md: raid1-10: move raid1/raid10 common code into raid1-10.c

[mirror_ubuntu-bionic-kernel.git] / drivers / md / raid1-10.c

diff --git a/drivers/md/raid1-10.c b/drivers/md/raid1-10.c
index 3adb5b9dc4b4113b1c77c33265051e23d83bb2ed..9f2670b45f31ae8b99b09f33309bf31c6f704c7c 100644 (file)
--- a/drivers/md/raid1-10.c
+++ b/drivers/md/raid1-10.c
@@ -1,3 +1,65 @@
+/* Maximum size of each resync request */
+#define RESYNC_BLOCK_SIZE (64*1024)
+#define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE)
+
+/* for managing resync I/O pages */
+struct resync_pages {
+       void            *raid_bio;
+       struct page     *pages[RESYNC_PAGES];
+};
+
+static inline int resync_alloc_pages(struct resync_pages *rp,
+                                    gfp_t gfp_flags)
+{
+       int i;
+
+       for (i = 0; i < RESYNC_PAGES; i++) {
+               rp->pages[i] = alloc_page(gfp_flags);
+               if (!rp->pages[i])
+                       goto out_free;
+       }
+
+       return 0;
+
+out_free:
+       while (--i >= 0)
+               put_page(rp->pages[i]);
+       return -ENOMEM;
+}
+
+static inline void resync_free_pages(struct resync_pages *rp)
+{
+       int i;
+
+       for (i = 0; i < RESYNC_PAGES; i++)
+               put_page(rp->pages[i]);
+}
+
+static inline void resync_get_all_pages(struct resync_pages *rp)
+{
+       int i;
+
+       for (i = 0; i < RESYNC_PAGES; i++)
+               get_page(rp->pages[i]);
+}
+
+static inline struct page *resync_fetch_page(struct resync_pages *rp,
+                                            unsigned idx)
+{
+       if (WARN_ON_ONCE(idx >= RESYNC_PAGES))
+               return NULL;
+       return rp->pages[idx];
+}
+
+/*
+ * 'strct resync_pages' stores actual pages used for doing the resync
+ *  IO, and it is per-bio, so make .bi_private points to it.
+ */
+static inline struct resync_pages *get_resync_pages(struct bio *bio)
+{
+       return bio->bi_private;
+}
+
 /* generally called after bio_reset() for reseting bvec */
 static void md_bio_reset_resync_pages(struct bio *bio, struct resync_pages *rp,
                               int size)