fs: Remove ->readpages address space operation

All filesystems have now been converted to use ->readahead, so
remove the ->readpages operation and fix all the comments that
used to refer to it.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>

3 files changed, 3 insertions, 20 deletions

diff --git a/Documentation/filesystems/fsverity.rst b/Documentation/filesystems/fsverity.rst
index 1d831e3cbcb3..8cc536d08f51 100644
--- a/Documentation/filesystems/fsverity.rst
+++ b/Documentation/filesystems/fsverity.rst
@@ -549,7 +549,7 @@ Pagecache
 ~~~~~~~~~
 
 For filesystems using Linux's pagecache, the ``->readpage()`` and
-``->readpages()`` methods must be modified to verify pages before they
+``->readahead()`` methods must be modified to verify pages before they
 are marked Uptodate.  Merely hooking ``->read_iter()`` would be
 insufficient, since ``->read_iter()`` is not used for memory maps.
 
@@ -611,7 +611,7 @@ workqueue, and then the workqueue work does the decryption or
 verification.  Finally, pages where no decryption or verity error
 occurred are marked Uptodate, and the pages are unlocked.
 
-Files on ext4 and f2fs may contain holes.  Normally, ``->readpages()``
+Files on ext4 and f2fs may contain holes.  Normally, ``->readahead()``
 simply zeroes holes and sets the corresponding pages Uptodate; no bios
 are issued.  To prevent this case from bypassing fs-verity, these
 filesystems use fsverity_verify_page() to verify hole pages.
@@ -778,7 +778,7 @@ weren't already directly answered in other parts of this document.
     - To prevent bypassing verification, pages must not be marked
       Uptodate until they've been verified.  Currently, each
       filesystem is responsible for marking pages Uptodate via
-      ``->readpages()``.  Therefore, currently it's not possible for
+      ``->readahead()``.  Therefore, currently it's not possible for
       the VFS to do the verification on its own.  Changing this would
       require significant changes to the VFS and all filesystems.
 
diff --git a/Documentation/filesystems/locking.rst b/Documentation/filesystems/locking.rst
index 2998cec9af4b..c26d854275a0 100644
--- a/Documentation/filesystems/locking.rst
+++ b/Documentation/filesystems/locking.rst
@@ -241,8 +241,6 @@ prototypes::
 	int (*writepages)(struct address_space *, struct writeback_control *);
 	bool (*dirty_folio)(struct address_space *, struct folio *folio);
 	void (*readahead)(struct readahead_control *);
-	int (*readpages)(struct file *filp, struct address_space *mapping,
-			struct list_head *pages, unsigned nr_pages);
 	int (*write_begin)(struct file *, struct address_space *mapping,
 				loff_t pos, unsigned len, unsigned flags,
 				struct page **pagep, void **fsdata);
@@ -274,7 +272,6 @@ readpage:		yes, unlocks				shared
 writepages:
 dirty_folio		maybe
 readahead:		yes, unlocks				shared
-readpages:		no					shared
 write_begin:		locks the page		 exclusive
 write_end:		yes, unlocks		 exclusive
 bmap:
@@ -300,9 +297,6 @@ completion.
 
 ->readahead() unlocks the pages that I/O is attempted on like ->readpage().
 
-->readpages() populates the pagecache with the passed pages and starts
-I/O against them.  They come unlocked upon I/O completion.
-
 ->writepage() is used for two purposes: for "memory cleansing" and for
 "sync".  These are quite different operations and the behaviour may differ
 depending upon the mode.
diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst
index 4f14edf93941..794bd1a66bfb 100644
--- a/Documentation/filesystems/vfs.rst
+++ b/Documentation/filesystems/vfs.rst
@@ -726,8 +726,6 @@ cache in your filesystem.  The following members are defined:
 		int (*writepages)(struct address_space *, struct writeback_control *);
 		bool (*dirty_folio)(struct address_space *, struct folio *);
 		void (*readahead)(struct readahead_control *);
-		int (*readpages)(struct file *filp, struct address_space *mapping,
-				 struct list_head *pages, unsigned nr_pages);
 		int (*write_begin)(struct file *, struct address_space *mapping,
 				   loff_t pos, unsigned len, unsigned flags,
 				struct page **pagep, void **fsdata);
@@ -817,15 +815,6 @@ cache in your filesystem.  The following members are defined:
 	completes successfully.  Setting PageError on any page will be
 	ignored; simply unlock the page if an I/O error occurs.
 
-``readpages``
-	called by the VM to read pages associated with the address_space
-	object.  This is essentially just a vector version of readpage.
-	Instead of just one page, several pages are requested.
-	readpages is only used for read-ahead, so read errors are
-	ignored.  If anything goes wrong, feel free to give up.
-	This interface is deprecated and will be removed by the end of
-	2020; implement readahead instead.
-
 ``write_begin``
 	Called by the generic buffered write code to ask the filesystem
 	to prepare to write len bytes at the given offset in the file.