Re: [Qemu-devel] [PATCH 3/3] s390: Split dump-guest-memory memory mapping code

[Christian Borntraeger <borntraeger@de.ibm.com>]

CC Wen Congyang <wency@cn.fujitsu.com>


On 28/03/13 17:36, Jens Freimann wrote:
> From: Ekaterina Tumanova <tumanova_ek@ru.ibm.com>
> 
> Split dump-guest-memory memory mapping code and drop CONFIG_HAVE_GET_MEMORY_MAPPING
> for s390.

Jens, 
"drop CONFIG_HAVE_GET_MEMORY_MAPPING" seems like a leftover from our internal git which
had an earlier version that implemented a dummy memory mapping for s390.

So please re-do the patch description.

Wording-wise something like 
"Split out dump-guest-memory memory mapping code to allow dumping without memory mapping"
might be better

> 
> Part of the code from the memory_mapping.c was moved to separate
> memory_mapping_common.c file: memory-mapping functions, which dump code needs in
> both paths(CONFIG_HAVE_GET_MEMORY_MAPPING=y and CONFIG_HAVE_GET_MEMORY_MAPPING=n).
> These functions will be built the same time dump.o module is built (based on
> CONFIG_HAVE_CORE_DUMP statement).  Functions, which are left in memory_mapping.c
> are mapping ON specific, they will not be build if no
> CONFIG_HAVE_GET_MEMORY_MAPPING was specified for target architecture.
> In case when CONFIG_HAVE_GET_MEMORY_MAPPING is not specified, but paging is
> requested via command line ("-p" option), the memory_mapping-stub.c will issue
> an error.
> 
> Signed-Off-By: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
> Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
> ---
>  Makefile.target                 |   2 +-
>  dump.c                          |   8 +++-
>  include/sysemu/memory_mapping.h |  15 +++++-
>  memory_mapping-stub.c           |  14 +-----
>  memory_mapping.c                |  87 +--------------------------------
>  memory_mapping_common.c         | 103 ++++++++++++++++++++++++++++++++++++++++
>  6 files changed, 126 insertions(+), 103 deletions(-)
>  create mode 100644 memory_mapping_common.c
> 
> diff --git a/Makefile.target b/Makefile.target
> index 2bd6d14..f4eadc7 100644
> --- a/Makefile.target
> +++ b/Makefile.target
> @@ -116,7 +116,7 @@ obj-$(CONFIG_KVM) += kvm-all.o
>  obj-$(CONFIG_NO_KVM) += kvm-stub.o
>  obj-y += memory.o savevm.o cputlb.o
>  obj-$(CONFIG_HAVE_GET_MEMORY_MAPPING) += memory_mapping.o
> -obj-$(CONFIG_HAVE_CORE_DUMP) += dump.o
> +obj-$(CONFIG_HAVE_CORE_DUMP) += dump.o memory_mapping_common.o
>  obj-$(CONFIG_NO_GET_MEMORY_MAPPING) += memory_mapping-stub.o
>  obj-$(CONFIG_NO_CORE_DUMP) += dump-stub.o
>  LIBS+=-lz
> diff --git a/dump.c b/dump.c
> index fd1d0f6..574c292 100644
> --- a/dump.c
> +++ b/dump.c
> @@ -752,9 +752,13 @@ static int dump_init(DumpState *s, int fd, bool paging, bool has_filter,
>      /* get memory mapping */
>      memory_mapping_list_init(&s->list);
>      if (paging) {
> -        qemu_get_guest_memory_mapping(&s->list);
> +        qemu_get_guest_memory_mapping(&s->list, errp);
>      } else {
> -        qemu_get_guest_simple_memory_mapping(&s->list);
> +        qemu_get_guest_simple_memory_mapping(&s->list, errp);
> +    }
> +
> +    if (ret < 0) {
> +        goto cleanup;
>      }
> 
>      if (s->has_filter) {
> diff --git a/include/sysemu/memory_mapping.h b/include/sysemu/memory_mapping.h
> index 1256125..b7e7471 100644
> --- a/include/sysemu/memory_mapping.h
> +++ b/include/sysemu/memory_mapping.h
> @@ -15,6 +15,8 @@
>  #define MEMORY_MAPPING_H
> 
>  #include "qemu/queue.h"
> +#include "qapi/error.h"
> +#include "include/qapi/qmp/qerror.h"
> 
>  /* The physical and virtual address in the memory mapping are contiguous. */
>  typedef struct MemoryMapping {
> @@ -38,6 +40,15 @@ bool cpu_paging_enabled(CPUArchState *env);
>   * memory mapping's list. The region's virtual address starts with virt_addr,
>   * and is contiguous. The list is sorted by phys_addr.
>   */
> +
> +void memory_mapping_list_add_mapping_sorted(MemoryMappingList *list,
> +                                            MemoryMapping *mapping);
> +
> +void create_new_memory_mapping(MemoryMappingList *list,
> +                               hwaddr phys_addr,
> +                               hwaddr virt_addr,
> +                               ram_addr_t length);
> +
