Re: [PATCH RFC md-6.16 v3 11/19] md/md-llbitmap: implement bitmap IO

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi,

在 2025/05/12 13:15, Christoph Hellwig 写道:
On Mon, May 12, 2025 at 09:19:19AM +0800, Yu Kuai wrote:
+static bool is_raid456(struct mddev *mddev)
+{
+	return (mddev->level == 4 || mddev->level == 5 || mddev->level == 6);
+}

This really should be in a common helper somewhere..

Perhaps md.h?

+static int llbitmap_read(struct llbitmap *llbitmap, enum llbitmap_state *state,
+			 loff_t pos)
+{
+	pos += BITMAP_SB_SIZE;
+	*state = llbitmap->barrier[pos >> PAGE_SHIFT].data[offset_in_page(pos)];
+	return 0;
+}

This always return 0, and could just return void.

Ok

+static void llbitmap_set_page_dirty(struct llbitmap *llbitmap, int idx, int offset)

Overly long line.

Also should the second and third argument be unsigned?

Ok

+	/*
+	 * if the bit is already dirty, or other page bytes is the same bit is
+	 * already BitDirty, then mark the whole bytes in the bit as dirty
+	 */
+	if (test_and_set_bit(bit, barrier->dirty)) {
+		infectious = true;
+	} else {
+		for (pos = bit * io_size; pos < (bit + 1) * io_size - 1;
+		     pos++) {
+			if (pos == offset)
+				continue;
+			if (barrier->data[pos] == BitDirty ||
+			    barrier->data[pos] == BitNeedSync) {
+				infectious = true;
+				break;
+			}
+		}
+
+	}
+	if (!infectious)
+		return;

Mabe use a goto and/or a helper function containing the for loop to
clean up the control flow here a bit?

Ok, I;ll add a helper function.

+static int llbitmap_write(struct llbitmap *llbitmap, enum llbitmap_state state,
+			  loff_t pos)
+{
+	int idx;
+	int offset;

Unsigned?

+
+	pos += BITMAP_SB_SIZE;
+	idx = pos >> PAGE_SHIFT;
+	offset = offset_in_page(pos);
+
+	llbitmap->barrier[idx].data[offset] = state;
+	if (state == BitDirty || state == BitNeedSync)
+		llbitmap_set_page_dirty(llbitmap, idx, offset);
+	return 0;

and this could also be a void return.

Ok.

+		sector = mddev->bitmap_info.offset + (idx << PAGE_SECTORS_SHIFT);

Overly long line.

+			if (rdev->raid_disk < 0 || test_bit(Faulty, &rdev->flags))

Same here.

+	int nr_pages = (llbitmap->chunks + BITMAP_SB_SIZE + PAGE_SIZE - 1) / PAGE_SIZE;

Unsigned for the type, and DIV_ROUND_UP for the calculation.

Ok.

+	struct page *page;
+	int i = 0;
+
+	llbitmap->nr_pages = nr_pages;
+	while (i < nr_pages) {
+		page = llbitmap_read_page(llbitmap, i);
+		if (IS_ERR(page)) {
+			llbitmap_free_pages(llbitmap);
+			return PTR_ERR(page);
+		}
+
+		if (percpu_ref_init(&llbitmap->barrier[i].active, active_release,
+				    PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) {
+			__free_page(page);
+			return -ENOMEM;

Doesn't this also need a llbitmap_free_pages for the error case?

Of course, my bad that I forgot this.

Thanks again for the review!
Kuai


.






[Index of Archives]     [DM Crypt]     [Fedora Desktop]     [ATA RAID]     [Fedora Marketing]     [Fedora Packaging]     [Fedora SELinux]     [Yosemite Discussion]     [KDE Users]     [Fedora Docs]

  Powered by Linux