#include "io_uring_types.h"
#include "io_uring.h"
+#include "opdef.h"
#include "refs.h"
#include "tctx.h"
#include "sqpoll.h"
#include "net.h"
#include "msg_ring.h"
#include "timeout.h"
+#include "poll.h"
#define IORING_MAX_ENTRIES 32768
#define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
* First field must be the file pointer in all the
* iocb unions! See also 'struct kiocb' in <linux/fs.h>
*/
-struct io_poll {
- struct file *file;
- struct wait_queue_head *head;
- __poll_t events;
- struct wait_queue_entry wait;
-};
-
-struct io_poll_update {
- struct file *file;
- u64 old_user_data;
- u64 new_user_data;
- __poll_t events;
- bool update_events;
- bool update_user_data;
-};
-
struct io_cancel {
struct file *file;
u64 addr;
struct wait_page_queue wpq;
};
-struct async_poll {
- struct io_poll poll;
- struct io_poll *double_poll;
-};
-
enum {
IORING_RSRC_FILE = 0,
IORING_RSRC_BUFFER = 1,
u32 seq;
};
-struct io_op_def {
- /* needs req->file assigned */
- unsigned needs_file : 1;
- /* should block plug */
- unsigned plug : 1;
- /* hash wq insertion if file is a regular file */
- unsigned hash_reg_file : 1;
- /* unbound wq insertion if file is a non-regular file */
- unsigned unbound_nonreg_file : 1;
- /* set if opcode supports polled "wait" */
- unsigned pollin : 1;
- unsigned pollout : 1;
- unsigned poll_exclusive : 1;
- /* op supports buffer selection */
- unsigned buffer_select : 1;
- /* opcode is not supported by this kernel */
- unsigned not_supported : 1;
- /* skip auditing */
- unsigned audit_skip : 1;
- /* supports ioprio */
- unsigned ioprio : 1;
- /* supports iopoll */
- unsigned iopoll : 1;
- /* size of async data needed, if any */
- unsigned short async_size;
-
- const char *name;
-
- int (*prep)(struct io_kiocb *, const struct io_uring_sqe *);
- int (*issue)(struct io_kiocb *, unsigned int);
- int (*prep_async)(struct io_kiocb *);
- void (*cleanup)(struct io_kiocb *);
-};
-
-static const struct io_op_def io_op_defs[];
-
/* requests with any of those set should undergo io_disarm_next() */
#define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL)
#define IO_REQ_LINK_FLAGS (REQ_F_LINK | REQ_F_HARDLINK)
return xa_load(&ctx->io_bl_xa, bgid);
}
-static void io_kbuf_recycle(struct io_kiocb *req, unsigned issue_flags)
+void __io_kbuf_recycle(struct io_kiocb *req, unsigned issue_flags)
{
struct io_ring_ctx *ctx = req->ctx;
struct io_buffer_list *bl;
struct io_buffer *buf;
- if (!(req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING)))
- return;
- /*
- * For legacy provided buffer mode, don't recycle if we already did
- * IO to this buffer. For ring-mapped provided buffer mode, we should
- * increment ring->head to explicitly monopolize the buffer to avoid
- * multiple use.
- */
- if ((req->flags & REQ_F_BUFFER_SELECTED) &&
- (req->flags & REQ_F_PARTIAL_IO))
- return;
-
- /*
- * READV uses fields in `struct io_rw` (len/addr) to stash the selected
- * buffer data. However if that buffer is recycled the original request
- * data stored in addr is lost. Therefore forbid recycling for now.
- */
- if (req->opcode == IORING_OP_READV)
- return;
-
/*
* We don't need to recycle for REQ_F_BUFFER_RING, we can just clear
* the flag and hence ensure that bl->head doesn't get incremented.
* As io_match_task() but protected against racing with linked timeouts.
* User must not hold timeout_lock.
