_files) |
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return -EINVAL; |
|
|
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for (done = 0; done < nr_args; done++) { |
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u64 tag = 0; |
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|
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if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) || |
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copy_from_user(&fd, &fds[done], sizeof(fd))) { |
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err = -EFAULT; |
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break; |
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} |
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if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) { |
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err = -EINVAL; |
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break; |
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} |
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if (fd == IORING_REGISTER_FILES_SKIP) |
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continue; |
|
|
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i = array_index_nospec(up->offset + done, ctx->nr_user_files); |
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file_slot = io_fixed_file_slot(&ctx->file_table, i); |
|
|
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if (file_slot->file_ptr) { |
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file = (struct file *)(file_slot->file_ptr & FFS_MASK); |
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err = io_queue_rsrc_removal(data, i, ctx->rsrc_node, file); |
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if (err) |
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break; |
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file_slot->file_ptr = 0; |
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io_file_bitmap_clear(&ctx->file_table, i); |
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needs_switch = true; |
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} |
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if (fd != -1) { |
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file = fget(fd); |
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if (!file) { |
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err = -EBADF; |
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break; |
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} |
|
/* |
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* Don't allow io_uring instances to be registered. If |
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* UNIX isn't enabled, then this causes a reference |
|
* cycle and this instance can never get freed. If UNIX |
|
* is enabled we'll handle it just fine, but there's |
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* still no point in allowing a ring fd as it doesn't |
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* support regular read/write anyway. |
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*/ |
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if (io_is_uring_fops(file)) { |
|
fput(file); |
