mm/filemap: rename generic_file_buffered_read subfunctions

Patch series "Refactor generic_file_buffered_read", v5.

This is a combination of Christoph's work to refactor
generic_file_buffered_read() and some of my large-page support
which was disrupted by Kent's refactoring of generic_file_buffered_read.

This patch (of 18):

The recent split of generic_file_buffered_read() created some very long
function names which are hard to distinguish from each other.  Rename as
follows:

generic_file_buffered_read_readpage -> filemap_read_page
generic_file_buffered_read_pagenotuptodate -> filemap_update_page
generic_file_buffered_read_no_cached_page -> filemap_create_page
generic_file_buffered_read_get_pages -> filemap_get_pages

Link: https://lkml.kernel.org/r/20210122160140.223228-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20210122160140.223228-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Kent Overstreet <kent.overstreet@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/filemap.c b/mm/filemap.c
index 774a869..fbfea44 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2178,11 +2178,8 @@ static int lock_page_for_iocb(struct kiocb *iocb, struct page *page)
                return lock_page_killable(page);
 }
 
-static struct page *
-generic_file_buffered_read_readpage(struct kiocb *iocb,
-                                   struct file *filp,
-                                   struct address_space *mapping,
-                                   struct page *page)
+static struct page *filemap_read_page(struct kiocb *iocb, struct file *filp,
+               struct address_space *mapping, struct page *page)
 {
        struct file_ra_state *ra = &filp->f_ra;
        int error;
@@ -2233,12 +2230,9 @@ generic_file_buffered_read_readpage(struct kiocb *iocb,
        return page;
 }
 
-static struct page *
-generic_file_buffered_read_pagenotuptodate(struct kiocb *iocb,
-                                          struct file *filp,
-                                          struct iov_iter *iter,
-                                          struct page *page,
-                                          loff_t pos, loff_t count)
+static struct page *filemap_update_page(struct kiocb *iocb, struct file *filp,
+               struct iov_iter *iter, struct page *page, loff_t pos,
+               loff_t count)
 {
        struct address_space *mapping = filp->f_mapping;
        struct inode *inode = mapping->host;
@@ -2301,12 +2295,11 @@ page_not_up_to_date_locked:
                return page;
        }
 
-       return generic_file_buffered_read_readpage(iocb, filp, mapping, page);
+       return filemap_read_page(iocb, filp, mapping, page);
 }
 
-static struct page *
-generic_file_buffered_read_no_cached_page(struct kiocb *iocb,
-                                         struct iov_iter *iter)
+static struct page *filemap_create_page(struct kiocb *iocb,
+               struct iov_iter *iter)
 {
        struct file *filp = iocb->ki_filp;
        struct address_space *mapping = filp->f_mapping;
@@ -2317,10 +2310,6 @@ generic_file_buffered_read_no_cached_page(struct kiocb *iocb,
        if (iocb->ki_flags & IOCB_NOIO)
                return ERR_PTR(-EAGAIN);
 
-       /*
-        * Ok, it wasn't cached, so we need to create a new
-        * page..
-        */
        page = page_cache_alloc(mapping);
        if (!page)
                return ERR_PTR(-ENOMEM);
@@ -2332,13 +2321,11 @@ generic_file_buffered_read_no_cached_page(struct kiocb *iocb,
                return error != -EEXIST ? ERR_PTR(error) : NULL;
        }
 
-       return generic_file_buffered_read_readpage(iocb, filp, mapping, page);
+       return filemap_read_page(iocb, filp, mapping, page);
 }
 
-static int generic_file_buffered_read_get_pages(struct kiocb *iocb,
-                                               struct iov_iter *iter,
-                                               struct page **pages,
-                                               unsigned int nr)
+static int filemap_get_pages(struct kiocb *iocb, struct iov_iter *iter,
+               struct page **pages, unsigned int nr)
 {
        struct file *filp = iocb->ki_filp;
        struct address_space *mapping = filp->f_mapping;
@@ -2365,7 +2352,7 @@ find_page:
        if (nr_got)
                goto got_pages;
 
-       pages[0] = generic_file_buffered_read_no_cached_page(iocb, iter);
+       pages[0] = filemap_create_page(iocb, iter);
        err = PTR_ERR_OR_ZERO(pages[0]);
        if (!IS_ERR_OR_NULL(pages[0]))
                nr_got = 1;
@@ -2399,8 +2386,8 @@ got_pages:
                                break;
                        }
 
-                       page = generic_file_buffered_read_pagenotuptodate(iocb,
-                                       filp, iter, page, pg_pos, pg_count);
+                       page = filemap_update_page(iocb, filp, iter, page,
+                                       pg_pos, pg_count);
                        if (IS_ERR_OR_NULL(page)) {
                                for (j = i + 1; j < nr_got; j++)
                                        put_page(pages[j]);
@@ -2479,8 +2466,7 @@ ssize_t generic_file_buffered_read(struct kiocb *iocb,
                        iocb->ki_flags |= IOCB_NOWAIT;
 
                i = 0;
-               pg_nr = generic_file_buffered_read_get_pages(iocb, iter,
-                                                            pages, nr_pages);
+               pg_nr = filemap_get_pages(iocb, iter, pages, nr_pages);
                if (pg_nr < 0) {
                        error = pg_nr;
                        break;