On Fri, Jul 19, 2019 at 06:01:19PM +0200, David Hildenbrand wrote: > "host_page_base" is really confusing, let's make this clearer, also > rename the other offsets to indicate to which base they apply. > > offset -> mr_offset > ram_offset -> rb_offset > host_page_base -> rb_aligned_offset > > While at it, use QEMU_ALIGN_DOWN() instead of a handcrafted computation > and move the computation to the place where it is needed. > > Signed-off-by: David Hildenbrand <da...@redhat.com>
Acked-by: David Gibson <da...@gibson.dropbear.id.au>
> ---
> hw/virtio/virtio-balloon.c | 26 +++++++++++++-------------
> 1 file changed, 13 insertions(+), 13 deletions(-)
>
> diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
> index 287d5d4c97..29cee344b2 100644
> --- a/hw/virtio/virtio-balloon.c
> +++ b/hw/virtio/virtio-balloon.c
> @@ -47,24 +47,23 @@ static void virtio_balloon_reset_pbp(VirtIOBalloon
> *balloon)
> }
>
> static void balloon_inflate_page(VirtIOBalloon *balloon,
> - MemoryRegion *mr, hwaddr offset)
> + MemoryRegion *mr, hwaddr mr_offset)
> {
> - void *addr = memory_region_get_ram_ptr(mr) + offset;
> + void *addr = memory_region_get_ram_ptr(mr) + mr_offset;
> + ram_addr_t rb_offset, rb_aligned_offset;
> RAMBlock *rb;
> size_t rb_page_size;
> int subpages;
> - ram_addr_t ram_offset, host_page_base;
>
> /* XXX is there a better way to get to the RAMBlock than via a
> * host address? */
> - rb = qemu_ram_block_from_host(addr, false, &ram_offset);
> + rb = qemu_ram_block_from_host(addr, false, &rb_offset);
> rb_page_size = qemu_ram_pagesize(rb);
> - host_page_base = ram_offset & ~(rb_page_size - 1);
>
> if (rb_page_size == BALLOON_PAGE_SIZE) {
> /* Easy case */
>
> - ram_block_discard_range(rb, ram_offset, rb_page_size);
> + ram_block_discard_range(rb, rb_offset, rb_page_size);
> /* We ignore errors from ram_block_discard_range(), because it
> * has already reported them, and failing to discard a balloon
> * page is not fatal */
> @@ -80,11 +79,12 @@ static void balloon_inflate_page(VirtIOBalloon *balloon,
> warn_report_once(
> "Balloon used with backing page size > 4kiB, this may not be reliable");
>
> + rb_aligned_offset = QEMU_ALIGN_DOWN(rb_offset, rb_page_size);
> subpages = rb_page_size / BALLOON_PAGE_SIZE;
>
> if (balloon->pbp
> && (rb != balloon->pbp->rb
> - || host_page_base != balloon->pbp->base)) {
> + || rb_aligned_offset != balloon->pbp->base)) {
> /* We've partially ballooned part of a host page, but now
> * we're trying to balloon part of a different one. Too hard,
> * give up on the old partial page */
> @@ -96,10 +96,10 @@ static void balloon_inflate_page(VirtIOBalloon *balloon,
> size_t bitlen = BITS_TO_LONGS(subpages) * sizeof(unsigned long);
> balloon->pbp = g_malloc0(sizeof(PartiallyBalloonedPage) + bitlen);
> balloon->pbp->rb = rb;
> - balloon->pbp->base = host_page_base;
> + balloon->pbp->base = rb_aligned_offset;
> }
>
> - set_bit((ram_offset - balloon->pbp->base) / BALLOON_PAGE_SIZE,
> + set_bit((rb_offset - balloon->pbp->base) / BALLOON_PAGE_SIZE,
> balloon->pbp->bitmap);
>
> if (bitmap_full(balloon->pbp->bitmap, subpages)) {
> @@ -116,18 +116,18 @@ static void balloon_inflate_page(VirtIOBalloon *balloon,
> }
>
> static void balloon_deflate_page(VirtIOBalloon *balloon,
> - MemoryRegion *mr, hwaddr offset)
> + MemoryRegion *mr, hwaddr mr_offset)
> {
> - void *addr = memory_region_get_ram_ptr(mr) + offset;
> + void *addr = memory_region_get_ram_ptr(mr) + mr_offset;
> + ram_addr_t rb_offset;
> RAMBlock *rb;
> size_t rb_page_size;
> - ram_addr_t ram_offset;
> void *host_addr;
> int ret;
>
> /* XXX is there a better way to get to the RAMBlock than via a
> * host address? */
> - rb = qemu_ram_block_from_host(addr, false, &ram_offset);
> + rb = qemu_ram_block_from_host(addr, false, &rb_offset);
> rb_page_size = qemu_ram_pagesize(rb);
>
> if (balloon->pbp) {
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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