在 2021/12/13 1:05, Coly Li 写道:
From: Jianpeng Ma <jianpeng.ma@xxxxxxxxx>
This patch implements the bch_nvmpg_free_pages() of the buddy allocator.
The difference between this and page-buddy-free:
it need owner_uuid to free owner allocated pages, and must
persistent after free.
Signed-off-by: Jianpeng Ma <jianpeng.ma@xxxxxxxxx>
Co-developed-by: Qiaowei Ren <qiaowei.ren@xxxxxxxxx>
Signed-off-by: Qiaowei Ren <qiaowei.ren@xxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
---
drivers/md/bcache/nvmpg.c | 164 ++++++++++++++++++++++++++++++++++++--
drivers/md/bcache/nvmpg.h | 3 +
2 files changed, 160 insertions(+), 7 deletions(-)
diff --git a/drivers/md/bcache/nvmpg.c b/drivers/md/bcache/nvmpg.c
index a920779eb548..8ce0c4389b42 100644
--- a/drivers/md/bcache/nvmpg.c
+++ b/drivers/md/bcache/nvmpg.c
@@ -248,6 +248,57 @@ static int init_nvmpg_set_header(struct bch_nvmpg_ns *ns)
return rc;
}
+static void __free_space(struct bch_nvmpg_ns *ns, unsigned long nvmpg_offset,
+ int order)
+{
+ unsigned long add_pages = (1L << order);
+ pgoff_t pgoff;
+ struct page *page;
+ void *va;
+
+ if (nvmpg_offset == 0) {
+ pr_err("free pages on offset 0\n");
+ return;
+ }
+
+ page = bch_nvmpg_va_to_pg(bch_nvmpg_offset_to_ptr(nvmpg_offset));
+ WARN_ON((!page) || (page->private != order));
+ pgoff = page->index;
+
+ while (order < BCH_MAX_ORDER - 1) {
+ struct page *buddy_page;
+
+ pgoff_t buddy_pgoff = pgoff ^ (1L << order);
+ pgoff_t parent_pgoff = pgoff & ~(1L << order);
+
+ if ((parent_pgoff + (1L << (order + 1)) > ns->pages_total))
+ break;
+
+ va = bch_nvmpg_pgoff_to_ptr(ns, buddy_pgoff);
+ buddy_page = bch_nvmpg_va_to_pg(va);
+ WARN_ON(!buddy_page);
+
+ if (PageBuddy(buddy_page) && (buddy_page->private == order)) {
+ list_del((struct list_head *)&buddy_page->zone_device_data);
+ __ClearPageBuddy(buddy_page);
+ pgoff = parent_pgoff;
+ order++;
+ continue;
+ }
+ break;
+ }
+
+ va = bch_nvmpg_pgoff_to_ptr(ns, pgoff);
+ page = bch_nvmpg_va_to_pg(va);
+ WARN_ON(!page);
+ list_add((struct list_head *)&page->zone_device_data,
+ &ns->free_area[order]);
+ page->index = pgoff;
+ set_page_private(page, order);
+ __SetPageBuddy(page);
+ ns->free += add_pages;
+}
+
static void bch_nvmpg_init_free_space(struct bch_nvmpg_ns *ns)
{
unsigned int start, end, pages;
@@ -261,21 +312,19 @@ static void bch_nvmpg_init_free_space(struct bch_nvmpg_ns *ns)
pages = end - start;
while (pages) {
- void *addr;
-
for (i = BCH_MAX_ORDER - 1; i >= 0; i--) {
if ((pgoff_start % (1L << i) == 0) &&
(pages >= (1L << i)))
break;
}
- addr = bch_nvmpg_pgoff_to_ptr(ns, pgoff_start);
- page = bch_nvmpg_va_to_pg(addr);
+ page = bch_nvmpg_va_to_pg(
+ bch_nvmpg_pgoff_to_ptr(ns, pgoff_start));
set_page_private(page, i);
page->index = pgoff_start;
- __SetPageBuddy(page);
- list_add((struct list_head *)&page->zone_device_data,
- &ns->free_area[i]);
+
+ /* In order to update ns->free */
+ __free_space(ns, pgoff_start, i);
Hi,
While testing this patchset, we found that this is probably wrong,
pgoff_start represent page number here, however, __free_space expect
this to be page offset. Maybe this should be:
__free_space(ns, pgoff_start << PAGE_SHIFT, i);
Thanks,
Kuai