*/
-static bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,
- bool cancel_all)
+bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,
+ bool cancel_all)
{
bool matched;
io_req_complete_post(req);
}
-static void io_req_complete_failed(struct io_kiocb *req, s32 res)
+void io_req_complete_failed(struct io_kiocb *req, s32 res)
{
req_set_fail(req);
io_req_set_res(req, res, io_put_kbuf(req, IO_URING_F_UNLOCKED));
io_req_complete_failed(req, req->cqe.res);
}
-static void io_req_task_submit(struct io_kiocb *req, bool *locked)
+void io_req_task_submit(struct io_kiocb *req, bool *locked)
{
io_tw_lock(req->ctx, locked);
/* req->task == current here, checking PF_EXITING is safe */
return -EOPNOTSUPP;
}
-struct io_poll_table {
- struct poll_table_struct pt;
- struct io_kiocb *req;
- int nr_entries;
- int error;
-};
-
-#define IO_POLL_CANCEL_FLAG BIT(31)
-#define IO_POLL_REF_MASK GENMASK(30, 0)
-
-/*
- * If refs part of ->poll_refs (see IO_POLL_REF_MASK) is 0, it's free. We can
- * bump it and acquire ownership. It's disallowed to modify requests while not
- * owning it, that prevents from races for enqueueing task_work's and b/w
- * arming poll and wakeups.
- */
-static inline bool io_poll_get_ownership(struct io_kiocb *req)
-{
- return !(atomic_fetch_inc(&req->poll_refs) & IO_POLL_REF_MASK);
-}
-
-static void io_poll_mark_cancelled(struct io_kiocb *req)
-{
- atomic_or(IO_POLL_CANCEL_FLAG, &req->poll_refs);
-}
-
-static struct io_poll *io_poll_get_double(struct io_kiocb *req)
-{
- /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
- if (req->opcode == IORING_OP_POLL_ADD)
- return req->async_data;
- return req->apoll->double_poll;
-}
-
-static struct io_poll *io_poll_get_single(struct io_kiocb *req)
-{
- if (req->opcode == IORING_OP_POLL_ADD)
- return io_kiocb_to_cmd(req);
- return &req->apoll->poll;
-}
-
-static void io_poll_req_insert(struct io_kiocb *req)
-{
- struct io_ring_ctx *ctx = req->ctx;
- struct hlist_head *list;
-
- list = &ctx->cancel_hash[hash_long(req->cqe.user_data, ctx->cancel_hash_bits)];
- hlist_add_head(&req->hash_node, list);
-}
-
-static void io_init_poll_iocb(struct io_poll *poll, __poll_t events,
- wait_queue_func_t wake_func)
-{
- poll->head = NULL;
-#define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
- /* mask in events that we always want/need */
- poll->events = events | IO_POLL_UNMASK;
- INIT_LIST_HEAD(&poll->wait.entry);
- init_waitqueue_func_entry(&poll->wait, wake_func);
-}
-
-static inline void io_poll_remove_entry(struct io_poll *poll)
-{
- struct wait_queue_head *head = smp_load_acquire(&poll->head);
-
- if (head) {
- spin_lock_irq(&head->lock);
- list_del_init(&poll->wait.entry);
- poll->head = NULL;
- spin_unlock_irq(&head->lock);
- }
-}
-
-static void io_poll_remove_entries(struct io_kiocb *req)
-{
- /*
- * Nothing to do if neither of those flags are set. Avoid dipping
- * into the poll/apoll/double cachelines if we can.
- */
- if (!(req->flags & (REQ_F_SINGLE_POLL | REQ_F_DOUBLE_POLL)))
- return;
-
- /*
- * While we hold the waitqueue lock and the waitqueue is nonempty,
- * wake_up_pollfree() will wait for us. However, taking the waitqueue
- * lock in the first place can race with the waitqueue being freed.
- *
- * We solve this as eventpoll does: by taking advantage of the fact that
- * all users of wake_up_pollfree() will RCU-delay the actual free. If
- * we enter rcu_read_lock() and see that the pointer to the queue is
- * non-NULL, we can then lock it without the memory being freed out from
- * under us.
- *
- * Keep holding rcu_read_lock() as long as we hold the queue lock, in
- * case the caller deletes the entry from the queue, leaving it empty.
- * In that case, only RCU prevents the queue memory from being freed.
- */
- rcu_read_lock();
- if (req->flags & REQ_F_SINGLE_POLL)
- io_poll_remove_entry(io_poll_get_single(req));
- if (req->flags & REQ_F_DOUBLE_POLL)
- io_poll_remove_entry(io_poll_get_double(req));
- rcu_read_unlock();
-}
-
-static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags);
-/*
- * All poll tw should go through this. Checks for poll events, manages
- * references, does rewait, etc.
