[PATCH v5 06/13] fs: Convert mpage_readpages to mpage_readahead

From: Matthew Wilcox
Date: Mon Feb 10 2020 - 20:04:47 EST


From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>

Implement the new readahead aop and convert all callers (block_dev,
exfat, ext2, fat, gfs2, hpfs, isofs, jfs, nilfs2, ocfs2, omfs, qnx6,
reiserfs & udf). The callers are all trivial except for GFS2 & OCFS2.

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
drivers/staging/exfat/exfat_super.c | 7 +++---
fs/block_dev.c | 7 +++---
fs/ext2/inode.c | 10 +++-----
fs/fat/inode.c | 7 +++---
fs/gfs2/aops.c | 23 ++++++-----------
fs/hpfs/file.c | 7 +++---
fs/iomap/buffered-io.c | 2 +-
fs/isofs/inode.c | 7 +++---
fs/jfs/inode.c | 7 +++---
fs/mpage.c | 38 +++++++++--------------------
fs/nilfs2/inode.c | 15 +++---------
fs/ocfs2/aops.c | 34 ++++++++++----------------
fs/omfs/file.c | 7 +++---
fs/qnx6/inode.c | 7 +++---
fs/reiserfs/inode.c | 8 +++---
fs/udf/inode.c | 7 +++---
include/linux/mpage.h | 4 +--
mm/migrate.c | 2 +-
18 files changed, 74 insertions(+), 125 deletions(-)

diff --git a/drivers/staging/exfat/exfat_super.c b/drivers/staging/exfat/exfat_super.c
index b81d2a87b82e..96aad9b16d31 100644
--- a/drivers/staging/exfat/exfat_super.c
+++ b/drivers/staging/exfat/exfat_super.c
@@ -3002,10 +3002,9 @@ static int exfat_readpage(struct file *file, struct page *page)
return mpage_readpage(page, exfat_get_block);
}

-static int exfat_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned int nr_pages)
+static void exfat_readahead(struct readahead_control *rac)
{
- return mpage_readpages(mapping, pages, nr_pages, exfat_get_block);
+ mpage_readahead(rac, exfat_get_block);
}

static int exfat_writepage(struct page *page, struct writeback_control *wbc)
@@ -3104,7 +3103,7 @@ static sector_t _exfat_bmap(struct address_space *mapping, sector_t block)

static const struct address_space_operations exfat_aops = {
.readpage = exfat_readpage,
- .readpages = exfat_readpages,
+ .readahead = exfat_readahead,
.writepage = exfat_writepage,
.writepages = exfat_writepages,
.write_begin = exfat_write_begin,
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 69bf2fb6f7cd..2fd9c7bd61f6 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -614,10 +614,9 @@ static int blkdev_readpage(struct file * file, struct page * page)
return block_read_full_page(page, blkdev_get_block);
}

-static int blkdev_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
+static void blkdev_readahead(struct readahead_control *rac)
{
- return mpage_readpages(mapping, pages, nr_pages, blkdev_get_block);
+ mpage_readahead(rac, blkdev_get_block);
}

static int blkdev_write_begin(struct file *file, struct address_space *mapping,
@@ -2062,7 +2061,7 @@ static int blkdev_writepages(struct address_space *mapping,

static const struct address_space_operations def_blk_aops = {
.readpage = blkdev_readpage,
- .readpages = blkdev_readpages,
+ .readahead = blkdev_readahead,
.writepage = blkdev_writepage,
.write_begin = blkdev_write_begin,
.write_end = blkdev_write_end,
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 119667e65890..2a65387f9b12 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -877,11 +877,9 @@ static int ext2_readpage(struct file *file, struct page *page)
return mpage_readpage(page, ext2_get_block);
}

