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687ca79789
These functions are not small, except for unlock_user without debugging enabled. Move them out of line, and add missing braces on the way. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Message-id: 20210212184902.1251044-18-richard.henderson@linaro.org [PMM: fixed the sense of an ifdef test in qemu.h] Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
111 lines
2.6 KiB
C
111 lines
2.6 KiB
C
/* User memory access */
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#include "qemu/osdep.h"
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#include "qemu/cutils.h"
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#include "qemu.h"
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void *lock_user(int type, abi_ulong guest_addr, long len, int copy)
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{
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if (!access_ok_untagged(type, guest_addr, len)) {
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return NULL;
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}
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#ifdef DEBUG_REMAP
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{
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void *addr;
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addr = g_malloc(len);
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if (copy) {
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memcpy(addr, g2h(guest_addr), len);
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} else {
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memset(addr, 0, len);
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}
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return addr;
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}
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#else
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return g2h_untagged(guest_addr);
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#endif
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}
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#ifdef DEBUG_REMAP
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void unlock_user(void *host_ptr, abi_ulong guest_addr, long len);
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{
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if (!host_ptr) {
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return;
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}
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if (host_ptr == g2h_untagged(guest_addr)) {
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return;
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}
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if (len > 0) {
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memcpy(g2h_untagged(guest_addr), host_ptr, len);
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}
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g_free(host_ptr);
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}
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#endif
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void *lock_user_string(abi_ulong guest_addr)
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{
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abi_long len = target_strlen(guest_addr);
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if (len < 0) {
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return NULL;
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}
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return lock_user(VERIFY_READ, guest_addr, (long)(len + 1), 1);
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}
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/* copy_from_user() and copy_to_user() are usually used to copy data
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* buffers between the target and host. These internally perform
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* locking/unlocking of the memory.
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*/
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abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len)
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{
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abi_long ret = 0;
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void *ghptr;
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if ((ghptr = lock_user(VERIFY_READ, gaddr, len, 1))) {
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memcpy(hptr, ghptr, len);
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unlock_user(ghptr, gaddr, 0);
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} else
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ret = -TARGET_EFAULT;
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return ret;
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}
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abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len)
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{
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abi_long ret = 0;
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void *ghptr;
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if ((ghptr = lock_user(VERIFY_WRITE, gaddr, len, 0))) {
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memcpy(ghptr, hptr, len);
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unlock_user(ghptr, gaddr, len);
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} else
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ret = -TARGET_EFAULT;
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return ret;
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}
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/* Return the length of a string in target memory or -TARGET_EFAULT if
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access error */
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abi_long target_strlen(abi_ulong guest_addr1)
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{
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uint8_t *ptr;
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abi_ulong guest_addr;
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int max_len, len;
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guest_addr = guest_addr1;
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for(;;) {
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max_len = TARGET_PAGE_SIZE - (guest_addr & ~TARGET_PAGE_MASK);
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ptr = lock_user(VERIFY_READ, guest_addr, max_len, 1);
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if (!ptr)
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return -TARGET_EFAULT;
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len = qemu_strnlen((const char *)ptr, max_len);
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unlock_user(ptr, guest_addr, 0);
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guest_addr += len;
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/* we don't allow wrapping or integer overflow */
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if (guest_addr == 0 ||
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(guest_addr - guest_addr1) > 0x7fffffff)
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return -TARGET_EFAULT;
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if (len != max_len)
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break;
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}
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return guest_addr - guest_addr1;
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}
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