On Tue, Feb 27, 2024 at 11:37 PM Vikram Garhwal <vikram.garh...@amd.com>
wrote:
> From: Juergen Gross <jgr...@suse.com>
>
> qemu_map_ram_ptr() and qemu_ram_ptr_length() share quite some code, so
> modify qemu_ram_ptr_length() a little bit and use it for
> qemu_map_ram_ptr(), too.
>
> Signed-off-by: Juergen Gross <jgr...@suse.com>
> Signed-off-by: Vikram Garhwal <vikram.garh...@amd.com>
> Reviewed-by: Stefano Stabellini <sstabell...@kernel.org>
>
Reviewed-by: Edgar E. Iglesias <edgar.igles...@amd.com>
> ---
> system/physmem.c | 56 ++++++++++++++++++++----------------------------
> 1 file changed, 23 insertions(+), 33 deletions(-)
>
> diff --git a/system/physmem.c b/system/physmem.c
> index 84f3022099..949dcb20ba 100644
> --- a/system/physmem.c
> +++ b/system/physmem.c
> @@ -2163,43 +2163,17 @@ void qemu_ram_remap(ram_addr_t addr, ram_addr_t
> length)
> }
> #endif /* !_WIN32 */
>
> -/* Return a host pointer to ram allocated with qemu_ram_alloc.
> - * This should not be used for general purpose DMA. Use address_space_map
> - * or address_space_rw instead. For local memory (e.g. video ram) that the
> - * device owns, use memory_region_get_ram_ptr.
> - *
> - * Called within RCU critical section.
> - */
> -void *qemu_map_ram_ptr(RAMBlock *block, ram_addr_t addr)
> -{
> - if (block == NULL) {
> - block = qemu_get_ram_block(addr);
> - addr -= block->offset;
> - }
> -
> - if (xen_enabled() && block->host == NULL) {
> - /* We need to check if the requested address is in the RAM
> - * because we don't want to map the entire memory in QEMU.
> - * In that case just map until the end of the page.
> - */
> - if (block->offset == 0) {
> - return xen_map_cache(addr, 0, 0, false);
> - }
> -
> - block->host = xen_map_cache(block->offset, block->max_length, 1,
> false);
> - }
> - return ramblock_ptr(block, addr);
> -}
> -
> -/* Return a host pointer to guest's ram. Similar to qemu_map_ram_ptr
> - * but takes a size argument.
> +/*
> + * Return a host pointer to guest's ram.
> *
> * Called within RCU critical section.
> */
> static void *qemu_ram_ptr_length(RAMBlock *block, ram_addr_t addr,
> hwaddr *size, bool lock)
> {
> - if (*size == 0) {
> + hwaddr len = 0;
> +
> + if (size && *size == 0) {
> return NULL;
> }
>
> @@ -2207,7 +2181,10 @@ static void *qemu_ram_ptr_length(RAMBlock *block,
> ram_addr_t addr,
> block = qemu_get_ram_block(addr);
> addr -= block->offset;
> }
> - *size = MIN(*size, block->max_length - addr);
> + if (size) {
> + *size = MIN(*size, block->max_length - addr);
> + len = *size;
> + }
>
> if (xen_enabled() && block->host == NULL) {
> /* We need to check if the requested address is in the RAM
> @@ -2215,7 +2192,7 @@ static void *qemu_ram_ptr_length(RAMBlock *block,
> ram_addr_t addr,
> * In that case just map the requested area.
> */
> if (block->offset == 0) {
> - return xen_map_cache(addr, *size, lock, lock);
> + return xen_map_cache(addr, len, lock, lock);
> }
>
> block->host = xen_map_cache(block->offset, block->max_length, 1,
> lock);
> @@ -2224,6 +2201,19 @@ static void *qemu_ram_ptr_length(RAMBlock *block,
> ram_addr_t addr,
> return ramblock_ptr(block, addr);
> }
>
> +/*
> + * Return a host pointer to ram allocated with qemu_ram_alloc.
> + * This should not be used for general purpose DMA. Use address_space_map
> + * or address_space_rw instead. For local memory (e.g. video ram) that the
> + * device owns, use memory_region_get_ram_ptr.
> + *
> + * Called within RCU critical section.
> + */
> +void *qemu_map_ram_ptr(RAMBlock *ram_block, ram_addr_t addr)
> +{
> + return qemu_ram_ptr_length(ram_block, addr, NULL, false);
> +}
> +
> /* Return the offset of a hostpointer within a ramblock */
> ram_addr_t qemu_ram_block_host_offset(RAMBlock *rb, void *host)
> {
> --
> 2.17.1
>
>
>
