1 files changed, 52 insertions, 98 deletions

diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c
index 1aa29f8fdfe1..426c97aef900 100644
--- a/drivers/block/drbd/drbd_bitmap.c
+++ b/drivers/block/drbd/drbd_bitmap.c
@@ -22,6 +22,8 @@
    the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
 #include <linux/bitops.h>
 #include <linux/vmalloc.h>
 #include <linux/string.h>
@@ -353,9 +355,8 @@ static void bm_free_pages(struct page **pages, unsigned long number)
 
 	for (i = 0; i < number; i++) {
 		if (!pages[i]) {
-			printk(KERN_ALERT "drbd: bm_free_pages tried to free "
-					  "a NULL pointer; i=%lu n=%lu\n",
-					  i, number);
+			pr_alert("bm_free_pages tried to free a NULL pointer; i=%lu n=%lu\n",
+				 i, number);
 			continue;
 		}
 		__free_page(pages[i]);
@@ -592,7 +593,7 @@ static void bm_memset(struct drbd_bitmap *b, size_t offset, int c, size_t len)
 	end = offset + len;
 
 	if (end > b->bm_words) {
-		printk(KERN_ALERT "drbd: bm_memset end > bm_words\n");
+		pr_alert("bm_memset end > bm_words\n");
 		return;
 	}
 
@@ -602,7 +603,7 @@ static void bm_memset(struct drbd_bitmap *b, size_t offset, int c, size_t len)
 		p_addr = bm_map_pidx(b, idx);
 		bm = p_addr + MLPP(offset);
 		if (bm+do_now > p_addr + LWPP) {
-			printk(KERN_ALERT "drbd: BUG BUG BUG! p_addr:%p bm:%p do_now:%d\n",
+			pr_alert("BUG BUG BUG! p_addr:%p bm:%p do_now:%d\n",
 			       p_addr, bm, (int)do_now);
 		} else
 			memset(bm, c, do_now * sizeof(long));
@@ -927,22 +928,14 @@ void drbd_bm_clear_all(struct drbd_device *device)
 	spin_unlock_irq(&b->bm_lock);
 }
 
-struct bm_aio_ctx {
-	struct drbd_device *device;
-	atomic_t in_flight;
-	unsigned int done;
-	unsigned flags;
-#define BM_AIO_COPY_PAGES	1
-#define BM_AIO_WRITE_HINTED	2
-#define BM_WRITE_ALL_PAGES	4
-	int error;
-	struct kref kref;
-};
-
-static void bm_aio_ctx_destroy(struct kref *kref)
+static void drbd_bm_aio_ctx_destroy(struct kref *kref)
 {
-	struct bm_aio_ctx *ctx = container_of(kref, struct bm_aio_ctx, kref);
+	struct drbd_bm_aio_ctx *ctx = container_of(kref, struct drbd_bm_aio_ctx, kref);
+	unsigned long flags;
 
+	spin_lock_irqsave(&ctx->device->resource->req_lock, flags);
+	list_del(&ctx->list);
+	spin_unlock_irqrestore(&ctx->device->resource->req_lock, flags);
 	put_ldev(ctx->device);
 	kfree(ctx);
 }
@@ -950,7 +943,7 @@ static void bm_aio_ctx_destroy(struct kref *kref)
 /* bv_page may be a copy, or may be the original */
 static void bm_async_io_complete(struct bio *bio, int error)
 {
-	struct bm_aio_ctx *ctx = bio->bi_private;
+	struct drbd_bm_aio_ctx *ctx = bio->bi_private;
 	struct drbd_device *device = ctx->device;
 	struct drbd_bitmap *b = device->bitmap;
 	unsigned int idx = bm_page_to_idx(bio->bi_io_vec[0].bv_page);
@@ -993,17 +986,18 @@ static void bm_async_io_complete(struct bio *bio, int error)
 	if (atomic_dec_and_test(&ctx->in_flight)) {
 		ctx->done = 1;
 		wake_up(&device->misc_wait);
-		kref_put(&ctx->kref, &bm_aio_ctx_destroy);
+		kref_put(&ctx->kref, &drbd_bm_aio_ctx_destroy);
 	}
 }
 
