dump: rebase from host-private RAMBlock offsets to guest-physical addresses

RAMBlock.offset                   --> GuestPhysBlock.target_start
RAMBlock.offset + RAMBlock.length --> GuestPhysBlock.target_end
RAMBlock.length                   --> GuestPhysBlock.target_end -
                                      GuestPhysBlock.target_start

"GuestPhysBlock.host_addr" is only used when writing the dump contents.

This patch enables "crash" to work with the vmcore by rebasing the vmcore
from the left side of the following diagram to the right side:

host-private
offset
relative
to ram_addr   RAMBlock                  guest-visible paddrs
            0 +-------------------+.....+-------------------+ 0
              |         ^         |     |        ^          |
              |       640 KB      |     |      640 KB       |
              |         v         |     |        v          |
  0x0000a0000 +-------------------+.....+-------------------+ 0x0000a0000
              |         ^         |     |XXXXXXXXXXXXXXXXXXX|
              |       384 KB      |     |XXXXXXXXXXXXXXXXXXX|
              |         v         |     |XXXXXXXXXXXXXXXXXXX|
  0x000100000 +-------------------+.....+-------------------+ 0x000100000
              |         ^         |     |        ^          |
              |       3583 MB     |     |      3583 MB      |
              |         v         |     |        v          |
  0x0e0000000 +-------------------+.....+-------------------+ 0x0e0000000
              |         ^         |.    |XXXXXXXXXXXXXXXXXXX|
              | above_4g_mem_size | .   |XXXX PCI hole XXXXX|
              |         v         |  .  |XXXX          XXXXX|
     ram_size +-------------------+   . |XXXX  512 MB  XXXXX|
                                   .   .|XXXXXXXXXXXXXXXXXXX|
                                    .   +-------------------+ 0x100000000
                                     .  |         ^         |
                                      . | above_4g_mem_size |
                                       .|         v         |
                                        +-------------------+ ram_size
                                                              + 512 MB

Related RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=981582

Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

diff --git a/dump.c b/dump.c
index 3fa33fccf062bdb3339f0f8eaa033a02349fb966..c0dae2c3ff934f372e6e2b773465d8a1148d1a99 100644 (file)
--- a/dump.c
+++ b/dump.c
@@ -70,7 +70,7 @@ typedef struct DumpState {
     hwaddr memory_offset;
     int fd;
 
-    RAMBlock *block;
+    GuestPhysBlock *next_block;
     ram_addr_t start;
     bool has_filter;
     int64_t begin;
@@ -391,14 +391,14 @@ static int write_data(DumpState *s, void *buf, int length)
 }
 
 /* write the memroy to vmcore. 1 page per I/O. */
-static int write_memory(DumpState *s, RAMBlock *block, ram_addr_t start,
+static int write_memory(DumpState *s, GuestPhysBlock *block, ram_addr_t start,
                         int64_t size)
 {
     int64_t i;
     int ret;
 
     for (i = 0; i < size / TARGET_PAGE_SIZE; i++) {
-        ret = write_data(s, block->host + start + i * TARGET_PAGE_SIZE,
+        ret = write_data(s, block->host_addr + start + i * TARGET_PAGE_SIZE,
                          TARGET_PAGE_SIZE);
         if (ret < 0) {
             return ret;
@@ -406,7 +406,7 @@ static int write_memory(DumpState *s, RAMBlock *block, ram_addr_t start,
     }
 
     if ((size % TARGET_PAGE_SIZE) != 0) {
-        ret = write_data(s, block->host + start + i * TARGET_PAGE_SIZE,
+        ret = write_data(s, block->host_addr + start + i * TARGET_PAGE_SIZE,
                          size % TARGET_PAGE_SIZE);
         if (ret < 0) {
             return ret;
@@ -423,7 +423,7 @@ static void get_offset_range(hwaddr phys_addr,
                              hwaddr *p_offset,
                              hwaddr *p_filesz)
 {
-    RAMBlock *block;
+    GuestPhysBlock *block;
     hwaddr offset = s->memory_offset;
     int64_t size_in_block, start;
 
@@ -437,35 +437,34 @@ static void get_offset_range(hwaddr phys_addr,
         }
     }
 
