fs: Document file_ra_state

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/

diff --git a/include/linux/fs.h b/include/linux/fs.h
index ec8f3dd..33831a8 100644 (file)
--- 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;
 };
 
 /*