-static void bm_page_io_async(struct bm_aio_ctx *ctx, int page_nr, int rw) __must_hold(local)
+static void bm_page_io_async(struct drbd_bm_aio_ctx *ctx, int page_nr) __must_hold(local)
 {
 	struct bio *bio = bio_alloc_drbd(GFP_NOIO);
 	struct drbd_device *device = ctx->device;
 	struct drbd_bitmap *b = device->bitmap;
 	struct page *page;
 	unsigned int len;
+	unsigned int rw = (ctx->flags & BM_AIO_READ) ? READ : WRITE;
 
 	sector_t on_disk_sector =
 		device->ldev->md.md_offset + device->ldev->md.bm_offset;
@@ -1049,9 +1043,9 @@ static void bm_page_io_async(struct bm_aio_ctx *ctx, int page_nr, int rw) __must
 /*
  * bm_rw: read/write the whole bitmap from/to its on disk location.
  */
-static int bm_rw(struct drbd_device *device, int rw, unsigned flags, unsigned lazy_writeout_upper_idx) __must_hold(local)
+static int bm_rw(struct drbd_device *device, const unsigned int flags, unsigned lazy_writeout_upper_idx) __must_hold(local)
 {
-	struct bm_aio_ctx *ctx;
+	struct drbd_bm_aio_ctx *ctx;
 	struct drbd_bitmap *b = device->bitmap;
 	int num_pages, i, count = 0;
 	unsigned long now;
@@ -1067,12 +1061,13 @@ static int bm_rw(struct drbd_device *device, int rw, unsigned flags, unsigned la
 	 * as we submit copies of pages anyways.
 	 */
 
-	ctx = kmalloc(sizeof(struct bm_aio_ctx), GFP_NOIO);
+	ctx = kmalloc(sizeof(struct drbd_bm_aio_ctx), GFP_NOIO);
 	if (!ctx)
 		return -ENOMEM;
 
-	*ctx = (struct bm_aio_ctx) {
+	*ctx = (struct drbd_bm_aio_ctx) {
 		.device = device,
+		.start_jif = jiffies,
 		.in_flight = ATOMIC_INIT(1),
 		.done = 0,
 		.flags = flags,
@@ -1080,15 +1075,21 @@ static int bm_rw(struct drbd_device *device, int rw, unsigned flags, unsigned la
 		.kref = { ATOMIC_INIT(2) },
 	};
 
-	if (!get_ldev_if_state(device, D_ATTACHING)) {  /* put is in bm_aio_ctx_destroy() */
+	if (!get_ldev_if_state(device, D_ATTACHING)) {  /* put is in drbd_bm_aio_ctx_destroy() */
 		drbd_err(device, "ASSERT FAILED: get_ldev_if_state() == 1 in bm_rw()\n");
 		kfree(ctx);
 		return -ENODEV;
 	}
+	/* Here D_ATTACHING is sufficient since drbd_bm_read() is called only from
+	   drbd_adm_attach(), after device->ldev was assigned. */
 
-	if (!ctx->flags)
+	if (0 == (ctx->flags & ~BM_AIO_READ))
 		WARN_ON(!(BM_LOCKED_MASK & b->bm_flags));
 
+	spin_lock_irq(&device->resource->req_lock);
+	list_add_tail(&ctx->list, &device->pending_bitmap_io);
+	spin_unlock_irq(&device->resource->req_lock);
+
 	num_pages = b->bm_number_of_pages;
 
 	now = jiffies;
@@ -1098,13 +1099,13 @@ static int bm_rw(struct drbd_device *device, int rw, unsigned flags, unsigned la
 		/* ignore completely unchanged pages */
 		if (lazy_writeout_upper_idx && i == lazy_writeout_upper_idx)
 			break;
-		if (rw & WRITE) {
+		if (!(flags & BM_AIO_READ)) {
 			if ((flags & BM_AIO_WRITE_HINTED) &&
 			    !test_and_clear_bit(BM_PAGE_HINT_WRITEOUT,
 				    &page_private(b->bm_pages[i])))
 				continue;
 
