drm/i915: Add debugfs file to clear FIFO underruns.

[sfrench/cifs-2.6.git] / fs / pipe.c

diff --git a/fs/pipe.c b/fs/pipe.c
index 8be52158c400cf765006433bd2389aa71a1f048a..7b1954caf3885d1c24458aa3a1843802c0506a09 100644 (file)
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -327,7 +327,7 @@ pipe_read(struct kiocb *iocb, struct iov_iter *to)
                        break;
                }
                if (do_wakeup) {
-                       wake_up_interruptible_sync_poll(&pipe->wait, POLLOUT | POLLWRNORM);
+                       wake_up_interruptible_sync_poll(&pipe->wait, EPOLLOUT | EPOLLWRNORM);
                        kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
                }
                pipe_wait(pipe);
@@ -336,7 +336,7 @@ pipe_read(struct kiocb *iocb, struct iov_iter *to)
 
        /* Signal writers asynchronously that there is more room. */
        if (do_wakeup) {
-               wake_up_interruptible_sync_poll(&pipe->wait, POLLOUT | POLLWRNORM);
+               wake_up_interruptible_sync_poll(&pipe->wait, EPOLLOUT | EPOLLWRNORM);
                kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
        }
        if (ret > 0)
@@ -463,7 +463,7 @@ pipe_write(struct kiocb *iocb, struct iov_iter *from)
                        break;
                }
                if (do_wakeup) {
-                       wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLRDNORM);
+                       wake_up_interruptible_sync_poll(&pipe->wait, EPOLLIN | EPOLLRDNORM);
                        kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
                        do_wakeup = 0;
                }
@@ -474,7 +474,7 @@ pipe_write(struct kiocb *iocb, struct iov_iter *from)
 out:
        __pipe_unlock(pipe);
        if (do_wakeup) {
-               wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLRDNORM);
+               wake_up_interruptible_sync_poll(&pipe->wait, EPOLLIN | EPOLLRDNORM);
                kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
        }
        if (ret > 0 && sb_start_write_trylock(file_inode(filp)->i_sb)) {
@@ -523,19 +523,19 @@ pipe_poll(struct file *filp, poll_table *wait)
        nrbufs = pipe->nrbufs;
        mask = 0;
        if (filp->f_mode & FMODE_READ) {
-               mask = (nrbufs > 0) ? POLLIN | POLLRDNORM : 0;
+               mask = (nrbufs > 0) ? EPOLLIN | EPOLLRDNORM : 0;
                if (!pipe->writers && filp->f_version != pipe->w_counter)
-                       mask |= POLLHUP;
+                       mask |= EPOLLHUP;
        }
 
        if (filp->f_mode & FMODE_WRITE) {
-               mask |= (nrbufs < pipe->buffers) ? POLLOUT | POLLWRNORM : 0;
+               mask |= (nrbufs < pipe->buffers) ? EPOLLOUT | EPOLLWRNORM : 0;
                /*
-                * Most Unices do not set POLLERR for FIFOs but on Linux they
+                * Most Unices do not set EPOLLERR for FIFOs but on Linux they
                 * behave exactly like pipes for poll().
                 */
                if (!pipe->readers)
-                       mask |= POLLERR;
+                       mask |= EPOLLERR;
        }
 
        return mask;
@@ -568,7 +568,7 @@ pipe_release(struct inode *inode, struct file *file)
                pipe->writers--;
 
        if (pipe->readers || pipe->writers) {
-               wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM | POLLERR | POLLHUP);
+               wake_up_interruptible_sync_poll(&pipe->wait, EPOLLIN | EPOLLOUT | EPOLLRDNORM | EPOLLWRNORM | EPOLLERR | EPOLLHUP);
                kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
                kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
        }
@@ -605,12 +605,16 @@ static unsigned long account_pipe_buffers(struct user_struct *user,
 
 static bool too_many_pipe_buffers_soft(unsigned long user_bufs)
 {
-       return pipe_user_pages_soft && user_bufs > pipe_user_pages_soft;
+       unsigned long soft_limit = READ_ONCE(pipe_user_pages_soft);
+
+       return soft_limit && user_bufs > soft_limit;
 }
 
 static bool too_many_pipe_buffers_hard(unsigned long user_bufs)
 {
-       return pipe_user_pages_hard && user_bufs > pipe_user_pages_hard;
+       unsigned long hard_limit = READ_ONCE(pipe_user_pages_hard);
+
+       return hard_limit && user_bufs > hard_limit;
 }
 
 static bool is_unprivileged_user(void)
@@ -624,13 +628,14 @@ struct pipe_inode_info *alloc_pipe_info(void)
        unsigned long pipe_bufs = PIPE_DEF_BUFFERS;
        struct user_struct *user = get_current_user();
        unsigned long user_bufs;
+       unsigned int max_size = READ_ONCE(pipe_max_size);
 
        pipe = kzalloc(sizeof(struct pipe_inode_info), GFP_KERNEL_ACCOUNT);
        if (pipe == NULL)
                goto out_free_uid;
 
-       if (pipe_bufs * PAGE_SIZE > pipe_max_size && !capable(CAP_SYS_RESOURCE))
-               pipe_bufs = pipe_max_size >> PAGE_SHIFT;
+       if (pipe_bufs * PAGE_SIZE > max_size && !capable(CAP_SYS_RESOURCE))
+               pipe_bufs = max_size >> PAGE_SHIFT;
 
        user_bufs = account_pipe_buffers(user, 0, pipe_bufs);
 
@@ -931,7 +936,7 @@ static int fifo_open(struct inode *inode, struct file *filp)
 
                if (!is_pipe && !pipe->writers) {
                        if ((filp->f_flags & O_NONBLOCK)) {
-                               /* suppress POLLHUP until we have
+                               /* suppress EPOLLHUP until we have
                                 * seen a writer */
                                filp->f_version = pipe->w_counter;
                        } else {