-    QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+    QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) {
         if (s->has_filter) {
-            if (block->offset >= s->begin + s->length ||
-                block->offset + block->length <= s->begin) {
+            if (block->target_start >= s->begin + s->length ||
+                block->target_end <= s->begin) {
                 /* This block is out of the range */
                 continue;
             }
 
-            if (s->begin <= block->offset) {
-                start = block->offset;
+            if (s->begin <= block->target_start) {
+                start = block->target_start;
             } else {
                 start = s->begin;
             }
 
-            size_in_block = block->length - (start - block->offset);
-            if (s->begin + s->length < block->offset + block->length) {
-                size_in_block -= block->offset + block->length -
-                                 (s->begin + s->length);
+            size_in_block = block->target_end - start;
+            if (s->begin + s->length < block->target_end) {
+                size_in_block -= block->target_end - (s->begin + s->length);
             }
         } else {
-            start = block->offset;
-            size_in_block = block->length;
+            start = block->target_start;
+            size_in_block = block->target_end - block->target_start;
         }
 
         if (phys_addr >= start && phys_addr < start + size_in_block) {
             *p_offset = phys_addr - start + offset;
 
             /* The offset range mapped from the vmcore file must not spill over
-             * the RAMBlock, clamp it. The rest of the mapping will be
+             * the GuestPhysBlock, clamp it. The rest of the mapping will be
              * zero-filled in memory at load time; see
              * <http://refspecs.linuxbase.org/elf/gabi4+/ch5.pheader.html>.
              */
@@ -613,7 +612,7 @@ static int dump_completed(DumpState *s)
     return 0;
 }
 
-static int get_next_block(DumpState *s, RAMBlock *block)
+static int get_next_block(DumpState *s, GuestPhysBlock *block)
 {
     while (1) {
         block = QTAILQ_NEXT(block, next);
@@ -623,16 +622,16 @@ static int get_next_block(DumpState *s, RAMBlock *block)
         }
 
         s->start = 0;
-        s->block = block;
+        s->next_block = block;
         if (s->has_filter) {
-            if (block->offset >= s->begin + s->length ||
-                block->offset + block->length <= s->begin) {
+            if (block->target_start >= s->begin + s->length ||
+                block->target_end <= s->begin) {
                 /* This block is out of the range */
                 continue;
             }
 
-            if (s->begin > block->offset) {
-                s->start = s->begin - block->offset;
+            if (s->begin > block->target_start) {
+                s->start = s->begin - block->target_start;
             }
         }
 
@@ -643,18 +642,18 @@ static int get_next_block(DumpState *s, RAMBlock *block)
 /* write all memory to vmcore */
 static int dump_iterate(DumpState *s)
 {
-    RAMBlock *block;
+    GuestPhysBlock *block;
     int64_t size;
     int ret;
 
     while (1) {
-        block = s->block;
+        block = s->next_block;
 
-        size = block->length;
+        size = block->target_end - block->target_start;
         if (s->has_filter) {
             size -= s->start;
-            if (s->begin + s->length < block->offset + block->length) {
-                size -= block->offset + block->length - (s->begin + s->length);
+            if (s->begin + s->length < block->target_end) {
+                size -= block->target_end - (s->begin + s->length);
             }
         }
         ret = write_memory(s, block, s->start, size);
@@ -689,23 +688,23 @@ static int create_vmcore(DumpState *s)
 
 static ram_addr_t get_start_block(DumpState *s)
 {
-    RAMBlock *block;
+    GuestPhysBlock *block;
 
     if (!s->has_filter) {
-        s->block = QTAILQ_FIRST(&ram_list.blocks);
+        s->next_block = QTAILQ_FIRST(&s->guest_phys_blocks.head);
         return 0;
     }
 
-    QTAILQ_FOREACH(block, &ram_list.blocks, next) {
-        if (block->offset >= s->begin + s->length ||
-            block->offset + block->length <= s->begin) {
+    QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) {
+        if (block->target_start >= s->begin + s->length ||
+            block->target_end <= s->begin) {
             /* This block is out of the range */
             continue;
         }
 