-static int
-ext2_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
+static void ext2_readahead(struct readahead_control *rac)
{
- return mpage_readpages(mapping, pages, nr_pages, ext2_get_block);
+ mpage_readahead(rac, ext2_get_block);
}

static int
@@ -966,7 +964,7 @@ ext2_dax_writepages(struct address_space *mapping, struct writeback_control *wbc

const struct address_space_operations ext2_aops = {
.readpage = ext2_readpage,
- .readpages = ext2_readpages,
+ .readahead = ext2_readahead,
.writepage = ext2_writepage,
.write_begin = ext2_write_begin,
.write_end = ext2_write_end,
@@ -980,7 +978,7 @@ const struct address_space_operations ext2_aops = {

const struct address_space_operations ext2_nobh_aops = {
.readpage = ext2_readpage,
- .readpages = ext2_readpages,
+ .readahead = ext2_readahead,
.writepage = ext2_nobh_writepage,
.write_begin = ext2_nobh_write_begin,
.write_end = nobh_write_end,
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 594b05ae16c9..3496f5fc3e6d 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -210,10 +210,9 @@ static int fat_readpage(struct file *file, struct page *page)
return mpage_readpage(page, fat_get_block);
}

-static int fat_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
+static void fat_readahead(struct readahead_control *rac)
{
- return mpage_readpages(mapping, pages, nr_pages, fat_get_block);
+ mpage_readahead(rac, fat_get_block);
}

static void fat_write_failed(struct address_space *mapping, loff_t to)
@@ -344,7 +343,7 @@ int fat_block_truncate_page(struct inode *inode, loff_t from)

static const struct address_space_operations fat_aops = {
.readpage = fat_readpage,
- .readpages = fat_readpages,
+ .readahead = fat_readahead,
.writepage = fat_writepage,
.writepages = fat_writepages,
.write_begin = fat_write_begin,
diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index ba83b49ce18c..5e63c13c12c1 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -577,7 +577,7 @@ int gfs2_internal_read(struct gfs2_inode *ip, char *buf, loff_t *pos,
}

/**
- * gfs2_readpages - Read a bunch of pages at once
+ * gfs2_readahead - Read a bunch of pages at once
* @file: The file to read from
* @mapping: Address space info
* @pages: List of pages to read
@@ -590,31 +590,24 @@ int gfs2_internal_read(struct gfs2_inode *ip, char *buf, loff_t *pos,
* obviously not something we'd want to do on too regular a basis.
* Any I/O we ignore at this time will be done via readpage later.
* 2. We don't handle stuffed files here we let readpage do the honours.
- * 3. mpage_readpages() does most of the heavy lifting in the common case.
+ * 3. mpage_readahead() does most of the heavy lifting in the common case.
* 4. gfs2_block_map() is relied upon to set BH_Boundary in the right places.
*/

-static int gfs2_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
+static void gfs2_readahead(struct readahead_control *rac)
{
- struct inode *inode = mapping->host;
+ struct inode *inode = rac->mapping->host;
struct gfs2_inode *ip = GFS2_I(inode);
- struct gfs2_sbd *sdp = GFS2_SB(inode);
struct gfs2_holder gh;
- int ret;

gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
- ret = gfs2_glock_nq(&gh);
- if (unlikely(ret))
+ if (gfs2_glock_nq(&gh))
goto out_uninit;
if (!gfs2_is_stuffed(ip))
- ret = mpage_readpages(mapping, pages, nr_pages, gfs2_block_map);
+ mpage_readahead(rac, gfs2_block_map);
gfs2_glock_dq(&gh);
out_uninit:
gfs2_holder_uninit(&gh);
- if (unlikely(gfs2_withdrawn(sdp)))
- ret = -EIO;
- return ret;
}