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err = -EBADF; |
|
break; |
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} |
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err = io_scm_file_account(ctx, file); |
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if (err) { |
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fput(file); |
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break; |
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} |
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*io_get_tag_slot(data, i) = tag; |
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io_fixed_file_set(file_slot, file); |
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io_file_bitmap_set(&ctx->file_table, i); |
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} |
|
} |
|
|
|
if (needs_switch) |
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io_rsrc_node_switch(ctx, data); |
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return done ? done : err; |
|
} |
|
|
|
static int __io_sqe_buffers_update(struct io_ring_ctx *ctx, |
|
struct io_uring_rsrc_update2 *up, |
|
unsigned int nr_args) |
|
{ |
|
u64 __user *tags = u64_to_user_ptr(up->tags); |
|
struct iovec iov, __user *iovs = u64_to_user_ptr(up->data); |
|
struct page *last_hpage = NULL; |
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bool needs_switch = false; |
|
__u32 done; |
|
int i, err; |
|
|
|
if (!ctx->buf_data) |
|
return -ENXIO; |
|
if (up->offset + nr_args > ctx->nr_user_bufs) |
|
return -EINVAL; |
|
|
|
for (done = 0; done < nr_args; done++) { |
|
struct io_mapped_ubuf *imu; |
|
int offset = up->offset + done; |
|
u64 tag = 0; |
|
|
|
err = io_copy_iov(ctx, &iov, iovs, done); |
|
if (err) |
|
break; |
|
if (tags && copy_from_user(&tag, &tags[done], sizeof(tag))) { |
|
err = -EFAULT; |
|
break; |
|
} |
|
err = io_buffer_validate(&iov); |
|
if (err) |
|
break; |
|
if (!iov.iov_base && tag) { |
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err = -EINVAL; |
|
break; |
|
} |
|
err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage); |
|
if (err) |
|
break; |
|
|
|
i = array_index_nospec(offset, ctx->nr_user_bufs); |
|
if (ctx->user_bufs[i] != ctx->dummy_ubuf) { |
|
err = io_queue_rsrc_removal(ctx->buf_data, i, |
|
ctx->rsrc_node, ctx->user_bufs[i]); |
|
if (unlikely(err)) { |
|
io_buffer_unmap(ctx, &imu); |
|
break; |
|
} |
|
ctx->user_bufs[i] = ctx->dummy_ubuf; |
|
needs_switch = true; |
|
} |
|
|
|
ctx->user_bufs[i] = imu; |
|
*io_get_tag_slot(ctx->buf_data, offset) = tag; |
|
} |
|
|
|
if (needs_switch) |
|
io_rsrc_node_switch(ctx, ctx->buf_data); |
|
return done ? done : err; |
|
} |
|
|
|
static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type, |
|
struct io_uring_rsrc_update2 *up, |
|
unsigned nr_args) |
|
{ |
|
__u32 tmp; |
|
int err; |
|
|
|
if (check_add_overflow(up->offset, nr_args, &tmp)) |
|
return -EOVERFLOW; |
|
err = io_rsrc_node_switch_start(ctx); |
|
if (err) |
|
return err; |
|
|
|
switch (type) { |
|
case IORING_RSRC_FILE: |
|
return __io_sqe_files_update(ctx, up, nr_args); |
|
case IORING_RSRC_BUFFER: |
|
return __io_sqe_buffers_update(ctx, up, nr_args); |
|
} |
|
return -EINVAL; |
|
} |
|
|
|
int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg, |
|
unsigned nr_args) |
|
{ |
|