- *
- * Returns a negative error on failure. >0 when no action require, which is
- * either spurious wakeup or multishot CQE is served. 0 when it's done with
- * the request, then the mask is stored in req->cqe.res.
- */
-static int io_poll_check_events(struct io_kiocb *req, bool *locked)
-{
- struct io_ring_ctx *ctx = req->ctx;
- int v, ret;
-
- /* req->task == current here, checking PF_EXITING is safe */
- if (unlikely(req->task->flags & PF_EXITING))
- return -ECANCELED;
-
- do {
- v = atomic_read(&req->poll_refs);
-
- /* tw handler should be the owner, and so have some references */
- if (WARN_ON_ONCE(!(v & IO_POLL_REF_MASK)))
- return 0;
- if (v & IO_POLL_CANCEL_FLAG)
- return -ECANCELED;
-
- if (!req->cqe.res) {
- struct poll_table_struct pt = { ._key = req->apoll_events };
- req->cqe.res = vfs_poll(req->file, &pt) & req->apoll_events;
- }
-
- if ((unlikely(!req->cqe.res)))
- continue;
- if (req->apoll_events & EPOLLONESHOT)
- return 0;
-
- /* multishot, just fill a CQE and proceed */
- if (!(req->flags & REQ_F_APOLL_MULTISHOT)) {
- __poll_t mask = mangle_poll(req->cqe.res &
- req->apoll_events);
- bool filled;
-
- spin_lock(&ctx->completion_lock);
- filled = io_fill_cqe_aux(ctx, req->cqe.user_data,
- mask, IORING_CQE_F_MORE);
- io_commit_cqring(ctx);
- spin_unlock(&ctx->completion_lock);
- if (filled) {
- io_cqring_ev_posted(ctx);
- continue;
- }
- return -ECANCELED;
- }
-
- io_tw_lock(req->ctx, locked);
- if (unlikely(req->task->flags & PF_EXITING))
- return -EFAULT;
- ret = io_issue_sqe(req,
- IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
- if (ret)
- return ret;
-
- /*
- * Release all references, retry if someone tried to restart
- * task_work while we were executing it.
- */
- } while (atomic_sub_return(v & IO_POLL_REF_MASK, &req->poll_refs));
-
- return 1;
-}
-
-static void io_poll_task_func(struct io_kiocb *req, bool *locked)
-{
- struct io_ring_ctx *ctx = req->ctx;
- int ret;
-
- ret = io_poll_check_events(req, locked);
- if (ret > 0)
- return;
-
- if (!ret) {
- struct io_poll *poll = io_kiocb_to_cmd(req);
-
- req->cqe.res = mangle_poll(req->cqe.res & poll->events);
- } else {
- req->cqe.res = ret;
- req_set_fail(req);
- }
-
- io_poll_remove_entries(req);
- spin_lock(&ctx->completion_lock);
- hash_del(&req->hash_node);
- req->cqe.flags = 0;
- __io_req_complete_post(req);
- io_commit_cqring(ctx);
- spin_unlock(&ctx->completion_lock);
- io_cqring_ev_posted(ctx);
-}
-
-static void io_apoll_task_func(struct io_kiocb *req, bool *locked)
-{
- struct io_ring_ctx *ctx = req->ctx;
- int ret;
-
- ret = io_poll_check_events(req, locked);
- if (ret > 0)
- return;
-
- io_poll_remove_entries(req);
- spin_lock(&ctx->completion_lock);
- hash_del(&req->hash_node);
- spin_unlock(&ctx->completion_lock);
-
- if (!ret)
- io_req_task_submit(req, locked);
- else
- io_req_complete_failed(req, ret);
-}
-
-static void __io_poll_execute(struct io_kiocb *req, int mask,
- __poll_t __maybe_unused events)
-{
- io_req_set_res(req, mask, 0);
- /*
- * This is useful for poll that is armed on behalf of another
- * request, and where the wakeup path could be on a different
- * CPU. We want to avoid pulling in req->apoll->events for that
- * case.
