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[firefly-linux-kernel-4.4.55.git] / fs / pipe.c

diff --git a/fs/pipe.c b/fs/pipe.c
index a58d7ee7ad183a8e6bafa4474bf96c85c1c69f1c..0499a96287ad29713ab4635982c676ea0974233a 100644 (file)
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -345,6 +345,16 @@ static const struct pipe_buf_operations anon_pipe_buf_ops = {
        .get = generic_pipe_buf_get,
 };
 
+static const struct pipe_buf_operations packet_pipe_buf_ops = {
+       .can_merge = 0,
+       .map = generic_pipe_buf_map,
+       .unmap = generic_pipe_buf_unmap,
+       .confirm = generic_pipe_buf_confirm,
+       .release = anon_pipe_buf_release,
+       .steal = generic_pipe_buf_steal,
+       .get = generic_pipe_buf_get,
+};
+
 static ssize_t
 pipe_read(struct kiocb *iocb, const struct iovec *_iov,
           unsigned long nr_segs, loff_t pos)
@@ -406,6 +416,13 @@ redo:
                        ret += chars;
                        buf->offset += chars;
                        buf->len -= chars;
+
+                       /* Was it a packet buffer? Clean up and exit */
+                       if (buf->flags & PIPE_BUF_FLAG_PACKET) {
+                               total_len = chars;
+                               buf->len = 0;
+                       }
+
                        if (!buf->len) {
                                buf->ops = NULL;
                                ops->release(pipe, buf);
@@ -441,7 +458,7 @@ redo:
                        break;
                }
                if (do_wakeup) {
-                       wake_up_interruptible_sync(&pipe->wait);
+                       wake_up_interruptible_sync_poll(&pipe->wait, POLLOUT | POLLWRNORM);
                        kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
                }
                pipe_wait(pipe);
@@ -450,7 +467,7 @@ redo:
 
        /* Signal writers asynchronously that there is more room. */
        if (do_wakeup) {
-               wake_up_interruptible_sync(&pipe->wait);
+               wake_up_interruptible_sync_poll(&pipe->wait, POLLOUT | POLLWRNORM);
                kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
        }
        if (ret > 0)
@@ -458,6 +475,11 @@ redo:
        return ret;
 }
 
+static inline int is_packetized(struct file *file)
+{
+       return (file->f_flags & O_DIRECT) != 0;
+}
+
 static ssize_t
 pipe_write(struct kiocb *iocb, const struct iovec *_iov,
            unsigned long nr_segs, loff_t ppos)
@@ -592,6 +614,11 @@ redo2:
                        buf->ops = &anon_pipe_buf_ops;
                        buf->offset = 0;
                        buf->len = chars;
+                       buf->flags = 0;
+                       if (is_packetized(filp)) {
+                               buf->ops = &packet_pipe_buf_ops;
+                               buf->flags = PIPE_BUF_FLAG_PACKET;
+                       }
                        pipe->nrbufs = ++bufs;
                        pipe->tmp_page = NULL;
 
@@ -612,7 +639,7 @@ redo2:
                        break;
                }
                if (do_wakeup) {
-                       wake_up_interruptible_sync(&pipe->wait);
+                       wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLRDNORM);
                        kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
                        do_wakeup = 0;
                }
@@ -623,7 +650,7 @@ redo2:
 out:
        mutex_unlock(&inode->i_mutex);
        if (do_wakeup) {
-               wake_up_interruptible_sync(&pipe->wait);
+               wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLRDNORM);
                kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
        }
        if (ret > 0)
@@ -715,7 +742,7 @@ pipe_release(struct inode *inode, int decr, int decw)
        if (!pipe->readers && !pipe->writers) {
                free_pipe_info(inode);
        } else {
-               wake_up_interruptible_sync(&pipe->wait);
+               wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM | POLLERR | POLLHUP);
                kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
                kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
        }
@@ -954,6 +981,8 @@ static struct inode * get_pipe_inode(void)
        if (!inode)
                goto fail_inode;
 
+       inode->i_ino = get_next_ino();
+
        pipe = alloc_pipe_info(inode);
        if (!pipe)
                goto fail_iput;
@@ -997,12 +1026,11 @@ struct file *create_write_pipe(int flags)
                goto err;
 
        err = -ENOMEM;
-       path.dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &name);
+       path.dentry = d_alloc_pseudo(pipe_mnt->mnt_sb, &name);
        if (!path.dentry)
                goto err_inode;
        path.mnt = mntget(pipe_mnt);
 
-       path.dentry->d_op = &pipefs_dentry_operations;
        d_instantiate(path.dentry, inode);
 
        err = -ENFILE;
@@ -1011,7 +1039,7 @@ struct file *create_write_pipe(int flags)
                goto err_dentry;
        f->f_mapping = inode->i_mapping;
 
-       f->f_flags = O_WRONLY | (flags & O_NONBLOCK);
+       f->f_flags = O_WRONLY | (flags & (O_NONBLOCK | O_DIRECT));
        f->f_version = 0;
 
        return f;
@@ -1055,7 +1083,7 @@ int do_pipe_flags(int *fd, int flags)
        int error;
        int fdw, fdr;
 
-       if (flags & ~(O_CLOEXEC | O_NONBLOCK))
+       if (flags & ~(O_CLOEXEC | O_NONBLOCK | O_DIRECT))
                return -EINVAL;
 
        fw = create_write_pipe(flags);
@@ -1251,22 +1279,26 @@ out:
        return ret;
 }
 
+static const struct super_operations pipefs_ops = {
+       .destroy_inode = free_inode_nonrcu,
+};
+
 /*
  * pipefs should _never_ be mounted by userland - too much of security hassle,
  * no real gain from having the whole whorehouse mounted. So we don't need
  * any operations on the root directory. However, we need a non-trivial
  * d_name - pipe: will go nicely and kill the special-casing in procfs.
  */
-static int pipefs_get_sb(struct file_system_type *fs_type,
-                        int flags, const char *dev_name, void *data,
-                        struct vfsmount *mnt)
+static struct dentry *pipefs_mount(struct file_system_type *fs_type,
+                        int flags, const char *dev_name, void *data)
 {
-       return get_sb_pseudo(fs_type, "pipe:", NULL, PIPEFS_MAGIC, mnt);
+       return mount_pseudo(fs_type, "pipe:", &pipefs_ops,
+                       &pipefs_dentry_operations, PIPEFS_MAGIC);
 }
 
 static struct file_system_type pipe_fs_type = {
        .name           = "pipefs",
-       .get_sb         = pipefs_get_sb,
+       .mount          = pipefs_mount,
        .kill_sb        = kill_anon_super,
 };