struct io_uring_rsrc_update2 up; |
|
|
|
if (!nr_args) |
|
return -EINVAL; |
|
memset(&up, 0, sizeof(up)); |
|
if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update))) |
|
return -EFAULT; |
|
if (up.resv || up.resv2) |
|
return -EINVAL; |
|
return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args); |
|
} |
|
|
|
int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg, |
|
unsigned size, unsigned type) |
|
{ |
|
struct io_uring_rsrc_update2 up; |
|
|
|
if (size != sizeof(up)) |
|
return -EINVAL; |
|
if (copy_from_user(&up, arg, sizeof(up))) |
|
return -EFAULT; |
|
if (!up.nr || up.resv || up.resv2) |
|
return -EINVAL; |
|
return __io_register_rsrc_update(ctx, type, &up, up.nr); |
|
} |
|
|
|
__cold int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg, |
|
unsigned int size, unsigned int type) |
|
{ |
|
struct io_uring_rsrc_register rr; |
|
|
|
/* keep it extendible */ |
|
if (size != sizeof(rr)) |
|
return -EINVAL; |
|
|
|
memset(&rr, 0, sizeof(rr)); |
|
if (copy_from_user(&rr, arg, size)) |
|
return -EFAULT; |
|
if (!rr.nr || rr.resv2) |
|
return -EINVAL; |
|
if (rr.flags & ~IORING_RSRC_REGISTER_SPARSE) |
|
return -EINVAL; |
|
|
|
switch (type) { |
|
case IORING_RSRC_FILE: |
|
if (rr.flags & IORING_RSRC_REGISTER_SPARSE && rr.data) |
|
break; |
|
return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data), |
|
rr.nr, u64_to_user_ptr(rr.tags)); |
|
case IORING_RSRC_BUFFER: |
|
if (rr.flags & IORING_RSRC_REGISTER_SPARSE && rr.data) |
|
break; |
|
return io_sqe_buffers_register(ctx, u64_to_user_ptr(rr.data), |
|
rr.nr, u64_to_user_ptr(rr.tags)); |
|
} |
|
return -EINVAL; |
|
} |
|
|
|
int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
|
{ |
|
struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
|
|
|
if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT))) |
|
return -EINVAL; |
|
if (sqe->rw_flags || sqe->splice_fd_in) |
|
return -EINVAL; |
|
|
|
up->offset = READ_ONCE(sqe->off); |
|
up->nr_args = READ_ONCE(sqe->len); |
|
if (!up->nr_args) |
|
return -EINVAL; |
|
up->arg = READ_ONCE(sqe->addr); |
|
return 0; |
|
} |
|
|
|
static int io_files_update_with_index_alloc(struct io_kiocb *req, |
|
unsigned int issue_flags) |
|
{ |
|
struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
|
__s32 __user *fds = u64_to_user_ptr(up->arg); |
|
unsigned int done; |
|
struct file *file; |
|
int ret, fd; |
|
|
|
if (!req->ctx->file_data) |
|
return -ENXIO; |
|
|
|
for (done = 0; done < up->nr_args; done++) { |
|
if (copy_from_user(&fd, &fds[done], sizeof(fd))) { |
|
ret = -EFAULT; |
|
break; |
|
} |
|
|
|
file = fget(fd); |
|
if (!file) { |
|
ret = -EBADF; |
|
break; |
|
} |
|
ret = io_fixed_fd_install(req, issue_flags, file, |
|
IORING_FILE_INDEX_ALLOC); |
|
if (ret < 0) |
|
break; |
|
if (copy_to_user(&fds[done], &ret, sizeof(ret))) { |
|
__io_close_fixed(req->ctx, issue_flags, ret); |
|
ret = -EFAULT; |
|
break; |
|
} |
|
} |
|
|
|
if (done) |
|
return done; |
|
return ret; |
|
} |
|
|
|
int io_files_update(struct io_kiocb *req, unsigned int issue_flags) |
|
{ |
|
struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
|
struct io_ring_ctx *ctx = req->ctx; |
|
struct io_uring_rsrc_update2 up2; |
|
int ret; |
|
|
|
up2.offset = up->offset; |
|
up2.data = up->arg; |
|
up2.nr = 0; |