/**
@@ -828,7 +821,7 @@ static const struct address_space_operations gfs2_aops = {
.writepage = gfs2_writepage,
.writepages = gfs2_writepages,
.readpage = gfs2_readpage,
- .readpages = gfs2_readpages,
+ .readahead = gfs2_readahead,
.bmap = gfs2_bmap,
.invalidatepage = gfs2_invalidatepage,
.releasepage = gfs2_releasepage,
@@ -842,7 +835,7 @@ static const struct address_space_operations gfs2_jdata_aops = {
.writepage = gfs2_jdata_writepage,
.writepages = gfs2_jdata_writepages,
.readpage = gfs2_readpage,
- .readpages = gfs2_readpages,
+ .readahead = gfs2_readahead,
.set_page_dirty = jdata_set_page_dirty,
.bmap = gfs2_bmap,
.invalidatepage = gfs2_invalidatepage,
diff --git a/fs/hpfs/file.c b/fs/hpfs/file.c
index b36abf9cb345..2de0d3492d15 100644
--- a/fs/hpfs/file.c
+++ b/fs/hpfs/file.c
@@ -125,10 +125,9 @@ static int hpfs_writepage(struct page *page, struct writeback_control *wbc)
return block_write_full_page(page, hpfs_get_block, wbc);
}

-static int hpfs_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
+static void hpfs_readahead(struct readahead_control *rac)
{
- return mpage_readpages(mapping, pages, nr_pages, hpfs_get_block);
+ mpage_readahead(rac, hpfs_get_block);
}

static int hpfs_writepages(struct address_space *mapping,
@@ -198,7 +197,7 @@ static int hpfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
const struct address_space_operations hpfs_aops = {
.readpage = hpfs_readpage,
.writepage = hpfs_writepage,
- .readpages = hpfs_readpages,
+ .readahead = hpfs_readahead,
.writepages = hpfs_writepages,
.write_begin = hpfs_write_begin,
.write_end = hpfs_write_end,
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 7c84c4c027c4..cb3511eb152a 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -359,7 +359,7 @@ iomap_readpage(struct page *page, const struct iomap_ops *ops)
}

/*
- * Just like mpage_readpages and block_read_full_page we always
+ * Just like mpage_readahead and block_read_full_page we always
* return 0 and just mark the page as PageError on errors. This
* should be cleaned up all through the stack eventually.
*/
diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index 62c0462dc89f..95b1f377ad09 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -1185,10 +1185,9 @@ static int isofs_readpage(struct file *file, struct page *page)
return mpage_readpage(page, isofs_get_block);
}

-static int isofs_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
+static void isofs_readahead(struct readahead_control *rac)
{
- return mpage_readpages(mapping, pages, nr_pages, isofs_get_block);
+ mpage_readahead(rac, isofs_get_block);
}

static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
@@ -1198,7 +1197,7 @@ static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)

static const struct address_space_operations isofs_aops = {
.readpage = isofs_readpage,
- .readpages = isofs_readpages,
+ .readahead = isofs_readahead,
.bmap = _isofs_bmap
};

diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c
index 9486afcdac76..6f65bfa9f18d 100644
--- a/fs/jfs/inode.c
+++ b/fs/jfs/inode.c
@@ -296,10 +296,9 @@ static int jfs_readpage(struct file *file, struct page *page)
return mpage_readpage(page, jfs_get_block);
}

-static int jfs_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
+static void jfs_readahead(struct readahead_control *rac)
{
- return mpage_readpages(mapping, pages, nr_pages, jfs_get_block);
+ mpage_readahead(rac, jfs_get_block);
}

static void jfs_write_failed(struct address_space *mapping, loff_t to)
@@ -358,7 +357,7 @@ static ssize_t jfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)

const struct address_space_operations jfs_aops = {
.readpage = jfs_readpage,
- .readpages = jfs_readpages,
+ .readahead = jfs_readahead,
.writepage = jfs_writepage,
.writepages = jfs_writepages,
.write_begin = jfs_write_begin,
diff --git a/fs/mpage.c b/fs/mpage.c
index ccba3c4c4479..166a95ec1341 100644
--- a/fs/mpage.c
+++ b/fs/mpage.c
@@ -91,7 +91,7 @@ mpage_alloc(struct block_device *bdev,
}

