diff options
Diffstat (limited to 'io_uring/io_uring.c')
| -rw-r--r-- | io_uring/io_uring.c | 1414 |
1 files changed, 2 insertions, 1412 deletions
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index e395167999ed..0c47c919887f 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -68,7 +68,6 @@ #include <linux/uaccess.h> #include <linux/nospec.h> #include <linux/sizes.h> -#include <linux/hugetlb.h> #include <linux/highmem.h> #include <linux/fsnotify.h> #include <linux/fadvise.h> @@ -94,6 +93,7 @@ #include "sqpoll.h" #include "fdinfo.h" #include "kbuf.h" +#include "rsrc.h" #include "xattr.h" #include "nop.h" @@ -114,17 +114,9 @@ #define IORING_MAX_ENTRIES 32768 #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES) -/* only define max */ -#define IORING_MAX_FIXED_FILES (1U << 20) #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \ IORING_REGISTER_LAST + IORING_OP_LAST) -#define IO_RSRC_TAG_TABLE_SHIFT (PAGE_SHIFT - 3) -#define IO_RSRC_TAG_TABLE_MAX (1U << IO_RSRC_TAG_TABLE_SHIFT) -#define IO_RSRC_TAG_TABLE_MASK (IO_RSRC_TAG_TABLE_MAX - 1) - -#define IORING_MAX_REG_BUFFERS (1U << 14) - #define SQE_COMMON_FLAGS (IOSQE_FIXED_FILE | IOSQE_IO_LINK | \ IOSQE_IO_HARDLINK | IOSQE_ASYNC) @@ -140,38 +132,6 @@ #define IO_TCTX_REFS_CACHE_NR (1U << 10) -struct io_rsrc_put { - struct list_head list; - u64 tag; - union { - void *rsrc; - struct file *file; - struct io_mapped_ubuf *buf; - }; -}; - -struct io_rsrc_node { - struct percpu_ref refs; - struct list_head node; - struct list_head rsrc_list; - struct io_rsrc_data *rsrc_data; - struct llist_node llist; - bool done; -}; - -typedef void (rsrc_put_fn)(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc); - -struct io_rsrc_data { - struct io_ring_ctx *ctx; - - u64 **tags; - unsigned int nr; - rsrc_put_fn *do_put; - atomic_t refs; - struct completion done; - bool quiesce; -}; - #define IO_COMPL_BATCH 32 #define IO_REQ_CACHE_SIZE 32 #define IO_REQ_ALLOC_BATCH 8 @@ -188,13 +148,6 @@ struct io_rw { rwf_t flags; }; -struct io_rsrc_update { - struct file *file; - u64 arg; - u32 nr_args; - u32 offset; -}; - struct io_rw_state { struct iov_iter iter; struct iov_iter_state iter_state; @@ -209,11 +162,6 @@ struct io_async_rw { }; enum { - IORING_RSRC_FILE = 0, - IORING_RSRC_BUFFER = 1, -}; - -enum { IO_CHECK_CQ_OVERFLOW_BIT, IO_CHECK_CQ_DROPPED_BIT, }; @@ -233,12 +181,8 @@ static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx, bool cancel_all); static void io_dismantle_req(struct io_kiocb *req); -static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type, - struct io_uring_rsrc_update2 *up, - unsigned nr_args); static void io_clean_op(struct io_kiocb *req); static void io_queue_sqe(struct io_kiocb *req); -static void io_rsrc_put_work(struct work_struct *work); static void io_req_task_queue(struct io_kiocb *req); static void __io_submit_flush_completions(struct io_ring_ctx *ctx); @@ -268,22 +212,6 @@ struct sock *io_uring_get_socket(struct file *file) } EXPORT_SYMBOL(io_uring_get_socket); -#if defined(CONFIG_UNIX) -static inline bool io_file_need_scm(struct file *filp) -{ -#if defined(IO_URING_SCM_ALL) - return true; -#else - return !!unix_get_socket(filp); -#endif -} -#else -static inline bool io_file_need_scm(struct file *filp) -{ - return false; -} -#endif - static inline void io_tw_lock(struct io_ring_ctx *ctx, bool *locked) { if (!*locked) { @@ -298,67 +226,6 @@ static inline void io_submit_flush_completions(struct io_ring_ctx *ctx) __io_submit_flush_completions(ctx); } -#define IO_RSRC_REF_BATCH 100 - -static void io_rsrc_put_node(struct io_rsrc_node *node, int nr) -{ - percpu_ref_put_many(&node->refs, nr); -} - -static inline void io_req_put_rsrc_locked(struct io_kiocb *req, - struct io_ring_ctx *ctx) - __must_hold(&ctx->uring_lock) -{ - struct io_rsrc_node *node = req->rsrc_node; - - if (node) { - if (node == ctx->rsrc_node) - ctx->rsrc_cached_refs++; - else - io_rsrc_put_node(node, 1); - } -} - -static inline void io_req_put_rsrc(struct