mirror of
https://gitlab.com/qemu-project/qemu
synced 2024-11-05 20:35:44 +00:00
3b249d2661
qemu.h is included in various non-linux-user files (which mostly want the TaskState struct and the functions for doing usermode access to guest addresses like lock_user(), unlock_user(), get_user*(), etc). Split out the parts that are only used in linux-user itself into a new user-internals.h. This leaves qemu.h with basically three things: * the definition of the TaskState struct * the user-access functions and macros * do_brk() all of which are needed by code outside linux-user that includes qemu.h. The addition of all the extra #include lines was done with sed -i '/include.*qemu\.h/a #include "user-internals.h"' $(git grep -l 'include.*qemu\.h' linux-user) (and then undoing the change to fpa11.h). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-Id: <20210908154405.15417-8-peter.maydell@linaro.org> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
114 lines
2.7 KiB
C
114 lines
2.7 KiB
C
/* User memory access */
|
|
#include "qemu/osdep.h"
|
|
#include "qemu/cutils.h"
|
|
|
|
#include "qemu.h"
|
|
#include "user-internals.h"
|
|
|
|
void *lock_user(int type, abi_ulong guest_addr, ssize_t len, bool copy)
|
|
{
|
|
void *host_addr;
|
|
|
|
guest_addr = cpu_untagged_addr(thread_cpu, guest_addr);
|
|
if (!access_ok_untagged(type, guest_addr, len)) {
|
|
return NULL;
|
|
}
|
|
host_addr = g2h_untagged(guest_addr);
|
|
#ifdef DEBUG_REMAP
|
|
if (copy) {
|
|
host_addr = g_memdup(host_addr, len);
|
|
} else {
|
|
host_addr = g_malloc0(len);
|
|
}
|
|
#endif
|
|
return host_addr;
|
|
}
|
|
|
|
#ifdef DEBUG_REMAP
|
|
void unlock_user(void *host_ptr, abi_ulong guest_addr, ssize_t len)
|
|
{
|
|
void *host_ptr_conv;
|
|
|
|
if (!host_ptr) {
|
|
return;
|
|
}
|
|
host_ptr_conv = g2h(thread_cpu, guest_addr);
|
|
if (host_ptr == host_ptr_conv) {
|
|
return;
|
|
}
|
|
if (len > 0) {
|
|
memcpy(host_ptr_conv, host_ptr, len);
|
|
}
|
|
g_free(host_ptr);
|
|
}
|
|
#endif
|
|
|
|
void *lock_user_string(abi_ulong guest_addr)
|
|
{
|
|
ssize_t len = target_strlen(guest_addr);
|
|
if (len < 0) {
|
|
return NULL;
|
|
}
|
|
return lock_user(VERIFY_READ, guest_addr, len + 1, 1);
|
|
}
|
|
|
|
/* 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.
|
|
*/
|
|
int copy_from_user(void *hptr, abi_ulong gaddr, ssize_t len)
|
|
{
|
|
int ret = 0;
|
|
void *ghptr = lock_user(VERIFY_READ, gaddr, len, 1);
|
|
|
|
if (ghptr) {
|
|
memcpy(hptr, ghptr, len);
|
|
unlock_user(ghptr, gaddr, 0);
|
|
} else {
|
|
ret = -TARGET_EFAULT;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
int copy_to_user(abi_ulong gaddr, void *hptr, ssize_t len)
|
|
{
|
|
int ret = 0;
|
|
void *ghptr = lock_user(VERIFY_WRITE, gaddr, len, 0);
|
|
|
|
if (ghptr) {
|
|
memcpy(ghptr, hptr, len);
|
|
unlock_user(ghptr, gaddr, len);
|
|
} else {
|
|
ret = -TARGET_EFAULT;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Return the length of a string in target memory or -TARGET_EFAULT if
|
|
access error */
|
|
ssize_t target_strlen(abi_ulong guest_addr1)
|
|
{
|
|
uint8_t *ptr;
|
|
abi_ulong guest_addr;
|
|
size_t max_len, len;
|
|
|
|
guest_addr = guest_addr1;
|
|
for(;;) {
|
|
max_len = TARGET_PAGE_SIZE - (guest_addr & ~TARGET_PAGE_MASK);
|
|
ptr = lock_user(VERIFY_READ, guest_addr, max_len, 1);
|
|
if (!ptr)
|
|
return -TARGET_EFAULT;
|
|
len = qemu_strnlen((const char *)ptr, max_len);
|
|
unlock_user(ptr, guest_addr, 0);
|
|
guest_addr += len;
|
|
/* we don't allow wrapping or integer overflow */
|
|
if (guest_addr == 0 || (guest_addr - guest_addr1) > 0x7fffffff) {
|
|
return -TARGET_EFAULT;
|
|
}
|
|
if (len != max_len) {
|
|
break;
|
|
}
|
|
}
|
|
return guest_addr - guest_addr1;
|
|
}
|