Commit 04a8f72e authored by Igor Druzhinin's avatar Igor Druzhinin Committed by Stefano Stabellini
Browse files

xen/hvm: correct reporting of modified memory under physmap during migration 



When global_log_dirty is enabled VRAM modification tracking never
worked correctly. The address that is passed to xen_hvm_modified_memory()
is not the effective PFN but RAM block address which is not the same
for VRAM.

We need to make a translation for this address into PFN using
physmap. Since there is no way to access physmap properly inside
xen_hvm_modified_memory() let's make it a global structure.

Signed-off-by: default avatarIgor Druzhinin <igor.druzhinin@citrix.com>
Acked-by: default avatarAnthony PERARD <anthony.perard@citrix.com>
Signed-off-by: default avatarStefano Stabellini <sstabellini@kernel.org>
parent c181ddaa

hw/i386/xen/xen-hvm.c

+19 −18
Original line number Diff line number Diff line
@@ -86,6 +86,8 @@ typedef struct XenPhysmap { 
    QLIST_ENTRY(XenPhysmap) list;

} XenPhysmap;



static QLIST_HEAD(, XenPhysmap) xen_physmap;



typedef struct XenIOState {

    ioservid_t ioservid;

    shared_iopage_t *shared_page;
@@ -107,7 +109,6 @@ typedef struct XenIOState { 
    MemoryListener memory_listener;

    MemoryListener io_listener;

    DeviceListener device_listener;

    QLIST_HEAD(, XenPhysmap) physmap;

    hwaddr free_phys_offset;

    const XenPhysmap *log_for_dirtybit;
@@ -274,14 +275,13 @@ void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr, 
    g_free(pfn_list);

}



static XenPhysmap *get_physmapping(XenIOState *state,

                                   hwaddr start_addr, ram_addr_t size)

static XenPhysmap *get_physmapping(hwaddr start_addr, ram_addr_t size)

{

    XenPhysmap *physmap = NULL;



    start_addr &= TARGET_PAGE_MASK;



    QLIST_FOREACH(physmap, &state->physmap, list) {

    QLIST_FOREACH(physmap, &xen_physmap, list) {

        if (range_covers_byte(physmap->start_addr, physmap->size, start_addr)) {

            return physmap;

        }
@@ -289,23 +289,21 @@ static XenPhysmap *get_physmapping(XenIOState *state, 
    return NULL;

}



#ifdef XEN_COMPAT_PHYSMAP

static hwaddr xen_phys_offset_to_gaddr(hwaddr start_addr,

                                                   ram_addr_t size, void *opaque)

static hwaddr xen_phys_offset_to_gaddr(hwaddr phys_offset, ram_addr_t size)

{

    hwaddr addr = start_addr & TARGET_PAGE_MASK;

    XenIOState *xen_io_state = opaque;

    hwaddr addr = phys_offset & TARGET_PAGE_MASK;

    XenPhysmap *physmap = NULL;



    QLIST_FOREACH(physmap, &xen_io_state->physmap, list) {

    QLIST_FOREACH(physmap, &xen_physmap, list) {

        if (range_covers_byte(physmap->phys_offset, physmap->size, addr)) {

            return physmap->start_addr;

            return physmap->start_addr + (phys_offset - physmap->phys_offset);

        }

    }



    return start_addr;

    return phys_offset;

}



#ifdef XEN_COMPAT_PHYSMAP

static int xen_save_physmap(XenIOState *state, XenPhysmap *physmap)

{

    char path[80], value[17];
@@ -355,7 +353,7 @@ static int xen_add_to_physmap(XenIOState *state, 
    hwaddr phys_offset = memory_region_get_ram_addr(mr);

    const char *mr_name;



    if (get_physmapping(state, start_addr, size)) {

    if (get_physmapping(start_addr, size)) {

        return 0;

    }

    if (size <= 0) {
@@ -384,7 +382,7 @@ go_physmap: 
    physmap->name = mr_name;

    physmap->phys_offset = phys_offset;



    QLIST_INSERT_HEAD(&state->physmap, physmap, list);

    QLIST_INSERT_HEAD(&xen_physmap, physmap, list);



    if (runstate_check(RUN_STATE_INMIGRATE)) {

        /* Now when we have a physmap entry we can replace a dummy mapping with
@@ -428,7 +426,7 @@ static int xen_remove_from_physmap(XenIOState *state, 
    XenPhysmap *physmap = NULL;

    hwaddr phys_offset = 0;



    physmap = get_physmapping(state, start_addr, size);

    physmap = get_physmapping(start_addr, size);

    if (physmap == NULL) {

        return -1;

    }
@@ -597,7 +595,7 @@ static void xen_sync_dirty_bitmap(XenIOState *state, 
    int rc, i, j;

    const XenPhysmap *physmap = NULL;



    physmap = get_physmapping(state, start_addr, size);

    physmap = get_physmapping(start_addr, size);

    if (physmap == NULL) {

        /* not handled */

        return;
@@ -1222,7 +1220,7 @@ static void xen_read_physmap(XenIOState *state) 
                xen_domid, entries[i]);

        physmap->name = xs_read(state->xenstore, 0, path, &len);



        QLIST_INSERT_HEAD(&state->physmap, physmap, list);

        QLIST_INSERT_HEAD(&xen_physmap, physmap, list);

    }

    free(entries);

}
@@ -1374,7 +1372,6 @@ void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory) 
    qemu_add_vm_change_state_handler(xen_hvm_change_state_handler, state);



    state->memory_listener = xen_memory_listener;

    QLIST_INIT(&state->physmap);

    memory_listener_register(&state->memory_listener, &address_space_memory);

    state->log_for_dirtybit = NULL;
@@ -1390,6 +1387,8 @@ void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory) 
        goto err;

    }

    xen_be_register_common();



    QLIST_INIT(&xen_physmap);

    xen_read_physmap(state);



    /* Disable ACPI build because Xen handles it */
@@ -1461,6 +1460,8 @@ void xen_hvm_modified_memory(ram_addr_t start, ram_addr_t length) 
        int rc;

        ram_addr_t start_pfn, nb_pages;



        start = xen_phys_offset_to_gaddr(start, length);



        if (length == 0) {

            length = TARGET_PAGE_SIZE;

        }

hw/i386/xen/xen-mapcache.c

+1 −1
Original line number Diff line number Diff line
@@ -319,7 +319,7 @@ tryagain: 
        mapcache->last_entry = NULL;

#ifdef XEN_COMPAT_PHYSMAP

        if (!translated && mapcache->phys_offset_to_gaddr) {

            phys_addr = mapcache->phys_offset_to_gaddr(phys_addr, size, mapcache->opaque);

            phys_addr = mapcache->phys_offset_to_gaddr(phys_addr, size);

            translated = true;

            goto tryagain;

        }

include/sysemu/xen-mapcache.h

+2 −3
Original line number Diff line number Diff line
@@ -9,9 +9,8 @@ 
#ifndef XEN_MAPCACHE_H

#define XEN_MAPCACHE_H



typedef hwaddr (*phys_offset_to_gaddr_t)(hwaddr start_addr,

                                                     ram_addr_t size,

                                                     void *opaque);

typedef hwaddr (*phys_offset_to_gaddr_t)(hwaddr phys_offset,

                                         ram_addr_t size);

#ifdef CONFIG_XEN



void xen_map_cache_init(phys_offset_to_gaddr_t f,