io_kiocb *req) -{ - if (req->rsrc_node) - io_rsrc_put_node(req->rsrc_node, 1); -} - -static __cold void io_rsrc_refs_drop(struct io_ring_ctx *ctx) - __must_hold(&ctx->uring_lock) -{ - if (ctx->rsrc_cached_refs) { - io_rsrc_put_node(ctx->rsrc_node, ctx->rsrc_cached_refs); - ctx->rsrc_cached_refs = 0; - } -} - -static void io_rsrc_refs_refill(struct io_ring_ctx *ctx) - __must_hold(&ctx->uring_lock) -{ - ctx->rsrc_cached_refs += IO_RSRC_REF_BATCH; - percpu_ref_get_many(&ctx->rsrc_node->refs, IO_RSRC_REF_BATCH); -} - -static inline void io_req_set_rsrc_node(struct io_kiocb *req, - struct io_ring_ctx *ctx, - unsigned int issue_flags) -{ - if (!req->rsrc_node) { - req->rsrc_node = ctx->rsrc_node; - - if (!(issue_flags & IO_URING_F_UNLOCKED)) { - lockdep_assert_held(&ctx->uring_lock); - ctx->rsrc_cached_refs--; - if (unlikely(ctx->rsrc_cached_refs < 0)) - io_rsrc_refs_refill(ctx); - } else { - percpu_ref_get(&req->rsrc_node->refs); - } - } -} - static bool io_match_linked(struct io_kiocb *head) { struct io_kiocb *req; @@ -2870,92 +2737,6 @@ static __maybe_unused int io_eopnotsupp_prep(struct io_kiocb *kiocb, return -EOPNOTSUPP; } -static 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); - - 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); - __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, issue_flags, ret); - ret = -EFAULT; - break; - } - } - - if (done) - return done; - return ret; -} - -static int io_files_update(struct io_kiocb *req, unsigned int issue_flags) -{ - struct io_rsrc_update *up = io_kiocb_to_cmd(req); - 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; -} - static int io_req_prep_async(struct io_kiocb *req) { const struct io_op_def *def = &io_op_defs[req->opcode]; @@ -3696,7 +3477,7 @@ static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode, return -1; } -static int io_run_task_work_sig(void) +int io_run_task_work_sig(void) { if (io_run_task_work()) return 1; @@ -3798,560 +3579,6 @@ 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_free_page_table(void **table, size_t size) -{ - unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); - - for (i = 0; i < nr_tables; i++) - kfree(table[i]); - kfree(table); -} - -static __cold void **io_alloc_page_table(size_t size) -{ - unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); - size_t init_size = size; - void **table; - - table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL_ACCOUNT); - if (!table) - return NULL; - - for (i = 0; i < nr_tables; i++) { - unsigned int this_size = min_t(size_t, size, PAGE_SIZE); - - table[i] = kzalloc(this_size, GFP_KERNEL_ACCOUNT); - if (!table[i]) { - io_free_page_table(table, init_size); - return NULL; - } - size -= this_size; - } - return table; -} - -static void io_rsrc_node_destroy(struct io_rsrc_node *ref_node) -{ - percpu_ref_exit(&ref_node->refs); - kfree(ref_node); -} - -static __cold void io_rsrc_node_ref_zero(struct percpu_ref *ref) -{ - struct io_rsrc_node *node = container_of(ref, struct io_rsrc_node, refs); - struct io_ring_ctx *ctx = node->rsrc_data->ctx; - unsigned long flags; - bool first_add = false; - unsigned long delay = HZ; - - spin_lock_irqsave(&ctx->rsrc_ref_lock, flags); - node->done = true; - - /* if we are mid-quiesce then do not delay */ - if (node->rsrc_data->quiesce) - delay = 0; - - while (!list_empty(&ctx->rsrc_ref_list)) { - node = list_first_entry(&ctx->rsrc_ref_list, - struct io_rsrc_node, node); - /* recycle ref nodes in order */ - if (!node->done) - break; - list_del(&node->node); - first_add |= llist_add(&node->llist, &ctx->rsrc_put_llist); - } - spin_unlock_irqrestore(&ctx->rsrc_ref_lock, flags); - - if (first_add) - mod_delayed_work(system_wq, &ctx->rsrc_put_work, delay); -} - -static struct io_rsrc_node *io_rsrc_node_alloc(void) -{ - struct io_rsrc_node *ref_node; - - ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL); - if (!ref_node) - return NULL; - - if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero, - 