|
up2.tags = 0; |
|
up2.resv = 0; |
|
up2.resv2 = 0; |
|
|
|
if (up->offset == IORING_FILE_INDEX_ALLOC) { |
|
ret = io_files_update_with_index_alloc(req, issue_flags); |
|
} else { |
|
io_ring_submit_lock(ctx, issue_flags); |
|
ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE, |
|
&up2, up->nr_args); |
|
io_ring_submit_unlock(ctx, issue_flags); |
|
} |
|
|
|
if (ret < 0) |
|
req_set_fail(req); |
|
io_req_set_res(req, ret, 0); |
|
return IOU_OK; |
|
} |
|
|
|
int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx, |
|
struct io_rsrc_node *node, void *rsrc) |
|
{ |
|
u64 *tag_slot = io_get_tag_slot(data, idx); |
|
struct io_rsrc_put *prsrc; |
|
|
|
prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL); |
|
if (!prsrc) |
|
return -ENOMEM; |
|
|
|
prsrc->tag = *tag_slot; |
|
*tag_slot = 0; |
|
prsrc->rsrc = rsrc; |
|
list_add(&prsrc->list, &node->rsrc_list); |
|
return 0; |
|
} |
|
|
|
void __io_sqe_files_unregister(struct io_ring_ctx *ctx) |
|
{ |
|
#if !defined(IO_URING_SCM_ALL) |
|
int i; |
|
|
|
for (i = 0; i < ctx->nr_user_files; i++) { |
|
struct file *file = io_file_from_index(&ctx->file_table, i); |
|
|
|
if (!file) |
|
continue; |
|
if (io_fixed_file_slot(&ctx->file_table, i)->file_ptr & FFS_SCM) |
|
continue; |
|
io_file_bitmap_clear(&ctx->file_table, i); |
|
fput(file); |
|
} |
|
#endif |
|
|
|
#if defined(CONFIG_UNIX) |
|
if (ctx->ring_sock) { |
|
struct sock *sock = ctx->ring_sock->sk; |
|
struct sk_buff *skb; |
|
|
|
while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL) |
|
kfree_skb(skb); |
|
} |
|
#endif |
|
io_free_file_tables(&ctx->file_table); |
|
io_rsrc_data_free(ctx->file_data); |
|
ctx->file_data = NULL; |
|
ctx->nr_user_files = 0; |
|
} |
|
|
|
int io_sqe_files_unregister(struct io_ring_ctx *ctx) |
|
{ |
|
unsigned nr = ctx->nr_user_files; |
|
int ret; |
|
|
|
if (!ctx->file_data) |
|
return -ENXIO; |
|
|
|
/* |
|
* Quiesce may unlock ->uring_lock, and while it's not held |
|
* prevent new requests using the table. |
|
*/ |
|
ctx->nr_user_files = 0; |
|
ret = io_rsrc_ref_quiesce(ctx->file_data, ctx); |
|
ctx->nr_user_files = nr; |
|
if (!ret) |
|
__io_sqe_files_unregister(ctx); |
|
return ret; |
|
} |
|
|
|
/* |
|
* Ensure the UNIX gc is aware of our file set, so we are certain that |
|
* the io_uring can be safely unregistered on process exit, even if we have |
|
* loops in the file referencing. We account only files that can hold other |
|
* files because otherwise they can't form a loop and so are not interesting |
|
* for GC. |
|
*/ |
|
int __io_scm_file_account(struct io_ring_ctx *ctx, struct file *file) |
|
{ |
|
#if defined(CONFIG_UNIX) |
|
struct sock *sk = ctx->ring_sock->sk; |
|
struct sk_buff_head *head = &sk->sk_receive_queue; |
|
struct scm_fp_list *fpl; |
|
struct sk_buff *skb; |
|
|
|
if (likely(!io_file_need_scm(file))) |
|
return 0; |
|
|
|
/* |
|
* See if we can merge this file into an existing skb SCM_RIGHTS |
|
* file set. If there's no room, fall back to allocating a new skb |
|
* and filling it in. |
|
*/ |
|
spin_lock_irq(&head->lock); |
|
skb = skb_peek(head); |
|
if (skb && UNIXCB(skb).fp->count < SCM_MAX_FD) |
|
__skb_unlink(skb, head); |
|
else |
|
skb = NULL; |
|
spin_unlock_irq(&head->lock); |
|
|
|
if (!skb) { |
|
fpl = kzalloc(sizeof(*fpl), GFP_KERNEL); |