-			if (!(flags & BM_WRITE_ALL_PAGES) &&
+			if (!(flags & BM_AIO_WRITE_ALL_PAGES) &&
 			    bm_test_page_unchanged(b->bm_pages[i])) {
 				dynamic_drbd_dbg(device, "skipped bm write for idx %u\n", i);
 				continue;
@@ -1118,7 +1119,7 @@ static int bm_rw(struct drbd_device *device, int rw, unsigned flags, unsigned la
 			}
 		}
 		atomic_inc(&ctx->in_flight);
-		bm_page_io_async(ctx, i, rw);
+		bm_page_io_async(ctx, i);
 		++count;
 		cond_resched();
 	}
@@ -1134,12 +1135,12 @@ static int bm_rw(struct drbd_device *device, int rw, unsigned flags, unsigned la
 	if (!atomic_dec_and_test(&ctx->in_flight))
 		wait_until_done_or_force_detached(device, device->ldev, &ctx->done);
 	else
-		kref_put(&ctx->kref, &bm_aio_ctx_destroy);
+		kref_put(&ctx->kref, &drbd_bm_aio_ctx_destroy);
 
 	/* summary for global bitmap IO */
 	if (flags == 0)
 		drbd_info(device, "bitmap %s of %u pages took %lu jiffies\n",
-			 rw == WRITE ? "WRITE" : "READ",
+			 (flags & BM_AIO_READ) ? "READ" : "WRITE",
 			 count, jiffies - now);
 
 	if (ctx->error) {
@@ -1152,20 +1153,18 @@ static int bm_rw(struct drbd_device *device, int rw, unsigned flags, unsigned la
 		err = -EIO; /* Disk timeout/force-detach during IO... */
 
 	now = jiffies;
-	if (rw == WRITE) {
-		drbd_md_flush(device);
-	} else /* rw == READ */ {
+	if (flags & BM_AIO_READ) {
 		b->bm_set = bm_count_bits(b);
 		drbd_info(device, "recounting of set bits took additional %lu jiffies\n",
 		     jiffies - now);
 	}
 	now = b->bm_set;
 
-	if (flags == 0)
+	if ((flags & ~BM_AIO_READ) == 0)
 		drbd_info(device, "%s (%lu bits) marked out-of-sync by on disk bit-map.\n",
 		     ppsize(ppb, now << (BM_BLOCK_SHIFT-10)), now);
 
-	kref_put(&ctx->kref, &bm_aio_ctx_destroy);
+	kref_put(&ctx->kref, &drbd_bm_aio_ctx_destroy);
 	return err;
 }
 
@@ -1175,7 +1174,7 @@ static int bm_rw(struct drbd_device *device, int rw, unsigned flags, unsigned la
  */
 int drbd_bm_read(struct drbd_device *device) __must_hold(local)
 {
-	return bm_rw(device, READ, 0, 0);
+	return bm_rw(device, BM_AIO_READ, 0);
 }
 
 /**
@@ -1186,7 +1185,7 @@ int drbd_bm_read(struct drbd_device *device) __must_hold(local)
  */
 int drbd_bm_write(struct drbd_device *device) __must_hold(local)
 {
-	return bm_rw(device, WRITE, 0, 0);
+	return bm_rw(device, 0, 0);
 }
 