-        s->block = block;
-        if (s->begin > block->offset) {
-            s->start = s->begin - block->offset;
+        s->next_block = block;
+        if (s->begin > block->target_start) {
+            s->start = s->begin - block->target_start;
         } else {
             s->start = 0;
         }
@@ -758,7 +757,7 @@ static int dump_init(DumpState *s, int fd, bool paging, bool has_filter,
      * If the target architecture is not supported, cpu_get_dump_info() will
      * return -1.
      */
-    ret = cpu_get_dump_info(&s->dump_info);
+    ret = cpu_get_dump_info(&s->dump_info, &s->guest_phys_blocks);
     if (ret < 0) {
         error_set(errp, QERR_UNSUPPORTED);
         goto cleanup;
@@ -774,13 +773,13 @@ 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, &err);
+        qemu_get_guest_memory_mapping(&s->list, &s->guest_phys_blocks, &err);
         if (err != NULL) {
             error_propagate(errp, err);
             goto cleanup;
         }
     } else {
-        qemu_get_guest_simple_memory_mapping(&s->list);
+        qemu_get_guest_simple_memory_mapping(&s->list, &s->guest_phys_blocks);
     }
 
     if (s->has_filter) {

diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h
index b8c770f8d9dab3771274800d87e963c1b98657bf..19fafb2cf9e7f0f4e1bdbe6f15f60ad1642df1cd 100644 (file)
--- a/include/sysemu/dump.h
+++ b/include/sysemu/dump.h
@@ -20,7 +20,9 @@ typedef struct ArchDumpInfo {
     int d_class;    /* ELFCLASS32 or ELFCLASS64 */
 } ArchDumpInfo;
 
-int cpu_get_dump_info(ArchDumpInfo *info);
+struct GuestPhysBlockList; /* memory_mapping.h */
+int cpu_get_dump_info(ArchDumpInfo *info,
+                      const struct GuestPhysBlockList *guest_phys_blocks);
 ssize_t cpu_get_note_size(int class, int machine, int nr_cpus);
 
 #endif

diff --git a/include/sysemu/memory_mapping.h b/include/sysemu/memory_mapping.h
index b2d7d850c1a295c0d8750ce33dcd87b39499f708..a75d59a55db25a76d8c46912f72f764cd73e6b6a 100644 (file)
--- a/include/sysemu/memory_mapping.h
+++ b/include/sysemu/memory_mapping.h
@@ -68,10 +68,13 @@ void guest_phys_blocks_free(GuestPhysBlockList *list);
 void guest_phys_blocks_init(GuestPhysBlockList *list);
 void guest_phys_blocks_append(GuestPhysBlockList *list);
 
-void qemu_get_guest_memory_mapping(MemoryMappingList *list, Error **errp);
+void qemu_get_guest_memory_mapping(MemoryMappingList *list,
+                                   const GuestPhysBlockList *guest_phys_blocks,
+                                   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,
+                                  const GuestPhysBlockList *guest_phys_blocks);
 
 void memory_mapping_filter(MemoryMappingList *list, int64_t begin,
                            int64_t length);

diff --git a/memory_mapping.c b/memory_mapping.c
index 876f5aa7f5e7558ee4f3708bc732e5276c2eca56..eeeeb440266b6aa76fb2d3cc6bbf3bb7945fa34d 100644 (file)
--- a/memory_mapping.c
+++ b/memory_mapping.c
@@ -279,10 +279,12 @@ static CPUState *find_paging_enabled_cpu(CPUState *start_cpu)
     return NULL;
 }
 
-void qemu_get_guest_memory_mapping(MemoryMappingList *list, Error **errp)
+void qemu_get_guest_memory_mapping(MemoryMappingList *list,
+                                   const GuestPhysBlockList *guest_phys_blocks,
+                                   Error **errp)
 {
     CPUState *cpu, *first_paging_enabled_cpu;
-    RAMBlock *block;
+    GuestPhysBlock *block;
     ram_addr_t offset, length;
 
     first_paging_enabled_cpu = find_paging_enabled_cpu(first_cpu);
@@ -302,19 +304,21 @@ void qemu_get_guest_memory_mapping(MemoryMappingList *list, Error **errp)
      * If the guest doesn't use paging, the virtual address is equal to physical
      * address.
      */
-    QTAILQ_FOREACH(block, &ram_list.blocks, next) {
-        offset = block->offset;
-        length = block->length;
+    QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
+        offset = block->target_start;
+        length = block->target_end - block->target_start;
         create_new_memory_mapping(list, offset, offset, length);
     }
 }
 
