On Thu, Sep 19, 2024 at 02:46:25PM +0100, d...@treblig.org wrote:
> From: "Dr. David Alan Gilbert" <d...@treblig.org>
>
> Use the uffd_copy_page, uffd_zero_page and uffd_wakeup helpers
> rather than calling ioctl ourselves.
>
> They return -errno on error, and print an error_report themselves.
> I think this actually makes postcopy_place_page actually more
> consistent in it's callers.
>
> Signed-off-by: Dr. David Alan Gilbert <d...@treblig.org>
> ---
> migration/postcopy-ram.c | 47 +++++++++++-----------------------------
> 1 file changed, 13 insertions(+), 34 deletions(-)
>
> diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
> index 1c374b7ea1..e2b318d3da 100644
> --- a/migration/postcopy-ram.c
> +++ b/migration/postcopy-ram.c
> @@ -746,18 +746,9 @@ int postcopy_wake_shared(struct PostCopyFD *pcfd,
> RAMBlock *rb)
> {
> size_t pagesize = qemu_ram_pagesize(rb);
> - struct uffdio_range range;
> - int ret;
> trace_postcopy_wake_shared(client_addr, qemu_ram_get_idstr(rb));
> - range.start = ROUND_DOWN(client_addr, pagesize);
> - range.len = pagesize;
> - ret = ioctl(pcfd->fd, UFFDIO_WAKE, &range);
> - if (ret) {
> - error_report("%s: Failed to wake: %zx in %s (%s)",
> - __func__, (size_t)client_addr, qemu_ram_get_idstr(rb),
> - strerror(errno));
> - }
> - return ret;
> + return uffd_wakeup(pcfd->fd, (void *)ROUND_DOWN(client_addr, pagesize),
> + pagesize);
> }
There's a build issue on i386:
../migration/postcopy-ram.c: In function ‘postcopy_wake_shared’:
../migration/postcopy-ram.c:750:34: error: cast to pointer from integer of
different size [-Werror=int-to-pointer-cast]
750 | return uffd_wakeup(pcfd->fd, (void *)ROUND_DOWN(client_addr,
pagesize),
| ^
The plan is to squash below fix:
=========8<===========
diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index 03a63ef5cd..83f6160a36 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
-@@ -747,7 +747,8 @@ int postcopy_wake_shared(struct PostCopyFD *pcfd,
{
size_t pagesize = qemu_ram_pagesize(rb);
trace_postcopy_wake_shared(client_addr, qemu_ram_get_idstr(rb));
- return uffd_wakeup(pcfd->fd, (void *)ROUND_DOWN(client_addr, pagesize),
+ return uffd_wakeup(pcfd->fd,
+ (void *)(uintptr_t)ROUND_DOWN(client_addr, pagesize),
pagesize);
}
=========8<===========
Thanks,
--
Peter Xu