|
if (!fpl) |
|
return -ENOMEM; |
|
|
|
skb = alloc_skb(0, GFP_KERNEL); |
|
if (!skb) { |
|
kfree(fpl); |
|
return -ENOMEM; |
|
} |
|
|
|
fpl->user = get_uid(current_user()); |
|
fpl->max = SCM_MAX_FD; |
|
fpl->count = 0; |
|
|
|
UNIXCB(skb).fp = fpl; |
|
skb->sk = sk; |
|
skb->destructor = unix_destruct_scm; |
|
refcount_add(skb->truesize, &sk->sk_wmem_alloc); |
|
} |
|
|
|
fpl = UNIXCB(skb).fp; |
|
fpl->fp[fpl->count++] = get_file(file); |
|
unix_inflight(fpl->user, file); |
|
skb_queue_head(head, skb); |
|
fput(file); |
|
#endif |
|
return 0; |
|
} |
|
|
|
static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc) |
|
{ |
|
struct file *file = prsrc->file; |
|
#if defined(CONFIG_UNIX) |
|
struct sock *sock = ctx->ring_sock->sk; |
|
struct sk_buff_head list, *head = &sock->sk_receive_queue; |
|
struct sk_buff *skb; |
|
int i; |
|
|
|
if (!io_file_need_scm(file)) { |
|
fput(file); |
|
return; |
|
} |
|
|
|
__skb_queue_head_init(&list); |
|
|
|
/* |
|
* Find the skb that holds this file in its SCM_RIGHTS. When found, |
|
* remove this entry and rearrange the file array. |
|
*/ |
|
skb = skb_dequeue(head); |
|
while (skb) { |
|
struct scm_fp_list *fp; |
|
|
|
fp = UNIXCB(skb).fp; |
|
for (i = 0; i < fp->count; i++) { |
|
int left; |
|
|
|
if (fp->fp[i] != file) |
|
continue; |
|
|
|
unix_notinflight(fp->user, fp->fp[i]); |
|
left = fp->count - 1 - i; |
|
if (left) { |
|
memmove(&fp->fp[i], &fp->fp[i + 1], |
|
left * sizeof(struct file *)); |
|
} |
|
fp->count--; |
|
if (!fp->count) { |
|
kfree_skb(skb); |
|
skb = NULL; |
|
} else { |
|
__skb_queue_tail(&list, skb); |
|
} |
|
fput(file); |
|
file = NULL; |
|
break; |
|
} |
|
|
|
if (!file) |
|
break; |
|
|
|
__skb_queue_tail(&list, skb); |
|
|
|
skb = skb_dequeue(head); |
|
} |
|
|
|
if (skb_peek(&list)) { |
|
spin_lock_irq(&head->lock); |
|
while ((skb = __skb_dequeue(&list)) != NULL) |
|
__skb_queue_tail(head, skb); |
|
spin_unlock_irq(&head->lock); |
|
} |
|
#else |
|
fput(file); |
|
#endif |
|
} |
|
|
|
int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, |
|
unsigned nr_args, u64 __user *tags) |
|
{ |
|
__s32 __user *fds = (__s32 __user *) arg; |
|
struct file *file; |
|
int fd, ret; |
|
unsigned i; |
|
|
|
if (ctx->file_data) |
|
return -EBUSY; |
|
if (!nr_args) |
|
return -EINVAL; |
|
if (nr_args > IORING_MAX_FIXED_FILES) |
|
return -EMFILE; |
|
if (nr_args > rlimit(RLIMIT_NOFILE)) |
|
return -EMFILE; |
|
ret = io_rsrc_node_switch_start(ctx); |
|
if (ret) |
|
return ret; |
|
ret = io_rsrc_data_alloc(ctx, io_rsrc_file_put, tags, nr_args, |
|
&ctx->file_data); |
|
if (ret) |
|
return ret; |
|
|
|
if (!io_alloc_file_tables(&ctx->file_table, nr_args)) { |
|
io_rsrc_data_free(ctx->file_data); |
|
ctx->file_data = NULL; |
|
return -ENOMEM; |
|
} |
|
|
|
for (i = 0; i < nr_args; i++, ctx->nr_user_files++) { |
|
struct io_fixed_file *file_slot; |
|
|
|
if (fds && copy_from_user(&fd, &fds[i], sizeof(fd))) { |
|
ret = -EFAULT; |
|
goto fail; |
|
} |
|
/* allow sparse sets */ |
|
if (!fds || fd == -1) { |
|
ret = -EINVAL; |
|
if (unlikely(*io_get_tag_slot(ctx->file_data, i))) |
|
goto fail; |
|
continue; |
|
} |
|
|
|
file = fget(fd); |
|
ret = -EBADF; |
|
if (unlikely(!file)) |
|
goto fail; |
|
|
|
/* |
|
* Don't allow io_uring instances to be registered. If UNIX |