/*
- * support function for mpage_readpages. The fs supplied get_block might
+ * support function for mpage_readahead. The fs supplied get_block might
* return an up to date buffer. This is used to map that buffer into
* the page, which allows readpage to avoid triggering a duplicate call
* to get_block.
@@ -338,13 +338,10 @@ static struct bio *do_mpage_readpage(struct mpage_readpage_args *args)
}

/**
- * mpage_readpages - populate an address space with some pages & start reads against them
+ * mpage_readahead - start reads against pages
* @mapping: the address_space
- * @pages: The address of a list_head which contains the target pages. These
- * pages have their ->index populated and are otherwise uninitialised.
- * The page at @pages->prev has the lowest file offset, and reads should be
- * issued in @pages->prev to @pages->next order.
- * @nr_pages: The number of pages at *@pages
+ * @start: The number of the first page to read.
+ * @nr_pages: The number of consecutive pages to read.
* @get_block: The filesystem's block mapper function.
*
* This function walks the pages and the blocks within each page, building and
@@ -381,36 +378,25 @@ static struct bio *do_mpage_readpage(struct mpage_readpage_args *args)
*
* This all causes the disk requests to be issued in the correct order.
*/
-int
-mpage_readpages(struct address_space *mapping, struct list_head *pages,
- unsigned nr_pages, get_block_t get_block)
+void mpage_readahead(struct readahead_control *rac, get_block_t get_block)
{
+ struct page *page;
struct mpage_readpage_args args = {
.get_block = get_block,
.is_readahead = true,
};
- unsigned page_idx;
-
- for (page_idx = 0; page_idx < nr_pages; page_idx++) {
- struct page *page = lru_to_page(pages);

+ readahead_for_each(rac, page) {
prefetchw(&page->flags);
- list_del(&page->lru);
- if (!add_to_page_cache_lru(page, mapping,
- page->index,
- readahead_gfp_mask(mapping))) {
- args.page = page;
- args.nr_pages = nr_pages - page_idx;
- args.bio = do_mpage_readpage(&args);
- }
+ args.page = page;
+ args.nr_pages = readahead_count(rac);
+ args.bio = do_mpage_readpage(&args);
put_page(page);
}
- BUG_ON(!list_empty(pages));
if (args.bio)
mpage_bio_submit(REQ_OP_READ, REQ_RAHEAD, args.bio);
- return 0;
}
-EXPORT_SYMBOL(mpage_readpages);
+EXPORT_SYMBOL(mpage_readahead);

/*
* This isn't called much at all
@@ -563,7 +549,7 @@ static int __mpage_writepage(struct page *page, struct writeback_control *wbc,
* Page has buffers, but they are all unmapped. The page was
* created by pagein or read over a hole which was handled by
* block_read_full_page(). If this address_space is also
- * using mpage_readpages then this can rarely happen.
+ * using mpage_readahead then this can rarely happen.
*/
goto confused;
}
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 671085512e0f..ceeb3b441844 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -145,18 +145,9 @@ static int nilfs_readpage(struct file *file, struct page *page)
return mpage_readpage(page, nilfs_get_block);
}

-/**
- * nilfs_readpages() - implement readpages() method of nilfs_aops {}
- * address_space_operations.
- * @file - file struct of the file to be read
- * @mapping - address_space struct used for reading multiple pages
- * @pages - the pages to be read
- * @nr_pages - number of pages to be read
- */
-static int nilfs_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned int nr_pages)
+static void nilfs_readahead(struct readahead_control *rac)
{
- return mpage_readpages(mapping, pages, nr_pages, nilfs_get_block);
+ mpage_readahead(rac, nilfs_get_block);
}

