Hi Elliot,
On Tue, May 09, 2023 at 01:47:47PM -0700, Elliot Berman wrote:
> When launching a virtual machine, Gunyah userspace allocates memory for
> the guest and informs Gunyah about these memory regions through
> SET_USER_MEMORY_REGION ioctl.
>
> Co-developed-by: Prakruthi Deepak Heragu <quic_pheragu@xxxxxxxxxxx>
> Signed-off-by: Prakruthi Deepak Heragu <quic_pheragu@xxxxxxxxxxx>
> Signed-off-by: Elliot Berman <quic_eberman@xxxxxxxxxxx>
> ---
> drivers/virt/gunyah/Makefile | 2 +-
> drivers/virt/gunyah/vm_mgr.c | 59 +++++++-
> drivers/virt/gunyah/vm_mgr.h | 26 ++++
> drivers/virt/gunyah/vm_mgr_mm.c | 236 ++++++++++++++++++++++++++++++++
> include/uapi/linux/gunyah.h | 37 +++++
> 5 files changed, 356 insertions(+), 4 deletions(-)
> create mode 100644 drivers/virt/gunyah/vm_mgr_mm.c
[...]
> +int gh_vm_mem_alloc(struct gh_vm *ghvm, struct gh_userspace_memory_region *region)
> +{
> + struct gh_vm_mem *mapping, *tmp_mapping;
> + struct page *curr_page, *prev_page;
> + struct gh_rm_mem_parcel *parcel;
> + int i, j, pinned, ret = 0;
> + unsigned int gup_flags;
> + size_t entry_size;
> + u16 vmid;
> +
> + if (!region->memory_size || !PAGE_ALIGNED(region->memory_size) ||
> + !PAGE_ALIGNED(region->userspace_addr) ||
> + !PAGE_ALIGNED(region->guest_phys_addr))
> + return -EINVAL;
> +
> + if (overflows_type(region->guest_phys_addr + region->memory_size, u64))
> + return -EOVERFLOW;
> +
> + ret = mutex_lock_interruptible(&ghvm->mm_lock);
> + if (ret)
> + return ret;
> +
> + mapping = __gh_vm_mem_find_by_label(ghvm, region->label);
> + if (mapping) {
> + ret = -EEXIST;
> + goto unlock;
> + }
> +
> + list_for_each_entry(tmp_mapping, &ghvm->memory_mappings, list) {
> + if (gh_vm_mem_overlap(tmp_mapping, region->guest_phys_addr,
> + region->memory_size)) {
> + ret = -EEXIST;
> + goto unlock;
> + }
> + }
> +
> + mapping = kzalloc(sizeof(*mapping), GFP_KERNEL_ACCOUNT);
> + if (!mapping) {
> + ret = -ENOMEM;
> + goto unlock;
> + }
> +
> + mapping->guest_phys_addr = region->guest_phys_addr;
> + mapping->npages = region->memory_size >> PAGE_SHIFT;
> + parcel = &mapping->parcel;
> + parcel->label = region->label;
> + parcel->mem_handle = GH_MEM_HANDLE_INVAL; /* to be filled later by mem_share/mem_lend */
> + parcel->mem_type = GH_RM_MEM_TYPE_NORMAL;
> +
> + ret = account_locked_vm(ghvm->mm, mapping->npages, true);
> + if (ret)
> + goto free_mapping;
> +
> + mapping->pages = kcalloc(mapping->npages, sizeof(*mapping->pages), GFP_KERNEL_ACCOUNT);
> + if (!mapping->pages) {
> + ret = -ENOMEM;
> + mapping->npages = 0; /* update npages for reclaim */
> + goto unlock_pages;
> + }
> +
> + gup_flags = FOLL_LONGTERM;
> + if (region->flags & GH_MEM_ALLOW_WRITE)
> + gup_flags |= FOLL_WRITE;
> +
> + pinned = pin_user_pages_fast(region->userspace_addr, mapping->npages,
> + gup_flags, mapping->pages);
> + if (pinned < 0) {
> + ret = pinned;
> + goto free_pages;
> + } else if (pinned != mapping->npages) {
> + ret = -EFAULT;
> + mapping->npages = pinned; /* update npages for reclaim */
> + goto unpin_pages;
> + }
Sorry if I missed it, but I still don't see where you reject file mappings
here.
This is also the wrong interface for upstream. Please get involved with
the fd-based guest memory discussions [1] and port your series to that.
This patch cannot be merged in its current form.
Will
[1] https://lore.kernel.org/kvm/20221202061347.1070246-1-chao.p.peng@xxxxxxxxxxxxxxx/
