[PATCH v1 12/29] virtio-mem: factor out fake-offlining into virtio_mem_fake_offline()

From: David Hildenbrand
Date: Mon Oct 12 2020 - 08:55:24 EST


... which now matches virtio_mem_fake_online(). We'll reuse this
functionality soon.

Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx>
Cc: Jason Wang <jasowang@xxxxxxxxxx>
Cc: Pankaj Gupta <pankaj.gupta.linux@xxxxxxxxx>
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
---
drivers/virtio/virtio_mem.c | 34 ++++++++++++++++++++++++----------
1 file changed, 24 insertions(+), 10 deletions(-)

diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c
index 00d1cfca4713..d132bc54ef57 100644
--- a/drivers/virtio/virtio_mem.c
+++ b/drivers/virtio/virtio_mem.c
@@ -832,6 +832,27 @@ static void virtio_mem_fake_online(unsigned long pfn, unsigned long nr_pages)
}
}

+/*
+ * Try to allocate a range, marking pages fake-offline, effectively
+ * fake-offlining them.
+ */
+static int virtio_mem_fake_offline(unsigned long pfn, unsigned long nr_pages)
+{
+ int rc;
+
+ rc = alloc_contig_range(pfn, pfn + nr_pages, MIGRATE_MOVABLE,
+ GFP_KERNEL);
+ if (rc == -ENOMEM)
+ /* whoops, out of memory */
+ return rc;
+ if (rc)
+ return -EBUSY;
+
+ virtio_mem_set_fake_offline(pfn, nr_pages, true);
+ adjust_managed_page_count(pfn_to_page(pfn), -nr_pages);
+ return 0;
+}
+
static void virtio_mem_online_page_cb(struct page *page, unsigned int order)
{
const unsigned long addr = page_to_phys(page);
@@ -1335,17 +1356,10 @@ static int virtio_mem_mb_unplug_sb_online(struct virtio_mem *vm,

start_pfn = PFN_DOWN(virtio_mem_mb_id_to_phys(mb_id) +
sb_id * vm->subblock_size);
- rc = alloc_contig_range(start_pfn, start_pfn + nr_pages,
- MIGRATE_MOVABLE, GFP_KERNEL);
- if (rc == -ENOMEM)
- /* whoops, out of memory */
- return rc;
- if (rc)
- return -EBUSY;

- /* Mark it as fake-offline before unplugging it */
- virtio_mem_set_fake_offline(start_pfn, nr_pages, true);
- adjust_managed_page_count(pfn_to_page(start_pfn), -nr_pages);
+ rc = virtio_mem_fake_offline(start_pfn, nr_pages);
+ if (rc)
+ return rc;

/* Try to unplug the allocated memory */
rc = virtio_mem_mb_unplug_sb(vm, mb_id, sb_id, count);
--
2.26.2