|
* isn't enabled, then this causes a reference cycle and this |
|
* instance can never get freed. If UNIX is enabled we'll |
|
* handle it just fine, but there's still no point in allowing |
|
* a ring fd as it doesn't support regular read/write anyway. |
|
*/ |
|
if (io_is_uring_fops(file)) { |
|
fput(file); |
|
goto fail; |
|
} |
|
ret = io_scm_file_account(ctx, file); |
|
if (ret) { |
|
fput(file); |
|
goto fail; |
|
} |
|
file_slot = io_fixed_file_slot(&ctx->file_table, i); |
|
io_fixed_file_set(file_slot, file); |
|
io_file_bitmap_set(&ctx->file_table, i); |
|
} |
|
|
|
/* default it to the whole table */ |
|
io_file_table_set_alloc_range(ctx, 0, ctx->nr_user_files); |
|
io_rsrc_node_switch(ctx, NULL); |
|
return 0; |
|
fail: |
|
__io_sqe_files_unregister(ctx); |
|
return ret; |
|
} |
|
|
|
static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc) |
|
{ |
|
io_buffer_unmap(ctx, &prsrc->buf); |
|
prsrc->buf = NULL; |
|
} |
|
|
|
void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx) |
|
{ |
|
unsigned int i; |
|
|
|
for (i = 0; i < ctx->nr_user_bufs; i++) |
|
io_buffer_unmap(ctx, &ctx->user_bufs[i]); |
|
kfree(ctx->user_bufs); |
|
io_rsrc_data_free(ctx->buf_data); |
|
ctx->user_bufs = NULL; |
|
ctx->buf_data = NULL; |
|
ctx->nr_user_bufs = 0; |
|
} |
|
|
|
int io_sqe_buffers_unregister(struct io_ring_ctx *ctx) |
|
{ |
|
unsigned nr = ctx->nr_user_bufs; |
|
int ret; |
|
|
|
if (!ctx->buf_data) |
|
return -ENXIO; |
|
|
|
/* |
|
* Quiesce may unlock ->uring_lock, and while it's not held |
|
* prevent new requests using the table. |
|
*/ |
|
ctx->nr_user_bufs = 0; |
|
ret = io_rsrc_ref_quiesce(ctx->buf_data, ctx); |
|
ctx->nr_user_bufs = nr; |
|
if (!ret) |
|
__io_sqe_buffers_unregister(ctx); |
|
return ret; |
|
} |
|
|
|
/* |
|
* Not super efficient, but this is just a registration time. And we do cache |
|
* the last compound head, so generally we'll only do a full search if we don't |
|
* match that one. |
|
* |
|
* We check if the given compound head page has already been accounted, to |
|
* avoid double accounting it. This allows us to account the full size of the |
|
* page, not just the constituent pages of a huge page. |
|
*/ |
|
static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages, |
|
int nr_pages, struct page *hpage) |
|
{ |
|
int i, j; |
|
|
|
/* check current page array */ |
|
for (i = 0; i < nr_pages; i++) { |
|
if (!PageCompound(pages[i])) |
|
continue; |
|
if (compound_head(pages[i]) == hpage) |
|
return true; |
|
} |
|
|
|
/* check previously registered pages */ |
|
for (i = 0; i < ctx->nr_user_bufs; i++) { |
|
struct io_mapped_ubuf *imu = ctx->user_bufs[i]; |
|
|
|
for (j = 0; j < imu->nr_bvecs; j++) { |
|
if (!PageCompound(imu->bvec[j].bv_page)) |
|
continue; |
|
if (compound_head(imu->bvec[j].bv_page) == hpage) |
|
return true; |
|
} |
|
} |
|
|
|
return false; |
|
} |
|
|
|
static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages, |
|
int nr_pages, struct io_mapped_ubuf *imu, |
|
struct page **last_hpage) |
|
{ |
|
int i, ret; |
|
|
|
imu->acct_pages = 0; |
|
for (i = 0; i < nr_pages; i++) { |
|
if (!PageCompound(pages[i])) { |
|
imu->acct_pages++; |
|
} else { |
|
struct page *hpage; |
|
|
|
hpage = compound_head(pages[i]); |
|
if (hpage == *last_hpage) |
|
continue; |
|
*last_hpage = hpage; |
|
if (headpage_already_acct(ctx, pages, i, hpage)) |
|
continue; |
|
imu->acct_pages += page_size(hpage) >> PAGE_SHIFT; |
|
} |
|
} |
|
|
|
if (!imu->acct_pages) |
|
return 0; |
|
|
|
ret = io_account_mem(ctx, imu->acct_pages); |
|
if (ret) |
|
imu->acct_pages = 0; |
|
return ret; |
|
} |
|
|
|
struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages) |
|
{ |
|
unsigned long start, end, nr_pages; |
|
struct vm_area_struct **vmas = NULL; |
|
struct page **pages = NULL; |
|
int i, pret, ret = -ENOMEM; |
|
|
|
end = (ubuf + len + PAGE_SIZE - 1) >> PAGE_SHIFT; |
|
start = ubuf >> PAGE_SHIFT; |
|
nr_pages = end - start; |
|
|
|
pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL); |
|
if (!pages) |
|
goto done; |
|
|
|
vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *), |
|
GFP_KERNEL); |
|
if (!vmas) |
|
goto done; |
|
|
|
ret = 0; |
|
mmap_read_lock(current->mm); |
|
pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM, |
|
pages, vmas); |
|
if (pret == nr_pages) { |
|
/* don't support file backed memory */ |
|
for (i = 0; i < nr_pages; i++) { |
|
struct vm_area_struct *vma = vmas[i]; |
|
|
|
if (vma_is_shmem(vma)) |
|
continue; |
|
if (vma->vm_file && |
|
!is_file_hugepages(vma->vm_file)) { |
|
ret = -EOPNOTSUPP; |
|
break; |
|
} |
|
} |
|
*npages = nr_pages; |
|
} else { |
|
ret = pret < 0 ? pret : -EFAULT; |
|
} |
|
mmap_read_unlock(current->mm); |
|
if (ret) { |
|
/* |
|
* if we did partial map, or found file backed vmas, |
|
* release any pages we did get |
|
*/ |
|
if (pret > 0) |
|
unpin_user_pages(pages, pret); |
|
goto done; |
|
} |
|
ret = 0; |
|
done: |
|
kvfree(vmas); |
|
if (ret < 0) { |
|
kvfree(pages); |
|
pages = ERR_PTR(ret); |
|
} |
|
return pages; |
|
} |
|
|
|
static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, |
|
struct io_mapped_ubuf **pimu, |
|
struct page **last_hpage) |
|
{ |
|
struct io_mapped_ubuf *imu = NULL; |
|
struct page **pages = NULL; |
|
unsigned long off; |
|
size_t size; |
|
int ret, nr_pages, i; |
|
|
|
*pimu = ctx->dummy_ubuf; |
|
if (!iov->iov_base) |
|
return 0; |
|
|
|
ret = -ENOMEM; |
|
pages = io_pin_pages((unsigned long) iov->iov_base, iov->iov_len, |
|
&nr_pages); |
|
if (IS_ERR(pages)) { |
|
ret = PTR_ERR(pages); |
|
pages = NULL; |
|
goto done; |
|
} |
|
|
|
imu = kvmalloc(struct_size(imu, bvec, nr_pages), GFP_KERNEL); |
|
if (!imu) |
|
goto done; |
|
|
|
ret = io_buffer_account_pin(ctx, pages, nr_pages, imu, last_hpage); |
|
if (ret) { |
|
unpin_user_pages(pages, nr_pages); |
|
goto done; |
|
} |
|
|
|
off = (unsigned long) iov->iov_base & ~PAGE_MASK; |
|
size = iov->iov_len; |
|
for (i = 0; i < nr_pages; i++) { |
|
size_t vec_len; |
|
|
|
vec_len = min_t(size_t, size, PAGE_SIZE - off); |
|
imu->bvec[i].bv_page = pages[i]; |
|
imu->bvec[i].bv_len = vec_len; |
|
imu->bvec[i].bv_offset = off; |
|
off = 0; |
|
size -= vec_len; |
|
} |
|
/* store original address for later verification */ |
|
imu->ubuf = (unsigned long) iov->iov_base; |
|
imu->ubuf_end = imu->ubuf + iov->iov_len; |
|
imu->nr_bvecs = nr_pages; |
|
*pimu = imu; |
|
ret = 0; |
|
done: |
|
if (ret) |
|
kvfree(imu); |
|
kvfree(pages); |
|
return ret; |
|
} |
|
|
|
static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args) |
