From 579a97f7ff4c0f958a5d8adcba717a205bb58567 Mon Sep 17 00:00:00 2001 From: bellard Date: Sun, 11 Nov 2007 14:26:47 +0000 Subject: Linux user memory access API change (initial patch by Thayne Harbaugh) git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3583 c046a42c-6fe2-441c-8c8c-71466251a162 --- linux-user/uaccess.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 linux-user/uaccess.c (limited to 'linux-user/uaccess.c') diff --git a/linux-user/uaccess.c b/linux-user/uaccess.c new file mode 100644 index 0000000..3f83818 --- /dev/null +++ b/linux-user/uaccess.c @@ -0,0 +1,51 @@ +/* User memory access */ +#include +#include + +#include "qemu.h" + +/* copy_from_user() and copy_to_user() are usually used to copy data + * buffers between the target and host. These internally perform + * locking/unlocking of the memory. + */ +abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len) +{ + abi_long ret = 0; + void *ghptr; + + if ((ghptr = lock_user(VERIFY_READ, gaddr, len, 1))) { + memcpy(hptr, ghptr, len); + unlock_user(ghptr, gaddr, 0); + } else + ret = -TARGET_EFAULT; + + return ret; +} + + +abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len) +{ + abi_long ret = 0; + void *ghptr; + + if ((ghptr = lock_user(VERIFY_WRITE, gaddr, len, 0))) { + memcpy(ghptr, hptr, len); + unlock_user(ghptr, gaddr, len); + } else + ret = -TARGET_EFAULT; + + return ret; +} + + +/* Return the length of a string in target memory. */ +/* FIXME - this doesn't check access_ok() - it's rather complicated to + * do it correctly because we need to check the bytes in a page and then + * skip to the next page and check the bytes there until we find the + * terminator. There should be a general function to do this that + * can look for any byte terminator in a buffer - not strlen(). + */ +abi_long target_strlen(abi_ulong gaddr) +{ + return strlen(g2h(gaddr)); +} -- cgit v1.1