diff options
Diffstat (limited to 'linux-user')
| -rw-r--r-- | linux-user/mmap.c | 24 |
1 files changed, 3 insertions, 21 deletions
diff --git a/linux-user/mmap.c b/linux-user/mmap.c index c0946322fb..49cfa873e0 100644 --- a/linux-user/mmap.c +++ b/linux-user/mmap.c @@ -898,23 +898,6 @@ abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size, return new_addr; } -static bool can_passthrough_madvise(abi_ulong start, abi_ulong end) -{ - ulong addr; - - if ((start | end) & ~qemu_host_page_mask) { - return false; - } - - for (addr = start; addr < end; addr += TARGET_PAGE_SIZE) { - if (!(page_get_flags(addr) & PAGE_PASSTHROUGH)) { - return false; - } - } - - return true; -} - abi_long target_madvise(abi_ulong start, abi_ulong len_in, int advice) { abi_ulong len, end; @@ -964,9 +947,8 @@ abi_long target_madvise(abi_ulong start, abi_ulong len_in, int advice) * * A straight passthrough for those may not be safe because qemu sometimes * turns private file-backed mappings into anonymous mappings. - * can_passthrough_madvise() helps to check if a passthrough is possible by - * comparing mappings that are known to have the same semantics in the host - * and the guest. In this case passthrough is safe. + * If all guest pages have PAGE_PASSTHROUGH set, mappings have the + * same semantics for the host as for the guest. * * We pass through MADV_WIPEONFORK and MADV_KEEPONFORK if possible and * return failure if not. @@ -984,7 +966,7 @@ abi_long target_madvise(abi_ulong start, abi_ulong len_in, int advice) ret = -EINVAL; /* fall through */ case MADV_DONTNEED: - if (can_passthrough_madvise(start, end)) { + if (page_check_range(start, len, PAGE_PASSTHROUGH)) { ret = get_errno(madvise(g2h_untagged(start), len, advice)); if ((advice == MADV_DONTNEED) && (ret == 0)) { page_reset_target_data(start, start + len - 1); |