static int nilfs_writepages(struct address_space *mapping,
@@ -308,7 +299,7 @@ const struct address_space_operations nilfs_aops = {
.readpage = nilfs_readpage,
.writepages = nilfs_writepages,
.set_page_dirty = nilfs_set_page_dirty,
- .readpages = nilfs_readpages,
+ .readahead = nilfs_readahead,
.write_begin = nilfs_write_begin,
.write_end = nilfs_write_end,
/* .releasepage = nilfs_releasepage, */
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 3a67a6518ddf..e8137efaafec 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -350,14 +350,11 @@ static int ocfs2_readpage(struct file *file, struct page *page)
* grow out to a tree. If need be, detecting boundary extents could
* trivially be added in a future version of ocfs2_get_block().
*/
-static int ocfs2_readpages(struct file *filp, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
+static void ocfs2_readahead(struct readahead_control *rac)
{
- int ret, err = -EIO;
- struct inode *inode = mapping->host;
+ int ret;
+ struct inode *inode = rac->mapping->host;
struct ocfs2_inode_info *oi = OCFS2_I(inode);
- loff_t start;
- struct page *last;

/*
* Use the nonblocking flag for the dlm code to avoid page
@@ -365,36 +362,31 @@ static int ocfs2_readpages(struct file *filp, struct address_space *mapping,
*/
ret = ocfs2_inode_lock_full(inode, NULL, 0, OCFS2_LOCK_NONBLOCK);
if (ret)
- return err;
+ return;

- if (down_read_trylock(&oi->ip_alloc_sem) == 0) {
- ocfs2_inode_unlock(inode, 0);
- return err;
- }
+ if (down_read_trylock(&oi->ip_alloc_sem) == 0)
+ goto out_unlock;

/*
* Don't bother with inline-data. There isn't anything
* to read-ahead in that case anyway...
*/
if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
- goto out_unlock;
+ goto out_up;

/*
* Check whether a remote node truncated this file - we just
* drop out in that case as it's not worth handling here.
*/
- last = lru_to_page(pages);
- start = (loff_t)last->index << PAGE_SHIFT;
- if (start >= i_size_read(inode))
- goto out_unlock;
+ if (readahead_offset(rac) >= i_size_read(inode))
+ goto out_up;

- err = mpage_readpages(mapping, pages, nr_pages, ocfs2_get_block);
+ mpage_readahead(rac, ocfs2_get_block);

-out_unlock:
+out_up:
up_read(&oi->ip_alloc_sem);
+out_unlock:
ocfs2_inode_unlock(inode, 0);
-
- return err;
}

/* Note: Because we don't support holes, our allocation has
@@ -2474,7 +2466,7 @@ static ssize_t ocfs2_direct_IO(struct kiocb *iocb, struct iov_iter *iter)

const struct address_space_operations ocfs2_aops = {
.readpage = ocfs2_readpage,
- .readpages = ocfs2_readpages,
+ .readahead = ocfs2_readahead,
.writepage = ocfs2_writepage,
.write_begin = ocfs2_write_begin,
.write_end = ocfs2_write_end,
diff --git a/fs/omfs/file.c b/fs/omfs/file.c
index d640b9388238..d7b5f09d298c 100644
--- a/fs/omfs/file.c
+++ b/fs/omfs/file.c
@@ -289,10 +289,9 @@ static int omfs_readpage(struct file *file, struct page *page)
return block_read_full_page(page, omfs_get_block);
}

-static int omfs_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
+static void omfs_readahead(struct readahead_control *rac)
{
- return mpage_readpages(mapping, pages, nr_pages, omfs_get_block);
+ mpage_readahead(rac, omfs_get_block);
}

static int omfs_writepage(struct page *page, struct writeback_control *wbc)
@@ -373,7 +372,7 @@ const struct inode_operations omfs_file_inops = {

const struct address_space_operations omfs_aops = {
.readpage = omfs_readpage,
- .readpages = omfs_readpages,
+ .readahead = omfs_readahead,
.writepage = omfs_writepage,
.writepages = omfs_writepages,
.write_begin = omfs_write_begin,
diff --git a/fs/qnx6/inode.c b/fs/qnx6/inode.c
index 345db56c98fd..755293c8c71a 100644
--- a/fs/qnx6/inode.c
+++ b/fs/qnx6/inode.c
@@ -99,10 +99,9 @@ static int qnx6_readpage(struct file *file, struct page *page)
return mpage_readpage(page, qnx6_get_block);
}

