[PATCH 6/6] mm: remove generic_writepages

Christoph Hellwig
2022-12-29T16:11:17Z

Now that all external callers are gone, just fold it into do_writepages.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
include/linux/writeback.h | 2 --
mm/page-writeback.c | 53 +++++++++++----------------------------
2 files changed, 15 insertions(+), 40 deletions(-)

diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index 06f9291b6fd512..2554b71765e9d0 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -369,8 +369,6 @@ bool wb_over_bg_thresh(struct bdi_writeback *wb);
typedef int (*writepage_t)(struct page *page, struct writeback_control *wbc,
void *data);

-int generic_writepages(struct address_space *mapping,
- struct writeback_control *wbc);
void tag_pages_for_writeback(struct address_space *mapping,
pgoff_t start, pgoff_t end);
int write_cache_pages(struct address_space *mapping,
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index ad608ef2a24365..dfeeceebba0ae0 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2526,12 +2526,8 @@ int write_cache_pages(struct address_space *mapping,
}
EXPORT_SYMBOL(write_cache_pages);

-/*
- * Function used by generic_writepages to call the real writepage
- * function and set the mapping flags on error
- */
-static int __writepage(struct page *page, struct writeback_control *wbc,
- void *data)
+static int writepage_cb(struct page *page, struct writeback_control *wbc,
+ void *data)
{
struct address_space *mapping = data;
int ret = mapping->a_ops->writepage(page, wbc);
@@ -2539,34 +2535,6 @@ static int __writepage(struct page *page, struct writeback_control *wbc,
return ret;
}

-/**
- * generic_writepages - walk the list of dirty pages of the given address space and writepage() all of them.
- * @mapping: address space structure to write
- * @wbc: subtract the number of written pages from *@wbc->nr_to_write
- *
- * This is a library function, which implements the writepages()
- * address_space_operation.
- *
- * Return: %0 on success, negative error code otherwise
- */
-int generic_writepages(struct address_space *mapping,
- struct writeback_control *wbc)
-{
- struct blk_plug plug;
- int ret;
-
- /* deal with chardevs and other special file */
- if (!mapping->a_ops->writepage)
- return 0;
-
- blk_start_plug(&plug);
- ret = write_cache_pages(mapping, wbc, __writepage, mapping);
- blk_finish_plug(&plug);
- return ret;
-}
-
-EXPORT_SYMBOL(generic_writepages);
-
int do_writepages(struct address_space *mapping, struct writeback_control *wbc)
{
int ret;
@@ -2577,11 +2545,20 @@ int do_writepages(struct address_space *mapping, struct writeback_control *wbc)
wb = inode_to_wb_wbc(mapping->host, wbc);
wb_bandwidth_estimate_start(wb);
while (1) {
- if (mapping->a_ops->writepages)
+ if (mapping->a_ops->writepages) {
ret = mapping->a_ops->writepages(mapping, wbc);
- else
- ret = generic_writepages(mapping, wbc);
- if ((ret != -ENOMEM) || (wbc->sync_mode != WB_SYNC_ALL))
+ } else if (mapping->a_ops->writepage) {
+ struct blk_plug plug;
+
+ blk_start_plug(&plug);
+ ret = write_cache_pages(mapping, wbc, writepage_cb,
+ mapping);
+ blk_finish_plug(&plug);
+ } else {
+ /* deal with chardevs and other special files */
+ ret = 0;
+ }
+ if (ret != -ENOMEM || wbc->sync_mode != WB_SYNC_ALL)
break;

/*
--
2.35.1