>  void memory_mapping_list_add_merge_sorted(MemoryMappingList *list,
>                                            hwaddr phys_addr,
>                                            hwaddr virt_addr,
> @@ -53,10 +64,10 @@ void memory_mapping_list_init(MemoryMappingList *list);
>   *   -1: failed
>   *   -2: unsupported
>   */
> -int qemu_get_guest_memory_mapping(MemoryMappingList *list);
> +int qemu_get_guest_memory_mapping(MemoryMappingList *list, Error **errp);
> 
>  /* get guest's memory mapping without do paging(virtual address is 0). */
> -void qemu_get_guest_simple_memory_mapping(MemoryMappingList *list);
> +void qemu_get_guest_simple_memory_mapping(MemoryMappingList *list, Error **errp);
> 
>  void memory_mapping_filter(MemoryMappingList *list, int64_t begin,
>                             int64_t length);
> diff --git a/memory_mapping-stub.c b/memory_mapping-stub.c
> index 24d5d67..fea489c 100644
> --- a/memory_mapping-stub.c
> +++ b/memory_mapping-stub.c
> @@ -15,19 +15,9 @@
>  #include "exec/cpu-all.h"
>  #include "sysemu/memory_mapping.h"
> 
> -int qemu_get_guest_memory_mapping(MemoryMappingList *list)
> +int qemu_get_guest_memory_mapping(MemoryMappingList *list, Error **errp)
>  {
> +    error_set(errp, QERR_UNSUPPORTED_COMMAND_OPTION, "paging", "dump-guest-memory", "current architecture");
>      return -2;
>  }
> 
> -int cpu_get_memory_mapping(MemoryMappingList *list,
> -					                                          CPUArchState *env)
> -{
> -    return -1;
> -}
> -
> -bool cpu_paging_enabled(CPUArchState *env)
> -{
> -    return true;
> -}
> -
> diff --git a/memory_mapping.c b/memory_mapping.c
> index ff45b3a..0d4c15b 100644
> --- a/memory_mapping.c
> +++ b/memory_mapping.c
> @@ -15,36 +15,6 @@
>  #include "exec/cpu-all.h"
>  #include "sysemu/memory_mapping.h"
> 
> -static void memory_mapping_list_add_mapping_sorted(MemoryMappingList *list,
> -                                                   MemoryMapping *mapping)
> -{
> -    MemoryMapping *p;
> -
> -    QTAILQ_FOREACH(p, &list->head, next) {
> -        if (p->phys_addr >= mapping->phys_addr) {
> -            QTAILQ_INSERT_BEFORE(p, mapping, next);
> -            return;
> -        }
> -    }
> -    QTAILQ_INSERT_TAIL(&list->head, mapping, next);
> -}
> -
> -static void create_new_memory_mapping(MemoryMappingList *list,
> -                                      hwaddr phys_addr,
> -                                      hwaddr virt_addr,
> -                                      ram_addr_t length)
> -{
> -    MemoryMapping *memory_mapping;
> -
> -    memory_mapping = g_malloc(sizeof(MemoryMapping));
> -    memory_mapping->phys_addr = phys_addr;
> -    memory_mapping->virt_addr = virt_addr;
> -    memory_mapping->length = length;
> -    list->last_mapping = memory_mapping;
> -    list->num++;
> -    memory_mapping_list_add_mapping_sorted(list, memory_mapping);
> -}
> -
>  static inline bool mapping_contiguous(MemoryMapping *map,
>                                        hwaddr phys_addr,
>                                        hwaddr virt_addr)
> @@ -145,26 +115,6 @@ void memory_mapping_list_add_merge_sorted(MemoryMappingList *list,
>      create_new_memory_mapping(list, phys_addr, virt_addr, length);
>  }
> 
> -void memory_mapping_list_free(MemoryMappingList *list)
> -{
> -    MemoryMapping *p, *q;
> -
> -    QTAILQ_FOREACH_SAFE(p, &list->head, next, q) {
> -        QTAILQ_REMOVE(&list->head, p, next);
> -        g_free(p);
> -    }
> -
> -    list->num = 0;
> -    list->last_mapping = NULL;
> -}
> -
> -void memory_mapping_list_init(MemoryMappingList *list)
> -{
> -    list->num = 0;
> -    list->last_mapping = NULL;
> -    QTAILQ_INIT(&list->head);
> -}
> -
>  static CPUArchState *find_paging_enabled_cpu(CPUArchState *start_cpu)
>  {
>      CPUArchState *env;
> @@ -178,7 +128,7 @@ static CPUArchState *find_paging_enabled_cpu(CPUArchState *start_cpu)
>      return NULL;
>  }
> 
> -int qemu_get_guest_memory_mapping(MemoryMappingList *list)
> +int qemu_get_guest_memory_mapping(MemoryMappingList *list, Error **errp)
>  {
>      CPUArchState *env, *first_paging_enabled_cpu;
>      RAMBlock *block;
> @@ -209,38 +159,3 @@ int qemu_get_guest_memory_mapping(MemoryMappingList *list)
>      return 0;
>  }
> 
