[PATCH 01/16] fs: add an iopoll method to struct file_operations
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REVIEWED: 1 (0M)
From: Jens Axboe <axboe@kernel.dk>
Date: 2019-01-15 02:55:16
Also in:
linux-arch, linux-fsdevel
Subsystem:
documentation, filesystems (vfs and infrastructure), the rest · Maintainers:
Jonathan Corbet, Alexander Viro, Christian Brauner, Linus Torvalds
1 review trailer.
Possibly related (same subject, not in this thread)
- 2019-01-12 · [PATCH 01/16] fs: add an iopoll method to struct file_operations · Jens Axboe <axboe@kernel.dk>
- 2019-01-08 · [PATCH 01/16] fs: add an iopoll method to struct file_operations · Jens Axboe <axboe@kernel.dk>
From: Christoph Hellwig <hch@lst.de> This new methods is used to explicitly poll for I/O completion for an iocb. It must be called for any iocb submitted asynchronously (that is with a non-null ki_complete) which has the IOCB_HIPRI flag set. The method is assisted by a new ki_cookie field in struct iocb to store the polling cookie. TODO: we can probably union ki_cookie with the existing hint and I/O priority fields to avoid struct kiocb growth. Reviewed-by: Johannes Thumshirn <redacted> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> --- Documentation/filesystems/vfs.txt | 3 +++ include/linux/fs.h | 2 ++ 2 files changed, 5 insertions(+)
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index 8dc8e9c2913f..761c6fd24a53 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt@@ -857,6 +857,7 @@ struct file_operations { ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *); ssize_t (*read_iter) (struct kiocb *, struct iov_iter *); ssize_t (*write_iter) (struct kiocb *, struct iov_iter *); + int (*iopoll)(struct kiocb *kiocb, bool spin); int (*iterate) (struct file *, struct dir_context *); int (*iterate_shared) (struct file *, struct dir_context *); __poll_t (*poll) (struct file *, struct poll_table_struct *);
@@ -902,6 +903,8 @@ otherwise noted. write_iter: possibly asynchronous write with iov_iter as source + iopoll: called when aio wants to poll for completions on HIPRI iocbs + iterate: called when the VFS needs to read the directory contents iterate_shared: called when the VFS needs to read the directory contents
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 811c77743dad..ccb0b7a63aa5 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h@@ -310,6 +310,7 @@ struct kiocb { int ki_flags; u16 ki_hint; u16 ki_ioprio; /* See linux/ioprio.h */ + unsigned int ki_cookie; /* for ->iopoll */ } __randomize_layout; static inline bool is_sync_kiocb(struct kiocb *kiocb)
@@ -1786,6 +1787,7 @@ struct file_operations { ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *); ssize_t (*read_iter) (struct kiocb *, struct iov_iter *); ssize_t (*write_iter) (struct kiocb *, struct iov_iter *); + int (*iopoll)(struct kiocb *kiocb, bool spin); int (*iterate) (struct file *, struct dir_context *); int (*iterate_shared) (struct file *, struct dir_context *); __poll_t (*poll) (struct file *, struct poll_table_struct *);
--
2.17.1