-void qemu_get_guest_simple_memory_mapping(MemoryMappingList *list)
+void qemu_get_guest_simple_memory_mapping(MemoryMappingList *list,
+                                   const GuestPhysBlockList *guest_phys_blocks)
 {
-    RAMBlock *block;
+    GuestPhysBlock *block;
 
-    QTAILQ_FOREACH(block, &ram_list.blocks, next) {
-        create_new_memory_mapping(list, block->offset, 0, block->length);
+    QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
+        create_new_memory_mapping(list, block->target_start, 0,
+                                  block->target_end - block->target_start);
     }
 }
 

diff --git a/stubs/dump.c b/stubs/dump.c
index 43c9a3fa02dd24c6e94e4e136ce80ff6678636de..370cd96eb2fc650cb22c1faa9b04917ebfe565d6 100644 (file)
--- a/stubs/dump.c
+++ b/stubs/dump.c
@@ -16,7 +16,8 @@
 #include "qapi/qmp/qerror.h"
 #include "qmp-commands.h"
 
-int cpu_get_dump_info(ArchDumpInfo *info)
+int cpu_get_dump_info(ArchDumpInfo *info,
+                      const struct GuestPhysBlockList *guest_phys_blocks)
 {
     return -1;
 }

diff --git a/target-i386/arch_dump.c b/target-i386/arch_dump.c
index 10dc2284bf10c778d966f9673ac5d47f22320a3a..0bbed239f81da74ecace4daebd5cfdcc180c29c4 100644 (file)
--- a/target-i386/arch_dump.c
+++ b/target-i386/arch_dump.c
@@ -15,6 +15,7 @@
 #include "exec/cpu-all.h"
 #include "sysemu/dump.h"
 #include "elf.h"
+#include "sysemu/memory_mapping.h"
 
 #ifdef TARGET_X86_64
 typedef struct {
@@ -389,10 +390,11 @@ int x86_cpu_write_elf32_qemunote(WriteCoreDumpFunction f, CPUState *cs,
     return cpu_write_qemu_note(f, &cpu->env, opaque, 0);
 }
 
-int cpu_get_dump_info(ArchDumpInfo *info)
+int cpu_get_dump_info(ArchDumpInfo *info,
+                      const GuestPhysBlockList *guest_phys_blocks)
 {
     bool lma = false;
-    RAMBlock *block;
+    GuestPhysBlock *block;
 
 #ifdef TARGET_X86_64
     X86CPU *first_x86_cpu = X86_CPU(first_cpu);
@@ -412,8 +414,8 @@ int cpu_get_dump_info(ArchDumpInfo *info)
     } else {
         info->d_class = ELFCLASS32;
 
-        QTAILQ_FOREACH(block, &ram_list.blocks, next) {
-            if (block->offset + block->length > UINT_MAX) {
+        QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
+            if (block->target_end > UINT_MAX) {
                 /* The memory size is greater than 4G */
                 info->d_class = ELFCLASS64;
                 break;

diff --git a/target-s390x/arch_dump.c b/target-s390x/arch_dump.c
index f3e5144cc19b5fab9e78107e8c619f360b847679..9d36116242c1e0b5b87352cc62474b9536853b28 100644 (file)
--- a/target-s390x/arch_dump.c
+++ b/target-s390x/arch_dump.c
@@ -176,7 +176,8 @@ int s390_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
     return s390x_write_all_elf64_notes("CORE", f, cpu, cpuid, opaque);
 }
 
-int cpu_get_dump_info(ArchDumpInfo *info)
+int cpu_get_dump_info(ArchDumpInfo *info,
+                      const struct GuestPhysBlockList *guest_phys_blocks)
 {
     info->d_machine = EM_S390;
     info->d_endian = ELFDATA2MSB;