Re: [Qemu-devel] [RFC][PATCH 04/16 v6] target-i386: implement cpu_get_memory_mapping()

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2012-02-09 04:21, Wen Congyang wrote:
> Walk cpu's page table and collect all virtual address and physical address mapping.
> Then, add these mapping into memory mapping list.
> 
> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
> ---
>  Makefile.target         |    2 +-
>  cpu-all.h               |    7 ++
>  target-i386/arch-dump.c |  254 +++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 262 insertions(+), 1 deletions(-)
>  create mode 100644 target-i386/arch-dump.c
> 
> diff --git a/Makefile.target b/Makefile.target
> index e35e464..d6e5684 100644
> --- a/Makefile.target
> +++ b/Makefile.target
> @@ -75,7 +75,7 @@ libobj-$(CONFIG_TCG_INTERPRETER) += tci.o
>  libobj-y += fpu/softfloat.o
>  libobj-y += op_helper.o helper.o
>  ifeq ($(TARGET_BASE_ARCH), i386)
> -libobj-y += cpuid.o
> +libobj-y += cpuid.o arch-dump.o
>  endif
>  libobj-$(TARGET_SPARC64) += vis_helper.o
>  libobj-$(CONFIG_NEED_MMU) += mmu.o
> diff --git a/cpu-all.h b/cpu-all.h
> index e2c3c49..4cd7fbb 100644
> --- a/cpu-all.h
> +++ b/cpu-all.h
> @@ -22,6 +22,7 @@
>  #include "qemu-common.h"
>  #include "qemu-tls.h"
>  #include "cpu-common.h"
> +#include "memory_mapping.h"
>  
>  /* some important defines:
>   *
> @@ -523,4 +524,10 @@ void dump_exec_info(FILE *f, fprintf_function cpu_fprintf);
>  int cpu_memory_rw_debug(CPUState *env, target_ulong addr,
>                          uint8_t *buf, int len, int is_write);
>  
> +#if defined(TARGET_I386)

Instead of collecting archs here, you could introduce some
HAVE_GET_MEMORY_MAPPING and let the targets that support that define it.

> +void cpu_get_memory_mapping(MemoryMappingList *list, CPUState *env);
> +#else
> +#define cpu_get_memory_mapping(list, env)

Better return an error from cpu_get_memory_mapping (and use static
inline) so that the caller can find out and report that dumping is not
supported for the current target.

