Re: [Qemu-devel] [RESEND PATCH v3 1/2] Minimal RAM API support

[Blue Swirl <blauwirbel@gmail.com>]

On Mon, Dec 13, 2010 at 8:47 PM, Alex Williamson
<alex.williamson@redhat.com> wrote:
> This adds a minimum chunk of Anthony's RAM API support so that we
> can identify actual VM RAM versus all the other things that make
> use of qemu_ram_alloc.
>
> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
> ---
>
>  Makefile.objs |    1 +
>  cpu-common.h  |    2 +
>  memory.c      |   97 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  memory.h      |   44 ++++++++++++++++++++++++++
>  4 files changed, 144 insertions(+), 0 deletions(-)
>  create mode 100644 memory.c
>  create mode 100644 memory.h
>
> diff --git a/Makefile.objs b/Makefile.objs
> index cebb945..47f3c3a 100644
> --- a/Makefile.objs
> +++ b/Makefile.objs
> @@ -172,6 +172,7 @@ hw-obj-y += pci.o pci_bridge.o msix.o msi.o
>  hw-obj-$(CONFIG_PCI) += pci_host.o pcie_host.o
>  hw-obj-$(CONFIG_PCI) += ioh3420.o xio3130_upstream.o xio3130_downstream.o
>  hw-obj-y += watchdog.o
> +hw-obj-y += memory.o
>  hw-obj-$(CONFIG_ISA_MMIO) += isa_mmio.o
>  hw-obj-$(CONFIG_ECC) += ecc.o
>  hw-obj-$(CONFIG_NAND) += nand.o
> diff --git a/cpu-common.h b/cpu-common.h
> index 6d4a898..f08f93b 100644
> --- a/cpu-common.h
> +++ b/cpu-common.h
> @@ -29,6 +29,8 @@ enum device_endian {
>  /* address in the RAM (different from a physical address) */
>  typedef unsigned long ram_addr_t;
>
> +#include "memory.h"
> +
>  /* memory API */
>
>  typedef void CPUWriteMemoryFunc(void *opaque, target_phys_addr_t addr, uint32_t value);
> diff --git a/memory.c b/memory.c
> new file mode 100644
> index 0000000..742776f
> --- /dev/null
> +++ b/memory.c
> @@ -0,0 +1,97 @@
> +/*
> + * RAM API
> + *
> + *  Copyright Red Hat, Inc. 2010
> + *
> + * Authors:
> + *  Alex Williamson <alex.williamson@redhat.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2.  See
> + * the COPYING file in the top-level directory.
> + *
> + */
> +#include "memory.h"
> +#include "range.h"
> +
> +typedef struct ram_slot {
> +    target_phys_addr_t start_addr;
> +    ram_addr_t size;
> +    ram_addr_t offset;
> +    QLIST_ENTRY(ram_slot) next;
> +} ram_slot;

Please see CODING_STYLE for structure naming.

> +
> +static QLIST_HEAD(ram_slots, ram_slot) ram_slots =
> +    QLIST_HEAD_INITIALIZER(ram_slots);
> +
> +static ram_slot *qemu_ram_find_slot(target_phys_addr_t start_addr,
> +                                   ram_addr_t size)
> +{
> +    ram_slot *slot;
> +
> +    QLIST_FOREACH(slot, &ram_slots, next) {
> +        if (slot->start_addr == start_addr && slot->size == size) {
> +            return slot;
> +        }
> +
> +        if (ranges_overlap(start_addr, size, slot->start_addr, slot->size)) {
> +            hw_error("Ram range overlaps existing slot\n");
> +        }
> +    }
> +
> +    return NULL;
> +}
> +
> +int qemu_ram_register(target_phys_addr_t start_addr, ram_addr_t size,
> +                      ram_addr_t phys_offset)
> +{
> +    ram_slot *slot;
> +
> +    if (!size) {
> +        return -EINVAL;
> +    }
> +
> +    assert(!qemu_ram_find_slot(start_addr, size));
> +
> +    slot = qemu_mallocz(sizeof(ram_slot));

Since you initialize every field by hand later, this could be qemu_malloc().

> +
> +    slot->start_addr = start_addr;
> +    slot->size = size;
> +    slot->offset = phys_offset;
> +
> +    QLIST_INSERT_HEAD(&ram_slots, slot, next);
> +
> +    cpu_register_physical_memory(slot->start_addr, slot->size, slot->offset);
> +
> +    return 0;
> +}
> +
> +void qemu_ram_unregister(target_phys_addr_t start_addr, ram_addr_t size)
> +{
> +    ram_slot *slot;
> +
> +    if (!size) {
> +        return;
> +    }
> +
> +    slot = qemu_ram_find_slot(start_addr, size);
> +    assert(slot != NULL);
> +
> +    QLIST_REMOVE(slot, next);
> +    qemu_free(slot);
> +    cpu_register_physical_memory(start_addr, size, IO_MEM_UNASSIGNED);
> +
> +    return;

Useless.