- */
- if (req->opcode == IORING_OP_POLL_ADD)
- req->io_task_work.func = io_poll_task_func;
- else
- req->io_task_work.func = io_apoll_task_func;
-
- trace_io_uring_task_add(req->ctx, req, req->cqe.user_data, req->opcode, mask);
- io_req_task_work_add(req);
-}
-
-static inline void io_poll_execute(struct io_kiocb *req, int res,
- __poll_t events)
-{
- if (io_poll_get_ownership(req))
- __io_poll_execute(req, res, events);
-}
-
-static void io_poll_cancel_req(struct io_kiocb *req)
-{
- io_poll_mark_cancelled(req);
- /* kick tw, which should complete the request */
- io_poll_execute(req, 0, 0);
-}
-
-#define wqe_to_req(wait) ((void *)((unsigned long) (wait)->private & ~1))
-#define wqe_is_double(wait) ((unsigned long) (wait)->private & 1)
-#define IO_ASYNC_POLL_COMMON (EPOLLONESHOT | EPOLLPRI)
-
-static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
- void *key)
-{
- struct io_kiocb *req = wqe_to_req(wait);
- struct io_poll *poll = container_of(wait, struct io_poll, wait);
- __poll_t mask = key_to_poll(key);
-
- if (unlikely(mask & POLLFREE)) {
- io_poll_mark_cancelled(req);
- /* we have to kick tw in case it's not already */
- io_poll_execute(req, 0, poll->events);
-
- /*
- * If the waitqueue is being freed early but someone is already
- * holds ownership over it, we have to tear down the request as
- * best we can. That means immediately removing the request from
- * its waitqueue and preventing all further accesses to the
- * waitqueue via the request.
- */
- list_del_init(&poll->wait.entry);
-
- /*
- * Careful: this *must* be the last step, since as soon
- * as req->head is NULL'ed out, the request can be
- * completed and freed, since aio_poll_complete_work()
- * will no longer need to take the waitqueue lock.
- */
- smp_store_release(&poll->head, NULL);
- return 1;
- }
-
- /* for instances that support it check for an event match first */
- if (mask && !(mask & (poll->events & ~IO_ASYNC_POLL_COMMON)))
- return 0;
-
- if (io_poll_get_ownership(req)) {
- /* optional, saves extra locking for removal in tw handler */
- if (mask && poll->events & EPOLLONESHOT) {
- list_del_init(&poll->wait.entry);
- poll->head = NULL;
- if (wqe_is_double(wait))
- req->flags &= ~REQ_F_DOUBLE_POLL;
- else
- req->flags &= ~REQ_F_SINGLE_POLL;
- }
- __io_poll_execute(req, mask, poll->events);
- }
- return 1;
-}
-
-static void __io_queue_proc(struct io_poll *poll, struct io_poll_table *pt,
- struct wait_queue_head *head,
- struct io_poll **poll_ptr)
-{
- struct io_kiocb *req = pt->req;
- unsigned long wqe_private = (unsigned long) req;
-
- /*
- * The file being polled uses multiple waitqueues for poll handling
- * (e.g. one for read, one for write). Setup a separate io_poll
- * if this happens.
- */
- if (unlikely(pt->nr_entries)) {
- struct io_poll *first = poll;
-
- /* double add on the same waitqueue head, ignore */
- if (first->head == head)
- return;
- /* already have a 2nd entry, fail a third attempt */
- if (*poll_ptr) {
- if ((*poll_ptr)->head == head)
- return;
- pt->error = -EINVAL;
- return;
- }
-
- poll = kmalloc(sizeof(*poll), GFP_ATOMIC);
- if (!poll) {
- pt->error = -ENOMEM;
- return;
- }
- /* mark as double wq entry */
- wqe_private |= 1;
- req->flags |= REQ_F_DOUBLE_POLL;
- io_init_poll_iocb(poll, first->events, first->wait.func);
- *poll_ptr = poll;
- if (req->opcode == IORING_OP_POLL_ADD)
- req->flags |= REQ_F_ASYNC_DATA;
- }
-
- req->flags |= REQ_F_SINGLE_POLL;
- pt->nr_entries++;
- poll->head = head;
- poll->wait.private = (void *) wqe_private;
-
- if (poll->events & EPOLLEXCLUSIVE)
- add_wait_queue_exclusive(head, &poll->wait);
- else
- add_wait_queue(head, &poll->wait);
-}
-
-static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
- struct poll_table_struct *p)
-{
- struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
- struct io_poll *poll = io_kiocb_to_cmd(pt->req);
-
- __io_queue_proc(poll, pt, head,
- (struct io_poll **) &pt->req->async_data);
-}
-
-static int __io_arm_poll_handler(struct io_kiocb *req,
- struct io_poll *poll,
- struct io_poll_table *ipt, __poll_t mask)
-{
- struct io_ring_ctx *ctx = req->ctx;
- int v;
-
- INIT_HLIST_NODE(&req->hash_node);
- req->work.cancel_seq = atomic_read(&ctx->cancel_seq);
- io_init_poll_iocb(poll, mask, io_poll_wake);
- poll->file = req->file;
-
- req->apoll_events = poll->events;
-
- ipt->pt._key = mask;
- ipt->req = req;
- ipt->error = 0;
- ipt->nr_entries = 0;
-
- /*
- * Take the ownership to delay any tw execution up until we're done
- * with poll arming. see io_poll_get_ownership().