-static int qnx6_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
+static void qnx6_readahead(struct readahead_control *rac)
{
- return mpage_readpages(mapping, pages, nr_pages, qnx6_get_block);
+ mpage_readahead(rac, qnx6_get_block);
}

/*
@@ -499,7 +498,7 @@ static sector_t qnx6_bmap(struct address_space *mapping, sector_t block)
}
static const struct address_space_operations qnx6_aops = {
.readpage = qnx6_readpage,
- .readpages = qnx6_readpages,
+ .readahead = qnx6_readahead,
.bmap = qnx6_bmap
};

diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c
index 6419e6dacc39..0031070b3692 100644
--- a/fs/reiserfs/inode.c
+++ b/fs/reiserfs/inode.c
@@ -1160,11 +1160,9 @@ int reiserfs_get_block(struct inode *inode, sector_t block,
return retval;
}

-static int
-reiserfs_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
+static void reiserfs_readahead(struct readahead_control *rac)
{
- return mpage_readpages(mapping, pages, nr_pages, reiserfs_get_block);
+ mpage_readahead(rac, reiserfs_get_block);
}

/*
@@ -3434,7 +3432,7 @@ int reiserfs_setattr(struct dentry *dentry, struct iattr *attr)
const struct address_space_operations reiserfs_address_space_operations = {
.writepage = reiserfs_writepage,
.readpage = reiserfs_readpage,
- .readpages = reiserfs_readpages,
+ .readahead = reiserfs_readahead,
.releasepage = reiserfs_releasepage,
.invalidatepage = reiserfs_invalidatepage,
.write_begin = reiserfs_write_begin,
diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index e875bc5668ee..adaba8e8b326 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -195,10 +195,9 @@ static int udf_readpage(struct file *file, struct page *page)
return mpage_readpage(page, udf_get_block);
}

-static int udf_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
+static void udf_readahead(struct readahead_control *rac)
{
- return mpage_readpages(mapping, pages, nr_pages, udf_get_block);
+ mpage_readahead(rac, udf_get_block);
}

static int udf_write_begin(struct file *file, struct address_space *mapping,
@@ -234,7 +233,7 @@ static sector_t udf_bmap(struct address_space *mapping, sector_t block)

const struct address_space_operations udf_aops = {
.readpage = udf_readpage,
- .readpages = udf_readpages,
+ .readahead = udf_readahead,
.writepage = udf_writepage,
.writepages = udf_writepages,
.write_begin = udf_write_begin,
diff --git a/include/linux/mpage.h b/include/linux/mpage.h
index 001f1fcf9836..f4f5e90a6844 100644
--- a/include/linux/mpage.h
+++ b/include/linux/mpage.h
@@ -13,9 +13,9 @@
#ifdef CONFIG_BLOCK

struct writeback_control;
+struct readahead_control;

-int mpage_readpages(struct address_space *mapping, struct list_head *pages,
- unsigned nr_pages, get_block_t get_block);
+void mpage_readahead(struct readahead_control *, get_block_t get_block);
int mpage_readpage(struct page *page, get_block_t get_block);
int mpage_writepages(struct address_space *mapping,
struct writeback_control *wbc, get_block_t get_block);
diff --git a/mm/migrate.c b/mm/migrate.c
index b1092876e537..a32122095702 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1020,7 +1020,7 @@ static int __unmap_and_move(struct page *page, struct page *newpage,
* to the LRU. Later, when the IO completes the pages are
* marked uptodate and unlocked. However, the queueing
* could be merging multiple pages for one bio (e.g.
- * mpage_readpages). If an allocation happens for the
+ * mpage_readahead). If an allocation happens for the
* second or third page, the process can end up locking
* the same page twice and deadlocking. Rather than
* trying to be clever about what pages can be locked,
--
2.25.0