|
{ |
|
ctx->user_bufs = kcalloc(nr_args, sizeof(*ctx->user_bufs), GFP_KERNEL); |
|
return ctx->user_bufs ? 0 : -ENOMEM; |
|
} |
|
|
|
int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg, |
|
unsigned int nr_args, u64 __user *tags) |
|
{ |
|
struct page *last_hpage = NULL; |
|
struct io_rsrc_data *data; |
|
int i, ret; |
|
struct iovec iov; |
|
|
|
BUILD_BUG_ON(IORING_MAX_REG_BUFFERS >= (1u << 16)); |
|
|
|
if (ctx->user_bufs) |
|
return -EBUSY; |
|
if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS) |
|
return -EINVAL; |
|
ret = io_rsrc_node_switch_start(ctx); |
|
if (ret) |
|
return ret; |
|
ret = io_rsrc_data_alloc(ctx, io_rsrc_buf_put, tags, nr_args, &data); |
|
if (ret) |
|
return ret; |
|
ret = io_buffers_map_alloc(ctx, nr_args); |
|
if (ret) { |
|
io_rsrc_data_free(data); |
|
return ret; |
|
} |
|
|
|
for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) { |
|
if (arg) { |
|
ret = io_copy_iov(ctx, &iov, arg, i); |
|
if (ret) |
|
break; |
|
ret = io_buffer_validate(&iov); |
|
if (ret) |
|
break; |
|
} else { |
|
memset(&iov, 0, sizeof(iov)); |
|
} |
|
|
|
if (!iov.iov_base && *io_get_tag_slot(data, i)) { |
|
ret = -EINVAL; |
|
break; |
|
} |
|
|
|
ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i], |
|
&last_hpage); |
|
if (ret) |
|
break; |
|
} |
|
|
|
WARN_ON_ONCE(ctx->buf_data); |
|
|
|
ctx->buf_data = data; |
|
if (ret) |
|
__io_sqe_buffers_unregister(ctx); |
|
else |
|
io_rsrc_node_switch(ctx, NULL); |
|
return ret; |
|
} |
|
|
|
int io_import_fixed(int ddir, struct iov_iter *iter, |
|
struct io_mapped_ubuf *imu, |
|
u64 buf_addr, size_t len) |
|
{ |
|
u64 buf_end; |
|
size_t offset; |
|
|
|
if (WARN_ON_ONCE(!imu)) |
|
return -EFAULT; |
|
if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end))) |
|
return -EFAULT; |
|
/* not inside the mapped region */ |
|
if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end)) |
|
return -EFAULT; |
|
|
|
/* |
|
* May not be a start of buffer, set size appropriately |
|
* and advance us to the beginning. |
|
*/ |
|
offset = buf_addr - imu->ubuf; |
|
iov_iter_bvec(iter, ddir, imu->bvec, imu->nr_bvecs, offset + len); |
|
|
|
if (offset) { |
|
/* |
|
* Don't use iov_iter_advance() here, as it's really slow for |
|
* using the latter parts of a big fixed buffer - it iterates |
|
* over each segment manually. We can cheat a bit here, because |
|
* we know that: |
|
* |
|
* 1) it's a BVEC iter, we set it up |
|
* 2) all bvecs are PAGE_SIZE in size, except potentially the |
|
* first and last bvec |
|
* |
|
* So just find our index, and adjust the iterator afterwards. |
|
* If the offset is within the first bvec (or the whole first |
|
* bvec, just use iov_iter_advance(). This makes it easier |
|
* since we can just skip the first segment, which may not |
|
* be PAGE_SIZE aligned. |
|
*/ |
|
const struct bio_vec *bvec = imu->bvec; |
|
|
|
if (offset <= bvec->bv_len) { |
|
iov_iter_advance(iter, offset); |
|
} else { |
|
unsigned long seg_skip; |
|
|
|
/* skip first vec */ |
|
offset -= bvec->bv_len; |
|
seg_skip = 1 + (offset >> PAGE_SHIFT); |
|
|
|
iter->bvec = bvec + seg_skip; |
|
iter->nr_segs -= seg_skip; |
|
iter->count -= bvec->bv_len + offset; |
|
iter->iov_offset = offset & ~PAGE_MASK; |
|
} |
|
} |
|
|
|
return 0; |
|
}
|
|
|