The patch titled
Subject: fuse: convert from readpages to readahead
has been added to the -mm tree. Its filename is
fuse-convert-from-readpages-to-readahead.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/fuse-convert-from-readpages-to-readahead.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/fuse-convert-from-readpages-to-readahead.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: fuse: convert from readpages to readahead
Implement the new readahead operation in fuse by using __readahead_batch()
to fill the array of pages in fuse_args_pages directly. This lets us
inline fuse_readpages_fill() into fuse_readahead().
Link: http://lkml.kernel.org/r/20200414150233.24495-25-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Dave Chinner <dchinner@xxxxxxxxxx>
Reviewed-by: William Kucharski <william.kucharski@xxxxxxxxxx>
Cc: Chao Yu <yuchao0@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Cong Wang <xiyou.wangcong@xxxxxxxxx>
Cc: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Cc: Eric Biggers <ebiggers@xxxxxxxxxx>
Cc: Gao Xiang <gaoxiang25@xxxxxxxxxx>
Cc: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Cc: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx>
Cc: Junxiao Bi <junxiao.bi@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Zi Yan <ziy@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/fuse/file.c | 99 ++++++++++++-----------------------------------
1 file changed, 27 insertions(+), 72 deletions(-)
--- a/fs/fuse/file.c~fuse-convert-from-readpages-to-readahead
+++ a/fs/fuse/file.c
@@ -915,84 +915,39 @@ static void fuse_send_readpages(struct f
fuse_readpages_end(fc, &ap->args, err);
}
-struct fuse_fill_data {
- struct fuse_io_args *ia;
- struct file *file;
- struct inode *inode;
- unsigned int nr_pages;
- unsigned int max_pages;
-};
-
-static int fuse_readpages_fill(void *_data, struct page *page)
+static void fuse_readahead(struct readahead_control *rac)
{
- struct fuse_fill_data *data = _data;
- struct fuse_io_args *ia = data->ia;
- struct fuse_args_pages *ap = &ia->ap;
- struct inode *inode = data->inode;
+ struct inode *inode = rac->mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
+ unsigned int i, max_pages, nr_pages = 0;
- fuse_wait_on_page_writeback(inode, page->index);
-
- if (ap->num_pages &&
- (ap->num_pages == fc->max_pages ||
- (ap->num_pages + 1) * PAGE_SIZE > fc->max_read ||
- ap->pages[ap->num_pages - 1]->index + 1 != page->index)) {
- data->max_pages = min_t(unsigned int, data->nr_pages,
- fc->max_pages);
- fuse_send_readpages(ia, data->file);
- data->ia = ia = fuse_io_alloc(NULL, data->max_pages);
- if (!ia) {
- unlock_page(page);
- return -ENOMEM;
- }
- ap = &ia->ap;
- }
-
- if (WARN_ON(ap->num_pages >= data->max_pages)) {
- unlock_page(page);
- fuse_io_free(ia);
- return -EIO;
- }
-
- get_page(page);
- ap->pages[ap->num_pages] = page;
- ap->descs[ap->num_pages].length = PAGE_SIZE;
- ap->num_pages++;
- data->nr_pages--;
- return 0;
-}
-
-static int fuse_readpages(struct file *file, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages)
-{
- struct inode *inode = mapping->host;
- struct fuse_conn *fc = get_fuse_conn(inode);
- struct fuse_fill_data data;
- int err;
-
- err = -EIO;
if (is_bad_inode(inode))
- goto out;
+ return;
- data.file = file;
- data.inode = inode;
- data.nr_pages = nr_pages;
- data.max_pages = min_t(unsigned int, nr_pages, fc->max_pages);
-;
- data.ia = fuse_io_alloc(NULL, data.max_pages);
- err = -ENOMEM;
- if (!data.ia)
- goto out;
+ max_pages = min(fc->max_pages, fc->max_read / PAGE_SIZE);
- err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
- if (!err) {
- if (data.ia->ap.num_pages)
- fuse_send_readpages(data.ia, file);
- else
- fuse_io_free(data.ia);
+ for (;;) {
+ struct fuse_io_args *ia;
+ struct fuse_args_pages *ap;
+
+ nr_pages = readahead_count(rac) - nr_pages;
+ if (nr_pages > max_pages)
+ nr_pages = max_pages;
+ if (nr_pages == 0)
+ break;
+ ia = fuse_io_alloc(NULL, nr_pages);
+ if (!ia)
+ return;
+ ap = &ia->ap;
+ nr_pages = __readahead_batch(rac, ap->pages, nr_pages);
+ for (i = 0; i < nr_pages; i++) {
+ fuse_wait_on_page_writeback(inode,
+ readahead_index(rac) + i);
+ ap->descs[i].length = PAGE_SIZE;
+ }
+ ap->num_pages = nr_pages;
+ fuse_send_readpages(ia, rac->file);
}
-out:
- return err;
}
static ssize_t fuse_cache_read_iter(struct kiocb *iocb, struct iov_iter *to)
@@ -3373,10 +3328,10 @@ static const struct file_operations fuse
static const struct address_space_operations fuse_file_aops = {
.readpage = fuse_readpage,
+ .readahead = fuse_readahead,
.writepage = fuse_writepage,
.writepages = fuse_writepages,
.launder_page = fuse_launder_page,
- .readpages = fuse_readpages,
.set_page_dirty = __set_page_dirty_nobuffers,
.bmap = fuse_bmap,
.direct_IO = fuse_direct_IO,
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-move-readahead-prototypes-from-mmh.patch
mm-return-void-from-various-readahead-functions.patch
mm-ignore-return-value-of-readpages.patch
mm-move-readahead-nr_pages-check-into-read_pages.patch
mm-add-new-readahead_control-api.patch
mm-use-readahead_control-to-pass-arguments.patch
mm-rename-various-offset-parameters-to-index.patch
mm-rename-readahead-loop-variable-to-i.patch
mm-remove-page_offset-from-readahead-loop.patch
mm-put-readahead-pages-in-cache-earlier.patch
mm-add-readahead-address-space-operation.patch
mm-move-end_index-check-out-of-readahead-loop.patch
mm-add-page_cache_readahead_unbounded.patch
mm-document-why-we-dont-set-pagereadahead.patch
mm-use-memalloc_nofs_save-in-readahead-path.patch
fs-convert-mpage_readpages-to-mpage_readahead.patch
btrfs-convert-from-readpages-to-readahead.patch
erofs-convert-uncompressed-files-from-readpages-to-readahead.patch
erofs-convert-compressed-files-from-readpages-to-readahead.patch
ext4-convert-from-readpages-to-readahead.patch
ext4-pass-the-inode-to-ext4_mpage_readpages.patch
f2fs-convert-from-readpages-to-readahead.patch
f2fs-pass-the-inode-to-f2fs_mpage_readpages.patch
fuse-convert-from-readpages-to-readahead.patch
iomap-convert-from-readpages-to-readahead.patch
