From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33778) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aE5Jn-0001gc-Vn for qemu-devel@nongnu.org; Tue, 29 Dec 2015 20:12:48 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aE5Jk-0005Ri-Pg for qemu-devel@nongnu.org; Tue, 29 Dec 2015 20:12:47 -0500 Received: from mail113-251.mail.alibaba.com ([205.204.113.251]:51078 helo=us-alimail-mta2.hst.scl.en.alidc.net) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aE5Jk-0005Re-AN for qemu-devel@nongnu.org; Tue, 29 Dec 2015 20:12:44 -0500 From: chengang@emindsoft.com.cn Date: Wed, 30 Dec 2015 09:11:44 +0800 Message-Id: <1451437904-3752-1-git-send-email-chengang@emindsoft.com.cn> Subject: [Qemu-devel] [PATCH] linux-user/mmap.c: Support shared memory mapping in mmap_frag() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: riku.voipio@iki.fi, laurent@vivier.eu Cc: peter.maydell@linaro.org, Chen Gang , Chen Gang , qemu-devel@nongnu.org, rth@twiddle.net From: Chen Gang It is a temporary fix for i386 target system running Windows. Also remove useless variable 'p'. Signed-off-by: Chen Gang --- linux-user/mmap.c | 22 +++++++++++++++++++--- 1 files changed, 19 insertions(+), 3 deletions(-) diff --git a/linux-user/mmap.c b/linux-user/mmap.c index 445e8c6..07758d4 100644 --- a/linux-user/mmap.c +++ b/linux-user/mmap.c @@ -156,12 +156,28 @@ static int mmap_frag(abi_ulong real_start, prot1 |= page_get_flags(addr); } + /* + * It is a temporary fix. Normally, target system will let shared memory + * aligned with 64KB, and allocate them near with each other, no any other + * kinds of mapping regions nearby. e.g. Windows on i386. + */ + if ((start == real_start) && (flags & MAP_SHARED)) { + if (prot1) { + munmap(host_start, qemu_host_page_size); + } + if (mmap(host_start, qemu_host_page_size, prot, flags, fd, offset) + == MAP_FAILED) { + return -1; + } + return 0; + } + if (prot1 == 0) { /* no page was there, so we allocate one */ - void *p = mmap(host_start, qemu_host_page_size, prot, - flags | MAP_ANONYMOUS, -1, 0); - if (p == MAP_FAILED) + if (mmap(host_start, qemu_host_page_size, prot, flags | MAP_ANONYMOUS, + -1, 0) == MAP_FAILED) { return -1; + } prot1 = prot; } prot1 &= PAGE_BITS; -- 1.7.3.4