This patchset fixes the migration of storage attributes. Each memory slot has a bitmap, with 2 bits per page, used to keep track of dirty pages during migration. We only use one bit, the other would be wasted. With this patch, the second bit is now used to keep track of dirty storage attributes. This means that we do not need anymore to allocate and manage the additional bitmap, and no extra work is needed to keep track of memory slots. The code does get a little bit more complicated when accounting for the memory slots, but overall it should be more robust. The first patch simply introduces two auxiliary functions, while the second patch does the actual job. v4 -> v5 * rebased on v4.17-rc3 v3 -> v4 * move gfn_to_memslot_approx to the second patch * rename kvm_shadow_dirty_bitmap to kvm_second_dirty_bitmap * removed useless (un)likely() * fixed and improved some comments * replaced break with return in kvm_s390_get_cmma * pass *slots instead of *kvm in a few functions v2 -> v3 * rebased on master * fix comment for gfn_to_memslot_approx * cmma_bitmap renamed to kvm_shadow_dirty_bitmap and easier to read * kvm->arch.migration_mode is not atomic any longer * renamed some local variables for more consistency v1 -> v2 * renamed _cmma_bitmap to cmma_bitmap and moved it to kvm-s390.h * renamed and/or removed some variables to improve readability * added some comments inline * simplified the code flow to improve readability Claudio Imbrenda (2): KVM: s390: a utility function for migration KVM: s390: Fix storage attributes migration with memory slots arch/s390/include/asm/kvm_host.h | 9 +- arch/s390/kvm/kvm-s390.c | 293 +++++++++++++++++++++++---------------- arch/s390/kvm/priv.c | 28 ++-- include/linux/kvm_host.h | 7 + virt/kvm/kvm_main.c | 2 +- 5 files changed, 203 insertions(+), 136 deletions(-) -- 2.7.4