> +#endif
> +
>  #endif /* CPU_ALL_H */
> diff --git a/target-i386/arch-dump.c b/target-i386/arch-dump.c
> new file mode 100644
> index 0000000..2e921c7
> --- /dev/null
> +++ b/target-i386/arch-dump.c
> @@ -0,0 +1,254 @@
> +/*
> + * i386 dump
> + *
> + * Copyright Fujitsu, Corp. 2011
> + *
> + * Authors:
> + *     Wen Congyang <wency@cn.fujitsu.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2.  See
> + * the COPYING file in the top-level directory.
> + *
> + */
> +
> +#include "cpu.h"
> +#include "cpu-all.h"
> +
> +/* PAE Paging or IA-32e Paging */
> +static void walk_pte(MemoryMappingList *list, target_phys_addr_t pte_start_addr,
> +                     int32_t a20_mask, target_ulong start_line_addr)
> +{
> +    target_phys_addr_t pte_addr, start_paddr;
> +    uint64_t pte;
> +    target_ulong start_vaddr;
> +    int i;
> +
> +    for (i = 0; i < 512; i++) {
> +        pte_addr = (pte_start_addr + i * 8) & a20_mask;
> +        pte = ldq_phys(pte_addr);
> +        if (!(pte & PG_PRESENT_MASK)) {
> +            /* not present */
> +            continue;
> +        }
> +
> +        start_paddr = (pte & ~0xfff) & ~(0x1ULL << 63);
> +        if (is_io_addr(start_paddr)) {
> +            /* I/O region */
> +            continue;
> +        }
> +
> +        start_vaddr = start_line_addr | ((i & 0x1fff) << 12);
> +        add_to_memory_mapping(list, start_paddr, start_vaddr, 1 << 12);
> +    }
> +}
> +
> +/* 32-bit Paging */
> +static void walk_pte2(MemoryMappingList *list,
> +                      target_phys_addr_t pte_start_addr, int32_t a20_mask,
> +                      target_ulong start_line_addr)
> +{
> +    target_phys_addr_t pte_addr, start_paddr;
> +    uint32_t pte;
> +    target_ulong start_vaddr;
> +    int i;
> +
> +    for (i = 0; i < 1024; i++) {
> +        pte_addr = (pte_start_addr + i * 4) & a20_mask;
> +        pte = ldl_phys(pte_addr);
> +        if (!(pte & PG_PRESENT_MASK)) {
> +            /* not present */
> +            continue;
> +        }
> +
> +        start_paddr = pte & ~0xfff;
> +        if (is_io_addr(start_paddr)) {
> +            /* I/O region */
> +            continue;
> +        }
> +
> +        start_vaddr = start_line_addr | ((i & 0x3ff) << 12);
> +        add_to_memory_mapping(list, start_paddr, start_vaddr, 1 << 12);
> +    }
> +}
> +
> +/* PAE Paging or IA-32e Paging */
> +static void walk_pde(MemoryMappingList *list, target_phys_addr_t pde_start_addr,
> +                     int32_t a20_mask, target_ulong start_line_addr)
> +{
> +    target_phys_addr_t pde_addr, pte_start_addr, start_paddr;
> +    uint64_t pde;
> +    target_ulong line_addr, start_vaddr;
> +    int i;
> +
> +    for (i = 0; i < 512; i++) {
> +        pde_addr = (pde_start_addr + i * 8) & a20_mask;
> +        pde = ldq_phys(pde_addr);
> +        if (!(pde & PG_PRESENT_MASK)) {
> +            /* not present */
> +            continue;
> +        }
> +
> +        line_addr = start_line_addr | ((i & 0x1ff) << 21);
> +        if (pde & PG_PSE_MASK) {
> +            /* 2 MB page */
> +            start_paddr = (pde & ~0x1fffff) & ~(0x1ULL << 63);
> +            if (is_io_addr(start_paddr)) {
> +                /* I/O region */
> +                continue;
> +            }
> +            start_vaddr = line_addr;
> +            add_to_memory_mapping(list, start_paddr, start_vaddr, 1 << 21);
> +            continue;
> +        }
> +
> +        pte_start_addr = (pde & ~0xfff) & a20_mask;
> +        walk_pte(list, pte_start_addr, a20_mask, line_addr);
> +    }
> +}
> +
> +/* 32-bit Paging */
> +static void walk_pde2(MemoryMappingList *list,
> +                      target_phys_addr_t pde_start_addr, int32_t a20_mask,
> +                      bool pse)
> +{
> +    target_phys_addr_t pde_addr, pte_start_addr, start_paddr;
> +    uint32_t pde;
> +    target_ulong line_addr, start_vaddr;
> +    int i;
> +
> +    for (i = 0; i < 1024; i++) {
> +        pde_addr = (pde_start_addr + i * 4) & a20_mask;
> +        pde = ldl_phys(pde_addr);
> +        if (!(pde & PG_PRESENT_MASK)) {
> +            /* not present */
> +            continue;
> +        }
> +
> +        line_addr = (((unsigned int)i & 0x3ff) << 22);
> +        if ((pde & PG_PSE_MASK) && pse) {
> +            /* 4 MB page */