> -void qemu_get_guest_simple_memory_mapping(MemoryMappingList *list)
> -{
> -    RAMBlock *block;
> -
> -    QTAILQ_FOREACH(block, &ram_list.blocks, next) {
> -        create_new_memory_mapping(list, block->offset, 0, block->length);
> -    }
> -}
> -
> -void memory_mapping_filter(MemoryMappingList *list, int64_t begin,
> -                           int64_t length)
> -{
> -    MemoryMapping *cur, *next;
> -
> -    QTAILQ_FOREACH_SAFE(cur, &list->head, next, next) {
> -        if (cur->phys_addr >= begin + length ||
> -            cur->phys_addr + cur->length <= begin) {
> -            QTAILQ_REMOVE(&list->head, cur, next);
> -            list->num--;
> -            continue;
> -        }
> -
> -        if (cur->phys_addr < begin) {
> -            cur->length -= begin - cur->phys_addr;
> -            if (cur->virt_addr) {
> -                cur->virt_addr += begin - cur->phys_addr;
> -            }
> -            cur->phys_addr = begin;
> -        }
> -
> -        if (cur->phys_addr + cur->length > begin + length) {
> -            cur->length -= cur->phys_addr + cur->length - begin - length;
> -        }
> -    }
> -}
> diff --git a/memory_mapping_common.c b/memory_mapping_common.c
> new file mode 100644
> index 0000000..faae044
> --- /dev/null
> +++ b/memory_mapping_common.c
> @@ -0,0 +1,103 @@
> +/*
> + * QEMU memory mapping
> + *
> + * Copyright Fujitsu, Corp. 2011, 2012
> + *
> + * Authors:
> + *     Wen Congyang <wency@cn.fujitsu.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + *
> + */
> +
> +#include "cpu.h"
> +#include "exec/cpu-all.h"
> +#include "sysemu/memory_mapping.h"
> +
> +void memory_mapping_list_add_mapping_sorted(MemoryMappingList *list,
> +                                            MemoryMapping *mapping)
> +{
> +    MemoryMapping *p;
> +
> +    QTAILQ_FOREACH(p, &list->head, next) {
> +        if (p->phys_addr >= mapping->phys_addr) {
> +            QTAILQ_INSERT_BEFORE(p, mapping, next);
> +            return;
> +        }
> +    }
> +    QTAILQ_INSERT_TAIL(&list->head, mapping, next);
> +}
> +
> +void create_new_memory_mapping(MemoryMappingList *list,
> +                               hwaddr phys_addr,
> +                               hwaddr virt_addr,
> +                               ram_addr_t length)
> +{
> +    MemoryMapping *memory_mapping;
> +
> +    memory_mapping = g_malloc(sizeof(MemoryMapping));
> +    memory_mapping->phys_addr = phys_addr;
> +    memory_mapping->virt_addr = virt_addr;
> +    memory_mapping->length = length;
> +    list->last_mapping = memory_mapping;
> +    list->num++;
> +    memory_mapping_list_add_mapping_sorted(list, memory_mapping);
> +}
> +
> +
> +void memory_mapping_list_free(MemoryMappingList *list)
> +{
> +    MemoryMapping *p, *q;
> +
> +    QTAILQ_FOREACH_SAFE(p, &list->head, next, q) {
> +        QTAILQ_REMOVE(&list->head, p, next);
> +        g_free(p);
> +    }
> +
> +    list->num = 0;
> +    list->last_mapping = NULL;
> +}
> +
> +void memory_mapping_list_init(MemoryMappingList *list)
> +{
> +    list->num = 0;
> +    list->last_mapping = NULL;
> +    QTAILQ_INIT(&list->head);
> +}
> +
> +void qemu_get_guest_simple_memory_mapping(MemoryMappingList *list, Error **errp)
> +{
> +    RAMBlock *block;
> +
> +    QTAILQ_FOREACH(block, &ram_list.blocks, next) {
> +        create_new_memory_mapping(list, block->offset, 0, block->length);
> +    }
> +}
> +
> +void memory_mapping_filter(MemoryMappingList *list, int64_t begin,
> +                           int64_t length)
> +{
> +    MemoryMapping *cur, *next;
> +
> +    QTAILQ_FOREACH_SAFE(cur, &list->head, next, next) {
> +        if (cur->phys_addr >= begin + length ||
> +            cur->phys_addr + cur->length <= begin) {
> +            QTAILQ_REMOVE(&list->head, cur, next);
> +            list->num--;
> +            continue;
> +        }
> +
> +        if (cur->phys_addr < begin) {
> +            cur->length -= begin - cur->phys_addr;
> +            if (cur->virt_addr) {
> +                cur->virt_addr += begin - cur->phys_addr;
> +            }
> +            cur->phys_addr = begin;
> +        }
> +
> +        if (cur->phys_addr + cur->length > begin + length) {
> +            cur->length -= cur->phys_addr + cur->length - begin - length;
> +        }
> +    }
> +}
>