Commit b1647dc0 authored by David Howells's avatar David Howells Committed by Linus Torvalds
Browse files

mm/readahead: pass a file_ra_state into force_page_cache_ra 



The file_ra_state being passed into page_cache_sync_readahead() was being
ignored in favour of using the one embedded in the struct file.  The only
caller for which this makes a difference is the fsverity code if the file
has been marked as POSIX_FADV_RANDOM, but it's confusing and worth fixing.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Cc: Eric Biggers <ebiggers@google.com>
Link: https://lkml.kernel.org/r/20200903140844.14194-10-willy@infradead.org


Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent db660d46

mm/internal.h

+3 −2
Original line number Diff line number Diff line
@@ -51,12 +51,13 @@ void unmap_page_range(struct mmu_gather *tlb, 


void do_page_cache_ra(struct readahead_control *, unsigned long nr_to_read,

		unsigned long lookahead_size);

void force_page_cache_ra(struct readahead_control *, unsigned long nr);

void force_page_cache_ra(struct readahead_control *, struct file_ra_state *,

		unsigned long nr);

static inline void force_page_cache_readahead(struct address_space *mapping,

		struct file *file, pgoff_t index, unsigned long nr_to_read)

{

	DEFINE_READAHEAD(ractl, file, mapping, index);

	force_page_cache_ra(&ractl, nr_to_read);

	force_page_cache_ra(&ractl, &file->f_ra, nr_to_read);

}



struct page *find_get_entry(struct address_space *mapping, pgoff_t index);

mm/readahead.c

+2 −3
Original line number Diff line number Diff line
@@ -272,11 +272,10 @@ void do_page_cache_ra(struct readahead_control *ractl, 
 * memory at once.

 */

void force_page_cache_ra(struct readahead_control *ractl,

		unsigned long nr_to_read)

		struct file_ra_state *ra, unsigned long nr_to_read)

{

	struct address_space *mapping = ractl->mapping;

	struct backing_dev_info *bdi = inode_to_bdi(mapping->host);

	struct file_ra_state *ra = &ractl->file->f_ra;

	unsigned long max_pages, index;



	if (unlikely(!mapping->a_ops->readpage && !mapping->a_ops->readpages &&
@@ -562,7 +561,7 @@ void page_cache_sync_ra(struct readahead_control *ractl, 


	/* be dumb */

	if (ractl->file && (ractl->file->f_mode & FMODE_RANDOM)) {

		force_page_cache_ra(ractl, req_count);

		force_page_cache_ra(ractl, ra, req_count);

		return;

	}