mbox series

[kvmtool,v1,00/17] Use memfd for guest vm memory allocation

Message ID 20221115111549.2784927-1-tabba@google.com (mailing list archive)
Headers show
Series Use memfd for guest vm memory allocation | expand

Message

Fuad Tabba Nov. 15, 2022, 11:15 a.m. UTC 
This patch series moves kvmtool from allocating guest vm memory
using anonymous mmap to using memfd/ftruncate. The main
motivation is to ease the transition to the fd-based kvm guest
memory proposal [*]. It also facilitates using ipc memory sharing
should that be needed in the future. Moreover, it removes the
need for using temporary files if the memory is backed by
hugetlbfs.

In the process of this rework, this patch series fixes a bug
(uninitalized return value). It also adds a memory allocation
function that allocates aligned memory without the need to
over-map/allocate. This facilitates refactoring, which simplifies
the code and removes a lot of the arch-specific code.

Cheers,
/fuad

[*] https://lore.kernel.org/all/20221025151344.3784230-1-chao.p.peng@linux.intel.com/

Fuad Tabba (17):
  Initialize the return value in kvm__for_each_mem_bank()
  Make mmap_hugetlbfs() static
  Rename parameter in mmap_anon_or_hugetlbfs()
  Add hostmem va to debug print
  Factor out getting the hugetlb block size
  Use memfd for hugetlbfs when allocating guest ram
  Make blk_size a parameter and pass it to mmap_hugetlbfs()
  Use memfd for all guest ram allocations
  Allocate pvtime memory with memfd
  Allocate vesa memory with memfd
  Add a function that allocates aligned memory if specified
  Use new function to align memory
  Remove struct fields and code used for alignment
  Replace kvm_arch_delete_ram with kvm_delete_ram
  Remove no-longer unused macro
  Factor out set_user_memory_region code
  Pass the memory file descriptor and offset when registering ram

 arm/aarch64/pvtime.c              |  20 ++++-
 arm/include/arm-common/kvm-arch.h |   7 --
 arm/kvm.c                         |  35 +++------
 framebuffer.c                     |   2 +
 hw/cfi_flash.c                    |   4 +-
 hw/vesa.c                         |  17 ++++-
 include/kvm/framebuffer.h         |   1 +
 include/kvm/kvm.h                 |  19 ++---
 include/kvm/util.h                |   7 +-
 kvm.c                             |  69 ++++++++++-------
 mips/kvm.c                        |  11 +--
 powerpc/kvm.c                     |   7 +-
 riscv/include/kvm/kvm-arch.h      |   7 --
 riscv/kvm.c                       |  26 ++-----
 util/util.c                       | 119 +++++++++++++++++++++++-------
 vfio/core.c                       |   3 +-
 x86/kvm.c                         |  11 +--
 17 files changed, 209 insertions(+), 156 deletions(-)


base-commit: e17d182ad3f797f01947fc234d95c96c050c534b