* Denis Plotnikov (dplotnikov@virtuozzo.com) wrote:
> Signed-off-by: Denis Plotnikov <dplotnikov@virtuozzo.com>
> ---
> migration/ram.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++
> migration/ram.h | 3 +++
> 2 files changed, 57 insertions(+)
>
> diff --git a/migration/ram.c b/migration/ram.c
> index 27d3403435..ce3dead932 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -1555,6 +1555,60 @@ void ram_block_list_destroy(void)
> }
> }
>
> +static int mem_protect(void *addr, uint64_t length, int prot)
> +{
> + int ret = mprotect(addr, length, prot);
> +
> + if (ret < 0) {
> + error_report("%s: Can't change protection on ram block at %p",
> + __func__, addr);
> + }
> +
> + return ret;
> +}
> +
> +static int ram_set_ro(void *addr, uint64_t length)
> +{
> + return mem_protect(addr, length, PROT_READ);
> +}
> +
> +static int ram_set_rw(void *addr, uint64_t length)
> +{
> + return mem_protect(addr, length, PROT_READ | PROT_WRITE);
> +}
> +
> +int ram_block_list_set_readonly(void)
> +{
> + RAMBlock *block = NULL;
> + RamBlockList *block_list = ram_bgs_block_list_get();
> + int ret = 0;
> +
> + QLIST_FOREACH(block, block_list, bgs_next) {
> + ret = ram_set_ro(block->host, block->used_length);
> + if (ret) {
> + break;
> + }
> + }
> +
> + return ret;
> +}
> +
> +int ram_block_list_set_writable(void)
> +{
> + RAMBlock *block = NULL;
> + RamBlockList *block_list = ram_bgs_block_list_get();
> + int ret = 0;
> +
> + QLIST_FOREACH(block, block_list, bgs_next) {
> + ret = ram_set_rw(block->host, block->used_length);
> + if (ret) {
> + break;
> + }
> + }
Do you need to keep track of who was writeable previously
to avoid changing blocks that should be read-only,
Or are all RAMBlocks currently mapped rw?
Dave
> + return ret;
> +}
> +
> static void ram_page_buffer_decrease_used(void)
> {
> qemu_event_reset(&ram_state->page_buffer.used_decreased);
> diff --git a/migration/ram.h b/migration/ram.h
> index 7c802c1d7f..4c463597a5 100644
> --- a/migration/ram.h
> +++ b/migration/ram.h
> @@ -71,4 +71,7 @@ RAMBlock *ram_bgs_block_find(uint8_t *address, ram_addr_t *page_offset);
> void *ram_page_buffer_get(void);
> int ram_page_buffer_free(void *buffer);
>
> +int ram_block_list_set_readonly(void);
> +int ram_block_list_set_writable(void);
> +
> #endif
> --
> 2.17.0
>
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK