Commit cd19cfa2 authored by Huang Ying's avatar Huang Ying Committed by Marcelo Tosatti
Browse files

Add qemu_ram_remap 



qemu_ram_remap() unmaps the specified RAM pages, then re-maps these
pages again.  This is used by KVM HWPoison support to clear HWPoisoned
page tables across guest rebooting, so that a new page may be
allocated later to recover the memory error.

[ Jan: style fixlets, WIN32 fix ]

Signed-off-by: default avatarHuang Ying <ying.huang@intel.com>
Signed-off-by: default avatarJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 75d49497

cpu-all.h

+4 −0
Original line number Diff line number Diff line
@@ -863,10 +863,14 @@ target_phys_addr_t cpu_get_phys_page_debug(CPUState *env, target_ulong addr); 
extern int phys_ram_fd;

extern ram_addr_t ram_size;



/* RAM is pre-allocated and passed into qemu_ram_alloc_from_ptr */

#define RAM_PREALLOC_MASK   (1 << 0)



typedef struct RAMBlock {

    uint8_t *host;

    ram_addr_t offset;

    ram_addr_t length;

    uint32_t flags;

    char idstr[256];

    QLIST_ENTRY(RAMBlock) next;

#if defined(__linux__) && !defined(TARGET_S390X)

cpu-common.h

+1 −0
Original line number Diff line number Diff line
@@ -50,6 +50,7 @@ ram_addr_t qemu_ram_alloc_from_ptr(DeviceState *dev, const char *name, 
                        ram_addr_t size, void *host);

ram_addr_t qemu_ram_alloc(DeviceState *dev, const char *name, ram_addr_t size);

void qemu_ram_free(ram_addr_t addr);

void qemu_ram_remap(ram_addr_t addr, ram_addr_t length);

/* This should only be used for ram local to a device.  */

void *qemu_get_ram_ptr(ram_addr_t addr);

/* Same but slower, to use for migration, where the order of

exec.c

+62 −1
Original line number Diff line number Diff line
@@ -2867,6 +2867,7 @@ ram_addr_t qemu_ram_alloc_from_ptr(DeviceState *dev, const char *name, 


    if (host) {

        new_block->host = host;

        new_block->flags |= RAM_PREALLOC_MASK;

    } else {

        if (mem_path) {

#if defined (__linux__) && !defined(TARGET_S390X)
@@ -2920,7 +2921,9 @@ void qemu_ram_free(ram_addr_t addr) 
    QLIST_FOREACH(block, &ram_list.blocks, next) {

        if (addr == block->offset) {

            QLIST_REMOVE(block, next);

            if (mem_path) {

            if (block->flags & RAM_PREALLOC_MASK) {

                ;

            } else if (mem_path) {

#if defined (__linux__) && !defined(TARGET_S390X)

                if (block->fd) {

                    munmap(block->host, block->length);
@@ -2943,6 +2946,64 @@ void qemu_ram_free(ram_addr_t addr) 


}



#ifndef _WIN32

void qemu_ram_remap(ram_addr_t addr, ram_addr_t length)

{

    RAMBlock *block;

    ram_addr_t offset;

    int flags;

    void *area, *vaddr;



    QLIST_FOREACH(block, &ram_list.blocks, next) {

        offset = addr - block->offset;

        if (offset < block->length) {

            vaddr = block->host + offset;

            if (block->flags & RAM_PREALLOC_MASK) {

                ;

            } else {

                flags = MAP_FIXED;

                munmap(vaddr, length);

                if (mem_path) {

#if defined(__linux__) && !defined(TARGET_S390X)

                    if (block->fd) {

#ifdef MAP_POPULATE

                        flags |= mem_prealloc ? MAP_POPULATE | MAP_SHARED :

                            MAP_PRIVATE;

#else

                        flags |= MAP_PRIVATE;

#endif

                        area = mmap(vaddr, length, PROT_READ | PROT_WRITE,

                                    flags, block->fd, offset);

                    } else {

                        flags |= MAP_PRIVATE | MAP_ANONYMOUS;

                        area = mmap(vaddr, length, PROT_READ | PROT_WRITE,

                                    flags, -1, 0);

                    }

#endif

                } else {

#if defined(TARGET_S390X) && defined(CONFIG_KVM)

                    flags |= MAP_SHARED | MAP_ANONYMOUS;

                    area = mmap(vaddr, length, PROT_EXEC|PROT_READ|PROT_WRITE,

                                flags, -1, 0);

#else

                    flags |= MAP_PRIVATE | MAP_ANONYMOUS;

                    area = mmap(vaddr, length, PROT_READ | PROT_WRITE,

                                flags, -1, 0);

#endif

                }

                if (area != vaddr) {

                    fprintf(stderr, "Could not remap addr: %lx@%lx\n",

                            length, addr);

                    exit(1);

                }

                qemu_madvise(vaddr, length, QEMU_MADV_MERGEABLE);

            }

            return;

        }

    }

}

#endif /* !_WIN32 */



/* Return a host pointer to ram allocated with qemu_ram_alloc.

   With the exception of the softmmu code in this file, this should

   only be used for local memory (e.g. video ram) that the device owns,