0, GFP_KERNEL)) { - kfree(ref_node); - return NULL; - } - INIT_LIST_HEAD(&ref_node->node); - INIT_LIST_HEAD(&ref_node->rsrc_list); - ref_node->done = false; - return ref_node; -} - -void io_rsrc_node_switch(struct io_ring_ctx *ctx, - struct io_rsrc_data *data_to_kill) - __must_hold(&ctx->uring_lock) -{ - WARN_ON_ONCE(!ctx->rsrc_backup_node); - WARN_ON_ONCE(data_to_kill && !ctx->rsrc_node); - - io_rsrc_refs_drop(ctx); - - if (data_to_kill) { - struct io_rsrc_node *rsrc_node = ctx->rsrc_node; - - rsrc_node->rsrc_data = data_to_kill; - spin_lock_irq(&ctx->rsrc_ref_lock); - list_add_tail(&rsrc_node->node, &ctx->rsrc_ref_list); - spin_unlock_irq(&ctx->rsrc_ref_lock); - - atomic_inc(&data_to_kill->refs); - percpu_ref_kill(&rsrc_node->refs); - ctx->rsrc_node = NULL; - } - - if (!ctx->rsrc_node) { - ctx->rsrc_node = ctx->rsrc_backup_node; - ctx->rsrc_backup_node = NULL; - } -} - -int io_rsrc_node_switch_start(struct io_ring_ctx *ctx) -{ - if (ctx->rsrc_backup_node) - return 0; - ctx->rsrc_backup_node = io_rsrc_node_alloc(); - return ctx->rsrc_backup_node ? 0 : -ENOMEM; -} - -static __cold int io_rsrc_ref_quiesce(struct io_rsrc_data *data, - struct io_ring_ctx *ctx) -{ - int ret; - - /* As we may drop ->uring_lock, other task may have started quiesce */ - if (data->quiesce) - return -ENXIO; - - data->quiesce = true; - do { - ret = io_rsrc_node_switch_start(ctx); - if (ret) - break; - io_rsrc_node_switch(ctx, data); - - /* kill initial ref, already quiesced if zero */ - if (atomic_dec_and_test(&data->refs)) - break; - mutex_unlock(&ctx->uring_lock); - flush_delayed_work(&ctx->rsrc_put_work); - ret = wait_for_completion_interruptible(&data->done); - if (!ret) { - mutex_lock(&ctx->uring_lock); - if (atomic_read(&data->refs) > 0) { - /* - * it has been revived by another thread while - * we were unlocked - */ - mutex_unlock(&ctx->uring_lock); - } else { - break; - } - } - - atomic_inc(&data->refs); - /* wait for all works potentially completing data->done */ - flush_delayed_work(&ctx->rsrc_put_work); - reinit_completion(&data->done); - - ret = io_run_task_work_sig(); - mutex_lock(&ctx->uring_lock); - } while (ret >= 0); - data->quiesce = false; - - return ret; -} - -static u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx) -{ - unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK; - unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT; - - return &data->tags[table_idx][off]; -} - -static void io_rsrc_data_free(struct io_rsrc_data *data) -{ - size_t size = data->nr * sizeof(data->tags[0][0]); - - if (data->tags) - io_free_page_table((void **)data->tags, size); - kfree(data); -} - -static __cold int io_rsrc_data_alloc(struct io_ring_ctx *ctx, rsrc_put_fn *do_put, - u64 __user *utags, unsigned nr, - struct io_rsrc_data **pdata) -{ - struct io_rsrc_data *data; - int ret = -ENOMEM; - unsigned i; - - data = kzalloc(sizeof(*data), GFP_KERNEL); - if (!data) - return -ENOMEM; - data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0])); - if (!data->tags) { - kfree(data); - return -ENOMEM; - } - - data->nr = nr; - data->ctx = ctx; - data->do_put = do_put; - if (utags) { - ret = -EFAULT; - for (i = 0; i < nr; i++) { - u64 *tag_slot = io_get_tag_slot(data, i); - - if (copy_from_user(tag_slot, &utags[i], - sizeof(*tag_slot))) - goto fail; - } - } - - atomic_set(&data->refs, 1); - init_completion(&data->done); - *pdata = data; - return 0; -fail: - io_rsrc_data_free(data); - return ret; -} - -static 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; -} - -static 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. - */ -static 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 -} - -static void __io_rsrc_put_work(struct io_rsrc_node *ref_node) -{ - struct io_rsrc_data *rsrc_data = ref_node->rsrc_data; - struct io_ring_ctx *ctx = rsrc_data->ctx; - struct io_rsrc_put *prsrc, *tmp; - - list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) { - list_del(&prsrc->list); - - if (prsrc->tag) { - if (ctx->flags & IORING_SETUP_IOPOLL) - mutex_lock(&ctx->uring_lock); - - spin_lock(&ctx->completion_lock); - io_fill_cqe_aux(ctx, prsrc->tag, 0, 0); - io_commit_cqring(ctx); - spin_unlock(&ctx->completion_lock); - io_cqring_ev_posted(ctx); - - if (ctx->flags & IORING_SETUP_IOPOLL) - mutex_unlock(&ctx->uring_lock); - } - - rsrc_data->do_put(ctx, prsrc); - kfree(prsrc); - } - - io_rsrc_node_destroy(ref_node); - if (atomic_dec_and_test(&rsrc_data->refs)) - complete(&rsrc_data->done); -} - -static void io_rsrc_put_work(struct work_struct *work) -{ - struct io_ring_ctx *ctx; - struct llist_node *node; - - ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work); - node = llist_del_all(&ctx->rsrc_put_llist); - - while (node) { - struct io_rsrc_node *ref_node; - struct llist_node *next = node->next; - - ref_node = llist_entry(node, struct io_rsrc_node, llist); - __io_rsrc_put_work(ref_node); - node = next; - } -} - -static 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); - } - - io_rsrc_node_switch(ctx, NULL); - return 0; -fail: - __io_sqe_files_unregister(ctx); - return ret; -} - -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; -} - int io_install_fixed_file(struct io_kiocb *req, struct file *file, unsigned int issue_flags, u32 slot_index) __must_hold(&req->ctx->uring_lock) @@ -4402,136 +3629,6 @@ err: return ret; } -static int __io_sqe_files_update(struct io_ring_ctx *ctx, - struct io_uring_rsrc_update2 *up, - unsigned nr_args) -{ - u64 __user *tags = u64_to_user_ptr(up->tags); - __s32 __user *fds = u64_to_user_ptr(up->data); - struct io_rsrc_data *data = ctx->file_data; - struct io_fixed_file *file_slot; - struct file *file; - int fd, i, err = 0; - unsigned int done; - bool needs_switch = false; - - if (!ctx->file_data) - return -ENXIO; - if (up->offset + nr_args > ctx->nr_user_files) - return -EINVAL; - - for (done = 0; done < nr_args; done++) { - u64 tag = 0; - - if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) || - copy_from_user(&fd, &fds[done], sizeof(fd))) { - err = -EFAULT; - break; - } - if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) { - err = -EINVAL; - break; - } - if (fd == IORING_REGISTER_FILES_SKIP) - continue; - - i = array_index_nospec(up->offset + done, ctx->nr_user_files); - file_slot = io_fixed_file_slot(&ctx->file_table, i); - - if (file_slot->file_ptr) { - file = (struct file *)(file_slot->file_ptr & FFS_MASK); - err = io_queue_rsrc_removal(data, i, ctx->rsrc_node, file); - if (err) - break; - file_slot->file_ptr = 0; - io_file_bitmap_clear(&ctx->file_table, i); - needs_switch = true; - } - if (fd != -1) { - file = fget(fd); - if (!file) { - err = -EBADF; - break; - } - /* - * 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); - err = -EBADF; - break; - } - err = io_scm_file_account(ctx, file); - if (err) { - fput(file); - break; - } - *io_get_tag_slot(data, i) = tag; - io_fixed_file_set(file_slot, file); - io_file_bitmap_set(&ctx->file_table, i); - } - } - - if (needs_switch) - io_rsrc_node_switch(ctx, data); - return done ? done : err; -} - -static inline void __io_unaccount_mem(struct user_struct *user, - unsigned long nr_pages) -{ - atomic_long_sub(nr_pages, &user->locked_vm); -} - -static inline int __io_account_mem(struct user_struct *user, - unsigned long nr_pages) -{ - unsigned long page_limit, cur_pages, new_pages; - - /* Don't allow more pages than we can safely lock */ - page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; - - do { - cur_pages = atomic_long_read(&user->locked_vm); - new_pages = cur_pages + nr_pages; - if (new_pages > page_limit) - return -ENOMEM; - } while (atomic_long_cmpxchg(&user->locked_vm, cur_pages, - new_pages) != cur_pages); - - return 0; -} - -static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) -{ - if (ctx->user) - __io_unaccount_mem(ctx->user, nr_pages); - - if (ctx->mm_account) - atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm); -} - -static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) -{ - int ret; - - if (ctx->user) { - ret = __io_account_mem(ctx->user, nr_pages); - if (ret) - return ret; - } - - if (ctx->mm_account) - atomic64_add(nr_pages, &ctx->mm_account->pinned_vm); - - return 0; -} - static void io_mem_free(void *ptr) { struct page *page; @@ -4584,423 +3681,6 @@ static unsigned long rings_size(struct io_ring_ctx *ctx, unsigned int sq_entries return off; } -static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot) -{ - struct io_mapped_ubuf *imu = *slot; - unsigned int i; - - if (imu != ctx->dummy_ubuf) { - for (i = 0; i < imu->nr_bvecs; i++) - unpin_user_page(imu->bvec[i].bv_page); - if (imu->acct_pages) - io_unaccount_mem(ctx, imu->acct_pages); - kvfree(imu); - } - *slot = NULL; -} - -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; -} - -static 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; -} - -static 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; -} - -static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst, - void __user *arg, unsigned index) -{ - struct iovec __user *src; - -#ifdef CONFIG_COMPAT - if (ctx->compat) { - struct compat_iovec __user *ciovs; - struct compat_iovec ciov; - - ciovs = (struct compat_iovec __user *) arg; - if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov))) - return -EFAULT; - - dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base); - dst->iov_len = ciov.iov_len; - return 0; - } -#endif - src = (struct iovec __user *) arg; - if (copy_from_user(dst, &src[index], sizeof(*dst))) - return -EFAULT; - return 0; -} - -/* - * 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; - - if (!iov->iov_base) { - *pimu = ctx->dummy_ubuf; - return 0; - } - - *pimu = NULL; - 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; -} - -static int io_buffer_validate(struct iovec *iov) -{ - unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1); - - /* - * Don't impose further limits on the size and buffer - * constraints here, we'll -EINVAL later when IO is - * submitted if they are wrong. - */ - if (!iov->iov_base) - return iov->iov_len ? -EFAULT : 0; - if (!iov->iov_len) - return -EFAULT; - - /* arbitrary limit, but we need something */ - if (iov->iov_len > SZ_1G) - return -EFAULT; - - if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp)) - return -EOVERFLOW; - - return 0; -} - -static 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; - - 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; -} - -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; - 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) { - 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] = NULL; - 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_eventfd_register(struct io_ring_ctx *ctx, void __user *arg, unsigned int eventfd_async) { @@ -5078,12 +3758,6 @@ static void io_req_caches_free(struct io_ring_ctx *ctx) mutex_unlock(&ctx->uring_lock); } -static void io_wait_rsrc_data(struct io_rsrc_data *data) -{ - if (data && !atomic_dec_and_test(&data->refs)) - wait_for_completion(&data->done); -} - static void io_flush_apoll_cache(struct io_ring_ctx *ctx) { struct async_poll *apoll; @@ -6228,89 +4902,6 @@ static int io_register_enable_rings(struct io_ring_ctx *ctx) return 0; } -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; -} - -static 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); -} - -static 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); -} - -static __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; -} - static __cold int io_register_iowq_aff(struct io_ring_ctx *ctx, void __user *arg, unsigned len) { @@ -7103,7 +5694,6 @@ static int __init io_uring_init(void) sizeof(struct io_uring_rsrc_update2)); /* ->buf_index is u16 */ - BUILD_BUG_ON(IORING_MAX_REG_BUFFERS >= (1u << 16)); BUILD_BUG_ON(offsetof(struct io_uring_buf_ring, bufs) != 0); BUILD_BUG_ON(offsetof(struct io_uring_buf, resv) != offsetof(struct io_uring_buf_ring, tail)); |