 /**
@@ -1197,7 +1196,17 @@ int drbd_bm_write(struct drbd_device *device) __must_hold(local)
  */
 int drbd_bm_write_all(struct drbd_device *device) __must_hold(local)
 {
-	return bm_rw(device, WRITE, BM_WRITE_ALL_PAGES, 0);
+	return bm_rw(device, BM_AIO_WRITE_ALL_PAGES, 0);
+}
+
+/**
+ * drbd_bm_write_lazy() - Write bitmap pages 0 to @upper_idx-1, if they have changed.
+ * @device:	DRBD device.
+ * @upper_idx:	0: write all changed pages; +ve: page index to stop scanning for changed pages
+ */
+int drbd_bm_write_lazy(struct drbd_device *device, unsigned upper_idx) __must_hold(local)
+{
+	return bm_rw(device, BM_AIO_COPY_PAGES, upper_idx);
 }
 
 /**
@@ -1213,7 +1222,7 @@ int drbd_bm_write_all(struct drbd_device *device) __must_hold(local)
  */
 int drbd_bm_write_copy_pages(struct drbd_device *device) __must_hold(local)
 {
-	return bm_rw(device, WRITE, BM_AIO_COPY_PAGES, 0);
+	return bm_rw(device, BM_AIO_COPY_PAGES, 0);
 }
 
 /**
@@ -1222,62 +1231,7 @@ int drbd_bm_write_copy_pages(struct drbd_device *device) __must_hold(local)
  */
 int drbd_bm_write_hinted(struct drbd_device *device) __must_hold(local)
 {
-	return bm_rw(device, WRITE, BM_AIO_WRITE_HINTED | BM_AIO_COPY_PAGES, 0);
-}
-
-/**
- * drbd_bm_write_page() - Writes a PAGE_SIZE aligned piece of bitmap
- * @device:	DRBD device.
- * @idx:	bitmap page index
- *
- * We don't want to special case on logical_block_size of the backend device,
- * so we submit PAGE_SIZE aligned pieces.
- * Note that on "most" systems, PAGE_SIZE is 4k.
- *
- * In case this becomes an issue on systems with larger PAGE_SIZE,
- * we may want to change this again to write 4k aligned 4k pieces.
- */
-int drbd_bm_write_page(struct drbd_device *device, unsigned int idx) __must_hold(local)
-{
-	struct bm_aio_ctx *ctx;
-	int err;
-
-	if (bm_test_page_unchanged(device->bitmap->bm_pages[idx])) {
-		dynamic_drbd_dbg(device, "skipped bm page write for idx %u\n", idx);
-		return 0;
-	}
-
-	ctx = kmalloc(sizeof(struct bm_aio_ctx), GFP_NOIO);
-	if (!ctx)
-		return -ENOMEM;
-
-	*ctx = (struct bm_aio_ctx) {
-		.device = device,
-		.in_flight = ATOMIC_INIT(1),
-		.done = 0,
-		.flags = BM_AIO_COPY_PAGES,
-		.error = 0,
-		.kref = { ATOMIC_INIT(2) },
-	};
-
-	if (!get_ldev_if_state(device, D_ATTACHING)) {  /* put is in bm_aio_ctx_destroy() */
-		drbd_err(device, "ASSERT FAILED: get_ldev_if_state() == 1 in drbd_bm_write_page()\n");
-		kfree(ctx);
-		return -ENODEV;
-	}
-
-	bm_page_io_async(ctx, idx, WRITE_SYNC);
-	wait_until_done_or_force_detached(device, device->ldev, &ctx->done);
-
-	if (ctx->error)
-		drbd_chk_io_error(device, 1, DRBD_META_IO_ERROR);
-		/* that causes us to detach, so the in memory bitmap will be
-		 * gone in a moment as well. */
-
-	device->bm_writ_cnt++;
-	err = atomic_read(&ctx->in_flight) ? -EIO : ctx->error;
-	kref_put(&ctx->kref, &bm_aio_ctx_destroy);
-	return err;
+	return bm_rw(device, BM_AIO_WRITE_HINTED | BM_AIO_COPY_PAGES, 0);
 }
 
 /* NOTE