As Jens reported, we'd better assign REQ_RAHEAD to bio by the fact that
->readpages is called only from read-ahead.
In Documentation/filesystems/vfs.txt,
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.
Signed-off-by: Jens Axboe <ax...@kernel.dk>
Signed-off-by: Jaegeuk Kim <jaeg...@kernel.org>
---
fs/f2fs/data.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 8f931d699287..bc28ae5ae1ad 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -534,7 +534,7 @@ void f2fs_submit_page_write(struct f2fs_io_info *fio)
}
static struct bio *f2fs_grab_read_bio(struct inode *inode, block_t blkaddr,
- unsigned nr_pages)
+ unsigned nr_pages, unsigned op_flag)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
struct bio *bio;
@@ -546,7 +546,7 @@ static struct bio *f2fs_grab_read_bio(struct inode *inode,
block_t blkaddr,
return ERR_PTR(-ENOMEM);
f2fs_target_device(sbi, blkaddr, bio);
bio->bi_end_io = f2fs_read_end_io;
- bio_set_op_attrs(bio, REQ_OP_READ, 0);
+ bio_set_op_attrs(bio, REQ_OP_READ, op_flag);
if (f2fs_encrypted_file(inode))
post_read_steps |= 1 << STEP_DECRYPT;
@@ -571,7 +571,7 @@ static struct bio *f2fs_grab_read_bio(struct inode *inode,
block_t blkaddr,
static int f2fs_submit_page_read(struct inode *inode, struct page *page,
block_t blkaddr)
{
- struct bio *bio = f2fs_grab_read_bio(inode, blkaddr, 1);
+ struct bio *bio = f2fs_grab_read_bio(inode, blkaddr, 1, 0);
if (IS_ERR(bio))
return PTR_ERR(bio);
@@ -1421,10 +1421,15 @@ int f2fs_fiemap(struct inode *inode, struct
fiemap_extent_info *fieinfo,
/*
* This function was originally taken from fs/mpage.c, and customized for f2fs.
* Major change was from block_size == page_size in f2fs by default.
+ *
+ * Note that the aops->readpages() function is ONLY used for read-ahead. If
+ * this function ever deviates from doing just read-ahead, it should either
+ * use ->readpage() or do the necessary surgery to decouple ->readpages()
+ * from read-ahead.
*/
static int f2fs_mpage_readpages(struct address_space *mapping,
struct list_head *pages, struct page *page,
- unsigned nr_pages)
+ unsigned nr_pages, bool is_readahead)
{
struct bio *bio = NULL;
sector_t last_block_in_bio = 0;
@@ -1514,7 +1519,8 @@ static int f2fs_mpage_readpages(struct address_space
*mapping,
bio = NULL;
}
if (bio == NULL) {
- bio = f2fs_grab_read_bio(inode, block_nr, nr_pages);
+ bio = f2fs_grab_read_bio(inode, block_nr, nr_pages,
+ is_readahead ? REQ_RAHEAD : 0);
if (IS_ERR(bio)) {
bio = NULL;
goto set_error_page;
@@ -1558,7 +1564,7 @@ static int f2fs_read_data_page(struct file *file, struct
page *page)
if (f2fs_has_inline_data(inode))
ret = f2fs_read_inline_data(inode, page);
if (ret == -EAGAIN)
- ret = f2fs_mpage_readpages(page->mapping, NULL, page, 1);
+ ret = f2fs_mpage_readpages(page->mapping, NULL, page, 1, false);
return ret;
}
@@ -1575,7 +1581,7 @@ static int f2fs_read_data_pages(struct file *file,
if (f2fs_has_inline_data(inode))
return 0;
- return f2fs_mpage_readpages(mapping, pages, NULL, nr_pages);
+ return f2fs_mpage_readpages(mapping, pages, NULL, nr_pages, true);
}
static int encrypt_one_page(struct f2fs_io_info *fio)
--
2.17.0.441.gb46fe60e1d-goog
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