> +            start_paddr = (pde & ~0x3fffff) | ((pde & 0x1fe000) << 19);
> +            if (is_io_addr(start_paddr)) {
> +                /* I/O region */
> +                continue;
> +            }
> +            start_vaddr = line_addr;
> +            add_to_memory_mapping(list, start_paddr, start_vaddr, 1 << 22);
> +            continue;
> +        }
> +
> +        pte_start_addr = (pde & ~0xfff) & a20_mask;
> +        walk_pte2(list, pte_start_addr, a20_mask, line_addr);
> +    }
> +}
> +
> +/* PAE Paging */
> +static void walk_pdpe2(MemoryMappingList *list,
> +                       target_phys_addr_t pdpe_start_addr, int32_t a20_mask)
> +{
> +    target_phys_addr_t pdpe_addr, pde_start_addr;
> +    uint64_t pdpe;
> +    target_ulong line_addr;
> +    int i;
> +
> +    for (i = 0; i < 4; i++) {
> +        pdpe_addr = (pdpe_start_addr + i * 8) & a20_mask;
> +        pdpe = ldq_phys(pdpe_addr);
> +        if (!(pdpe & PG_PRESENT_MASK)) {
> +            /* not present */
> +            continue;
> +        }
> +
> +        line_addr = (((unsigned int)i & 0x3) << 30);
> +        pde_start_addr = (pdpe & ~0xfff) & a20_mask;
> +        walk_pde(list, pde_start_addr, a20_mask, line_addr);
> +    }
> +}
> +
> +#ifdef TARGET_X86_64
> +/* IA-32e Paging */
> +static void walk_pdpe(MemoryMappingList *list,
> +                      target_phys_addr_t pdpe_start_addr, int32_t a20_mask,
> +                      target_ulong start_line_addr)
> +{
> +    target_phys_addr_t pdpe_addr, pde_start_addr, start_paddr;
> +    uint64_t pdpe;
> +    target_ulong line_addr, start_vaddr;
> +    int i;
> +
> +    for (i = 0; i < 512; i++) {
> +        pdpe_addr = (pdpe_start_addr + i * 8) & a20_mask;
> +        pdpe = ldq_phys(pdpe_addr);
> +        if (!(pdpe & PG_PRESENT_MASK)) {
> +            /* not present */
> +            continue;
> +        }
> +
> +        line_addr = start_line_addr | ((i & 0x1ffULL) << 30);
> +        if (pdpe & PG_PSE_MASK) {
> +            /* 1 GB page */
> +            start_paddr = (pdpe & ~0x3fffffff) & ~(0x1ULL << 63);
> +            if (is_io_addr(start_paddr)) {
> +                /* I/O region */
> +                continue;
> +            }
> +            start_vaddr = line_addr;
> +            add_to_memory_mapping(list, start_paddr, start_vaddr, 1 << 30);
> +            continue;
> +        }
> +
> +        pde_start_addr = (pdpe & ~0xfff) & a20_mask;
> +        walk_pde(list, pde_start_addr, a20_mask, line_addr);
> +    }
> +}
> +
> +/* IA-32e Paging */
> +static void walk_pml4e(MemoryMappingList *list,
> +                       target_phys_addr_t pml4e_start_addr, int32_t a20_mask)
> +{
> +    target_phys_addr_t pml4e_addr, pdpe_start_addr;
> +    uint64_t pml4e;
> +    target_ulong line_addr;
> +    int i;
> +
> +    for (i = 0; i < 512; i++) {
> +        pml4e_addr = (pml4e_start_addr + i * 8) & a20_mask;
> +        pml4e = ldq_phys(pml4e_addr);
> +        if (!(pml4e & PG_PRESENT_MASK)) {
> +            /* not present */
> +            continue;
> +        }
> +
> +        line_addr = ((i & 0x1ffULL) << 39) | (0xffffULL << 48);
> +        pdpe_start_addr = (pml4e & ~0xfff) & a20_mask;
> +        walk_pdpe(list, pdpe_start_addr, a20_mask, line_addr);
> +    }
> +}
> +#endif
> +
> +void cpu_get_memory_mapping(MemoryMappingList *list, CPUState *env)
> +{
> +    if (env->cr[4] & CR4_PAE_MASK) {
> +#ifdef TARGET_X86_64
> +        if (env->hflags & HF_LMA_MASK) {
> +            target_phys_addr_t pml4e_addr;
> +
> +            pml4e_addr = (env->cr[3] & ~0xfff) & env->a20_mask;
> +            walk_pml4e(list, pml4e_addr, env->a20_mask);
> +        } else
> +#endif
> +        {
> +            target_phys_addr_t pdpe_addr;
> +
> +            pdpe_addr = (env->cr[3] & ~0x1f) & env->a20_mask;
> +            walk_pdpe2(list, pdpe_addr, env->a20_mask);
> +        }
> +    } else {
> +        target_phys_addr_t pde_addr;
> +        bool pse;
> +
> +        pde_addr = (env->cr[3] & ~0xfff) & env->a20_mask;
> +        pse = !!(env->cr[4] & CR4_PSE_MASK);
> +        walk_pde2(list, pde_addr, env->a20_mask, pse);
> +    }
> +}

I haven't checked all paging details, but it looks good otherwise.

Jan

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