- */
- atomic_set(&req->poll_refs, 1);
- mask = vfs_poll(req->file, &ipt->pt) & poll->events;
-
- if (mask && (poll->events & EPOLLONESHOT)) {
- io_poll_remove_entries(req);
- /* no one else has access to the req, forget about the ref */
- return mask;
- }
- if (!mask && unlikely(ipt->error || !ipt->nr_entries)) {
- io_poll_remove_entries(req);
- if (!ipt->error)
- ipt->error = -EINVAL;
- return 0;
- }
-
- spin_lock(&ctx->completion_lock);
- io_poll_req_insert(req);
- spin_unlock(&ctx->completion_lock);
-
- if (mask) {
- /* can't multishot if failed, just queue the event we've got */
- if (unlikely(ipt->error || !ipt->nr_entries)) {
- poll->events |= EPOLLONESHOT;
- req->apoll_events |= EPOLLONESHOT;
- ipt->error = 0;
- }
- __io_poll_execute(req, mask, poll->events);
- return 0;
- }
-
- /*
- * Release ownership. If someone tried to queue a tw while it was
- * locked, kick it off for them.
- */
- v = atomic_dec_return(&req->poll_refs);
- if (unlikely(v & IO_POLL_REF_MASK))
- __io_poll_execute(req, 0, poll->events);
- return 0;
-}
-
-static void io_async_queue_proc(struct file *file, struct wait_queue_head *head,
- struct poll_table_struct *p)
-{
- struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
- struct async_poll *apoll = pt->req->apoll;
-
- __io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll);
-}
-
-enum {
- IO_APOLL_OK,
- IO_APOLL_ABORTED,
- IO_APOLL_READY
-};
-
-static int io_arm_poll_handler(struct io_kiocb *req, unsigned issue_flags)
-{
- const struct io_op_def *def = &io_op_defs[req->opcode];
- struct io_ring_ctx *ctx = req->ctx;
- struct async_poll *apoll;
- struct io_poll_table ipt;
- __poll_t mask = POLLPRI | POLLERR;
- int ret;
-
- if (!def->pollin && !def->pollout)
- return IO_APOLL_ABORTED;
- if (!file_can_poll(req->file))
- return IO_APOLL_ABORTED;
- if ((req->flags & (REQ_F_POLLED|REQ_F_PARTIAL_IO)) == REQ_F_POLLED)
- return IO_APOLL_ABORTED;
- if (!(req->flags & REQ_F_APOLL_MULTISHOT))
- mask |= EPOLLONESHOT;
-
- if (def->pollin) {
- mask |= EPOLLIN | EPOLLRDNORM;
-
- /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
- if (req->flags & REQ_F_CLEAR_POLLIN)
- mask &= ~EPOLLIN;
- } else {
- mask |= EPOLLOUT | EPOLLWRNORM;
- }
- if (def->poll_exclusive)
- mask |= EPOLLEXCLUSIVE;
- if (req->flags & REQ_F_POLLED) {
- apoll = req->apoll;
- kfree(apoll->double_poll);
- } else if (!(issue_flags & IO_URING_F_UNLOCKED) &&
- !list_empty(&ctx->apoll_cache)) {
- apoll = list_first_entry(&ctx->apoll_cache, struct async_poll,
- poll.wait.entry);
- list_del_init(&apoll->poll.wait.entry);
- } else {
- apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC);
- if (unlikely(!apoll))
- return IO_APOLL_ABORTED;
- }
- apoll->double_poll = NULL;
- req->apoll = apoll;
- req->flags |= REQ_F_POLLED;
- ipt.pt._qproc = io_async_queue_proc;
-
- io_kbuf_recycle(req, issue_flags);
-
- ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask);
- if (ret || ipt.error)
- return ret ? IO_APOLL_READY : IO_APOLL_ABORTED;
-
- trace_io_uring_poll_arm(ctx, req, req->cqe.user_data, req->opcode,
- mask, apoll->poll.events);
- return IO_APOLL_OK;
-}
-
-/*
- * Returns true if we found and killed one or more poll requests
- */
-static __cold bool io_poll_remove_all(struct io_ring_ctx *ctx,
