[PATCH v7 04/31] fs: Document file_ra_state

David Howells
2021-04-23T13:29:30Z

From: Matthew Wilcox (Oracle) <willy@infradead.org>

Turn the comments into kernel-doc and improve the wording slightly.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
Link: https://lore.kernel.org/r/20210407201857.3582797-3-willy@infradead.org/
Link: https://lore.kernel.org/r/161789068619.6155.1397999970593531574.stgit@warthog.procyon.org.uk/ # v6
---

include/linux/fs.h | 24 ++++++++++++++----------
1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index ec8f3ddf4a6a..33831a8bda52 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -891,18 +891,22 @@ struct fown_struct {
int signum; /* posix.1b rt signal to be delivered on IO */
};

-/*
- * Track a single file's readahead state
+/**
+ * struct file_ra_state - Track a file's readahead state.
+ * @start: Where the most recent readahead started.
+ * @size: Number of pages read in the most recent readahead.
+ * @async_size: Start next readahead when this many pages are left.
+ * @ra_pages: Maximum size of a readahead request.
+ * @mmap_miss: How many mmap accesses missed in the page cache.
+ * @prev_pos: The last byte in the most recent read request.
*/
struct file_ra_state {
- pgoff_t start; /* where readahead started */
- unsigned int size; /* # of readahead pages */
- unsigned int async_size; /* do asynchronous readahead when
- there are only # of pages ahead */
-
- unsigned int ra_pages; /* Maximum readahead window */
- unsigned int mmap_miss; /* Cache miss stat for mmap accesses */
- loff_t prev_pos; /* Cache last read() position */
+ pgoff_t start;
+ unsigned int size;
+ unsigned int async_size;
+ unsigned int ra_pages;
+ unsigned int mmap_miss;
+ loff_t prev_pos;
};

/*