diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/aio.c | 148 | ||||
| -rw-r--r-- | fs/eventfd.c | 19 | ||||
| -rw-r--r-- | fs/eventpoll.c | 15 | ||||
| -rw-r--r-- | fs/pipe.c | 22 | ||||
| -rw-r--r-- | fs/select.c | 23 | ||||
| -rw-r--r-- | fs/timerfd.c | 22 |
6 files changed, 32 insertions, 217 deletions
@@ -5,7 +5,6 @@ * Implements an efficient asynchronous io interface. * * Copyright 2000, 2001, 2002 Red Hat, Inc. All Rights Reserved. - * Copyright 2018 Christoph Hellwig. * * See ../COPYING for licensing terms. */ @@ -165,22 +164,10 @@ struct fsync_iocb { bool datasync; }; -struct poll_iocb { - struct file *file; - __poll_t events; - struct wait_queue_head *head; - - union { - struct wait_queue_entry wait; - struct work_struct work; - }; -}; - struct aio_kiocb { union { struct kiocb rw; struct fsync_iocb fsync; - struct poll_iocb poll; }; struct kioctx *ki_ctx; @@ -1590,6 +1577,7 @@ static int aio_fsync(struct fsync_iocb *req, struct iocb *iocb, bool datasync) if (unlikely(iocb->aio_buf || iocb->aio_offset || iocb->aio_nbytes || iocb->aio_rw_flags)) return -EINVAL; + req->file = fget(iocb->aio_fildes); if (unlikely(!req->file)) return -EBADF; @@ -1604,137 +1592,6 @@ static int aio_fsync(struct fsync_iocb *req, struct iocb *iocb, bool datasync) return 0; } -/* need to use list_del_init so we can check if item was present */ -static inline bool __aio_poll_remove(struct poll_iocb *req) -{ - if (list_empty(&req->wait.entry)) - return false; - list_del_init(&req->wait.entry); - return true; -} - -static inline void __aio_poll_complete(struct aio_kiocb *iocb, __poll_t mask) -{ - fput(iocb->poll.file); - aio_complete(iocb, mangle_poll(mask), 0); -} - -static void aio_poll_work(struct work_struct *work) -{ - struct aio_kiocb *iocb = container_of(work, struct aio_kiocb, poll.work); - - if (!list_empty_careful(&iocb->ki_list)) - aio_remove_iocb(iocb); - __aio_poll_complete(iocb, iocb->poll.events); -} - -static int aio_poll_cancel(struct kiocb *iocb) -{ - struct aio_kiocb *aiocb = container_of(iocb, struct aio_kiocb, rw); - struct poll_iocb *req = &aiocb->poll; - struct wait_queue_head *head = req->head; - bool found = false; - - spin_lock(&head->lock); - found = __aio_poll_remove(req); - spin_unlock(&head->lock); - - if (found) { - req->events = 0; - INIT_WORK(&req->work, aio_poll_work); - schedule_work(&req->work); - } - return 0; -} - -static int aio_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync, - void *key) -{ - struct poll_iocb *req = container_of(wait, struct poll_iocb, wait); - struct aio_kiocb *iocb = container_of(req, struct aio_kiocb, poll); - struct file *file = req->file; - __poll_t mask = key_to_poll(key); - - assert_spin_locked(&req->head->lock); - - /* for instances that support it check for an event match first: */ - if (mask && !(mask & req->events)) - return 0; - - mask = file->f_op->poll_mask(file, req->events) & req->events; - if (!mask) - return 0; - - __aio_poll_remove(req); - - /* - * Try completing without a context switch if we can acquire ctx_lock - * without spinning. Otherwise we need to defer to a workqueue to - * avoid a deadlock due to the lock order. - */ - if (spin_trylock(&iocb->ki_ctx->ctx_lock)) { - list_del_init(&iocb->ki_list); - spin_unlock(&iocb->ki_ctx->ctx_lock); - - __aio_poll_complete(iocb, mask); - } else { - req->events = mask; - INIT_WORK(&req->work, aio_poll_work); - schedule_work(&req->work); - } - - return 1; -} - -static ssize_t aio_poll(struct aio_kiocb *aiocb, struct iocb *iocb) -{ - struct kioctx *ctx = aiocb->ki_ctx; - struct poll_iocb *req = &aiocb->poll; - __poll_t mask; - - /* reject any unknown events outside