- struct task_struct *tsk, bool cancel_all)
-{
- struct hlist_node *tmp;
- struct io_kiocb *req;
- bool found = false;
- int i;
-
- spin_lock(&ctx->completion_lock);
- for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
- struct hlist_head *list;
-
- list = &ctx->cancel_hash[i];
- hlist_for_each_entry_safe(req, tmp, list, hash_node) {
- if (io_match_task_safe(req, tsk, cancel_all)) {
- hlist_del_init(&req->hash_node);
- io_poll_cancel_req(req);
- found = true;
- }
- }
- }
- spin_unlock(&ctx->completion_lock);
- return found;
-}
-
-static struct io_kiocb *io_poll_find(struct io_ring_ctx *ctx, bool poll_only,
- struct io_cancel_data *cd)
- __must_hold(&ctx->completion_lock)
-{
- struct hlist_head *list;
- struct io_kiocb *req;
-
- list = &ctx->cancel_hash[hash_long(cd->data, ctx->cancel_hash_bits)];
- hlist_for_each_entry(req, list, hash_node) {
- if (cd->data != req->cqe.user_data)
- continue;
- if (poll_only && req->opcode != IORING_OP_POLL_ADD)
- continue;
- if (cd->flags & IORING_ASYNC_CANCEL_ALL) {
- if (cd->seq == req->work.cancel_seq)
- continue;
- req->work.cancel_seq = cd->seq;
- }
- return req;
- }
- return NULL;
-}
-
-static struct io_kiocb *io_poll_file_find(struct io_ring_ctx *ctx,
- struct io_cancel_data *cd)
- __must_hold(&ctx->completion_lock)
-{
- struct io_kiocb *req;
- int i;
-
- for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
- struct hlist_head *list;
-
- list = &ctx->cancel_hash[i];
- hlist_for_each_entry(req, list, hash_node) {
- if (!(cd->flags & IORING_ASYNC_CANCEL_ANY) &&
- req->file != cd->file)
- continue;
- if (cd->seq == req->work.cancel_seq)
- continue;
- req->work.cancel_seq = cd->seq;
- return req;
- }
- }
- return NULL;
-}
-
-static bool io_poll_disarm(struct io_kiocb *req)
- __must_hold(&ctx->completion_lock)
-{
- if (!io_poll_get_ownership(req))
- return false;
- io_poll_remove_entries(req);
- hash_del(&req->hash_node);
- return true;
-}
-
-static int io_poll_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd)
- __must_hold(&ctx->completion_lock)
-{
- struct io_kiocb *req;
-
- if (cd->flags & (IORING_ASYNC_CANCEL_FD|IORING_ASYNC_CANCEL_ANY))
- req = io_poll_file_find(ctx, cd);
- else
- req = io_poll_find(ctx, false, cd);
- if (!req)
- return -ENOENT;
- io_poll_cancel_req(req);
- return 0;
-}
-
-static __poll_t io_poll_parse_events(const struct io_uring_sqe *sqe,
- unsigned int flags)
-{
- u32 events;
-
- events = READ_ONCE(sqe->poll32_events);
-#ifdef __BIG_ENDIAN
- events = swahw32(events);
-#endif
- if (!(flags & IORING_POLL_ADD_MULTI))
- events |= EPOLLONESHOT;
- return demangle_poll(events) | (events & (EPOLLEXCLUSIVE|EPOLLONESHOT));
-}
-
-static int io_poll_remove_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- struct io_poll_update *upd = io_kiocb_to_cmd(req);
- u32 flags;
-
- if (sqe->buf_index || sqe->splice_fd_in)
- return -EINVAL;
- flags = READ_ONCE(sqe->len);
- if (flags & ~(IORING_POLL_UPDATE_EVENTS | IORING_POLL_UPDATE_USER_DATA |
- IORING_POLL_ADD_MULTI))
- return -EINVAL;
- /* meaningless without update */
- if (flags == IORING_POLL_ADD_MULTI)
- return -EINVAL;
-
- upd->old_user_data = READ_ONCE(sqe->addr);
- upd->update_events = flags & IORING_POLL_UPDATE_EVENTS;
- upd->update_user_data = flags & IORING_POLL_UPDATE_USER_DATA;
