diff options
| -rw-r--r-- | include/qemu/mmap-alloc.h | 2 | ||||
| -rw-r--r-- | util/mmap-alloc.c | 39 | ||||
| -rw-r--r-- | util/oslib-posix.c | 24 |
3 files changed, 42 insertions, 23 deletions
diff --git a/include/qemu/mmap-alloc.h b/include/qemu/mmap-alloc.h index 56388e689b..0899b2f01e 100644 --- a/include/qemu/mmap-alloc.h +++ b/include/qemu/mmap-alloc.h @@ -3,6 +3,8 @@ #include "qemu-common.h" +size_t qemu_fd_getpagesize(int fd); + void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared); void qemu_ram_munmap(void *ptr, size_t size); diff --git a/util/mmap-alloc.c b/util/mmap-alloc.c index c37acbe58e..54793a5dcf 100644 --- a/util/mmap-alloc.c +++ b/util/mmap-alloc.c @@ -14,6 +14,32 @@ #include <sys/mman.h> #include <assert.h> +#define HUGETLBFS_MAGIC 0x958458f6 + +#ifdef CONFIG_LINUX +#include <sys/vfs.h> +#endif + +size_t qemu_fd_getpagesize(int fd) +{ +#ifdef CONFIG_LINUX + struct statfs fs; + int ret; + + if (fd != -1) { + do { + ret = fstatfs(fd, &fs); + } while (ret != 0 && errno == EINTR); + + if (ret == 0 && fs.f_type == HUGETLBFS_MAGIC) { + return fs.f_bsize; + } + } +#endif + + return getpagesize(); +} + void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared) { /* @@ -21,7 +47,20 @@ void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared) * space, even if size is already aligned. */ size_t total = size + align; +#if defined(__powerpc64__) && defined(__linux__) + /* On ppc64 mappings in the same segment (aka slice) must share the same + * page size. Since we will be re-allocating part of this segment + * from the supplied fd, we should make sure to use the same page size, + * unless we are using the system page size, in which case anonymous memory + * is OK. Use align as a hint for the page size. + * In this case, set MAP_NORESERVE to avoid allocating backing store memory. + */ + int anonfd = fd == -1 || qemu_fd_getpagesize(fd) == getpagesize() ? -1 : fd; + int flags = anonfd == -1 ? MAP_ANONYMOUS : MAP_NORESERVE; + void *ptr = mmap(0, total, PROT_NONE, flags | MAP_PRIVATE, anonfd, 0); +#else void *ptr = mmap(0, total, PROT_NONE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); +#endif size_t offset = QEMU_ALIGN_UP((uintptr_t)ptr, align) - (uintptr_t)ptr; void *ptr1; diff --git a/util/oslib-posix.c b/util/oslib-posix.c index 914cef5c2c..d25f6715c7 100644 --- a/util/oslib-posix.c +++ b/util/oslib-posix.c @@ -46,7 +46,6 @@ extern int daemon(int, int); #else # define QEMU_VMALLOC_ALIGN getpagesize() #endif -#define HUGETLBFS_MAGIC 0x958458f6 #include <termios.h> #include <unistd.h> @@ -65,7 +64,6 @@ extern int daemon(int, int); #ifdef CONFIG_LINUX #include <sys/syscall.h> -#include <sys/vfs.h> #endif #ifdef __FreeBSD__ @@ -340,26 +338,6 @@ static void sigbus_handler(int signal) siglongjmp(sigjump, 1); } -static size_t fd_getpagesize(int fd) -{ -#ifdef CONFIG_LINUX - struct statfs fs; - int ret; - - if (fd != -1) { - do { - ret = fstatfs(fd, &fs); - } while (ret != 0 && errno == EINTR); - - if (ret == 0 && fs.f_type == HUGETLBFS_MAGIC) { - return fs.f_bsize; - } - } -#endif - - return getpagesize(); -} - void os_mem_prealloc(int fd, char *area, size_t memory) { int ret; @@ -387,7 +365,7 @@ void os_mem_prealloc(int fd, char *area, size_t memory) exit(1); } else { int i; - size_t hpagesize = fd_getpagesize(fd); + size_t hpagesize = qemu_fd_getpagesize(fd); size_t numpages = DIV_ROUND_UP(memory, hpagesize); /* MAP_POPULATE silently ignores failures */ |