the normal event mask. */ - if ((u16)iocb->aio_buf != iocb->aio_buf) - return -EINVAL; - /* reject fields that are not defined for poll */ - if (iocb->aio_offset || iocb->aio_nbytes || iocb->aio_rw_flags) - return -EINVAL; - - req->events = demangle_poll(iocb->aio_buf) | EPOLLERR | EPOLLHUP; - req->file = fget(iocb->aio_fildes); - if (unlikely(!req->file)) - return -EBADF; - if (!file_has_poll_mask(req->file)) - goto out_fail; - - req->head = req->file->f_op->get_poll_head(req->file, req->events); - if (!req->head) - goto out_fail; - if (IS_ERR(req->head)) { - mask = EPOLLERR; - goto done; - } - - init_waitqueue_func_entry(&req->wait, aio_poll_wake); - aiocb->ki_cancel = aio_poll_cancel; - - spin_lock_irq(&ctx->ctx_lock); - spin_lock(&req->head->lock); - mask = req->file->f_op->poll_mask(req->file, req->events) & req->events; - if (!mask) { - __add_wait_queue(req->head, &req->wait); - list_add_tail(&aiocb->ki_list, &ctx->active_reqs); - } - spin_unlock(&req->head->lock); - spin_unlock_irq(&ctx->ctx_lock); -done: - if (mask) - __aio_poll_complete(aiocb, mask); - return 0; -out_fail: - fput(req->file); - return -EINVAL; /* same as no support for IOCB_CMD_POLL */ -} - static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, bool compat) { @@ -1808,9 +1665,6 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, case IOCB_CMD_FDSYNC: ret = aio_fsync(&req->fsync, &iocb, true); break; - case IOCB_CMD_POLL: - ret = aio_poll(req, &iocb); - break; default: pr_debug("invalid aio operation %d\n", iocb.aio_lio_opcode); ret = -EINVAL; diff --git a/fs/eventfd.c b/fs/eventfd.c index ceb1031..08d3bd6 100644 --- a/fs/eventfd.c +++ b/fs/eventfd.c @@ -101,20 +101,14 @@ static int eventfd_release(struct inode *inode, struct file *file) return 0; } -static struct wait_queue_head * -eventfd_get_poll_head(struct file *file, __poll_t events) -{ - struct eventfd_ctx *ctx = file->private_data; - - return &ctx->wqh; -} - -static __poll_t eventfd_poll_mask(struct file *file, __poll_t eventmask) +static __poll_t eventfd_poll(struct file *file, poll_table *wait) { struct eventfd_ctx *ctx = file->private_data; __poll_t events = 0; u64 count; + poll_wait(file, &ctx->wqh, wait); + /* * All writes to ctx->count occur within ctx->wqh.lock. This read * can be done outside ctx->wqh.lock because we know that poll_wait @@ -156,11 +150,11 @@ static __poll_t eventfd_poll_mask(struct file *file, __poll_t eventmask) count = READ_ONCE(ctx->count); if (count > 0) - events |= (EPOLLIN & eventmask); + events |= EPOLLIN; if (count == ULLONG_MAX) events |= EPOLLERR; if (ULLONG_MAX - 1 > count) - events |= (EPOLLOUT & eventmask); + events |= EPOLLOUT; return events; } @@ -311,8 +305,7 @@ static const struct file_operations eventfd_fops = { .show_fdinfo = eventfd_show_fdinfo, #endif .release = eventfd_release, - .get_poll_head = eventfd_get_poll_head, - .poll_mask = eventfd_poll_mask, + .poll = eventfd_poll, .read = eventfd_read, .write = eventfd_write, .llseek = noop_llseek, diff --git a/fs/eventpoll.c b/fs/eventpoll.c index ea4436f..67db22f 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -922,18 +922,14 @@ static __poll_t ep_read_events_proc(struct eventpoll *ep, struct list_head *head return 0; } -static struct wait_queue_head *ep_eventpoll_get_poll_head(struct file *file, - __poll_t eventmask) -{ - struct eventpoll *ep = file->private_data; - return &ep->poll_wait; -} - -static __poll_t ep_eventpoll_poll_mask(struct file *file, __poll_t eventmask) +static __poll_t ep_eventpoll_poll(struct file *file, poll_table *wait) { struct eventpoll *ep = file->private_data; int depth = 0; + /* Insert inside our poll wait queue */ + poll_wait(file, &ep->poll_wait, wait); + /* * Proceed to find out if wanted events are really available inside * the ready list. @@ -972,8 +968,7 @@ static const struct file_operations eventpoll_fops = { .show_fdinfo = ep_show_fdinfo, #endif .release = ep_eventpoll_release, - .get_poll_head = ep_eventpoll_get_poll_head, - .poll_mask = ep_eventpoll_poll_mask, + .poll = ep_eventpoll_poll, .llseek = noop_llseek, }; @@ -509,22 +509,19 @@ static long pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) } } -static struct wait_queue_head * -pipe_get_poll_head(struct file *filp, __poll_t events) -{ - struct pipe_inode_info *pipe = filp->private_data; - - return &pipe->wait; -} - /* No kernel lock held - fine */ -static __poll_t pipe_poll_mask(struct file *filp, __poll_t events) +static __poll_t +pipe_poll(struct file *filp, poll_table *wait) { + __poll_t mask; struct pipe_inode_info *pipe = filp->private_data; - int nrbufs = pipe->nrbufs; - __poll_t mask = 0; + int nrbufs; + + poll_wait(filp, &pipe->wait, wait); /* Reading only -- no need for acquiring the semaphore. */ + nrbufs = pipe->nrbufs; + mask = 0; if (filp->f_mode & FMODE_READ) { mask = (nrbufs > 0) ? EPOLLIN | EPOLLRDNORM : 0; if (!pipe->writers && filp->f_version != pipe->w_counter) @@ -1023,8 +1020,7 @@ const struct file_operations pipefifo_fops = { .llseek = no_llseek, .read_iter = pipe_read, .write_iter = pipe_write, - .get_poll_head = pipe_get_poll_head, - .poll_mask = pipe_poll_mask, + .poll = pipe_poll, .unlocked_ioctl = pipe_ioctl, .release = pipe_release, .fasync = pipe_fasync, diff --git a/fs/select.c b/fs/select.c index 317891f..4a6b6e4 100644 --- a/fs/select.c +++ b/fs/select.c @@ -34,29 +34,6 @@ #include <linux/uaccess.h> -__poll_t vfs_poll(struct file *file, struct poll_table_struct *pt) -{ - if (file->f_op->poll) { - return file->f_op->poll(file, pt); - } else if (file_has_poll_mask(file)) { - unsigned int events = poll_requested_events(pt); - struct wait_queue_head *head; - - if (pt && pt->_qproc) { - head = file->f_op->get_poll_head(file, events); - if (!head) - return DEFAULT_POLLMASK; - if (IS_ERR(head)) - return EPOLLERR; - pt->_qproc(file, head, pt); - } - - return file->f_op->poll_mask(file, events); - } else { - return DEFAULT_POLLMASK; - } -} -EXPORT_SYMBOL_GPL(vfs_poll); /* * Estimate expected accuracy in ns from a timeval. diff --git a/fs/timerfd.c b/fs/timerfd.c index d84a2be..cdad49d 100644 --- a/fs/timerfd.c +++ b/fs/timerfd.c @@ -226,20 +226,21 @@ static int timerfd_release(struct inode *inode, struct file *file) kfree_rcu(ctx, rcu); return 0; } - -static struct wait_queue_head *timerfd_get_poll_head(struct file *file, - __poll_t eventmask) + +static __poll_t timerfd_poll(struct file *file, poll_table *wait) { struct timerfd_ctx *ctx = file->private_data; + __poll_t events = 0; + unsigned long flags; - return &ctx->wqh; -} + poll_wait(file, &ctx->wqh, wait); -static __poll_t timerfd_poll_mask(struct file *file, __poll_t eventmask) -{ - struct timerfd_ctx *ctx = file->private_data; + spin_lock_irqsave(&ctx->wqh.lock, flags); + if (ctx->ticks) + events |= EPOLLIN; + spin_unlock_irqrestore(&ctx->wqh.lock, flags); - return ctx->ticks ? EPOLLIN : 0; + return events; } static ssize_t timerfd_read(struct file *file, char __user *buf, size_t count, @@ -363,8 +364,7 @@ static long timerfd_ioctl(struct file *file, unsigned int cmd, unsigned long arg static const struct file_operations timerfd_fops = { .release = timerfd_release, - .get_poll_head = timerfd_get_poll_head, - .poll_mask = timerfd_poll_mask, + .poll = timerfd_poll, .read = timerfd_read, .llseek = noop_llseek, .show_fdinfo = timerfd_show, |