-
- upd->new_user_data = READ_ONCE(sqe->off);
- if (!upd->update_user_data && upd->new_user_data)
- return -EINVAL;
- if (upd->update_events)
- upd->events = io_poll_parse_events(sqe, flags);
- else if (sqe->poll32_events)
- return -EINVAL;
-
- return 0;
-}
-
-static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- struct io_poll *poll = io_kiocb_to_cmd(req);
- u32 flags;
-
- if (sqe->buf_index || sqe->off || sqe->addr)
- return -EINVAL;
- flags = READ_ONCE(sqe->len);
- if (flags & ~IORING_POLL_ADD_MULTI)
- return -EINVAL;
- if ((flags & IORING_POLL_ADD_MULTI) && (req->flags & REQ_F_CQE_SKIP))
- return -EINVAL;
-
- io_req_set_refcount(req);
- poll->events = io_poll_parse_events(sqe, flags);
- return 0;
-}
-
-static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_poll *poll = io_kiocb_to_cmd(req);
- struct io_poll_table ipt;
- int ret;
-
- ipt.pt._qproc = io_poll_queue_proc;
-
- ret = __io_arm_poll_handler(req, poll, &ipt, poll->events);
- if (ret) {
- io_req_set_res(req, ret, 0);
- return IOU_OK;
- }
- if (ipt.error) {
- req_set_fail(req);
- return ipt.error;
- }
-
- return IOU_ISSUE_SKIP_COMPLETE;
-}
-
-static int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_poll_update *poll_update = io_kiocb_to_cmd(req);
- struct io_cancel_data cd = { .data = poll_update->old_user_data, };
- struct io_ring_ctx *ctx = req->ctx;
- struct io_kiocb *preq;
- int ret2, ret = 0;
- bool locked;
-
- spin_lock(&ctx->completion_lock);
- preq = io_poll_find(ctx, true, &cd);
- if (!preq || !io_poll_disarm(preq)) {
- spin_unlock(&ctx->completion_lock);
- ret = preq ? -EALREADY : -ENOENT;
- goto out;
- }
- spin_unlock(&ctx->completion_lock);
-
- if (poll_update->update_events || poll_update->update_user_data) {
- /* only mask one event flags, keep behavior flags */
- if (poll_update->update_events) {
- struct io_poll *poll = io_kiocb_to_cmd(preq);
-
- poll->events &= ~0xffff;
- poll->events |= poll_update->events & 0xffff;
- poll->events |= IO_POLL_UNMASK;
- }
- if (poll_update->update_user_data)
- preq->cqe.user_data = poll_update->new_user_data;
-
- ret2 = io_poll_add(preq, issue_flags);
- /* successfully updated, don't complete poll request */
- if (!ret2 || ret2 == -EIOCBQUEUED)
- goto out;
- }
-
- req_set_fail(preq);
- io_req_set_res(preq, -ECANCELED, 0);
- locked = !(issue_flags & IO_URING_F_UNLOCKED);
- io_req_task_complete(preq, &locked);
-out:
- if (ret < 0) {
- req_set_fail(req);
- return ret;
- }
- /* complete update request, we're done with it */
- io_req_set_res(req, ret, 0);
- return IOU_OK;
-}
-
static bool io_cancel_cb(struct io_wq_work *work, void *data)
{
struct io_kiocb *req = container_of(work, struct io_kiocb, work);
return 0;
}
+int io_poll_issue(struct io_kiocb *req, bool *locked)
+{
+ io_tw_lock(req->ctx, locked);
+ if (unlikely(req->task->flags & PF_EXITING))
+ return -EFAULT;
+ return io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
+}
+
struct io_wq_work *io_wq_free_work(struct io_wq_work *work)
{
struct io_kiocb *req = container_of(work, struct io_kiocb, work);
return -ECANCELED;
}
-static const struct io_op_def io_op_defs[] = {
+const struct io_op_def io_op_defs[] = {
[IORING_OP_NOP] = {
.audit_skip = 1,
.iopoll = 1,
projects / linux-block.git / blobdiff