[PATCH v4 32/36] mm: Make page_cache_readahead_unbounded take a readahead_control

Matthew Wilcox
2020-05-15T13:17:46Z

Define it in the callers instead of in page_cache_readahead_unbounded().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
fs/ext4/verity.c | 4 ++--
fs/f2fs/verity.c | 4 ++--
include/linux/pagemap.h | 5 ++---
mm/readahead.c | 26 ++++++++++++--------------
4 files changed, 18 insertions(+), 21 deletions(-)

diff --git a/fs/ext4/verity.c b/fs/ext4/verity.c
index dec1244dd062..fe2e541543da 100644
--- a/fs/ext4/verity.c
+++ b/fs/ext4/verity.c
@@ -346,6 +346,7 @@ static struct page *ext4_read_merkle_tree_page(struct inode *inode,
pgoff_t index,
unsigned long num_ra_pages)
{
+ DEFINE_READAHEAD(rac, NULL, inode->i_mapping, index);
struct page *page;

index += ext4_verity_metadata_pos(inode) >> PAGE_SHIFT;
@@ -355,8 +356,7 @@ static struct page *ext4_read_merkle_tree_page(struct inode *inode,
if (page)
put_page(page);
else if (num_ra_pages > 1)
- page_cache_readahead_unbounded(inode->i_mapping, NULL,
- index, num_ra_pages, 0);
+ page_cache_readahead_unbounded(&rac, num_ra_pages, 0);
page = read_mapping_page(inode->i_mapping, index, NULL);
}
return page;
diff --git a/fs/f2fs/verity.c b/fs/f2fs/verity.c
index 865c9fb774fb..707a94745472 100644
--- a/fs/f2fs/verity.c
+++ b/fs/f2fs/verity.c
@@ -226,6 +226,7 @@ static struct page *f2fs_read_merkle_tree_page(struct inode *inode,
pgoff_t index,
unsigned long num_ra_pages)
{
+ DEFINE_READAHEAD(rac, NULL, inode->i_mapping, index);
struct page *page;

index += f2fs_verity_metadata_pos(inode) >> PAGE_SHIFT;
@@ -235,8 +236,7 @@ static struct page *f2fs_read_merkle_tree_page(struct inode *inode,
if (page)
put_page(page);
else if (num_ra_pages > 1)
- page_cache_readahead_unbounded(inode->i_mapping, NULL,
- index, num_ra_pages, 0);
+ page_cache_readahead_unbounded(&rac, num_ra_pages, 0);
page = read_mapping_page(inode->i_mapping, index, NULL);
}
return page;
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 29ca36acdfd7..c694a052751f 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -674,9 +674,8 @@ void page_cache_sync_readahead(struct address_space *, struct file_ra_state *,
void page_cache_async_readahead(struct address_space *, struct file_ra_state *,
struct file *, struct page *, pgoff_t index,
unsigned long req_count);
-void page_cache_readahead_unbounded(struct address_space *, struct file *,
- pgoff_t index, unsigned long nr_to_read,
- unsigned long lookahead_count);
+void page_cache_readahead_unbounded(struct readahead_control *,
+ unsigned long nr_to_read, unsigned long lookahead_count);

/*
* Like add_to_page_cache_locked, but used to add newly allocated pages:
diff --git a/mm/readahead.c b/mm/readahead.c
index 2126a2754e22..62da2d4beed1 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -159,9 +159,7 @@ static void read_pages(struct readahead_control *rac, struct list_head *pages,

/**
* page_cache_readahead_unbounded - Start unchecked readahead.
- * @mapping: File address space.
- * @file: This instance of the open file; used for authentication.
- * @index: First page index to read.
+ * @rac: Readahead control.
* @nr_to_read: The number of pages to read.
* @lookahead_size: Where to start the next readahead.
*
@@ -173,13 +171,13 @@ static void read_pages(struct readahead_control *rac, struct list_head *pages,
* Context: File is referenced by caller. Mutexes may be held by caller.
* May sleep, but will not reenter filesystem to reclaim memory.
*/
-void page_cache_readahead_unbounded(struct address_space *mapping,
- struct file *file, pgoff_t index, unsigned long nr_to_read,
- unsigned long lookahead_size)
+void page_cache_readahead_unbounded(struct readahead_control *rac,
+ unsigned long nr_to_read, unsigned long lookahead_size)
{
+ struct address_space *mapping = rac->mapping;
+ unsigned long index = readahead_index(rac);
LIST_HEAD(page_pool);
gfp_t gfp_mask = readahead_gfp_mask(mapping);
- DEFINE_READAHEAD(rac, file, mapping, index);
unsigned long i;

/*
@@ -200,7 +198,7 @@ void page_cache_readahead_unbounded(struct address_space *mapping,
for (i = 0; i < nr_to_read; i++) {
struct page *page = xa_load(&mapping->i_pages, index + i);

- BUG_ON(index + i != rac._index + rac._nr_pages);
+ BUG_ON(index + i != rac->_index + rac->_nr_pages);

if (page && !xa_is_value(page)) {
/*
@@ -211,7 +209,7 @@ void page_cache_readahead_unbounded(struct address_space *mapping,
* have a stable reference to this page, and it's
* not worth getting one just for that.
*/
- read_pages(&rac, &page_pool, true);
+ read_pages(rac, &page_pool, true);
continue;
}

@@ -224,12 +222,12 @@ void page_cache_readahead_unbounded(struct address_space *mapping,
} else if (add_to_page_cache_lru(page, mapping, index + i,
gfp_mask) < 0) {
put_page(page);
- read_pages(&rac, &page_pool, true);
+ read_pages(rac, &page_pool, true);
continue;
}
if (i == nr_to_read - lookahead_size)
SetPageReadahead(page);
- rac._nr_pages++;
+ rac->_nr_pages++;
}

/*
@@ -237,7 +235,7 @@ void page_cache_readahead_unbounded(struct address_space *mapping,
* uptodate then the caller will launch readpage again, and
* will then handle the error.
*/
- read_pages(&rac, &page_pool, false);
+ read_pages(rac, &page_pool, false);
memalloc_nofs_restore(nofs);
}
EXPORT_SYMBOL_GPL(page_cache_readahead_unbounded);
@@ -252,6 +250,7 @@ void __do_page_cache_readahead(struct address_space *mapping,
struct file *file, pgoff_t index, unsigned long nr_to_read,
unsigned long lookahead_size)
{
+ DEFINE_READAHEAD(rac, file, mapping, index);
struct inode *inode = mapping->host;
loff_t isize = i_size_read(inode);
pgoff_t end_index; /* The last page we want to read */
@@ -266,8 +265,7 @@ void __do_page_cache_readahead(struct address_space *mapping,
if (nr_to_read > end_index - index)
nr_to_read = end_index - index + 1;

- page_cache_readahead_unbounded(mapping, file, index, nr_to_read,
- lookahead_size);
+ page_cache_readahead_unbounded(&rac, nr_to_read, lookahead_size);
}

/*
--
2.26.2