diff options
author | Peter Maydell <peter.maydell@linaro.org> | 2019-03-04 11:04:31 +0000 |
---|---|---|
committer | Peter Maydell <peter.maydell@linaro.org> | 2019-03-04 11:04:31 +0000 |
commit | 1d31f1872b337e4acac5bf6b3c2a45b66e43b494 (patch) | |
tree | b1c71f789d14aee7d170af69fab5a7a8b817c1a3 /hw/virtio/virtio-balloon.c | |
parent | 20b084c4b1401b7f8fbc385649d48c67b6f43d44 (diff) | |
parent | 88c869198aa630e0477d653d0abf3f42c7c44d1f (diff) |
Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging
pci, pc, virtio: fixes, cleanups, tests
Lots of work on tests: BiosTablesTest UEFI app,
vhost-user testing for non-Linux hosts.
Misc cleanups and fixes all over the place
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
# gpg: Signature made Fri 22 Feb 2019 15:51:40 GMT
# gpg: using RSA key 281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17 0970 C350 3912 AFBE 8E67
# Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA 8A0D 281F 0DB8 D28D 5469
* remotes/mst/tags/for_upstream: (26 commits)
pci: Sanity test minimum downstream LNKSTA
hw/smbios: fix offset of type 3 sku field
pci: Move NVIDIA vendor id to the rest of ids
virtio-balloon: Safely handle BALLOON_PAGE_SIZE < host page size
virtio-balloon: Use ram_block_discard_range() instead of raw madvise()
virtio-balloon: Rework ballon_page() interface
virtio-balloon: Corrections to address verification
virtio-balloon: Remove unnecessary MADV_WILLNEED on deflate
i386/kvm: ignore masked irqs when update msi routes
contrib/vhost-user-blk: fix the compilation issue
Revert "contrib/vhost-user-blk: fix the compilation issue"
pc-dimm: use same mechanism for [get|set]_addr
tests/data: introduce "uefi-boot-images" with the "bios-tables-test" ISOs
tests/uefi-test-tools: add build scripts
tests: introduce "uefi-test-tools" with the BiosTablesTest UEFI app
roms: build the EfiRom utility from the roms/edk2 submodule
roms: add the edk2 project as a git submodule
vhost-user-test: create a temporary directory per TestServer
vhost-user-test: small changes to init_hugepagefs
vhost-user-test: create a main loop per TestServer
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'hw/virtio/virtio-balloon.c')
-rw-r--r-- | hw/virtio/virtio-balloon.c | 102 |
1 files changed, 86 insertions, 16 deletions
diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index a12677d4d5..d3f2913a85 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -33,11 +33,81 @@ #define BALLOON_PAGE_SIZE (1 << VIRTIO_BALLOON_PFN_SHIFT) -static void balloon_page(void *addr, int deflate) +struct PartiallyBalloonedPage { + RAMBlock *rb; + ram_addr_t base; + unsigned long bitmap[]; +}; + +static void balloon_inflate_page(VirtIOBalloon *balloon, + MemoryRegion *mr, hwaddr offset) { - if (!qemu_balloon_is_inhibited()) { - qemu_madvise(addr, BALLOON_PAGE_SIZE, - deflate ? QEMU_MADV_WILLNEED : QEMU_MADV_DONTNEED); + void *addr = memory_region_get_ram_ptr(mr) + 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_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); + /* We ignore errors from ram_block_discard_range(), because it + * has already reported them, and failing to discard a balloon + * page is not fatal */ + return; + } + + /* Hard case + * + * We've put a piece of a larger host page into the balloon - we + * need to keep track until we have a whole host page to + * discard + */ + warn_report_once( +"Balloon used with backing page size > 4kiB, this may not be reliable"); + + subpages = rb_page_size / BALLOON_PAGE_SIZE; + + if (balloon->pbp + && (rb != balloon->pbp->rb + || host_page_base != 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 */ + free(balloon->pbp); + balloon->pbp = NULL; + } + + if (!balloon->pbp) { + /* Starting on a new host page */ + 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; + } + + bitmap_set(balloon->pbp->bitmap, + (ram_offset - balloon->pbp->base) / BALLOON_PAGE_SIZE, + subpages); + + if (bitmap_full(balloon->pbp->bitmap, subpages)) { + /* We've accumulated a full host page, we can actually discard + * it now */ + + ram_block_discard_range(rb, balloon->pbp->base, 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 */ + + free(balloon->pbp); + balloon->pbp = NULL; } } @@ -222,17 +292,19 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) } while (iov_to_buf(elem->out_sg, elem->out_num, offset, &pfn, 4) == 4) { - ram_addr_t pa; - ram_addr_t addr; + hwaddr pa; int p = virtio_ldl_p(vdev, &pfn); - pa = (ram_addr_t) p << VIRTIO_BALLOON_PFN_SHIFT; + pa = (hwaddr) p << VIRTIO_BALLOON_PFN_SHIFT; offset += 4; - /* FIXME: remove get_system_memory(), but how? */ - section = memory_region_find(get_system_memory(), pa, 1); - if (!int128_nz(section.size) || - !memory_region_is_ram(section.mr) || + section = memory_region_find(get_system_memory(), pa, + BALLOON_PAGE_SIZE); + if (!section.mr) { + trace_virtio_balloon_bad_addr(pa); + continue; + } + if (!memory_region_is_ram(section.mr) || memory_region_is_rom(section.mr) || memory_region_is_romd(section.mr)) { trace_virtio_balloon_bad_addr(pa); @@ -242,11 +314,9 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) trace_virtio_balloon_handle_output(memory_region_name(section.mr), pa); - /* Using memory_region_get_ram_ptr is bending the rules a bit, but - should be OK because we only want a single page. */ - addr = section.offset_within_region; - balloon_page(memory_region_get_ram_ptr(section.mr) + addr, - !!(vq == s->dvq)); + if (!qemu_balloon_is_inhibited() && vq != s->dvq) { + balloon_inflate_page(s, section.mr, section.offset_within_region); + } memory_region_unref(section.mr); } |